10 research outputs found

    MÖGLICHKEITEN UND GRENZEN DER POLITIKANALYSE ZUR UMSETZUNG DER WASSERRAHMENRICHTLINIE -- ANWENDUNG EINES HYDRO-ÖKONOMISCHEN MODELLVERBUNDES FÜR DAS WESER EINZUGSGEBIET

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    EU-Wasserrahmenrichtlinie, landwirtschaftliche Einträge in die Gewässer, hydroökonomische Modellierung, RAUMIS, kosteneffiziente Maßnahmen, Agricultural and Food Policy, Environmental Economics and Policy, Land Economics/Use,

    Agri‐Environmental Policy in Poland: Challenges and Evaluation Approaches

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    The main objective of the paper is to investigate challenges for the agri‐environmental policy in Poland and to detect methodical approaches which can be used for the evaluation and design of agrienvironmental measures to make them more effective. Analysing the development of the agri‐environmental policy in the transformation process in Poland, before and after the accession to the European Union, we state that several changes are necessary to improve the efficiency and effectiveness of agri‐environmental measures in Poland. The acknowledged methodical approaches can be helpful to evaluate agri‐environmental measures and to specify problems to be solved in the following years

    Agricultural costs for reducing nitrogen surpluses in the Weser river basin

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    Agriculture is to a large part responsible for nitrate leaching into groundwater and rivers in Germany, especially in highly intensive agricultural regions. To evaluate the link between nitrogen surpluses from agriculture and nutrient leaching into ground- and surface waters, a model network to analyse current and future nitrogen surplus developments and water quality is set up by connecting hydrological and hydrogeological models with the German agricultural sector model RAUMIS. A set of different environmental measures and their costs is selected to fulfil surface and groundwater targets of the European water framework directive (WFD) for the case of the Weser River basin. Results show that with additional agri-environmental measures covering around 1 million hectares agriculturally used land with total costs of 100 million Euros the objectives of the WFD could be achieved until 2015. Sensitivity analysis allows a better valuation of the range of the costs. The costs and volumes are compared to regional farming characteristics and subsidies. Results show that costs of additional environmental measures would take up 5% of current direct payments to farmers. The work represents an interdisciplinary area wide modelling approach to evaluate agricultural input and measures together with an approach to quantify costs to achieve environmental objectives of the WFD.diffuse pollution / agricultural economic and hydrological modelling / cost of nutrient reduction measures / Weser river basin, Agricultural and Food Policy, Crop Production/Industries, Farm Management, Land Economics/Use, Production Economics,

    RECENT DEVELOPMENTS IN EU POLICIES – CHALLENGES FOR PARTIAL EQUILIBRIUM MODELS

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    This paper gives an overview on current and prospective modelling challenges for agricultural partial equilibrium (PE) models focussing on EU policies. Starting from a certain policy context, the paper highlights the current capabilities and limitations of existing PE models and, if available, develops some ideas on future modelling directions to advance the usefulness of quantitative information provided.Policy impact assessment, agricultural partial equilibrium models, Common Agricultural Policy, Agricultural and Food Policy, Research Methods/ Statistical Methods,

    Model based impact analysis of policy options aiming at reducing diffuse pollution by agriculture - a case study for the river Ems and a sub-catchment of the Rhine

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    In this paper an integration of the agricultural economic model RAUMIS with the hydrological models GROWA98 and WEKU is presented. The focus lies on an area wide, regionally differentiated, consistent link-up between the indicator "nitrogen balance surplus" and nitrogen charges into surface waters. The model network is used to analyze the status quo situation in the year 1999 for two river catchments in Germany that feature very distinct natural and socio-economic conditions. Regarding agriculture, the study areas include regions with specializations in cash crops, in intensive livestock featuring high nitrogen surplus, and extensive livestock production on permanent grassland. Due to regionally varying hydrological conditions quite different shares of agricultural nitrogen surpluses ranging from 25 to 92% enter surface waters. Furthermore, impacts of alternative nitrogen reduction measures namely a limitation of livestock density and a tax on mineral nitrogen are quantified. Measures of the nitrogen reduction potential and costs in terms of agricultural income forgone are taken into account in the assessment. Results regarding the effects of restricting the livestock density or tax mineral nitrogen highlight that the mitigation of diffuse water pollution problems requires regionally tailored measures. (C) 2004 Elsevier Ltd. All rights reserved

