L'objectif initial de cette thèse est d'apporter une solution à ce problème en proposant, premièrement, une approche cognitive basée sur le paradigme appelé Belief-Desire-Intention (BDI) pour représenter les processus de prise de décision des acteurs humains, et deuxièmement, une validation de cette approche dans le contexte d'un modèle complet de changement d'usage des sols dans lequel la plupart des facteurs cités ci-dessus sont également simulés. Le résultat de ce travail est une approche générique qui a été validée sur un modèle intégrant le changement d'usage des sols d'une région située dans le Delta du Mékong au Vietnam. Nos contributions principales sont les suivantes : Intégration d’une architecture BDI au sein d'une plateforme de modélisation à base d'agents (GAMA) ;Conception d’un cadre générique baptisé « Multi-Agent Based Land-Use Change » (MAB-LUC) permettant de modéliser et de simuler les changements d’usage des sols en prenant en compte les décisions des agriculteurs ;Proposition d’une solution permettant d’intégrer et d’évaluer les facteurs socio-économiques et environnementaux dans le cadre de la planification agraire et d’intégrer MAB-LUC dans le processus existant proposé par la FAO.Ce travail, au-delà du cas d’étude concernant le Delta du Mékong, a enfin été conçu de façon générique afin que la méthodologie utilisée puisse être généralisée à la modélisation de systèmes socio-écologiques où les facteurs humains doivent être représentés avec précision. / The initial goal of this thesis has been then to address this problem by proposing, on one hand, a cognitive approach based on the Belief-Desire-Intention (BDI) paradigm to represent the decision-making processes of human actors in agent-based models and, on the second hand, a validation of this approach in a complete land-use change model in which most of the factors cited above have also been simulated.The outcome of this work is a generic approach, which has been validated in a complex integrated land-use change model of a small region of the Vietnamese Mekong Delta. Our main contributions have been:The integration of the BDI architecture within an agent-based modeling platform (GAMA); The design of the Multi-Agent Based Land-Use Change (MAB-LUC) framework that can take into account the farmers’ decision-making in the land-use change processes;The proposal of a solution to assess the socio-economic and environmental factors in land-use planning and to integrate the MAB-LUC framework into the land-use planning process of. I conclude by showing that this work, designed in a generic fashion, can be reused and generalized for the modeling of complex socio-ecological systems where individual human factors need to be represented accurately.

No description available.

Flooding has been identified as the most widespread and most frequently occurring natural disaster by the United Nation. Sweden is no exception when it comes to being affected by flooding, and several major flood events have been seen in recent years. The Swedish National Board of Building, Housing and Planning published a report on climate adaption in 2010 where they stated that Sweden is missing over all strategies and goals meet the demands of more frequent and intense rain events. Present thesis aimed to develop planning support for integration of hydrological perspectives in urban planning to manage water related risks such as flooding and high water levels. This was done through hydrodynamic modelling in MIKE FLOOD, developed by the DHI, where a 1D stream model was coupled with a 2D free-surface flow model. The model was run for three different scenarios reflecting current conditions (Scenario 1), climate change (Scenario 2) and land use change (Scenario 3). The study area chosen for present study was Kista residential area, located northwest of Stockholm, and part of Igelbäcken stream that runs by Kista. Igelbäcken stream was represented by a 1D stream model in the software MIKE 11 provided by DHI and Järfälla municipality, whereas a 2D model in MIKE 21 for Kista and the stream surroundings was setup throughout the project. Data was provided by Stockholm Vatten och Avfall and processed in ArcMap before it could be used in the modelling. The MIKE 21 model required data regarding topography, land use, and precipitation. A 100-year flood, based on a series of designed rain events with various duration and intensity, was used as precipitation input to replicated a hypothetical major rain event. Flooding in Scenario 2 was more extensive than flooding