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Effect of weed management strategies on the risk of enteric pathogen transfer into the food chain and lettuce yield and quality

Das Projekt "Effect of weed management strategies on the risk of enteric pathogen transfer into the food chain and lettuce yield and quality" wird vom Umweltbundesamt gefördert und von Universität Bonn, Institut für Organischen Landbau durchgeführt. The risk of pathogen transfer from soil to plant, here: lactuca sativa var. capitata, under organic farming conditions is to be investigated within the scope of the QLIF project. When brute fertilisers are applied during production, a health risk by consuming raw eadibles, as e.g. lettuce, is often discussed because of the demanding high standard of sanitation. The type of fertiliser might promote transfer of Enterobacteriaceae, and among these possibly human pathogens. Splash-effects during rainfall and irrigation as well as transfer of soil particles during mechanical weed control. Risks of the pathogen transfer into lettuce will be examined by use of different fertilisation and weed control management strategies, the latter being compared regarding their effectiveness in reducing pathogen transfer. Different field trials with organic fertilisation will be performed in 2006 and 2007. The contents of Enterobacteriaceae, coliforms and E. coli are used as sanitation indicators for the assessment of the effectivity of weed control strategies. Therefore, the contents will be measured in soil as well as in plants. Furthermore, the quality of lettuce will be acquired by analyses of nutrient composition and morphological measurements.

B 4.1: Land vulnerability and land suitability analysis in Northern Vietnam

Das Projekt "B 4.1: Land vulnerability and land suitability analysis in Northern Vietnam" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Bodenkunde und Standortslehre durchgeführt. As populations are steadily increasing in VN, farming land becomes scarce and new areas are opened up for cultivation, mainly in mountainous regions. On the fragile steep slopes deforestation and soil erosion are the well-known consequences. Land use in Yen Chau District, the study area in Son La, has significantly changed in the last decades. Until now, mainly soil degradation is reported on upland fields, but also soil erosion is increasing, both decreasing crop yields. In this project a database for topography, land use and soil properties within two subcatchments in Yen Chau will be created. The main goal of the project will be to carry out land suitability analysis and land vulnerability analysis, based on the data stored in the database, to provide tools for future sustainable land use planning. For this, a broad approach is intended by assessing land suitability for various crops, fruit trees and livestock production as well as to work out land vulnerability of the research area based on soil characteristics and topographic situation. The land suitability and vulnerability analysis will be carried out with the adopted SOTER (Soil and Terrain) approach. Normally used for a 1:500000 scale the SOTER technology will be developed for a 1:50.000 scale for two subcatchments. This is especially necessary because the closely cooperating projects C4.1 (Land use modelling), B5.1 (Water quality analysis) and G1.2 (Sustainability strategies) will rely on the spatial data of this scale. A totally new objective will be attempted by breaking down the SOTER technology to a scale of 1:5.000 for a village area in one of the selected subcatchments to regard the typical small-scale land use mosaic of a village area. Only with this scale the typical small scale land use mosaic of a village area can relatively precisely be mapped taking settlement areas, fish ponds, homegardens, fields, pastures, forests and scrubland as well as streams and creeks into account. With this approach it will be the first time possible to evaluate agricultural production on a village level using the SOTER technology. The SOTER database will be used with algorithms and soil transfer functions in order to derive soil suitability and soil vulnerability of certain areas. For the suitability analysis of different crops mainly the static approach for water regime, nutrient regime and potential root zone will be generated. As an important tool for decision making the erosion hazards due to water and especially gravity has to be visualized. As participatory soil mapping provides valuable additional information for land use evaluation and potential planning, this approach will be integrated on both the subcatchment and the village level in joint cooperation with A1.3 (Participatory Research). Finally, land use scenarios regarding different factors, e.g. change of cropping patterns, introduction of fruit trees, intensification of fish production or changes in market access, will be modelled.

