API src

Found 478 results.

Bebauungspläne Mettlach/Orscholz - BPlan Auf dem Unner

Bebauungspläne und Umringe der Gemeinde Mettlach (Saarland), Ortsteil Orscholz:Bebauungsplan "BPlan Auf dem Unner" der Gemeinde Mettlach, Ortsteil Orscholz

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.

Estimation of willingness-to-pay to reduce risks of exposure to heavy metals and cost-benefit analysis for reducing heavy metals occurence in Europe (ESPREME)

Das Projekt "Estimation of willingness-to-pay to reduce risks of exposure to heavy metals and cost-benefit analysis for reducing heavy metals occurence in Europe (ESPREME)" wird vom Umweltbundesamt gefördert und von Universität Stuttgart, Institut für Energiewirtschaft und Rationelle Energieanwendung durchgeführt. Heavy metals from different sources accumulate in the environment. From a policy point of view, it has been difficult to tackle the environmental problems due to heavy metals partly because the problem has been viewed from different policy domains (air, water, soils etc.). Thus, it is not guaranteed that the policy mix applied under environmental regulation is optimal. A systems analysis would be required to define the sources of heavy metals, how they are dispersed in the environment and which adverse effects they might cause on human and ecosystems health. From a policy point of view, it is also important to identify what kinds of policy responses would be most cost-effective to reduce the impacts of heavy metals. Such information is required for carrying out cost-benefit analyses of reducing the occurrence of heavy metals in our society. Identifying the benefits would include a monetary valuation of the impacts with contingent valuation (CV) approaches (e.g. assessing the willingness-to-pay, WTP). The focus of the work described will be on priority metals, which are mercury, cadmium, chrome, nickel, arsenic and lead. Core aim of the research is to carry out cost effectiveness (CEA) and cost-benefit analyses (CBA) for reducing the heavy metals occurrence, in the EU Member States and candidate countries, including damage assessment to the environment and human health in the long term following the impact pathway analysis which assesses the impacts and damages of pollutants from their emissions over their dispersion to exposure and impacts. Finally, a feasibility study will be conducted to identify the potentials, strengths and weaknesses and uncertainties of currently available macro-economic models to identify further research needs in this field.

Impact of long-term exposure to elevated pCO2 on activity and populations of free living N2 fixing organisms in a temperate grassland system

Das Projekt "Impact of long-term exposure to elevated pCO2 on activity and populations of free living N2 fixing organisms in a temperate grassland system" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Tropische Agrarwissenschaften (Hans-Ruthenberg-Institut), Fachgebiet Pflanzenbau in den Tropen und Subtropen (490e) durchgeführt. The project aims at achieving a better understanding of the processes that drive or limit the response of grassland systems in a world of increasing atmospheric pCO2. We will test the hypothesis that the previously shown increase in below-ground allocation of C under elevated pCO2 provides the necessary energy excess and will stimulate free-living N2 fixers in a low N grassland environment. The project thus aims at assessing the occurrence and importance of free-living N2 fixers under elevated pCO2 and identify the associated microbial communities involved in order to better understand ecosystems response and sustainability of grassland systems. This project had the last opportunity to obtain soil samples from a grassland ecosystem adapted to long-term (10 year) elevated atmospheric pCO2 as the Swiss FACE experiment. The project aims to identify the relevant components of free-living diazotrophs of the microbial community using 15N stable isotope - DNA probing.

Der Einfluss der SML auf die Spurengasbiogeochemie und den Ozean-Atmosphäre-Gasaustausch

