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Ozonvorlaeufer und deren Wirkung in der Troposphaere

Das Projekt "Ozonvorlaeufer und deren Wirkung in der Troposphaere" wird vom Umweltbundesamt gefördert und von Universität Bremen, Institut für Umweltphysik durchgeführt. Objective/Problems to be solved: Tropospheric ozone has a dual role with respect to climatic changes. Ozone is itself a greenhouse gas and it also plays a key role in the production of the hydroxyl radical (OH), which controls the lifetime of many climatically important tropospheric gases. Tropospheric ozone and OH are produced as a result of photochemical processes, through reactions involving ozone precursors. The proposed project is defined in order to answer three main questions: first, can the surface emissions of ozone precursors, and their variability be accurately quantified? Second, how should the current observations of chemical species be optimally coupled with chemistry-transport models (CTMs) to quantify the global budgets of ozone precursors and ozone ? Third, how do future changes in surface emissions and proposed future scenarios influence the lifetime of greenhouse gases and ozone distribution ? The project will provide a quantitative basis for emissions, distributions and evolution of chemical tropospheric species for discussions related to policies aimed at improving the quality of air or at reduction of greenhouse species anthropogenic emissions. Scientific objectives and approach: The overall objective of the project is to quantify accurately the budget of ozone precursors using a combination of observations and state of the art CTM. The retrieval methods to derive accurately the tropospheric burdens of CO, CH4, NO2 and ozone from observations provided by the IMG/ADEOS and GOME instruments will be improved. High resolution inventories of emissions for ozone precursors will be developed. The ability of several European CTMs to reproduce current distributions will be assessed, through detailed comparisons between model results and observations. The impact of changes in ozone precursors on the tropospheric oxidising capacity and on the distribution of ozone will be quantified. The relative importance of anthropogenic versus natural emissions in the ozone production will be quantified. The inverse modelling approach for quantifying surface emissions will be further developed. These developments will yield an assessment of the accuracy of current inventories. The impact of emission mitigation policies on the distributions of methane and ozone will be quantified.. Expected impacts: The proposed project addresses issues that are central to our understanding of the causes of large-scale air pollution and climate change, and will provide a quantitative basis for reducing the environmental and climatic impact of human activities. The new tools and data bases we will develop will aid the understanding of changes in the composition of the atmosphere and their consequences. The emissions distributions we will optimise could be used as a starting point for discussions on emissions reduction policies... Prime Contractor: Centre National de la Recherche Scientifique, FU 0005 - Institut Pierre-Simon Laplace; Guyancout/France.

Eisenlagerstaetten und Naehrstoffe im Ozean - Fortschritt der globalen Umweltsimulationen

Das Projekt "Eisenlagerstaetten und Naehrstoffe im Ozean - Fortschritt der globalen Umweltsimulationen" wird vom Umweltbundesamt gefördert und von Max-Planck-Institut für Meteorologie durchgeführt. Objective/Problems to be solved: The functioning of ocean ecosystems and their interaction with the global carbon cycle and the climate system is not very well known. Ocean Biogeochemical Climate Models (OBCM's) are still too simplistic to adequately describe observed changes in ocean biology and chemistry in space and time. Therefore large uncertainties remain concerning the carbon up-take by the ocean which also limits the predictability of the future carbon up-take. Scientific objective and approach: The work outlined seeks to better model marine ecosystems and the sources and sinks of C, N and other elements within those systems, assuming that a number of factors (notably light, N, P, Si, Fe) are co-limiting plankton blooms. This goal will be achieved through a combination of laboratory experiments, fieldwork and modelling. Laboratory work will target the predominant algal species of the major taxonomic groups and determine their growth as a function of multiple stresses, such as limitations of iron, light and macro-nutrients. This data will then be used to refine and improve ocean ecosystem models, with the aim to more accurately replicating observations of the natural system. New realistic OBCM' s will be developed for budgeting and exchanges of both CO2 and DMS, implementing (I) co-limitation by 4 nutrients of 5 major taxonomic classes of phyto-plankton, (II) DMS (P) pathways, (III) global iron cycling, (IV) chemical forms of iron and (V) iron supply into surface waters. Input from below of iron from anoxic sediments of coastal margins will be assessed along a 2-D vertical section from Europe into the centre of the north Atlantic. Input from above of Fe (II) dissolved in rainwater from Sahara dust blown over the central Atlantic will be quantified at sea, and related to observed plankton production, CO2 gas exchange and DMS emission. Different chemical forms of iron will be analysed and rigorous certification of all Fe in seawater data will be ensured. For 2 major DMS-producing algal groups the life cycle, Fe limitation, export production, CO2 uptake and DMS emissions will be synthesised from existing literature and laboratory experiments. Experimental data will be fed into an ecosystem model. Also DMS (P) pathway modelling will be carried out being expanded with 3 other groups of algal and DMS (P) pathways. The extended ecosystem model will provide reliable output for CO2/DMS gas exchange being implemented into two existing OBCM' s. Next climate change scenario' notably changes in Fe inputs, will be run, with special attention to climatic feedback (warming) on the oceanic cycles and fluxes. Expected impacts: Under the Kyoto Protocol, the European states have committed them selves to the quantification and prediction of future trends in the concentration of greenhouse gases in the atmosphere.. Prime Contractor: Netherlands Institute for Sea Research, Department of Marine Chemistry and Geology; Den Burg/Netherlands.

