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Immobilisation of arsenic in paddy soil by iron(II)-oxidizing bacteria

Das Projekt "Immobilisation of arsenic in paddy soil by iron(II)-oxidizing bacteria" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Tübingen, Institut für Geowissenschaften, Zentrum für Angewandte Geowissenschaften.Arsenic-contaminated ground- and drinking water is a global environmental problem with about 1-2Prozent of the world's population being affected. The upper drinking water limit for arsenic (10 Micro g/l) recommended by the WHO is often exceeded, even in industrial nations in Europe and the USA. Chronic intake of arsenic causes severe health problems like skin diseases (e.g. blackfoot disease) and cancer. In addition to drinking water, seafood and rice are the main reservoirs for arsenic uptake. Arsenic is oftentimes of geogenic origin and in the environment it is mainly bound to iron(III) minerals. Iron(III)-reducing bacteria are able to dissolve these iron minerals and therefore release the arsenic to the environment. In turn, iron(II)-oxidizing bacteria have the potential to co-precipitate or sorb arsenic during iron(II)- oxidation at neutral pH followed by iron(III) mineral precipitation. This process may reduce arsenic concentrations in the environment drastically, lowering the potential risk for humans dramatically.The main goal of this study therefore is to quantify, identify and isolate anaerobic and aerobic Fe(II)-oxidizing microorganisms in arsenic-containing paddy soil. The co-precipitation and thus removal of arsenic by iron mineral producing bacteria will be determined in batch and microcosm experiments. Finally the influence of rhizosphere redox status on microbial Fe oxidation and arsenic uptake into rice plants will be evaluated in microcosm experiments. The long-term goal of this research is to better understand arsenic-co-precipitation and thus arsenic-immobilization by iron(II)-oxidizing bacteria in rice paddy soil. Potentially these results can lead to an improvement of living conditions in affected countries, e.g. in China or Bangladesh.

Rehabilitation of Degraded Forests in Yunnan (German-Chinese Cooperation for Agrarian Research)

Das Projekt "Rehabilitation of Degraded Forests in Yunnan (German-Chinese Cooperation for Agrarian Research)" wird/wurde gefördert durch: Bundesministerium für Verbraucherschutz, Ernährung und Landwirtschaft. Es wird/wurde ausgeführt durch: Universität Hamburg, Arbeitsbereich für Weltforstwirtschaft und Institut für Weltforstwirtschaft des Friedrich-Löffler-Institut, Bundesforschungsinstitut für Tiergesundheit.Background: An increasing frequency of massive flooding along the lower Yangtse River in China ended in a disastrous catastrophe in summer 1998 leaving several thousand people homeless, more than 3.600 dead and causing enormous economic damage. Inappropriate land-use techniques and large scale timber felling in the water catchment of the upper Yangtse and its feeder streams were stated to be the main causes. Immediate timber cutting bans were imposed and investigations on land use patterns were initiated by the Chinese Government. The Institute for World Forestry of the Federal Research Centre for Forestry and Forest Products was approached by the Yunnan Academy of Forestry in Kunming to exchange experiences and to cooperate scientifically in the design and application of appropriate afforestation and silvicultural management techniques in the water catchment area of the Yangtse. This cooperation was initiated in 1999 and is based on formal agreements in the fields of agrarian research between the German and Chinese Governments. Objectives: The cooperation was in the first step focussing on the identification of factors which caused the enormous floodings. After their identification measures of prevention were determined and put into practice. In this context experiences made in past centuries in the alpine region of central Europe served as an incentive and example for similar environmental problems and solutions under comparable conditions. Relevant key questions of the cooperation project were: - Analysis of forest related factors influencing the recent floodings of the Yangtse, - Analysis and evaluation of silvicultural management experiences from central Europe for know-how transfer, - Evaluation of rehabilitation measures for successful application in Yunnan, - Dissemination of knowledge through vocational training. Results: - Frequent wild grazing of husbandry is a key factor for forest degeneration beyond unsustainable timber harvests, forest fires and insect calamities leading to increased water run-off in the mountainous region of Yunnan; - Browsing of cattle interrupts succession thus avoiding natural regeneration and leaving a logging ban ineffective; - Mountain pasture in the Alps had similar effects in the past in central Europe. The introduction of controlled grazing has led to an ecologically compatible coexistence of pasture and ecology. Close-to-nature forestry can have positive effects in this sensitive environment. - Afforestation with site adopted broadleaves and coniferous tree species was implemented on demonstration level using advanced techniques in Yunnan.