Das Projekt "Der Einfluss der SML auf die Spurengasbiogeochemie und den Ozean-Atmosphäre-Gasaustausch" wird vom Umweltbundesamt gefördert und von Helmholtz-Zentrum für Ozeanforschung Kiel (GEOMAR), Forschungsbereich 2: Marine Biogeochemie durchgeführt. Labor- und Feldstudien zeigen, dass die Oberflächengrenzschicht des Ozeans (â€Ìsurface microlayerâ€Ì, kurz SML) die biogeochemischen Kreisläufe von klimaaktiven und atmosphärisch wichtigen Spurengasen wie Kohlenstoffdioxid (CO2), Kohlenstoffmonoxid (CO), Methan (CH4), Lachgas (N2O) und Dimethylsulfid (DMS) stark beeinflusst: (i) Jüngste Studien aus den PASSME- und SOPRAN-Projekten haben hervorgehoben, dass Anreicherungen von oberflächenaktiven Substanzen (d.h. Tensiden) einen starken (dämpfenden) Effekt sowohl auf die CO2- als auch auf die N2O-Flüsse über die SML/Atmosphären-Grenzfläche hinweg haben und (ii) Spurengase können durch (mikro)biologische oder (photo)chemische Prozesse in der SML produziert und verbraucht werden. Daher kann der oberste Teil des Ozeans, einschließlich der SML, verglichen mit dem Wasser, das in der Mischungsschicht unterhalb der SML zu finden ist, eine bedeutende Quelle oder Senke für diese Gase sein, was von sehr großer Relevanz für die Forschungseinheit BASS ist. Die Konzentrationen von CO2, N2O und anderen gelösten Gasen in der SML (oder den oberen Zentimetern des Ozeans) unterscheiden sich nachweislich von ihren Konzentrationen unterhalb der SML. Typischerweise werden die Nettoquellen und -senken wichtiger atmosphärischer Spurengase mit Konzentrationen berechnet, die in der Mischungsschicht gemessen wurden und mit Gasaustauschgeschwindigkeiten, die die SML nicht berücksichtigen. Diese Diskrepanzen führen zu falsch berechneten Austauschflüssen, die in der Folge zu großen Unsicherheiten in den Berechnungen der Klima-Antrieben und der Luftqualität in Erdsystemmodellen führen können. Durch die Verknüpfung unserer Spurengasmessungen mit Messungen von (i) der Dynamik und den molekularen Eigenschaften der organischen Materie und speziell des organischen Kohlenstoffs (SP1.1; SP1.5), (ii) der biologischen Diversität und der Stoffwechselaktivität (SP1.2), (iii) den optischen Eigenschaften der organischen Materie (SP1.3), (iv) der photochemischen Umwandlung der organischen Materie (SP1.4) und (v) den physikalischen Transportprozessen (SP2.3) werden wir ein umfassendes Verständnis darüber erlangen, wie die SML die Variabilität der Spurengasflüsse beeinflusst.

Steady-State Dilution and Mixing-Controlled Reactions in Three-Dimensional Heterogeneous Porous

Das Projekt "Steady-State Dilution and Mixing-Controlled Reactions in Three-Dimensional Heterogeneous Porous" wird vom Umweltbundesamt gefördert und von Eberhard Karls Universität Tübingen, Zentrum für Angewandte Geowissenschaften (ZAG), Arbeitsgruppe Hydrogeology durchgeführt. Understanding transport of contaminants is fundamental for the management of groundwater re-sources and the implementation of remedial strategies. In particular, mixing processes in saturated porous media play a pivotal role in determining the fate and transport of chemicals released in the subsurface. In fact, many abiotic and biological reactions in contaminated aquifers are limited by the availability of reaction partners. Under steady-state flow and transport conditions, dissolved reactants come into contact only through transverse mixing. In homogeneous porous media, transverse mixing is determined by diffusion and pore-scale dispersion, while in heterogeneous formations these local mixing processes are enhanced. Recent studies investigated the enhancement of transverse mixing due to the presence of heterogeneities in two-dimensional systems. Here, mixing enhancement can solely be attributed to flow focusing within high-permeability inclusions. In the proposed work, we will investigate mixing processes in three dimensions using high-resolution laboratory bench-scale experiments and advanced modeling techniques. The objective of the proposed research is to quantitatively assess how 3-D heterogeneity and anisotropy of hydraulic conductivity affect mixing processes via (i) flow focusing and de-focusing, (ii) increase of the plume surface, (iii) twisting and intertwining of streamlines and (iv) compound-specific diffusive/dispersive properties of the solute species undergoing transport. The results of the experimental and modeling investigation will allow us to identify effective large-scale parameters useful for a correct description of conservative and reactive mixing at field scales allowing to explain discrepancies between field observations, bench-scale experiments and current stochastic theory.

