Institut für Landwirtschaftliche Betriebslehre
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Publication Prozess der Transformation der Landwirtschaft Usbekistans und Probleme bei der Umstrukturierung der landwirtschaftlichen Betriebe(2002) Nazarkulov, Umidjan Rakhimjanovich; Zeddies, JürgenPrivatization of agricultural enterprises in former soviet countries has led to changes in production structure, methods of production and management of enterprises. Hence, the main objective of this dissertation is, at first, analysis of development of the agrarian sector and agricultural enterprises on the example of the Republic of Uzbekistan, and the identification of their weaknesses and problems. Furthermore aspects of management and marketing are considered and recommendations on improving the strategy of optimization the production process, which will serve as a basis for decision-making in the appropriate organizations. The structural changes in typical farms of 3 regions of the Republic of Uzbekistan under different frame conditions are analyzed using a linear programming model. The results of these optimization calculations are leading to the following requirements: - Change of the production structure and reduction of the state influence and governmental control; - Cancellation of fixed state prices of cotton and wheat with a simultaneous increase of water taxes; - Reduction of labour input and increase of wages with the purpose of improving the motivation and efficiency of labour; - Extension of the area of family farms. According to the model calculations a liberalisation of agricultural markets would lead to the following consequences for farm enterprises and agricultural production: - A substantial reduction of cotton production will lead to a wider crop rotation and better soil fertility; - The total gross margins of the farm enterprises will increase due to an optimization of production and marketing structure; - If the fixed producer prices for wheat and cotton will be eliminated, wheat production would increase significantly; - Depending on the region animal stocks will show a different development pattern. While in one region the big farms will reduce their livestock production, in two other regions they will be increased. Family farms tend to reduce the livestock number due to scarcity of land resources; - Farm incomes can be increased by reducing the number of workers; simultaneously increasing wages and introducing better labour management practices thus contributing to higher motivation and business success; - Profits should be invested in new machinery and equipment in order to maintain adequate levels of production; - Private family farms show a relatively high labour capacity and would be able to increase their farm land. Therefore liberalization of land market is necessary; - For family farms a liberalization of producer prices will lead to similar changes in production and marketing structures as for big farm enterprises. In conclusion it can be recommended to state institutions to reduce their influence on the operational decisions of farmers. The main objective of agricultural policy in future should be improvement of frame conditions for trade, liberalization of markets, effective support to structural changes and creation of a system of social support to farmers.Publication Biogenic Greenhouse Gas Emissions from Agriculture in Europe - Quantification and Mitigation(2002) Freibauer, Annette; Zeddies, JürgenThis dissertation analyses relevant potential mitigation strategies of biogenic greenhouse gases (GHGs) in the agriculture of the European Union (EU) in light of the Kyoto Protocol. It identifies where important sources and mitigation potentials are located and what uncertainty, environmental ancillary effects and costs are associated with them. Literature reviews are performed and methodologies for environmental assessment and GHG accounting are further developed. On this basis, GHG emissions are quantified and reduction potentials are assessed at European level. In 1995, European agriculture emitted 0.84 ± 0.29 Tg N2O, 8.1 ± 1.9 Tg methane (CH4) and 39 Tg ± 25 carbon dioxide (CO2), which adds up to 470 ± 80 Tg CO2-equivalents or 11% of the overall anthropogenic greenhouse gas emissions of the EU. The detailed methodology developed here adequately resolves regional specifics of agricultural conditions and reduces the methodological uncertainty in the estimates to half of the one in the official national inventories. European agricultural soils will at maximum sequester carbon in the order of 100 Tg a-1 CO2 over the coming years, which may also provide other environmental benefits. The biological potential of bioenergy in the EU allows to substitute for 400 to 800 Tg a-1 CO2-equivalents. From an environmental perspective, the use of perennials, especially of residues and woody biomass, is preferable to intensively grown annual crops. The biological potential for technical GHG reduction measures in EU agriculture is between 100 and 200 Tg a-1 CO2-equivalents. Promising measures promote the extensivation of arable cropping by reducing nitrogen inputs, technological innovation in animal husbandry, which is best accompanied by a further decline in animal numbers, as well as rewetting drained organic soils. Most measures will provide ancillary environmental benefits. Changing the socio-economic and political frame conditions may enhance the GHG mitigation potential.Publication Regionale Darstellung der Umweltbelastungen durch klimarelevante Gase in der Agrarlandschaft Kraichgau - Das Boden-Landnutzungs-Informations-System für Treibhausgasemissionen(2003) Rohierse, Andrea; Doluschitz, ReinerSummary Goals The goals of the doctoral thesis were to determine at regional level the environmental impacts in the form of greenhouse gas emissions from the agricultural landscape of the Kraichgau region, to produce a method for projecting greenhouse gas emissions from agriculture and to subject appropriate prevention scenarios to an impact analysis. To attain these goals, a geographic information system (GIS) was used to build an environmental information system for greenhouse gases titled ?Soil and Land Use Information System for Greenhouse Gas Emissions?. Results Spatial presentation of the geodata bank Besides generation of a map of potential soil moisture for the Kraichgau region, the geodata basis developed here can be used to produce numerous thematic maps, such as fertilization maps and emissions maps of the greenhouse gases nitrous oxide and methane, as well as a map of the CO2 equivalent inventory. This can visualize the locations of centres of high or low emissions in the Kraichgau region. The findings of the evaluation of land-use maps generated from satellite images of the year 2000 show that the method of supervised classification used there and the multitemporal satellite image evaluation provide sufficient accuracy for a regional determination of greenhouse gas emissions from agriculture, as they were on average able to classify correctly 72% of arable land uses typical of the Kraichgau region. Forecast projection of greenhouse gas emissions from agriculture The environmental information system thus established allowed spatial quantification of Kraichgau-specific emissions. For this physiographic region, average total nitrous oxide emissions of 3.2 kg N2O-N / ha*a according to IPCC (2000b) were determined, taking the 22 Kraichgau municipalities into consideration. The average calculated maximum nitrous oxide emission potential from agriculturally utilized soils of the 2000 reference system at municipal level figures 4.1 kg N2O-N / ha*a, while the minimum figures 2.2 kg N2O-N / ha*a. Using Global Warming Potential (GWP) indexes, the CO2 equivalent inventory was calculated according to IPCC (2001) for the soils of the Kraichgau region. This was found to average 1.5 t CO2 equivalent / ha*a (GWP 100). The knowledge-based approach yielded a CO2 equivalent inventory around 1.1 t CO2 equivalent / ha*a (GWP 100). Overall, modelling found the Kraichgau physiographic region and arable farming region to represent a source of greenhouse gases. This was determined strongly by the high GWP of nitrous oxide compared to that of methane and carbon dioxide, and the circumstance that nitrogen inputs are relatively high in the intensively managed agricultural landscape. Impact analysis The results of the impact analysis show that if total nitrogen inputs are reduced by 20%, then some 6% of greenhouse gas emissions can be saved. If then, in land management, current fertilization guidance such as provided by the nitrate information service is complied with, this resulted in the GIS model in a roughly 10% reduction of CO2 equivalent emissions for the Kraichgau region. In a further prevention scenario, land uses were changed from intensively cultivated field crops (root crops) to extensively cultivated field crops or summer crops (malting barley), these being representative of other extensively cultivated crop varieties. At the same time, arable land was converted to low-intensity grassland areas, preferentially in zone III water protection zones. This reduced the CO2 equivalent inventory in the soil and land use system by about one third. Implementation of further measures and conversion of agriculturally utilized areas to organic management ? which, besides different fertilization practices, involves different cropping structures, a shift from short rotations to multiple rotations, and extensive grassland use ? even produce a reduction of greenhouse gas emissions by about two thirds in the model. The prevention scenarios ? involving reduced nitrogen inputs, compliance with current fertilization guidance across the whole region, and a range of land-use changes through to the conversion of farming practices to organic management ? show that climate protection goals can indeed be achieved in agriculture. This necessitates, besides reducing mineral as well as organic fertilizer inputs, changes in cropping structures, in rotations, in the choice of field crops as well as general changes to management methods and land-use changes. If this package of measures developed in the prevention scenarios were implemented in the production practices of farm holdings, with specific focuses depending upon the specific type of holding, climate protection in agriculture could be promoted greatly.Publication Funktion der föderalen und regionalen Getreidefonds und deren Bedeutung unter marktwirtschaftlichen Verhältnissen(2003) Andrianov, Vladislav; Zeddies, JürgenIn the work is discussed the formation of a Russian grain sector on the ground of analysis of its structure development during the last two centuries, empirical research for activity of state grain funds on federal and regional levels and grain producers in Bryansk oblast. The dynamic planning is used as well to learn more about the development of producers in the region. The goal of the work is to identify an economic effect coming from various instruments, which are used by the state regulating grain production on the both levels and to make recommendations to the influence and organization of the grain policy in Russia. The work is mainly based on statistics from grain producers and Goskomstat in Bryansk oblast. Furthermore common statistics and a professional literature dedicated to the problems of development of Russian grain markets and to state intervention in the market have been evaluated. Based on empirical statistics from grain producers and normative information from Russian research institutes a simultaneous dynamic model has been worked out to make business planning. After this case scenarios showing the development of producers in the region have been developed and the middle-term planning for a period of three years carried out. With the aid of this planning the development chances of agricultural enterprises under present and alternative basic conditions of regional grain policy are analyzed and existing restraints of business are reviewed. In the middle of the 19th century Russia had a significant impact on the world grain market. At that time the country controlled a high market share for wheat, rye, barley and oat. The development of a railroad during this period caused the regional price differences to be settled and the grain production to be expanded into new regions. The grain crops in Russia grew near the crops in the USA and Europe gradually. Running grain bourses bettered the market transparency and boosted the formation of functioning markets in the country. The October revolution slowed down the integration of Russian grain market into world market. During the former Soviet Union Russian grain producers have been separated from the development trends on the world market. The grain export has been controlled by the state. Only the state could export the grain and income from export trade flowed into the federal budget. Collectivization of the soviet agriculture and outbreak of the Second World War contributed to a growing backwardness of the Russian grain sector. That was reflected in a lower level of grain production in Russia. Grain enterprises had any incentives to produce the competitive products which could be sold on the world market. In January 1992 the government monopoly on trade with most agricultural products has been abolished. This caused an increase in the price level of the food on domestic markets. The government constrained the price increase by some basic products like bread and milk but the price control for them has been moved to the area of responsibility of regional authorities. As a result of that there is a wide palette of state instruments at present, which are used for regulation of local grain markets.Publication Entwicklung eines GIS-gestützten schlagbezogenen Führungsinformationssystems für die Zuckerwirtschaft(2005) Laudien, Rainer; Doluschitz, ReinerThe European Union aspires the GIS-based documentation of every agricultural area under cultivation from the year 2005 onwards. With this in mind, this thesis aims to design and develop a user-friendly Management Information System (MIS) for the sugar beet industry, which processes, visualizes, archives and documents geographical, remote sensing and attribute data. To meet the EU requirements the design of this "'Sugar beet Management Information System"' (SuMIS) is targeted at a GIS-based, modular, field-based approach which reflects the whole sugar beet supply chain. Therefore, the user of SuMIS will be able to geo-track and -trace every step from soil sampling to the beet delivery (fff = "from farm to factory"). By including and