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Perception of climate change-related forest dieback in mountain forests among the local population
(2023)
Mountain forests provide multiple benefits but are threatened by climate change-induced forest dieback. Although many studies summarize perceptions of forest ecosystem services, relatively few deal with mountain forests. The local population’s perception of forest dieback in mountain forests in relation to climate change has rarely been investigated so far. Their perspective is relevant as local people are often deeply attached to “their” forests, they actively use forest ecosystems and—as voters and taxpayers—they need to support the state’s adaptation and funding measures. Therefore, this study investigates the climate change and forest dieback perception of local inhabitants in two mountain areas of Southern Germany (the German Alps and the Bavarian Forest) with a quantitative survey based on representative online samples (n = 709). Relying conceptually on van der Linden’s (J Environ Psychol 41:112–124, 2015. https://doi.org/10.1016/j.jenvp.2014.11.012) climate change risk perception model, the results show that experiential processing, cognitive and socio-cultural factors are related to locals’ forest dieback and climate change perception, while socio-demographics show no or few connections. Nearly two-thirds (64.7%) of the respondents perceive moderate to strong forest dieback, while more than half (55.0%) of the respondents already observe consequences of climate change. The perceptions of climate change and forest dieback are positively correlated with medium to high strength. This shows that forest dieback could be interpreted as an indicator of climate change, which is difficult to observe due to its long-term nature. We identify three groups of respondents regarding preferred forest adaptation strategies to climate change. In general, respondents support nature-based forest adaptation strategies over intense measures.
Toarciconiopteryx dipterosimilis gen. et sp. nov. is described from the Lower Toarcian of Grimmen (Western Pomerania, Germany) based on a hind wing. This enigmatic wing superficially resembles a dipteran forewing, but analysis in detail establishes that it belongs to the Neuroptera. We assign it to the Coniopterygidae with great confidence by its great concordance with the hind wings of that family, but a small possibility remains that it might belong to the Dipteromantispidae, although the very derived haltere-like hind wings of all its known members are entirely unlike it. We, therefore, consider it to be the oldest record of Coniopterygidae. We create the new subfamily Toarciconiopteryginae subfam. nov. for it, which is distinguished from other Coniopterygidae by its hind wings possessing two branches of RP and a proximal forking of M. These conditions are also known in some Sialidae (Megaloptera), supporting the hypothesis that Coniopterygidae is the sister group of all other Neuroptera, as Megaloptera is considered by most authors to be sister to Neuroptera. New interpretations of some aspects of the Coniopterygidae venation are proposed.
Peatlands contribute to a wide range of ecosystem services. They play an important role as carbon sinks in their natural state, but when they are drained, they cause carbon emissions. Rewetting drained peatlands is required to reduce carbon emissions and create new carbon sinks. However, drained peatlands are commonly used as grassland or croplands; therefore, alternative agriculture schemes are required following rewetting. Paludiculture, i.e., agriculture on wet and rewetted peatlands, is an option in these areas after rewetting to produce biomass sustainably. Monitoring of peatland management is challenging, yet needed to ensure a successful rewetting and plantation of, e.g., Phragmites australis and Typha spp., two plants which are commonly used in paludiculture. Remote sensing is an excellent tool for monitoring the vegetation composition of vast rewetted peatland regions. However, because many peatland species have similar spectral characteristics, such monitoring is ideally based on high-spatial, high-temporal hyperspectral images. Data that complies with all these requirements does not exist on a regular basis. Therefore, we assessed the potential for mapping peatland vegetation communities in the Peene and Trebel river basins of the federal state of Mecklenburg-Western Pomerania, Germany, using multi-date hyperspectral (PRISMA) data. We used regression-based unmixing to map fractions of different peatland vegetation classes. Results were analyzed with regard to the contribution of multi-date observations and, in comparison, to multispectral datasets (Landsat-8/Sentinel-2). Our results showed that different classes are best mapped at different observation dates. The multi-date hyperspectral datasets produced less Mean Absolute Error (MAE = 16.4%) than the single-date hyperspectral images (ΔMAE + 1%), with high accuracies for all classes of interest. Compared to the results obtained with multispectral data from similar acquisition dates and annual spectral-temporal metrics (STM), the results from hyperspectral data were always clearly superior (ΔMAE + 4%). Besides the superior performance during comparisons, our results also indicate that information that can be derived from the hyperspectral data with the regression-based unmixing goes clearly beyond that of discrete classification. With more hyperspectral sensors coming up and an expected higher availability of multi-data hyperspectral imagery, these data can be expected to play a bigger role in the future monitoring of peatlands.
Monitoring and assessing groundwater quality according to European directives and national regulations is usually based on interpolation techniques, e.g. Kriging. However, contour maps of hydrochemical parameters often suggest a spurious local accuracy and can therefore lead to inappropriate action measures. Here, the early concept of extension variance combined with the Voronoi tessellation regionalization is proposed. The mosaic-like representation of pollutant concentrations in Voronoi polygons avoids misinterpretations caused by interpolation. The additional calculation of the extension variance, which is based on fundamental geostatistical assumptions, allows for estimating the probability that a given threshold is exceeded. This concept is further extended to hydraulically delimitable groundwater bodies, thus ensuring that hydraulic boundaries are considered. A method is here described for the assessment of groundwater quality with respect to nitrate concentration in the principal aquifer of the state Mecklenburg-Western Pomerania in Germany.
The reduction of individual carbon consumption could make an important contribution to the worldwide effort to limit global warming. Based on Bandura’s theory of moral disengagement, we hypothesized that the propensity to morally disengage concerning high-carbon behaviors (e.g., eating meat or traveling by plane) is one important factor that prevents individuals from reducing their carbon footprint. To measure the propensity to morally disengage in high-carbon-related behavior contexts, a questionnaire (MD-HCB) was developed and psychometrically validated in an online study with a German sample (N = 220). Confirmatory factor analyses revealed that the final nine-item scale had a one-dimensional structure, as intended. The internal consistency of the scale was excellent (Cronbach’s α = 0.94) and the scale interpretation had predictive validity for both past low-carbon consumption behavior and the intention to engage in such behavior in the future. Correlational analyses with relevant existing instruments confirmed the construct validity of the interpretations that can be drawn from the MD-HCB, as its resulting score is related to, yet separable from, the general tendency to morally disengage and is meaningfully connected to related constructs. A pre-study with a student sample (N = 89) not only helped to identify limitations in the study design but also showed a weak predictive ability of moral competence concerning high-carbon consumption behavior and intention to change. Based on our findings, future media campaigns designed to increase people’s intention to reduce high-carbon behavior could focus on the modification of common cognitive disengagement strategies.
The multi-level perspective has been criticized for being functionalistic and paying little attention to actor-based perspectives. Nevertheless, for the identification and assessment of potential change agents in a sustainability transition, a clear conceptual and methodological approach is necessary. This paper, thus, develops a multi-dimensional typology of niche, regime, and hybrid actors, which is conceptually grounded in transition studies and empirically illustrated by a cluster analysis based on a survey of pig and poultry farmers in Germany, France, and the Netherlands. Animal husbandry is chosen as a case study because a significant share of the environmental impact within the agri-food system is attributed to this sector and there is evidence for resistance to change by mainstream actors. Conceptually, the paper provides a framework of constitutive elements for different kinds of actors and contributes to an extension of the niche–regime dichotomy by adding the group of hybrid actors. The empirical results show that cluster analysis is a suitable approach to identify conceptually meaningful differences among interviewed farmers. Among pig and poultry farmers, the regime actors are by far the largest group. The smaller group of hybrid actors, however, has large potential to act as boundary spanners. A particularly interesting finding is that several larger farms are among the group of niche actors which hints at the possibility that larger farms are not necessarily resistant to change.
The occurrence and distribution of organochlorine pesticides (OCPs) in aquatic systems is a matter of global concern and poses significant toxicological threats to both organisms and human health. Despite the extensive use of OCPs for pest and disease control in southern Africa, relatively few studies have examined the occurrence and toxicological risks of OCP residues in the region. This study investigates the composition, distribution, and potential sources of OCP contamination in sediments from Richards Bay, a rapidly developing industrial port on the northeast coast of South Africa. Surface sediments collected from Richards Bay Harbour and surrounding areas indicate that OCP contamination in the region is widespread. Total concentrations (∑OCP) in surface samples ranged from 135 to 1020 ng g−1, with hexachlorocyclohexanes (∑HCH; 35–230 ng g−1) and dichlorodiphenyltrichloroethanes (∑DDT; 12–350 ng g−1) the dominant contaminant groups detected. Metabolite isomeric compositions indicate that the presence of aldrin and endosulfan likely result from historical agricultural usage, while recent input of γ-HCH, heptachlor, and endrin may be linked to the illegal use of old pesticide stockpiles. Total DDT concentrations were dominated by p,p′-DDT (80 ± 64 ng g−1), which was attributed to its ongoing use in malaria vector control in the region. A 210Pb-dated sediment core revealed that OCP input to the local environment increased dramatically from relatively low concentrations in the mid-1940s (∑OCP, 355 ng g−1) to peak levels (∑OCP, 781 ng g−1) in the 1980s/1990s. An overall decrease in ∑OCP concentration from the mid-2000s is likely related to restrictions on use following the Stockholm Convention in 2004. Despite current restrictions on use, OCP concentrations exceeded sediment quality guidelines in the vast majority of cases, raising concerns for protected estuarine and mangrove habitats in the area, as well as for local fishing and farming communities.
Thermally treated kaolinite is used to develop a range of alumino‐silicate‐based precursor materials but its behavior during plasma spraying has not been well‐researched. In this study, two types of kaolinite samples were investigated in the form of low defect (KGa‐1b) and high defect (KGa‐2) varieties. The extreme temperatures of the plasma stream (up to 20 000 K) induced flash melting to produce a highly porous alumino‐silicate glass without any crystallization of new Al−Si oxide minerals. The glass is comprised largely of intact or deformed spheres (average diameters 1.14–1.44 μm), which indicates rapid quenching and solidification before impact. The subspherical structures contain up to 40 % closed pore space caused by the rapid escape of water during melting. The low‐density, porous alumino‐silicate glass coatings with predicted specific surface areas (>0.95 m2/g) and hardnesses >1.8 GPa represent a potentially reactive but physically stable substrate ideal for further chemical functionalization.
Late Pleistocene glacitectonism at the southern Scandinavian Ice Sheet margin caused folding and thrusting of Upper Cretaceous chalk layers and Pleistocene glacial deposits in parts of the southwestern Baltic Sea area in Europe. Beside Møns Klint (SE Denmark), the Jasmund Glacitectonic Complex (JGC) on Rügen Island (NE Germany) is a similar striking example of glacitectonic deformation creating large composite ridges. In spite of a long research history and new results from modern datasets, the structural development of the JGC is still poorly understood, especially the detailed evolution of the southern JGC and its relationship to the northern JGC remain enigmatic. In this contribution, we demonstrate how the understanding of the JGC benefits from the application of established structural geological methods comprehending the formation of fold-and-thrust belts. The methods include cross-section balancing of the eastern coast (southern JGC) and quantification of the amount of folding and faulting. The proposed geometric model shows the current fold-and-thrust stack of glacially deformed sedimentary strata ca. 5720 m in length evolved by shortening from the original length (11,230 m) by 5510 m (49.1%). We present a spatial and temporal development of fault-related folding with a transition from detachment folds through fault-propagation folds to fault-bend folds. Together with morphological information from a digital elevation model, the thrust faults mapped in the cliff section are mainly inclined towards the S to SW and imply that a local glacier push occurred from the south. These results highlight the complexity and individual architecture of the JGC when compared to other Pleistocene and modern glacitectonic complexes. Resolving its structural development provides new insight into the deformation history and shortening of this spectacular glacitectonic complex lying in the southwestern Baltic Sea region.
There is a current need for developing improved synthetic porous materials for better constraining the dynamic and coupled processes relevant to the geotechnical use of underground reservoirs. In this study, a low temperature preparation method for making synthetic rocks is presented that uses a geopolymer binder cured at 80 °C based on alkali-activated metakaolin. For the synthesised sandstone, the key rock properties permeability, porosity, compressive strength, and mineralogical composition, are determined and compared against two natural reservoir rocks. In addition, the homogeneity of the material is analysed structurally by micro-computed tomography and high-resolution scanning electron microscopy, and chemically by energy dispersive X-ray spectroscopy. It is shown that simple, homogenous sandstone analogues can be prepared that show permeability-porosity values in the range of porous reservoir rocks. The advance in using geopolymer binders to prepare synthetic sandstones containing thermally sensitive minerals provides materials that can be easily adapted to specific experimental needs. The use of such material in flow-through experiments is expected to help bridge the gap between experimental observations and numerical simulations, leading to a more systematic understanding of the physio-chemical behaviour of porous reservoir rocks.
Calcitic valves of non-marine ostracodes are important geochemical archives. Investigations of the relationship between the ranges of oxygen and carbon isotope values of modern ostracode populations and their host water provide important information on local or regional conditions and influences. Here we present the first δ18Oostracode and δ13C of the freshwater ostracode species Cytheridella ilosvayi along with the isotopic composition of the waters in which the ostracodes calcified, δDwater, δ18Owater, δ13CDIC values—covering a large geographical range (Florida to Brazil). With this data we extended a newly developed approach based on the estimation of δ18O values of monthly equilibrium calcites as references for the interpretation of δ18Oostracode values. The expected apparent oxygen isotope fractionation between CaCO3 and H2O is correlated with temperature with smaller values occurring at higher temperatures as valid at isotope equilibrium (δ18Ocalcite_eq). Uncertainties about the expected equilibrium calcites derive from incomplete knowledge of high-frequency variations of the water bodies caused by interplay of mixing, evaporation, and temperature. Coincidence between δ18Oostracode and δ18Ocalcite_eq is restricted to few months indicating a seasonal calcification of Cytheridella. There is a characteristic pattern in its difference between mean δ18Oostracode and δ18Ocalcite_eq which implies that Cytheridella provides a synchronous life cycle in its geographical range with two calcification periods in spring (May, June) and autumn (October). This ubiquitous life cycle of Cytheridella in the entire study area is considered to be phylogenetically inherited. It might have originally been adapted to environmental conditions but has been conserved during the migration and radiation of the group over the Neotropical realm.
There is broad scientific consensus that current food systems are neither sustainable nor resilient: many agricultural practices are very resource-intensive and responsible for a large share of global emissions and loss of biodiversity. Consequently, current systems put large pressure on planetary boundaries. According to economic theory, food prices form when there is a balance between supply and demand. Yet, due to the neglect of negative external effects, effective prices are often far from representing the ‘true costs’. Current studies show that especially animal-based foodstuff entails vast external costs that currently stay unaccounted for in market prices. Against this background, we explore how informational campaigning on agricultural externalities can contribute to consumer awareness and tolerance of this matter. Further, we investigate the socially just design of monetary incentives and their implementation potentials and challenges. This study builds on the informational campaign of a German supermarket displaying products with two price tags: one of the current market price and the other displaying the ‘true’ price, which includes several environmental externalities calculated with True Cost Accounting (TCA). Based on interpretations of a consumer survey and a number of expert interviews, in this article we approach the potentials and obstacles of TCA as a communication tool and the challenges of its factual implementation in agri-food networks. Our results show that consumers are generally interested in the topic of true food pricing and would to a certain extent be willing to pay ‘true prices’ of the inquired foods. However, insufficient transparency and unjust distribution of wealth are feared to bring about communication and social justice concerns in the implementation of TCA. When introducing TCA into current discourse, it is therefore important to develop measures that are socially cautious and backed by relevant legal framework conditions. This poses the chance to create a fair playing (‘polluter pays’) with a clear assignment of responsibilities to policy makers, and practitioners in addition to customers.
Circular economies are an important pillar of sustainable production and consumption. This particularly applies to the agri-food industry, which is characterised by large amounts of organic waste and by-product streams posing a serious challenge for many food producers. Therefore, respective firms increasingly adopt circular economy business models (CEBMs) to manage these resource flows effectively. However, there is only little knowledge on the functioning of CEBMs in bio-based industries, especially from a socio-economic perspective. We address this gap by exploring enablers and motivations behind such business models as well as the institutional contexts they are embedded in. In methodological terms, we adopt a case study approach using the example of potato production in Lower Saxony (northwest Germany). The core of the paper is a qualitative in-depth analysis of four potato processors, adopting varying business models to valorise their by-product streams (e.g. peels, scraps, pulp) either ‘in-house’ or in partnerships with external partners. The findings show that the implementation of CEBMs results from a complex interplay of internal and external enablers, with economic considerations as the main impetus for the management of biological reverse cycles. Thereby, we found a shifting economic logic in the assessment of potato by-products from disposable waste to valuable resources for other sectors (e.g. livestock farming, bioenergy, biofuels). While being encouraged by targeted policies, the companies studied feel increasingly affected by emerging sustainability discourses, prompting them to (re)design and (re)frame their CEBMs in view of environmental and societal issues.
Thyreophora is a clade of globally distributed herbivorous ornithischian dinosaurs. The earliest forms are known from the Early Jurassic, and their latest surviving representatives witnessed the end-Cretaceous mass extinction. Throughout their evolutionary history, these ‘shield bearers’ became lumbering quadrupeds, evolved a wide array of bony armor, plates and spikes, as well as sweeping tail weapons in the form of tail clubs and thagomizers. An isolated new thyreophoran osteoderm from a Lower Jurassic Konservatlagerstätte near Grimmen is described and, with the aid of micro-CT data, compared to an osteoderm of the early diverging thyreophoran Emausaurus ernsti from a different stratigraphic horizon at the same locality.
Diagenetic illite growth in porous sandstones leads to significant modifications of the initial pore system which result in tight reservoirs. Understanding and quantifying these changes provides insight into the porosity-permeability history of the reservoir and improves predictions on petrophysical behavior. To characterize the various stages of diagenetic alteration, a focused ion beam – scanning electron microscopy (FIB-SEM) study was undertaken on aeolian sandstones from the Bebertal outcrop of the Parchim Formation (Early Permian Upper Rotliegend group). Based on 3D microscopic reconstructions, three different textural types of illite crystals occur, common to many tight Rotliegend sandstones, namely (1) feldspar grain alterations and associated illite meshworks, (2) tangential grain coats, and (3) pore-filling laths and fibers. Reaction textures, pore structure quantifications, and numerical simulations of fluid transport have revealed that different generations of nano-porosity are connected to the diagenetic alteration of feldspars and the authigenic growth of pore-filling illites. The latter leads to the formation of microstructures that range from authigenic compact tangential grain coatings to highly porous, pore-filling structures. K-feldspar replacement and initial grain coatings of illite are composed primarily of disordered 1Md illite whereas the epitaxially grown illite lath- and fiber-shaped crystals occurring as pore-filling structures are of the trans-vacant 1Mtv polytype. Although all analyzed 3D structures offer connected pathways, the largest reduction in sandstone permeability occurred during the initial formation of the tangential illite coatings that sealed altered feldspars and the subsequent growth of pore-filling laths and fibrous illites. Analyses of both illite pore-size and crystallite-size distributions indicate that crystal growth occurred by a continuous nucleation and growth mechanism probably controlled by the multiple influx of potassium-rich fluids during late Triassic and Jurassic times. The detailed insight into the textural varieties of illite crystal growth and its calculated permeabilities provides important constraints for understanding the complexities of fluid-flow in tight reservoir sandstones.