Ausrottungsrisiko und Wiedereinbuergerung von Pflanzenarten in einem zersplitterten Europa

Das Projekt "Ausrottungsrisiko und Wiedereinbuergerung von Pflanzenarten in einem zersplitterten Europa" wird vom Umweltbundesamt gefördert und von Universität Marburg, Fachbereich Biologie durchgeführt. Objective/Problems to be solved: It is every day experience in many European countries that the landscape is changing rapidly because of the multiplicity of demands on space made by e.g. agriculture, transport, recreation, city expansion. These human activities often develop at the expense of the habitats of wild plants and animals and their chances for survival resulting in a world wide decline in biodiversity. These conflicting demands on space require national but also European measures for the conservation of wildlife as detailed in the EU Habitats Directive and the Flora and Fauna Directive. A lot of conservation effort goes into restoring habitat quality, but we are now beginning to see that this is not enough to save rare and threatened species. This is simply because threatened species have dispersal problems in fragmented habitats. The remnant populations have become too small and too widely dispersed and these species therefore are unable to re-colonise the improved habitats. This is especially true for sessile long-lived organisms such as most plants. As a consequence an alarming, steadily increasing number of plant species appear on national red-data lists. What is lacking however, is an evaluation of the status of endangered plants on a European scale, considering their area of distribution as a whole, as plants have no nationality, in combination with an assessment of the chances for re-introduction as a conservation measure. Such a combination can help to make better environmental impact assessments and to reconcile conflicting demands on space. Scientific objectives and approach: The scientific objectives of the TRANSPLANT program are twofold: to investigate the extinction risks of plant species in fragmenting landscapes across Europe and secondly to develop scientifically sound re-introduction schemes and test their effectiveness. To achieve these goals, we will use a selected number of plant species that differ in their capacity to move across landscapes. This depends on two crucial traits: the longevity of adults and the dispersal capacity of seeds. The first trait determines the capacity to hold territory and function as a source of seeds in the landscape. The second trait affects the capacity to colonise new territory and settle elsewhere. Using these species as our guinea pigs we will built our expertise in a hierarchical, step-like fashion. First we need to know how isolation and small population size in remnants of these species have affected their genetic variation or in other words their capacity to adapt to changing environments. Than we will go on and measure longevity and dispersal capacity in the field in populations that differ in size and degree of isolation across their area of distribution. Prime Contractor: Katholieke Universiteit Nijmegen, Department of ecology and environment - Faculty of science; Nijmegen.

Molekulare Werkzeuge fuer die Bewertung des biologischen Sanierungspotentials an mit organischen Halogenen kontaminierten Standorten

