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Land Use, Freshwater Flows and Ecosystem Services in an Era of Global ChangeGordon, Line January 2003 (has links)
<p>The purpose of this thesis is to analyse interactions between freshwater flows, terrestrial ecosystems and human well-being. Freshwater management and policy has mainly focused on the liquid water part (surface and ground water run off) of the hydrological cycle including aquatic ecosystems. Although of great significance, this thesis shows that such a focus will not be sufficient for coping with freshwater related social-ecological vulnerability. The thesis illustrates that the terrestrial component of the hydrological cycle, reflected in vapour flows (or evapotranspiration), serves multiple functions in the human life-support system. A broader understanding of the interactions between terrestrial systems and freshwater flows is particularly important in light of present widespread land cover change in terrestrial ecosystems. </p><p>The water vapour flows from continental ecosystems were quantified at a global scale in Paper I of the thesis. It was estimated that in order to sustain the majority of global terrestrial ecosystem services on which humanity depends, an annual water vapour flow of 63 000 km3/yr is needed, including 6800 km3/yr for crop production. In comparison, the annual human withdrawal of liquid water amounts to roughly 4000 km3/yr. A potential conflict between freshwater for future food production and for terrestrial ecosystem services was identified. </p><p>Human redistribution of water vapour flows as a consequence of long-term land cover change was addressed at both continental (Australia) (Paper II) and global scales (Paper III). It was estimated that the annual vapour flow had decreased by 10% in Australia during the last 200 years. This is due to a decrease in woody vegetation for agricultural production. The reduction in vapour flows has caused severe problems with salinity of soils and rivers. The human-induced alteration of vapour flows was estimated at more than 15 times the volume of human-induced change in liquid water (Paper II). </p>
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Vetores de mudança na multifuncionalidade da paisagem costeira do Litoral Norte de São Paulo. /Pierri-Daunt, Ana Beatriz January 2019 (has links)
Orientador: Thiago Sanna Freire Silva / Resumo: As paisagens são a expressão da interação dinâmica entre processos naturais e atividades humanas. A região do Litoral Norte do Estado de São Paulo apresenta uma grande diversidade de fitofisionomias do bioma Mata Atlântica, e um rico patrimônio material e imaterial, em função da histórica interação do homem com a natureza. São inúmeros os vetores que agem simultaneamente sobre essa paisagem, resultando em efeitos cumulativos que transformam sua multifuncionalidade e multidimensionalidade. Este estudo objetivou a compreensão dos vetores de mudanças na paisagem do Litoral Norte do Estado de São Paulo. A transformação histórica da paisagem na área de estudo foi investigada buscando compreender a modificações dos cenários paisagísticos na sua integridade desde o início da colonização europeia na região de estudo. Através desta revisão histórica, demonstramos que a política econômica impulsionou investimentos em instalações tecnológicas e de acesso a região, que influenciaram no aumento das taxas de crescimento populacional, resultando num rápido crescimento das áreas urbanas após meados do século XX. O segundo capítulo quantificou as mudanças físicas da paisagem, através de séries históricas de imagens da série de satélites Landsat, utilizando o algoritmo Random Forests para classificação supervisionada do uso e cobertura da terra. Pudemos então, demonstrar que a região apresenta tendência a uma dicotomia no uso da terra, entre o uso urbano e a conservação ambiental. Entre 1985 e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Landscapes are an expression of the dynamic interaction between natural environments and human activities. The Northern Coast of São Paulo State has a high diversity of Atlantic Forest vegetation types, and the Serra do Mar mountain range has a rich material and immaterial heritage due to ancient human-nature interactions. There are several different driving forces of change acting together over these landscapes, resulting in a cumulative effect over time. Our study sought to understand the causes and consequences of landscape change in the Northern Coast of São Paulo state, from 1985 to present. We described the land use history and landscape changes since the Europeans arrived in the region, during the XVI century. We identified that national economic policies and interests have led to investment in improved access and technological development, which in turn influenced migration to the region and resulted in fast urban expansion. In the second chapter, we have shown that land use change in the Northern Coast of São Paulo poses a dichotomy between two main land cover change trajectories over 30 years: forest persistence and fast urban growth. We found only 100 km² (8%) of forest disturbance within the State Parks, while dense urban settlements grew 167% outside the park, replacing mainly rural land uses. To identify and understand the driving forces of change in the region, we used Partial Least Squares - Path Modelling to model the relation between driving forces and lands... (Complete abstract click electronic access below) / Doutor
