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SP 1.2 Optimisation of soil organic matter management under intensive cropping in the North China Plain

Das Projekt "SP 1.2 Optimisation of soil organic matter management under intensive cropping in the North China Plain" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Kulturpflanzenwissenschaften (340), Fachgebiet Düngung und Bodenstoffhaushalt (340i) durchgeführt. Intensive maize-wheat double cropping is a common plant production system at the North China Plains. More than 600 kg N/ha as mineral N fertiliser are applied annually while only 300 to 350 kg N/ha are removed with plant products. Despite of this extraordinarily high level of N-fertilisation, the yield potential in the common wheat-maize cropping system is by far not fully taped yet. Beside low N utilization efficiencies (partly less than 30 percent), frequent lodging and environmental pollution including leaching and gaseous losses of N are the results of the excessive use of fertiliser-N. Within this study, different N-fertilisation, tillage and cropping strategies shall be investigated with their potential to maintain high levels of SOM and to guaranty high and stable yields in the long term in the North China Plain. Future developments like climate change and increasing demand for energy production from plant residues shall be considered. Special emphasis will be put on the fate of (fertilised) N which preferably should be available for plant uptake and built up of organic matter but may also disappear by leaching and gaseous losses. A combination of lab experiments, existing and newly established long term field experiments combined with computer modelling shall be used to extrapolate short and medium term findings into the future and up to a regional scale.

Water and global Change (WATCH)

Das Projekt "Water and global Change (WATCH)" wird vom Umweltbundesamt gefördert und von Potsdam-Institut für Klimafolgenforschung e.V. durchgeführt. Der globale Wasserkreislauf ist ein integraler Teil des Erdsystems. Er spielt eine zentrale Rolle in der globalen atmosphärischen Zirkulation, kontrolliert den globalen Energiekreislauf (mittels der latenten Wärme) und hat einen starken Einfluss auf die Kreisläufe von Kohlenstoff, Nährstoffen und Sedimenten. Global gesehen ist das Angebot an Frischwasser bei weitem größer als die menschlichen Bedürfnisse. Allerdings ist davon auszugehen, dass gegen Ende des 21. Jahrhunderts diese Bedürfnisse die gleiche Größenordnung erreichen werden wie das gesamte verfügbare Wasser. Für diverse Regionen jedoch übersteigt der Wasserbedarf (u.a. für die Landwirtschaft sowie die Nutzung in der Industrie und in den Haushalten) schon heute das regionale Angebot. Ansteigende CO2-Konzentrationen und Temperaturen führen zu einer Intensivierung des globalen Wasserkreislaufs und somit zu einem generellen Anstieg von Niederschlag, Abfluss und Verdunstung. Obwohl die Vorhersagen von zukünftigen Niederschlagsänderungen relativ unsicher sind, gibt es deutliche Hinweise, dass einige Regionen, wie z.B. der Mittelmeerraum, mit einer Abnahme des Niederschlags zu rechnen haben, während in einigen äquatornahen Regionen, wie z.B. Indien und der Sahelzone, der Niederschlag zunehmen wird. Hinzu kommt, dass sich auch jahreszeitliche Verläufe ändern könnten, die neue und manchmal auch unerwartete Probleme und Schäden verursachen können. Eine Intensivierung des Wasserkreislaufs bedeutet wahrscheinlich auch einen Anstieg in dessen Extremen, d.h. vor allem Überschwemmungen und Dürren. Es gibt Vermutungen, dass sich auch die interannuale Variabilität erhöhen wird und zwar einhergehend mit einer Intensivierung der El Nino und NAO-Zyklen, was zu mehr Dürren und großskaligen Hochwassersituationen führen würde. Diese Zyklen sind globale Phänomene, die diverse Regionen gleichzeitig beeinflussen, wenngleich dies oft auf verschiedene Art und Weise passiert.