Mycorrhizal response and nutrient uptake of old, new and organically bred winter wheat cultivars in low input systems

Das Projekt "Mycorrhizal response and nutrient uptake of old, new and organically bred winter wheat cultivars in low input systems" wird vom Umweltbundesamt gefördert und von Forschungsinstitut für Biologischen Landbau durchgeführt. The testing of crop cultivars on organic and conventional farms is often confounded by site heterogeneity. We compared the performance of a set of old, conventionally and organically bred winter wheat (Triticum aestivum L.) cultivars within the DOK long term trial in CH-Therwil in 2007. In the DOK trial organic and conventional farming systems are compared since 1978 in a split-split plot design with four replicates on a haplic luvisol. Yield (dry matter yield, thousand kernel weight, harvest index and nitrogen harvest index) and quality parameters (grain protein content, Hagberg falling number, Zeleny value, wet gluten content and gluten index) of ten cultivars were assessed in four systems: unfertilized control (NOFERT), bio-dynamic (BIODYN 1 and 2) and one conventional farming system (CONMIN) with different levels of total nitrogen inputs (0, 33, 66 and 140 kg ha-1, respectively). Effects of cultivars and systems on yield and quality parameters were statistically significant, genotype x system interactions were generally not detected. Grain yield increased from 2.7 (NOFERT), 3.7 (BIODYN 1), 4.2 (BIODYN 2) up to 6.8 t ha-1 for the conventional system CONMIN with an average protein content of 10.8, 9.4, 9.0 and 11.7%, respectively. No significant differences between cultivars were detected for yield in the organic system BIODYN 2, whereas in the conventional system CONMIN, cultivars bred under conventional conditions yielded significantly more than old cultivars. However, the protein content of old cultivars was significantly higher than that of modern cultivars. The results imply that breeding for yield was successful during the last century but only under high input conditions (7.6 kg ha-1 yr-1 in the conventional system CONMIN), where the development was accompanied by rising inputs of external resources (e.g. mineral fertilizers). Under organic conditions, yield increase with the year of release of cultivars was only 1.8 kg ha-1 yr-1 (in the organic system BIODYN 2) and modern cultivars could not outperform the old cultivars, irrespective of their selection environment. A redundancy analysis showed that yield was mainly determined by systems or the input of fertilizers, while the influence of cultivars was only minor. The redundancy analysis for baking quality parameters in contrast revealed that the influence of cultivars was higher than the influence of the systems. It is suggested, that long term system comparisons can ideally serve to test crop cultivars under identical soil and climatic conditions. Root colonization with arbuscular mycorrhizal fungi (AMF) was higher under organic than under conventional farming conditions but there was no evidence that breeding conditions were influencing AMF-root colonization of the different cultivars. We observed a positive correlation for AMF root colonization and shoot P at tillering and flowering under organic but not under conventional conditions. (abridged text)

SFB Waldoekosystemsanierung

Das Projekt "SFB Waldoekosystemsanierung" wird vom Umweltbundesamt gefördert und von Universität für Bodenkultur Wien, Institut für Botanik durchgeführt. Projektteil 2 des Spezialforschungsbereiches'Waldoekosystemsanierung'. Interpretation of water stress indicators from soil parameters.

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.

Element cycles in mountain regions under various land use

Das Projekt "Element cycles in mountain regions under various land use" wird vom Umweltbundesamt gefördert und von Universität Bayreuth, Fachgruppe Geowissenschaften, Bayreuther Zentrum für Ökologie und Umweltforschung (BayCEER), Lehrstuhl für Agrarökosystemforschung durchgeführt. Research question: What is the role of agricultural land use in changes of nutrient cycles and losses dependingon surface slope and climate? Approach: Annual balance of main nutrients for 3-4 main agricultural farms based on fertilizer input, partitioning of nutrients in above and below ground plant parts, output with harvest, losses with DOM and erosion (in collaboration with other TP). The balances will be done depending on agricultural practices in Eger and Haean Catchment and will be compared with adjacent grassland and forest. Obtained element cycles will be upscaled from farm area to the level of both catchments basins depending on specific land use, surface slope and climate. Research question: Can we reconstruct previous erosion and nutrient losses and separate them under forest and under agricultural use? Approach: Undisturbed sediment cores (7 for Eger and 7 for Haean) will be taken from the lakes and soils of landscapes subordinated to agricultural fields. Three radiocarbon data of wood particles at increasing depth for each sediment core will be used as references. The age of the bottom sediment layer should be less than 1000 years. The total content of C, N, P, K, Mg, Ca, Si will be analyzed in individual laminae or sediment layers. Conclusions will be drawn based on the thickness of the laminae, their elements content and the ratio between nutrients and Si. The conclusions will be proven by 13C (vegetation change) and 15N (N input by fertilizers) of individual laminae. Research question: What are the best management practices for sloping uplands? Approach: Measured element cycles and losses under various agriculture practice will be analysed and practices with the least nutrient losses and erosion will be selected. The best management practices for landscapes with different slopes will be elaborated.

1 2 3 4 546 47 48