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Evaluating current European agri-environment schemes to quantify and improve nature conservation efforts in agricultural landscapes (EASY)

Research question: Agri-environment schemes play an increasingly important role in European CAP (Common Agricultural Policy) to support biodiversity and environment in agricultural landscapes. They have been implemented since 1992 and now cost a yearly 1.7 billion Euro. Still, there is no conclusive evidence that these schemes actually do contribute to the conservation of particularly biodiversity. The primary objective of this project is to evaluate the (cost-) effectiveness of European agri-environment schemes in protecting biodiversity and to determine the primary processes that determine their effectiveness. This project furthermore aims to determine how CAP may be introduced in candidate EU-members without unacceptable loss of biodiversity. It will provide simple guidelines how researchers, governmental authorities may efficiently evaluate agri-environmental measures. Aim: Agri-environment schemes have been used to protect biodiversity and environment in agricultural areas since 1992. Their effectiveness has never been reliably evaluated. This project aims to evaluate the (cost-)effectiveness of agri-environment schemes with respect to biodiversity conservation in five European countries. It will determine the proper scales that have to be addressed for conservation efforts for a range of species groups. It will determine the most important environmental factors that influence the effectiveness of the schemes. Based on this, recommendations will be made how the effectiveness of schemes may be improved and simple guidelines will be produced how ecological effects of agri-environment schemes can be evaluated efficiently by governmental authorities or other institutions. The ecological effects of the introduction of CAP in a candidate EU-member will be investigated to reduce negative side effects of anticipated land-use changes Scientific methods: We will examine the effectiveness of agri-environment schemes by surveying pairs of fields: a field with an agri-environment scheme and a nearby field that is conventionally managed. In five countries, in each country in three areas, and in each area on seven pairs of fields the species richness of birds, plants and three insect groups (pollinators, herbivores, predators) will be determined. Effects of schemes on pollination efficiency and pest control will be examined using indicator communities. Correlative studies will examine the effects of landscape structure, land-use intensity and species pool on the effectiveness of agri-environmental measures. The spatial scale that is relevant to nature conservation efforts will be investigated via the spatial distribution of species groups. The results will be used to formulate recommendations how to improve the effectiveness of agri-environment schemes and to construct a set of simple guidelines how schemes can be evaluated efficiently yet reliably.

Forschergruppe (FOR) 1525: INUIT - Ice Nuclei research UnIT, Vom Labor ins Feld: Untersuchungen zum Immersionsgefrieren von atmosphärenrelevanten Eisnukleationskeimen

Das hier vorgeschlagene Projekt, RP6 in INUIT-2, zielt darauf hin, fundamentales Prozessverständnis in Bezug auf heterogene Eisnukleation zu erzielen, und hier besonders auf die Rolle von biogenen Eiskeimen und von Eiskeimen die aus Mischungen von biogenem und mineralischem Material bestehen. Der Leipzig Aerosol Cloud Interaction Simulator (LACIS) wird dazu verwendet werden, das Immersionsgefrierverhalten einer Reihe von verschiedenen Eiskeimen zu untersuchen, darunter biogene (von Pilzen stammende) Eiskeime, solche die aus einer Mischung von biogenem und mineralischem Material bestehen wie Bodenstäube und Proben die innerhalb von INUIT-2 als Test-Materialen verwendet werden. Letztere werden von verschiedenen Gruppen von innerhalb und außerhalb von INUIT vermessen werden, und die Ergebnisse werden Vergleichen unterzogen werden, ähnlich denen, die bereits für einfachere Test-Materialien in INUIT-1 erfolgreich durchgeführt worden sind. Für die Eiskeime, die zur Untersuchung in RP6 vorgeschlagen werden, wird in sinnvollen und machbaren Fallen eine Oberflächenbehandlung durchgeführt werden, mit reaktiven und mit chemisch inerten Substanzen, deren Einfluss auf die Eiskeimfähigkeit dann untersucht wird. Wie bereits in früheren LACISStudien dokumentiert, sind kontrollierte Oberflächenbehandlungen ein ausgezeichnetes Instrument um zu ermitteln, was dazu führt, dass ein Partikel ein effektiver Eiskeim ist. Zusätzlich erhellen diese Untersuchungen den Effekt der Alterung auf die Eiskeime. Es ist auch geplant, die Messungen auszuweiten, hin zu Bedingungen unter denen eine Untersättigung bezüglich Wasserdampf vorliegt. Es soll untersucht werden in wie weit sich die Eiskeimbildung unter diesen Bedingungen verhält wie es im Fall von Immersionsgefrieren in konzentrierten Lösungen zu erwarten wäre. Von all den experimentell erhaltenen Daten werden verschiedene Parametrisierungen abgeleitet, sowohl zeit-abhängige als auch zeit-unabhängige, die dann der Wissenschaftsgemeinschaft für die weitere Verwendung in Modellen zur Verfügung gestellt werden. Die hier vorgeschlagenen Studien werden die bereits erfolgreich an LACIS während INUIT-1 durchgeführten Arbeiten ergänzen, da die Arbeiten in INUIT-1 stärker auf die Untersuchung reiner Mineralstäube und reiner biogener Substanzen hinzielten. Die Untersuchung von komplexeren und entsprechend mehr atmosphärenrelevanten Eiskeimen wird signifikant dazu beisteuern, atmosphärische Eiskeimbildung generell besser zu verstehen, und die entsprechenden Beiträge von mineralischen und biogenen Substanzen zu quantifizieren.

