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.
Das Projekt "Release of hexavalent chromium from ore processing residues and the potential of biochar for chromium immobilization in polluted soils" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Köln, Fachgruppe Geowissenschaften, Geographisches Institut.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.
Das Projekt "Emmy Noether-Nachwuchsgruppen, Development and risk assessment of transgenic environmentally-friendly insect pest control methods for fruit flies and mosquitoes" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Gießen, Institut für Phytopathologie und Angewandte Zoologie, Abteilung Angewandte Entomologie.Various species of pest insects cause substantial damage to agriculture every year, or transmit deadly diseases to animals and humans. A successful strategy to control pest insect populations is based on the Sterile Insect Technique (SIT), which uses the release of mass-reared, radiation sterilized male insects to cause infertile matings and thus reduce the pest population level. However, irradiation is not applicable to every insect species. Thus, new strategies based on genetic modifications of pest insects have been developed or are currently under investigation.The goal of the proposed research is to improve the development and ecological safety of genetically engineered (GE) insects created for enhanced biological control programs, including the SIT and new strategies based on conditional lethality. A major concern for GE insect release programs is transgene stability, and maintenance of their consistent expression. Transgene loss or intra-genomic movement could result in loss of strain attributes, and may ultimately lead to interspecies movement resulting in ecological risks. To address potential transgene instability, a new transposon vector that allows post-integration immobilization will be tested in the Mediterranean, Mexican and Oriental fruit fly tephritid pest species. In addition, the system will be established in the mosquito species Aedes and Anopheles - carriers of dengue and malaria.Random genomic insertion is also problematic for GE strain development due to genomic position effects that suppress transgene expression, and insertional mutations that negatively affect host fitness and viability. Diminished transgene expression could result in the unintended survival of conditional lethal individuals, or the inability to identify them. To target transgene vectors to defined genomic insertion sites having minimal negative effects on gene expression and host fitness, a recombinase-mediated cassette exchange (RMCE) strategy will be developed that. RMCE will also allow for stabilization of the target site, will be tested in tephritid and mosquito species, and will aid to the development of stabilized target-site strains for conditional lethal biocontrol. This will include a molecular and organismal evaluation of an RNAi-based lethality approach. Lethality based on an RNAi mechanism in the proposed insects would increase the species specificity and having multiple targets for lethality versus one target in existing systems. By seeking to improve transgene expressivity and stabilization of transposon-based vector systems, this proposal specifically addresses issues related to new GE insects by reducing their unintended spread after field release, and by limiting the possibilities for transgene introgression.
Das Projekt "Schwerpunktprogramm (SPP) 1685: Ecosystem nutrition: forest strategies for limited phosphorus resources; Ökosystemernährung: Forststrategien zum Umgang mit limitierten Phosphor-Ressourcen, Microbial P mobilization and immobilization in the rhizosphere and root-free soil (SPP: P Nutrition & recycling)" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Bayreuth, Fachgruppe Geowissenschaften, Bayreuther Zentrum für Ökologie und Umweltforschung (BayCEER), Lehrstuhl für Bodenökologie.Soil microorganisms can mobilize and immobilize phosphorus (P), and therefore strongly affect the availability of P to plants. In this project we hypothesize that the ratio of labile P to microbial P increases during the transition from acquiring to recycling ecosystems. Microbial and plant P uptake will be studied with 33P that will be quantified in microbial and plant biomass as well as in lipids. To what extent microorganisms immobilize and mobilize P during decomposition of soil organic matter will be explored with a 14C/33P labeled monoester. Seasonal dynamics of actual and potential P mineralization (33P dilution and phosphatase activity), and microbial P immobilization will be studied with soils of the transition from acquiring to recycling ecosystems. The contribution of litter-derived P will be explored in a litter exclusion experiment in the field. Spatial patterns of microbial and plant P mineralization in the rhizosphere will be explored by analyses of areas of high acid and alkaline (=microbial-derived) phosphatase activity by soil zymography, and their relations with areas of high rhizodeposition (14C imaging). In conclusion, we will analyse mechanisms of actual and potential microbial P mineralization and immobilization, localization, and consequences for P uptake by plants.