    Hydrodynamics and Morphology in the Ems/Dollard Estuary: Review of Models, Measurements, Scientific Literature, and the Effects of Changing Conditions

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    The Ems estuary has constantly changed over the past centuries both from man-made and natural influences. On the time scale of thousands of years, sea level rise has created the estuary and dynamically changed its boundaries. More recently, storm surges created the Dollard sub-basin in the 14th -15th centuries. Beginning in the 16th century, diking and reclamation of land has greatly altered the surface area of the Ems estuary, particularly in the Dollard. These natural and anthropogenic changes to the surface area of the Ems altered the flow patterns of water, the tidal characteristics, and the patterns of sediment deposition and erosion. Since 1945, reclamation of land has halted and the borders of the Ems estuary have changed little. Sea level rise has continued, and over the past 40 years the rate of increase in mean high water (MHW) along the German coast has accelerated to 40 cm/ century. Climate has varied on a decadal time scale due to long-term variations in the North Atlantic Oscillation (NAO), which controls precipitation, temperature, and the direction and magnitude of winds. Between 1960 and 1990 the most intense variation in the NAO index on record was observed. As a result the magnitude and frequency of storm surges increased, and mean wave heights increased at 1-2 cm/year. Currently the NAO index—and therefore storminess—is trending downwards. Over the longer term, global warming models predict an average temperature rise of 2 degrees Celsius over the next century. A doubling of CO2 is expected to increase sea level by 30 cm, while the significant wind speed and wave heights in the North Sea are predicted to increase by 50 cm/s and 50 cm, respectively. Beginning in the late 1950’s, dredging activity and construction measures in harbours and shipping channels greatly altered the physical processes in the Ems. Deepening and streamlining the Ems River and shipping channel between the 1960s and 1990s decreased the hydraulic roughness and increased the tidal range in the river above Emden by as much as 1.5 m. At the turbidity maximum between Emden and Papenburg, concentrations of sediment are currently between 1-2 orders of magnitude larger than in the 1950’s, and fluid mud layers of several meters thickness occur. Other man-made changes, such as gas pipelines and the expansion of harbours, have often caused significant, but more localized, changes to the estuary. Between the mid 19th century and the 1970’s, dumping of organic waste—agricultural, industrial, and human—severely stressed the ecology of the Dollard sub-basin in particular. Since then the input of organic waste has been greatly reduced and anoxic conditions eliminated. However, the increase in turbidity at the turbidity maximum has caused depleted oxygen concentrations and periodic anoxia between Pogum and Papenburg during the summer months (personal communication, H. Juergens; Talke et al, 2005). The Ems is a relatively well studied estuary. Significant research projects have included the BOEDE project in the 1970’s --1980’s and the BOA and INTRAMUD projects in the 1990’s. These projects and other efforts have amassed a deep literature in the knowledge of tidal flats, fluid mud and flocculation, and mixing and dispersion processes. Projects currently underway are focusing on tidal dynamics and the affects of dredging in the high turbidity zone between Emden and Herbrum. Optimal management of the estuary is the goal of the HARBASINS project. Many analytical and numerical models have been applied to the Ems estuary to estimate tidal range, storm surges, wave fields, sediment transport, and mixing and dispersion processes. Analytical models to estimate mixing of scalars and sediment fluxes (Sediment Trend Analysis) have been extensively used. Numerical models such as WAQUA, unTRIM, MIKE3, Telemac 2D, SWAN, Delft 3D –Sed, and others have been applied to the Ems. While reasonable results are found for short term processes (order of days), long-term morphological change cannot yet be predicted. For the Ems catchement basin, the numerical models REGFLUD and FLUMAGIS are used to estimate nutrient inputs from diffuse sources and to visualize and evaluate the effects of land-use change

