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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.
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.
Für den erfolgreichen Erhalt von Natur und Landschaft sowohl in Schutzgebieten als außerhalb davon ist die Akzeptanz der jeweiligen Gebietsbewohner notwendig und ihr aktives Engagement hilfreich. Häufig gibt es jedoch Widerstand gegenüber Naturschutzmaßnahmen und wenige aktiv Engagierte. Ein Grund wird in der überwiegend naturwissenschaftlichen Argumention gesehen, die offenbar die Bedeutung von Natur und Landschaft für die Bevölkerung nicht ausreichend widerspiegelt. In der vorliegenden Arbeit wird daher der Frage nachgegangen, ob und wie ästhetische und emotionale Wertschätzungen das Portfolio von Argumenten für den Natur- und Landschaftserhalt bereichern können. Das empirische Material wurde im Rahmen eines Forschungsprojektes (gefördert von der Deutschen Bundesstiftung Umwelt, DBU, 2009-2012) gewonnen, dessen Ziel die Entwicklung und Erprobung von Erhebungsmethoden für ein sozioökonomisches Monitoring in den vier UNESCO-Biosphärenreservaten Mittelelbe, Schaalsee, Schorfheide-Chorin und Südost-Rügen war. Der zentrale Fokus der vorliegenden Arbeit mit soziologischer Forschungsperspektive liegt darauf, wie die Bewohner der vier untersuchten Biosphärenreservate ihre Region emotional und ästhetisch wertschätzen. Neben geographischen wurden vor allem die soziologischen Theorieansätze Social Identity Theory (SIT) und die Identity Process Theory (IPT) erörtert, um mögliche emotionale und ästhetische Argumente fundiert einordnen zu können. Es wurde eine quantitative CATI-Befragung mit mindestens 300 Interviews pro Biosphärenreservat auf der Grundlage einer Zufallsstichprobe durchgeführt. Die Daten wurden neben deskriptiven Untersuchungen mittels binär logistischer Regressionsanalysen und Varianzpartitionierungen als schließende statistische Methoden untersucht. Ein grundlegendes Ergebnis der Analysen ist, dass die Bewohner in allen vier Gebieten eine hohe regionale Verbundenheit aufweisen. Weiterhin scheinen Natur und Landschaft maßgeblich zur emotionalen Verbundenheit zur Region beizutragen. Außerdem stellte sich heraus, dass regionale Verbundenheit sowohl allgemein als auch mit explizitem Landschaftsbezug wichtige Themen für viele Menschen sind und kein Nischenthema einer speziellen Personengruppe darstellen. Denn zwar scheinen einige soziodemographische und andere Faktoren die emotionale Verbundenheit zu verstärken, diverse Parameter, wie etwa Geschlecht und ehrenamtliches Engagement, spielen dagegen aber kaum eine Rolle. Aus den Ergebnissen wurden folgende Handlungsempfehlungen für die Argumentation für Natur- und Landschaftserhalt abgeleitet: (1) Natur und Landschaft haben eine hohe emotionale und ästhetische Bedeutung für viele Bewohner, daher sollten alle raumwirksamen Aktivitäten umfangreich und so zeitig wie möglich erläutert und diskutiert werden. (2) Landschaftliche Vielfalt wird geschätzt und Natur und Landschaft werden nicht als rein stereotype Ansammlung von Landschaftselementen wahrgenommen, sondern mit regionsspezifischen Charakteristika. Wenn Maßnahmen in Natur und Landschaft zu diesen ästhetischen Werten beitragen haben sie ein großes Potenzial, die Unterstützung für Naturerhalt zu erhöhen. Daher wird empfohlen, diese Einflüsse der Maßnahmen besonders zu betonen. (3) Der Bildungsstand scheint grundsätzlich ein besonders wichtiger Faktor für die untersuchten Phänomene zu sein. Daher wird geraten, wenn möglich, die zielgruppenspezifische Kommunikation mit ästhetischen und emotionalen Argumenten sowie Angebote für ein Engagement so auszugestalten, dass Personen aus verschiedenen Bildungsmilieus erreicht werden. (4) Um Menschen für ein naturerhaltendes Engagement zu motivieren wird empfohlen, allgemein an der Region interessierte Personen zu suchen und anzusprechen. (5) Es scheint ratsam, bei der Formulierung von emotionalen Argumenten für den Erhalt von Natur und Landschaft auf den Begriff Stolz zu verzichten. Der Terminus findet unter Akademikern weniger Zustimmung, wenngleich sie eine hohe regionale Verbundenheit haben können. Der Heimatbegriff sollte nur benutzt werden, solange er sich auf kollektiv geteilte, eudaimonistische Werte bezieht und zukunftsgerichtet verwendet wird. (6) Neben der regionalen Verbundenheit können besonders die eudaimonistischen Werte Ruhe, Erholung und andere nicht mit Naturschutzzwecken konfligierende Freizeitnutzungen zielführend in der Argumentation für den Naturerhalt sein. Insgesamt wird für den Natur- und Landschaftserhalt tätigen Akteuren empfohlen, das offensichtlich bestehende Potenzial ästhetischer und emotionaler Argumente stärker zu nutzen und naturwissenschaftliche Argumente damit sinnvoll zu ergänzen. Die in dieser Arbeit diskutierten Ergebnisse liefern dafür eine fundierte Grundlage, da sich aus der nun vorliegenden vergleichenden Analyse von vier unterschiedlichen UNESCO-Biosphärenreservaten in Deutschland belastbare Empfehlungen ableiten lassen, die deutlich über die Untersuchungsgebiete hinaus anwendbar sind.
Die Arbeit beschäftigt sich mit den Bereichen Verkehrs- und Raumentwicklung sowie den demographischen und wirtschaftlichen Veränderungen. Dabei wurde mit der verknüpfenden Betrachtung zwischen alternativen Antriebskonzepten im Pkw-Markt und der Erzeugung von erneuerbaren Energien ein bisher nur wenig betrachtetes Forschungsfeld bearbeitet. Für eine derartige Betrachtung bieten sich die ländlichen Räume an, da der motorisierte Individualverkehr dort eine besondere Bedeutung besitzt. Die Mobilitätswende kann einen wichtigen Beitrag zur Regionalentwicklung für die Untersuchungsgebiete leisten, da so die regional erzeugte Energie als direkter Wertschöpfungsbeitrag vor Ort verbleibt. Darüber hinaus könnten die privaten Haushalte von einem nicht weiter steigenden Mobilitätsbudget profitieren. Somit kann die Mobilitätswende einen Beitrag zur Sicherstellung der verkehrsräumlichen Mobilität leisten und die Chancen zur Teilhabe am gesellschaftlichen Leben im ländlichen Raum verbessern. Aus ökologischen Gesichtspunkten erscheint die lokale Mobilitätswende ebenfalls vorteilhaft. Einerseits werden durch den Technologiewandel die Pkw-Emissionen gesenkt. Andererseits sinken die CO2-Emissionen durch die Verwendung regional nachhaltig erzeugter Energie. Für den erforderlichen Infrastrukturaufbau wurde ein Vorschlag gemacht, der einen Kompromiss zwischen Ausbauzielen, Kostenverträglichkeit und Flächenabdeckung darstellt.
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.