How is the evolution of stratospheric ozone affected by climate change, and how strong is the feedback? (SHARP-OFC)

Das Projekt "How is the evolution of stratospheric ozone affected by climate change, and how strong is the feedback? (SHARP-OFC)" wird vom Umweltbundesamt gefördert und von Universität Bremen, Institut für Umweltphysik durchgeführt. One major goal of this project is to analyse updated observational trace gas data together with stateof- the art models (CTMs and CCMs) in order to obtain a better understanding of the interaction between ozone and climate change and the underlying dynamical and chemical processes. The extended satellite, balloon and aircraft observations combined with improved model calculations (CTM and CCM) are used to further reduce the uncertainties in the bromine budget, in particular the contribution from VSLS (very short lived substances) and to further elucidate on the role of iodine in the stratosphere. Furthermore detailed studies on the long-term evolution (trends and variability) of observed stratospheric trace gases with foci on profiles of O3, NO2 and aerosols retrieved from SCIAMACHY are proposed. Future evolution of stratospheric ozone will be investigated using updated EMAC CCM model runs, some of them in combination with an interactive atmosphere-ocean feedback. In addition to issues on the climate feedback on future ozone, particular emphasis will be given to the increasing role of N2O and GHG emissions.

Impacts of Solar Home System Usage in Rural Burkina Faso

Das Projekt "Impacts of Solar Home System Usage in Rural Burkina Faso" wird vom Umweltbundesamt gefördert und von Rheinisch-Westfälisches Institut für Wirtschaftsforschung e.V. RWI, Kompetenzbereich Umwelt und Ressourcen durchgeführt. In remote areas with low electrification rates, Solar Home Systems (SHS) can be seen as a promising alternative to the investment-intensive extension of the electricity grid. The Dutch Ministry of Foreign Affairs provides funding to a project in Burkina Faso that offers SHS to rural households using a market-based approach. The SHS that are distributed can provide electric lighting and - depending on the chosen capacity of the system - allow for the usage of small electric appliances up to colored television. As part of the series of impact evaluations of development activities supported by the Netherlands on behalf of the Dutch Ministry of Foreign Affairs, RWI and ISS assess the socio-economic impact of the usage of SHS such as improved living conditions, time savings, increased security, better health conditions, and educational attainment trough extended study hours. The idea is to conduct a difference-in-difference approach based on household surveys before and after the intervention, in combination with propensity score matching (PSM) to better match control and treatment households on pre-program characteristics (e.g. education, socio-economic status, income, asset-ownership, characteristics of the villages they live in). Following the roll-out plan of Yeelen Ba's activities, a baseline survey was conducted in November 2010 based on a random sample of villages that are in the program's catchment area. In total, 1,200 households in 40 villages (30 households per village) were interviewed. A particular focus was on the use of appliances and energy expenditures, as well as convenience and comfort aspects before and after the SHS was installed. For the difference-in-difference approach the sample will be divided into a treatment group consisting of households who will have obtained an SHS in the meantime and a control group consisting of untreated households. The follow-up survey will be conducted two years after the baseline survey in November 2012. All households will be revisited and differences in the changes in the outcome variables between the treatment group and the control group will be assessed, providing insights about how ownership of an SHS changes the socio-economic living conditions of the households.

AURORa - Investigation of the Radar Backscatter of Rain Impinging on the Ocean Surface

Das Projekt "AURORa - Investigation of the Radar Backscatter of Rain Impinging on the Ocean Surface" wird vom Umweltbundesamt gefördert und von Universität Hamburg, Zentrum für Meeres- und Klimaforschung, Institut für Meereskunde (IfM) durchgeführt. Over land, observations of rain rates are more or less operational. To obtain information about precipitation at the coastal zones, weather radars are used. However, over the oceans, especially away from the main shipping routes, no direct precipitation measurements are performed. In these regions, satellite data can provide information about precipitation events. Satellites deploying passive and active microwave sensors can operate independently of cloud cover and time of day. Passive microwave sensors give crude estimates of rain rates over large areas but cannot resolve small-scale rain events of short duration as are often observed in the tropics, for example. Active microwave sensors with high resolutions, such as synthetic aperture radars can provide more reliable information. Though the effect of rain on the atmosphere is a very topical area of research, the radar backscattering mechanisms at the water surface during rain events combined with wind are still not well understood. The purpose of this project is to investigate the radar backscattering from the water surface in the presence of rain and wind in order to interpret satellite radar data produced by active microwave sensors. Furthermore, the results should be embedded into models of the radar backscattering from the water surface to allow for estimating rain rates by using satellite data. Research topics: Rain impinging on a water surfaces generates splash products including crowns, cavities, stalks and secondary drops, which do not propagate, and ring waves and subsurface turbulence. We are investigating this phenomena at the wind-wave tank of the University of Hamburg. The tank is fitted with an artificial rain simulator of 2.3 m2 area mounted 4.5 m over the water surface. Rain drops of 2.1 and 2.9 mm in diameter with rain rates up to 100 mm/h have been produced. Wind with speeds 10 m/s and monomolecular slicks act on the water surface. The influence of the rain on the water surface is measured with a resistance type wire gauge, a two dimensional laser slope gauge and an coherent 9.8 GHz (x band) continuous wave scatterometer operating at VV-, HH- and HV-polarization. The influence of rain below the water surface is measured with colored raindrops which are observed with a video camera to investigate the turbulent motion and the depth of the mixed layer. At the North Sea Port of Buesum in Germany, a scatterometer operating at all polarizations and five frequencies will be mounted during summer of this year. The radar backscatter of the sea surface during rain events will be measured in combination with meteorological observations. With help of these measurements, existing radar backscatter models of the water surface will be improved for the presence of rain events. To validate the improved models, ERS-2 SAR-images will be compared with weather radar data.