integrating GIS- and remote sensing data, SuMIS is a comprehensive System which can also be used as a Decision Support System within the Supply Chain Management. Due to the modular process-oriented design of SuMIS the potential of the system can be used by different users of the Supply Chain e.g. the field based documentation on the part of the farmer or the GIS-based decision making on the part of the sugar company. The design of SuMIS is based on the geo-datasets of two areas under investigation: Gemmingen/Kraichgau (area 1) and Plattling/Niederbayern (area 2). The dataset of area 1 represents the main part of the relational SuMIS geo-database and includes operational and external geo-data. The sugar beets in this area do not show plant diseases in general. Therefore, multi- and hyperspectral reflectance data of selected fields of area 2 is used to detect biotic growth-anomalies, general stress indicators and differences concerning plant vitalities and to create the respective spatial cognition. In order to collect the field data, a hyperspectral spectroradiometer (FieldSpec Handheld) is mounted stationary on a developed measurement device. This data is stored in a HTML-based spectral library. Besides that, multitemporal tractor- and airborne hyperspectral spectroradiometer measurements (GVIS, AVIS) are included to validate the ground based data. The reflection measurements are utilized to differentiate between healthy and unhealthy plants by using multispectral and hyperspectral vegetation indices. SuMIS includes new components which are developed and embedded by using the developer software "'Visual Basic"'. These are combined with existing functionalities in order to meet the EU GIS-requirements. Beside the functionalities which are used to analyze the hyperspectral data, two land-use classification methods are presented, applied and compared. Therefore, an object oriented (by using ERDAS Imagine® and a pixel based approach (by using eCognition) is employed to differentiate sugar beets from other crops in a simple and time efficient manner. QuickBird high resolution satellite form the basis for the accurate land use map. By applying the SuMIS functionalities and tools presented in this thesis, the users will be able to digitize their field data without any knowledge about GIS or geo-databases. Furthermore, storing and visualizing alphanumeric geodata is also possible by using these tools. Because of the information-specific structure of the geodata and its storage in several information layers, SuMIS is able to generate for instance mathematic calculations, clip-, merge- and join-procedures. This can be used for the spatial analysis or for creating new information layers. In this thesis such spatial GIS-results are shown in the context of a case study. The results of this case study indicate that the approaches developed lead to plausible results. Besides the description of the design of SuMIS and it's functionalities, the acceptance and survey of the expected individual benefits by potential selected users has been tested. Concerning the utility and value of SuMIS for the sugar beet industry, the functionalities are evaluated. The investigated results are discussed and perspectives for a broad application are described.Publication Ein Nichtlineares Prozessanalytisches Agrarsektormodell für das Einzugsgebiet der Oberen Donau(2005) Winter, Thomas; Dabbert, StephanThis dissertation describes a regionalised non-linear agricultural sector model for the upper danube catchment area. The model is used for simulating and forecasting the impacts of different policies measures and of climate change on farming. The most important task of this model is to fit as a part into the decision-support-system Glowa-Danubia. The main idea of the decision-support-system is, that the impact of the Global-climate change to the water on the upper danubia basin can be shown. At first the interactions between agriculture and water are defined. One of the results is that agriculture is an economic sector, which has an important influence on the water-household of the landscape. Many agricultural activities, e.g. tillage, fertilisation, plant-protection have a direct or indirect impact on the waterhousehold. Of course there are some conflicts with other users of the water resource. In consequence a lot of laws guarantee the safety of the water resources. The farmers are bound by law to practice the so called ?good agricultural practice?. Another possibility for policy to influence farmers is that farmers can take part in agri-environmental programs. In the second chapter the connections between the agricultural sector model and the other models are defined. A division of the agricultural sector model into three main modules is necessary, that the dates can be transferred automatically. The three modules of the agriculture sector model can be overwritten with data resources, model equations and result tables. A process-analytical optimisation model was used, because with this methodological approach the use of fertiliser and other farm inputs and the level of production can be simulated. In the plant production 19 different crop production activities with two different intensities were defined. The production level of each crop was defined by using expert interviews with a Probit-Model. The Probit-Model calculates independ of the ?Landwirtschaftliche Vergleichszahl? (a relative number, which indicates the agronomy quality of soils) in order to define the extent of both intensities. In the animal production 15 different production systems are defined. The constraints and the calibration of the non-linear gross margin function are discussed after the definition of the production activities. Some constraints, for example the crop rotation constraint, are not necessary in the non-linear model. The reference situation is the year 1995. The first simulation shows the results for the year 1999. In the Ex-post-analysis from this year both different Howitt-methods, the cost side specification and the yield side specification of the non-linear gross margin function, get compared. Both methods calculate nearly the same results, the forecast of the production activity levels and the gross margins are nearly the same. For the total research area both methods either over- or underestimate the production activity levels for the same crop. If the forecast results are compared by district the forecasting accuracies were different. A system, that one method is better than the other method, can not be found. For the simulation of the scenarios the cost side specification was used. In the first scenario the year 2008 under the conditions of the agenda 2000 was calculated. The production levels are nearly the same as in the reverence year. The consequences of the mid term review of the European Commission are forecasted in the two other scenarios. The conditions under mid term review have a big impact on agriculture, because of the decoupling of the agricultural subsidies from the products. In both scenarios, the cattle meat production decreases. The same results can be shown with the reduction of silo maize and of grassland. On the other side set aside arises in all districts. Positive for the water resources are the reduction of nitrogen load from organic manure. One of the main conclusions is that the positive quadratic programming is an alternative to the linear models for analysis of farms by district level. Of course the aggregation mistake from the aggregation of different farm types to one big district farm can not be carried out. But the positive aspects of the PQP, which are described in literature, can be permitted. A further research theme, which is not answered in this thesis is the combination of the non-linear gross margin with useful econometric methods.Publication Numerische Modellierung und Simulation der räumlichen und zeitlichen Variabilität von Lachgasemissionen aus Agrarökosystemen(2005) Huber, Stefan; Doluschitz, ReinerThe aim of this dissertation is to characterize the spatial and temporal variability of nitrous oxide emissions from agroecosystems by means of linking mathematical simulation models to Geographical Information-Systems (GIS). Specifically, this study tries to accomplish a methodological goal and a thematic goal. A general software framework for the linkage of agroecosystem-modells and GIS by employing object-oriented and component-based concepts is developed. As an example for the implementation of this framework, the agroecosystem-modell DNDC, the two-dimensional soil water model SWMS2d, and GIS are integrated to the new model Spatial DNDC. This new model is applied to the study of the spatial and temporal variability of nitrous oxide emissions from agroecosystems at different scales. The simulation of the emissions at 281 independent soil profiles from a 40 ha field in Michigan/USA for nine years shows a large temporal and spatial variability ranging from 0.35 to 4.21 kg N2O-N/ha/a. Except for three years the yearly emissions are always lognormal distributed. While comparing simulated and measured daily emissions cannot be regarded as satisfactorily, it can be shown that the median of the daily N2O-emission rates can be employed as a characteristic measure for the given site. The influence of lateral soil water movement on the emission of N2O is studied by employing SpatialDNDC on a dataset from Scheyern/Bavaria, which comprises measurement data for five sites along hill-slope transect for the year 1997. The simulated daily emission rates are very similar for the five sites and are in good agreement with the measurements. The temporal variability of the daily emission rates is largely shaped by the occurrence of nitrogen fertilization-events and following precipitation events. By looking at the yearly emissions a distinct, downslope-directed gradient can be seen with the highest emission of 6.87 kg N2O-N/ha/a at the highest hill position, and the lowest emission of 6.37 kg N2O-N/ha/a at the lowest hill position. This gradient can be explained by the soil water household which is largely influenced by a dry period in spring. Due to lateral water movement plants growing at lower positions have more water available for early-spring growth leading to higher water extraction during the dry period. Therefore the average soil water content, which is a major impact factor for N2O-emissions in SpatialDNDC, lower at the downslope positions as compared to the upslope positions. The modelling of N2O from agroecosystems in the North-China-Plain can merely be regarded as a test case for application of SpatialDNDC to larger regions and whole nations, respectively, since detailed input and validation data are missing. The three simulation studies show distinctively the two main problems of the regional usage of agroecosystem models: On the one hand detailed input data are missing leaving for the modeller only the option to make simplifying assumptions and thereby introducing great uncertainty into simulation results. On the other hand regional calibration and validation data are missing, which are crucial to the realistic depiction of variability within large study regions.Publication Qualitativer Vergleich von Modellen zur Bewertung von Klimaschutzmaßnahmen in Europa unter besonderer Berücksichtigung der Landwirtschaft(2006) Vabitsch, Anna Maria; Zeddies, JürgenAgriculture in Europe is responsible for a considerable fraction of greenhouse gas emissions. Methane, nitrous oxide and carbon dioxide emissions from agricultural sources account for about 10% of the total European greenhouse gas emissions. The contribution that agriculture can and should make to the achievement of the agreed European goals for emission reductions has to be assessed. The aim of this study is to analyse the possibilities and conditions for greenhouse gas mitigation in the agricultural sector in comparison to other economic sectors. It addresses the question of how meaningful and efficient it is to reduce greenhouse gas emissions from farming. A review of the literature showed that various measures for emissions reductions are available for agriculture as well as for the other sectors. In order to assess the efficiency of these mitigation measures, a quantification of abatement costs is necessary. For this purpose, economic-ecological models were chosen which were developed mostly for political advice and analysis. A detailed analysis and assessment of the chosen models was carried out in order to evaluate the model results. The comparative assessment of model results arrives at the conclusion that there is presently no model available that satisfies all the requirements demanded of an environmental indicator for climate policy. For this comparison of models, a selection of representative models was described and analysed in detail. The following models were chosen for the detailed analysis and assessment: POLES, MERGE, EPPA-EU, PRIMES / GENESIS, RAINS / GAINS, CAPRI, AROPA GHG and RAUMIS. They were differentiated between highly aggregated models which represent the global economy with its impacts on the climate system and, in contrast, disaggregated models which focus on a single sector and/or region. Two categories of model structures were observed: general and partial equilibrium models based on the neo-classical economic theory of perfect markets and, on the other hand, optimisation models which were solved by the maximisation of (regionally weighted) profit and benefit. An important feature which distinguishes between the models is the sectoral and material resolution. Aggregated energy models are commonly used, most of which not only reproduce the energy sector, but also the other sectors. However, they only account for energy-related CO2 emissions. These models provide important information on the most relevant emitting sector (energy) and the most important greenhouse gas (CO2), but they neglect the presence of the other Kyoto-gases and the possibilities of an integrated approach for emission reductions. The results of assessments of mitigation potential in the agricultural sector using energy models are incomplete because the relevance of non-CO2 emissions and their possible contribution to overall emission reductions are disregarded. As a second focus models of the agricultural sector were analysed and assessed. These models describe the agricultural production process with a high degree of resolution and determine specific mitigation costs of single measures and options. Additionally, some of these models assess the interactions and effects of simultaneously reducing emissions of different greenhouse gases. However, the problem still exists that results from models of different sectors are not comparable with one another. The main reasons for this are the varying model assumptions and the specific conditions. A method to resolve this dilemma is provided by the models that integrate top-down and bottom-up elements in one model framework. This means that several sectors and countries are simultaneously modelled (top-down) but detailed information on specific gases and mitigation options is integrated as well (bottom-up). Using this procedure, the comparison of different sectors is possible and sector-specific accuracy in the definition of abatement costs, for instance, is also achieved. This procedure is most advanced in the case of integrated assessment models. This approach aims to account for as many aspects as possible of one environmental problem as well as for all its interactions and impacts on other environmental goals. At present, these very complex model systems are most readily applicable to find solutions for the optimal spatial, temporal and material allocation of mitigation measures and investment. The significance of these model results is, of course, also dependent on the available database and on the assumptions made. These models come to the conclusion, among other things, that the integration of agricultural greenhouse gas emissions into a holistic mitigation approach may provide a significant reduction in mitigation costs. Despite the high level of uncertainties regarding the model results, it can be concluded that the agricultural sector should definitely contribute to achieving the agreed emission reductions.Publication Betriebswirtschaftliche Analyse des Einsatzes moderner Agrartechnik in der Körnerfrüchteproduktion in Russland.