Das Projekt "Molekulare Werkzeuge fuer die Bewertung des biologischen Sanierungspotentials an mit organischen Halogenen kontaminierten Standorten" wird vom Umweltbundesamt gefördert und von Gesellschaft für Biotechnologische Forschung mbH durchgeführt. Objective/Problems to be solved: Chlorinated hydrocarbons are the most important and widespread class of contaminants of soil and groundwater in all European countries and environmentally friendly methods have to be developed to abate this pollution. Many examples of bacterial transformation and, even, mineralisation of these compounds have been found. In field situations, stimulated or natural (intrinsic) bioremediation may, therefore, be a suitable remediation strategy for reducing risks. However, in practice, it is difficult to predict the bioremediation potential of the indigenous microbial population at polluted sites. Hence, there is a need for the development of effective, easy to handle tools for predicting degradative potential or for monitoring the effective stimulation of catabolic pathways in-situ. These tools should not be dependent on the culturability of contaminant-degrading organisms but, rather, be directed at the detection of the genes specific for microorganisms and genes encoding enzymes that catalyse the key reactions in the degradation pathways of contaminants. Scientific objectives and approach: Molecular detection methods will developed and optimised for the monitoring of bioremediation processes. A combination of detection of specific microorganisms, detection of catabolic genes and transformation activity, all in-situ, will allow the accurate analysis of in-situ natural attenuation. Results of the characterisation of intrinsic potentials of organohalogen-polluted sites by classical microcosm studies will be used to assess the usefulness of the molecular tools developed during the time-course of the project. A knowledge base created by the detailed genetic and biochemical characterisation of a collection of DNA segments encoding catabolic genes, will be used for the development of probes and primers for extracting the broadest possible diversity of genes from the environment. A database relating genetic structure to metabolic function for various key enzymes of halogenated hydrocarbon degradation will be built up and after optimisation of protocols for isolating DNA and RNA from environmental samples, as well as the adaptation of quantitative PCR methods, used for the development of specific probes and primers to analyse and quantify the presence and expression of degradative pathways in contaminated samples, to characterise enrichment cultures and to monitor the evolution of dechlorinating activity in microcosms. Results of this validation phase will be used to optimise the molecular tools already available. Finally, newly developed and optimised methods will be converted to an economic method to identify and quantify by molecular methods the natural attenuation potential of contaminated sites...

Natuerliche Ausgangsqualitaet in europaeischen Grundwasserleitern: Grundlage fuer die Grundwasserleiterbewirtschaftung

Das Projekt "Natuerliche Ausgangsqualitaet in europaeischen Grundwasserleitern: Grundlage fuer die Grundwasserleiterbewirtschaftung" wird vom Umweltbundesamt gefördert und von Universität Bern, Physikalisches Institut durchgeführt. Objective/Problems to be solved: There is currently no standard to assess the natural baseline quality of groundwater. This is required: a) as a basis for defining pollution and b) because existing limits are breached by entirely natural processes. The present-day baseline inorganic and organic geochemistry will be investigated using selected reference aquifers as well as historical water quality trends in these aquifers. State-of-the-art chemical, isotopic and radiometric tracer techniques and geochemical modelling will be used to define timescales of the natural geochemical processes. The results will be used as a scientific basis for underpinning the emerging Water Framework Directive and for making recommendations for monitoring natural aquifer systems. This will be achieved by working closely with an advisory group drawn from regulatory bodies in the consortium. The results will be presented through scientific channels, for use by policy makers and legislators. Scientific objectives and approach: The objective of the BASELINE project is to establish criteria for defining natural water quality baselines and develop a standardised Europe-wide approach for use in the emerging Water Framework Directive. Such a standard, based on geochemical principles, is needed to be able to assess scientifically the natural variations in groundwater quality since these alone may breach existing health limits. These criteria are also needed as a reference to assess quantitatively whether anthropogenic pollution is taking place. The project will also focus on timescales influencing the natural processes and the rates at which these are occurring and appropriate dating tools (including radioisotopes and CFC's) will be used. The extent to which pristine waters are being depleted by contaminated waters moving into the aquifer will also be assessed. As well as giving the scientific framework, this project will provide a forum for discussion with policy makers and end users, including the utilities and general public. The work will be conducted in a number of representative aquifer cross sections in both carbonate and non-carbonate terrain in groundwater catchments in several European countries (Estonia, Poland, Denmark, Belgium, France, UK, Spain and Portugal). Expected impacts: The expected impacts will relate both to advances in science as well as firm policy recommendations and material for end-users. This will include recommendations to EU (EEA) on how the baseline concept can help to underpin policy decisions relating to water quality including monitoring practice at European level. The improved understanding of the natural properties of groundwater, its quality, residence times and distribution will have an impact on decisions relating to the sustainable uses of water in Europe as well as on the role of groundwater in the environment in general. Prime Contractor: Natural Environment Research Council, British Geological Survey Hydrogeology Group; Wallingford/UK

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