in Scenario 1, which was expected since Scenario 2 was based on a 100-year flood with a climate change factor of 1.25 and projection for year 2100. Scenario 3, which represented a “worst case” scenario with all planned exploitation of Kista identified as impermeable surface, forced the water to move further down in the topography compared with Scenario 1. Several buildings were more or less surrounded by at least 0.3 meter of water in Scenario 3. Water levels in Igelbäcken stream were strongly affected by the rain events and showed an increase of 0.4, 0.9, and 0.4 meter for the three scenarios at the end of the simulations which lasted for six hours. In conclusion, findings of present study show larger flooding extent that previously performed studies in the area and they reflect fast response in Igelbäcken stream with respect to increased water level. Indicating that effects from major rain events should not be underestimated. Furthermore, the findings could prove useful for identification of major runoff pathways and identification of suitable locations for multifunctional with respect to infiltration and retardation, if available at an early stage in the planning process. Thus, this type of study could prove useful for integration of hydrology in the urban planning process. / Översvämningar har identifierats som världens mest utspridda och vanligast förekommande naturkatastroftyp av FN. Sverige är inget undantag när det kommer till påverkas av översvämningar, under de senaste åren har flera stora översvämningar förekommit i landet. Boverket publicerade 2010 en rapport gällande Sveriges hantering av klimatanpassning. Slutsatsen av denna rapport var att övergripande strategier och mål för klimatanpassning saknas när det gäller hantering av kraftiga skyfall och att bättring krävs för en hållbar samhällsutveckling. Denna studie syftade till att utveckla planeringsstöd för integrering av ett hydrologiskt perspektiv i urban planering för att hantera vattenrelaterade risker så som översvämning och höga vattennivåer. Detta gjordes genom hydrodynamiks modellering i mjukvaran MIKE FLOOD, utvecklad av DHI, där en 1D vattendragsmodell kopplades till en 2D ytavrinningsmodell. Modellen kördes för tre scenarion: nuläget (Scenario 1), klimatförändring (Scenario 2) och förändrad markanvändning (Scenario 3). Förorten Kista, belägen nordväst om Stockholm, och den del av Igelbäcken som passerar Kista valdes som studieområde. Igelbäcken representerades av en 1D vattendragsmodell, MIKE 11, som tillhandahölls av DHI, medan en 2D ytavrinningsmodell i MIKE 21 sattes upp för Kista och Igelbäckens omgivning under projektets gång. Data tillhandahölls av Stockholm Vatten och Avfall och bearbetades i ArcMap innan den kunde användas i modelleringen. MIKE 21 modellen baserades på data rörande topografi, markanvändning och nederbörd. Ett 100-års regn, baserat på en serie möjliga 100-års regn med varierande intensitet och varaktighet, användes som nederbördsdata för att efterlikna ett hypotetiskt kraftigt skyfall. Översvämning i Scenario 2 hade en större utbredning än Scenario 1, vilket var väntat då Scenario 2 baserades på ett 100-års regn med en klimatförändringfaktor på 1.25 och en klimatprojektion för år 2100. Scenario 3, vilket representerade ett ”värsta möjliga” scenario med all planerad exploatering i Kista definierad som icke genomsläpplig yta, tvingade vatten som ansamlats på ytan att röra sig längre ner i topografin eller fångade det på nya ställen i studieområdet jämfört med Scenario 1. Ett flertal byggnader var till stor del omringade av ett vattendjup på åtminstone 0.3 meter i Scenario 3. Vattennivåer i Igelbäcken var inledningsvis väldigt låga, men påvisade sedan en ökning av 0.4, 0.9 samt 0.4 meter i respektive scenario vid simuleringens slut (vilken varade i sex timmar). Sammanfattningsvis påvisade studien större översvämningsspridning än tidigare genomförd översvämningsmodellering i området. Vidare visade resultaten en snabb respons i Igelbäcken med avseende på vattennivåförändringar vid simuleringens slut. Detta indikerar att påverkan från kraftiga skyfall inte bör underskattas. Resultaten ses som användbara i ett tidigt stadie av planeringsprocessen för identifiering av viktiga ytavrinningsvägar i landskapet samt för lokalisering av lämpliga ytor för etablering av multifunktionella ytor, till exempel parker, med avseende på infiltration och fördröjning av dagvatten. Denna typ av studie kan därmed ses som användbar för integration av ett hydrologiskt perspektiv i den urbana planeringsprocessen.