Ocean literacies: the promise of regional approaches integrating ocean histories and psychologies
(2023)
The current concept of ocean literacy reflects a prerequisite for achieving ocean sustainability. Existing ocean literacy reflects a fundamentally western view of oceans that works in tension with ocean literacy goals. Although ocean literacy practitioners and researchers are, laudably, starting to incorporate Indigenous knowledges and perspectives from BIPOC communities, attention to historical change continues to be left out of ocean literacy, to the detriment of ocean literacy goals. This article points out that, given the reality that human-ocean relationships have changed over time, and differed among cultural groups in the past as well as in the present, ocean literacy needs to incorporate ocean history at a foundational level. Because there are historical differences in human relationships with oceans, it stands to reason that regional ocean literacies must be more effective than a universal and timeless ocean literacy framework. Following the logical efficacy of a regional approach to ocean literacy, this article further argues that regional ocean literacies should involve the systematic inclusion of emotional elements. Regional ocean literacies should be constructed through knowledge co-production, involving diverse types of expertise, knowledge and actors to produce context-specific knowledge and pathways towards a sustainable future. To fully exploit the potential of ocean literacy, there is a need for the UN Ocean Decade to work towards regional and place-based approaches that incorporate history as well as culture in an iterative and collaborative process involving diverse types of expertise, knowledge and actors.
Giant clam (Tridacna) distribution in the Gulf of Oman in relation to past and future climate
(2022)
The Oman upwelling zone (OUZ) creates an unfavorable environment and a major biogeographic barrier for many coral reef species, such as giant clams, thus promoting and maintaining faunal differences among reefs on the east and west side of the Arabian Peninsula. We record the former existence of Tridacna in the Gulf of Oman and review its stratigraphic distribution in the Persian Gulf to provide new insights on the connectivity of coral reef habitats around southern Arabia under changing climate and ocean conditions. Fossil shells were carbon-14 dated and employed as sclerochronological proxy archives. This reveals that the Omani population represents a last glacial colonization event during the Marine Isotope Stage 3 interstadial under colder-than-present temperatures and variable upwelling intensity linked to Dansgaard-Oeschger climate oscillations. It was favored by temperatures just above the lower threshold for the habitat-forming reef coral communities and instability of the upwelling barrier. We conclude that the distribution of Tridacna in the northern Arabian Sea is generally limited by either strong upwelling or cool sea surface temperature under gradually changing climate conditions at the interglacial-glacial scale. Opportunities for dispersal and temporary colonization existed only when there was a simultaneous attenuation of both limiting factors due to high-frequency climate variability. The OUZ will unlikely become a future climate change refuge for giant clams because they will be exposed either to thermal stress by rapid anthropogenic Indian Ocean warming or to unfavorable upwelling conditions.
Global change is one of the major challenges our society faces in recent times and is becoming increasingly noticeable in all aspects of our lives. In the last ten years, reports about droughts in Europe increased, contrary to expected natural climate variations and are attributed as indicators of climate change. Droughts resulted in a severe decrease in water levels of lakes, rivers and reservoirs, posing socio-economic and environmental challenges. Climate scenarios by the Intergovernmental Panel on Climate Change (IPCC) project increasing temperatures, more frequent, longer and/or more intense heat waves and warm spells, and an increase in aridity with short-term droughts in the upcoming decades for Western and Central Europe. Some areas – such as Northeast Germany – are already affected by negative water balances and the lowering of lake and groundwater levels. Additionally to possible challenges in water availability, excess nutrients and heavy metals from industrial emissions, agricultural fertilisers and land use changes lead to declining water quality. In the past century, extensive eutrophication and environmental pollution have become major water quality issues in many freshwater bodies.
Nonetheless, water and its availability in a sufficient quantity and quality are prerequisites for life and must be prioritised in future development. The European Union aims for a good status in all surface and groundwater bodies by 2027 regarding their ecological, chemical and quantitative status. However, a profound understanding of eutrophication, pollution sources, and water bodies' reference conditions – referring to pre-anthropogenic conditions – should be available for each system to apply integrated restoration strategies. Moreover, an in-depth understanding of long-term climate variability and its dynamics is indispensable to approach these climate change challenges and reliably predict water availability.
During the past decades, numerous paleoenvironmental studies have been carried out on Northern German sediment archives, using mainly lacustrine sediments to reconstruct hydroclimatic variability, often inferring lake-level variations as key indicators. However, most studies were carried out in areas affected by more maritime or continental climate. Studies from the transition zone are rare. Only few existing studies offer high-resolution records and/or robust chronologies, which limits the understanding of past environmental changes significantly. Besides, the Northern German lowlands have been anthropogenically affected since at least the Neolithic (~5.6 ka cal BP) and, in particular, forest composition and density have recently been shown to have at least partially an impact on lake-level variations. However, a reliable distinction between climatic impacts and anthropogenic interferences is widely missing, which is a problem because many studies were conducted on rather small lacustrine systems in which expected anthropogenic signals are higher, and single events may overprint the climatic signals. These biases lead to an incoherent picture of the past hydroclimatic variability in Northern Germany during the Holocene. To overcome this situation, it is inevitable to identify a suitable sedimentary archive from the transition zone – preferably a large lacustrine system in which natural (supra-)regional paleoenvironmental signals are expected to be not overprinted by single events. Moreover, it is necessary to establish robust chronologies and apply high-resolution methods to infer past environmental changes in a high temporal resolution. Taken together, this could contribute to an enhanced understanding of past environmental and climatic changes in Northern Germany.
This thesis consolidates the evidence for Schweriner See to act as a suitable sedimentary archive in Northern Germany for (supra-)regional climate reconstructions. Schweriner See is a large lowland lake in Northern Germany located within the transition zone from maritime to continental climate. In the first step, (paleo)lacustrine landforms, i.e. beach ridges, subaerial nearshore bar, and a silting-up sequence, are investigated along the north-eastern shoreline using a combined approach of sedimentology (e.g. grain size variations) and the relatively novel method of luminescence profiling offering relative age determinations to understand depositional processes and their chronological framework. Absolute age information is mainly inferred by OSL dating. Secondly, an important prerequisite to interpreting information obtained from lacustrine sediment archives is a thorough understanding of processes controlling sedimentation. Schweriner See is characterized by a complex morphometry, which influences in-lake processes, i.e. i) in-lake productivity, ii) carbonate precipitation and iii) wind- and wave-induced processes, resulting in a distinct spatial heterogeneity. This thesis shows that it is crucial first to understand sedimentary depositional processes and controlling mechanisms to i) select suitable coring location(s) and ii) reconstruct paleoenvironmental and hydroclimatic variations reliably.
Based on bathymetric considerations and inferred in-lake processes, two main coring locations were identified to infer i) the anthropogenic impacts and ii) hydroclimatic variations. Short sediment records from the shallow water areas (< 15 m water depth) cover the most recent environmental history of Schweriner See. A well-dated sedimentary record (210Pb/137Cs and 14C dating) links distinct sedimentary and geochemical changes with historical events. Schweriner See was extensively affected by lake-wide eutrophication and contamination, closely related to sewage and population dynamics within the catchment. The water quality only improved after the German Reunification in 1990 CE when sewage was precluded from Schweriner See. Contamination trends at Schweriner See showed similar trends to different archives along the southern Baltic Sea, implying a common regional driving mechanism, e.g. environmental legalisation.
A well-dated sediment record from the profundal zone (52 m water depth) allowed the reconstruction of large-scale atmospheric conditions during the past 3 ka cal BP by inferring winter temperature variability, the moisture source region and/or evaporative lake water enrichment, which resemble variations in the North Atlantic Oscillation (NAO). The NAO greatly influences the Central European climate, affecting, for example, surface air temperature, precipitation or storm tracks. During 3-2.8 ka and 2.1-0.8 ka cal BP, predominantly positive NAO conditions are reconstructed, which are characterized by warmer winter temperatures, moisture conditions bringing isotopically enriched precipitation from the southern/central North Atlantic to Northern Central Europe and/or warmer temperatures that may result in a higher evaporative isotopic lake water enrichment as a result of northwards displaced westerlies. Conversely, during 2.8-2.1 ka and 0.8-0.1 ka cal BP, results correspond to predominantly negative NAO phases influenced by southwards displaced westerlies. Frequent atmospheric blocking allows for the intrusion of northerly or easterly winds, resulting in colder winter temperatures, isotopically depleted precipitation from the Northern Atlantic and Arctic region and/or a lower evaporative lake water enrichment. In addition to these long-term changes in atmospheric conditions, short-term hydroclimatic variations have been reconstructed, mainly reflecting lake-level variations in conjunction with precipitation variability, with the proxy signal being additionally amplified by wind speed and wave motion. Comparisons with other archives support these results.
So far, the paleoenvironmental reconstruction is limited to the Late Holocene, but initial dating results imply possible interferences until the Late Pleistocene. Therefore, future studies should focus on extending the profundal record from Schweriner See further back in time, providing a high-resolution record covering both the Holocene and possibly the Late Pleistocene.
Based on extensive investigations along the coast and in the coastal waters of NE Germany, a lithostratigraphic classification of the Holocene coastal deposits is presented. Their characteristics, i.e. the lithofacies, reflect the spatial change in hydrodynamics, sediment supply, salinity, bioproduction, etc. in the accumulation space. The displacement of the facies associated with the sea-level rise of the Baltic Sea led to the formation of regularly occurring vertical depositional sequences. From these regular profiles, four lithostratigraphic formations and two subformations of the coastal deposits can be delineated as approximately homogeneous sedimentary bodies, which are described in detail, defined in terms of their spatial extent and classified with regard to the time of accumulation.
The exchange of water and dissolved elements between the continents and the oceans occurs via different routes in the hydrological cycle, such as rivers, atmospheric exchange, and submarine groundwater discharge (SGD). In addition, the elemental fluxes in the coastal waters may strongly depend on benthic water-solid-microbe interactions close to the sediment-water interface. It is becoming increasingly recognized that SGD can impact diagenesis and act as a source of water and dissolved substances for coastal ecosystems. The qualitative and quantitative assessment of SGD is still challenging as it requires the identification of suitable geochemical tracers for the complex hydrological and biogeochemical processes in the subterranean estuary. In this study, geochemical analyses were combined with geophysical, hydrological, and biological investigations to gain insights into the mechanisms driving SGD in coastal waters. In addition, onshore ground and surface waters were evaluated to identify the processes controlling the potential end member. The surveys were performed along the Baltic Sea coast: Warnow River and Wismar Bay in Germany, the Gulf of Gdańsk and Puck Bay in Poland, and Hanko Bay in Finland. The results suggest that the analyzed surface water system was strongly impacted by seasonal variations, while SGD displayed a much more stable composition throughout the year. New areas of SGD were also identified along the Baltic Sea. It was also observed that anthropogenic coastal infrastructures could promote SGD affecting the water balance and the benthic fluxes. At other sites, the SGD was associated with natural structures such as pockmarks. The stable isotopic composition of the fresh component of SGD was close to the meteoric water at most sites; however, old groundwaters from distinct aquifers were identified. Combining all sites, SGD showed high variability, ranging from near 0 to up to 300 L m-2 d-1, and the saline SGD was more dominant than the fresh component. The fluxes obtained at one site were even higher than the surface runoff. SGD was higher on sandy sediments, but the elemental fluxes were relatively low. Despite low SGD at muddy sites, interfacial elemental fluxes, enhanced by intense diagenesis in the top sediments, resulted in higher chemical fluxes to the water column. The sediment porewater gradients at the SGD impacted sites suggest that the advective upward flow of groundwater increased the elemental fluxes across the sediment-water interface. Therefore, the dissolved substances of SGD are partly impacted by the processes in the soil zone and aquifer during groundwater development, and partly impacted by the early diagenetic process in the surface sediments. Overall, this study shows the importance of SGD for the biogeochemical cycles of coastal waters. Moreover, 6 it can be concluded that a combination of interdisciplinary approaches can provide a better understanding and assessment of SGD in a specific environment. Although all the studies presented here are local, the methodology and results presented in this thesis can be replicated and thus provide assistance in other coastal areas.
Autoclaved aerated concrete (AAC) is a building material that combines heat insulation
properties with sufficient mechanical strength for masonry construction. Compared to
ordinary concrete, the matrix is highly porous (>50%) and hardened by a hydrothermal curing
process at 150°C - 200°C. During this process, quartz sand and portlandite react to form first
calcium silicate hydrates (C-(A)-S-H) with Ca/Si ratios <1.3 and then tobermorite. Especially
tobermorite, which has a much larger crystallite size than C-(A)-S-H, provides improved
mechanical strength. This reaction sequence is influenced by many parameters and
additives of which calcium sulfate is probably the most important. Despite several attempts to
investigate these hydrothermal reactions, the actual reaction mechanism involved when
adding sulfate ions is not fully understood. It has been suggested that the addition of ca.
1.5 wt% significantly improves the mechanical properties due to the enhanced formation and
arrangement of tobermorite in the porous matrix. Since the sulfate content in AAC waste is
exceeding regulatory threshold for low-quality reuse in some countries, the aim of this study
was to investigate in detail the reaction mechanisms involving sulfate addition. Such
knowledge may open up the possibility to improve AAC production and to avoid the need for
sulfate addition. To achieve this goal, this research work focused on investigating the
hydrothermal curing process to determine the sequence of hydrothermal reactions and the
spatial distribution of the phases formed. For this purpose, a new setup for in situ X-ray
diffraction was specifically designed to study hydrothermal reactions and to conduct time
intensive experiments on a normal laboratory diffractometer. In order to quantitatively
evaluate the in situ measurements by Rietveld analysis using TOPAS, it was also necessary
to develop atomistic structure models for C-(A)-S-H phases. This was made possible by
adopting a supercell approach that was previously used to describe turbostratically stacked
clay minerals. The structure models, derived from tobermorite, are placed in an otherwise
empty supercell to simulate the C-(A)-S-H nanostructure. Adopting these methodological
advances, it was possible to obtain absolute phase quantities from in situ data and to track
the reaction kinetics of the hydrothermal curing process. These results were then combined
with ex situ X-ray diffraction and scanning electron microscopy. Confirming previous studies,
the major effect of sulfate ions was the formation and decomposition of hydroxylellestadite. It
was further revealed that C-(A)-S-H formation was delayed during hydroxylellestadite
formation, which is supposed to support the silicate ion diffusion and hence the tobermorite
formation at a stage critical for improved hardening of AAC. This can be linked to the
formation of lower amounts of capillary pores in the range of 1-5 µm, as observed by
scanning electron microscopy, and therefore a lower concentration of inherent defects that
resulted in the improved mechanical properties. This research work highlights how important the spatial distribution of crystallites is for the properties of a building material and how this
distribution can be influenced by small alterations in reaction chemistry.
The deep geological underground represents an important georesource for the short-
term storage of renewable energy and the long-term reduction of greenhouse gas emissions. To ensure the economic viability and safety of any subsurface storage project, detailed characterisation of the quality and integrity of the reservoir and its cap rock is required. This characterisation includes the accurate determination of the petrophysical properties, such as porosity and permeability, as well as the potential mineral reactions, such as the dissolution of reactive phases, which may occur during the lifespan of such a project. Clay minerals are common components of many reservoir systems and, depending on their type and structure, can have a significant impact on storage and transport properties. These processes are, however, currently not well understood. In order to address these issues, the main focus of this thesis is on mineralogical analyses using X-ray diffraction (XRD) and microstructural studies using focused ion beam scanning electron microscopy (FIB-SEM) together with micro X-ray computed tomography (µXCT) to gain a better understanding of the influence of clay minerals on reservoir and cap rock properties.
A central part of this thesis focuses on the analysis of clay minerals and pore structures of the Bebertal Sandstone of the Parchim Formation (Early Permian, Upper Rotliegend), which is considered a natural analogue for the tight reservoir sandstones of the North German Basin. Two illite polytypes with a variety of characteristic structures have been identified in the Bebertal sandstone. Disordered 1Md illite forms the majority of the observed structures, which include omnipresent grain coatings, altered permeable feldspar grains and pore-filling meshwork structures. Trans-vacant 1M illite represents the second and youngest generation of authigenic illite and occurs as fibrous to lath-shaped particles that grew into open pore spaces and led to a significant reduction in porosity and permeability during late diagenesis. Based on these results, a model for the formation of illite polytypes in the aeolian layers of the Bebertal sandstone was developed that describes the temporal and spatial evolution of porosity and permeability during diagenesis. Information from this model was then used to improve the prediction of permeability of the Bebertal sandstone based on µXCT pore space models and direct numerical simulations. To achieve this, a micro-scale pore space model was created that allowed the simulation of permeability reduction by clay minerals by including nanoporous illite domains based on a novel morphological algorithm. By performing Navier-Stokes-Brinkman simulations, more accurate predictions of permeabilities with respect to experimentally determined values were obtained compared to conventional Navier-Stokes simulations.
The detailed characterisation of the Bebertal sandstone has shown that natural reservoir rocks are usually complex heterogeneous systems with small-scale variations in texture,
composition, porosity and permeability. Flow-through experiments on the Bebertal sandstone revealed that the coupled geochemical and hydrodynamic processes that occur during the dissolution of calcite could not be predicted by reactive transport models. Therefore, as part of this thesis, a novel approach for developing synthetic sandstones at low temperatures based on geopolymer binder was developed. It is shown that simpler and more homogeneous porous materials can be produced with porosity and permeability values in the range of natural sandstones. These can be used to better understand the dynamic and coupled processes relevant to the storage of renewable energy in reservoir rocks through improved experimental constraints.
The final part of this thesis reports on a detailed clay mineral and pore space study of
three shale formations and one mudstone that were identified as potential seals for the Mt. Simon sandstone reservoir in the Illinois Basin. During the Illinois Basin - Decatur Project, this reservoir was used for the sequestration of one megaton of supercritical carbon dioxide. In order to better assess the quality of the sealing units and to better understand the role of the intergranular clay mineral matrix as potential pathway for fluid migration, a multi-scale evaluation was conducted that included thin section analysis, quantitative evaluation of minerals by scanning electron microscopy (QEMSCAN), mercury intrusion capillary pressure (MICP) measurements, quantitative XRD and high-resolution FIB-SEM. The results allow for the classification of the studied formations into primary and secondary seals and emphasise the importance of three-dimensional clay-mineral-related pore structure characterisations in cap rock studies. XRD proved the most reliable method for the identification and quantification of clay minerals in the studied cap rocks and mudstones. In contrast, FIB-SEM and QEMSCAN provided the spacial constraints for reconstructing fluid flow pathways within the clay mineral matrix.
Overall, this thesis highlights the importance of the precise identification of clay minerals in geological reservoirs and their cap rocks. It also illustrates the need for three-dimensional characterisation and modelling of the associated small pore structures for an improved understanding of the rocks diagenetic history as well as the prediction of the transport and storage properties of these crustal reservoir systems.
Underground hard coal mining operations irreversibly disrupt the pre-existing mechanical equilibrium of the geological media. The employment of high-recovery methods modifies the stress field of the sedimentary sequence, generating movement and faulting of the rock layers above and below mined seams. These new fracture zones do affect the original conditions of the hydrogeological system by modifying flow pathways and increasing the permeability of the rock sequence. Moreover, the surface area of rock exposed to air and water is increased, conditioning the water-rock interaction. Despite this rather clear conceptualization, flow and reactive transport processes in fractured overburdens are rarely modeled simultaneously. Discrete setups that consider fractures and porous matrix require extensive characterization of both media, which is impractical for regional case studies. As a result, most post-mining models explicitly ignore fracture structures by employing the equivalent porous approach or even both media with lumped parameter models. However, omitting either medium represents a delicate simplification, considering that mining-related fractures control the rate and direction of water flow within moderately permeable but relatively highly porous rock sequences.