Natural Forest Management in Caracarai, Roraima, Brazil

Objectives: Sustainable management of tropical moist forests through private forest owners will become increasingly important. Media report that in Brazil, particularly in Amazonia, approx. 80 percent of the timber harvested is from illegal sources. Private management of forests according to internationally acknowledged standards offers an opportunity to significantly lower the portion of illegally cut timber. Moreover, it contributes significantly to the conservation of the Amazon forest. Private forest owners show a clear long-term commitment towards the implementation of management standards according that is ecologically compatible, socially acceptable and economically viable. The project area, a pristine forest in legal Amazonia in the transition zone between moist tropical forests and savannas (cerrado), is extremely diverse in floristic and faunistic terms. The institute cooperates with the private forest owner. Main tasks are to document the faunistic and floristic diversity, to calculate the Annual Allowable Cut and to elaborate concepts for site-specific silviculture. Results: To date (Oct. 2006) the following activities were started: - a comprehensive inventory system for planning at the FMU-level has been successfully introduced; - the inventory system for the annual coupe area has been designed and data for the first coupe are being processed; - the annual allowable cut is currently calculated based on the results of the above described inventories; - two fauna surveys are completed; one focusing on large mammals and one on the avi-fauna. A long-term monitoring concept to assess the influence of forest management on the faunistic diversity is currently under development; - forest zoning is completed applying terrestrial surveys and interpreting high-resolution satellite images; - a study on the use of Bethollethia excelsa-fruits (Brazil nuts) is currently implemented; - a study on timber properties of lesser known species is currently implemented.

Forschergruppe (FOR) 1740: Ein neuer Ansatz für verbesserte Abschätzungen des atlantischen Frischwasserhaushalts und von Frischwassertransporten als Teil des globalen Wasserkreislaufs, Variation of the fresh water in the western Nordic Seas

The goal of this project is to capture and analyse fluctuations of the fresh water in the western Nordic Seas and to understand the related processes. The East Greenland Current in the Nordic Seas constitutes an important conduit for fresh water exiting the Arctic Ocean towards the North Atlantic. The Arctic Ocean receives huge amounts of fresh water by continental runoff and by import from the Pacific Ocean. Within the Arctic Ocean fresh water is concentrated at the surface through sea ice formation. The East Greenland Current carries this fresh water in variable fractions as sea ice and in liquid form; part of it enters the central Nordic Seas, via branching of the current and through eddies. It controls the intensity of deep water formation and dilutes the water masses which result from convection. The last decades showed significant changes of the fresh water yield and distribution in the Nordic Seas and such anomalies were found to circulate through the North Atlantic. In this project the fresh water inventory, its spatial distribution and its pathways between the East Greenland Current and the interior Greenland and Icelandic seas shall be captured by autonomous glider missions. The new measurements and existing data will, in combination with the modeling work of the research group, serve as basis for understanding the causes of the fresh water variability and their consequences for the North Atlantic circulation and deep water formation.

Schwerpunktprogramm (SPP) 1158: Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Bereich Infrastruktur - Antarktisforschung mit vergleichenden Untersuchungen in arktischen Eisgebieten, Investigation of mechanism driving glacial/interglacial variability in stratification/mixing and biological productivity of the Pacific Southern Ocean and potential implications on air-sea CO2-exchange: synthesis of climate and ocean biogeochemical modeling with paleoceanographic reconstructions