As the global population continues to grow, urbanization is one of the most significant anthropogenic processes linked to ecological change. But even in countries where the overall population is stagnating, migratory movements toward urban centres will continue to place pressure on the finite resource of land. Therefore, it is particularly important to determine and describe the development of settlement areas as precisely as possible in order to inform spatial planning decisions. For this reason, this dissertation presents vector-based methods to analyse, quantify and evaluate small-scale changes in settlement area. In this work, which constitutes a cumulative dissertation, novel methods are described that can be used to determine not only areal change in settlement and traffic areas (SuV), but also the type of building change and urban densification. This is of particular interest for the spatial planning of expanding metropolitan areas, where the question arises: Where, how and to which extent can built-up areas be further densified in order to reduce the consumption of land for new settlement areas? The methods presented here can facilitate spatially detailed analyses and already form the basis for a nationwide monitoring of settlement and open space development. This work shows how geometric deviations and changes in the underlying data model can be taken into account when determining SuV growth from data of the Authoritative Topographic-Cartographic Information System (ATKIS). In this context, positional inaccuracies of linearly and arealy modelled geometries are each treated in a special way so that minor positional offsets no longer affect the SuV increase. In addition, changes in the data model are accommodated by disregarding specific object reallocations when determining the SuV increase. To test these methods, the SuV increase was determined and analysed for Germany using national ATKIS data sets that feature geometric positional inaccuracies and data model changes. It could be shown that a considerable share of the calculated SuV increase is not due to real-world changes but to modelling issues. Furthermore, a novel method for the detection of building changes is presented, which focuses on the differentiation between modified and replaced buildings. It could be shown that this new approach is more accurate than other investigated methods. Furthermore, an algorithm was developed in this work to generate defined location deviations. This could be used to show how position deviations affect the accuracy of the examined procedures. The threshold values determined in this work can form the basis for similar investigations. In addition, an indicator was developed to track changes in building density. This indicator not only reflects the extent of building change but also the size of the existing building stock. Moreover, the indicator was designed in such a way as to allow comparison of the densification of developed and undeveloped areas, and thus also inner and outer urban areas. Furthermore, the indicator can be used to symmetrically calculate a decrease in the building stock, enabling a comparison of densification and de-densification processes.:1. Introduction 1.1 Motivation 1.2 Problem description 1.3 Aims 1.4 Structure 2. Dissertation main articles 2.1 Measuring land take in Germany 2.2 Detecting building change 2.3 Indicator for building densification 3. Methods for measuring settlement changes 3.1 Measuring changes through land use data 3.2 Detection of building changes 3.3 Measuring changes in building density 4. Main findings 4.1 Effects of non-real changes on land take 4.2 Distinguishing building modification and replacement 4.3 Impact of building changes on building density 4.4 How the articles are connected 4.5 Additional relevant publications 5. Conclusion and Outlook References Abbreviations List of figures List of author’s publications Articles Conference Papers Acknowledgments Appendix with publications