In this dissertation, the specific contribution of fractured and matrix continua to the transient discharge and water quality of a post-mining coal zone is quantified and evaluated. For this purpose, dual and multiple interacting continua models are employed to simulate fluid flow and reactive mass transport in fractured and variable water-saturated rock sequences. The effectiveness of the models is evaluated by simulating the origin, generation and transport of acid mine drainage (i.e., water with elevated concentrations of hydrogen, iron, sulfate and chloride) within the shallow overburden of the Ibbenbüren Westfield. Compared to other coal districts in Germany, this area is strongly delimited by the local geology and topography, resulting in a well-defined hydrogeological system to test the models. Petrographic and chemical analyses performed on core samples from the area show the strong influence of mining-derived fractures on the water-rock interaction within the Carboniferous sequence. The presence of oxidized pyrite along with amorphous iron hydroxide phases in weathering fronts on both sides of the fractures demonstrates the exchange of solutes and gases between the fractured and the porous matrix media.
Based on the previous evidence, the TOUGHREACT software is employed to characterize flow and reactive transport processes in the Westfield. However, each of the two processes is simulated at separate stages to have more control in the adjustment of sensitive parameters for which little information is available. For the flow component, a dual continuum model, with Richard’s equations is used to characterize the unsaturated water flow in both fractured and matrix media. Under this approach, the model adequately reproduces the bimodal flow behavior of the discharges measured in the mine drainage for the years 2008 and 2017. Simulation results show how the fractured continuum generates intense discharge events during the winter months while the rock matrix controls smooth discharge limbs in summer, when water is slowly released back to the fractures. With the flow component calibrated, the second part of the study incorporates the geochemical processes into the model based on actual data from the rock samples. Their simulation requires extending the two-continuum setup to a multiple continua model with five nested block strings: one for the fractures and four for the rock matrix. This further subdivision prevents under-representations of kinetic reactions with short equilibrium length scales and numerical instabilities due to lack of chemical and flow gradients. As a result, the new multiple continua model provides good agreement with respect to long- and short-term concentrations and discharge trends measured in the mine drainage. The flow of oxygen and meteoric water through the fractured continuum leads to a high and steady release of hydrogen, iron and sulfate ions derived from pyrite oxidation in the matrix continua closest to the fractures. Moreover, high chloride concentrations result from the mixing and gradual release of relatively immobile solutes in the matrix as they interact with percolating water in the fracture. Both findings are equally congruent with the reactive pyrite oxidation and iron hydroxide precipitation fronts identified in the fractured core samples.
In the end, the multiple continua models, the simulation procedure and the results of the benchmark and sensitivity analysis scenarios developed for the Westfield pave the way for the application of the approach in other mining zones. The first candidate emerges in the Ibbenbüren Eastfield, where a coupled elemental-isotopic approach included in this thesis has confirmed that water-conducting fracture zones are primary elements for solute generation and transport in the first 300 meters of the overburden. In the latter case, calibration and verification of the models can be complemented with measurements of δ34S in sulfates and δ18O, δ2H, and Tritium in water.
The skull is an extremely informative part of the vertebrate body. Skulls are
involved to hunt, feed and drink, to nurse, fight, dig, and to many other activities.
Also, main sensory organs are situated on the head in order to enable a given
animal to see, smell, taste, feel, listen, equilibrate and think; hence, the head is the
main connection to the external world. It follows that a skull, with and without soft
tissue, can tell a lot about its owner. Each skull consists of many individual bones
constituting regions (e.g., snout and braincase) that represent different aspects of an
anatomical mosaic, which in turn allows deeper (palaeo)biological insights.
In the past three centuries, palaeontologists dug out countless fossils from all
over the world and from many preserved periods and groups, including dinosaurs.
Hence, public and private collections house numerous fossil skull specimens. To
further enlighten our understanding of palaeoecological, physiological and
phylogenetic affinities of dinosaurian representatives belonging to different groups,
and in order to reveal new aspects on their (neuro)anatomy, behaviour, ontogeny
and evolution, a thoroughly examination with modern techniques is the aim of this
thesis.
In order to get a phylogenetically broad understanding, fossil remains from at
least four extinct species, including Irritator challengeri (a theropod: mostly bipedal
carnivores) from the Early Cretaceous of northeastern Brazil, Europasaurus holgeri
(a sauropod: long-necked, quadrupedal herbivores) from the Late Jurassic of Lower
Saxony, Emausaurus ernsti together with an unnamed taxon from the Early Jurassic
of Mecklenburg-Western Pomerania, and Struthiosaurus austriacus, Late
Cretaceous of eastern Austria (the latter three are thyreophorans: armoured, mostly
quadrupedal herbivores), were in closer focus. To document and digitally reconstruct
cranial bones and cavities therein, the material was examined with micro computed
tomography (microCT). On this basis, the full morphology of the preserved anatomy
was revealed, described and contextualized, for example, in conjunction with
comparative anatomy and biomechanical considerations. During this process, further
methods were used to investigate and depict individual fossils: macro- and microphotography,
photogrammetry and phylogenetic analyses, each encompassing
multiple sub-tasks and being supported by 3D prints.
As part of the result, it was possible to formulate reasoned assumptions about
the lifestyle of the taxa in focus. For instance, the neuroanatomy and the osteological
characteristics of the spinosaurid Irritator challengeri implicate that this taxon was an
agile hunter with a habitually inclined snout that was specialized in catching relatively
small prey with a robust dentition and a comparably weak - but fast - bite, with a
remarkable jaw mechanism which enabled the animal to kinetically widen the
pharynx during lower jaw depression. The (neuro)anatomy of I. challengeri, S.
austriacus, E. ernsti and E. holgeri presented here, enrich our knowledge about a
plethora of (lifestyle-related) aspects of these animals, their closer relatives and the
prehistoric world they lived in.
Seas and oceans are essential for the global ecosystem. Entire societies, economies and countless livelihoods rely on their good environmental status. Yet, pressures on marine environments are increasing. An extensive assessment and monitoring of marine habitats is a vital precondition for understanding these systems and their sustainable conservation. Remote sensing methods can temporally accelerate the mapping, improve the spatial resolution and support the interpretation of large areas. Hydroacoustic becomes the method of choice for areas deeper than the coastal zone as optical signals are limited by strong attenuation in the water column. Apart from depth measurements for the creation of bathymetric charts, the recording of backscatter strength is useful for the characterization of the seafloor surface. The direct influence of the inhabiting benthic community on the backscattered signal is rarely considered, although it can be utilized for the detection of benthic life. Information about habitat-specific backscatter responses or a hydroacoustic remote sensing catalog for benthic habitats is missing so far.
The multibeam echosounder (MBES) has the advantage of recording both, bathymetry and backscatter strength simultaneously with related incidence angle. Further, recent technological developments allow to change between frequencies. Angular range curves supported the quantification of backscatter strength of different frequencies. Acoustic data sets were complemented by ground truthing in form of sedimentological and biological samples as well as video profiles. Study areas were located offshore the island of Sylt in the North Sea as well as in vicinity to Oder Bank and close to the coast offshore Hohe Düne/Rostock, both in the Baltic Sea. Investigated habitats included sand areas inhabited by tubeworms, loose mussel clusters on top of sand areas, seagrass meadows, coarse sand and gravel areas, and a reef covered by mussels.
Multifrequency backscatter maps, combining frequencies between 200 kHz and 700 kHz, illustrate small-scale features at the seafloor not visible in monofrequent maps. Key habitats showed a specific backscatter response, which can partly be related to macrobenthic flora and fauna. Data sets recorded with a (partly calibrated) MBES in three different month (May, August, October) revealed that backscatter strength can further detect spatial as well as temporal habitat dynamics. Alterations in the sediment composition at the seafloor surface of the ecologically valuable coarse sand and gravel areas were caused by seasonal changes in local hydrodynamics.
A newly developed 3D seismic lander has the ability to support hydroacoustic remote sensing as an additional, non-destructive ground truthing method utilizing a high frequency of 130 kHz to image the shallow subsurface. Buried objects, e.g., stones, shells, fruit gummy worms, as well as sediment disturbances could be detected and visualized in a laboratory experiment. The 3D seismic lander is likely to improve the investigation of volume scatter contribution to backscatter strength and is potentially applicable for the imaging of bioturbation.
This work first sets out to find if economic, ecological, or social incentives drive consumers towards or against dietary decisions (Contribution A). It then develops a framework of TCA for food to describe economically conveyed incentives that are tied to ecological and social indicators within the food market (Contribution B). The framework is subsequently enhanced and broadened to include a deeper understanding and broader field of indicators for more holistic TCA calculations (Contributions C and D). Lastly, based on these calculations, TCA of food is implemented in a factual use case as the framework and calculations are deployed for commodities of a German supermarket chain; then consumer, as well as expert feedback is used for the discussion on socially responsible campaigning and policy change (Contribution E).
The dissertation looks at bioeconomy innovation at different levels through the lens of economic geography. By progressing from the meta to the micro-scale, it tries to find answers to how the interrelated concepts of bioeconomy and innovation are embedded in these respective contexts while consecutively concretising bioeconomy and de-fuzzing it. To do that, it adopts a mixed-methods approach that starts general and ends specific, going from the meta-scale of literature over the macro-scale of three distinct areas in which bioeconomy is discussed to the meso-level of central actors of a European funding network before, lastly, considering case studies at the micro-scale. Throughout, the thesis aims to spatialise the bioeconomy by shedding light on the term and its drivers across multiple geographic layers. It thereby not only offers new insights into dimensions of innovation in the bioeconomy but also contributes to the discipline of economic geography by applying some of its essential theoretical ideas to an emerging political framework.
Growth corridors have been an instrument of
economic development for decades but have gained new
attention in regional economic development policies in recent years, e.g., in Sub-Saharan Africa or Southeast Asia.
They are seen by policy makers and private businesses as
catalysts of regional economic integration, pushing traditional businesses into increasingly complex international
value chains. However, the outcomes of such development
initiatives are still barely understood. Critics argue that development policies are based on simplified models that are
unable to sufficiently address the complexity of regional
development. Policies on value-chain development, for
example, can lead to conflicts, external dependencies,
land rush, and a polarization of wealth. Growth corridors
often go hand-in-hand with socio-economic transformations and land-use conflicts. This paper first discusses the
theoretically possible desired and undesired regional socio-economic effects of modern corridors. Second, we illustrate the potential and challenges to realize integrative
(or inclusive) development by contrasting three growth
corridors: the SAGCOT growth corridor in Tanzania, the
Walvis Bay-Ndola-Lubumbashi Development Corridor
(WBNLDC) in Namibia, Zambia and Zimbabwe, and the
growth corridors in the Greater Mekong Subregion (GMS)
Are old regions less attractive? Interregional labour migration in a context of population ageing
(2021)
Abstract
Regional demographic change is often conceptualized as a circular process, where out‐migration continuously worsens conditions of population ageing and shrinkage. Thus, if migration acts as a consequence as well as cause of ageing, migration patterns should be influenced by the age structure of origin and destination regions. This paper analyses individual‐level migration decisions of full‐time employees across 326 German regions between 1997 and 2013 using binary choice models. The results show that individuals are more likely to migrate out of and less likely to migrate towards ageing regions. Moreover, the identified patterns are consistent with age‐selective migration reinforcing ageing processes and polarization of demographic structure.
Abstract
We investigated four subaerial (paleo)lacustrine landforms at the north‐eastern shoreline of Schweriner See, north‐eastern Germany. These included two beach ridges, one subaerial nearshore bar and a silting up sequence located close to a fossil cliff, which marks the former maximum extent of Schweriner See. We used luminescence profiling with a SUERC portable OSL device (POSL) on all four sediment sequences in combination with sedimentological investigations such as grain size, loss‐on‐ignition and magnetic susceptibility to provide information on the various formations in a lacustrine depositional environment. The POSL reader was used on pre‐treated polymineral samples to gain an insight into luminescence distribution within the individual sediment sequences, but also among the four sequences. POSL proved valuable to understand depositional processes, which were not visible in lithology or sedimentological parameters. With somewhat larger uncertainty this method provides relative chronologies of the sediment sequences. Additionally, we carried out radiocarbon dating and full optical stimulated luminescence (OSL) dating to establish a chronological framework. OSL ages proved to be more reliable to date beach ridges in this setting than radiocarbon samples, which were severely influenced by sediment reworking. This combined approach of sedimentological analyses, luminescence profiling and absolute age determinations revealed details in depositional processes at Schweriner See which otherwise would have remained undetected. Furthermore, it helped to set these subaerial (paleo)lacustrine landforms in a chronological framework.
Body-size variability results from a variety of extrinsic and intrinsic factors (environmental and biological influences) underpinned by phylogeny. In ostracodes it is assumed that body size is predominantly controlled by ecological conditions, but investigations have mostly focused on local or regional study areas. In this study, we investigate the geographical size variability (length, height, and width) of Holocene and Recent valves of the salinity-tolerant ostracode species Cyprideis torosa within a large geographical area (31°–51° latitude, and 12°–96° longitude). It is shown that distant local size clusters of Cyprideis torosa are framed within two large-scale geographical patterns. One pattern describes the separation of two different size classes (i.e., morphotypes) at around ∼42° N. The co-occurrence of both size morphotypes in the same habitats excludes an environmental control on the distribution of the morphotypes but rather could point to the existence of two differentiated lineages. Generally, correlations between valve size and environmental parameters (salinity, geographical positions) strongly depend on the taxonomic resolution. While latitude explains the overall size variability of C. torosa sensu lato (i.e., undifferentiated for morphotypes), salinity-size correlations are restricted to the morphotype scale. Another large-scale pattern represents a continuous increase in valve size of C. torosa with latitude according to the macroecological pattern referred as Bergmann trend. Existing explanations for Bergmann trends insufficiently clarify the size cline of C. torosa which might be because these models are restricted to intraspecific levels. The observed size-latitude relationship of C. torosa may, therefore, result from interspecific divergence (i.e., size ordered spatially may result from interspecific divergence sorting) while environmental influence is of minor importance. Our results imply that geographical body-size patterns of ostracodes are not straightforward and are probably not caused by universal mechanisms. Consideration of phylogenetic relationships of ostracodes is therefore necessary before attempting to identify the role of environmental controls on body size variability.
To reduce global greenhouse gas emissions in order to limit global warming to 1.5°C, individuals and households play a key role. Behavior change interventions to promote pro-environmental behavior in individuals are needed to reduce emissions globally. This systematic literature review aims to assess the a) evidence-based effectiveness of such interventions and b) the content of very successful interventions without limiting the results to specific emitting sectors or countries. Based on the “PICOS” mnemonic and PRISMA statement, a search strategy was developed, and eligibility criteria were defined. Three databases (Embase, PsycInfo, and Web of Science) were searched to retrieve and review potential literature. As a result, 54 publications from 2010 to 2021 were included in the analysis. The results show that most interventions only have small positive effects or none at all. A total of 15 very successful interventions focused on the sectors of mobility, energy, and waste and incorporated improved (infra-) structures, education, feedback, enablement or made the sustainable option the default. Six evidence-based recommendations for content, timing, and setting are deducted and given for interventions on enhancing pro-environmental behavior (PEB). In summary, although the various interventions and intervention types to promote PEB differ in their effectiveness, very successful interventions have common elements. Future research should focus on high-/low-impact and high-/low-cost behavior to develop interventions that aim at high-impact but low-cost behavior changes, or avoid low-impact but high-cost behavior.
Semi-arid Mongolia is a highly sensitive region to climate changes, but the region’s Holocene paleoclimatic evolution and its underlying forcing mechanisms have been the subject of much recent debate. Here we present a continuous 7.4 ka sediment record from the high-altitude Shireet Naiman Nuur (Nuur = lake) in the central Mongolian Khangai Mountains. We extensively dated the sediments and analyzed elemental composition and bulk isotopes for lake sediment characterization. Our results show that 14C-dating of bulk organic carbon and terrestrial macrofossils provide a robust and precise chronology for the past 7.4 ± 0.3 cal ka BP at Shireet Naiman Nuur and 14C-ages are mostly in stratigraphic order. The 14C-based chronology is confirmed by paleomagnetic secular variations, which resemble the predictions of spherical harmonic geomagnetic field models. The very good chronological control makes paleomagnetic secular variation stratigraphy a powerful tool for evaluating and refining regional 14C-chronologies when compared to the record presented here. The lake sediment proxies TOC, N, log (Ca/Ti) and log (Si/Ti) reveal increased lake primary productivity and high growing season temperatures from 7.4 ± 0.3 to 4.3 ± 0.2 cal ka BP, which is likely the result of stronger summer insolation and pronounced warming. Reduced summer insolation thereafter results in decreased productivity and low growing season temperatures at Shireet Naiman Nuur from 4.3 ± 0.3 cal ka BP until present day. The globally acknowledged 4.2 ka event also appears as a pronounced cooling event at Shireet Naiman Nuur, and additional abrupt cooling events occurred during minima in total solar irradiance at ∼3.4, 2.8 and 2.4 ka BP. Low lake primary productivity and growing season temperatures are likely the result of longer ice cover periods at the high-altitude (2,429 m a.s.l.) Shireet Naiman Nuur. This leads to shorter mixing periods of the lake water which is supported by more positive δ13CTOC because of increased incorporation of dissolved HCO3
− by aquatic producers during periods of longer ice cover.
Madagascar houses one of the Earth’s biologically richest, but also one of most endangered, terrestrial ecoregions. Although it is obvious that humans substantially altered the natural ecosystems during the past decades, the timing of arrival of early inhabitants on Madagascar as well as their environmental impact is still intensively debated. This research aims to study the beginning of early human impact on Malagasy natural ecosystems, specifically on Nosy Be island (NW Madagascar) by targeting the sedimentary archive of Lake Amparihibe, an ancient volcanic crater. Based on pollen, fungal spore, other non-pollen palynomorph, charcoal particle and diatom analyses combined with high-resolution sediment-physical and (in)organic geochemical data, paleoenvironmental dynamics during the past three millennia were reconstructed. Results indicate a major environmental change at ca. 1300 cal BP characterized by an abrupt development of grass (C4) dominated and fire disturbed landscape showing the alteration of natural rain forest. Further, increased soil erodibility is suggested by distinct increase in sediment accumulation rates, a strong pulse of nutrient input, higher water turbidity and contemporaneous increase in spores of mycorrhizal fungi. These parameters are interpreted to show a strong early anthropogenic transformation of the landscape from rain forest to open grassland. After ca. 1000 cal BP, fires remain frequent and vegetation is dominated by forest/grassland mosaic. While natural vegetation should be dominated by rain forest on Nosy Be, these last results indicate that human continuously impacted the landscapes surrounding the lake. At a local scale, our data support the “subsistence shift hypothesis” which proposed that population expansion with development of herding/farming altered the natural ecosystems. However, a precise regional synthesis is challenging, since high-resolution multi-proxy records from continuous sedimentary archives as well as records located further north and in the hinterland are still scarce in Madagascar. The lack of such regional synthesis also prevents precise comparison between different regions in Madagascar to detect potential (dis)similarities in climate dynamics, ecosystem responses and anthropogenic influences at the island’s scale during the (late) Holocene.