A8:Transporte und Flüsse durch die Bodengrenzschicht

Das Projekt "A8:Transporte und Flüsse durch die Bodengrenzschicht" wird vom Umweltbundesamt gefördert und von Helmholtz-Zentrum für Ozeanforschung Kiel (GEOMAR) durchgeführt. The major goal of this new subproject is to estimate transport and fluxes of solutes between the bottom boundary layer, the stratified interior ocean and the ocean mixed layer on the continental slope and shelf regions of the Peruvian and Mauritanian Oxygen Minimum Zones (OMZ). The objectives will be achieved by estimating diapycnal and advective fluxes using two different methodological approaches: The first is basedon the measurement of the radium isotope distribution in sediments and in the water column. The second approach will use a combination of oceanographic measuring systems for the determination of turbulences, currents and hydrography. Subproject A8 will contribute to the understanding of the solute budget of the OMZ's and establishes a link between the benthic and pelagic research foci within the SFB 754.

Shift in the syncronisation of leaf decay processes in fragmented streams

Das Projekt "Shift in the syncronisation of leaf decay processes in fragmented streams" wird vom Umweltbundesamt gefördert und von Technische Universität Cottbus, Institut für Boden, Wasser, Luft, Lehrstuhl für Gewässerschutz, Forschungsstelle Bad Saarow durchgeführt. Climate change will increase summer droughts and cause both, premature leaf fall and temporary fragmentation of streams into a series of pools. This match of low flow situations with litter input is likely to alter litter processing. Based on results from Aquashift period 1, we hypothesise change of the invertebrate shredder community and shift among microbial and invertebrate leaf processing. These will change the dynamics of the energy supply of the benthic food web. In pools of summer-dry streams we will expose litter-bags (Alnus glutinosa (L.) Gaertn.) to assess mass loss, microbial colonisation (fungi, bacteria) and invertebrate shredding of leaves. Stepwise exclusion of larger invertebrates from litter-bags will assess the significance of suggested shift from dominance of large shredder (Gammarus) to small invertebrates (Chironomidae). In microcosm experiments we want to investigate the effect of factor combinations found in fragmented pools on microbial and invertebrate leaf processing. A leaf decay simulation model will be build in joint activity with the University Braunschweig to test significance of environmental factors. Linking the population dynamics model of Gammarus pulex at Univ. Braunschweig, the dynamics of FPOM production from leaves will be predicted under various climate change scenarios.

Programm zur Niedrigemissions-Technologie, Phase III - LOW NOx III

Das Projekt "Programm zur Niedrigemissions-Technologie, Phase III - LOW NOx III" wird vom Umweltbundesamt gefördert und von Motoren- und Turbinen Union Friedrichshafen durchgeführt. 1. Pilot Stage Combustor: In diesem Vorhaben wird das Konzept der Fett-Mager Verbrennung als Pilot-Stufe einer brennstoffgestuften Brennkammer untersucht. Dabei soll die Interaktion der Kuehlung, der fetten Stufe und der Mischluft derart optimiert werden, dass die Homogenitaet der fetten Stufe verbessert wird. 2. Applied CFD: In diesem Vorhaben werden Modelle, die die Interaktion der Waermefreisetzung mit der turbulenten Schwankungsbewegung getestet und anhand vorhandener Experimente verifiziert.

