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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.

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.

Physiologische Reaktionen von Bäumen auf den Klimawandel - Wallis

Pflanzen im Allgemeinen und Bäume im Speziellen reagieren sehr sensibel auf klimatische Veränderungen. Der Kohlenstoff- und Wasserhaushalt wird unter Feldbedingungen gemessen und gibt so Aufschluss über physiologische Regelmechanismen (z.B. zwischen Wasserhaushalt und dem Öffnungsgrad der Stomata) oder das Baumwachstum. Mit Hilfe von systemischen Modellen interpretieren wir die ökophysiologischen Messungen und folgern daraus, wie weit sich einzelne Baumarten an veränderte klimatische Bedingungen anpassen können und ab wann artspezifische physiologische Grenzen erreicht werden. Im Wallis wachsen Waldföhren und Flaumeichen zumindest zeitweise am Rande ihrer physiologischen Möglichkeiten. Erste Resultate zeigen, warum die Flaumeiche (Quercus pubescens) unter den herrschenden klimatischen Bedingungen physiologische Vorteile gegenüber der Waldföhre (Pinus sylvestris) hat.

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) 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, Biogene Opalisotope - neue Proxies zur Untersuchung vergangener Nährstoffkreisläufe und hydrographischer Strukturen im Südpazifik in Beziehung zu der Entwicklung des Klimas und der antarktischen Kryosphäre

Der Verlauf der atmosphärischen CO2-Konzentrationen während der vergangenen Klimazyklen ist durch ein Sägezahnmuster mit Maxima in Warmzeiten und Minima in Kaltzeiten geprägt. Es besteht derzeit Konsens, dass insbesondere der Süd Ozean (SO) eine Schlüsselfunktion bei der Steuerung der CO2-Entwicklung einnimmt. Allerdings sind die dabei wirksamen Mechanismen, die in Zusammenhang mit Änderungen der Windmuster, Ozeanzirkulation, Stratifizierung der Wassersäule, Meereisausdehnung und biologischer Produktion stehen, noch nicht ausreichend bekannt. Daten zur Wirkung dieser Prozesse im Wechsel von Warm- und Kaltzeiten beziehen sich bislang fast ausschließlich auf den atlantischen SO. Um ein umfassendes Bild der Klimasteuerung durch den SO zu erhalten muss geklärt werden, wie weit sich die aus dem atlantischen SO bekannten Prozesswirkungen auf den pazifischen SO übertragen lassen. Dies ist deshalb von Bedeutung, da der pazifische SO den größten Teil des SO einnimmt. Darüber hinaus stellt er das hauptsächliche Abflussgebiet des Westantarktischen Eisschildes (WAIS) in den SO dar. Im Rahmen des Projektes sollen mit einer neu entwickelten Proxy-Methode Paläoumwelt-Zeitreihen an ausgewählten Sedimentkernen von latitudinalen Schnitten über den pazifischen SO hinweg gewonnen werden. Dabei handelt es sich um kombinierte Sauerstoff- und Siliziumisotopenmessungen an gereinigten Diatomeen und Radiolarien. Es sollen erstmalig die physikalischen Eigenschaften und Nährstoffbedingungen in verschiedenen Stockwerken des Oberflächenwassers aus verschiedenen Ablagerungsräumen und während unterschiedlicher Klimabedingungen beschrieben werden. Dies umfasst Bedingungen von kälter als heute (z.B. Letztes Glaziales Maximum) bis zu wärmer als heute (z.B. Marines Isotopen Stadium, MIS 5.5). Die Untersuchungen geben Hinweise zur (1) Sensitivität des antarktischen Ökosystems auf den Eintrag von Mikronährstoffen (Eisendüngung), (2) Oberflächenwasserstratifizierung und (3) 'Silicic-Acid leakage'-Hypothese, und tragen damit zur Überprüfung verschiedener Hypothesen zur Klimawirksamkeit von SO-Prozessen bei. Die neuen Proxies bilden überdies Oberflächen-Salzgehaltsanomalien ab, die Hinweise zur Stabilität des WAIS unter verschiedenen Klimabedingungen geben. Darüber hinaus kann die Hypothese getestet werden, nach der der WAIS während MIS 5.5 vollständig abgebaut war. Die Projektergebnisse sollen mit Simulationen mit einem kombinierten biogeochemischen (Si-Isotope beinhaltenden) Atmosphäre-Ozean-Zirkulations-Modell aus einem laufenden SPP1158-DFG Projekt an der CAU Kiel (PI B. Schneider) verglichen werden. Damit sollen die jeweiligen Beiträge der Ozeanzirkulation und der biologischen Produktion zum CO2-Austausch zwischen Ozean und Atmosphäre getrennt und statistisch analysiert werden. Informationen zu Staubeintrag, biogenen Flussraten, physikalischen Ozeanparametern und zur Erstellung von Altersmodellen stehen durch Zusammenarbeit mit anderen (inter)nationalen Projekten zur Verfügung.