In this article, we address the climate crisis as a moral issue and discuss the relevant moral and emotional processes and the role of the media underlying the motivations of individuals to behave in a less carbon-emitting manner. We provide theoretical insights from social psychology and emotion research and empirical data based on an online survey from Germany (N = 979). In the theoretical part, we outline the role of emotions in influencing carbon-related behavior, with a particular focus on self-condemning (e.g., guilt or shame), self-praising (e.g., pride), or other-suffering emotions (e.g., empathy). We further summarize the reasons for the low influence of the media on carbon-related behavior compared to the COVID-19 pandemic. The empirical results confirm that participants reported other- suffering and self-condemning emotions in response to news content and rated their likelihood of personal behavior change as high when confronted with news about the climate crisis on a daily basis, as has been widely the case during the COVID-19 pandemic. We argue that the media is responsible for regularly reporting on the victims of the climate crisis in order to generalize self-condemning and other-suffering emotions into affective attitudes. Opinion leaders can function as role models for low-carbon behavior.
Open and analysis-ready data, as well as methodological and technical advancements have resulted in an unprecedented capability for observing the Earth’s land surfaces. Over 10 years ago, Landsat time series analyses were inevitably limited to a few expensive images from carefully selected acquisition dates. Yet, such a static selection may have introduced uncertainties when spatial or inter-annual variability in seasonal vegetation growth were large. As seminal pre-open-data-era papers are still heavily cited, variations of their workflows are still widely used, too. Thus, here we quantitatively assessed the level of agreement between an approach using carefully selected images and a state-of-the-art analysis that uses all available images. We reproduced a representative case study from the year 2003 that for the first time used annual Landsat time series to assess long-term vegetation dynamics in a semi-arid Mediterranean ecosystem in Crete, Greece. We replicated this assessment using all available data paired with a time series method based on land surface phenology metrics. Results differed fundamentally because the volatile timing of statically selected images relative to the phenological cycle introduced systematic uncertainty. We further applied lessons learned to arrive at a more nuanced and information-enriched vegetation dynamics description by decomposing vegetation cover into woody and herbaceous components, followed by a syndrome-based classification of change and trend parameters. This allowed for a more reliable interpretation of vegetation changes and even permitted us to disentangle certain land-use change processes with opposite trajectories in the vegetation components that were not observable when solely analyzing total vegetation cover. The long-term budget of net cover change revealed that vegetation cover of both components has increased at large and that this process was mainly driven by gradual processes. We conclude that study designs based on static image selection strategies should be critically evaluated in the light of current data availability, analytical capabilities, and with regards to the ecosystem under investigation. We recommend using all available data and taking advantage of phenology-based approaches that remove the selection bias and hence reduce uncertainties in results.
The switch from working in-office to working from home in the context of the COVID-19 pandemic had a significant impact on people’s mobility behavior. In view of the need for action arising from the ongoing challenge of climate change, these changes should be seen as an opportunity to reduce emissions in the traffic sector. The aim of this study was to analyze changes in work-related mobility that occurred during the COVID-19 pandemic using the case of a multinational medium-sized retail chain situated in semi-rural Germany. The case study allowed us to examine those changes in connection with individual attitudes and perspectives of the company and its employees. Thus, we quantitatively recorded the mobility behavior of the company’s employees, followed by an expert interview to ascertain the company’s perspective. We found a reduction in the frequency of commuting and business trips made by employees, which seemed to continue beyond the COVID-19 crisis. However, according to our findings these changes were not based on individual motivation to act in a climate-aware manner but are subject to the framework conditions created by employers for the adoption of climate-friendly behavior. The results of this work could be used by companies and policymakers to create such favorable framework conditions.
This thesis aims to investigate effects of anthropogenic environmental impact on the Richards Bay area. Located on the east coast of South Africa, Richards Bay Harbour evolved into the country’s premier bulk cargo port. The Associated change in land-use and industrial as well as agricultural pollution pose environmental, ecological and human health risks. Here, sedimentological and geochemical investigations focus on the port as final sink for environmental and industrial pollutants, such as metal concentrations, organochlorine pesticides and microplastics.
The study is based on investigations of surface sediment samples from the water-sediment interface to identify spatial distribution patterns, as well as sediment cores to follow temporal changes. Endmember modelling of grainsize distributions, proved to be a viable parameter to distinguish different accumulation spaces and enabled the classification into six harbour sub-basins. Subsequent investigations on the content of microplastics, Polyethylene terephthalate (PET) and Low-density polyethylene (LDPE), showed that these different types of microplastics predominate in two different areas: PET appears to be directly tied to higher populated (tourism) beaches, while LDPE is deposited in low-current sub-basins. Increased metal concentrations link to activities at the bulk cargo berths, where especially Cr and Cu concentrations exceeded the local sediment guideline thresholds. In the areas of high metal concentrations, bioindicators (ostracods, foraminiferas, diatoms) also indicate increased shares of malformed specimens. Multiple recovered sediment cores recorded changes in recent export practices, indicating ceased Cu handling and increased Cr handling over the past decade. Noticing multiple possible influencing factors on elemental distributions, created by the surrounding geological and industrial impact, the usefulness of different normalisers (Al, Fe, Rb, Ti and silt fraction) for Cr, Cu, Co and Pb concentrations was compared and site specific baseline metal concentrations were defined. This identified Al and Rb to be effective normalisers in Richards Bay and Fe or Ti to be affected by local conditions. Data of organochlorine pesticide pollution was gathered in the area of Richards Bay, Goedertrouw Dam and Umlalazi River. The two dominant groups of contaminants detected are dichlorodiphenyltrichloroethanes (ΣDDT, 12 – 350 ng g-1), linked to the use of malaria vector control, and hexachlorocyclohexanes (ΣHCH 35 – 230 ng g-1), an agricultural insecticide. Both indicate recent entry and exceed sediment quality guideline limits, raising concern for local communities and estuarine environments. Seismic data was used to investigate the preindustrial evolution of the incised valley system and bayhead delta at Richards Bay Harbour. A stratigraphically supported development model was created. The thesis shows that harbour sediment is an important sink for inorganic and organic contaminants. Each investigation on environmental pollutants, such as metals, pesticides, microplastics or bioindicator analyses, indicates their deposition in distinct harbour sub-basins. Therefore, their effect can be spatially differentiated and related to plausible sources of pollution. Richards Bay thus represents a variously affected system along the South African coast, in which it is necessary to take environmental protection measures in terms of sustainable and environmentally friendly management.
Here, we provide a detailed taxonomic reassessment of a historically collected chondrichthyan dental assemblage from the lower Kimmeridgian of Czarnogłowy in north-western Poland and discuss its significance for better understanding hybodontiform diversity patterns prior to their post-Jurassic decline in fully marine environments. In spite of its low taxonomic diversity, consisting of four large-toothed taxa (viz., Strophodus udulfensis, Asteracanthus ornatissimus, Planohybodus sp. and cf. Meristodonoides sp.), this assemblage is remarkable in that there are only very few Mesozoic hybodontiform assemblages with more large-toothed genera or even species. Comparisons with other European Late Jurassic hybodontiform-bearing localities demonstrate fairly homogenous distribution patterns characterized by large-bodied epipelagic forms of high dispersal ability. This is in stark contrast to post-Jurassic hybodontiform associations, which are dominated by smaller species that were predominantly bound to marginal marine and continental waters, suggesting a major reorganization of chondrichthyan communities during the Early Cretaceous.
Bentonite is currently proposed as a potential backfill material for sealing high-level radioactive waste in underground repositories due to its low hydraulic conductivity, self-sealing ability and high adsorption capability. However, saline pore waters, high temperatures and the influence of microbes may cause mineralogical changes and affect the long-term performance of the bentonite barrier system. In this study, long-term static batch experiments were carried out at 25 °C and 90 °C for one and two years using two different industrial bentonites (SD80 from Greece, B36 from Slovakia) and two types of aqueous solutions, which simulated (a) Opalinus clay pore water with a salinity of 19 g·L−1, and (b) diluted cap rock solution with a salinity of 155 g·L−1. The bentonites were prepared with and without organic substrates to study the microbial community and their potential influence on bentonite mineralogy. Smectite alteration was dominated by metal ion substitutions, changes in layer charge and delamination during water–clay interaction. The degree of smectite alteration and changes in the microbial diversity depended largely on the respective bentonite and the experimental conditions. Thus, the low charged SD80 with 17% tetrahedral charge showed nearly no structural change in either of the aqueous solutions, whereas B36 as a medium charged smectite with 56% tetrahedral charge became more beidellitic with increasing temperature when reacted in the diluted cap rock solution. Based on these experiments, the alteration of the smectite is mainly attributed to the nature of the bentonite, pore water chemistry and temperature. A significant microbial influence on the here analyzed parameters was not observed within the two years of experimentation. However, as the detected genera are known to potentially influence geochemical processes, microbial-driven alteration occurring over longer time periods cannot be ruled out if organic nutrients are available at appropriate concentrations.
: Compacted bentonite is currently being considered as a suitable backfill material for sealing
underground repositories for radioactive waste as part of a multi-barrier concept. Although showing
favorable properties for this purpose (swelling capability, low permeability, and high adsorption
capacity), the best choice of material remains unclear. The goal of this study was to examine and
compare the hydration behavior of a Milos (Greek) Ca-bentonite sample (SD80) in two types of
simulated ground water: (i) Opalinus clay pore water, and (ii) a diluted saline cap rock brine using
a confined volume, flow-through reaction cell adapted for in situ monitoring by X-ray diffraction.
Based on wet-cell X-ray diffractometry (XRD) and calculations with the software CALCMIX of the
smectite d(001) reflection, it was possible to quantify the abundance of water layers (WL) in the
interlayer spaces and the amount of non-interlayer water uptake during hydration using the two
types of solutions. This was done by varying WL distributions to fit the CALCMIX-simulated XRD
model to the observed data. Hydrating SD80 bentonite with Opalinus clay pore water resulted
in the formation of a dominant mixture of 3- and 4-WLs. The preservation of ca. 10% 1-WLs and
the apparent disappearance of 2-WLs in this hydrated sample are attributed to small quantities of
interlayer K (ca. 8% of exchangeable cations). The SD80 bentonite of equivalent packing density
that was hydrated in diluted cap rock brine also contained ca. 15% 1-WLs, associated with a slightly
higher concentration of interlayer K. However, this sample showed notable suppression of WL
thickness with 2- and 3-WLs dominating in the steady-state condition. This effect is to be expected for
the higher salt content of the brine but the observed generation of CO2 gas in this experiment, derived
from enhanced dissolution of calcite, may have contributed to the suppression of WL thickness. Based
on a comparison with all published wet-cell bentonite hydration experiments, the ratio of packing
density to the total layer charge of smectite is suggested as a useful proxy for predicting the relative
amounts of interlayer and non-interlayer water incorporated during hydration. Such information is
important for assessing the subsequent rates of chemical transport through the bentonite barrier.
Influencing Factors for Sustainable Dietary Transformation—A Case Study of German Food Consumption
(2022)
In a case study of Germany, we examine current food consumption along the three pillars of sustainability to evaluate external factors that influence consumers’ dietary decisions. We investigate to what extent diets meet nutritional requirements (social factor), the diets’ environmental impact (ecological factor), and the food prices’ influence on purchasing behavior (economic factor). For this, we compare two dietary recommendations (plant-based, omnivorous) with the status quo, and we examine different consumption styles (conventional, organic produce). Additionally, we evaluate 1446 prices of food items from three store types (organic store, supermarket, and discounter). With this, we are able to evaluate and compare 30 different food baskets along their health, environmental, and economic impact. Results show that purchasing decisions are only slightly influenced by health-related factors. Furthermore, few consumers align their diet with low environmental impact. In contrast, a large share of consumers opt for cheap foods, regardless of health and environmental consequences. We find that price is, arguably, the main factor in food choices from a sustainability standpoint. Action should be taken by policy makers to financially incentivize consumers in favor of healthy and environmentally friendly diets. Otherwise, the status quo further drives especially underprivileged consumers towards unhealthy and environmentally damaging consumption.
Pilot sites are currently used to test the performance of bentonite barriers for sealing high-level radioactive waste repositories, but the degree of mineral stability under enhanced thermal conditions remains a topic of debate. This study focuses on the SKB ABM5 experiment, which ran for 5 years (2012 to 2017) and locally reached a maximum temperature of 250 °C. Five bentonites were investigated using XRD with Rietveld refinement, SEM-EDX and by measuring pH, CEC and EC. Samples extracted from bentonite blocks at 0.1, 1, 4 and 7 cm away from the heating pipe showed various stages of alteration related to the horizontal thermal gradient. Bentonites close to the contact with lower CEC values showed smectite alterations in the form of tetrahedral substitution of Si4+ by Al3+ and some octahedral metal substitutions, probably related to ferric/ferrous iron derived from corrosion of the heater during oxidative boiling, with pyrite dissolution and acidity occurring in some bentonite layers. This alteration was furthermore associated with higher amounts of hematite and minor calcite dissolution. However, as none of the bentonites showed any smectite loss and only displayed stronger alterations at the heater–bentonite contact, the sealants are considered to have remained largely intact.
ABSTRACT
The small terrestrial gastropod Vertigo pseudosubstriata Ložek, 1954 is one of the rarest glacial indicator species in the Pleistocene of Central and Eastern Europe. In all, this species has been found at only about 15 sites in Europe. V. pseudosubstriata was initially described as a fossil in Central Europe and was discovered only later alive in Central Asia. With regard to its modern distribution, 25 habitats with V. pseudosubstriata have been examined in Tien Shan and in the central and southern Altai. These findings seem to capture the contemporary distribution of the species and provide information on the boundaries of its ecological requirements. These data are of great significance for the interpretation of the fossil assemblages. Since the few fossil specimens in Europe date from very different glacial periods in the Elsterian, Saalian Complex and Weichselian, it can be concluded that V. pseudosubstriata apparently immigrated in at least three distinct waves. Most of the Pleistocene specimens in eastern Central Europe and Eastern Europe are reported from archaeological sites of the Upper Middle Weichselian (Gravettian), roughly between 33 and 29 ka cal
bp. In this paper, we review all reported modern and fossil occurrences and discuss the species' ecological range.
According to a basic model, the formation of the coastal barriers in the southwestern Baltic can be divided into four evolutionary stages which are characterized by different rates of sea-level rise and varying relations between sediment supply and accommodation space. This model is tested using the example of a strandplain of the island Usedom, along with a local sea-level curve that reflects even smaller fluctuations of the water table and a detailed chronostratigraphy based on OSL measurements that allows the correlation of the morphodynamics with specific climatic phases. The resulting evolution scheme generally confirms the basic model but the timing of the stages depends on the inherited relief and has to be adjusted locally. A comparison with barriers from the W and SW Baltic region shows that the development during the past 5000 years was controlled by climate fluctuations which caused minor variations of the rather stable sea level and consequential changes in sediment supply, accommodation space and foredune deposition. Progradation decline can mainly be related to cool and windy climate phases which centered around 4.2, 2.8, 1.1, and 0.3 ka b2k, while increasing progradation correlated with warmer climate around 3.5, 2.0, and 0.9 ka b2k. The climate warming and the increasing sea-level rise in the recent past, however, led to shrinking progradation rates and may indicate a critical point beyond which the main progradation trend of the past turns into erosion.
This work scrutinises the policy shift in Germany with the change in leitmotif from biotechnology to bioeconomy and examines the associated implications at various levels. The emergence and implementation of innovation policy funding programmes show that the policy transition did not follow a linear sequence. Neither excessive prioritisation nor neglect of a selected sector can be confirmed in this analysis. However, the policy shift from biotechnology to bioeconomy has not only consequences in terms of its content, but also affects the spatial distribution of R&D funding. Against the background of existing polarisation tendencies and the growing acknowledgement of inclusive innovation policy approaches, this study examines the importance the bioeconomy can assume in the reduction of regional disparities. In ‘organisationally thick’ regions, depending on the involvement of private actors, specialisation and regional branching can be observed. It is found that, for rural regions, the bioeconomy can be an appropriate tool for regional development, since other industries are often not present.
Climate change has strongly affected mountain forests through an increasing intensity and frequency of disturbances and forest dieback in recent decades. However, given the strong relevance of forest dieback and potential impacts on forest stakeholders and local inhabitants, it is surprising that this research field is seldom investigated to date. Therefore, this study deals with the perception of climate change-related consequences as well as possible silvicultural adaptation strategies for the Bavarian Forest. Since it can be assumed that various forest ecosystem services will be increasingly in demand in the future, participation by all stakeholders is essential. Therefore, a sequential, mixed-method approach (qualitative and quantitative survey) allows developing concrete guidelines and strategies for adaptive management, in which the diverse social demands on forests can be adequately taken into account.
Abstract
Interbedded contourites, turbidites and pelagites are commonplace in many deep‐water slope environments. However, the distinction between these different facies remains a source of controversy. This detailed study of calcareous contourites and associated deep‐marine facies from an Eocene–Miocene sedimentary succession on Cyprus clearly documents the diagnostic value of microfacies in this debate. In particular, the variability of archetypical bi‐gradational contourite sequences and their internal subdivision (bedding, layering and lamination) are explored. Contourites can be distinguished from turbidites, pelagites and hemipelagites by means of carbonate microfacies in combination with bed‐scale characteristics. Particle composition provides valuable information on sediment provenance. Depositional texture, determined by the ratio between carbonate mud and bioclasts, is crucial for identifying bi‐gradational sequences in both muddy and sandy contourites, and normally‐graded sequences in turbidite beds. Equally important are the type and preservation of traction structures, as well as the temporality and impact of bioturbation. Shell fragmentation under conditions of increased hydrodynamic agitation (textural inversion) is recognized as a carbonate‐specific feature of bioclastic sandy contourites.
Abstract
Peatlands are lands with a peat layer at the surface, containing a large proportion of organic carbon. Such lands cover ≈1 000 000 km2 in Europe, which is almost 10% of the total surface area. In many countries, peatlands have been artificially drained over centuries, leading to not only enormous emissions of CO2 but also soil subsidence, mobilization of nutrients, higher flood risks, and loss of biodiversity. These problems can largely be solved by stopping drainage and rewetting the land. Wet peatlands do not release CO2, can potentially sequester carbon, help to improve water quality, provide habitat for rare and threatened biodiversity, and can still be used for production of biomass (“paludiculture”). Wisely adjusted land use on peatlands can substantially contribute to low‐emission goals and further benefits for farmers, the economy, society, and the environment.
Multiproxy investigations of lacustrine sediments from Laguna Azul (52 °S) document multi-millennial Holocene influences of Southern Hemispheric Westerlies (SHW) on the hydroclimatic variability of south-eastern Patagonia. During the last 4000 years, this hydroclimatic variability is overprinted by centennial warm/dry periods. A cool/wet period from 11,600 to 10,100 cal. BP is succeeded by an early Holocene dry period (10,100–8300 cal. BP) with a shallow lake, strong anoxia, methanogenesis and high salinity. Between 8300 and 4000 cal. BP the influence of SHW weakened, resulting in a freshwater lake considered to be related to less arid conditions. Since 4000 cal. BP, regional temperature decreased accompanied by re-intensification of SHW reaching full strength since 3000 cal. BP. Centred around 2200, 1000 cal. BP and in the 20th century, Laguna Azul experienced century-long warm/dry spells. Between these dry periods, two pronounced moist periods are suggested to be contemporaneous to the ‘Dark Age Cold Period’ and the ‘Little Ice Age’. Different from millennial SHW variations, centennial fluctuations appear to be synchronous for South America and the Northern Hemisphere. Changes in solar activity, large volcanic eruptions and/or modulations of ocean circulation are potential triggers for this synchronicity.