(2007) Vorontsova, Tatiana; Zeddies, JürgenThe dissertation in hand refers to the optimisation of conventional cultivation methods by the use of resource-saving technologies in cereal production at six agricultural survey enterprises in the Region of Samara/Russia. The aim of the optimisation is to estimate the economic efficiency of the changeover from conventional to resource-saving cultivation methods as well as to evaluate the use of agricultural machinery adapted to the specific technology, and, starting from this basis, to develop practice-oriented and efficiency-increasing solutions. Agriculture is still one of the most important branches of the economy in the Region of Samara on the middle Volga. The climatic conditions are not optimal for a successful grain production, while this branch plays an important role in the region. Despite of the positive development, in grain production in the Region of Samara the production potential has not yet been completely used. During the last years a considerable reduction in the agricultural machinery stock could be noticed, mainly because of obsolescence and wastage of the agricultural machinery as well as the small number of new purchases. The equipment at the disposal of the agricultural enterprises for plant cultivation, during the years 1990 to 2002 ? if compared to the requirements in agricultural technics ? amounted to approximately 46 percent of the tractors needed and approximately 56 percent of the combine harvesters needed. This entailed that the optimal time periods were not matched which, as a consequence, led to the reduction in the yields and an extension of the area not harvested. In order to create favorable conditions for an efficient grain production and for the development of the grain market in the Region of Samara, in 1998 the programme for the "Improvement of the grain production by the application of resource and accordingly watersaving cultivation methods 1998-2002" was starting to be implemented. The changeover from conventional cultivation methods to the use of resource-saving methods including modern and efficient agricultural technics represents a big challenge especially for medium-sized and small farms with a restricted financial potential. Through excluding ploughing from the soil cultivation work process as a most cost-intensive operation, as a result of the optimisation, machine costs can be reduced considerably under the system of preserving soil tillage. On average, these machine costs amount to 18.3 ?/ha with no-till cultivation, and are thus approximately 6 percent lower than with the conventional cultivation methods that were practised in the survey enterprises before. The average machine costs for direct drilling methods amount to approximately 15 ?/ha and can consequently be further reduced by about 18 percent if compared to no-till cultivation methods, and by approximately 22 percent if compared to conventional production methods. However, in the case of applying modern agricultural technics for resource-saving cultivation methods, the resulting fixed costs considerably surmount those of conventional cultivation methods. The modern agricultural machinery shows, however, a substantially higher performance potential. In the long-term, it can be assumed that the modern agricultural machines in this context are the more efficient solution. Moreover, the economic efficiency analysis of the cultivation methods? rearrangement rendered considerable advantages as to the development of labour demand and costs at the questioned agricultural enterprises. The application of resource-saving cultivation methods contributes to a noticeable decrease in labour demand. Under application of optimised cultivation methods, the labour cost is approximately 1.3 ?/ha or 60 percent lower than the total labour costs in the case of conventional cultivation methods. Although the implementation of resource-saving cultivation methods basically does not require an intensified application of fertilisers and pesticides, their aplication volume is being raised and adapted to the necessary level within the frame of the optimisation process. Under favourable weather conditions thus an increase of the yield per hectare as well as of the quality, and in the medium-term, a positive influence on the cereal production can be expected. As result of the conducted optimisation of cultivation methods and of the implementation of the recommended measures at the survey agricultural enterprises in the Region of Samara, a change in the obtained gross margin can be detained. The average gross margin decreases under no-till cultivation by approximately 24 percent and amounts to 58 ?/ha. The calculated gross margin for the direct drilling methods amounts to 61 ?/ha and is still below the amount effected under conventional cultivation methods. The calculated equilibrium points at the fact that the implementation of the optimised cultivation methods requires an increase of the hectare yield in the survey farms by 2.5 dt/ha on average. In order to reach a positive economic effect or at least the same economic efficiency as with use of conventional cultivation methods, the hectare yield should be increased to approximately 23 dt/ha or, by 12 percent. In spite of the findings resulting from the optimisation calculations that the gross margins are reduced with direct drilling as well as with no-till cultivation methods, the results in Samara Region, however, indicate a continuous increase of the economic efficiency under the condition of a long-term application of resource-saving cultivation methods in cereal production. The rearrangement of the conventional cultivation methods towards the optimised resource-saving technologies is under these conditions for the survey agricultural enterprises advantageous in a long-term view.Publication The Competitiveness of the Sugar Industry in Thailand(2007) Arjchariyaartong, Wuttipong; Zeddies, JürgenThailand is now firmly established as one of the world?s leading sugar exporting countries. During 1995/96 to 2005/06, sugar exports ranged between 2.3 and 5.1 million tons and averaged 3.80 million tons per year. For this reason, sugar cane production is one of the major economic sectors in Thailand. There are several activities involved in the production process such as sugarcane growing, sugar milling, credit banking, exportation, etc. The sugar production activities provide significant full time and temporary employment in sugar factories, sugar transformation, transportation and exports. Therefore, the study of sugar cane and sugar industry?s competitiveness is important, especially with the increasing liberalisation of the world market. Based on the above considerations, this thesis has key objectives as follows: 1. To study the structure of sugarcane and sugar production in Thailand. 2. To analyse costs and returns of sugarcane and sugar production in Thailand. 3. To examine the competitiveness of the sugar industry and identify indicators of competitiveness. 4. To describe strategies of sugarcane growers and sugar factories for improving competitiveness. The methodology applied for the farm sampling is based on the concept of typical farm approach. Farm types are determined by sugarcane experts taking into consideration: location of farm, farm size, sugarcane area and share of rain-fed and irrigated area. The first category of farms was chosen to represent the size that is close to the statistical average. The other types defined represent larger farms to allow the exploration of potentials for economies of size in the region. Management levels on the typical farms are above average. The sugar factories were categorized by region, industry group and crushing capacity. Firstly, the structure of sugar cane production in Thailand can be described as follows. Sugar cane is grown all over the country. The total cane area amounted to 6.34 million rai in 2004/05. The most important regions of sugar cane production are the Northeastern, the Central and the Northern region. The total cane production amounted to 47.82 million tons in 2004/05 with an average yield of 7.54 tons/rai. Secondly, the structure of the sugar industry in Thailand can be described as follows. Within the total number of 46 sugar factories, there are 4 large factories with a crushing capacity of more than 24,000 tons of cane crushed per day, 16 medium size factories (12,000-24,000 tons/day), and 26 small size factories (< 12,000 tons/day). Thirdly, the sugar market in Thailand can be described as follows. The total sugar production amounted to 7 million tons in 2003/04. With a share of domestic consumption of 27.8%, only around 2 million tons of sugar is used for domestic consumption. The rest of around 5 million tons of sugar is exported to the world market, mostly to Asia. The wholesale prices for the domestic market are annually fixed by the government to around 12 Baht/kg in the average. Fourthly, the results of sugarcane farms can be concluded as follows. The analysis of sugarcane costs of production has shown that the total production costs of sugarcane farms for the first ratoon are highest and then decrease in the second and third ratoon. The farms in the Central region have higher average production costs (4,245 Baht/rai) than the cane growers in the Northeast (4,130 Baht/rai) and in the North (3,725 Baht/rai). Low labor costs, especially harvesting costs of around 1,142 Baht per rai, are the predominant reason for the lower cost structure of the farms in the Northeastern region. Fifthly, the results of the sugar factory analysis can be concluded as follows. The five investigated factories are one large factory with a crushing capacity of more than 23,000 tons of cane per day, and four small factories with a cane crushing capacity of less than 12,000 tons/day. Although most of the cane suppliers are small size farmers, the majority of cane comes from medium and large farms. The sugar sales are depending on the type of sugar and the market channel and range from 14 Baht/kg to 18 Baht/kg. The average distance of sugarcane transport is around 53.33 km for sugarcane which is purchased from sugarcane farmers. The closer the sugarcane fields to the factory are the higher is the competitiveness of the sugar factory. The productivity analysis of the sugar industry shows that factory C possesses an advantage with respect to the quantities of total sugar production per rai in production year 2002/03 and 2003/04. The result of ranking the sugar factories according to their competitiveness shows that factory C has an advantage in the total quantity of sugar production per rai. Factory E had the highest advantage in the extraction rate of sugar per ton of sugar cane and gained the highest profit of sugar production. However, factory B has the highest ability to produce sugar with the lowest costs per kg and factory D was the leader in reducing costs of sugar production in Baht per rai. In the summary, the score over all indicators of competitiveness shows that factory E has the highest score. Therefore, factory E has been ranked to be the most competitive factory, followed by factory B, factory D, factory A, and factory C respectively. Finally, this study provides suggestions and policy recommendations for sugarcane farms and sugar factories in four areas. First, sugarcane productivity per rai is still low in Thailand, therefore research and development is necessary in the field of optimization of the production process and breeding of new sugarcane varieties. Second, enough water and access to irrigation system is very important for sugarcane planting, so the government should help to provide these facilities for the farmers. Third, the sugar industry should differentiate their sugar products in order to increase the value added of sugar production. This will help sugar factories in case of encountering the situation of low prices of sugar. Fourth, due to increasing energy costs, sugar factories should get support in acquiring alternative energies and reducing other costs of production by research and development.Publication Economic evaluation of nitrogen application in the North China Plain(2008) Barning, Roland; Zeddies, JürgenToday, China had solved its long-standing problem of inadequate grain production, but there are two new targets for rural China. Firstly, one goal is rural development towards an improved income generation of rural households in order to slow down the increasing income disparity in China, especially between rural and urban residents. Secondly, decades of inefficient utilisation of resources and high consumption of materials led to overexploitation of water and land resources. Over-fertilisation and low nitrogen use efficiency are representative for the production system in the North China Plain, which is characterised by small-scale farm households who traditionally cultivate winter wheat and