Landnutzungswandel ist eine der Hauptursachen von Biodiversitätsverlust. In den Tropen und Subtropen führt eine Ausweitung von Agrarflächen zu vermehrter Abholzung der Wälder. Selbst wenn zukünftige Waldrodungen vermieden werden können, ist ein weiterer Artenrückgang sehr wahrscheinlich, da viele Arten zeitverzögert auf Veränderungen reagieren. Die Hauptziele dieser Arbeit waren die Auswirkungen vergangener und aktueller Landnutzung auf Biodiversität im argentinischen Chaco besser zu verstehen und Ansätze zu entwickeln, um negative Effekte schon vor einem lokalen Aussterben zu erkennen. Der argentinische Chaco ist aufgrund seiner Landnutzungsgeschichte, den hohen Abholzungsraten und der hohen Biodiversität bestens für eine solche Untersuchung geeignet. Meine Arbeit zeigt, dass der Artenreichtum an Vögeln und Säugetieren stark durch vergangene Landschaftsmuster beeinflusst wurde, was auf zeitverzögerte Reaktionen auf Landnutzungswandel hindeutet, sowie darauf, dass ein Teil der momentan vorkommenden Arten durch vergangene Landnutzungsänderungen noch aussterben wird. Die zeitverzögerten Reaktionen sind hauptsächlich eine Folge von Lebensraumfragmentierung, mehr noch als von Lebensraumverlust. Meine Ergebnisse zeigen, dass das Vorkommen von Ameisenbären seit 1985 stark rückläufig ist, insbesondere seit 2000, als die Ausweitung von Agrarflächen besonders stark zunahm. Abschließend konnte ich zeigen, dass Pekaris meist in abgelegenen Regionen mit hohem Waldanteil vorkommen, sowie dass physiologischer Stress bei Pekaris negativ mit Nahrungsverfügbarkeit korreliert, jedoch nicht mit Abholzung. Meine Arbeit legt nahe, dass Abholzung generell zum Artensterben im argentinischen Chaco beiträgt. Während manche Arten sehr schnell verschwinden, sterben andere nicht direkt aus, was ein Zeitfenster für Naturschutzmaßnahmen eröffnet. Die hier vorgestellten Ergebnisse können dabei helfen solche Zeitfenster in von Abholzung bedrohten Gebieten zu identifizieren. / Land-use change is a primary driver of biodiversity loss. During recent decades, the tropics and subtropics have witnessed accelerating deforestation rates, resulting in widespread extinctions. Even if further deforestation was to be avoided, species would likely continue to disappear due to delays in their responses to land-use change. The goals of this thesis were to provide a better understanding of the effects of past and contemporary land use on biodiversity in the Argentine Dry Chaco, and to develop approaches that capture the impacts of land-use change on biodiversity before local extinctions occur. The Argentine Dry Chaco provides an excellent scenario for this purpose due to its dynamic land-use history, the high deforestation rates, and its high biodiversity levels. At the community level, I found that species richness of birds and mammals was influenced by past landscape patterns, suggesting time-delayed responses to land-use change and the evidence of an extinction debt. These time-delayed responses were due to habitat fragmentation rather than habitat loss. At the population level, I found that giant anteater occupancy decreased particularly after 2000 when agriculture expanded rapidly. My results further suggested that land-use change had substantial indirect effects on species’ populations. Finally, I assessed the effects of deforestation on collared peccaries at the population and individual level. Peccary occupancy was highest in areas with high woodland cover. Where peccaries were present, physiological stress was negatively correlated with food availability. Overall, this thesis shows that deforestation is driving species to extinction in the Argentine Dry Chaco. While some species may disappear quickly following deforestation, extinctions of others may not be immediate, providing an opportunity to prevent those extinctions. The approaches presented in this thesis help to identify those opportunities in dynamic landscapes such as deforestation frontiers.

No description available.

No description available.