The achievement and monitoring of a good environmental status on continental shelf seas requires
the use of acoustic remote sensing techniques due to their range. The interpretation of acoustic signals
for the identification of benthic communities, however, is still in its infancy. In this thesis, the results
of two field campaigns conducted in a sandy environment off the shore of Sylt Island (North Sea)
utilizing ship- and lander-based acoustic and optical remote sensing techniques are discussed. The
objective of the thesis is a better knowledge of the impact of the polychaete Lanice conchilega on
physical seafloor properties, especially roughness at a cm to mm scale, which is relevant for
understanding acoustic scatter. The results show a clear impact of L. conchilega on roughness even in
sparse populations of less than 2% coverage. However, these sparsely populated areas could not be
reliably identified with acoustic data; a denser population of L. conchilega provided a clearer signal for
the acoustic remote sensing methods. The results are promising regarding the broader use of acoustic
remote sensing techniques for environmental monitoring in selected habitats, although the
determination of minimum population thresholds that can be identified will require further studies.
A hydroxy-sodalite/cancrinite zeolite composite was synthesized from low-grade calcite-bearing kaolin by hydrothermal alkali-activation method at 160 C for 6 h. The effect of calcite addition on the formation of the hydroxy-sodalite/cancrinite composite was investigated
using artificial mixtures. The chemical composition and crystal morphology of the synthesized zeolite composite were characterized by X-ray powder diffraction, infrared spectroscopy, scanning electron microscopy, and N2 adsorption/desorption analyses. The average specific surface area is around 17–20 m2g-1, whereas the average pore size lies in the mesoporous range (19–21 nm). The synthesized zeolite composite was used as an adsorbent for the removal of heavy metals in aqueous solutions. Batch experiments were employed to study the influence of adsorbent dosage on heavy metal removal eciency. Results demonstrate the effective removal of significant quantities of Cu, Pb, Ni, and Zn from aqueous media. A comparative study of synthesized hydroxy-sodalite and
hydroxy-sodalite/cancrinite composites revealed the latter was 16–24% more effcient at removing heavy metals from water. The order of metal uptake effciency for these zeolites was determined to be Pb > Cu > Zn > Ni. These results indicate that zeolite composites synthesized from natural calcite-bearing kaolin materials could represent effective and low-cost adsorbents for heavy metal removal using water treatment devices in regions of water hortage.
The Müritzeum is a nature discovery centre and a museum in the heart of the Mecklenburg Lake District. It is the first natural history museum in Mecklenburg-Vorpommern, with natural history collections that are over 150 years old, and are still growing today. The collections contain about 290 000 specimens from the fields of botany, zoology and geology. An extensive library and an archive are also
part of the museum. Collecting, preserving and researching natural history are our main spheres of activity. The exhibition in the Müritzeum offers the visitor a comprehensive insight into the development of the nature and landscape of northeastern Germany and of Mecklenburg-Vorpommern and the Lake Müritz region in particular. The largest aquarium for indigenous freshwater species in Germany enables visitors to imagine themselves in the underwater world of the Mecklenburg Lake District.
Archaeological discoveries in the Tollense Valley represent remains of a Bronze Age battle of ca.1300–1250 BCE, documenting a violent group conflict hitherto unimagined for this period of time in Europe, changing the perception of the Bronze Age. Geoscientific, geoarchaeological and palaeobotanical investigations have reconstructed a tree- and shrubless mire characterised by sedges, reed and semiaquatic conditions with a shallow but wide river Tollense for the Bronze Age. The exact river
course cannot be reconstructed, but the distribution of fluvial deposits traces only a narrow corridor, in which the Tollense meandered close to the current riverbed. The initial formation of the valley mire dates to the transition from the Weichselian Late Glacial to the early Holocene.
The site at the southern shore of Krakower See shows the Quaternary geology of the surrounding
area. The local Quaternary sequence comprises a thickness of 50–100m of Quaternary deposits while
the surface morphology is dominated by the ice marginal position of the Pomeranian moraine, which
passes through the area. The bathymetry of the lake basin of Krakower See indicates a predominant
genesis by glaciofluvial erosion in combination with glacial exaration. Past research in this area has focussed
on the reconstruction of Pleniglacial to Holocene environmental changes, including lake-level
fluctuations, aeolian dynamics, and pedological processes and their modification by anthropogenic
land use.
Monitoring of Calcite Precipitation in Hardwater Lakes with Multi-Spectral Remote Sensing Archives
(2017)
The importance of investments by emerging country multinationals to industrialised economies has risen continuously as illustrated by the growing number of Chinese merger and acquisitions (M&A) of German Mittelstand firms. This dissertation aims to analyse the effects of institutional distances on the M&A process. To this end, William Scott’s concept of institutions is newly operationalized to investigate institutional distances on the intra-firm, regional and international level. Through interviews with involved firms, intermediaries and key persons with dual backgrounds, the effects on different dimensions of the subsidiaries’ embeddedness as well as various mechanisms of institutional work during and after the M&A are evaluated.
The southern Baltic Sea embodies an incomparable geological archive of the tectonic evolution of the 450 Ma old Trans‐European Suture Zone (TESZ). This WNW to NW trending suture formed during the collision of Baltica and Avalonia and has accommodated the repeatedly changing stress regimes since then, as evidenced by numerous fault zones and systems. The German offshore part in the vicinity of Rügen Island is strongly block‐faulted, with each block showing a specific geological pattern, enabling the reconstruction of the structural evolution of the area.
The work of this thesis is part of the USO working group of the University of Greifswald and the Geological Survey of Mecklenburg‐Western Pomerania, which aims to build a unified three‐dimensional tectonic model of the southern Baltic Sea area. This thesis presents the results of new structural investigations of the Arkona, Wolin and Gryfice blocks north and east of Rügen. Especially, conflicting structural analyses in the previous work are united into a consistent model.
The integrated interpretation of 144 reprocessed seismic vintage lines (original Petrobaltic data) and 23 high resolution academic seismic sections (from the Universities of Hamburg and Bremen), with additional consideration of on‐ and offshore wells, revealed 19 seismostratigraphic horizons that subdivide the succession between the Proterozoic basement and the Upper Cretaceous. Up to 100 faults of superior fault zones and systems control the tectonic situation. Besides NW trending deep faults formed during the Palaeozoic, for instance the Wiek and Nord Jasmund faults, and NNW trending Mesozoic faults and flexures that belong to the Western Pomeranian Fault System, other major faults such as the Adler‐Kamień Fault Zone document the polyphase evolution of this area.
The restoration of selected seismic sections support the evaluation of separately generated faults and their reactivation, leading to a subdivision of the tectonic evolution of the area into six stages:
(1) The Caledonian Orogeny (Ordovician/Silurian) was accompanied by a NE‐SW compression, resulting in the formation of the TESZ and an accretionary wedge within the upper crust. (2) The following S to SW trending extension of the Variscan Foreland (Devonian/Carboniferous) triggered the
evolution of the Middle Devonian Old Red Rügen Basin south of the Wiek Fault. Further WNW to NW trending faults (e.g. Nord Jasmund Fault) subdivided the basin. (3) The advancing Variscan Orogeny (Late Carboniferous) caused an increasing NE‐SW orientated compression and subsequently reactivated faults and tilted blocks (e.g. Lohme Sub‐block). (4) The North German Basin and Mid Polish Trough formed by thermic subsidence in the S to SE of the research area during the Permo‐Carboniferous. Simultaneously, the evolution of the Gryfice Graben as part of the Teisseyre‐Tornquist Zone commenced. (5) Due to the Arctic‐North Atlantic Rifting an E‐W trending extension increased. Consequently, grabens such as the Gryfice Graben continued their subsidence. As the stress system rotated counter‐clockwise, the shear strength increased along the NE trending faults. The Western Pomeranian Fault System developed due to intense transtension during the Keuper and Jurassic, and is characterised by pull‐apart structures. (6) In the Upper Cretaceous, a NE‐SW compression, forced by the Africa‐Iberia‐Europe convergence, triggered the reactivation of faults and flexures as reverse ones, the inversion of grabens (e.g. Gryfice Graben), and the formation of anticlines, for instance at the Wolin Block.
This thesis combines the calculation of gridded time structure maps and a detailed fault pattern analysis, and represents the base for a velocity‐ and subsequently depth‐based 3D modelling.
Glacitectonic deformation in the Quaternary caused the tectonic framework of large-scale folds and displaced thrust sheets of Maastrichtian (Upper Cretaceous) chalk and Pleistocene glacial deposits in the southwestern Baltic Sea area.
A wide spectrum of methods has been compiled to unravel the structural evolution of the Jasmund Glacitectonic Complex. The analyses of digital elevation models (DEM) suggest a division into two structural sub-complexes – a northern part with morphological ridges striking NW–SE and a southern part with SW–NE trending ridges. Geological cross sections from the eastern coast (southern sub-complex) were constructed and restored using the software Move™ and the complementary module 2D Kinematic Modelling™.
The final geometric model of the southern sub-complex shows a small-scale fold-and-thrust belt. It includes three different orders of architectural surfaces (see PEDERSEN, 2014): erosional surfaces and the décollement (1st order), thrust faults (2nd order), and beds outlining hanging-wall anticlines as well as footwall synclines (3rd order). Thrust faults of the southern structural sub-complex are mainly inclined towards south, which indicates a local glacier push from the S/SE.
The glacitectonic structures have a surface expression in form of sub-parallel ridges and elongated valleys in between. Geomorphological mapping and detailed landform analyses together with the structural investigations provide an insight into the chronology of sub-complexes formation. The northern part of the glacitectonic complex is suggested to have been formed before the southern one, considering the partly truncated northerly ridges and their superimposition by the southern sub-complex.
Although there is a high number of scientific publications on the glacitectonic evolution of Jasmund, these presented models often lack a consistent theory for the development integrating all parts of the 100 km2 large complex. Therefore, the combination of all results leads to a more self-consistent genetic model for the entire Jasmund Glacitectonic Complex.
Coastal and marginal seas – like the Baltic Sea – serve as natural reaction sites for the turnover and accumulation of land-derived inputs. The main location for the modification and deposition of the introduced material is, in most cases, not the water mass, but the sediment. Its key function as central reactor in the interaction between land and sea has so far been insufficiently studied and assessed. This study was part of the interdisciplinary SECOS project that aimed to identify and evaluate the service functions of sediments in German coastal seas in the context of human use with a focus on the Baltic Sea. One of its goals was to assess sediment functions related to the intermediate storage or final sink of imported material like nutrients and contaminants, and quantify their inventory as well as their mass accumulation rates on multi-decadal to multi-centennial time scales. For that, a detailed examination of the natural and anthropogenic processes that interfere with sediment accumulation in the south-western Baltic Sea basins is essential.
Certain basal Teleostei from the Early Jurassic of Mecklenburg-Western Pomerania (Germany) and the Late Jurassic of the Franconian Alb (Bavaria, Germany), the Swabian Alb (Baden-Württemberg, Germany) and the western Jura-Mountains (Ain, France) are described. The present doctoral dissertation includes four studies, dealing with representatives of “Pholidophoriformes”, Leptolepidae and Orthogonikleithridae. These studies include anatomical descriptions of new taxa and reviews of poorly known fishes. Furthermore, the stratigraphic and palaeobiogeographical distributions of the examined taxa are discussed.
Quang Xuong is considered as one of the most developed districts in Thanh Hoa Province in terms of agricultural. The major purpose of this research is to find good places to suggest for annual crops production in the case study. Therefore, the assessment of land potential productivity, land suitability, and land cover/land use change in different periods is essential for making strategies of sustainable agricultural development as this will help land-users and land managers to discover the potential and limitations of the current existing land conditions to make appropriate policies and plans for future land use. Its results will provide basic information to make reasonable decisions for investments and rational reclamations of cultivated land before and after each crop season in order to meet the objectives of sustainable development in terms of economic efficiency, social acceptability, and environmental protection. The research site is located at latitudes 19 degree 34 minute N - 19 degree 47 minuteN and at longitudes 105 degree 46 minute E - 105 degree 53 minute E. The total area is about 227km2; in which 128km2 is in use for agricultural activities. Based on soil classification methods by FAO-UNESCO (1988), the agricultural land is classified into six main soil groups, including Arenosols, Salic Fluvisols, Fluvisols, Gleysols, Acrisols, and Leptosols, 12 soil units and 18 sub-units. The largest area belongs to the Fluvisols group with 9358.29ha and the smallest area is identified as the Leptosol group with 219.33ha. Most of the soil in this district has low to moderate nutrition, but in general, they are still suitable for agricultural production. There are 42 land units defined in the land mapping, which can be different from each other by one or more land characteristics. The land mapping unit is created from the overlay of all thematic maps of soil chemicals, soil physical characteristics, and relative topography together by application of GIS techniques. It presents land characteristics and properties in this case study and will be used in comparasion with a particular crop requirement for growth in land suitability evaluation process. A certain land unit may be suitable for one or more types of different land use. It is also classified as highly suitable for a specific land utilization type, but less suitable or unsuitable for other crops. For example, in this study, land unit 26 is determined as highly suitable (S1) for growing paddy rice and maize, but it falls into moderately suitability (S2) for groundnut crop by using parametric (square root) method used in this thesis. Depending on the kind of crops need to be evaluated and its requirement for development compared with each land unit characteristics, land-users will determine the best suitable place for crop production. Identification of land use change in different periods of time has become a central key to monitoring of land resources. It is relatively important for effective land management to protect the land resources, especially the land used for agricultural production from overuse and environmental changes. The sprawl of inhabitant areas, development of rural infrastructures, and industrialization are responsible for serious losses of agricultural land. In this study, remote sensing techniques were applied to studying the trends of land cover change in the abovementioned district in a period of about 24 years from 1989 to 2013. ArcGIS software was adopted to develop the land cover and the change of land use maps from 1989 to 2013. Two satellite images with moderate resolution were collected from USGS Earth Explorer website, Landsat5 TM for 1989 and Landsat8 OLI & TIRS for 2013. After image geo-processing, the images were classified into six land cover categories by applying supervised classification method (Maximum Likelihood). The six main obtained land cover types were built-up areas, agricultural land, forest land, water surface area, salty land, and unused land. The overall accuracies of land cover maps for 1989 and 2013 were 94.08% and 92.91%, respectively. The results of change detection analysis indicate that the cultivated, water surface and unused lands decreased by 22%, 17%, and 91%, respectively. In other side, the built-up and salty land increased by 78%, 58%, respectively and forest land increased from 52.69ha in 1989 to 395.76ha in 2013. The assessment of land potential productivity for agricultural production and land suitability for selected annual crops was based on FAO guidelines for land evaluation (FAO, 1976, 1985, and 1993) which were adopted and slightly modified for compatibility with Vietnamese conditions. All related data were stored, analyzed, mapped and presented in ArcGIS software. Weighted Linear Combination Method developed by Hopkins (1977) and GIS techniques were used to analyze and determine the land potential for agricultural use in the study area. The results show that 5.26%, 83.10%, 10.06%, and 1.57% of the investigated areas were assessed as high potential, moderate potential, low potential and very low potential for growing crops. Regarding land suitability evaluation, the simple limitation, parametric (square root), and AHP methods were used to evaluate the suitability levels for selected crops, including paddy rice, sweet potato, groundnut, maize, potato, sesame, soybean, and green pepper. The obtained results indicate that each applied method provides different results of land suitability level for a specific crop in certain land units compared to the other two methods, and OM, soil pH, soil texture, and relative topography were found out as the main limitation factors which affected land suitability level. The study also suggests that three different methods as abovementioned can be expanded and applied in other places with the appropriate factors used for land suitability evaluation according to particular area conditions.
A large portion of the earth's surface is covered with various vegetation classes (i.e. grassland, wetland and agricultural area, forest) of many diverse species and canopy configurations. The ability to assess and to monitor canopy parameters, such as biomass, leaf area index, and vegetation water content, is of vital importance to the study of different agronomic processes. Remote sensing techniques provide a unique capability towards probing different vegetation types and canopy by operating at different bands, observation angle etc. Over the past decades, significant progress has been made in remote sensing techniques of land processes specially vegetation characteristics through development of advanced ground-based, airborne and space-borne microwave sensors, methods and approaches such as theoretical, semi-empirical and empirical models, needed for analyzing the data. These activities have sharply increased in recent years since the launch of different active and passive satellites and sensors. Remote Sensing (RS) science and techniques combined with ground truth data can provide new tools for advanced agricultural crop applications. It has been demonstrated that RS has the ability to estimate biophysical parameters of agricultural crops over time at local, regional, and global scales. In this study, RS images in visible/near infrared (VIS/NIR) domain as well as microwave domain combined with ground truth data were used to assess biophysical parameters of agricultural crop during their whole growing season at Durable Environmental Multidisciplinary Monitoring Information Network (DEMMIN) test site in North East Germany. Ground truth studies were carried out for 31 weeks during 17th April – 13th November 2013 over three crop lands including winter wheat, barley and canola. Landsat 8 OLI, Landsat 7 ETM+ were used for the VIS/NIR studies and TerraSAR-X synthetic aperture radar (SAR) images were used to study biophysical parameters of agricultural crops in microwave part of electromagnetic spectrum. The analysis was conducted by calculating different vegetation indices (VIs) to estimate the biomass (fresh and dry), LAI, and vegetation water content (VWC) of three crops using Landsat 8 OLI and Landsat 7 ETM+ combined with ground truth data. A new concept of Soil Line retrieval from Landsat 8 image was also developed to estimate plant biophysical parameters using soil line related vegetation indices in optical domain of electromagnetic spectrum. Different approaches including univariate, multivariate stepwise regression and semi-empirical water cloud model was also used to estimate the biophysical parameters of agricultural crop using TerraSAR-X data in microwave domain of electromagnetic spectrum. Perhaps the most important conclusion of this study is that the RS approach can provide useful information about estimating agricultural crop parameters over time and local scale, which can therefore provide valuable information to aid the agronomy community.
Tourism is a multifaceted economy and based on existing nature, as well as on culture in a geographical space to become a successful destination for tourism. The topic of this survey is how tourism in the transitioning country of Vietnam influences culture and nature or vice versa. A special focus will be on the transitioning aspect. This study gives insights about how in the transitioning country of Vietnam, tourism can act as an additional driver of change in terms of nature and culture or if tourism is only adapting to these changes. Therefore in the beginning the subject of ‘social-ecological transformation’ is described and furthermore the situation in Vietnam will be introduced. The key aspects here will be within the range of geography and sociology. It becomes evident, that scientific views on this topic are rather diverse, but nevertheless many theoretical aspects can be observed also in the investigation area Vietnam. Within the country several aspects of economic transition already became reality, while others, like social, ecological or political reforms, are still at the beginning. The empirical part of this study deals with existing thoughts, according to the topic of transition, in relation to tourism development and respectively to environmental understanding, by analyzing and comparing positions of 21 international and Vietnamese experts, 569 international tourists and 710 Vietnamese students. By doing so, similarities within opinions about tourism development and the environmental situation in the country became observable. While tourism is rated as a mostly positive development, the current environmental situation has mostly been criticized by all survey participants. Apart from that, connections between both aspects (tourism economy and nature) are often of no importance or the relationship is identified to be just a rudimentary one. In case of these opinions, involvement within one social group and personal experience is of larger importance than cultural conditioning (European or Asian), e.g. own travels, own jobs and own education. This fact becomes visible by very similar ratings of environmental problems on the one hand and the beauty of natural landscapes on the other hand, done by both survey groups; namely international tourists and Vietnamese students.