    Modelling Regional Maize Markets for Biogas Production in Germany : The Impact of Different Policy Options on Environment and Transport Emissions

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    The production of biogas is considered to be a promising candidate for a sustainable energy mix. Accordingly, Germany’s Renewable Energy Act (EEG) promotes electricity production from biogas along with other renewable energies. While overall benefits are seen in terms of climate protection and increased employment in rural areas, for example, biogas production (mainly from maize in Germany) also has the potential to create negative environmental effects on a regional scale. This can be caused by the production of monocultures and increasing transport volumes, to cite two prominent examples. To assess environmental effects arising from bioenergy policies, different types of agricultural models have been applied to determine the effects on competition for primary factors. Generally, these models do not however capture the demand side for crops with high transportation costs such as maize. The production of biogas is considered to be a promising candidate for a sustainable energy mix. Accordingly, Germany’s Renewable Energy Act (EEG) promotes electricity production from biogas along with other renewable energies. While overall benefits are seen in terms of climate protection and increased employment in rural areas, for example, biogas production (mainly from maize in Germany) also has the potential to create negative environmental effects on a regional scale. This can be caused by the production of monocultures and increasing transport volumes, to cite two prominent examples. To assess environmental effects arising from bioenergy policies, different types of agricultural models have been applied to determine the effects on competition for primary factors. Generally, these models do not however capture the demand side for crops with high transportation costs such as maize. Coupling ReSI-M with RAUMIS, a partial supply model which depicts German agriculture based on regionally differentiated processes, adds regional market clearing for a robust impact assessment of biogas production. As a result, policy implications on land use of different policy settings are analysed in this thesis. Furthermore, ReSI-M simulates regionally differing CO2 emissions from transports per kWhel (kilowatt hour electric), as well as the efficiency of subsidies for the policy scenarios. The results show that adding maize demand to an assessment of land use changes improves the representation of regional maize markets since regional demand characteristics such as transport costs and availability of inputs are taken into account. Simulation results indicate that under a scenario adopting feed-in tariffs according to the EEG 2004, less land for maize cultivation per kWhel is used and also less transport emissions are caused compared to the EEG 2008 and the counterfactual scenario. Furthermore, results point out differences in regional maize markets under the applied scenarios: under the EEG 2008 scenario, maize production increases in regions with high livestock densities, which therewith further intensifies maize production in regions where the production level is already high. Applying the counterfactual scenario shows that production increases in regions with low transport costs. However, under the EEG 2008 the greatest amount of energy from biogas is produced and most subsidies per produced kWhel are paid. The efficiency of subsidies is best in the counterfactual scenario, in which feed-in tariffs are paid independent of plant size and technology. Against these results, the thesis concludes with policy recommendations and suggestions for further research. The work provides a tool for policymakers to evaluate distinct regional demand levels for maize and its environmental impacts while the work also contributes to an ongoing political debate of the benefits and drawbacks of bioenergy production.Modellierung regionaler Maismärkte zur Biogasproduktion in Deutschland - Der Einfluss verschiedener Politikoptionen