Methodologies for dealing with uncertainties in landscape planning and related modeling; Uncertainty of predicted hydro-biogeochemical fluxes and trace gas emissions on the landscape scale under climate and land use change

Das Projekt "Methodologies for dealing with uncertainties in landscape planning and related modeling; Uncertainty of predicted hydro-biogeochemical fluxes and trace gas emissions on the landscape scale under climate and land use change" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Gießen, Institut für Landschaftsökologie und Ressourcenmanagement, Professur für Landschafts-, Wasser- und Stoffhaushalt.Water, carbon and nitrogen are key elements in all ecosystem turnover processes and they are related to a variety of environmental problems, including eutrophication, greenhouse gas emissions or carbon sequestration. An in-depth knowledge of the interaction of water, carbon and nitrogen on the landscape scale is required to improve land use and management while at the same time mitigating environmental impact. This is even more important under the light of future climate and land use changes.In the frame of the proposal 'Uncertainty of predicted hydro-biogeochemical fluxes and trace gas emissions on the landscape scale under climate and land use change' we advocate the development of fully coupled, process-oriented models that explicitly simulate the dynamic interaction of water, carbon and nitrogen turnover processes on the landscape scale. We will use the Catchment Modelling Framework CMF, a modular toolbox to implement and test hypothesis of hydrologic behaviour and couple this to the biogeochemical LandscapeDNDC model, a process-based dynamic model for the simulation of greenhouse gas emissions from soils and their associated turnover processes.Due to the intrinsic complexity of the models in use, the predictive uncertainty of the coupled models is unknown. This predictive (global) uncertainty is composed of stochastic and structural components. Stochastic uncertainty results from errors in parameter estimation, poorly known initial states of the model, mismatching boundary conditions or inaccuracies in model input and validation data. Structural uncertainty is related to the flawed or simplified description of natural processes in a model.The objective of this proposal is therefore to quantify the global uncertainty of the coupled hydro-biogeochemical models and investigate the uncertainty chain from parameter uncertainty over forcing data uncertainty up the structural model uncertainty be setting up different combinations of CMF and LandscapeDNDC. A comprehensive work program has been developed structured in 4 work packages, that consist of (1) model set up, calibration and uncertainty assessment on site scale followed by (2) an application and uncertainty assessment of the coupled model structures on regional scale, (3) global change scenario analyses and finally (4) evaluating model results in an ensemble fashion.Last but not least, a further motivation of this proposal is to provide project results in a manner that they support planning and decision taking under uncertainty, as this proposal is part of the package proposal on 'Methodologies for dealing with uncertainties in landscape planning and related modelling'.

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

Das Projekt "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" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau, Institut für Umweltwissenschaften.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.

Effect of diffusive/dispersive processes on stable isotope ratios of organic contaminants in aquifer systems

Das Projekt "Effect of diffusive/dispersive processes on stable isotope ratios of organic contaminants in aquifer systems" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Technical University of Denmark, Department of Environmental Engineering.Groundwater contamination by organic compounds represents a widespread environmental problem. The heterogeneity of geological formations and the complexity of physical and biogeochemical subsurface processes, often hamper a quantitative characterization of contaminated aquifers. Compound specific stable isotope analysis (CSIA) has emerged as a novel approach to investigate contaminant transformation and to relate contaminant sources to downgradient contamination. This method generally assumes that only (bio)chemical transformations are associated with isotope effects. However, recent studies have revealed isotope fractionation of organic contaminants by physical processes, therefore pointing to the need of further research to determine the influence of both transport and reactive processes on the observed overall isotope fractionation. While the effect of gasphase diffusion on isotope ratios has been studied in detail, possible effects of aqueous phase diffusion and dispersion have received little attention so far.The goals of this study are to quantify carbon (13C/12C) and, for chlorinated compounds, chlorine (37Cl/35Cl) isotope fractionation during diffusive/dispersive transport of organic contaminants in groundwater and to determine its consequences for source allocation and assessment of reactive processes using isotopes. The proposed research is based on the combination of high-resolution experimental studies, both at the laboratory (i.e. zero-, one- and two-dimensional systems) and at the field scales, and solute transport modeling. The project combines the expertise in the field of contaminant transport with the expertise on isotope methods in contaminant hydrogeology.