Das Projekt "AsFeP0 - A model concept for in situ investigation or arsenic and phosphate adsorption to predefined iron minerals and to characterize transformation processes of iron minerals" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Eidgenössische Anstalt für Wasserversorgung, Abwasserreinigung und Gewässerschutz, Abteilung Wasserressourcen und Trinkwasser.Shallow groundwater of the huge deltaic systems of Asia like the Red River Delta in Vietnam is often enriched in inorganic arsenic (As), threatening the health of millions of residents. The massive abstraction of groundwater in these areas locally causes an irreversible mixing of arsenic-free groundwater resources with arsenic-rich groundwater. Increased concentrations of competitive anions, especially phosphate (PO43-), decrease the immobilization capacity of the sediments. During transport, the mobility of dissolved As in local aquifers is strongly influenced by adsorption to sedimentary and ubiquitously occurring iron(oxyhydr)oxides. Additionally, arsenic-rich groundwater is often enriched in reduced iron (Fe2+) as well, which is capable to react with iron(oxyhydr)oxides, thereby inducing mineral transformations. Such transformations permanently affect the arsenic adsorption and immobilization capacity of the sediments.Within the scope of this research project, the underlying mechanisms related to As transport and the resulting threat to arsenic-free groundwater resources will be characterized in cooperation with the Swiss Federal Institute of Aquatic Science and Technology (Eawag). The research concept aims at assessing the complex interactions within the arsenic-iron-phosphate-system under field conditions at a study site next to the Red River. First, filtration experiments using local groundwater enriched in As and PO43- will be used to determine the As adsorption capacity of different and previously geochemically characterized iron(oxyhydr)oxides. In a second step, sample carrier containing As loaded iron(oxyhydr)oxides will be introduced into surface near aquifer parts of the study site (via existing groundwater monitoring wells). These samples will be exposed to local groundwater characterized by increased As, Fe2+ and PO43- concentrations for the following nine months. Using the in situ exposition of predefined iron(oxyhydr)oxides, it will be possible to distinguish potential mineral transformations and their influences on the As immobilization capacity of the respective iron(oxyhydr)oxides. By combining the results and outcomes of the field experiments, new and important conclusions regarding the mobility of As can be drawn. The data can be used to create a hydrochemical transport model describing reactive As transport within the investigation area. In addition, the results of the in situ exposition experiments will allow to draw conclusions in respective to the long term As immobilization capacity of different iron(oxyhydr)oxides, which is an essential information regarding in situ decontamination techniques.
Das Projekt "Stickstoff-Immobilisierung - Regionalisierung von Eingangsdaten der Critical-Load-Berechnung" wird/wurde gefördert durch: Umweltbundesamt. Es wird/wurde ausgeführt durch: Johann Heinrich von Thünen-Institut Bundesforschungsinstitut für Ländliche Räume, Wald und Fischerei - Institut für Waldökosysteme.Ziel der vorliegenden Studie ist es, für Deutschland flächendeckend Stickstoffimmobilisierungsraten für die Critical-Load-Berechnung abzuleiten. Es soll dabei geprüft werden, inwieweit die landnutzungs spezifische Bodenübersichtskarte Deutschland 1/1.000.000 (BÜK1000N v2.3) sowohl als Karten- wie auch als Datengrundlage genutzt werden kann. Aufbauend auf dem Vorgängerprojekt (Projektnr. 76011) werden die Stickstoffimmobilisierungsraten anhand rezent gemessenen Stickstoffvorräte und dem dazugehörigen Bodenalter abgeleitet. Die Eignung der BÜK1000N als Datengrundlage wird dabei aufgrund der Datenlage zu den Stickstoffvorräten als unzureichend eingeschätzt. Die Nutzung der Daten der zweiten Bodenzustandserhebung im Wald (BZE II) wird favorisiert. An den BZE-Punkten können Stickstoffvorräte der organischen Auflage und des Mineralbodens bis zu einer Tiefe von 90 cm berechnet werden. Das Bodenalter der BZE-Punkte wird entsprechend dem Vorgehen des Vorgängerprojektes anhand der maximalen Vereisung während der letzten Eiszeit festgelegt. Die Stickstoffvorräte der BZE-Aufnahmepunkte werden den BÜK1000N-Einheiten und Corine Landnutzungsklassen zugeordnet. Es zeigt sich, dass sich die Stickstoffimmobilisierungsraten anhand der BÜK1000N-Einheiten in drei Klassen gruppieren lassen. Die höchsten Immobilisierungsraten finden sich in den organischen Böden der BÜK1000N-Einheiten 6 und 7 mit 1,37 Ì 0,29 kg ha-1 a-1, mittlere Raten in Höhe von 0,93 Ì 0.06 kg ha-1 a-1 in den BÜK1000-Einheiten 19 ââ‚ Ì 21 mit mittel- bis tiefgründige Böden vorwiegend aus Geschiebelehm oder ââ‚ Ìmergel sowie Böden im montanen und subalpinen Bereich des Alpenraums. In den übrigen BÜK1000N-Einheiten weisen die Böden Raten von 0,31 Ì 0,04 kg ha-1 a-1 auf. Innerhalb der einzelnen BÜK1000N-Einheiten zeigen sich kaum Unterschiede zwischen den Waldtypen der Corine Landnutzungsdaten, so dass empfohlen wird, die Stratifizierung der Immobilisierungsraten anhand der BÜK1000N-Einheiten vorzunehmen. Mit dem vorliegenden Regionalisierungsansatz können 98,8 % der Rezeptorflächen der Critical-Load-Berechnung abgedeckt werden.