Litter decomposition in mixed spruce-beech stands

Das Projekt "Litter decomposition in mixed spruce-beech stands" wird vom Umweltbundesamt gefördert und von Universität Freiburg, Waldbau-Institut durchgeführt. It is the declared aim of many state forest agencies to convert monocultures of Norway spruce (Picea abies), which are wide-spread in central Europe, to mixed stands of spruce and broadleaved trees, which in most cases would be European beech (Fagus sylvatica). Mixed species stands of these species may have a higher degree of ecological stability because they are less susceptible to windthrow and because nutrient cycling is tighter than in pure stands of spruce. Needle litter of Norway spruce is often less decomposable as that of the original forest, which was replaced by the plantations. As a result the forest floor layer tends to accumulate in many spruce monocultures. The build-up of the forest floor to humus forms such as moder and raw humus represents unfavourable biological soil conditions and a partial discoupling of the nutrient cycling. Additional consequences of this process may be soil acidification and podzolisation in pure spruce stands, which may further destabilise ecosystem processes. Introduction of beech, which can provide leaf litter of greater decomposability may reverse these processes and lead to more favourable humus forms that represent greater biological activity. However, it has been shown that the admixture of beech to spruce effectively leads to a reduced forest floor layer only for some soil types. This points to the importance of identifying the soil types and stand conditions for which the introduction of beech into spruce forest can lead to a significant improvement of the humus form and thus nutrient cycling. The proposed work will contribute to this by identifying sites, where admixture of F. sylvatica to P. abies stands will improve litter decomposition and thus the humus form. Specifically the research will examine how a range of environmental and litter quality factors influence the decomposition of beech and spruce litter, how litter quality is influenced by site quality, and what proportions of beech litter of a certain quality may be required to improve spruce needle decomposition.

Untersuchungen zur Erfassung des Cd-Carry-over-Effekts bei Schlachtschweinen

Das Projekt "Untersuchungen zur Erfassung des Cd-Carry-over-Effekts bei Schlachtschweinen" wird vom Umweltbundesamt gefördert und von Universität München, Institut für Hygiene und Technologie der Lebensmittel tierischen Ursprungs durchgeführt. Das Vorhaben dient der Feststellung des Cd-Carry-over von Futter auf Fleisch, Lebern und Nieren von Schlachtschweinen. Die Cd-Bestimmungen erfolgen nach nasser Mineralisation des Untersuchungsmaterials (Futter, Fleisch, Leber, Nieren) flammenlos atomabsorptionsspektrometrisch.

Forest management in the Earth system

Das Projekt "Forest management in the Earth system" wird vom Umweltbundesamt gefördert und von Max-Planck-Institut für Meteorologie durchgeführt. The majority of the worlds forests has undergone some form of management, such as clear-cut or thinning. This management has direct relevance for global climate: Studies estimate that forest management emissions add a third to those from deforestation, while enhanced productivity in managed forests increases the capacity of the terrestrial biosphere to act as a sink for carbon dioxide emissions. However, uncertainties in the assessment of these fluxes are large. Moreover, forests influence climate also by altering the energy and water balance of the land surface. In many regions of historical deforestation, such biogeophysical effects have substantially counteracted warming due to carbon dioxide emissions. However, the effect of management on biogeophysical effects is largely unknown beyond local case studies. While the effects of climate on forest productivity is well established in forestry models, the effects of forest management on climate is less understood. Closing this feedback cycle is crucial to understand the driving forces behind past climate changes to be able to predict future climate responses and thus the required effort to adapt to it or avert it. To investigate the role of forest management in the climate system I propose to integrate a forest management module into a comprehensive Earth system model. The resulting model will be able to simultaneously address both directions of the interactions between climate and the managed land surface. My proposed work includes model development and implementation for key forest management processes, determining the growth and stock of living biomass, soil carbon cycle, and biophysical land surface properties. With this unique tool I will be able to improve estimates of terrestrial carbon source and sink terms and to assess the susceptibility of past and future climate to combined carbon cycle and biophysical effects of forest management. Furthermore, representing feedbacks between forest management and climate in a global climate model could advance efforts to combat climate change. Changes in forest management are inevitable to adapt to future climate change. In this process, is it possible to identify win-win strategies for which local management changes do not only help adaptation, but at the same time mitigate global warming by presenting favorable effects on climate? The proposed work opens a range of long-term research paths, with the aim of strengthening the climate perspective in the economic considerations of forest management and helping to improve local decisionmaking with respect to adaptation and mitigation.