Microbial processes and iron-mineral formation in household sand filters used to remove arsenic from drinking water in Vietnam

Das Projekt "Microbial processes and iron-mineral formation in household sand filters used to remove arsenic from drinking water in Vietnam" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Tübingen, Zentrum für Angewandte Geowissenschaften (ZAG), Arbeitsgruppe Geomikrobiologie.Arsenic-contaminated ground- and drinking water is a global environmental problem with about 1-2Prozent of the worlds population being affected. The upper drinking water limit for arsenic (10 ìg/L) is often exceeded, especially in Asian countries, such as Vietnam. Household sand filters are already used as one very simple and cost-efficient treatment to remove arsenic from water. Oxidation of dissolved iron (Fe(II)) present in the groundwater leads to the formation of sparsely soluble iron(hydr)oxide particles (Fe(III)OOH) in the sand filter, which bind negatively charged arsenic species and reduce arsenic concentrations in the water. Arsenite (As(III); H3AsO3) binds generally less strong to metal oxides than arsenate (As(V); H2AsO4 -/HAsO4 2-), therefore As(V) is removed much more effectively than As(III). This is why As(III) oxidation to As(V) is of special interest for arsenic removal from drinking water. Whether and how the activity of iron- and arsenite-oxidizing bacteria contributes to effective arsenic removal in household sand filters is currently not known. One of the goals of this study therefore is to isolate, identify, and quantify Fe(II)- and As(III)-oxidizing microorganisms from filters and to study their iron and arsenic redox activities. Cultivation-based work will be complemented by molecular, cultivation-independent techniques to characterize and quantify the microbial communities in samples from different filter locations taken at various time points during filter operation (both at field sites and in artificial laboratory filter systems). The isolated iron- and arsenite-oxidizing bacteria will be studied with respect to their abilities to precipitate iron minerals (in the presence or absence of arsenic) and oxidize arsenite. Biogenic and abiogenic iron minerals formed by the isolated strains in the lab, on the sand filter material in Vietnam and in artificial laboratory filter systems will be identified and characterized, also with respect to arsenic sorption. And we will determine how biotic and abiotic processes that contribute to arsenic mobilization from arsenic-loaded iron mineral phases affect filter performance over time. The long-term goal of this research is to better understand the microbial redox transformation processes that drive arsenic/iron mineral interactions in natural and engineered systems, such as household sand filters and to give recommendations for improved filter use and filter material disposal.

Balancing regulating and provisioning ecosystem services: Comprehensive land-use concepts for effective conservation

Das Projekt "Balancing regulating and provisioning ecosystem services: Comprehensive land-use concepts for effective conservation" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Technische Universität München, Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung und Umwelt, Fachgebiet für Waldinventur und nachhaltige Nutzung.A growing trend to produce fuel ethanol from grain and continuing changes in human diets, as observed with increasing standard of living, have led to increasing land-use conflicts. The observable high food prices are - at least in part - a consequence of the above development. They act as signals to increase production, often combined with severe environmental problems. Moreover, as another obviously undesirable consequence, high prices may reduce consumption, particularly among the world's poor. Achieving sustainable land use by means of an optimal allocation of scarce land resources to competing purposes is thus a major global challenge for the 21st century. The results of this work are supposed to be transferred to the dry forest region around the Laipuna Reserve (Ecuador). We will couple several land-use models and modelling approaches, all built on economic drivers (economic risk and return of land-use options), to conceptualise a land-use model and to develop land-use scenarios for the study area at landscape level. The existing land-use approaches will be coupled for this task and expanded by dietary energy and fuel energy outputs and by consequences of land-use scenarios for carbon pools and water protection. The available models, such as 'Ecological-Economic Farm Diversification' (dynamic farm-level perspective), 'Optimized Land-Use Diversification' (comparative-static national level approach) and 'Compartmental land-use approaches' (dynamic farm/landscape-level, so far scenario based), address various scales. It is intended to combine them by means of modelling various farm types which are representative for a specific area. Land-use scenarios include various food price projections and scenarios on vulnerability of production systems. The hypothesis to be tested is: 'Increasing the production of food, biofuel and timber by appropriate landscape concepts for intensification and/or recultivation of abandoned lands reverses the adverse effects of indirect land-use change: Such strategies lead to more efficient land allocation and to decreasing prices, thus mitigating the pressure on forest ecosystems to reduce the costs of conservation strategies and those of providing regulating services.