Das Projekt "Depletion of algal toxin-contaminated water using selective biofilters based on plant-produced antibodies (plantibodies)" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Technische Universität München, Institut für Wasserchemie und Chemische Balneologie, Lehrstuhl für Analytische Chemie und Wasserchemie.Although the use of genetically modified plants for bioremediation, or the in situ cleaning of contaminated sites, has been known for quite some time, little attention has so far been paid to the production of antibodies in plants and their ex vivo application in selective depletion. Therefore, highly affine and specific antibodies against algal toxins using microcystin as an example will be produced in plants at low cost within this research project. The basis is a monoclonal antibody (Mab 10E7, species: mouse) generated in a former research project. The sequence of the variable domains will be determined, optimized for plants and sub cloned into suitable plant transformation vectors, which already contain constant antibody sequences. In addition, a scFv fragment containing different tag sequences and fusion proteins will be constructed. Leaf-based (tobacco) as well as seed-based (barley) systems will be used.Affinity-purified plant-produced antibodies (plantibodies) will be characterized in detail for their binding properties using microtitre plate-ELISA and surface plasmon resonance (SPR). The monoclonal mouse antibody will be used as reference. To assure cost-efficiency for future applications, roughly purified fractions (sequential pH and temperature treatment followed by filtration) will be tested for the upscaling. Following immobilization of the plantibody fractions on suitable substrates, for instance membranes, porous polymer monoliths or in porous glasses, their application for depletion will be defined using model water samples spiked fortified with microcystins.
Das Projekt "Optimized esterase biocatalysts for cost-effective industrial production (OPTIBIOCAT)" wird/wurde gefördert durch: Kommission der Europäischen Gemeinschaften Brüssel. Es wird/wurde ausgeführt durch: Universita di Napoli Federico II.OPTIBIOCAT is a 48 months project aimed at developing biocatalysts based on feruloyl esterases (FAEs) and glucuronoyl esterases (GEs) for production of phenolic fatty- and sugar- esters with antioxidant activity for cosmetic industry, expanding the number/type of industrial biotransformations. Selected FAEs and GEs available within the consortium will be improved for their thermo- and solvent- resistance and substrate specificity by site-directed mutagenesis and directed evolution. Novel enzymes will be discovered by mining for new genes from available genomes. An inventory of novel FAEs and GEs will be developed including 50 fungal and 500 bacterial esterases, 25 site-directed and 20 directed evolved mutants. Enzymatic performances will be optimized to enhance the yield (up to the theoretical yield of 100%) and productivity (up to 0.5-1 g/l/h) of reactions giving the main targeted antioxidants: butyl ferulate, p-coumarate, caffeate, sinapate and 5-O-(trans-feruloyl)-arabinofuranose (using FAEs), glucuronate and benzyl glucuronate (using GEs). FAEs and GEs will be also tested for production of other compounds with improved biological activity and properties of hydrophilicity/hydrophobicity for cosmetic applications. Cost-effective methods will be developed for production of the new biocatalysts, in the g/L scale, and for their technical application to produce antioxidants for cosmetic industry, up to 20L. Enzyme immobilization will increase their recyclability up to ten cycles. The ability of the developed catalysts to work in conditions miming the industrial ones with reduced use of solvents and lower temperature than the chemical routes will be demonstrated. The techno-economic viability and environmental friendliness will be assessed considering a full industrial scale scenario. OPTIBIOCAT involves a highly skilled and multidisciplinary partnership of 16 partners from 8 EU countries, and it is a strongly industry driven project through the participation of 8 SMEs and 1 large company.