SOLEIL: Solar variability and trend effects in layers and trace gasesin the upper atmosphere

Das Projekt "SOLEIL: Solar variability and trend effects in layers and trace gasesin the upper atmosphere" wird vom Umweltbundesamt gefördert und von Leibniz-Institut für Atmosphärenphysik e.V. an der Universität Rostock durchgeführt. In der wissenschaftlichen Klimadiskussion steht der Einfluss des Anstiegs anthropogener Treibhausgase auf die globale Änderung unserer Atmosphäre in den untersten Kilometern im Vordergrund. Allerdings ist die bisher eingetretene mittlere globale Temperaturerhöhung mit 0.85 K von 1880 bis 2012, dies entspricht 0.06 K pro Dekade, jedoch klein. In der Atmosphäre oberhalb von etwa 8 km kehrt sich das Vorzeichen des Treibhauseffekts um: ein Anstieg der Konzentration von infrarot-aktiven Gasen führt zu einer Abkühlung durch eine gesteigerte Emission von Strahlung in den Weltraum. Die globale Veränderung der Atmosphäre findet besonders stark in einem Höhenbereich von 50-75 km statt. Antworten auf die Fragen nach den Ursachen für diese rapiden Änderungen in der mittleren Atmosphäre können uns nur numerische Atmosphärenmodelle (z.B. LIMA) geben. Letztere zeigen, dass die Strahlungsbilanz der mittleren Atmosphäre weitgehend bestimmt wird durch die Spurengase CO2 und O3. Die multivariate Trendanalyse erlaubt nun eine Aussage über den Beitrag am Gesamttrend der einzelnen Spurengase O3 und CO2. Die Spurengase CO2 und O3 tragen jeweils 2/3 bzw. 1/3 zum Trend bei. Die größten Trends liegen im Drucksystem mit 1.3 K/Dekade bei ca. 60 km, während auf geometrischen Höhen der Kontraktionseffekt der Atmosphäre die maximalen Trends auf bis zu 1.8 K/Dekade bei 70 km verstärkt. In den Höhen 80-90 km sind die Trendwerte am kleinsten und können sogar das Vorzeichen wechseln. Dieses Verhalten ist bedingt durch die sehr niedrigen Absoluttemperaturen in 80-90 km Höhe, die sehr empfindlich auf Variationen in den Strahlungsflüssen aus der Stratopausenregion reagieren. Weiterhin konnte in 'SOLEIL' gezeigt werden, dass Temperaturtrends zeitlich variabel sind. So zeigen im Teilzeitraum 1980-1996 die Temperaturen ihren stärksten Abfall aufgrund der Ozonabnahme: die Temperaturtrends können Werte bis zu 4 K pro Dekade erreichen. Im Zeitraum 1995-2009 sind die Durchschnittstemperaturen nahezu unverändert, weil sich hier das stratosphärische Ozon wieder aufbaut ('ozone recovery'). Diese Phasen starker und schwacher Abkühlung zwischen 1961 bis 2008 sind konsistent mit abgeleiteten Temperaturtrends aus französischen Lidarbeobachtungen und Phasenhöhenmessungen am Institut für Atmosphärenphysik (IAP) Kühlungsborn. Der Höhenbereich 80-90 km ist auch die Region, in der Eiswolken seit mehr als 100 Jahren beobachtet werden. Diese Eiswolken (NLC/PMC) existieren in der Sommermesopausenregion polwärts ab 50°N und können sich nur unter sehr kalten Temperaturen unterhalb von etwa 150 K ausbilden. Obwohl der Wasserdampfgehalt in der Mesopausenregion mit 1-7 ppmv sehr gering ausfällt, ist diese Feuchtekonzentration ausreichend für die Bildung von Eisteilchen. Die Nukleation und das Wachstum dieser Eispartikel reagiert sehr empfindlich auf Änderungen der Temperatur und des Wasserdampfes. Aus diesem Grund werden NLC/PMC auf ihre Rolle als potentieller Indikator für Klimaänderungen der globalen Atmosph

Plant-soil interactions in changing rice cropping systems and their influence on C and N dynamics

Das Projekt "Plant-soil interactions in changing rice cropping systems and their influence on C and N dynamics" wird vom Umweltbundesamt gefördert und von Universität Bonn, Institut für Nutzpflanzenwissenschaften und Ressourcenschutz - Pflanzenernährung (Prof. Werner) durchgeführt. Plant-soil interactions drive the input, cycling and losses of C and N in soil. This subproject aims at elucidating the input and fate of C in the soil-plant systems and its effect of N retention in soil under different paddy management (continuous vs. alternating with maize cropping). In particular we will investigate (i) how much of the assimilate C is released by the plants into the rhizosphere soil, and how this rhizodeposition is affected by N supply, soil density and crop variety during plant development, (ii) how the exudation of C and N responds to land use change, (iii) how C released into the rhizosphere affects the turnover of soil C and utilization of fertilizer N, and (iv) to what degree leaching contributes to the loss of C and N from the rooted surface soil. To answer these questions, we will combine the use of isotopic 13C and 15N labeling in laboratory and field experiments with a sophisticated characterization of root exudates, root border cells, and compound-specific isotope tracing in the residues of bacteria and fungi in rhizosphere, bulk soil as well as within different dissolved organic and inorganic carbon species in soil leachates. In this way and in collaboration with SP 2, 5, 6, and 7 of this research unit, our project links the cycling of C and N in paddy soils to one of its most prominent drivers, the release of organic compounds by roots.