Atmospheric CO2 concentrations present a repetitive pattern of gradual decline and rapid increase during the last climate cycles, closely related to temperature and sea level change. During the Last Glacial Maximum (LGM; 23-19 kyr BP), when sea level was ca. 120 m below present, the ocean must have stored additionally about 750 Gt carbon. There is consensus that the Southern Ocean represents a key area governing past and present CO2 change. The latter is not only of high scientific but also of socio-economic and political concern since the Southern Ocean provides the potential for an efficient sink of anthropogenic carbon. However, the sensitivity of this carbon sink to climate-change induced reorganizations in wind patterns, ocean circulation, stratification, sea ice extent and biological production remains under debate. Models were not yet able to reproduce the necessary mechanisms involved, potentially due to a lack of the dynamic representation/resolution of atmospheric and oceanic circulation as well as missing carbon cycling. Data on past Southern Ocean hydrography and productivity are mainly from the Atlantic sector, thus do not adequately document conditions in the Pacific sector. This sector is not only the largest part of the Southern Ocean, but it also represents the main drainage area of the marine-based West Antarctic Ice Sheet (WAIS). In the proposed study we aim to generate paleo-data sets with a newly established proxy method from sediment core transects across the Pacific Southern Ocean. This will enhance the baselines for the understanding and modeling of the Southern Ocean's role in carbon cyling, i.e. ocean/atmosphere CO2 exchange and carbon sequestration. It will also allow insight into the response of the WAIS to past warmer than present conditions. Paired isotope measurements (oxygen, silicon) will be made on purified diatoms and radiolarians to describe glacial/interglacial contrasts in physical and nutrient properties at surface and subsurface water depth. This will be used to test (i) the impact of yet unconsidered dust-borne micronutrient deposition on the glacial South Pacific on shifts of primary productivity, Si-uptake rates and carbon export, (ii) the 'silicic-acid leakage' hypothesis (SALH) and (iii) the formation and extent of surface water stratification. Diatom and radiolarian oxygen isotopes will provide information on the timing of surface ocean salinity anomalies resulting from WAIS melt water. Climate model simulations using a complex coupled atmosphere ocean general circulation model (AOGCM) in combination with a sophisticated ocean biogeochemical model including Si-isotopes will be used for comparison with the paleo records. The analysis will cover spatial as well as temporal variability patterns of Southern Ocean hydrography, nutrient cycling and air-sea CO2-exchange. With the help of the climate model we aim to better separate and statistically analyse the individual impacts of ocean circulation and bio

Rehabilitation of Degraded Forests in Yunnan (German-Chinese Cooperation for Agrarian Research)

Background: An increasing frequency of massive flooding along the lower Yangtse River in China ended in a disastrous catastrophe in summer 1998 leaving several thousand people homeless, more than 3.600 dead and causing enormous economic damage. Inappropriate land-use techniques and large scale timber felling in the water catchment of the upper Yangtse and its feeder streams were stated to be the main causes. Immediate timber cutting bans were imposed and investigations on land use patterns were initiated by the Chinese Government. The Institute for World Forestry of the Federal Research Centre for Forestry and Forest Products was approached by the Yunnan Academy of Forestry in Kunming to exchange experiences and to cooperate scientifically in the design and application of appropriate afforestation and silvicultural management techniques in the water catchment area of the Yangtse. This cooperation was initiated in 1999 and is based on formal agreements in the fields of agrarian research between the German and Chinese Governments. Objectives: The cooperation was in the first step focussing on the identification of factors which caused the enormous floodings. After their identification measures of prevention were determined and put into practice. In this context experiences made in past centuries in the alpine region of central Europe served as an incentive and example for similar environmental problems and solutions under comparable conditions. Relevant key questions of the cooperation project were: - Analysis of forest related factors influencing the recent floodings of the Yangtse, - Analysis and evaluation of silvicultural management experiences from central Europe for know-how transfer, - Evaluation of rehabilitation measures for successful application in Yunnan, - Dissemination of knowledge through vocational training. Results: - Frequent wild grazing of husbandry is a key factor for forest degeneration beyond unsustainable timber harvests, forest fires and insect calamities leading to increased water run-off in the mountainous region of Yunnan; - Browsing of cattle interrupts succession thus avoiding natural regeneration and leaving a logging ban ineffective; - Mountain pasture in the Alps had similar effects in the past in central Europe. The introduction of controlled grazing has led to an ecologically compatible coexistence of pasture and ecology. Close-to-nature forestry can have positive effects in this sensitive environment. - Afforestation with site adopted broadleaves and coniferous tree species was implemented on demonstration level using advanced techniques in Yunnan.

Barley dwarfs acting big in agronomy. Identification of genes and characterization of proteins involved in dwarfism, lodging resistance and crop yield

Barley (Hordeum vulgare) is an important cereal grain which serves as major animal fodder crop as well as basis for malt beverages or staple food. Currently barley is ranked fourth in terms of quantity of cereal crops produced worldwide. In times of a constantly growing world population in conjunction with an unforeseeable climate change and groundwater depletion, the accumulation of knowledge concerning cereal growth and rate of yield gain is important. The Nordic Genetic Resource Center holds a major collection of barley mutants produced by irradiation or chemical treatment. One phenotypic group of barley varieties are dwarf mutants (erectoides, brachytic, semidwarf, uzu). They are characterized by a compact spike and high rate of yield while the straw is short and stiff, enhancing the lodging resistance of the plant. Obviously they are of applied interest, but they are also of scientific interest as virtually nothing is known about the genes behind the development of plant dwarfism. The aim of this project is to identify and isolate the genes carrying the mutations by using state of the art techniques for gene cloning at the Carlsberg Laboratory. The identified genes will be connected with the mutant phenotype to reveal the gene function in general. One or two genes will be overexpressed and the resulting recombinant proteins will be biochemically and structurally characterized. The insights how the mutation effects the protein will display the protein function in particular. Identified genes and their mutant alleles will be tested in the barley breeding program of the Carlsberg brewery.

