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Found 786 results.

Forschergruppe (FOR) 986: Structural Change in Agriculture, How should Model Linkages be designed to analyze the Effects of Global Agricultural Trade Liberalization at the Farm Level?

In the last decades agricultural policy has gained increasingly in complexity. Nowadays it influences the food and agricultural sector from the global market down to the farm level. Widespread research questions, like the impact of the WTO negotiations on the farm structure, most often require comprehensive modeling frameworks. Thus, different types of models are utilized according to their comparative advantages and combined in a strategically useful way to more accurately represent micro and macro aspects of the food and agricultural sector. Consequently, in recent years we have seen an increase in the development and application of model linkages. Given this background, the overall objective of this subproject is a systematic sensitivity analysis of model linkages that gradually involves more and more characteristics of the linkage and the corresponding transfer of results between models. In addition, the project aims to answer the following specific question: How does structural change at the farm level influence aggregate supply and technical progress? Under which conditions is it possible to derive macro-relationships from micro-relationships? How does the aggregation level influence the model results and how can possible problems be overcome? This procedure is used to quantify the effects and to derive conditions for optimal interaction of the connected models. The analysis is based on the general equilibrium model GTAP (Global Trade Analysis Project) and the farm group model FARMIS (Farm Modelling Information System) which are employed in conjunction to analyze the effects of WTO negotiations on the farm level.

Technical Support for the revision of ecolabel and green public procurement GPP Criteria Lot 1

The project's objective is to support JRC IPTS in revising the existing Ecolabel and GPP criteria of personal computers and notebook computers. The priority in this revision process is to first analyse which of the existing criteria and the supporting evidence are still valid and to identify the additional research that should be carried out. Potential additional criteria can be developed, if identified as necessary in the course of the study. The study starts with a definition of the scope; the necessarity for new or revised Ecolabel and GPP criteria is based on a market analysis and a technical analysis with research on the most significant environmental impacts during the whole life cycle of the products. This also includes the application of a consistent methodological approach regarding the hazardous substances criteria. Based on these findings, the improvement potential will be derived resulting in a proposal for a revised Ecolabel and GPP criteria set for desktop and notebook computers which will be discussed in a European stakeholder process.

A behavioural economic analysis of moral hazards in food production: the case of deviant economic behaviour and disclosure policies on the restaurant, ready-to-eat and retail level

Deviant behaviour on various levels of the food supply chain may cause food risks. It entails irregular technological procedures which cause (increased probabilities of) adverse outcomes for buyers and consumers. Besides technological hazards and hitherto unknown health threats, moral hazard and malpractice in food businesses represent an additional source of risk which can be termed 'behavioural food risk'. From a regulatory perspective, adverse outcomes associated with deviance represent negative externalities that are caused by the breaking of rules designed to prevent them. From a rational choice perspective, the probability of malpractice increases with the benefits for its authors. It decreases with the probability of detection and resulting losses. It also decreases with bonds to social norms that protect producers from yielding to economic temptations. The design of mechanisms that reduce behavioural risks and prevent malpractice requires an understanding of why food businesses obey or do not obey the rules. This project aims to contribute to a better understanding of malpractice on the restaurant/retail level through comparative case studies and statistical analyses of food inspection and survey data. Accounting for the complexity of economic behaviour, we will not only look at economic incentives but consider all relevant behavioural determinants, including social context factors.

Biogenic formation of non-extractable residues from pesticides in soil

During microbial turnover of organic chemicals in soil, non-extractable residues (NER) are formed frequently. Studies on NER formation usually performed with radioisotope labelled tracer compounds are limited to localisation and quantitative analyses but their chemical composition is left unknown. Recently, we could show for 2,4-dichlorophenoxyacetic acid and ibuprofen that during microbial turnover in soil nearly all NER were derived from microbial biomass, since degrading bacteria use the pollutant carbon for their biomass synthesis. Their cell debris is subsequently stabilised within soil organic matter (SOM) forming biogenic NER (bioNER). It is still unknown whether bioNER are also formed during biodegradation of other, structurally different compound classes of organic contaminants. Therefore, agricultural soil will be incubated with labelled compounds of five classes of commonly used and emerging pesticides: organophosphate, phenylurea, triazinone, benzothiadiazine and aryloxyphenoxypropionic acid. The fate of the label will be monitored in both living and non-living SOM pools and the formation of bioNER will be quantified for each compound over extended periods of time. In addition, soil samples from long-term lysimeter studies with 14C-labelled pesticide residues (e.g. triazine, benzothiazole and phenoxypropionic acid group) will be also analysed for bioNER formation. The results will be summarised to identify the metabolic conditions of microorganisms needed for bioNER formation and to develop an extended concept of risk assessment including bioNER formation in soils.

