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Found 109 results.

Uncertainty and the bioeconomics of near-natural silviculture

Research in 'silviculture' and 'forest economics' very often takes place largely independent from each other. While silviculture predominantly focuses on ecological aspects, forest eco-nomics is sometimes very theoretic. The applied bioeconomic models often lack biological realism. Investigating mixed forests this proposal tries to improve bioeconomic modelling and optimisation under uncertainty. The hypothesis is tested whether or not bioeconomic model-ling of interacting tree species and risk integration would implicitly lead to close-to-nature forestry. In a first part, economic consequences of interdependent tree species mixed at the stand level are modelled. This part is based on published literature, an improved model of timber quality and existing data on salvage harvests. A model of survival over age is then to be developed for mixed stands. A second section then builds upon data generated in part one and concentrates on the simultaneous optimisation of species proportions and harvest-ing ages. It starts with a mean-variance optimisation as a reference solution. The obtained results are compared with data from alternative approaches as stochastic dominance, down-side risk and information-gap robustness.

Human influences on forests in southern Ethiopia: the case of Shashemane-Munessa-forest

Especially during the last decades, the natural forests of Ethiopia have been heavily disturbed by human activities. Some forests have been totally cleared and converted into fields for agricultural use, other suffered from different influences, such as heavy grazing and selective logging. The ongoing research in the Shashemane-Munessa-study area (Gu 406/8-1,2) showed clearly that, in spite of interdiction and control, forests continue to be cleared and degraded. However, it is not yet sufficiently known, how and why these processes are still going on. Growing population pressure and economic constraints for the people living in and around the forests contribute to the actual situation but allow no final answers to the complex situation. Concerning a sustainable management of the forests there is to no solid basis for recommendations from the socioeconomic and socio-cultural view. Therefore, a comprehensive analysis of the traditional needs and forms of forest use, including all forest products, is necessary. The objective of this project is, to achieve this basis by carrying out intensive field observations, the consultation of aerial photographs, satellite imagery and above all semi-structured interviews with the population in the study area in order to contribute to the recommendations for a sustainable use of the Munessa Shasemane forests.

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.

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.

Environmental and economic evaluation of the accelerated replacement of domestic appliances. Case study refrigerators and freezers

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.

Agricultural Entrepreneurs' Decision Making and Structural Change: An Experimental Approach

The rational calculus of farmers assumed in many agricultural economic models is unrealistic and non-predictive of their actual decision making. Understanding structural change in agriculture can thus be improved via a realistic modeling of the decision making by agricultural entrepreneurs. Specifically, slow disinvestment (i.e., postponing farm exit), persistence of market structures (i.e., failure to reallocate land plots towards higher efficiency), and more generally characterizing the decision making of farmers are crucial for a better understanding of structural change and policy advice. We apply economic experiments to better understand such disinvestment choices, land markets with economies of scale and private opportunity costs, different auction and bargaining forms to improve allocation efficiency of land markets, and to generally characterize the decision making of farmers.

MYFISH - Maximising yield of fisheries while balancing ecosystem, economic and social concerns

The MSY concept was included as a principle in the 2009 Green Paper on the reform of the Common Fisheries Policy (CFP) in accordance with the global imperative to manage fish stocks according to the maximum sustainable yield (MSY). This implies a commitment to direct management of fish stocks towards achieving MSY by 2015. Attaining this goal is complicated by the lack of common agreement on the interpretation of 'sustainability' and 'yield' and by the effects that achieving MSY for one stock may have on other stocks and broader ecosystem, economic, or social aspects. MYFISH will provide definitions of MSY variants which maximize other measures of 'yield' than biomass and which account for the fact that single species rarely exist in isolation. Further, MYFISH will redefine the term 'sustainable' to signify that Good Environmental Status (MSFD) is achieved and economically and socially unacceptable situations are avoided, all with acceptable levels of risk. In short, MYFISH aims at integrating the MSY concept with the overarching principals of the CFP: the precautionary and the ecosystem approach. MYFISH will achieve this objective through addressing fisheries in all RAC areas and integrating stakeholders (the fishing industry, NGOs and managers) throughout the project. Existing ecosystem and fisheries models will be modified to perform maximization of stakeholder approved yield measures while ensuring acceptable impact levels on ecosystem, economic and social aspects. Implementation plans are proposed and social aspects addressed through active involvement of stakeholders. Finally, effects of changes in environment, economy and society on MSY variants are considered, aiming at procedures rendering the MSY approach robust to such changes. The expertise of 26 partners from relevant disciplines including fisheries, ecosystem, economic and social science are involved in all aspects of the project. Global experience is engaged from North America and the South Pacific.