This thesis aims to develop a palaeogeographic and chronostratigraphic model of the southwestern Baltic Sea area, to improve our understanding of the depositional history of the Late Pleistocene on both a local and a transregional scale. New sedimentological, palaeontological and numerical age data will be presented from three reference sites located at the coast of NE Germany. So far, the chronostratigraphic assignment of Saalian and Weichselian sediments of NE Germany has been based mainly on lithostratigraphic methods and on sparse numerical age data, resulting in a fragmentary age database. Modern sedimentological approaches, such as facies analyses, have been applied only at a few isolated profiles. Thus, a reliable reconstruction of the depositional environments and their stratigraphic positions is still missing for the study area, which makes the correlation between Pleistocene successions from NE Germany and other circum-Baltic regions problematic. To address these lithostratigraphic and geochronologic issues, three crucial profiles were re-investigated using a multiproxy approach, including sedimentological, geochronological, and palaeontological techniques. The Glowe and Kluckow sites are located on the peninsula of Jasmund (Rügen Island), whereas the Klein Klütz Höved (KKH) section is situated between Wismar and Travemünde at the coast of the Mecklenburg Bay. The age-constraining of critical horizons was conducted by luminescence dating of feldspar and quartz grain minerals. Together, these successions represent the Late Saalian to Late Weichselian period and give rise to the following picture. The Glowe and Kluckow sections reveal that ice-free conditions dominated the study site between 47 and 42 ka. Deposition occurred in a steppe-like environment with moderate summers and cool winters. Meandering and braided river systems inhabited by various freshwater species, such as Anodonta cygnea, Pisidium amnicum and Perca fluviatilis, shaped the landscape. A subsequent cooling phase resulted in the establishment of a periglacial landscape and the formation of ice-wedges. This phase is shown in this thesis to be connected to the Klintholm advance documented at 34±4 ka in Denmark. Furthermore, the data indicate the formation of a lacustrine basin during the transition of MIS 3 to MIS 2 under sub-arctic climate conditions. A potential link to the Kattegat ice advance (29 – 26 ka) will be proposed. At 23±2 ka, the study area was characterised by proglacial and ice-contact lakes related to the Last Glacial Maximum ice advance of the Scandinavian Ice Sheet (SIS). This is the first documented SIS advance of Weichselian age, which reached Jasmund at 22±2 ka. The KKH sedimentary succession comprises deposits of Late Saalian to Late Weichselian age: after a period of deglaciation between ~139-134 ka (Termination II; MIS 6), which is preserved in a glaciofluvial sequence deposited in a braided river system, a lacustrine environment was established in an arctic to subarctic climate. During this time, the landscape was vegetated by typical Late Saalian flora communities. The Eemian interglacial is represented by lacustrine to brackish deposits covering the reference pollen zones 1 to 3. During this initial part of the Eemian, thermophile forest elements spread (Quercus, Ulmus), indicating a deciduous forest. The presence of brackish ostracods represents the influence of a marine transgression between 300 and 750 years after the beginning of the Eemian period. A hiatus of more than 90,000 years separates the Eemian from the overlying Late Weichselian sediments. During the Late Weichselian period, the deposition at KKH was dominated by glaciolacustrine and subglacial facies, where the first Weichselian ice advance occurred at 20±2 ka. The sedimentological and geochronological findings in this thesis provide valuable information for the reconstruction of the palaeoenvironmental history from the Late Saalian to Late Weichselian period. The Late Saalian palaeoenvironmental setting is reconstructed, including Termination II and the initial phase of the Eemian interglacial. Furthermore, the Eemian marine transgression is shown to have occurred 300 to 750 years after the beginning of this interglacial. The first proven Weichselian advance of the SIS approached NE Germany between ~23 and ~20 ka. In contrast, there is no evidence to support a pre-LGM advance of Weichselian age to the study area, as proposed by several authors, neither at Glowe and Kluckow, nor at the KKH site. Based on the presented results, and contra what was previously assumed, the MIS 3 Ristinge and Klintholm advance of the SIS, documented in Denmark, did not reach NE Germany.
The present doctoral dissertation comprises new studies on the fossil vertebrate assemblage recovered from the late Early Jurassic marine “Green Series” clay deposits of Grimmen and Dobbertin in north-eastern Germany that contribute to fill the gap of knowledge regarding its faunal composition and its relevance for understanding Early Jurassic vertebrate life. The investigations led to the recognition of wide range of vertebrate taxa, including basal gravisaurian sauropods, secondarily marine reptiles, a diverse fauna of leptolepid fishes, and a new genus and species of pycnodontiform fishes. In addition, a taxonomic revision of the Early Jurassic saurichthyid fish Saurorhynchus was performed, leading to the identification of two new, previously unnamed species. The results provide new insights into the taxonomic, systematic, and ecological diversity of Early Jurassic vertebrates, and hence add significant new data to our knowledge on Lower Jurassic vertebrate palaeobiodiversity patterns.
The focus of this study is on the geochronological and paleo-climatic characterization of late Pleistocene glaciations in Turgen and the Khangai Mountains located in central and western Mongolia. These two mountain ranges form a 700 km long NW-SE transect through Mongolia and allow assumptions of the temporal and causal dynamics of the regional late Quaternary glaciations and their correlation to other mountain glacier records from Central and High Asia. In order to evaluate extent and timing of the Pleistocene glaciations in Mongolia, geomorphological mapping and cosmogenic radionuclide (CRN) surface exposure dating (10Be) were carried out in four valley systems located in the Khangai and Turgen Mountains. Additionally, a coupled 2-D surface energy balance and ice flow model was used to determine steady-state conditions for glaciers under various climatic scenarios. With this model it is possible to test combinations of temperature and precipitation settings, which would produce glacier configurations that fit the field-mapped ice extent. In total, 47 glacial boulders and roche moutonnées were sampled, prepared and AMS measured to determine the absolute timing of moraine formation and ice retreat based on 10Be surface exposure dating. Of these, 27 samples were obtained from the Khangai Mountains (three separate moraine sequences) and 20 samples were taken from the Turgen Mountains (two moraine sequences). The dating results (presented as minimum ages) give evidence for a late Pleistocene maximum ice expansion during late MIS 5 (81−78 ka) and major ice advances during MIS 2 (26−20 ka) in both mountain ranges. Only in the Khangai Mountains (central Mongolia) very significant glacier advances also occurred during mid-MIS 3 (49−35 ka), which exceeded the ice limits set during the MIS 2 glaciation. A final ice position, constructed shortly before the onset of full ice retreat was formed between 19-16 ka, and is likely to represent a recessional ice stillstand, or alternatively a final ice readvance during the early part of the last-glacial-interglacial-transition (LGIT) in both mountain ranges. Energy/mass balance and ice flow modeling results suggest that climatic conditions during the MIS 5 and MIS 3 maximum advances in the Khangai Mountains were depressed between a ∆T of -6.0 to -5.2 °C with a precipitation factor of 1.25-1.75 (P = 125-175 %, compared to modern conditions), and a ∆T of -5.3 to -4.4 °C (P = 75-125 %), respectively. For the MIS 2 ice advances modeling results from the Turgen and Khangai Mountains suggest a temperature depression ∆T of -5.7 to -4.6 °C (at 22 ka; P = 25-50 %) in the East-Turgen, and a ∆T of -7.5 to -6.6 °C (at 20 ka; P = 25-50 %) in the Chulut area (Khangai Mountains). These results document a 1.8 - 2 °C difference of the modeled temperatures required to expand the studied paleo-glaciers in the Turgen and Khangai mountains to their field-mapped MIS 2 ice limits, highlighting a spatially differentiated pattern of paleo-temperature lowering across the studied 700 km NW-SE transect. Taken together, the presented record indicates that the largest ice advance in both investigated mountain ranges occurred during the MIS 5 / MIS 4 transition, despite earlier suggestions by previous studies that the local glacial maximum would be associated with the coldest periods of the last glacial cycle (i.e. MIS 4 or MIS 2). Glacier systems in the Khangai Mountains also increased substantially during MIS 3 (local LGM) in response to cool but comparable wet conditions, probably with a greater-than-today input from winter precipitation and an additional input of recycled moisture from expanded paleo-lakes in the Valley of the Great Lakes. The lack of a severe cooling during the MIS 3 ice advances, and probably also during the late MIS 5 ice expansion, suggests that variations in atmospheric circulation patterns, with its significance for controlling the regional precipitation/moisture supply, was a key driver for these late Pleistocene ice advances in Mongolia. This notwithstanding, there is also clear evidence for the development of an extensive glaciation during MIS 2, coinciding with a period of severe cooling and hyperarid conditions. This highlights that glacier systems in Mongolia responded sensitively, both, to variations in moisture supply and its seasonal distribution, and to the marked insolation minima during the last glacial cycle.
The establishment and management of protected areas has become a universally accepted way to conserve biodiversity and the wide range of goods and services they offer. Sustainable management of forest resources requires good decision-making from a range of different stakeholders. This dissertation develops a model based on spatial data and expert judgments to assess the vulnerability of the most threatened species of fauna and flora in a selected protected area. Based on the study objectives, the availability of data and technology, the study concludes vulnerability as composed of multidimensional losses, which can be measured as a function of the three components: exposure, sensitivity and adaptive capacity. In order to measure vulnerability, the research applies the Analytic Hierarchy Process (AHP), a well-known multi-criteria decision making approach, using the open access Super Decisions software in a spatial database context with the help of Geographic Information Systems (GIS).
Although the Pleistocene deposits exposed in the steep coastal cliffs of Mecklenburg-Vorpommern have been studied for more than a century, the depositional conditions of many lithostratigraphic units remain unclear. There is, in particular, a question whether the individual tills (locally more than 9 successive till units) are mainly subglacial deposits or resedimented (mass flows) in origin (at least in part). The Pleistocene deposits preserve information concerning the former glacial depositional processes. Detailed micromorphological analysis of these deposits can provide key information regarding these processes and thereby aid in the reconstruction of former glacial environments. The island of Rügen is located on the southwestern Baltic Sea coast and was situated in the marginal zone of the Scandinavian Ice Sheet during the last glacial period (Weichselian). Therefore, the region is considered as an ideal area for reconstructing the complex fluctuations in the position of the margin of this ice sheet as it expanded across the Baltic Sea and into northern Germany. Successive glacial advances and retreats of the ice sheet can be reconstructed by specific glacial sedimentation processes and flow-direction criteria derived from a variety of glacial deposits. The investigation area is located near Sassnitz on Rügen, where an imbricated and folded Weichselian succession disconformably overlies Maastrichtian chalk bedrock. The individual till units were sampled for micromorphological analyses to identify the former depositional conditions. Detailed description of the sedimentology and variation in facies, the description of macroscale deformation structures provides the context for the detailed micromorphology study. The three dimensional analysis of the microfabrics is based on the microstructural mapping methodology which enables the identification and interpretation of polyphase deformation within subglacial sediments.
Destination Image, Tourist Satisfaction and Destination Loyalty: A Case Study of Hue, Vietnam
(2016)
Several studies have confirmed the interrelationship among destination image, tourist satisfaction and destination loyalty, in which destination image and tourist satisfaction are believed to have great influences on the destination loyalty of tourists. Located in the central region of Vietnam, Hue holds great potential for tourism development and this destination has also obtained numerous significant tourism achievements over recent years.Nevertheless, there are still a lot of issues needed to be addressed by the destination managers in order to make Hue gain a better position and higher level of destination loyalty in the tourism market, in which successfully communicating an attractive destination image to the tourists and improving their satisfaction are the most important tasks. In fact, there exist very few researches concerning destination image, tourist satisfaction or even destination loyalty which have been done in Hue. Moreover, most of these studies are in very small scale and they only examine either the destination image or the tourist satisfaction or the destination loyalty independently. This paper, therefore, aims to deliver the first and comprehensive theoretical and empirical analysis of destination image, tourist satisfaction and destination loyalty as well as the causal relationship among them in the context of Hue. In this study, a destination loyalty research model was proposed and hypotheses were derived. The empirical data base on two tourist surveys with a total number of 2042 questionnaires collected in Hue in 2013 and 2014. In addition, ten experts were interviewed in different periods during the study. The results find that the tourists’ perceptions on the destination image of Hue are quite positive and the positive level is higher for those who completely have no earlier experience in Hue. It is also discovered that the destination is offering tourists with a pretty satisfactory experience, not as high as their initial expectations, but acceptable with positive ratings received from the tourists. However, if the destination is able to better communicate a positive image to tourists and improves the quality of its offers and services, the tourists’ satisfaction will be increased and thus the destination loyalty will also be enhanced. This finding supports the proposed destination loyalty model: (1) destination image directly influences attribute-satisfaction; (2) destination image and attribute-satisfaction are both direct influences of overall-satisfaction; and (3) overall-satisfaction in turn has a direct and positive impact on destination loyalty. The findings also confirm that attribute-satisfaction and destination image are also the direct influences of destination loyalty. Furthermore, the results add to the proposed loyalty model a new relationship: Destination image is influenced strongly by tourist overall-satisfaction and attribute-satisfaction. The outcomes of this research are expected to be used as a valuable reference for the local policy-makers, governmental agencies, tourism companies and other relevant stakeholders. Also, important theoretical and managerial implications are drawn based on the study findings and the recommendations for future researchers are made from the limitations and scopes of the study.
Geopolymers (GPs) are inorganic binders created by adding alkaline solution (e.g. KOH) to silicates such as furnace slag, fly ash or clay to dissolve Si and Al that polymerises and precipitates to form an inorganic binder material while hardening. GP properties are similar to ordinary Portland cement regarding their high compressive strength or low shrinkage but they are particularly notable for a high resistance to acid and fire. However, the most significant advantage of GP cements is their low CO2 footprint. The most common clay used as GP raw material is kaolin. The aim of this study is to investigate the suitability of illitic clays as a cheaper alternative to kaolin and determine the necessary preparation steps required to produce effective GP binder materials. Three clays dominated by dioctahedral 2:1 layer silicates, in particular interstratifications of mica and smectite were investigated: (1) Illitic clay from Friedland, Northern Germany, containing an irregularly stacked illite-smectite interstratification (R0 I-S), (2) rectorite from Arkansas, USA, as a regular interstratification of mica and smectite, and (3) clay stated as “sárospatakite” from Füzérradvány clay deposit, Northern Hungary, containing a long range ordered I-S (R3). The three types of I-S interstratification-rich clays were extensively characterised and the Friedland clay, as the most probable raw material for GP production, was studied in more detail including several size fraction analyses. These results are used to investigate and determine the parameters necessary to produce suitable precursors for GP binders. Different approaches of clay activation to yield a highly reactive material by milling and heating were examined. Milling was found to be suitable as a preparation step after heating breaking up sintering aggregates to create pathways for the alkaline solution, but not as a substitute for heating. Important parameters for the precursor design such as temperature, time, and heating rate are determined and discussed. Geopolymerisation is considered to be a multi-parameter system and is influenced strongly by the degree of dehydroxylation, Si:Al ratio, or amount of 5-fold coordinated Al. However, in contrast to kaolin-based systems, none of these parameters explain why the illitic Friedland clay heated to 875 °C was found to be most suitable for GP binders. Based on leaching experiments and specific surface area (AS) measurements of the heated Friedland clay, a conceptual model is presented to explain the observed relationship between the heating temperature and the subsequent compressive strength of the GP cement. An optimum between the counteracting reactions of decreasing AS (fewer particles must be covered with GP phase) and decreasing Si+Al dissolved (less GP phase created) is necessary, which exists at 875 °C for the Friedland clay. In this state enough GP phase is created to bind all remaining sintering aggregates to form a cement with high compressive strength. This relationship can be expressed as (Si+Al) / AS (sum of dissolved Si and Al divided by the surface area of grains that must be covered with GP phase), and can be used as a predictive tool for determining the optimal heating temperature. The results presented in this thesis indicate that illitic clays are suitable raw materials as GP binders if the necessary preparation steps of dehydroxylation, sintering and grinding are made. Proxies used to evaluate the optimal conditions for making GP binders are determined including the (Si+Al) / AS ratio as a key relationship that controls the cementation process and determines its ultimate hardness.
Using geopolymers can reduce significant amounts of CO2-emissions during the production compared to Portland cement. Although illite/smectite clays are very abundant on earths crust and rich in SiO2 and Al2O3, studies of their geopolymerization potential are rare. Thus, the illite/smectite clay of Friedland (NE Germany) was calcined (850 °C) and ground to form a reactive metaclay and then mixed with synthetic gibbsite (to test the effect of Al-concentration) and 6 molar NaOH or KOH, in order to study their geopolymerization at 25, 50 and 75 °C within 28 days. The raw clay, the precursors, and the geopolymers were characterized by XRF, XRD, SEM-EDX, Flame-AAS, nitrogen adsorption and compressive strength test. 25 °C was too low to initiate the geopolymerization of illite/smectite. Increasing the curing temperature increased the reactivity of meta-illite/smecite. Si and Al dissolution was confined to the first 24 h, followed by the hardening of the geopolymers within 28 days. At 50°C, KOH-activation formed amorphous and mesoporous aluminosilicates, which significantly cemented the particles and agglomerates of the metaclay. Consequently, geopolymers with high compression strength (~38 N/mm2) were formed. Adding 10 wt% Gibbsite (precursor Si/Al = 2.1) to the metaclay strengthened the formation of amorphous aluminosilicates and increased the compression strength of the geopolymer by 20 % from 38 - 45 N/mm2. At 75 °C, the reactivity of the metaclay in NaOH was higher than in KOH. NaOHactivation at that temperature formed geopolymers with high compression strength (~30 N/mm2) due to the cementation by microporous phillipsite (K-, Na-zeolite) crystals. Thus, alkali-activation of the calcined and ground meta-illite/smectite from Friedland form high strength geopolymers under hydrothermal conditions.
The research aims at assessing the impacts of the Benefit Sharing Mechanism (BSM) pilot policy on the socioeconomic factors and natural-resource management in the co-management area between the Bach Ma National Park and the Thuong Nhat community. This is a new approach in Special-Use Forests (SUFs) management in Vietnam, which is needed to assess the scaling up of a national policy on co-management of SUFs in the future. A case study was undertaken in the Bach Ma National Park, which was one of the two national parks chosen to pilot the BSM policy under the Prime Minister’s Decision No 126 (Government-126 2012). In this study, both qualitative and quantitative data was collected on BSM implementation schemes; their impacts on local natural-resource use; local awareness of rights, benefits, and responsibilities when participating in the BSM; and local perspectives on the BSM’s achievements, failures, and future potential. Analysis revealed that the local community strongly supported the BSM implementation in the Bach Ma NP, displaying a high level of demand for the measures and significant involvement. Furthermore, thanks to the local people’s participation in the BSM implementation, their household incomes increased and their awareness and practices of NTFP sustainable use and forest protection in the co-management area improved”. The BSM implementation also exposed three main areas of weakness. These included poor compliance with the sustainable-harvest regulations, the apparent over-complexity of the the harvest-application procedures, and the users’ low contributions to the village fund after the NTFP harvest. The current research revealed that, although the local awareness and compliance with the BSM procedures increased annually after BSM implementation, the level of self-management and compliance was still quite low and needed to be improved. Furthermore, some conflicts have arisen between NTFPs users from village to village in Thuong Nhat and between local traders and NTFP collectors. Besides, the research identified two major negative practices: overexploitation of NTFPs and taking advantage of the NTFPs harvest to cut trees or trap animals. This dissertation presents various possibilities for improvement of the BSM implementation through (i) raising local people’s awareness; (ii) simplifying BSM procedures; (iii) clarifying incentives and tasks of BSM actors to enhance co-patrolling and monitoring activities; and (iv) creating good incentives either based on the livelihood program for those who actively comply with the BSM regulations or direct payments to those who join forest-protection activities. Finally, the research scrutinized certain challenges to future duplication of the BSM in other SUFs in Vietnam. To expand the BSM approach to other SUFs, the Ministry of Agriculture and Rural Development needs to develop a guideline for BSM implementation to encourage the relevant stakeholders’ involvement. The guideline for national BSM implementation should take account of the differences between local contexts, as well as create the necessary, flexible regulations to be applicable in practice. Therefore, based on the guideline, additional steps are necessary for the development of appropriate specific measures in the course of the BSM implementation at the provincial and local levels.