summer maize. This thesis is embedded in the Sino-German Research Training Group "Modeling Material Flows and Production Systems for Sustainable Resource Use in Intensified Crop Production in the North China Plain", a cooperation of the University of Hohenheim in Stuttgart and the Chinese Agricultural University in Beijing. The overall hypothesis of this project is that substantial changes in farming systems and management practices can reduce environmental pollution and at the same time stabilise or increase income of farmers. As a subproject, this thesis focuses on the identification and evaluation of applicable instruments for this goal. The final target of this thesis is the simulation of scenarios in order to estimate the impact of identified instruments on the nitrogen balance as well as on the net income of farm households. The literature review indicates that nitrogen application in the cultivation of wheat and maize in the North China Plain shows a broad variation. A considerable high share of farm households applies nitrogen input levels far beyond the crop demand. This situation raises the question, what do over-fertilising farm households have in common or in another way, which factors lead to nitrogen overuse. This question is the basis of the discussion on applicable instruments to reduce the described nitrogen overuse and finally the intended simulation approach. The analysis of impact factors on the nitrogen application level requires a broad analysis of the cultivation system, the farm household characteristics, and the income sources of the farm households. The descriptive results of the farm survey on 340 farm households in the North China Plain conducted in 2005 are presented in chapter 5. The farming system at the survey sites is characterised by farm households, who cultivate the wheat and maize rotation system. In most cases, it is extended by cash crops such as cotton or peanuts. The farm size is on average 0.5 ha of allocated farmland per farm household. About two thirds of the farm households have some kind of additional off-farm income source, which usually exceeds the income share from farming. Farm households without off-farm income sources generate only half of the average farm household income. The average farm household income reaches 10 150 ¥ (1 015 ?) per year, but there is a broad variation within the survey sites as well as between the surveyed townships. As mentioned already, over-fertilisation is prevalent for farming in the North China Plain. On average 360 kg of nitrogen per ha are applied in wheat and 220 kg in maize, while CHEN (2003) recommends 180 kg per ha for wheat and maize. Further, fertilizer costs are the major share of variable costs at all cultivated crops. The major nitrogen fertilizers are urea and ammonium carbonate. Nearly 80 per cent of the applied nitrogen originates from these fertilizers. Manure is only applied in wheat and it plays only a minor role as nitrogen source. About one third of the farm households cultivates wheat exclusively for own consumption and these farm households apply more nitrogen in wheat cultivation than the remaining farm households. The average yield of 5.7 t per ha in wheat and of 6.4 tons in maize enables gross margins of about 4 000 ¥ (400 ?) per ha, while in cotton and cultivation of peanuts the average gross margin is twice this amount. In chapter 6 the efficiency of the agricultural system is analysed. This analysis includes an impact analysis on nitrogen input and yield as well as an economic and ecologic optimum analysis of the nitrogen input. Nitrogen application rates show a broad variation at all cultivated crops. The impact analysis on nitrogen input does not show any clear and unique influence from the income structure of the farm household. Hence, additional cash income and less available family work force for farm work have no impact on the nitrogen application level. The analysis of the fertilizer costs instead of the amount of applied nitrogen confirms this statement. The nitrogen input analysis provides the nitrogen price as major impact factor. Higher nitrogen input levels are connected with lower nitrogen prices. Differences in nitrogen price result from the composition of the applied fertilizer, which differs in the ratio between fertilizer price and nitrogen content. The yield of wheat and maize indicates a high variation within the survey sites, but especially between the surveyed townships. A multifactorial regression analysis identified the location as the only significant influencing factor on yield. From the agronomic point of view, nitrogen is a major yield factor, but the survey data do not indicate a clear impact of nitrogen input on yield. The estimated relationship between nitrogen input and wheat yield provides a constant-shaped yield function. This result allows the assumption that due to the long term high nitrogen inputs the crop demand for nitrogen is fulfilled in the short term and additional nitrogen input is without impact on the yield. The quadratic regression models of nitrogen input and yield in wheat and maize fail to provide applicable economic optima of nitrogen input. For this reason, the concept of KRAYL (1993) is considered to estimate an applicable production function for wheat and maize. This concept is based on a location independent production function, which can be transferred into a location specific production function by the consideration of a location specific optimum nitrogen input and the corresponding yield. In this case the recommendations of ZHEN et al. (2005) are considered, which recommend for wheat a nitrogen input of 220 kg per ha in order to harvest 5.3 t per ha. The economic optimum nitrogen input levels are higher than the nitrogen recommendations of ZHEN et al. (2005), but still lower than the average nitrogen application rates. Hence, the present nitrogen price does not support the implementation of the recommended nitrogen application rates. The estimation of the economic optimum nitrogen input considers a production function based on the concept of KRAYL (1993) which is enlarged by factor and product prices. These are the crop prices and the costs of the other variable inputs, which are the variable costs excluding fertilizer costs. In this way, the gross margin can be described as a function of nitrogen input including the uniform factor crop price and the constant "other fertilizer costs". The calculated maximum gross margin in wheat of 4 057 ¥ per ha is achieved at a nitrogen input of 272 kg per ha. This level of nitrogen input is lower than the present average nitrogen input, but higher than the recommendations presented by ZHEN et al. (2005). Similar to the gross margin, the nitrogen balance is described as a function of nitrogen input, which considers the nitrogen input from fertilizer and straw left on the field from the previous cultivation as nitrogen inflow and the nitrogen content of the harvested crops as nitrogen outflow. Natural inflows and outflows are not taken into account. A nitrogen input of 205 kg per ha would result in the maximum accepted nitrogen surplus of 50 kg per ha and a gross margin of 3 365 ¥ per ha. Chapter 7 focuses on the estimation of the nitrogen balance and the analysis of relevant impact factors. The estimated nitrogen balances show at all crops, but especially in wheat cultivation a high level of nitrogen surplus, which is on average 200 kg of nitrogen per ha. The corresponding figures for maize, peanuts, and cotton are less than 100 kg of nitrogen per ha. Similar to nitrogen input, the nitrogen balance is indicated by a broad variation. This variation allows a classification of farm households into three nitrogen balance types: "equalized nitrogen balance", "slight nitrogen surplus", and "heavy nitrogen surplus". The farming system of "heavy nitrogen surplus" farm households can be characterized by low yields, high nitrogen input, and low calculated gross margin. These farm households have a share of 32 per cent of all farm households and cultivate about one third of the wheat of all surveyed farms, but their cumulated nitrogen input amounts to 50 per cent. Furthermore, this group of farm households accounts for 67 per cent of the cumulated nitrogen surplus. This situation leads to the question, which factors lead to that kind of nitrogen overuse. A binary logistic regression model is used to analyse the impact of pre-selected factors on the probability of a group membership interval, in this case to the "equalized nitrogen balance" as well as the "heavy nitrogen surplus" group. The covariates "family size", "education", "farmland", and "off-farm activities" do not show any significant influence. Similar to the nitrogen input analysis, a low nitrogen price and the application of manure increases the probability of a farm households of membership of the "heavy nitrogen surplus" group. Also, a low village average wheat yield and a high village average nitrogen input in wheat increases the probability. In order to identify parallel impacts of farm household characteristics on the nitrogen balance the group of farm households of "heavy nitrogen surplus" and "equalized nitrogen balance" are clustered. The farm households of the major cluster of the "heavy nitrogen surplus" group are characterized by less farmland and low farm households income without off-farm activities. Farm households of these characteristics are found at a minor cluster of the "equalized nitrogen balance" group, as well. A low income does not automatically lead to nitrogen application rates beyond the crop demand. Indeed, the combination of low income and high nitrogen input shows a higher probability than the combination of high income and high nitrogen input. Without doubt, the assumption that a lower income leads to a lower nitrogen input must be rejected. The nitrogen price might be a clear indicator for classification of farm households, but this criterion requires the analysis of the cultivation system of the considered farm household. For this reason, easy observable dichotomous variables are pre-selected and analysed whether a certain pattern can be used as criterion for identification as a part of a target group specific instrument. This approach does not provide applicable results. Chapter 8 deals with the simulation of scenarios of the nitrogen surplus reduction and the estimated impact on the net income of farm households. In the first step, the instrument independent potential nitrogen surplus reduction is estimated. The cumulated nitrogen surplus of wheat cultivation of all surveyed farm households can be reduced by more than 60 per cent, if all farm household would follow the nitrogen input recommendations and harvest the target yield of ZHEN et al. (2005). This scenario shows no changes in net income. However, the approach that all farmers would modify their present nitrogen application level to the recommended application rates might be too ambitious. Hence, it might be more realistic to consider a theoretical shift of half of the farm households belonging to the "heavy nitrogen surplus" group to the "slight nitrogen surplus" group. The nitrogen surplus reduction in wheat would be 18 per cent. The affected group of farm households represents 17 per cent of the wheat cultivation area, but accounts initially for 32 per cent of the total nitrogen surplus in wheat. This hypothetical shift considers the modification of the share of farm households belonging to a certain nitrogen balance type. The average nitrogen surplus and gross margin in combination with the share of farm households of nitrogen balance type is taken to estimate the overall nitrogen surplus and net income from farming of the considered nitrogen balance type. A change in the share of farm households modifies the overall nitrogen surplus and net income from farming of each nitrogen balance type and these modified values are considered as the impact of the evaluated instrument, which originate that change of share. The individual gross margin multiplied by the individual cultivation area of all farm households is summed up and it is considered as net income from farming. In the following step, the impact of an instrument on the nitrogen balance and the net income is simulated. The variable nitrogen price shows a highly significant influence towards the classification of nitrogen balance type. For this reason, a modification of the nitrogen price is selected as considered instrument. A higher nitrogen price reduces the probability of "heavy nitrogen surplus" and this difference in probability can be regarded as the share of farm households, which convert form "heavy nitrogen surplus" to "slight nitrogen surplus". In addition, a theoretical shift of "slight nitrogen surplus" farm households into "equalised nitrogen balance" farm households is considered. As instruments, a percental increase of the nitrogen price by 10 per cent is simulated. An increased nitrogen price by 10 per cent results in a reduction of the total nitrogen surplus of 4.9 per cent. The estimation of the impact on the net income from farming considers the described theoretical shift of farm households to another nitrogen balance type and a multiple regression model of the gross margin. The latter model considers all farm households and indicates a negative impact of the nitrogen price on the gross margin. A combination of both models results in a marginal reduction of net income from farming by 0.6 per cent, in case of a 10 per cent nitrogen price increase. In addition, a target simulation focuses on a more noticeable nitrogen surplus reduction. The average nitrogen price increase by 159 per cent to obtain a nitrogen surplus reduction of 50 per cent, but the net income from farming shows a reduction by 15.3 per cent. Summarized, the considered instrument "nitrogen price modification" fulfils the demand partly. It allows a nitrogen surplus reduction without a strong impact on the net income, but there are two major disadvantages. Firstly, huge nitrogen price modifications are required to gain a noticeable impact on nitrogen surplus reduction. Secondly, a nitrogen price modification affects all farmers, but there is a broad variation of the nitrogen balance and a high share of farm households actually has an equalized nitrogen balance. The discussion about the reasons for nitrogen overuse in the wheat and maize farming system in the North China Plain leads to the following results. This thesis cannot provide a comprehensive answer on the question, what the core reasons for the described surplus at the nitrogen balance are. The described high variation in nitrogen input and the