auf die Umwelt und Transportemissionen Die Produktion von Biogas wird als vielversprechende Option innerhalb eines nachhaltigen Energiemixes angesehen, und dementsprechend wird in Deutschland die Produktion von Biogas zusammen mit anderen erneuerbaren Energien durch das Erneuerbare-Energien-Gesetz (EEG) gefördert. Während Vorteile für den Klimaschutz und ländliche Entwicklung gesehen werden, birgt die Produktion von Biogas (in Deutschland hauptsächlich auf der Basis von Silomais) die Gefahr, negative Umwelteffekte wie beispielsweise den Anbau von Mais in Monokulturen und steigende Transportaufkommen auf regionaler Ebene zu verursachen. Zur Bewertung von Umwelteffekten, die durch unterschiedliche Bioenergiepolitiken entstehen, wurden verschiedene agrarökonomische Modelle angewandt, um Auswirkungen auf den Wettbewerb von Einsatzfaktoren zu erfassen. Diese Modelle bilden die Nachfrageseite von Pflanzen mit hohen Transportkosten, wie beispielsweise Silomais, jedoch nicht ab. Basierend auf der Standorttheorie und vor dem Hintergrund bestehender Standortmodelle, wird im Laufe der Dissertation ein neues Modell entwickelt, um Standorte und Größen von Biogasanlagen zu bestimmen und somit deren Maisnachfrage abzuleiten. Das Standortmodell ReSI-M (Regionalsiertes Standortinformationsmodell – Mais) ermöglicht es regionale Nachfrage-funktionen für Silomais als eine Funktion von Silomaispreisen und weiteren Erklärungsvariablen wie Transportkosten und wirtschaftliche Profitabilität von verschieden Biogasanlagentypen abzuleiten. Es simuliert Nachfragefunktionen für drei Politikszenarien: das EEG 2004, das EEG 2008 mit entsprechenden Einspeisevergütungen, und außerdem ein fiktives Szenario („counterfactual scenario―), in dem Einspeisevergütungen unabhängig von Anlagengröße und –technologie gezahlt werden. Das letzere Szenario wird angewandt, um die EEG Szenarien mit einer Situation zu vergleichen, in welcher die resultierende Anlagenstruktur theoretisch einer kostenminimalen Lösung entspricht. Durch das Koppeln von ReSI-M mit RAUMIS, einem partiellen Angebotsmodell, das den deutschen Agrarsektor regional differenziert abbildet, wird eine regionale Markträumung einer Folgenabschätzung der Biogasproduktion hinzugefügt. Somit werden in dieser Dissertation Politikauswirkungen auf Landnutzung und resultierende Umwelteffekte analysiert. So werden mit ReSI-M regional unterschiedliche CO2 Transportemissionen pro kWhel (Kilowattstunden elektrisch) und die Effizienz von Subventionen für die Politikszenarien simuliert. Die Ergebnisse zeigen, dass eine Ergänzung der Maisnachfrage innerhalb einer Bewertung von Landnutzungsänderungen, die Abbildung von regionalen Maismärkten verbessert, da regionale Charakteristika auf der Nachfrageseite, wie Transportkosten und die Verfügbarkeit von Einsatzstoffen, berücksichtigt werden. Simulationsergebnisse weisen darauf hin, dass unter dem EEG 2004 Szenario die geringste Landfläche pro kWhel benötigt wird und weniger Transportemissionen im Vergleich zu dem EEG 2008 und dem fiktiven Szenario verursacht werden. Zudem stellen die Ergebnisse Unterschiede der regionalen Maismärkte bei den verschiedenen Szenarien heraus: unter dem EEG 2008 Szenario steigt die Maisproduktion vor allem in Regionen mit einer hohen Viehdichte an und verstärkt somit den Maisanbau in Regionen, wo er für den Futteranbau bereits hoch ist. Die Anwendung des fiktiven Szenarios zeigt, dass sich die Produktion in Regionen mit geringen Transportkosten ausdehnt. Dabei handelt es sich vornehmlich um Ackerbauregionen. Unter dem EEG 2008 wird jedoch die meiste Energiemenge produziert und die meisten Subventionen pro kWhel gezahlt. Die Effizienz der Subventionen ist hingegen im fiktiven Szenario am besten. Vor dem Hintergrund dieser Ergebnisse, schließt diese Dissertation mit Politikempfehlungen und Vorschlägen für weiteren Forschungsbedarf. Die Arbeit stellt ein Instrument für Entscheidungsträger vor, das dabei hilft, unterschiedliche regionale Maismärkte und deren Umwelteffekte zu bewerten und trägt somit zu der aktuellen politischen Debatte über die Vor- und Nachteile der Förderung von Bioenergie bei