Improving the Livelihood of the Rural Population through the Production of Bushmeat in Ghana

Background: Ghanas transition forests, neighbouring savannahs and timber plantations in the Ashanti region face a constant degradation due to the increased occurrence of fires. In most cases the fires are deliberately set by rural people for hunting purposes. Main target is a cane rat, here called grasscutter (Thryonomys swinderianus), whose bushmeat is highly esteemed throughout the country. The animal is a wild herbivorous rodent of subhumid areas in Africa south of the Sahara. The grasscutter meat is an important source of animal protein. Existing high-value timber plantations (mainly Teak, Tectona grandis) are affected by fires for hunting purposes. Thus resulting in growth reduction, loss of biomass or even complete destruction of the forest stands. It became obvious that solutions had to be sought for the reduction of the fire risk. Objectives: Since 2004 the Institute for World Forestry of the Federal Research Centre for Forestry and Forest Products, Hamburg, Germany is cooperating with a Ghanaian timber plantation company (DuPaul Wood Treatment Ltd.) the German Foundation for Forest Conservation in Africa (Stiftung Walderhaltung in Afrika) and the Center for International Migration with the purpose to improve the livelihood of the rural population in the surroundings of the forest plantation sites and simultaneously to safeguard and improve the timber plantations. The introduction of grasscutter rearing systems to local farmers accompanied by permanent agricultural and agroforestry practices appeared to be a promising approach for the prevention of fires in the susceptible areas. Additionally a functioning grasscutter breeding system could contribute to the improvement of food security, development of income sources and the alleviation of poverty. The following measures are implemented: - Identification of farmers interested in grasscutter captive breeding, - Implementation of training courses for farmers on grasscutter rearing, - Delivery of breeding animals, - Supervision of rearing conditions by project staff, - Development of a local extension service for monitoring activities, - Evaluation of structures for grasscutter meat marketing. Results: After identification of key persons for animal rearing training courses were successfully passed and animals were delivered subsequently. Further investigations will evaluate the effects of the grasscutter rearing in the project region. This will be assessed through the - Acceptance of grasscutter rearing by farmers, - Success of the animal caging, - Reproduction rate, - Meat quality, - Marketing success of meat, - Reduction of fire in the vicinity of the timber plantations, - Improvement of peoples livelihood.

Dynamic (redox) interfaces in soil - Carbon turnover in microbial biomass and flux into soil organic matter

Existing models of soil organic matter (SOM) formation consider plant material as the main source of SOM. Recent results from nuclear magnetic resonance analyses of SOM and from own incubation studies, however, show that microbial residues also contribute to a large extent to SOM formation. Scanning electron microscopy showed that the soil mineral sur-faces are covered by numerous small patchy fragments (100 - 500 nm) deriving from microbial cell wall residues. We will study the formation and fate of these patchy fragments as continuously produced interfaces in artificial soil systems (quartz, montmorillonite, iron oxides, bacteria and carbon sources). We will quantify the relative contributions of different types of soil organisms to patchy fragment formation and elucidate the effect of redox con-ditions and iron mineralogy on the formation and turnover of patchy fragments. The develop-ment of patchy fragments during pedogenesis will be followed by studying soil samples from a chronosequence in the forefield of the retreating Damma glacier. We will characterize chemical and physical properties of the patchy fragments by nanothermal analysis and microscale condensation experiments in an environmental scanning electron microscope. The results will help understanding the processes at and characteristics of biogeochemical interfaces.

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