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Found 786 results.

Fragmentation of the international forest regime complex: multi-dimensional descriptions, explanations, steering consequences and polital options; The production and utilisation of forest regime fragmentation by bureaucratic politics

This project aims at analysing the influence of competing national and international bureaucracies on the fragmentation of the international forest regime complex (IFRC). Its objectives are: - describing the political dimension of fragmentation of the IFRC programme- explaining the political dimension of fragmentation based on the model of bureaucratic politics- analysing the steering consequences resulting from fragmentation - trans-disciplinary design of solutions for coping with political aspects of fragmentationBuilding on the bureaucratic politics approach these objectives will be pursued by testing the linking hypothesis: Interest and influence of the bureaucracies cause a fragmented programme of the IFRC. This programme supports the goal of profitable timber production but keeps the decision about biodiversity and CO2 sequestration open hindering the effective steering by the IFRC. The project develops an analytical framework consisting of the following independent variables: competing national and competing international bureaucracies, elected politicians, national and international non-state actors and media discourses. The fragmentation of the political programme of the IFRC is the overall dependent variable. This project will analyse the influence of bureaucracies and their coalitions on fragmentation at the international level as well as in national case studies in Sweden, Poland and Germany. The other independent variables will be covered by sub-projects 2, 3 and 4. The findings will be linked to the other political and to the economic and technic-ecological sub projects in order to contribute to the multi-disciplinary description and explanation of fragmentation and its steering consequences.

Schwerpunktprogramm (SPP) 1315: Biogeochemische Grenzflächen in Böden; Biogeochemical Interfaces in Soil, Quantification of active interfaces with respect to dissolved chemicals in unsaturated structured soil

During the first project period we developed a general approach to quantify soil pore structure based on X-ray micro-tomography Vogel et al. (2010) which is applicable at various scales to cover soil pores larger that 0.05 mm in a representative way. Based on this method we generated equivalent network models to numerically simulate flow and transport of dissolved chemicals. The existing network model was extended to handle reactive transport and infiltration processes which are especially critical for matter flux in soil. The results were compared to experimental findings. The original research question 'what does a particle see on its way through soil' could be answered quantitatively for various boundary conditions including steady state flux and infiltration. However, we identified various critical aspects of the proposed modeling concept which will be in the focus of the second period. This includes 1) the spatial arrangement of interfaces having different quality which is crucial for chemical interactions and pore scale water dynamics, 2) the realistic multiphase dynamics at the pore scale which need to reflect the dynamic pressure and movement of trapped non-wetting phase and 3) the parametrization of structural complexity which need to be developed beyond the measurement of continuous Minkowski functions to allow the development of quantitative relations between structure and function. These aspects will be explored in a joint experiments in cooperation with partners within the SPP.

DFG Trilateral collaboration Deutschland-Israel-Palestine: Wastewater from Olive Oil Mills in Israel and Palestine: Interactions with Soil, Organic Contaminants and Mechanisms of Incorporation into Soil

Due to the often practised uncontrolled disposal into the environment, olive oil production wastewater (OPWW) is presently a serious environmental problem in Palestine and Israel. The objectives of this interdisciplinary trilateral research project are (i) to understand the mechanisms of influence of the olive oil production wastewater on soil wettability, water storage, interaction with organic agrochemicals and pollutants; (ii) monitor short-term and long-term effects of OPWW land application in model laboratory and field experiments; (iii) identify the components responsible for unwanted changes in soil properties and (iv) analyse the mechanisms of association of OPWW OM with soil, the interplay between climatic conditions, pH, presence of multivalent cations and the resulting effects of land application. Laboratory incubation experiments, field experiments and new experiments to study heat-induced water repellency will be conducted to identify responsible OPWW compounds and mechanisms of interaction. Samples from field experiments and laboratory experiments are investigated using 3D excitation-emission fluorescence spectroscopy, thermogravimetry-differential thermal analysis-mass spectrometry (TGA-DSC-MS), LC-MS and GC-MS analyses. We will combine thermal decomposition profiles from OPWW and OPWW-treated soils in dependence of the incubation status using TGA-DSC-MS, contact angle measurements, sorption isotherms and the newly developed time dependent sessile drop method (TISED). The resulting process understanding will open a perspective for OPWW wastewater reuse in small-scale and family-scale olive oil production busi-nesses in the Mediterranean area and will further help to comprehend the until now not fully un-ravelled effects of wastewater irrigation on soil water repellency.