Forest management in the Earth system

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.

Biogeochemical interface formation in soils as controlled by different components

We consider clay minerals, iron oxides and charcoal as major components controlling the formation of interfaces relevant for sorption of organic chemicals, as they control the assemblage of organic matter and mineral particles. We studied the formation of interfaces in batch incubation experiments with inoculated artificial soils consisting of model compounds (clay minerals, iron oxide, char) and natural soil samples. Results show a relevant contribution of both iron oxides and clay minerals to the formation of organic matter as sorptive interfaces for hydrophobic compounds. Thus, we intend to focus our work in the second phase on the characterization of the interface as formed by organic matter associated with clay minerals and iron oxides. The interfaces will be characterized by the BET-N2 and ethylene glycol monoethyl ether (EGME) methods and 129Xe and 13C NMR spectroscopy for determination of specific surface area, sorptive domains in the organic matter and microporosity. A major step forward is expected by the analysis of the composition of the interface at different resolution by reflected-light microscopy (mm scale), SEM (scanning electron microscopy, micrometer scale) and secondary ion mass spectrometry at the nanometer scale (nanoSIMS). The outcomes obtained in combination with findings from cooperation partners will help to unravel the contribution of different types of soil components on the formation and characteristics of the biogeochemical interfaces and their effect on organic chemical sorption.

Forschergruppe (FOR) 1525: INUIT - Ice Nuclei research UnIT, Chemische und mineralogische Charakterisierung von Eisnuklei und Eisresiduen

Vorkommen, Häufigkeit, chemische Zusammensetzung und Mischungszustand jener Aerosolpartikel in der Erdatmosphäre, an denen sich durch heterogene Nukleation in unterkühlten Wolken Eis bilden kann (Ice Nucleating Particles = INP), werden experimentell untersucht. Diese Informationen sind wichtig für das Verständnis der Niederschlagsbildung, und finden in parametrisierter Form Eingang in meteorologische Modelle zur Vorhersage des Niederschlages. Das Projekt verwendet hierbei im Wesentlichen physikalische Methoden zur Identifikation und Isolation der Partikel aus der Atmosphäre, und nachfolgend elektronenmikroskopische Methoden zur mineralogischen Analyse einzelner Partikel. Die Identifikation jener wenigen Aerosolpartikel (ca. 1 von 10.000 bis 1 von 100.000), die Eisbildungsfähigkeit besitzen, erfolgt, indem eine Aerosolprobe einer Unterkühlung unter 0°C und Wasserdampfübersättigung ausgesetzt wird, und die an INP entstehenden Eiskristalle fotografiert und gezählt werden. Es werden sowohl Aerosolpartikel aus luftgetragenem Aerosol untersucht (aus dem Eiskeimzähler FINCH) wie auch Partikel, die aus einer Luftprobe auf einem Silizium-Probenträger niedergeschlagen und danach als INP identifiziert wurden (Eiskeimzähler FRIDGE). Eine dritte und vierte Methode (Ice-CVI und ISI) isolieren eisbildungsfähige Partikel, indem aus einer angesaugten Probe von Wolkenluft die Eiskristalle strömungstechnisch von den übrigen Luftbestandteilen getrennt werden. Alle Eiskeimproben werden im Rasterelektronenmikroskop auf Größe, Morphologie, Mischungszustand und chemische Zusammensetzung untersucht und die Ergebnisse der verschiedenen Ansätze verglichen. In Feldexperimenten werden Atmosphärenproben verschiedener geographischer Provenienz (Mitteleuropa, Forschungsstation Jungfraujoch, Wüstenstaub, Vulkanstaub) erhalten. In Laborexperimenten wird mit vorher gesammelt und charakterisierten Modellsubstanzen gearbeitet. Weiterhin wird durch tägliche Messungen der Anzahl-Konzentration und Zusammensetzung von Eiskeimen am Taunus Observatorium nahe Frankfurt über einen längeren Zeitraum untersucht, ob es Saisonalitäten, bevorzugte Quellgebiete (z.B. Wüsten, Industrie, etc.) und biologische Einflussfaktoren (z.B. Pollen, Pflanzenabrieb, Bakterien) für das Vorkommen von Eisnuklei gibt.

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