Seed-oil based biodiesel production particularly biodiesel production from the nonedible oil seed bearing plant - Jatropha curcas L. - is a key strategic direction outlined in the biofuels strategy of the Government of Ethiopia. The main objective underlying the strategy include substitution of imported diesel oil used in the road transport sector while at the same time contributing to the local and global greenhouse gasses (GHG) reduction efforts. In this study the environmental benefits and costs of production and use of Jatropha biodiesel in the road transport sector of Ethiopia is assessed using a life cycle analysis (LCA) methodology. The analysis focused on determining the potential environmental impacts and net non-renewable energy saving potential of biodiesel from Jatropha oil-seeds using the following metrics: (i) Net Greenhouse Gas (GHG) reduction, and (ii) Net Energy Balance (NEB) relative to diesel oil. The study shows that the net GHG emissions reduction potential of Jatropha Methyl Ester (JME) is highly influenced by the magnitude of initial carbon loss occurring in the process of conversion of different land uses to Jatropha plantation, and less so on other unit processes of JME production system analysed. The NEB of JME relative to use of diesel oil per functional unit of one GJ is less sensitive to impacts of land use change and is generally positive. Where no land use change impacts is considered, or where Jatropha is grown on lands with low carbon stock such as grasslands, substitution of diesel oil with JME in Ethiopia can provide GHG emission reduction of about 43%, and for each MJ of JME produced the nonrenewable energy requirement will be 0,38 MJ. Production of JME by converting lands with high above ground, below ground and/or soil carbon stocks such as shrub lands or well stocked forest lands will result in net loss of carbon and require ecological carbon payback time of 50 to hundreds of years. The impact of introducing and use of JME-diesel oil blends by Anbassa City Bus Services Enterprise (ACBSE) bus fleets shows that, displacement of diesel oil with JME that have positive GHG reduction potential, will also contribute to the reduction of air pollutants and improvement of ambient air quality in Addis Ababa. Two key recommendations of this research work are that to ensure environmental sustainability of biodiesel production from Jatropha seeds (i) land availability and land suitability assessment for estimating the potential available land for Jatropha (and other oil-seed bearing plants) shall be conducted, and (ii) minimum requirements on GHG reduction and NEB requirements on biodiesel shall be established. / Environmental Sciences / M. Sc. (Environmental Management)

In recent years there has been an increasing awareness of the detrimental influence of diffuse sources of pollution on aquatic systems and of the integral role played by sediment in the mobilisation and transport of pollutants. The recognition of the environmental, societal and economic importance of the ecological health of aquatic environments has led to a change in emphasis regarding agricultural and environmental policy. To implement successful delivery of emerging policy requirements, there is a current need to have an enhanced understanding of the relationship between different forms of land use and sources of diffuse pollution, particularly sources of fine sediment. To understand the potential impacts of future land use changes, including environmental conservation measures on sources of sediment, it is useful to consider them within a longer-term context. This study has successfully applied the sediment source fingerprinting technique to floodplain overbank sediment cores in a retrospective study of six diverse UK river catchments with identified sediment problems. The varying estimates of relative sediment contributions from differing sources have been compared to known land use change in the study catchments over concurrent time periods, to explore any associations which might be apparent. Over the last 40 years, the increased cultivation of high erosion risk crops, such as those which are harvested late in the season (e.g. maize) and those which are sown in the autumn (e.g. winter wheat), has contributed disproportionately to the total sediment load relative to the area of land occupied by such cultivation. Increased stocking densities have resulted in increased relative sediment contributions from grassland sources, particularly intensively managed temporary grassland, but can have an even greater impact on sediment contributions derived from channel bank sources. The installation and maintenance of drainage for agriculture or for flood risk management has resulted in increased relative sediment loads from channel bank and associated sub-surface sources. Through the further development of such research, the efficacy of mitigation measures can be tested against evidence-based historic trends and those management approaches which provide identifiable improvements can be developed as best practice options for future land management targeted at reducing the negative impacts of excessive sediment ingress to river systems. The design of the source fingerprinting methodology used in this work was based on an established successful approach and this was developed further through the incorporation of a number of refinements designed to improve the robustness of the technique and expedite its implementation.

