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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.
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.
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.
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.
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.