reported low rate of farm households, which follow the recommended nitrogen application rates, leads to the assumption that an insufficient knowledge transfer system is the key reason for the inadequate use of the traditional cultivation system in terms of fertilizer application in the North China Plain. Lack of knowledge might be an explanation that low income farm households without off-farm activities do not have less fertilizer costs, but even have a higher probability to apply above average nitrogen rates than farm households, which have additional income from off-farm activities. The discussion about applicable instruments focuses on nitrogen tax, implementation of new agricultural technologies, and improvements in education and agricultural skills. The modification of the nitrogen price by a nitrogen tax is considered as an economically applicable instrument, but there are the described disadvantages. Furthermore, an economic instrument might not be suitable, if a noticeable share of the target group seems not to consider their farm level economic optimum as criterion in their determination of the applied nitrogen. In addition, a low nitrogen price is a suitable indicator for nitrogen overuse, but not its explanation. The nitrogen price represents the composition of the used fertilizer. An unfavourable composition can be regarded as an insufficient use of the cultivation system, which results in the described nitrogen overuse. Hence, an improvement in application of the cultivation technology might be more successful than an economic instrument. The discussion about new technologies focuses on their implementation. Only a minority of farm households follows the presently recommended nitrogen application rates and at a noticeable share of farm households the traditional cultivation system is not free of cultivation mistakes, especially in terms of nitrogen application. This raises the question, how successful a new agricultural technology can be implemented. The correct application present of the cultivation system and a proper working knowledge transfer system are the preconditions for the implementation of new technologies. For this reason, improvement in education and agricultural skills are the base instruments as well as the basis for all advanced instruments, because a sustainable cultivation system requires a sustainable implementation of its correct use.Publication Structural change requirements in the Bulgarian dairy sector aiming at higher competitiveness within the EU(2008) Vassilev, Zlatan; Doluschitz, ReinerDuring the burdensome years of transition the agriculture in Bulgaria plays the role of a social buffer and a sector providing some, although insufficient, income and employment. Although employment in agriculture is a source of income, self consumption of its products can save income that could be spend on something else. The differences between market and self-sufficiency oriented farmers diminish due to income instability, that consequently contribute to agricultural decommercialization. A major characteristic of small-scale subsistent farming is the diversification of production activities that usually lead to diseconomy of scale effects. At the same time small-scale subsistent farms use labour intensive systems of production as a substitution for the scarcity of capital and machinery. Subsistence farming uses resources which could be used elsewhere in market-oriented farming and other sectors and its existence may cause a loss of overall production efficiency. Notwithstanding this loss of efficiency at the aggregate level, subsistence farmers may be efficient with regard to their own utility functions. Consequently, from a conventional economics point of view, small-scale farmers are unlikely to react to government policies in a normal, "rational" way. However, when they dominate the production of some products, predictions based on ?normal? economic models may be unreliable. The scope of the study is to cover the agriculture holdings with dairy cows according to the national statistic and moreover to argue that not all of them can be defined as dairy farms. The general hypothesis of this thesis states that the current typical dairy farm can double its size and increase significantly its income while reducing the risk for the household. On the contrary if it is growing more than a double that would have the opposite effect due to overestimated management capacity and unacceptable size of liabilities. The method used in this thesis is based on the concept of a typical dairy farm through bottomup approach. A typical dairy farm represents a significant number of dairy farms in a region in terms of size, forage and crops grown, livestock systems, labour organization and production technology used, and show an average management / performance ratio. The typical farm is ?built? and ?validated? based on panels (farmers, advisors? knowledge and local experts) and farm accounting statistics. The simulations in this thesis proved that with the currently existing support programs a successful farm restructuring is viable in a short period of time if the farmer possesses the necessary skills, knowledge and information to adopt a strategy to successfully face the changing market conditions. While the suggested structural changes could be successfully implemented in order to provide a significant improvement of the management, the time span available for them is very ?narrow? with respect to the financial support provided by the programs available. The general assumption of the government policy was that the ?Producer Union? (PU) should play a leading role in the process of structural reforms in agriculture. Unfortunately that assumption didn?t justify itself, consequently the provision of high qualified management services (as a major benefit from the membership in the PU) to the farmers is not utilised by them.Publication Simulation of the sustainability of farming systems in Northern Thailand(2008) Potchanasin, Chakrit; Zeddies, JürgenIntroduction Due to an increase in environmental problems and resource degradation, economic development should be pursued with consideration of environmental functions and the supply and quality of natural resources. Monitoring and assessment of whether the development approaches a sustainable path are required to provide information for policy development. This becomes increasingly important ? especially for marginal areas where the environment and natural resources are sensitive. The study area is located in the mountainous area of Northern Thailand with abundant natural resources and a healthy ecological environment. However, population growth, land limitation, and external factors ? such as market forces ? are inducing change and pressure on resource utilization. The resources are intensively used and farming systems are changing to more commercial practices. Therefore, the region?s long term sustainability needs investigation. Objectives This study aims at assessing the sustainability of the farming systems in the study area under the sustainability concept, farming systems approach and Multi-Agent Systems (MAS) approach. The first objective of this study is to describe the characteristics of the farming systems in the study area. The second objective is to develop and use a MAS model to evaluate sustainability of the study area. The last objective is to use the model to present sustainability of farming systems under different scenarios based on changes of significant factors and policy intervention. In addition, the ability of the systems to cope with and recover themselves from these changes is examined. Methodology The sustainability of the farming systems in the study area was assessed through defined indicators representing three conditions: the economic, social and environmental condition. The indicators were defined based on the framework of indicator determination to serve the objectives and methodology of this study. The selected indicators for this study are: household income, net farm income, household capital, household saving, food security, top-soil erosion and fallow period. For these indicators the following sustainability classes were defined: Sustained (S), Conditional sustained (C), and Non-sustained (N) class. Evaluation of sustainability was carried out at two levels: the household and the village level. At the household level the sustainability situation was evaluated based on the individual farm household performance corresponding to each indicator. The sustainability at village level was assessed through the Sustainability index (SI) when single indicators are considered and the Performance index (PI) in which a group of indicators is regarded. The dynamics of the sustainability situation at household and village level were extrapolated over 15 years (2003 ? 2017) in order to examine the sustainability of the study area?s farming systems. The MAS model was developed and named CatchScapeFS. The model structure relies on descriptions of the farming systems in the study area. The MAS approach was applied in order to capture the complexity and extrapolate the long-term sustainability situation in the study area. The model composes of two components: a biophysical and a socioeconomic component. The biophysical component is based on the CatchScape3 model. It consists of biophysical models: a hydrological model, a crop model, a water balance model and a soil erosion model, which are embedded in the landscape model of the study area (represented in spatial grid cells as plots of one rai or 0.16 ha). The socioeconomic component is composed of farm household agents and other social elements. The farm household samples were classified based on the similarity of characteristics and behaviour into the market, subsistence, and partnership oriented group. The Monte Carlo technique was applied to generate farm agents out of the existing farm household samples. The CatchScapeFS model was designed according to the object-oriented modelling approach. The CORMAS platform was selected as a capable tool to facilitate modelling and simulation. During a simulation time step covering 10 days, activities in six principal phases including activities in eight phases of farm agent household activities are executed. The model was validated and tested for its stability. Validation was conducted by social validation and statistic data comparison validation. The results of the model validation and stability test showed the reliability of using the model to serve the study objectives. Main results Sustainability of study area at the household level The results show unsustainability over time in the study area. The number of households in the Sustained class (S) decreases whereas the number in the Non-sustained (N) and Conditional sustained class (C) tend to increase. For the economic condition, unsustained aspects occurred because of rising private household expenditure and decreasing capital products on the farm. For the social condition, the results show an increase of the households? rice deficit and rice acquisition in the long run which enhances the area?s unsustainability. For the environmental condition, erosion and shortening fallow aspects induce the area?s unsustainability. The area?s erosion is severe and increases over time. For the fallow aspect, the average fallow period is shortening because of intensive land use in order to produce for consumption ? which potentially induces land degradation in the long run. Sustainability of the study area at village level Similar to the results at household level, the findings show that farming systems in the study area are not sustainable. Unsustainability was observed by a declining Performance index (PI) and declining Sustainability indexes (SIs) of all indicators in the long term. By considering PI values with the trends, the area?s sustainability in economic condition is better than the social and especially environmental condition. This can be explained by relative high SI values for the economic indicators compared to the SIs of the social and environmental indicators. By considering all SIs and their dynamic trend, sustainability issues can be ranked to determine the sustainability issues which need to be improved. Food security is the most unsustained issue followed by the issues of household saving, household capital, top-soil erosion, household income, fallow period, and net farm income respectively. Scenario analysis The scenarios were the implementation of a policy to improve sustainability and occurrence of unexpected events through changes of biophysical and economic factors. The scenario of the sustainability improving policy is defined as introduction of a high yield variety of upland rice and maize including introduction of mango to the households who currently only produce annual crops. Unexpected events due to the change of biophysical factors were simulated with a drought and rain increasing scenario. A decreasing crop price scenario represented an unexpected event due to the change of an economic factor. Implementation of proposed sustainability improvement policy The results show that the sustainability in the study area is obviously improved; represented by an increase of the PI value with a positive trend over time. In addition, the SIs of many indicators increase in this scenario, except the SI of household saving, which was rather constant. The PI of economic indicators improves with a higher number of households in the sustainable class when considering the household income, net farm income and household capital indicators. For the social condition, PI and SI values of food security increase because of a reduced rice deficit. For the environmental condition, the PI value of the environmental indicators increases because of a reduction of soil erosion and a longer fallow periods. It can be concluded that this scenario provides a policy option which potentially leads to an improvement of the sustainability situation in the study area. Drought scenario The results show that the study area was still unsustainable similar to the baseline scenario. However, the results show a slightly better PI during drought with a higher value and a slower decrease over time. These are the effects of the trade-offs between the indicators. The top-soil erosion indicator (influenced by decreasing rain) becomes better. This positive effect compensates for the negative effects regarding household savings, food security and fallow period indicators ? which all declined. In addition, the simulation results presented the adaptation and reaction of farm agents to drought. Drought is