Effects of biochar amendment on plant growth, microbial communities and biochar decomposition in agricultural soils

Das Projekt "Effects of biochar amendment on plant growth, microbial communities and biochar decomposition in agricultural soils" wird vom Umweltbundesamt gefördert und von Forschungsinstitut für biologischen Landbau Deutschland e.V. durchgeführt. Biochar has a great potential to ameliorate arable soils, especially those that are low in organic matter due to intensive use or erosion. Biochar is carbonised organic material with high porosity that brings about changes in physical, chemical and biological soil functions. Biochar amended soils show a higher water and cation exchange capacity with reduced leaching and enhanced availability of plant nutrients. The microbial biomass in biochar amended soils is enhanced and more diverse. Biochar is stabilised organic material, which is likely to remain for hundreds of years in the soil. Photosynthetically fixed atmospheric CO2 stabilised in biochar may thus act as a direct carbon sink and help to mitigate climate change. As feedstock and production conditions produce different biochar qualities predictions of effects in soil need to consider biochar and soil properties case by case. To date biochar has been approved to ameliorate highly weathered tropical soils with positive effects on crop growth and yield. Distinct microbial groups were reported to be enhanced in soils but if this depends on the particular soil or biochar or a combination of both is an open question, especially in temperate climates. Likewise, it is not known if microorganisms colonising biochar surfaces are responsible for its mineralization or if they just use the new niches provided. The aim of the proposed project is to investigate the influence of two biochar types on soil-plant systems by determining i) soil nutrient availability, plant growth and nutrient uptake, ii) structure and function of soil microbial communities, iv) the decomposition and fate of biochar in soils. We will use two loessial soils from the well-known DOK-trial with different soil organic matter content. Other soils from the region will be selected to provide a wider range of soil quality, in particular pH. The biochars will be produced by pyrolysis and hydrothermal carbonization (HTC) from the C4-plant Miscanthus gigantea. Pyrolysis derived material has bigger pore sizes due to the evaporating gasses and is commonly alkaline, whereas the HTC derived biochar has a finer pore size, a much higher oxygen content and more acidic functional groups.

Teilprojekt: Entwicklung und Demonstration CO2 & H2O Adsorption aus Luft_M1

Das Projekt "Teilprojekt: Entwicklung und Demonstration CO2 & H2O Adsorption aus Luft_M1" wird vom Umweltbundesamt gefördert und von Climeworks Deutschland GmbH durchgeführt. Das Forschungsvorhaben 'SynLink' deckt die gesamte Wertschöpfungskette von der Kraftstoffherstellung aus Wasser, CO2 und erneuerbarer Elektroenergie bis hin zur Kraftstoffnutzung in verschiedenen mobilen Anwendungsbereichen ab - technisch und ökonomisch. Hierbei wird auf die Module 1 und 2 eingegangen. Über eine Co-Elektrolyse (Co-SOEC) soll aus Wasser und CO2 aus Luft sowie erneuerbarer Elektroenergie Synthesegas erzeugt werden, das über mehrere Synthesewege zu Kraftstoff umgewandelt werden kann. Zum einen wird eine Fischer-Tropsch-Synthese betrachtet, welche für langkettige Alkohole optimiert wird. In einem zweiten Syntheseweg wird Methanol aus Synthesegas mit vergleichsweise hohen CO2-Anteilen produziert. Die Syntheseprodukte sollen als Blends zu herkömmlichen fossilen Kraftstoffen wie Benzin, Kerosin und Diesel in gewünschten Verhältnissen beigemischt werden können. Die strombasierten Kraftstoffe werden in diesem Forschungsvorhaben in Pkws (Ottomotoren) sowie in Nutzfahrzeugen (Dieselmotoren) untersucht. Durch techno-ökonomische Analysen wird die Grundlage geschaffen diese Technologien mit den beteiligten Partnern nach dem Förderprojekt wirtschaftlich umsetzen zu können. Im Teilvorhaben 'Entwicklung und Demonstration CO2 & H2O Adsorption aus Luft' ist Climeworks für die folgende F&E verantwortlich: Verknüpfung der DAC-Technologie von Climeworks mit der Co-SOEC-Technologie von Sunfire, wobei insbesondere auf eine effiziente Anbindung von CO2 und Wasser fokussiert wird. Detail Engineering, Bau und Betrieb einer Climeworks DAC-3 Anlage mit einer Kapazität von ca. 120 Tonnen CO2 pro Jahr inklusive den damit durchzuführenden Versuchsreihen.

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