Das Projekt "Bioverfuegbarkeit gebundener Triazin - Rueckstaende in Boden" wird/wurde gefördert durch: Novartis Crop Protection. Es wird/wurde ausgeführt durch: Technische Hochschule Aachen, Fachbereich 01 Mathematisch-Naturwissenschaftliche Fakultät, Lehrstuhl Biologie V - Umweltanalytik.Triazin Herbizide bilden in Boden zT betraechtliche Mengen gebundener Rueckstaende, deren Bioverfuegbarkeit im Vergleich zum freien Wirkstoff reduziert ist. Im Projekt soll die Bioverfuegbarkeit 14C-markierter Simazinrueckstaende in toto bzw nach Fraktionierung in bindende Huminfraktionen in verschiedenen Pflanzenspezies sowie in Pflanzenzellkulturen untersucht werden. Ausserdem wird untersucht, inwieweit die Rueckstaende durch die Rhizosphaerenaktivitaet und durch sie gebildetes loesliches organisches Material remobilisiert bzw wieder bioverfuegbar wird.
Das Projekt "Untersuchung des Umweltverhaltens und der numerischen Simulationsmoeglichkeiten des Schadstofftransports sprengstofftypischer Verbindungen im Umfeld von Ruestungsaltlasten" wird/wurde gefördert durch: Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie / Sächsisches Landesamt für Umwelt, Landwirtschaft und Geologie. Es wird/wurde ausgeführt durch: DGFZ Dresdner Grundwasserforschungszentrum e.V..Das Vorhaben ist auf die Ermittlung von Verfahren und Methoden zur Parameterermittlung fuer die Modellierung des Schadstofftransports sprengstofftypischer Verbindungen (STV) gerichtet. Im Mittelpunkt der Untersuchungen standen Sorptions-, Transformations- und Remobilisierungsprozesse von Nitroaromaten im Grundwasserleiter. Die Sorption der Nitroaromaten wird stark vom Gehalt an schichtsilikatischen Komponenten im Sediment beeinflusst. Dabei ist das Sorptionsgleichgewicht von Nitroaromaten in Sedimenten des Grundwasserleiters stark konzentrationsabhaengig. Fuer Nitroaromatenkonzentrationen im Porenwasser groesser als 0,2 mg/l beschreibt das nichtlineare Langmuir-Freundlich-Modell die Stoffspeicherung. Weiterhin wurde im Mehrkomponentensystem konkurrierendes und kooperatives Sorptionsverhalten einiger Nitroaromaten festgestellt. Die Untersuchungen zur Transformation der Nitroaromaten zeigten, dass native Mikroorganismen in der Lage sind, Nitroaromaten zu reduzieren. In Langzeitversuchen mit natuerlichem, hochkontaminierten Grundwasser zeigte sich, dass vor allem Trinitrotoluol (TNT) zu den entsprechenden Monoaminoverbindungen reduziert wird. In Versuchen zur Ermittlung der Remobilisierung der Nitroaromaten wurden Auswaschgrade in Fein- und Mittelsanden zu 0,5 bzw. 6,8 Prozent bestimmt. Die Infiltration von Kalziumchlorid bewirkte eine Erhoehung (fuer 4-NT um 38 Prozent) der Remobilisierung der Nitroaromaten. Aus den Prozessuntersuchungen sind Kennwerte ableitbar, die als wichtige Entscheidungskriterien in den Verfahrensablauf der Altlastenbehandlung einfliessen, bzw. innerhalb der Prognostik zur Stoffausbreitung und der Vorbereitung zur Gefahrenabwehr verankert werden koennen.
| Origin | Count |
|---|---|
| Bund | 24 |
| Land | 2 |
| Type | Count |
|---|---|
| Förderprogramm | 24 |
| License | Count |
|---|---|
| offen | 24 |
| Language | Count |
|---|---|
| Deutsch | 14 |
| Englisch | 11 |
| Resource type | Count |
|---|---|
| Keine | 19 |
| Webseite | 5 |
| Topic | Count |
|---|---|
| Boden | 21 |
| Lebewesen & Lebensräume | 23 |
| Luft | 16 |
| Mensch & Umwelt | 24 |
| Wasser | 20 |
| Weitere | 24 |