perceived and causes a delay in planting to avoid damage. This induced a variation of the planted area. However, the variation becomes lower because of adaptation as the farm households learn from their experiences. During drought, an increase in the rice and maize deficiency occurred. The average amount of borrowed rice increased over time and the rice acquisition of the farm agents is performed by borrowing from the village rice bank and neighbours In addition, the farm agents acquire maize by collecting wild vegetables to feed their animals. Furthermore, the results indicate the ability of the farm households to cope with and to recover to some extent from a drought. Rain increasing scenario In this scenario, the study area was still unsustainable, similar to the baseline. However, for this scenario, the top-soil erosion is worse because of the increasing rainfall. The PI of economic indicators slightly increased in the first year with increasing rain because of the rising income from livestock production. However, this was caused by random effects influencing the model?s initial stage. For the social condition, there are only small random changes compared to the baseline scenario. For the environmental condition, the PI and SIs of environmental indicators become worse due to an increase of top-soil erosion. Price decreasing scenario The results show that the area?s sustainability is worse compared to the baseline. A reduction of the crop price directly affects household income and cash ? which consequently generates a cash deficit problem. However, due to the area characteristics and household behaviour, there is no effect on resource use because prices do not influence the farm agents? decision making. The PI of this scenario declines faster than in the baseline. This was affected by the decrease of the SIs of the economic indicators which decreased during the periods of the price fall. The households are confronted with a decline in cash which results in a deficiency of cash. Cash acquisition of the households is performed by selling livestock and borrowing from the village fund and neighbours. For the social and environmental condition, there are only small changes due to random effects. Policy recommendations Based on the study results, policies to improve sustainability of the study area farming systems are recommended. Firstly, to improve the area?s sustainability, the introduction of high yield variety of upland rice and maize with conservation practices as well as the introduction of mango to the farm households who currently produce only annual crops is recommended. Secondly, diverting research efforts to develop cash crop alternatives is required in order to improve household cash income. Thirdly, the promotion and support for raising livestock and off-farm activities, such as weaving and the development of tourism, should be performed in order to increase household cash income. Fourthly, awareness raising measures for stakeholders concerning environmental and resource protection have to be executed and achieved. For this, the CatchScapeFS model can be used as a tool to promote a common view between stakeholders. Fifthly, the introduction of birth control in this area is also necessary. Simultaneously, an understanding of households? regarding the effects of population growth should be created in order to obtain the villagers? cooperation without cultural conflicts. Recommendations for further research Guidelines for further studies and applications are recommended. Firstly, development of the model to be more realistic could be undertaken by representing more details of the systems, for example, introducing a nutrient soil dynamic model. However, this should be based on the considered research question (s) and should consider both the marginal benefits and marginal costs of development. Secondly, application of the CatchScapeFS model to other study areas would need to consider the compatibility of the model components and structure of the characteristics in the new study area. In addition, if applied to new areas the indicators to represent sustainability of the study area should be revised. Thirdly, applications following this study framework can be extended to different sustainability approaches ? such as sustainable rural livelihood or sustainable land management. However, the compatibility and relationship of the indicators with the study framework should be considered. Fourthly, a framework through application of object-oriented modelling is recommended as an alternative for further studies to investigate the consequences of policy interventions. However, resource requirements for any research application should be taken into account. Fifthly, the CatchScapeFS model can be used as a tool to test and monitor the effects of potential policies which can be implemented into Bor Krai village. Also, the model can be used as a tool to promote a common view of the overall village systems as well as to support collective decision making managed by stakeholders of the systems. Recommendations for newcomers to MAS application research Suggestions from the present study for newcomers have been proposed. The first recommendation to deal with the MAS application research is that newcomers have to learn the computer programs and programming. Learning programming with advice of programming experts at the beginning period and attention of newcomers to apply the code in different circumstances are highly recommended. Secondly, development of an integrated model in multidisciplinary research requires learning the academic knowledge from other disciplines. Therefore, determining the study objectives within the possible extent, introducing assumptions to simplify the additional disciplines, and consulting specialists to learn the required knowledge within a short time frame are suggested. Lastly, the development of integrated model requires a huge amount of data. Therefore, in the case which required data cannot be obtained, introducing assumptions based on theory and literature is recommended.Publication Economic analysis and policy implications of wastewater use in agriculture in the central region of Ethiopia(2008) Weldesilassie, Alebel Bayrau; Dabbert, StephanThe general objective of this study was to analyze the impact of wastewater use in agriculture. It mainly focused on three aspects of wastewater use for irrigation and their policy implications: impact on crop production and productivity; its impact on the health of farmers; and the value attached to its safe use for irrigation. The main objectives of the study were, therefore, 1) to define the farming system of wastewater farmers and to analyze the impact of wastewater on crop productivity; 2) to analyze the prevalence of the actual health risks to farmers and estimate the health costs associated with the use of wastewater in irrigation; and 3) to estimate the farmer?s willingness to pay for improved or safe use of wastewater for crop production. This study used mainly primary data collected from a household survey conducted on 415 wastewater and freshwater farm households operating irrigated agricultural activities within and around Addis Ababa, a central region of Ethiopia. A Cobb Douglas production function is specified to analyze the impact of wastewater on crop productivity. The production function was estimated using a Censored Least Absolute Deviation (CLAD) econometric model. To analyze the health impact of wastewater, the probability of illness was estimated based on the theory of the utility maximizing behavior of households subject to the conventional farm household production model modified by adding a health production function. The economic value of safe use of wastewater is estimated from data obtained from a contingent valuation survey administered by in-person interviews. A dichotomous choice model is used to elicit the farmers? willingness to pay. Bivariate probit and interval regression models are used to analyze the factors determining the farmers? willingness to pay for safe use of wastewater for crop production. The study shows that the livelihoods of wastewater farm households depend on the wastewater farm. Income from a wastewater farm accounts for 62% of total annual household income, ranging from 27% to 97%. About 61% of the vegetable market of Addis Ababa, the capital city of Ethiopia with more than five million people, is produced from the wastewater farms. Leafy vegetables, which are eaten raw, are mainly produced in less polluted wastewater farms and root vegetables are produced in more polluted wastewater farms. The study revealed that wastewater farm households use significantly less doses of chemical fertilizer compared to the freshwater irrigators. However, they spend three times more on seed and five times more on farm labor. Net farm return per hectare of plots irrigated with wastewater is significantly higher than for plots irrigated with freshwater. The results also indicate that the predicted median output value per hectare is significantly higher in wastewater irrigated plots compared to plots irrigated with freshwater. The CLAD estimation result shows that higher productivity of wastewater plots is explained by investments in inputs (organic fertilizer, improved seed and agricultural extension services), ownership of plots and levels of pollution of the irrigation water. The overall effect of wastewater on crop productivity is negative and insignificant (compared to freshwater). Plots irrigated with less polluted wastewater are more productive than plots irrigated with more polluted wastewater. The implication of the result is that even if wastewater is a reliable source of irrigation water and contains essential plant nutrients such as NPK, the nutrient content exceeds the recommended level of the plant requirement (e.g. nitrogen) or it contains toxic elements (e.g. nickel, zinc) above the recommended limit, and thereby reduce yield. Due to unsafe wastewater irrigation systems, wastewater use in irrigation actually poses health risks to farmers. Apart from working on wastewater farms, different risk factors prevail that can cause wastewater-related diseases in the studied areas. This study shows that major risk factors causing illness are household demographic characteristics, hygienic behavior of farm families and poor access to sanitation services. Lack of awareness on health risk of wastewater as well as working without protective clothing on the farm are also important risk factors in the study area. The distribution of these risk factors varies between the wastewater and freshwater irrigation areas. The most common incidence of illness reported by farm households are intestinal infection due to hookworm and Ascaris, diarrhea and skin diseases, which also varies between the two groups of farmers as well as within the different areas of wastewater. The findings of this study show that the prevalence of illness is not only significantly higher in farmers working on wastewater farms compared to freshwater irrigators, but is also significantly higher in wastewater areas where the pollution level is higher. The probability of being sick with an intestinal illness is 15% higher for wastewater farmers than for freshwater farmers. Use of protective clothing during farm work and awareness of health risks in working on wastewater farms significantly reduce illness prevalence. In addition, hygienic behavior of farm families including eating safe raw vegetables, compound sweeping, and washing hands before a meal are important determinants of illness prevalence in wastewater irrigation areas. Therefore, use and provision of protective clothing at affordable prices, creating awareness for safe use of wastewater, and reducing the pollution level of irrigation water can significantly decrease the health risk of wastewater use in irrigation. While each of these policy interventions has a significant effect in reducing health risks, combining these measures will result in more significant reduction of health risks to farmers, and thereby maximize the benefit from the wastewater resource as a source of livelihood and vegetable supply to the residents of nearby cities. Farmers are willing to contribute money to improve the existing unsafe irrigation system. Two options were suggested by farmers to improve the existing situation: enforcing laws against polluters who discharge their wastewater without any kind of treatment, and awareness creation of safe use of wastewater for irrigation. Farmers are willing to pay for the improvement programs and there is a welfare gain to the society from safe use of wastewater for crop production. The benefit from irrigated-farming, membership to water users? association, yield value, off-farm income and working on a wastewater farm all significantly determine the farmers? probability of accepting offered bids for the improvement program. In addition to these variables, multi-purpose uses of irrigation water as well as education level determines the farmers? willingness to pay. Irrigation method has no significant effect on the farmers? willingness to pay, implying that introducing water saving and improved irrigation techniques has an important role in improving the situation without affecting the farmers? willingness to pay. Overall, this study shows that wastewater is a means of livelihood for many poor households, but the existing use of wastewater for crop production actually causes health risks both to farmers and consumers. Farmers are willing to contribute to programs designed to improve the existing situation so that it is possible to maximize the livelihood benefit at minimum health risks. However, the results do not necessarily imply that the cost of improving the situation has to be borne by the farmers only. Although the study focuses on the central region of Ethiopia, most conclusions can have a wider application in other parts of the country and in many sub-Saharan African countries where wastewater is used for irrigation.Publication An economic analysis of the implementation options of soil conservation policies(2008) Schuler, Johannes; Dabbert, StephanThe objective of this study is to analyze the economic and agricultural aspects of the implementation of soil conservation programmes and to suggest appropriate measure-instrument combinations for efficient soil conservation as a decision support for the implementation of soil conservation policies. Emphasis is given to the resource and institutional economics of soil conservation. In the empirical part, the efficiency of policy options is analysed using the example of a region in north-eastern