    A hydro-economic modeling framework for optimal management of groundwater nitrate pollution from agriculture

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    La contaminación difusa por nitratos de las aguas subterráneas, la cual es principalmente originada por la agricultura, es una creciente preocupación en casi cualquier parte del mundo. Esto ha provocado el desarrollado de normativas; en Europa, en 1991 se estableció la Directiva de Nitratos y el año 2000 la Directiva Europea Marco del Agua (DMA). La DMA establece que las masas de agua deben alcanzar el buen estado en el año 2015, además reconoce el rol que la economía puede tener en alcanzar los objetivos ecológicos y ambientales. En este trabajo se presenta un modelo hidro-económico que sugiere la gestión óptima de fertilizantes para controlar la contaminación por nitratos de las agua subterráneas. El modelo holístico de optimización determina la distribución espacio-temporal de la tasa de aplicación de fertilizantes que maximiza los beneficios netos en la agricultura, limitada por los requerimientos de calidad en el agua subterránea en diferentes puntos de control. El modelo relaciona la aplicación de fertilizantes con las concentraciones de nitratos en el agua subterránea mediante el uso de modelos agronómicos, de simulación del flujo y transporte en el agua subterránea, con los cuales se generan soluciones unitarias que son integradas en matrices de respuesta (RM). Las RM dentro del modelo de gestión permiten simular la evolución de la concentración de nitratos en el agua subterránea mediante superposición en diferentes puntos de control a largo del tiempo, debido a la emisión de contaminantes en diferentes zonas distribuidas en el espacio y variables en el tiempo. Los beneficios de la agricultura se determinan a través de funciones de producción y el precio de los cultivos. El modelo desarrollado se aplicó a un acuífero sintético. Se obtuvo la aplicación óptima de fertilizantes para problemas con diferentes condiciones iniciales, horizontes de planeación y tiempos de recuperación.Peña Haro, S. (2010). A hydro-economic modeling framework for optimal management of groundwater nitrate pollution from agriculture [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/7483Palanci

    Wasser qualität Bewertung und Verwaltung von Flachland Fluss Einzugsgebiet

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    This dissertation describes at first the hydrology and the long-term impact of point and diffuse source pollution on nutrient loads based on the current agricultural practices and sewage disposals in rural lowland catchments. The evaluations of Best Management Practices (BMPs) for water quality improvement was then implemented aiming at controlling and reducing pollution from point and diffuse sources in the entire catchments.Diese Dissertation beschreibt zunächst die Hydrologie und die langfristigen Auswirkungen von Punkt- und diffusen Quellen auf die Nährstoffbelastungen, die auf den derzeitigen landwirtschaftlichen Praktiken und Abwassereinleitungen in ländlichen Tiefland-Einzugsgebieten basieren. Bewertungen von Best Management Practices (BMPs) für die Verbesserung der Wasserqualität wurden dann mit dem Ziel der Kontrolle und Verringerung der Umweltverschmutzung aus Punkt- und diffusen Quellen in gesamten Einzugsgebieten durchgeführt

    Análise de consistência dos parâmetros do modelo swat obtidos por calibração automática – estudo de caso da bacia do lago descoberto - DF