Simulated field environment with combined salt and drought stresses as a platform for phenotyping plant tolerance to salinity

Salinity occurs often simultaneously with drought stress. Therefore, breeding for tolerance to combined both stresses can contribute significantly to crop yield. However, classical selection in salinity has generally been unsuccessful, partly due to high variability of salt stress resulting from the different salinity and drought status. Unfortunately, the use of unrealistic stress protocols for mimicking salinity and drought stress is the norm rather than the exception in biotechnological studies. Therefore, the great challenge is to gain knowledge required to develop plants with enhanced tolerance to field conditions. Our overall hypothesis is that a realistic stress protocol simulating a field environment with combined salt and drought stress as a platform for precision phenotyping of plant tolerance to salinity may solve this problem. This study will demonstrate that highly managed stress environments can be created and key traits of plants can be characterised by using advanced non-destructive sensors that are able to identify relevant traits of plants.

Forschergruppe (FOR) 1525: INUIT - Ice Nuclei research UnIT, In-situ Messungen von eiskeimbildenden Partikeln (INP) und quantitative Bestimmung von biologischen INP

Die Bildung der Eis Phase in der Troposphäre stellt einen wichtigen Fokus der aktuellen Atmosphärenforschung dar. Durch heterogene Nukleation entstehen bei Temperaturen oberhalb von -37°C primäre Eiskristalle an sogenannten eiskeimbildenden Partikeln (INP, engl, ice nucleating particles). Die räumliche Verteilung der INP und deren Quellen variieren stark. In der Atmosphäre finden sich INP nur in sehr geringer Anzahlkonzentration, oft weniger als ein Partikel pro Liter, und sie stellen nur eine kleine Untergruppe des gesamten atmosphärischen Aerosols dar. Ziel dieses Antrages ist es die Anzahlkonzentrationen von eiskeimbildenden Partikeln und deren Variabilität in der Atmosphäre zu messen. Außerdem sind Laborstudien geplant, in denen unser Verständnis über die chemischen und biologischen Eigenschaften der Partikel, die die Eisbildung initiieren, verbessert werden soll. Mit dem von unserer Arbeitsgruppe entwickelten Eiskeimzahler FINCH (Fast Ice Nucleaus CHamber) sollen die atmosphärischen Anzahlkonzentrationen von INP bei verschiedenen Gefriertemperaturen und Übersättigungen an mehreren Standorten gemessen werden. Die Kopplung von FINCH mit einem virtuellen Gegenstromimpaktor (CVI, engl, counter-flow virtual impactor, Kooperation mit RP2), die während lNUIT-1 entwickelt und getestet wurde, soll nun weiter charakterisiert und Messungen damit fortgesetzt werden. Bei dieser Methode werden die Eispartikel, die in FINCH gebildet werden, von den unterkühlten Tröpfchen und inaktivierten Partikeln separiert und mit weiteren Messmethoden untersucht. In Kooperation mit RP2 und RP8 planen wir hierbei die Charakterisierung der INP mittels Größen- und Aerosolmassenspektrometer sowie die Sammlung der INP auf Filtern oder Impaktorplatten zur anschließenden Analyse mit einem Elektronenmikroskop (ESEM, engl. DFG fomi 54.011 -04/14 page 3 of 6 Environmental Scanning Electron Microscopy). Die Feldmessdaten werden von umfangreichen Laborstudien an den Forschungseinrichtungen AIDA (RP6) und LACIS (RP7) ergänzt. Dort soll das Immersionsgefrieren von verschiedenen Testpartikeln aus biologischem Material (z.B. Zellulose), porösem Material (z.B. Zeolith) und Mineralstaub mit geringem organischem Anteil im Detail untersucht werden. Des Weiteren planen wir Labormessungen, bei denen eine verbesserte Charakterisierung der Messunsicherheiten von FINCH erarbeitet werden soll. Außerdem werden regelmäßige Tests und Kalibrierungen mit FINCH durchgeführt, für die Standardroutinen festgelegt werden sollen. Um die Rolle der INP bei der Wolken- und Niederschlagsbildung sowie bei den Wolkeneigenschaften abzuschätzen, werden die gewonnenen Messergebnisse am Ende als Eingabeparameter für erweiterte Wolkenmodelle (Kooperation mit WP-M) dienen.

Contribution of ectomycorrhizal fungi to the formation and mobilization of soil organic matter (SOM)

In forest ecosystems ectomycorrhizal fungi are responsible for the mobilization of mineral nutrients from soil organic matter (SOM) resulting in a marked increase in productivity of their symbiotic host plants. In return the fungi obtain a significant amount of photosynthetic products from these plants, allowing the formation of an extensive hyphal system. These hyphae constitute a major part of soil biomass and, ultimately, a major source for SOM formation. While plant-fungal nutrient exchange has been analyzed extensively, this proposal is focused on the fungal contribution to SOM formation and on the processes leading to the acquisition of nutrients by the fungi. These two processes will be studied separately and in a quantitative way using isotopic labeling in soil bioreactors. Analysis of the fate of 13C labeled fungal material (Laccaria bicolor) in soil bioreactors will tell how fast and to what extent the various fractions of hyphal biomass are transformed into non-living SOM. As potential molecular or structural markers for SOM formation from fungal hyphae we will analyze characteristic remnants of fungal hyphae in SOM using scanning electron microscopy, DNAfragments using a PCR approach for the fungal rRNA internal transcribed spacerregions and biochemical markers like fatty acids and ergosterol. The impact of ectomycorrhizal mycelia supported by Pinus sylvestris plantlets on 13C- and 15N-labeled SOM and on microbial biomass will be analyzed in separate soil bioreactor experiments.