All-embracing human activities have transformed one-third to one-half of the Earth’s land surface. There is a strong correlation of human well-being with ecosystem function, including poverty alleviation programs as well as enhancements of the health sector. To assess and evaluate the progress and outcome of initiatives stringent periodic observation is necessary. The presented approach combines the strengths of remote sensing and GIS analysis with social research applications. The Bach Ma National Park as an area under investigation was designated as protected area in 1991 and extended in 2008. The national park is uninhabited, but in the surrounding buffer zones approximately 62000 to 79000 people live in rural areas and in mostly impoverished conditions. The comprehensive nature conservation efforts of the Vietnamese Government during the last two decades has led to growing forest coverage of both plantation and natural forests. Nevertheless, the decreasing biodiversity and ongoing illegal logging and hunting activities in the national park are seen as major threats to conservation initiatives in the future. The remote sensing component consists of an analysis of a time series of Landsat images with seven steps ranging from 1973 to 2010. The resulting land cover analysis had 13 different classes. The accuracy assessment revealed an overall accuracy ranging from 84 to 90%. The basis for the second monitoring component was the Landsat images. A total of 25 different landscape metrics on the landscape, class, and patch level were calculated by FRAGSTATS. The third monitoring component is itself divided into two parts. This part consists of a qualitative social research study with 26 expert interviews. The second part consists of 61 standardized questionnaires and an evaluation by SPSS. The assessment reveals a more or less stable forest cover, but with a considerable degradation process during the last four decades. Urban areas outside of the national park have increased in size considerably. For dense and medium forest patches an increasing fragmentation and isolation of patches was observed. Patches of natural forests and habitats of thousands of species have declined dramatically, a trend that is related to a decreasing core area characterised by its undisturbed conditions. The Landsat images and landscape metrics reveal the major differences between the national park and surrounding areas. Despite extensive alterations near the border, remaining forest patches in the national park are still bigger and less fragmented. Nevertheless, the third monitoring component revealed undiscovered changes in the forest beyond the possibilities of used images and metrics. It includes illegal logging and hunting activities. Non-timber forest products are similar to faunistic species collected for both the subsistence of the local residents and associated markets as important sources of income. Based on this bisection, local residents as well as certain strangers are responsible for the activities in the forest. The plan of national park management is to intensify existing monitoring and patrolling in the forest to limit the exploitation and impact in relevant zones. Furthermore, the importance of a network of protected areas has attracted increasing attention. The assessment of the questionnaires reveals that deforestation and also reforestation were the key aspects of historical land cover change. Additionally, for the local residents the conversion of forests into arable land as income alternative is of major importance. Capacity development is not only one priority of the Bach Ma management but also of the international community for all of Vietnam. The tourism industry, one of the most promising opportunities of recent years, stands to support both national park management as well as the local residents. For local residents the extraction of non-timber forest products is an essential portion of the income. The current pilot policy 126/QD-TTg in the extension zone of the national park and research on an appropriate sharing mechanism is of the utmost importance. The established and presented monitoring components are cost-effective and can be used to regularly assess the land cover change of a protected area. They can be implemented together or individually into existing monitoring schemes. A smart combination of pre-existing datasets is necessary to overcome the inconsequential amount of money for monitoring procedures. Supplemented by socio-economic monitoring and the demands as well as impacts of human activity need to be integrated. These extensive requirements for prospective monitoring are only feasible with comprehensive and reliable collaborations.
Liu–II coal pit is a typical example of China’s deep coal mines which is seriously threatened by groundwater inrush from the underlying carboniferous Taiyuan limestone formation. An exhaustive data set of this confined aquifer exists. The aquifer lies 45 m∼ 60 m below the major coal seam. A traditional artesian aquifer test has been performed in order to assess the hydraulic properties, e.g. transmissivity (T) and storage coefficient (S). This artesian aquifer test is conducted with four simultaneously operating production wells while the discharge of each production well varied with time. The results of this test suggest that the aquifer is heterogeneous. Therefore, the according problems are: (1) how to analyze the artesian aquifer test with linearly declining discharge; (2) how to deal with multiple production wells in an aquifer test; (3) how to adequately consider aquifer heterogeneity. Thus, the objective of this thesis is to solve these problems. 1) As opposed to classical above-ground pumping tests, it is difficult to control the discharge rate of the production well in a deep mine artesian aquifer test since the hydraulic pressure is extraordinary high. Moreover the discharge rate won’t descend rapidly to zero, thus the analytical solution of Jacob and Lohman (1952) type curve for the artesian aquifer test will not be applicable. It is more reasonable to analyze the test as a pumping test with variable discharge. It is considered to rebuild a hydrogeological conceptual model which is similar with Theis (1935) model but with the variable discharge. A general equation for any discharge variability is given. Its application for the linearly declining discharge is presented subsequently, and a type curve of this equation with linearly declining discharge is given as well. After that, a simple numerical model is built by FEFLOW to simulate an artificial pumping test with the linearly declining discharge by assigning different parameter sets for transmissivity and storage coefficient. The type curve method is applied to evaluate transmissivity and storage coefficient for the linearly declining discharge well. The deviation between the given values of transmissivity and storage coefficient in FEFLOW and the values of those calculated by matching point are sufficiently small. Thus, when the discharge of production well declines linearly, a type curve method as an empirical method is reasonable and gives satisfactory values of these hydrogeological parameters. 2) In some cases, it is necessary to conduct a pumping test (or an artesian aquifer test) with several pumping wells (or production wells) which work simultaneously in order to discharge maximum quantity of groundwater. Normally, the superposition method or numerical simulation is applied to analyze the test result. However, a new approach called “Well Generalization Method” is defined and analyzed in this thesis. It is an easy–to–use approach for hydrogeologist to estimate the aquifer parameters while conducting an aquifer test. Since the key point of this approach is using a generalization well to substitute the pumping (or production) wells, it is obvious that this approach will generate the estimated error of parameters. Accordingly, several scenarios are analyzed and discussed based on the artificial type aquifer designed in FEFLOW. A homogeneous aquifer and a heterogeneous aquifer which is generated by geostatistical stochastic simulation technique (see 3)) are discussed separately. As a result, this approach is feasible and applicable under some conditions when the calculated observation well is arranged more than about 2.5 times the scale of the multi–pumping–wells field away from the center of the multi–pumping–wells field, furthermore, the maximum deviation of drawdown resulting from these observation wells will be less than 0.5 m, and the estimated value of transmissivity will be 0.44% smaller than real value. 3) Finally aquifer heterogeneity is addressed, in order to check the introduced method for applicability under realistic conditions. It has been described that aquifer heterogeneity plays a major role in hydrodynamic processes (e.g. de Marsily et al., 1998). Geostatistics which is considered as a useful tool for characterizing the spatial variability of transmissivity is applied to solve this problem. Based on the results of the artesian aquifer test conducted in Liu–II coal pit, a model of spatial variability of transmissivity is developed. Sequentially, the variogram model is applied in ordinary kriging to interpolate the transmissivity distribution, and in sequential Gaussian simulation to simulate a random field of transmissivity data in order to reflect its small scale variability. A comparison of the results of estimation and simulation of transmissivity indicates that the simulated values better reflect the spatial variability, reversely, the estimated values are much smoother.
The UNESCO Man and the Biosphere Programme has been active in South Africa for almost 20 years. The country currently has six designated biosphere reserves with a few sites in various stages of the nomination process. Within the South African context, agencies are using a series of seemingly different instruments to practice landscape-scale management. The UNESCO biosphere reserve concept sometimes finds it difficult to obtain prominence amongst these different landscape initiatives. Biosphere reserves are special sites wherein sustainable development is promoted. For this reason, the biosphere reserve concept has much to offer towards long-term sustainable socialecological land management. In our modern age of population growth, dwindling natural resources and a general disconnectedness of humans from nature due to large scale urbanization, there is an urgent need for innovative ways in which to showcase sustainable living practices. South Africa has limited natural, economic and social resources and therefore needs to prioritize where these resources could best be allocated. This dissertation comprises the history of the MAB Programme in South Africa, as well as a multicase study on five existing biosphere reserves. Results from this study indicated that not all biosphere reserves are equally effective in their implementation of the three functions of biosphere reserves and that all biosphere reserves in South Africa face an uncertain future due to pressing challenges. Collective results of the multicase study as well as literature reviews were used to inform options for the future effective implementation of the MAB Programme in South Africa. Options that could contribute towards effective biosphere reserves include more sustainable funding support, and community-based demonstration projects. In addition a new suite of criteria to inform the selection of future biosphere reserves was developed. Biosphere reserves need to be optimally located in order to secure long-term efficiency and effectiveness. These sites need to be representative of biodiversity, efficiently managed and persistent in the long run. Presently in South Africa, new sites for biosphere reserves are nominated in an ad hoc manner. Should their locations be selected discerningly, they offer many benefits to the South African social and environmental landscape that should be recognized and utilized. The final suite of selection criteria are structured according to four subsections, namely a general section that addresses national matters of general concern to the MAB Programme, and three sections covering the three biosphere reserve functions of conservation, sustainable development and logistic support. This suite of biosphere reserve selection criteria for South Africa is being put forward for deliberation and discussion at local, provincial and national level. It has the potential to be of valuable assistance in selection processes for future effective and efficient biosphere reserves that will proudly earn their place in the South African landscape as “special places for people and nature”.
Governance and Management of Tourism in two Biosphere Reserves in Ecuador: Galapagos and Sumaco
(2014)
Tourism is multi-faceted phenomenon and various stakeholders, levels of government, and sectors are closely interlinked. Governmental and non-governmental institutions, local communities, diverse professionals, and different sectors and tourists do show various perspectives about the management of tourism. In this dissertation, a comprehensive analysis on the current situation of tourism in two biosphere reserves (Galapagos and Sumaco) in Ecuador is presented. Tourism is considered as one of the key strategies to promote environmental conservation and socio-economic development of local communities living in these places. UNESCO biosphere reserves are protected areas of extraordinary natural and cultural value, conceived as places for reconciliation between conservation and development. The concept of sustainable tourism can be seen as an umbrella that unites various forms of tourism in these protected areas (e.g. ecotourism, community-based tourism). The primary objective was to evaluate the main factors of success and failure in the management of tourism and its contribution to biodiversity conservation. Thus, a detailed review of the legal, political, and institutional framework of the country and a description of the two biosphere reserves (physical, biogeographic, demographic, socio-economic, institutional and legal elements) was given. Data collection for the case studies (Galapagos and Sumaco) was performed by the combination of qualitative and quantitative methods. As for qualitative tools, in-depth semi-structured interviews with the main stakeholders in both biosphere reserves were applied. Experts and specialists in the management of protected areas, as well as representatives of different sectors directly and indirectly associated with tourism were interviewed. Moreover, surveys were applied to two different target groups. Tourists were surveyed in order to establish their socio-demographic profile, travel preferences, and degree of knowledge about sustainable tourism, as well as their perception of the sustainability of tourism in the destinations visited. Furthermore, residents in both reserves were surveyed in order to find out about their socio-demographic characteristics, their main economic activities for supporting themselves and their attitude towards tourism, their level of knowledge about biosphere reserves, and their perception about advantages or disadvantages of living in a biosphere reserve. In general, although tourism is a concept that could be developed in accordance with the environment in these natural areas, in the case of Galapagos it is one of the main risk factors for the conservation of biodiversity in the archipelago due to the increasing number of tourists. In contrast, in Sumaco tourism could be an important sustainable alternative to mining, oil extraction and hydroelectric projects, which are the current threats to the conservation of the area. From the environmental point of view, there are serious problems in both reserves, mainly linked to the contamination of water resources. Such pollution imposes risks to the health to both, residents and tourists. The lack of freshwater is particularly critical in Galapagos, given its insular habitat. The invasion of exotic species in Galapagos is one of the most serious threats to the conservation, while deforestation in combination with illegal logging and mining activities is the greatest danger in Sumaco. In terms of sociocultural factors, migration processes undoubtedly shape the attitudes and values of the current population in both reserves. In Galapagos most residents are immigrants, whereas in Sumaco a significant portion are Kichwa people who belong to the area’s native population. In general, the inhabitants in both areas have not yet developed a true environmental awareness. The distribution of human population groups is also associated with the different types of tourism. In both reserves, tourist services offered by local communities have low quality standards and are targeted on a market segment consisting of tourists with a low budget. Thus, the community revenues obtained from tourism are generally only a small percentage of the total tourism market. This situation is much more noticeable in Galapagos where large companies that operate luxury cruises and hotels gain most of their revenues from tourism. Many of them have their headquarters in the main cities of Ecuador and abroad, which means that they pay their taxes in those cities and not in the places where they operate. Inequality in the distribution of the economic benefits of tourism leads to a situation of frustration and discontentment among the residents of the regions involved. Despite this situation, tourism is still a profitable business and residents try to make the most of it, no matter the cost impacts. Temporary and illegal tourism activities is often the normal state of the things: unregistered houses that offer rooms for tourists, taxi drivers who offer tours without being in possession of permits, tourist boat owners, tour guides and even large tourist companies that operate without legal licenses. This situation inevitably leads to a decrease of the quality of services, an uncontrolled increase of business, a consequent dumping of prices and the overall decline of the destination. Ultimately, this means fewer tourists, more environmental degradation and less economic benefits for residents. In this context, there is a serious conflict between the local community and large foreign companies. Governance and management of tourism are essential elements to ensure its development in a sustainable way. The country has a large number of laws, rules, regulations, and plans that regulate the development of sustainable tourism legally and institutionally, especially in protected areas. However, monitoring and law enforcement are major constraints for achieving proper management of tourism. This problem is particularly noticeable in small communities such as Galapagos and Sumaco where interpersonal relationships of kinship and friendship are close, which complicates control and regulation. There are some serious limitations regarding the technical and logistical capacity of the institutions responsible for controlling and managing the tourist activity; they consist mainly in the lack of staff and funding. Galapagos, given its special status, has increased the number of funding managers and staff members for controlling and management, but in many cases, these people are not fully qualified for their positions. Sumaco has only few tourism experts who can help to develop the tourism. The coordination and planning among all stakeholders involved in tourism is still a work in progress to ensure proper management of the tourist destinations. In any case, local communities are developing important initiatives in both biosphere reserves. After all, sometimes planning, coordination and local activities do not necessarily coincide with the national agenda. In general, in both biosphere reserves it is necessary to ensure higher standards of education, both formal and informal. Also it is urgent that the government as a regulating entity ensures the equitable participation of local communities in tourism benefits, control, monitoring, and law enforcement. Moreover, there is the need to encourage and ensure integrated planning of tourism in the different levels of government: local, regional, and national. Sustainable tourism means that the protection of cultural heritage and natural resources is granted at least the same level of importance as the involved economic interests. The unique nature that currently attracts tourists to Galapagos and Sumaco should be preserved not only for ensuring the continuity of the tourism activity itself, but also in order to safeguard biodiversity and natural resources for the coming generations. Responsible tourism practices which care about their social and environmental impacts are not necessarily opposed to economic interests. On the contrary, they need each other for a long-term development.
Tourism is booming on global level since many decades and developing countries often capture tourism as a lever to push up their economy. Many regions in Vietnam invest lots of money in this development hoping to change the traditional economic structure. Located in the North Central Vietnam, about 170 km from Ha Noi capital to the south at the coastline, Sam Son is known as an ideal location for holiday makers. Currently the number of tourist has been counted to millions. Realizing its potential, the local authorities decided to enlarge and improve tourism to become the biggest tourism center in the North Central part of Vietnam. As many mass tourism destinations, Sam Son is facing several hidden drawbacks, which are generated by a (too) fast growth. Thats why unexpected problems may occur very soon. One path to mitigate weaknesses and to strengthen the positive impacts of tourism is to develop tourism in a more sustainable manner. As the very first step Sam Son needs to delineate a proper strategy and to establish a powerful "Destination Management System". Although several studies have been conducted already, the destination lacks reliable empirical data. This research intends to fill the gap by supplying concrete information with specific focus on “making tourism more sustainable”. In the study methodological triangulation has been applied to collect data and information. Besides literature review and secondary data analysis, two surveys - statistically well secured - have been conducted: A household survey with more than one thousand questionnaires to record the situation and opinion of local people and a visitor survey with 1139 face-to-face interviews to collect structural data about current guests in Sam Son as well as to explore their behaviour. Moreover expert and stakeholder interviews were included to supplement the information basis. As the research acquired the information directly from local people and from tourists by face-to-face interviews several weaknesses could be unveiled which official statistical data cannot show. There are three facets out of balance in terms of economic benefit: Compared with the political awareness and the financial support the tourism sector does not ensure the livelihood of an adequate number of people; the economic benefits from tourism are very unequally distributed and also the spatial dimension indicates a strong imbalance - only people living directly in the core area of tourism participate in tourism sector, the positive impact of tourism does not reach till the outskirts. In addition social and environmental problems are recognized by a majority of local people as consequences of tourism in the region. Regarding the touristic demand side a very low level of satisfaction has been detected: A small variety and low quality of touristic offers are the main reasons of dissatisfaction. The most exiting finding is that tourists treasure environment in the destination, whereas this aspect is underestimated in the locals view. In addition, tourists are really willing to pay for an improvement of environmental and touristic quality! Even if the amount of voluntary payments is very low, the total sum can enable the local government to develop the destination in a very proper way. Although this is a case study the results deliver valuable information and furthermore a concrete delineated roadmap for all destinations, which are in the same situation as Sam Son today. It is an example how to analyze and evaluate the present condition and how to continue in a proper way towards a more sustainable tourism development.