Tierexperimentelle Untersuchungen zum Verhalten von PCB, HCB und HCH-Isomeren in der Nahrungskette Pflanze - Milchtier - Milch - Mensch

Das Projekt "Tierexperimentelle Untersuchungen zum Verhalten von PCB, HCB und HCH-Isomeren in der Nahrungskette Pflanze - Milchtier - Milch - Mensch" wird vom Umweltbundesamt gefördert und von Bundesanstalt für Milchforschung durchgeführt. Im Rahmen des Forschungsvorhabens werden Untersuchungen zum Vorkommen der genannten Verbindungen und ihr Verhalten in der Nahrungskette (Carry Over von Futtermitteln fuer Milchtiere in die Milch u.ae.) durchgefuehrt.

Energy Storage for Direct Steam Solar Power Plants (DISTOR)

Das Projekt "Energy Storage for Direct Steam Solar Power Plants (DISTOR)" wird vom Umweltbundesamt gefördert und von Deutsches Zentrum für Luft- und Raumfahrt e.V., Institut für Technische Thermodynamik durchgeführt. Objective: Solar thermal power plants represent today's most economic systems to generate electricity from solar insulation in them-range in regions like the Mediterranean area. By demonstrating the feasibility of direct steam generation in the absorber pipes European industry and research institutions have gained a leading position in this technology area. A key element foray successful market penetration is the availability of storage systems to reduce the dependence on the course of solarinsolation. The most important benefits result from -reduced internal costs due to increased efficiency and extended utilisation of the power block-facilitating the integration of a solar power plant into an electrical grid-adoption of electricity production to the demand thus increasing revenues Efficient storage systems for steam power plants demand transfer of energy during the charging/discharging process at constant temperatures. The DISTOR project focuses on the development of systems using phase change materials (PCM) as storage media. In order to accelerate the development, the DISTOR project is based on parallel research on three different storage concepts. These concepts include innovative aspects like encapsulated PCM, evaporation heat transfer and new design concepts. This parallel approach takes advantage of synergy effects and will enable the identification of the most promising storage concept. A consortium covering the various aspects of design and manufacturing has been formed from manufacturers, engineering companies and research institutions experienced in solar thermal power plants and PCM technology. The project will provide advanced storage material based on PCM for the temperature range of 200-300 C adapted to the needs of Direct Steam generation thus expanding Europe's strong position in solar thermal power plants.

Impact of transgenic crops on fertility of soils with different management history

Das Projekt "Impact of transgenic crops on fertility of soils with different management history" wird vom Umweltbundesamt gefördert und von Forschungsinstitut für biologischen Landbau Deutschland e.V. durchgeführt. What impact does transgenic maize have on soil fertility? Among the factors that determine soil fertility is the diversity of the bacteria living in it. This is in turn affected by the form of agriculture practiced on the land. What role do transgenic plants play in this interaction? Background Soil fertility is the product of the interactions between the parental geological material from which the soil originated, the climate and colonization by soil organisms. Soil organisms and their diversity play a major role in soil fertility, and these factors can be affected by the way the soil is managed. The type of farming, i.e. how fertilizers and pesticides are used, has a major impact on the fertility of the soil. It is known that the complex interaction of bacterial diversity and other soil properties regulates the efficacy of plant resistance. But little is known about how transgenic plants affect soil fertility. Objectives The project will investigate selected soil processes as indicators for how transgenic maize may possibly alter soil fertility. The intention is in particular to establish whether the soil is better able to cope with such effects if it contains a great diversity of soil bacteria. Methods Transgenic maize will be planted in climate chambers containing soils managed in different ways. The soil needed for these trials originates from open field trials that have been used for decades to compare various forms of organic and conventional farming. These soils differ, for example, in the way they have been treated with pesticides and fertilizers and thus also with respect to their diversity of bacteria. The trial with transgenic maize will measure various parameters: the number of soil bacteria and the diversity of their species, the quantity of a small number of selected nutrients and the decomposition of harvest residues. It will be possible to conclude from this work how transgenic plants affect soil fertility. Significance The project will create an important basis for developing risk assessments that incorporate the effects of transgenic plants on soil fertility.

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