Dynamic (redox) interfaces in soil - Carbon turnover in microbial biomass and flux into soil organic matter

Existing models of soil organic matter (SOM) formation consider plant material as the main source of SOM. Recent results from nuclear magnetic resonance analyses of SOM and from own incubation studies, however, show that microbial residues also contribute to a large extent to SOM formation. Scanning electron microscopy showed that the soil mineral sur-faces are covered by numerous small patchy fragments (100 - 500 nm) deriving from microbial cell wall residues. We will study the formation and fate of these patchy fragments as continuously produced interfaces in artificial soil systems (quartz, montmorillonite, iron oxides, bacteria and carbon sources). We will quantify the relative contributions of different types of soil organisms to patchy fragment formation and elucidate the effect of redox con-ditions and iron mineralogy on the formation and turnover of patchy fragments. The develop-ment of patchy fragments during pedogenesis will be followed by studying soil samples from a chronosequence in the forefield of the retreating Damma glacier. We will characterize chemical and physical properties of the patchy fragments by nanothermal analysis and microscale condensation experiments in an environmental scanning electron microscope. The results will help understanding the processes at and characteristics of biogeochemical interfaces.

Release of hexavalent chromium from ore processing residues and the potential of biochar for chromium immobilization in polluted soils

Chromium (Cr) is introduced into the environment by several anthropogenic activities. A striking ex-ample is the area around Kanpur in the Indian state of Uttar Pradesh, where large amounts of Cr-containing wastes have been recently illegally deposited. Hexavalent Cr, a highly toxic and mobile contaminant, is present in significant amounts in these wastes, severely affecting the quality of sur-roundings soils, sediments, and ground waters. The first major goal of this study is to clarify the solid phase speciation of Cr in these wastes and to examine its leaching behavior. X-ray diffraction and synchrotron-based X-ray absorption spectroscopy techniques will be employed for quantitative solid phase speciation of Cr. Its leaching behavior will be studied in column experiments performed at un-saturated moisture conditions with flow interruptions simulating monsoon rain events. Combined with geochemical modeling, the results will allow the evaluation of the leaching potential and release kinetics of Cr from the waste materials. The second major goal is to investigate the spatial distribution, speciation, and solubility of Cr in the rooting zone of chromate-contaminated soils surrounding the landfills, and to study the suitability of biochar as novel soil amendment for mitigating the deleterious effects of chromate pollution. Detailed field samplings and laboratory soil incubation studies will be carried out with two agricultural soils and biochar from the Kanpur region.

Ökoeffizienz der Entsorgung in Bayern, Deutschland und der Schweiz

Im Auftrag des Bayerischen Landesamtes für Umwelt hat bifa den erstmals 2003 durchgeführten Ökoeffizienzvergleich der Entsorgungsstrukturen Bayerns, Deutschlands und der Schweiz erweitert und aktualisiert. Die Ergebnisse aus dem Jahr 2003 zeigten, dass der bayerische Weg zur Gestaltung der Abfallwirtschaft in seiner Ökoeffizienz im Vergleich mit den Entsorgungsstrukturen der Schweiz und dem deutschen Durchschnitt am besten abschnitt. Nach der, im Rahmen der aktuellen Beauftragung, durchgeführten Datenaktualisierung, der Bilanzierung zusätzlicher Wertstoffströme und der Berücksichtigung des Verbots der Ablagerung nicht vorbehandelter Abfälle rücken die Entsorgungsstrukturen hinsichtlich Ihrer Ökoeffizienz deutlich enger zusammen. Die Entsorgungsstruktur Bayerns weist im Vergleich zur Entsorgungsstruktur Deutschlands zwar noch ein geringfügig besseres ökologisches Gesamtergebnis auf, ist aber gleichzeitig mit leicht höheren Gesamtkosten verbunden. Die Entsorgungsstruktur der Schweiz ist etwas weniger ökoeffizient. Die Ursachen dafür sind eine geringere Umweltentlastung im ökologischen Gesamtergebnis, gepaart mit vergleichsweise hohen Entsorgungskosten. Methoden: Analyse und Moderation sozialer Prozesse, Ökobilanzierung und Systemanalyse, Ökonomie und Managementberatung.

Global assessment of vegetation photosynthesis and carbon assimilation through space measurements of chlorophyll fluorescence

The gross carbon uptake of terrestrial vegetation through photosynthesis is a crucial parameter in climate change research. A global, observation-based characterization of ecosystem gross primary production can only be performed with satellite measurements. However, the traditional description of vegetation from space is based on the so-called spectral vegetation indices, which are not able to provide a reliable indication of photosynthetic efficiency driving carbon assimilation by vegetation. This results in an inherent limitation of existing satellite products to provide an accurate description of ecosystem functioning. By contrast, ongoing developments in instrument design and modelling approaches have very recently made possible the retrieval of vegetation chlorophyll fluorescence from space measurements. A vast number of laboratory and field experiments have demonstrated that fluorescence is a direct proxy to vegetation light use efficiency which can therefore enable a much more accurate description of gross primary production. This project proposes the implementation of a research group with focus on the global monitoring and interpretation of chlorophyll fluorescence from existing and upcoming Earth Observation missions. This task will imply the development of a variety of atmospheric-surface radiative transfer modelling approaches, data processing, retrieval techniques and ecosystem modelling tools, with the ultimate objective of developing a new approach to the observation of carbon assimilation by vegetation from space.

Can the resistance and resilience of trees to drought be increased through thinning to adapt forests to climate change?