Internationales Graduiertenkolleg (IRTG) 1070: Modellierung von Stoffflüssen und Produktionssystemen für eine nachhaltige Ressourcennutzung in intensiven Acker- und Gemüsebausystemen in der nordchinesischen Tiefebene' (769), SP 1.4 Evaluation of nutrient and pollutant cycles of livestock production systems and manure management systems in the North China Plain

Das Projekt "Internationales Graduiertenkolleg (IRTG) 1070: Modellierung von Stoffflüssen und Produktionssystemen für eine nachhaltige Ressourcennutzung in intensiven Acker- und Gemüsebausystemen in der nordchinesischen Tiefebene' (769), SP 1.4 Evaluation of nutrient and pollutant cycles of livestock production systems and manure management systems in the North China Plain" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft / Ministry of Education of the People's Republic of China. Es wird/wurde ausgeführt durch: Universität Hohenheim, Institut für Agrartechnik, Fachgebiet Verfahrenstechnik der Tierhaltungssysteme (440b).The increasing specialization and intensification of the agricultural food production in the North China Plain is leading to restrictions in nutrients and production cycles at farm and regional levels. As a result, livestock production in the North China Plain is entailing serious environmental negative impacts related to manure surpluses and recycling of nutrients, mainly leading to problems associated with water, soil and air pollution. On the other side higher nutrient demands in the local crops is leading to the purchase of chemical or mineral fertilizers when local or on-farm nutrients are not available. Therefore, the efficient use of organic fertilizers not only depends on their availability in the farms, but also on their nutritional composition. Likewise, soil nutrient requirements and plant physiological needs have to be taken into consideration. Indeed, the closer the nutrient cycles and the lower the environmental negative impacts and farm losses are, the greater the chances for a more sustainable resource use in the North China Plain. In the context of the IRTG, aspects of livestock farming in production systems in terms of widely closed nutrients cycles will be integrated. The material flows in different animal husbandry systems will be analysed and the environmental impacts dependent on livestock farming techniques, farms operability and their respective management will be investigated. The applicability and effectiveness of the technical and organizational measures for the reduction of material losses and, the environmental burdens caused by livestock and manure mismanagement in the North China Plain will be reviewed. The benefits and profits for the local cropping systems as result of the application of organic fertilizers originated from livestock farming will be both, ecologically and economically, evaluated as an alternative to replace the use of mineral fertilizers.