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    Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Civil e Ambiental, 2014.A modelagem hidrológica pode auxiliar a compreensão dos processos físicos e a avaliação dos impactos nos recursos hídricos e no meio ambiente, advindos principalmente do desenvolvimento rural e da expansão urbana em bacias hidrográficas. No entanto, a modelagem de um sistema requer etapas indispensáveis para a obtenção de resultados coerentes com a realidade, confiáveis e de qualidade. Considerando essa problemática, o objetivo deste trabalho foi avaliar a representatividade dos parâmetros do modelo hidrológico SWAT (Soil and Water Assessment Tool) obtidos por calibração automática das vazões de uma bacia hidrográfica, para utilização em outras cinco bacias que contribuem para o lago Descoberto no Distrito Federal, analisando conjuntamente a simulação da dinâmica hidrológica. Foi realizada a análise de sensibilidade do modelo a 14 parâmetros escolhidos pelo grau de importância durante a simulação inicial do modelo e pelas dificuldades observadas no processo de simulação das vazões. A calibração dos parâmetros em nível diário para os anos hidrológicos de 2005 a 2010 para a sub-bacia do rio Descoberto (SBRD) foi considerada satisfatória, tendo sido obtido um coeficiente de eficiência de Nash-Sutcliffe (NSE) de 0,4 e um coeficiente de determinação (R²) de 0,44. Na verificação, para o período de 2010 a 2013, obteve-se um NSE de 0,48 e um R² de 0,46. Na SBRD, durante os anos hidrológicos de 2005 a 2010, os erros percentuais entre os valores das vazões observada e simulada, nas estações de chuva e seca, foram respectivamente de 35% e 56%, o que evidenciou que o modelo apresentou maiores dificuldades na simulação do fluxo de base durante o período de estiagem. A verificação da representatividade dos parâmetros calibrados automaticamente para a SBRD em nível mensal foi considerada satisfatória para outras quatro sub-bacias. Apenas a sub-bacia do córrego Olaria não apresentou resultados estatísticos satisfatórios. Os valores obtidos nas simulações para os componentes do ciclo hidrológico foram coerentes com trabalhos experimentais anteriores. Em relação à recarga ao aquífero raso, a diferença entre o observado e o simulado foi de 4,23% na sub-bacia do córrego Capão Comprido (SBCCC). A simulação da carga de sedimentos foi ruim, pois a modelagem levou a apenas 37,4% da carga total de sedimentos medida na SBCCC. Esses resultados mostraram a importância da escolha de parâmetros determinantes para o estudo, além da viabilidade do uso dos parâmetros obtidos por calibração automática em bacias hidrográficas similares. _______________________________________________________________________________________ ABSTRACTHydrological modeling can help the understanding of physical processes and assessment of impacts on water resources and the environment caused by rural development and urban expansion in watersheds. However, modeling water systems requires essential steps for obtaining consistent and reliable results. This study aims to evaluate the representativeness of parameters hydrological model SWAT (Soil and Water Assessment Tool) obtained by automatic calibration of the surface flow from a watershed, for use in other five wathershed that contribute to the Descoberto Lake in the Federal District, including the analysis of hydrological dynamics simulation. Sensitivity analysis of the model was performed for 14 parameters chosen by degree of importance during the initial simulation and the observed difficulties in simulating the flows. The parameter calibration at daily basis for the hydrological years 2005 to 2010 for the River Descoberto (SBRD) was satisfactory. It led to a Nash-Sutcliffe efficiency (NSE) of 0.4 and a coefficient of determination (R²) of 0.44. The validation for the period 2010 to 2013 led to NSE of 0.48 and a R² of 0.46. The percentage errors between the observed and simulated flow values in SBRD during the hydrological years of 2005 to 2010, were 35% and 56% at the rainy and dry seasons, respectively. It was found difficulties to simulate the base flow during the dry season. The validation of the representativeness of the parameters automatically calibrated for SBRD at monthly basis were satisfactory for other four sub-basins. The study found non-satisfactory statistical results only for Olaria Creek. The values obtained in the simulations of hydrological cycle components were consistent when compared to previous experimental works. Concerning to the shallow aquifer recharge, the difference between observed and simulated data was 4.23% for Capão Comprido Creek sub-basin (SBCCC). The simulation of sediment load was not good considering that it led to only 37.4% of the total sediment loads, measured in SBCCC. These results show the importance of the parameters selected for the study, and the feasibility of use of parameters obtained by automatic calibration in similar watersheds
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