Energiemanagement für Supercap-Brennstoffzellenfahrzeuge

Eine Brennstoffzelle als Primärenergiequelle mit einem Doppelschichtkondensator (Supercap) als Zwischenspeicher zu kombinieren ist ein vielversprechender Ansatz für zukünftige Elektrofahrzeuge. In Kooperation mit einem Fahrzeughersteller wurden verschiedene Strategien für ein Energiemanagement für die Kombination einer Brennstoffzelle mit einem Doppelschichtkondensatormodul entworfen und verglichen. Basierend auf der aktuellen Geschwindigkeit und Beschleunigung werden verschiedene Fahrzeugzustände bezüglich kinetischer Energie und Leistungsbedarf unterschieden. In Abhängigkeit von der verfügbaren Leistung von Supercaps und Brennstoffzelle wird eine optimale Leistungsaufteilung zwischen den beiden Energiequellen ermittelt. In Bremsphasen wird durch Rekuperation Energie zurückgewonnen und in den Supercaps gespeichert. Wenn die Supercaps vollgeladen sind oder ihre maximale Ladeleistung erreicht haben, übernehmen mechanische Bremsen die übrige Ladeleistung. Da diese Situation zu einem Energieverlust führt, sollte sie möglichst vermieden werden. Um immer die notwendige Beschleunigungsleistung und gleichzeitig auch ein Maximum an Rekuperation zu garantieren, wird der Ladezustand der Supercaps kontinuierlich und dynamisch an die kinetische Energie des Fahrzeugs angepasst. Verschiedene Strategien wurden in Matlab/Simulink mit einem Stateflow-Chart zur Abbildung der Zustände implementiert. Die verfügbare Supercapleistung wird mit Hilfe eines impedanzbasierten Modells für Supercaps berechnet. Mit diesen Strategiemodellen können die Leistungsfähigkeit der verschiedenen Strategien verglichen und die Einflüsse von Parametern untersucht werden. Ziel eines Energiemanagements ist es, den Wasserstoffverbrauch zu minimieren und die notwendige Leistung zu jeder Zeit sicherzustellen. Bei der Bewertung der Strategien wird der Wasserstoffverbrauch, die verlorene Bremsenergie und eine mögliche Geschwindigkeitsreduzierung verglichen. Mit einer optimalen Strategie können bis zu 23 Prozent Wasserstoff während eines definierten Fahrprofils gespart werden.

Biogenic soil structures: feedbacks between bioactivity and spatial heterogeneity of water storage and fluxes from plot to hillslope scale

Soil structure determines a large part of the spatial heterogeneity in water storage and fluxes from the plot to the hillslope scale. In recent decades important progress in hydrological research has been achieved by including soil structure in hydrological models. One of the main problems herein remains the difficulty of measuring soil structure and quantifying its influence on hydrological processes. As soil structure is very often of biogenic origin (macropores), the main objective of this project is to use the influence of bioactivity and resulting soil structures to describe and support modelling of hydrological processes at different scales. Therefore, local scale bioactivity will be linked to local infiltration patterns under varying catchment conditions. At hillslope scale, the spatial distribution of bioactivity patterns will be linked to connectivity of subsurface structures to explain subsurface stormflow generation. Then we will apply species distribution modelling of key organisms in order to extrapolate the gained knowledge to the catchment scale. As on one hand, bioactivity influences the hydrological processes, but on the other hand the species distribution also depends on soil moisture contents, including the feedbacks between bioactivity and soil hydrology is pivotal for getting reliable predictions of catchment scale hydrological behavior under land use change and climate change.

Fragmentation of the international forest regime complex: multi-dimensional descriptions, explanations, steering consequences and polital options; The production and utilisation of forest regime fragmentation by bureaucratic politics

This project aims at analysing the influence of competing national and international bureaucracies on the fragmentation of the international forest regime complex (IFRC). Its objectives are: - describing the political dimension of fragmentation of the IFRC programme- explaining the political dimension of fragmentation based on the model of bureaucratic politics- analysing the steering consequences resulting from fragmentation - trans-disciplinary design of solutions for coping with political aspects of fragmentationBuilding on the bureaucratic politics approach these objectives will be pursued by testing the linking hypothesis: Interest and influence of the bureaucracies cause a fragmented programme of the IFRC. This programme supports the goal of profitable timber production but keeps the decision about biodiversity and CO2 sequestration open hindering the effective steering by the IFRC. The project develops an analytical framework consisting of the following independent variables: competing national and competing international bureaucracies, elected politicians, national and international non-state actors and media discourses. The fragmentation of the political programme of the IFRC is the overall dependent variable. This project will analyse the influence of bureaucracies and their coalitions on fragmentation at the international level as well as in national case studies in Sweden, Poland and Germany. The other independent variables will be covered by sub-projects 2, 3 and 4. The findings will be linked to the other political and to the economic and technic-ecological sub projects in order to contribute to the multi-disciplinary description and explanation of fragmentation and its steering consequences.

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