This thesis aims at improving the current representation of adaptation in economic frameworks of climate change by a) accounting for the time-dependent evolution of the adaptive capacities of countries and b) quantifying unwelcome feedbacks of the adaptation process. In this context, it is proposed that economic assessments of climate change incorporate adaptation as a cyclic and phase-dependent process while devising their cost methodologies. A phase-dependent process acknowledges the existence of adaptation barriers while a cyclic process accounts for potential unwanted feedbacks of adaptation. By analyzing economic assessments against this framework, it is shown that dependencies between phases of adaptation and phases altogether are often disregarded. Furthermore, potential negative consequences associated with adaptation are rarely considered and adaptation is generally assumed to be unconstrained. The assumption of unconstrained adaptation is only acceptable in the context of high adaptive capacity. This concept was further investigated through a review of vulnerability assessments regarding their operation of the adaptive capacity component. It was found that adaptive capacity is mostly equated to proxies that reflect the knowledge, financial and livelihood capacities of the system under analysis. With this theoretical considerations in mind, a dynamic representation of adaptive capacity was elaborated at a country-level. The Human Development Index (HDI) was used as a proxy of the adaptive capacity of countries and its evolution in time extrapolated. The time required for countries to achieve developed world standards of human development was then estimated. The results indicate that between 2005 and 2020, half of the world population will live in countries with low adaptive capacity. This percentage is then progressively reduced to 15% in the year 2050, with marked regional differences. The time required for a country to achieve an appropriate level of development sets a clear constraint on when, and to what extent, the country can engage on climate change adaptation. This does not imply that adaptation will not take place before development occurs. Rather, it calls for adaptation options to be tailored in order to t the current and future adaptive capacities of countries. Obtaining higher levels of adaptive capacity is likely to be associated with negative consequences for the climatic system. The statistical relation between HDI and per-capita emissions of countries was established and future projections made. Between 2010 and 2050 approx. 300 Gt of CO2 are estimated to be associated with the increase of adaptive capacities of current developing countries. This value represents about 30% of the allowed CO2-budgets to restrict global temperatures to an increase of 2 degrees by 2100 compared to pre-industrial times - conditional to a 25% risk of failing to meet the target. For the case of sea-level rise, the modelling framework DIVA (Dynamic Interactive Vulnerability Assessment) was used in order to illustrate the drawbacks of a simplistic representation of adaptation. The results show that adaptation via the construction of protective infrastructure might be economically feasible for particular countries. For others, modeled results fail to provide a clear choice between adaptation or inaction. The assumption of unconstrained adaptation resulted in the valuation of costly protection options whose financial and knowledge requirements can be at odds with the capacities of some coastal countries - namely developing countries. Further, infrastructural protection as adaptive measure to prevent coastal damages can have the counter-productive effect of raising the amount and value of assets at risk. This is a direct result of DIVA disregarding the potential unwelcome feedbacks of adaptation itself. In conclusion, the full potential of economic assessments of climate adaptation is likely to remain unlocked as long as adaptation continues to be misrepresented. The methodologies discussed in this work provide a way forward to alleviate this deficiency in forthcoming assessments. For the case of sea-level rise, the modeling framework DIVA (Dynamic Interactive Vulnerability Assessment) was used in order to illustrate the drawbacks of a simplistic representation of adaptation. The results show that adaptation via the construction of protective infrastructure might be economically feasible for particular countries. For others, modeled results fail to provide a clear choice between adaptation or inaction. The assumption of unconstrained adaptation resulted in the valuation of costly protection options whose financial and knowledge requirements can be at odds with the capacities of some coastal countries - namely developing countries. Further, infrastructural protection as adaptive measure to prevent coastal damages can have the counter-productive effect of raising the amount and value of assets at risk. This is a direct result of DIVA disregarding the potential unwelcome feedbacks of adaptation itself. In conclusion, the full potential of economic assessments of climate adaptation is likely to remain unlocked as long as adaptation continues to be misrepresented. The methodologies discussed in this work provide a way forward to alleviate this deficiency in forthcoming assessments.
Urban Green Areas – their functions under a changing lifestyle of local people, the example of Hanoi
(2013)
Hanoi is a rapidly developing city - in terms of area, population and economy. It also has to face social and environmental problems that often accompany the fast development of a city. Increasing environmental pollution leads to a decrease in living conditions, such as clean water, housing, social services, etc., for most of the city’s inhabitants. Other well-known social problems in cities worldwide also occur in Hanoi nowadays, for example inequality, food supply, and unemployment. In addition, the society is altering; lifestyle- change is a permanent process. Today, it seems that the changing process in Asian countries is rather leap-frogging than continuously. Although many research projects concerning to urban green areas in Hanoi have been completed recently, less is known about utilization of parks&gardens in a practical and systematic way. This study aims at contributing to fulfills the gaps with up-to-date facts and figures of parks’ utilization in the inner city of Hanoi. Based on “grounded theory”, triangular methodology was applied to collect empirical data in four main parks in the inner city of Hanoi namely: Thong Nhat, Bach Thao, Hoan Kiem, and Lenin. Scientific observations, visitor countings were done in 2010-2011; including 2143 face-to-face interviews to park users covering the course of the year and a small online-poll of 113 responses. Thirteen interviews with experts have been done in several phases and taken into account for discussing and testing hypotheses. Empirical results have shown that utilization of the parks is in abundance in terms of the use - numbers as well as activities. A comparison between the courses of the day for parks in Berlin and Hanoi shown that the time of using parks in Hanoi is earlier in the day. In details, there is 25% and 1.4% of total daily visitors went to parks in Hanoi and Berlin,, respectively. However, the biggest peak in park-visiting time for both cities is in the afternoon. The findings also clarified that students and retirees are the major users even though there is some different in structures of park user among the four parks. The length of stay depends on how large and interesting a park is. In this aspect, Hanoi parks are very poor in facilities showing by a long list of missing facilities in the parks. However, as there is no alternative, parks in Hanoi still attract a high number of visitors. In general, results from this study have shown a close relationship among socio-economic and political situations in Vietnam with UGAs and its utilization. Influencing factors on parks’ utilization were also indentified, which are social changes, lifestyle changes, economic situation, conflicts in land usage, and maintaining cost for UGAs. Three given hypotheses were confirmed: i) the demand of public UGAs in inner Hanoi will grow mid-term and increase strongly long-term; ii) Hanoi’s residents will claim strongly for more parks in the future; ii) The number of conflicts inside the area of UGAs, among the visitors will occur very soon and require a specific master plan for the development and the management of UGAs. Finally, based on the weaknesses of UGAs in Hanoi recently, two groups of recommendations were also suggested to improve UGAs. Firstly, in terms of quality – quantity: • Retain each square meter of green space as UGA – do not unblock any green space for construction; • The existing UGA have to be well maintained. Secondly, in terms of management – planning: • Elaborate a UGA-masterplan for (inner) Hanoi; • Keep UGA management in the responsibility of public bodies; • Implement participation of affected population defector in the process of planning and management (as it has already been written in planning guidelines); • Be aware of potential conflicts among park user groups; • Establish an UGA monitoring system – involving regular (or even permanent) countings based on up-to-date technology; Realize horizontal partnering structures.
Understanding the interaction between climate variability and ice sheet behavior is critical due to scenarios of future climate warming and the consequent contribution of Greenland ice sheet melting to sea-level rise and its potential to influence thermohaline circulation. This thesis investigates the role of ocean forcing by the West Greenland Current (WGC) on the dynamics of West Greenland ice sheet behavior, with focus on Jakobshavn Isbræ, in the Disko Bugt area of central West Greenland. High-resolution sediment cores, obtained during a cruise of the RV ‘Maria S. Merian’ in 2007, provide a long-term Holocene perspective on climate variability off West Greenland. These records cover the last 8000 years with increasing resolution through to periods of historical and instrumental data series. Paleoenvironmental reconstructions, based on the calcareous and agglutinated benthic foraminiferal assemblage, reveal significant variations in the water mass properties (e.g. temperature and salinity) of the WGC. From 8 to 6 cal. ka BP, a relatively warm WGC enhances meltwater production (ice retreat) in Disko Bugt. Holocene ‘thermal optimum-like’ conditions prevailed from 5.5 to 3.5 cal. ka BP, associated with minimum ice sheet extent in eastern Disko Bugt. Long-term cooling of oceanographic conditions is recognized from c. 3.5 cal. ka BP towards the present day. Superimposed on this millennial scale cooling trend, centennial scale variability within the WGC is reconstructed: i) the 2.7 cal. ka BP ‘cooling event’; ii) the Roman Warm Period; iii) the Medieval Climate Anomaly; and iv) the Little Ice Age. Over the past 100 years, oceanographic conditions remain relatively cool and multidecadal variability in the WGC’s ocean temperatures show close correlation with the ice marg in position of Jakobshavn Isbræ and phases of the Atlantic Multi-decadal Oscillation (AMO). Cold (warm) phases correlate with stabilization/re-advance (retreat) of Jakobshavn Isbræ and a negative (high) index of the AMO. It has been demonstrated that variations in ocean temperature are an important factor that influence ice sheet behavior on a range of times scales, underlining the close coupling of ice-ocean interactions during the Holocene. Warmer ocean temperatures influence the stability of marine terminating ice sheets and glaciers, causing basal melting and glacier acceleration, whereas ocean cooling supports stabilization and advance of ice margin.
The dissertation aims at developing means to integrate conservation and development in biosphere reserves in Madagascar. Despite a multitude of concepts such as UNESCO biosphere reserves, Integrated Conservation and Development Projects and community-based natural resource management, gaps between conservation and development remain to exist. In a qualitative case study in Mananara-Nord and Sahamalaza Iles-Radama Biosphere Reserves in Madagascar data was collected on biosphere reserve management, local use of natural resources and socio-cultural aspects that influence natural resource use. Furthermore, natural values local people associate with the forest were investigated. Analysis revealed that management capacities constitute a limiting factor in biosphere reserve management. Collaboration between management, local people and international organisations fosters the achievement of both conservation and development. However, collaboration is only possible if (i) clear rules are formulated and (ii) partners have a vision in common. Based on the theory of social capital, newly introduced and locally existent rules/institutions having an influence on the use of natural resource were categorized in bonding, linking and bridging social capital. Furthermore, the perception of natural values was classified in instrumental and non-instrumental values and assigned to ecosystem services identifying the importance of nature for human well-being. With the capabilities approach Amartya Sen defined human well-being as the achievement of those capabilities a person considers valuable. This includes aspects that assure livelihoods on the one hand and aspects that are conducive to well-being on the other, thus both being relevant for development. In the dissertation capabilities are based on both instrumental and non-instrumental natural values and consequently offer an opportunity to demonstrate and characterise the relationship between nature and human well-being. Social and natural values provide orientation for a biosphere reserve management. The category bonding social capital (social values) describes local socio-cultural aspects in communities and their importance for collaborative processes. Natural values provide the management with guiding principles to foster nature conservation and to integrate locally existent capabilities. Supporting and furthering these capabilities enables the development of new capabilities of all concerned persons. The dissertation demonstrates various possibilities to build bridges between (i) nature conservation and development, (ii) natural and social sciences, (iii) formal regulations and local socio-cultural aspects and (iv) diverse actors. Implementation of a social monitoring is recommended together with local stewards and Malagasy students to collect information about the perception of natural and social values and use them as guiding principles for biosphere reserves. Collaboration with national and international scientific institutions can foster this process.
The main objective of this research was to enhance the understanding of the inte¬ractions of bentonite with iron in the near field of a HLW-repository. One target was to investigate natural Fe-rich bentonites as a possible analogue. Another topic was to recognize the mineralogical interaction of bentonite with iron powder simulating the contact of bentonite with steel containers (thermodynamic approach). An additional objective was to explore the idea that bentonites have a specific dissolution potential (kinetic approach). In order to take the thermodynamic approach, compacted MX80 bentonite and Friedland clay were used as starting materials for clay/iron interaction experiments in per¬colation systems (Clay/Iron-ratio = 0.1). The natural processes were studied by examining a tropical wea¬thering profile of serpentiniz¬ed diabase from the Thanh Hoa province of Vietnam. The kinetic approach was taken by investigating a series of well characterized bentonites, 9 from API-standard series, 12 from the BGR-collection and 4 others, all of them saturated with deionized water (liquid/solid-ratio = 10/1) and NaCl 1N solution (liquid/solid-ratio = 4/1) for 30 days, followed by exposing the soft gels to mechanical agitation by overhead shaking corresponding to two energy levels (20 rpm and 60 rpm). XRD and TEM – EDX measurement were the major analytical techniques applied in this research, with FT-IR and XRF analyses as additional tools to characterizing the structure and composition of the smectites. Thermodynamic Approach MX80 bentonite and Friedland Clay clearly show that chemical and mineralogical changes have occured in the reaction products. They are exemplified by the neoformation of serpentine and chlorite in certain mixed layer phases. The smectite in the reaction products had also undergone changes especially in the constitution of the octahedral and tetrahedral sheets as well as in the interlayer space. These alterations were evident by the difference in key peak positions and ratios of XRD-patterns, and by TEM-investigations, as well as by different positions and intensities of FT-IR-bands of octahedral and tetrahedral features. The alteration was also seen in the bulk chemical composition data (XRF). MX80 bentonite and Friedland clay show various types and stages of alteration under different experimental conditions. The alteration can be described as “illitization” in open reaction systems and “smectitization” in closed reaction systems. The degree of alteration was controlled by the degree of chemical activities (ion strength, Fe- & Si-activity, con-centration). Higher reactivities give higher degrees of dissolution and release of Si from clay minerals. The oxidation of native iron (Fe0 → Fe2+) was recognized as the main driving force for dissolution, but also the oxidation of Fe2+ (Fe2+ → Fe3+) appeared to reverse an open to a closed reaction system by increased Si-pre¬cipitation. The thermodynamic modelling of C/I-experiments by Mingliang Xie (GRS mbH) verified identified mineralogical alterations in the reaction products. Generally, the contact with metallic iron caused a strong increase in dissolution potential. The reason for this is the reducing potential of oxidation of iron which raised pH to become alkaline and increase dissolution of Si from clay particles. The mineralogical transformations recognized in the experiments, such as the neoformation of serpentine and chlorite phases, were also observed in the tropical weathering profile of serpentinized diabase. The wellknown fast development of Fe-rich montmorillonite in alteration of ultramafic rocks (e.g., Schnellmann, 1964) was also identified by mineralogical investigation of the weather¬ing profile. This confirms that smectitization is linked with higher Fe-activities also in nature. Fe2+ was present in this system and during oxidation acted as driving force for alteration. The reduction potential of Fe-oxidation caused an increase of pH into alkaline conditions. Kinetic Approach The hypothesis that smectite clays have a specific dissolution potential emanated from the study. This would mean that high amounts of Fe and Mg in the octahedral sheet can accelerate alteration in agreement to what was early proposed by Cicel & Novak (1976). The larger ion diameter of Fe and Mg in comparison with Al may well be responsible for a higher sheet stress, which would facilitate dissolution of smectites. The idea proposed Kaufhold & Dohrmann (2008) concerning a mechanism that makes Ca- and Mg-cations in the interlayer space stabilize quasicrystals is also supported by the present study. The performed investigation indicate which mechanisms that serve to protect smectites from undergoing alteration and which promote alteration. Stable smectites, i.e. those with a low specific dissolution potential, were called here “Sleepers”, while fast reacting bentonites, which have a high specific dissolution potential, were termed “Sprinters”. Smectites react with different rates of reaction in laboratory experiments. As said, each smectite sample has its specific potential for dissolution and this potential is controlled by the composition of both the octahedral sheets and the interlayer space. Increasing amounts of octahedral Fe and Mg compared to octahedral Al increase the specific dissolution potential. This potential is also affected by the ion radius, implying that the larger ion radius of Fe and Mg compared to Al increases the mechanical sheet stresses in the octahedral sheet. In summary, this means that, the investigations have confirmed the initial hypothesis concerning the impact of the composition of the octahedral sheet. It results primarily from the pH during the formation of the smectite clay and therefore serves as a geological fingerprint. The Al-Fe ratio in the octahedral sheet influences the stability of the interlayer: A) Aloct > 1.4 and Feoct > 0.2 (per (OH)2 O10) favour delamination of quasicrystals. The swelling pressure increases by a co-volume process between the delaminated layers wiht higher numbers of quasicrystals for Na-dominant population of the interlayer space (Laird, 2006). The microstructural components including both small and large particles and parts of them have a very small ability to move and undergo free rotation. Such Na-montmorillonites are consider as stable phases and have only a low specific dissolution potential. They are „Sleepers“. B) Aloct > 1.4 and Feoct < 0.2 or Aloct < 1.4 and Feoct > 0.2 (per (OH)2 O10) promote demixing of monovalent and divalent interlayer cations (Laird, 2006). In the case of Ca and Mg-dominant interlayers, quasicrystal can break Na-bearing interlayers and help to maintain the quasicrystal structure. Such Ca and Mg-mont¬morillonites can be also be taken as „Sleepers“ because of their low specific dissolution potential. Depending on the octahedral composition, certain cations in the inter¬layer can stabilize bentonites against mineralogical changes. Montmorillonites stabilized by high concentration of Na-cations were classified as belonging to category A, while montmorillonites stabilized by high Ca, Mg-cations in the interlayer sheet were grouped in category B. The classification of a smec¬tite into the categories A or B defined above can be best achieved by IR analyses that yield useful chemical information concerning the composition of the octahedral sheets. Smectites with Na as stabilizing interlayer cation (group A) have shown δAlAlOH-bands with increasing wavenumbers for increasing octahedral Al in FT-IR spectra. The other reaction type of smectite, with Ca, Mg-cations in the interlayers (group B), is characterized by a decreasing octahedral Al-amount for increasing wavenumbers of δAlAlOH-bands in such spectra. Also the FT-IR δAlFeOH-bands are different in the two reaction types of smectite. Increasing octahedral Fe-amounts were mirrored by decreasing wavenumbers of δAlFeOH-bands. However, smectites of group B do contain higher Fe-amounts for the same wavenumber than smectites of group A. Expected alteration of bentonite close and far from a steel canister In the early interaction of smectite-rich clay – the “buffer” - and steel, the system behaves as being chemically closed. Within the clay barrier, Si will be dissolved from clay mineral particles in accordance with its specific dis¬solution potential. The dissolved Si can stay by contributing neoformation of mont¬morillonite layers in mixed layer phases. The interlayer charge decreases by substitution of Mg by Al, which leads to an increase in the swelling pressure. Also minor Si-precipitation may occur if not all the dissolved Si is used up by the neoformed montmorillonite layers. Such precipitation of Si will cause cementation of some quasicrystals and lead to a reduction in porosity. Enhanced temperature and additional Fe-activity, representing an increased reduction potential, increases notably the amount of dissolved Si at the interface between bentonite and steel canister, and as a consequence there will be significant precipitation of Si. The resulting cementation of quasicrystals is ac¬com¬panied also by their collapse which induces broadening of pores. This caused the channel-like migration of infiltrating solutions and switches the system into an open one. Thermodynamic predictions indicate that “illite” will be generated close to the steel canister (via “illitization”) and kaolinite or pyrophyllite to be formed farther away (via smectitization). The “illitization” process results in higher interlayer charges and lower swelling pressures. In contrast, the formation of smectite reduces interlayer charges and promotes higher swelling pressures. At the end of the thermodynamic evolution, the swelling pressure will drop also far from the canister because kaolinite and pyrophyllite are non-swelling minerals. In both cases, the applications of so-called “Sleeper”-bentonites are required to slow the reaction progress. For designers of the engineered barriers in a repository, i.e. the canister and the “buffer” clay, some basic rules are recommend on the basis of the present study. Thus, the presence of native Fe or Fe2+-cations in the clay or in accessory minerals in it, or emanating from the canisters, will speed up the reaction process and make it extensive. Likewise, use of Fe-poor “buffer” clay, representing “Sleepers”-type are suitable for slowing down the reaction. Copper as canister material, and very dense Na-rich montmorillonite of group A as “buffer” seem to be ideal rather than steel/iron and less dense Ca-saturated clay.