Cette thèse porte sur l’étude des impacts environnementaux de systèmes de production de bovins. Le premier objectif était d’analyser et de comparer les impacts environnementaux de systèmes de production de viande et de lait par analyse de cycle de vie (ACV) attributionnelle. Les effets de pratiques d’atténuation de ces impacts ont été évalués pour les systèmes de production de viande. Le second objectif était un développement méthodologique afin d’explorer les conséquences possibles d’une préférence accrue pour un lait produit à base d’herbe, par ACV conséquentielle. Dans un système de production de viande par le troupeau allaitant, le méthane entérique a été le principal contributeur à l’impact changement climatique, et la production de l’herbe a été la principale contributrice aux autres impacts (demande énergétique cumulée, eutrophisation, acidification, occupation du sol). L’atelier naisseur (vaches allaitantes et leurs veaux, génisses) a contribué de manière majeure aux impacts du système allaitant dans son ensemble. La pratique d’atténuation la plus efficace pour le système a été la diminution de l’âge au vêlage de 3 à 2 ans. L’utilisation de lipides riches en acides gras oméga-3 dans le régime a très peu affecté les impacts du système. L’application simultanée de plusieurs pratiques d’atténuation compatibles entre elles réduit sensiblement les impacts. L’application de pratiques telles que la réduction du gaspillage d’herbe, l’engraissement des génisses non utilisées pour le renouvellement et la diminution de l’âge au vêlage réduisent l’occupation du sol. Un usage alternatif des terres libérées tel que la plantation de forêt pour séquestrer du carbone dans la biomasse semble prometteur. L’étude de systèmes de production de lait a été centrée sur les comparaisons de systèmes à base d’herbe ou d’ensilage de maïs, d’une race spécialisée (Holstein) ou mixte (Normande) et sur l’effet du niveau de production laitière par ACV attributionnelle. Quelle que soit la méthode d’attribution des impacts aux co-produits, les impacts par kg de lait ont été plus faibles pour les systèmes à base d’ensilage de maïs et pour les Holstein, sauf pour l’eutrophisation. L’accroissement de la production de lait par vache grâce à une consommation d’énergie accrue et au vêlage à 2 ans a permis de réduire les impacts du lait et de son co-produit viande. Les conséquences de la conversion d’une exploitation laitière utilisant beaucoup de maïs ensilage vers une exploitation utilisant de l’herbe comme unique source de fourrage pour répondre à une demande de lait produit à base d’herbe en France ont été évaluées par ACV conséquentielle. Cette conversion entraîne des changements notables de l’utilisation des sols en dehors de l’exploitation, et donc un fort accroissement des impacts du système dans son ensemble et du lait produit. / This thesis addresses the environmental impacts of cattle production systems. The first objective of this thesis was to analyse and compare the environmental impacts of suckler-beef and dairy production systems using attributional life cycle assessment (ALCA). Subsequently, the effects of mitigation practices for suckler-beef production systems were assessed. The second objective addressed methodology development by exploring possible consequences due to an increase in preference for grass-based milk using consequential LCA (CLCA).For a suckler-beef production system, enteric methane fermentation was the main contributor to the climate change impact, and grassland production contributed most to other impacts (cumulative energy demand, eutrophication, acidification and land occupation). The suckler cow-calf herd substantially contributed to the impacts of the suckler-beef system. The most effective mitigation practice for the suckler-beef production system was decreasing calving age from 3 to 2 years. The use of lipids rich in omega-3 fatty acids in ruminant diets did not substantially affect the impacts of the suckler-beef production system. Simultaneous application of several compatible practices can substantially mitigate the impacts of the suckler-beef production system. The application of certain practices (e.g. reducing ungrazed grass losses, fattening heifers not used for replacement and reducing calving age) reduced land occupation. Alternative uses for the “released land”, e.g. the introduction of forest to sequester C into biomass, seems promising. For dairy production systems, the assessment focused on a grass-based vs. maize-silage-based system, dual-purpose breed (Normande) vs. specialised breed (Holstein) and the effect of increasing milk yield per cow, using the ALCA approach. Independent of co-product handling methods, the impacts per kg of milk were lower with the maize-silage-based system and with Holstein cows (except for eutrophication). Increasing milk yield per cow by increasing feed energy intake and applying more intensive management (first calving at 2 years) decreased the impacts of milk and its beef co-product. The consequences of converting a maize-silage-based to a grass-based dairy farm in France to meet the increased domestic preference for grass-based milk were assessed using the CLCA approach. This farm conversion caused land-use change outside the dairy farm and thus substantially increased the impacts of the whole production system and the milk it produced.