Germany based on model calculations. After an introduction to the topic of soil functions and soil degradation definitions, the implementation concepts for soil protection measures at the international and national level are described. Based on the theoretical economic analysis of soils as a natural resource, the existing property rights, the public good characteristics of soils and the resulting externalities lead to the conclusion that market failure does exist. Therefore, the non-market coordination of soil use is justified. A cost-effectiveness analysis was derived based on the theory of ?safe-minimum-standard? for the appropriate assessment of the implementation options of soil conservation policies. A fuzzy-logic-based method, which is based on an expanded Universal Soil Loss Equation approach (USLE), was applied for the assessment of soil erosion risk in the sample region. The approach considers both the natural conditions and the characteristics of the cropping practice. The very detailed description of the cropping practices allowed for the specific assessment of erosion relevant effects. This, in combination with the high detail site descriptions provided this study with a very precise regional approach. The regional decision-support system MODAM (multi-objective decision support tool for agro-ecosystem management) was applied for the assessment of the economic and environmental impacts of different policy options. The policy scenarios examined include a CAP reform scenario with decoupled payments in accordance with the proposed conditions of the year 2013. This scenario was used as the reference scenario for the other possible scenarios of soil conservation policies. The three main scenarios for the policy options are 1) a non-spatially oriented, 2) a spatially-oriented incentive programmes for reduced tillage practices and 3) a regulation scenario that prohibits the cultivation of highly erosive crops (row crops) on erodible soils. The prohibition of row crops on highly erodible soils led both to lower on-farm costs and lower budget costs in comparison to the incentive programmes for reduced tillage. All three scenarios had comparable reduction in soil erosion. Based on the modeling results the ban on row crops on highly erodible sites is therefore the preferable option in terms of the cost-effectiveness ratio. The inclusion of transaction costs in this study helps expand the scope of policy analysis, for the total costs of a policy would be underestimated if only the budget costs for the direct payments to farmers were considered. Transaction costs understood as a cost for the (re-) definition and implementation of property rights can reach substantial amounts and reduce the total efficiency of a policy. The results of the qualitative analysis of the transaction costs of the study policy options also supported the option of row crop regulation on highly erodible soils. A model that serves as decision support for both the economic and agricultural aspects of soil conservation had been successfully developed in this study. Different policy options were analysed for a cost-effective solution of soil conservation programmes. Based on the final discussion on the involved transaction costs, the regulatory approach (a spatially-focussed ban on row crops) was shown to be the most cost-effective option with potentially lower transaction costs. The main criteria for a cost-effective policy design are high efficiency in both the agricultural measures (practices) and the spatial correlation between the programme area and the high erosion risk areas. Incentive programmes in combination with less effective agricultural practices showed a worse cost-benefit ratio for the sample area than the regulation approach, which is based on more effective agricultural practices.Publication Implementierung und Kosten-Nutzen-Analyse automatischer Datenerfassungssysteme in russischen Agrarholdings(2009) Andres, Silvia; Zeddies, JürgenAfter the breakdown of the Soviet Union the agricultural sector of Russia kept being dominated by large scale farms. Due to the appearance of agroholdings since 1998 this trend towards large scale farming even increased. A typical agroholding cultivates several hundred thousands of hectares on a set of numerous farms, scattered over different regions of Russia. The investors originate from the up- and downstream sectors of agriculture as well as from branches not related to agriculture. These enterprises mostly have their head offices based in Moscow. Decisions regarding investments, purchase and sales as well as production planning are centrally being made here. For an efficient management of enterprises of this size the use of information systems for decision support is indispensable. Management information systems for agriculture are less developed and have less functions than the ones developed for industrial enterprises. To realize accurate acquisition of highly resolved production data in agriculture automatic process data acquisition can be applied. Automatic process data acquisition stores data of the machinery use detailed and error-free and creates a reference to time and position for every dataset using GPS. In combination with wireless data transfer these data acquisition systems provide a unique possibility for real-time control of machinery use. Data have been collected in two agroholdings. The actual information and communication routines for documentation of the field works have been analyzed. Two systems for automatic process data acquisition have been used and evaluated. The results of the evaluation of the information systems presently implemented showed for both companies that they do not fulfill the demanded requirements for real-time availability of reliable analysis and reports. The primary documentation of field works is done exclusively on paper sheets. Further data are being processed either manually or electronically. This way of data acquisition and processing is highly susceptible to errors and easy to manipulate. Necessary information is often not available in time and not adapted to the information needs of the managers. Two systems for automatic process data acquisition to collect machinery usage data have been used on farms belonging to one of the two agroholdings: Claas-Telematics on 49 combines of the type Lexion 570 and the machinery manufacturer independent data acquisition system ODOKUS on 3 tractors. Strategies for implementation of Claas-Telematics as well as reports adapted to the needs within the specific structure of an agroholding are presented. It was necessary to create a special reporting system in order to aggregate the detailed data that are provided for every single machine to a higher level and to present meaningful key figures to the management. The weak points in the production process ?harvest? have been determined for every farm individually. The results showed that in average 1.5 - 2 hours of idle times occurred per day and machine, which could have been avoided by improved harvest organization. It could be proved that the maximum combining capacity has been used completely by only a few machines. The average wheat throughput of the combine fleet was 18,7 t/h - 30 % less than the maximum measured throughput of 26,5 t/h. The best farms considering different factors influencing high harvest productivity were determined through internal benchmarking. The manufacturer independent data acquisition system ODOKUS has been used for determining the work efficiency as well as the productivity of seeding tractors. An interface to a FMIS is already realized, thus it enables the user to perform automatized field specific data allocation and offers a possibility for complete documentation of all work processes. The analysis of work efficiency showed big differences between the three farms regarding idle times as well as productivity. In order to determine of cost effectiveness of the use of automatic data acquisition systems in Russian agroholdings the total costs of the system use as well as a Cost-Benefit analysis have been calculated for Telematics on farm and enterprise level. The savings caused by reduction of the number of third party combines, lower fixed costs due to higher workload of the machines and lower specific fuel consumption could lead to a net benefit of harvest costs of 4,83 ?/t or 1,56Mio. ? on enterprise level. These numbers represent 28 % of the total harvest costs. Within the company these systems are isolated due to lack of interfaces to other information systems used in the company. The next step should be the integration of both systems as well as the creation of a defined interface to the most important information system in the company - the accounting system. In particular the management of companies like Russian agroholdings can be provided with useful and meaningful information for decision support by the data acquisition systems considered.Publication Rentabilität und Risiko typischer Ackerbaubetriebe in der Russischen Föderation(2009) Breunig, Peter; Zeddies, JürgenConsistent world population growth, changing diets in emerging markets and the growing impact of biofuels led to considerable price increases for agricultural commodities since 2006, in particular for grains and oilseeds. Among other things this results in a growing interest of capital investors in investments in agricultural companies. Capital investments from outside the agricultural sector play ? especially in Russia ? a major role, due to the farm structure and the predominantly capital-oriented farm businesses. Until now, it is not yet clear, how these investments perform in comparison to the capital market regarding risk and return, which is critical for the future volume and sustainability of these investments. Therefore, the aim of this work is to analyze risk and return of typical arable farms in selected regions of the Russian Federation from 2000 to 2007 and make forecasts from 2008 to 2015. Additionally, the risk-return-performance of the analyzed farms is compared to a russian stock market index. This allows for the examination of the relative excellence based on risk and return among the typical farms and in comparison to the russian capital market. The evaluation of investments in arable farms in the Russian Federation based on risk and return analysis is done by two methods. The first method calculates performance ratios that are based on risk and return values of each typical farm. This is done by analyzing and forecasting financial models of the typical farms, which are based on farm surveys in the relevant regions. In total, eight typical farms in four regions (Voronesh, Stavropol, Samara and Omsk) of the Russian Federation are modeled. For the analysis of historic risk and return values, historic price and yield data from official statistics are integrated into the farm models and the relevant performance ratios are thus calculated. Future performance, price and yield data and their volatility is forecasted by using mathematical methods and published forecasts. The performance ratios of each typical farm are subsequently compared to the russian stock market index MICEX. The second method to evaluate investments in arable farms in the Russian Federation is based on the "Capital Asset Pricing Model". With this model, the return that agricultural companies in Russia have to achieve to have the same risk-return-performance as the Russian stock market can be calculated. This is done by analyzing the movement of applicable stocks relative to the total Russian stock market. Additionally investments in arable land are analyzed in the context of investments in arable farms. The results of the thesis show that in the historical period (2000 to 2007) only the typical farms in the Stavropol region are able to exceed the performance of the Russian stock market index. In the forecast period (2008 to 2015) one typical farm in the Voronesh region as well as the typical farms in the Stavropol region are expected to outperform the russian stock market. Furthermore, it can be shown that the arable farms in Samara and Omsk have a considerably lower risk-return-performance compared to the other typical farms in the west and southwest of Russia. The results validate the strong increase in investments in arable farms in the west and southwest of Russia in recent years. Moreover it is assumed that in the Samara and Omsk region similar investment volumes like in the western regions of Russia cannot be expected.Publication Entwicklung der Nahrungsmittelnachfrage und der Angebotspotenziale der Landwirtschaft in der Europäischen Union(2009) Schönleber, Nicole; Zeddies, JürgenA strong growing demand for agricultural commodities for the production of food and bio-energy led to unexpected high world prices in the past years and consequently tightened the usage competition. Shortages of fossil fuels in future will contribute to further increases of commodity prices and therefore intensify the conflict of interests. Growing food scarcity on global level will be an additional problem next to the increasing implications of climate change on agricultural production. Since several years, food demand is growing faster than food supply. The current political goals on environmental and energy issues of specific countries (EU, USA, etc.) provoke a rapid increase in demand for renewable energy sources on a global scale. Consequently these developments aggravate the usage competition for agricultural commodities. The study at hand aims to analyse the potentials of the European agriculture sector for non-food and/or export purposes. Possibly occurring competition between food and bio-energy production shall be detected and excluded from the calculation of expected developments. Accordingly the agricultural accessible area and technically feasible production potentials are analysed for the years 2000, 2010 and 2020 for all member countries of the European Union. Changes of food consumption patterns due to population development, yield increases due to improvements in plant and animal production as well as changes in utilisation of agricultural land are taken into account. Furthermore, fallow land and areas of subsidised surplus production are assumed to be potentially utilised. The results of this study show an increase of food demand for the EU-27 within the years 2000 and 2020. During these decades the per capita consumption of the EU-27 will grow by 5.4 %. Agricultural area will decrease by approx. 6.5 % until 2020. Future yields of Europe?s most important crops are expected to increase. The rise of a weighted yield of the most important crops such as cereals, oilseeds and sugar beets will on average be approx. 