Recent and predicted increases in extremely dry and hot summers emphasise the need for silvicultural approaches to increase the drought tolerance of existing forests in the short-term, before adaptation through species changes may be possible. We aim to investigate whether resistance during droughts, as well as the recovery following drought events (resilience), can be increased by allocating more growing space to individual trees through thinning. Thinning increases access of promoted trees to soil stored water, as long as this is available. However, these trees may also be disadvantaged through a higher transpirational surface, or the increased neighbourhood competition by ground vegetation. To assess whether trees with different growing space differ in drought tolerance, tree discs and cores from thinning experiments of Pinus sylvestris and Pseudotsuga menziesii stands will be used to examine transpirational stress and growth reduction during previous droughts as well as their subsequent recovery. Dendroecology and stable isotopes of carbon and oxygen in tree-rings will be used to quantify how assimilation rate and stomatal conductance were altered through thinning. The results will provide crucial information for the development of short-term silvicultural adaptation strategies to adapt forest ecosystems to climate change. In addition, this study will improve our understanding of the relationship between resistance and resilience of trees in relation to extreme stress events.

Palaeo-Evo-Devo of Malacostraca - a key to the evolutionary history of 'higher' crustaceans

In my project I aim at a better understanding of the evolution of malacostracan crustaceans, which includes very different groups such as mantis shrimps, krill and lobsters. Previous studies on Malacostraca, on extant as well as on fossil representatives, focussed on adult morphology.In contrast to such approaches, I will apply a Palaeo-Evo-Devo approach to shed new light on the evolution of Malacostraca. Palaeo-Evo-Devo uses data of different developmental stages of fossil malacostracan crustaceans, such as larval and juvenile stages. With this approach I aim at bridging morphological gaps between the different diverse lineages of modern malacostracans by providing new insights into the character evolution in these lineages.An extensive number of larval and juvenile malacostracans is present in the fossil record, but which have only scarcely been studied. The backbone of this project will be on malacostracans from the Solnhofen Lithographic Limestones (ca. 150 million years old), which are especially well preserved and exhibit minute details. During previous studies, I developed new documentation methods for tiny fossils from these deposits, e.g., fluorescence composite microscopy, and also discovered the first fossil mantis shrimp larvae. For malcostracan groups that do not occur in Solnhofen, I will investigate fossils from other lagerstätten, e.g., Mazon Creek and Bear Gulch (USA), or Montceaules- Mines and La-Voulte-sur-Rhône (France). The main groups in focus are mantis shrimps and certain other shrimps (e.g., mysids, caridoids), as well as the bottom-living ten-footed crustaceans (reptantians). Examples for studied structures are leg details, including the feeding apparatus, but also eyes. The results will contribute to the reconstruction of 3D computer models.The data collected in this project will be used for evaluating the relationships within Malacostraca, but mainly for providing plausible evolutionary scenarios, how the modern malacostracan diversity evolved. With the Palaeo-Evo-Devo approach, I am also able to detect shifts in developmental timing, called heterochrony, which is interpreted as one of the major driving forces of evolution. Finally, the reconstructed evolutionary patterns can be compared between the different lineages for convergencies. These comparisons might help to explain the convergent adaptation to similar ecological niches in different malacostracan groups, e.g., life in the deep sea, life on the sea bottom, evolution of metamorphosis or of predatory larvae.As the project requires the investigation of a large number of specimens in different groups, I will assign distinct sub-projects to three doctoral researchers. The results of this project will not only be published in peer-reviewed journals, but will also be presented to the non-scientific public, e.g., during fossil fairs or museum exhibitions with 3D models engraved in glass blocks.

Forschergruppe (FOR) 986: Structural Change in Agriculture, How should Model Linkages be designed to analyze the Effects of Global Agricultural Trade Liberalization at the Farm Level?

In the last decades agricultural policy has gained increasingly in complexity. Nowadays it influences the food and agricultural sector from the global market down to the farm level. Widespread research questions, like the impact of the WTO negotiations on the farm structure, most often require comprehensive modeling frameworks. Thus, different types of models are utilized according to their comparative advantages and combined in a strategically useful way to more accurately represent micro and macro aspects of the food and agricultural sector. Consequently, in recent years we have seen an increase in the development and application of model linkages. Given this background, the overall objective of this subproject is a systematic sensitivity analysis of model linkages that gradually involves more and more characteristics of the linkage and the corresponding transfer of results between models. In addition, the project aims to answer the following specific question: How does structural change at the farm level influence aggregate supply and technical progress? Under which conditions is it possible to derive macro-relationships from micro-relationships? How does the aggregation level influence the model results and how can possible problems be overcome? This procedure is used to quantify the effects and to derive conditions for optimal interaction of the connected models. The analysis is based on the general equilibrium model GTAP (Global Trade Analysis Project) and the farm group model FARMIS (Farm Modelling Information System) which are employed in conjunction to analyze the effects of WTO negotiations on the farm level.

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