EMOCLIP - Institutional Partnership for Environmental Modeling and Climatology

Das Projekt "EMOCLIP - Institutional Partnership for Environmental Modeling and Climatology" wird/wurde gefördert durch: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung. Es wird/wurde ausgeführt durch: Universite de Geneve, Departement de Geographie.EMOCLIP: - institutional partnership project is devised to establish an institutional partnership between Institute for Environmental Sciences at the University of Geneva (ISE) and the Faculty of Applied Ecology Futura Singidunum University Belgrade (Futura). The project will be oriented toward strengthening Futura's institutional capacity on environmental modeling and climatology. Besides that, other positive effects, such as creating conditions for long term cooperation between ISE and Futura, improving coursesand teaching methods and creating a Centre for Environmental Modeling (CEM) at Futura will be realized. The realization of project will not only contribute to Futura's research capacities but will also have an impact on students' educational profiles. Students who complete studies, revised as a result of this project, will be much better prepared to deal with everyday environmental problems in practice through the application of environmental modeling. IP - climatology, CL - environmental modeling, EMO The comprehensive and sustainable management structure, preparation and realization of training courses for young researchers, organization of dissemination workshops and seminars for students and other stakeholders, improvement of Futura's research infrastructure to conduct environmental modeling, improvement of teaching methods and courses syllabuses. including the formation of IP will be carried outTo achieve these objectives a series of activities Jointly established overall objectives of this IP can be presented as follows: shared responsibilities for strengthening institutional research capacities in the area of environmental modeling and climatology; participative strategic planning for institutional structural development and modernization of research and teaching methods for environmental modeling and climatology; joint research management structure development and improvement; improvement of efficiency, transparency and visibility of jointly research activities; capacity building of Futura research staff for international standards regarding environmental modeling and similar subjects; development of curricula for environmental modeling and climatology master or PhD courses; networking improvement between Swiss and Eastern European research institutions with the aim of knowledge transfer and information dissemination for environmental modeling and climatology.

Sources, sinks and impacts of atmospheric nitrogen deposition in the Arctic (NSINK), WP5: Aquatic Ecosystems and Palaeolimnology

Das Projekt "Sources, sinks and impacts of atmospheric nitrogen deposition in the Arctic (NSINK), WP5: Aquatic Ecosystems and Palaeolimnology" wird/wurde gefördert durch: Kommission der Europäischen Gemeinschaften Brüssel. Es wird/wurde ausgeführt durch: Universität Innsbruck, Institut für Ökologie.The NSINK Initial Stage Network training network targets one of the most vital, interdisciplinary problems facing future Arctic environmental management: namely the enrichment of Arctic terrestrial and aquatic ecosystems by reactive atmospheric nitrogen from low latitude emission centres. This problem will greatly exacerbate ecosystem response to climate change, and urgently requires holistic, sources to sinks type studies of nitrogen dynamics. The delivery of nitrogen from tropospheric and even stratospheric sources will be considered using lagrangian and eulerian approaches that directly link air mass movements to the mass balance of nitrogen at the ground surface. NSINK will then track the fate of this nitrogen through the polar sunrise and into the melt period by considering atmosphere-snow-soil-organism transfers at small plot to catchment scales. Further, in order to constrain temporal change in nitrogen accumulation in this sensitive environment, research into the collection and interpretation of ice core and lake sediment archives will also be undertaken and linked to a reanalysis of atmospheric observations collected over the last 16 years at Ny Ålesund. The concept behind NSINK is that a major European research facility (namely Ny Ålesund in Svalbard) can be used to train a significant cohort of new expertise in environmental science to tackle a major environmental problem from a multidisciplinary perspective. NSINK therefore offers training in atmospheric sciences, snow physics, hydrology, biogeochemistry and aquatic/terrestrial ecology from experienced practitioners in UK , Norwegian, Swedish, Austrian and German institutions. The principal scientific objectives of NSINK are to: 1. Establish the climatology and dynamics of atmospheric nitrogen delivery to the European High Arctic at an unprecedented range of temporal scales; 2. Construct mass balance models of the biogeochemical cycling of reactive nitrogen in the resident snow, ice and ecosystem stores within this part of the European High Arctic; 3. Conduct process studies of nitrogen dynamics that include the use of natural and artificial tracers (where relevant) of the fluxes that link the above stores; 4. Determine ecosystem response to enhanced atmospheric N deposition, and consequences for ecosystem biodiversity, productivity and carbon balance; 5. Produce models with the capacity to forecast ecosystem response to scenarios of coupled climate warming and atmospheric nitrogen enrichment. Fellow 5A ( Nitrogen Cycling in Aquatic Ecosystems ) will consider microbial foodwebs and nitrogen cycling in the aquatic ecosystems of the Ny Ålesund area whilst under the supervision of Birgit Sattler and Roland Psenner. Fellow 5B ( Palaeolimnology ) will work on the palaeolimnology of local lakes in Svalbard under the supervision of Karin Koinig (second supervisor: Anne Hormes). This work will constrain the history and drivers of physico-chemical conditions throughout the late Holocene by exa

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