24 % from 2000 to 2020. Further utilisable land is expected to be released due to an improved feed utilisation in animal production and possibly by a reduction in subsidised surplus production. The resulting accessible area potential of the EU-27 can be calculated using two approaches. The first approach sums up the individual national potentials to the total potential of the EU-27. This approach assumes that no trade within the European Union is taking place. Additional demand for food has to be imported from third countries. According the first approach, the theoretical accessible land potential sums up to 27.2 million ha (approx. 14.8 % of the agricultural area) in 2020. The second approach is considering the import and export trade within the EU. Deficiencies in the supply of a country will be compensated by a surplus producer country. Therefore, it is assumed that the rate of self-sufficiency of the EU-27 concerning crops, milk and beef is 100 %. Consequently, area potentials of the EU-27 for non-food purposes decrease in comparison to the first approach. According to the calculations, an area potential of 11.5 million ha is estimated for 2020 which corresponds to approx. 6 % of the total agricultural area. In a next step, the output of the potential area of the total EU has been estimated. The production volume of the three most important crops ? cereals, oilseeds (referring to rapeseed) and tuber crops (referring to sugar beets) ? has been calculated considering the current crop ratio. Consequently approx. 14.8 million t of bio-ethanol and 1.8 million t of bio-diesel could result from the estimated crop production volumes in 2020. Referring to the amount of (fossil) fuel consumption in 2005 a share of approx. 13.1 % of motor petrol and approx. 1.0 % of diesel could be replaced. The share of bio-fuels (from domestic production) at the fossil fuel consumption would add up to 5.6 % in 2020. The results of this study show that within the timeframe investigated a strong usage competition of agricultural commodities is not expected for the European Union. Giving priority to a secure food supply within the EU offers considerable area potentials for the expansion of agricultural production for non-food purposes. Agriculture could contribute a substantial share to the targets of the EU energy policy by 2020. Nevertheless only a few member countries of the European Union (France, Germany, Ireland, Czech Republic and Hungary) have the relevant potentials and are able to achieve national energy policy objectives. At the same time fewer commodities are available for export and world food security.Publication Domestic and agricultural water use by rural households in the Oueme River Basin (Benin): an economic analysis using recent econometric approaches(2009) Arouna, Aminou; Dabbert, StephanImproving the management of water resources as well as an efficient use of available water are particularly important to address the increasing scarcity of water and the low level of water accessibility in many developing countries. However, better water management requires an understanding of the existing pattern of water use for domestic and agricultural activities. With a view towards contributing to such knowledge, this dissertation analyzes domestic and agricultural water use by rural households in the Oueme river basin of Benin. This is done within the scope of three research articles. The specific objectives of the dissertation were: 1) to analyze determinants of domestic water use in the rainy and dry seasons; 2) to estimate households? willingness to pay for water supply improvements and analyze its determinants; and 3) to quantify the efficiency of water use for agricultural production and identify factors explaining the differences in water use efficiency among households. The analyses are built on primary data collected from a household survey administrated to a sample of 325 households in the Oueme river basin, in 2007. To analyze domestic water demand, we identified three types of households: those that use only free water sources, those that use only purchased sources and those that combine both free and purchased sources. A system of two demand equations (one equation for free water and another for purchased water) was estimated using a Seemingly Unrelated Tobit (SURT) approach. The advantage of using the SURT approach is that it is appropriate to account simultaneously for the censored nature of water demand and the correlation between the error terms of two equations. In the analysis of households? willingness to pay (WTP) for water supply improvements, particular attention was given to the distribution of WTP, which has been addressed using (arbitrary) parametric assumptions in many previous studies. To avoid distributional assumptions, the dissertation introduced a semi-nonparametric bivariate probit approach to estimate WTP. To analyze water use efficiency, the dissertation combined an input-specific Data Envelopment Analysis (DEA) with a bootstrapped Tobit model. Bootstrapped Tobit takes care of the dependency problem between efficiency estimates. The analysis of water use efficiency focused on vegetable production in the dry season when water is scarce. Results showed that the average daily domestic water consumption per household during the rainy season (252 liters) is significantly higher than in the dry season (216 liters). SURT estimation results showed that water demand from purchased sources is perfectly price inelastic in the rainy season; indicating that rural households in Benin are very insensitive to changes in water price. This suggests that households are willing to pay more for water supply improvements, due not only to the necessity nature of water but also to its scarcity. Factors affecting domestic water use in the rainy season are household size and composition, education, time for fetching and accessibility to water sources. In the dry season, econometric analysis revealed that there is a positive relationship between wealth and the use of water from free and purchased sources. This result suggests that poverty reduces water use. Purchased water demand in the dry season is also perfectly price inelastic. However, a comparison of determinants of water use between seasons revealed that variables such as time for fetching water, access to water sources and wealth have differential influence on water use during the rainy and dry seasons. These results imply that policy makers must consider among other factors seasonal variation of the determinants of water use. The results of this dissertation provided the first evidence that, in rural Benin, households wanting to improve water supplies are willing to pay more than existing water prices. Households are willing to pay over one and a half times the present average water price. Furthermore, results revealed that estimated WTP would generate substantial revenue from the community, which can lead to significant reductions in subsidies. The supply of safe and adequate water based on estimated WTP will reinforce both the participation of the rural population in water supply management and the sustainability of water facilities. A related policy is that a demand-side management approach can be successfully implemented in rural areas for water supply improvements and sustainability. The important determinants of WTP for water supply improvements were education, age of household head, wealth, queue time at existing water sources and preferred improvements. The policy implication of these findings is that a combination of socio-economic factors affecting WTP, and a demand-side management approach, are likely to improve the sustainability of water projects in rural areas of Benin. Average water use efficiencies were 0.38 and 0.50 under constant and variable returns to scale specification, respectively. This implies that if vegetable farmers in the study area become more efficient in water use, significant amounts of water could be saved and made available for dry season farming land expansion. In addition, many farmers operated at an increasing return to scale (average scale efficiency is 0.70), revealing that most farms should be larger than they currently are to produce efficiently. Water use efficiency in vegetable production was determined by market access, land fragmentation, extension service, ratio of children to adults, water expenditure, water sources, off-farm income and wealth. Results suggest that policy makers should focus on improving farmers? access to input and output markets as well as their access to technical information and training through extension service or NGOs. The findings also showed that households paying for irrigation water or systems are more efficient in water use. However, any price policy should be combined with other policy options such as training and development of improved irrigation techniques adapted to socio-economic conditions of farmers. Overall, various socio-economic characteristic of households and institutional factors are found to explain water use for both domestic and agricultural activities. These factors must be carefully considered for the design and implementation of water management programs that can lead to sustainable accessibility to water. Although the research focuses on Benin, most of the conclusions and policy implications are relevant and could be applicable to many developing countries with similar socio-economics conditions. The dissertation also applies and extends recent econometric approaches that may be used for empirical studies on water management policy in developing countries.Publication Participatory evaluation of sustainability of farming systems in the Philippines(2010) Vilei, Sonja; Dabbert, StephanForest cover in the Philippines has been greatly reduced in the past and slightly recovered since, estimated at around 24% of land surface currently. Small-scale farmers have to survive on small landholdings (2 ha on average and mostly under 5 ha), face insecure land tenure, and the high population density leaves little scope for gaining new agricultural land. Their farming systems continue to form an important part of their livelihoods, but often their strategies are unsustainable in the long run. While the need for evaluating common farming systems and compare them with new alternatives exists, it is important to involve local stakeholders in the search for suitable sustainability indicators. In this study, the search was based on the Sustainable Rural Livelihoods Framework and therefore organised under its five types of capital assets: natural, financial, physical, human and social capital. Farmers from five study sites along the Western side of the island of Leyte were gathered in eight focus group discussions to discuss the issues of success and sustainability of their farming systems and identify and rank possible criteria for an evaluation of sustainability. Nine other stakeholders from the same sites were interviewed individually. In a second research phase, all 49 identified criteria were given to 30 farmers and 18 other stakeholders for ranking. Three groups of farmers from the municipality of Baybay were used for comparison: one group of rice and coconut farmers; a second group with (additional) exotic timber trees (usually Gmelina and Acacia mangium); a third group with (additional) indigenous timber trees (?Rainforestation Farming?). The identified indicators were tested regarding their usefulness for comparing the three groups of farmers. Rainforestation Farming, as promising alternative farming system, was analysed further regarding financial aspects and its adoptability with regard to small-scale farmers. The Sustainable Rural Livelihoods Framework was useful for identifying suitable evaluation criteria. The importance of the five capital assets groups was perceived similarly by farmers and other stakeholders, but ranking results for single criteria (i.e. soil quality, membership in organisation) differed. The same holds true when comparing results for the four study regions, where the individual ranking was carried out: significant differences existed for single, mostly financial, criteria (i.e. record-keeping, investment costs) but not for importance of the five capital asset groups. The ranking results differed quite substantially, though, between focus groups and individual farmers, indicating on the one hand the influence of group leaders. But, on the other hand, farmers had the complete list of criteria for the individual ranking, including several criteria which they had not thought of previously, but which they still regard as important. Fifteen criteria were selected as indicators for comparing the three farmers groups. Rainforestation farmers were the group scoring significantly higher on most indicators (i.e education level adults and children, land available per capita, (perceived) soil quality, number of soil conservation measures used, membership in organisation) than farmers without timber trees. Farmers having planted exotic timber trees scored closer to Rainforestation farmers. But to be able to judge if the specific farming system leads to a more sustainable livelihood, time series data would have been necessary. The data of this study allowed concluding that tree farmers planting (indigenous or exotic) timber trees are endowed with higher resources ? more land, higher income, higher education levels. Most likely they had these resources before starting their farming systems. In addition, these farmers were also more actively engaged in organisations and had more contact to extension agents, therefore enhancing their social (and human) capital. The higher score regarding (perceived) soil quality and (non-) use of pesticides these farmers groups reached are likely to be an outcome of the farming system practiced. Analysing the financial feasibility and adoptability of Rainforestation Farming, it shows that the system has the potential to be profitable, but coming with a high risk: investment costs are very high and it takes up to 13 years to regain them. Consequently, the first adopters either had unused land areas or substantial off-farm income, and the subsequent adoption rate is low. Sustainability has to be understood as a dynamic and not a static concept and the concept of sustainable land management must consequently evolve as well. This study tried to add further findings regarding the use of suitable methods for this cause, but as already mentioned above, time series data would be necessary to assess the progress of farming systems towards ?sustainability?.