Balancing regulating and provisioning ecosystem services: Comprehensive land-use concepts for effective conservation

A growing trend to produce fuel ethanol from grain and continuing changes in human diets, as observed with increasing standard of living, have led to increasing land-use conflicts. The observable high food prices are - at least in part - a consequence of the above development. They act as signals to increase production, often combined with severe environmental problems. Moreover, as another obviously undesirable consequence, high prices may reduce consumption, particularly among the world's poor. Achieving sustainable land use by means of an optimal allocation of scarce land resources to competing purposes is thus a major global challenge for the 21st century. The results of this work are supposed to be transferred to the dry forest region around the Laipuna Reserve (Ecuador). We will couple several land-use models and modelling approaches, all built on economic drivers (economic risk and return of land-use options), to conceptualise a land-use model and to develop land-use scenarios for the study area at landscape level. The existing land-use approaches will be coupled for this task and expanded by dietary energy and fuel energy outputs and by consequences of land-use scenarios for carbon pools and water protection. The available models, such as 'Ecological-Economic Farm Diversification' (dynamic farm-level perspective), 'Optimized Land-Use Diversification' (comparative-static national level approach) and 'Compartmental land-use approaches' (dynamic farm/landscape-level, so far scenario based), address various scales. It is intended to combine them by means of modelling various farm types which are representative for a specific area. Land-use scenarios include various food price projections and scenarios on vulnerability of production systems. The hypothesis to be tested is: 'Increasing the production of food, biofuel and timber by appropriate landscape concepts for intensification and/or recultivation of abandoned lands reverses the adverse effects of indirect land-use change: Such strategies lead to more efficient land allocation and to decreasing prices, thus mitigating the pressure on forest ecosystems to reduce the costs of conservation strategies and those of providing regulating services.

Sonderforschungsbereich (SFB) 564: Nachhaltige Landnutzung und ländliche Entwicklung in Bergregionen Südostasiens; Sustainable Land Use and Rural Development in Mountainous Regions of Southeast Asia, E 1.2: Multi-layer drying models for optimising high value crop drying in small scale food industries

Fruit tree cultivation is a suitable option for erosion control in mountainous regions of Southeast Asia. However, seasonal overproduction and insufficient access to markets can cause economic losses. The possibility of processing fruits locally could contribute considerably to increase and stabilize farm income. Currently, fruit drying methods in these areas are yielding products of inferior quality. Pre-treatments such as sulphurizing are commonly used, but can make the product undesirable for international markets. In addition, high energy requirements increase production costs significantly. Therefore, the objective of subproject E1.2 is to optimize the drying process of small-scale fruit processing industries in terms of dryer capacity, energy consumption and efficiency and end product quality. During SFB-phase II in E1.1, drying fundamentals for the key fruits mango, litchi and longan were established. In laboratory experiments, impacts of drying parameters on quality were investigated and numerical single-layer models for simulation of drying kinetics have been designed. In SFB-phase III this knowledge will be expanded with the aim of optimizing practical drying processes. Therefore, the single-layer models will be extended to multi-layer models for simulating bulk-drying conditions. The Finite Element Method (FEM) will be adapted to calculate heat and mass transfer processes. Thermodynamic behavior of batch and tray dryers will be simulated using Computational Fluid Dynamics (CFD) software. Drying facilities will be optimized by systematic parameter variation. For reduction of energy costs, the potential of solar energy and biomass will be investigated in particular. Further research approaches are resulting from cooperation with other subprojects. A mechanic-enzymatic peeling method will be jointly used with E2.3 for studying the drying behavior of peeled litchi and longan fruits. Furthermore, a fruit maturity sensor based on Acoustic Resonance Spectroscopy (ARS) will be developed in cooperation with E2.3 and B3.2. Finally, an internet platform will be built for exchange of farmer-processor information about harvest time and quantities to increase utilization of the processing facilities.

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