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Modélisation des relations entre occupation - usage du sol et distribution spatiale du paludisme par télédétection optique et radar : application à un environnement en évolution : région transfrontalière Guyane Française – Brésil / Modeling the relationships between land cover, land use and malaria spatial distribution using optical and SAR remote sensing : application to a changing environment : French Guiana - Brazil cross-border areaLi, Zhichao 08 December 2016 (has links)
Le paludisme est un des maladies vectorielles les plus communes qui est situé principalement dans les régions tropicales. La zone étudiée est la région transfrontière Guyane française-Brésil. Le niveau et la dynamique intra-annuelle de la transmission y sont variables, avec un taux d’incidence qui est relativement élevé dans l’Amérique du Sud. Les facteurs environnementaux, en particulier l'occupation et l'usage du sol, influent significativement sur la présence, la densité et la distribution spatiale des moustiques du genre Anophèles, vecteurs de la maladie. Les données sur l'environnement, la population et les systèmes de santé sont rarement comparables de part et d’autre de la frontière Guyane-Brésil, excluant une vision bilatérale homogène. La télédétection permet de caractériser spatialement l’environnement de manière quasi continue et complète. L’objectif de ce travail est de caractériser par télédétection des milieux favorables au développement des vecteurs et les interactions hommes-vecteurs pour la zone transfrontalière Guyane-Brésil. Un indicateur spatialisé d’aléa de transmission du paludisme a été développé à l’échelle locale. Il permet de spatialiser la contribution de l'interaction entre milieux forestiers et non-forestiers sur la transmission du paludisme. Ce modèle a été mis en œuvre à l’échelle de la région amazonienne. Cet indice permet de quantifier et d’expliquer l’influence du paysage dans les interrelations homme - vecteurs adultes. L’identification des gîtes larvaires potentiels a été testée à une échelle régionale, à partir de la fusion d’images satellites optiques et radar, afin de mettre en évidence la distribution spatiale de zones humides pérennes et de grandes tailles (lacs, rivières, étangs, etc.) et les interfaces avec les milieux urbaines et forestiers. La distribution et la densité des vecteurs sont affectées par les propriétés physiques et chimiques des gîtes larvaires potentiels qui sont liées à la typologie des sols. Un modèle conceptuel de l’évaluation des sols adapté à la zone amazonienne présente que les caractéristiques géomorphologiques (altitude, courbure, etc.) sont indicateurs de l’évolution des sols. Une typologie des sols a été réalisée à l’échelle régionale à partir de données altimétriques et de ce modèle conceptuel. Les méthodologies, les cartes d’occupation et d’usage du sol, les cartes d’aléa du paludisme mises en place dans le cadre de cette thèse seront intégrés à l’Observatoire transfrontalier (Guyane-Brésil) qui est en cours de création. Ce travail de thèse contribue ainsi à l’exploitation des nouvelles connaissances sur le mécanisme de transmission du paludisme qui peuvent être utilisées pour définir les nouvelles stratégies de prévention aux échelles locale et régionale. / Malaria remains one of the most common vector-borne diseases what is predominantly located in the tropics. The study area is the cross-border area between French Guiana and Brazil where the level and intra-annuel dynamic of malaria transmission are variable, with the incidence rates which are relatively high in South America. The environmental risk factors, in particular, land use and land cover, significantly influence the presence, density and spatial distribution of disease vectors, Anopheles mosquitoes. Environmental information, population data and health systems database are rarely comparable on both sides of the Guyana-Brazil border which exclude the homogeneous and bilateral vision. Remote sensing permits to spatially characterize the environment on both sides of the border in an almost continuous and complete manner. The objective of this study is to characterize the favorable environment for the development of vectors and the vector-human interaction in the cross-border area between French Guiana and Brazil using remote sensing. A spatial landscape-based hazard index of malaria transmission was developed at the local scale. Such index allows spatializing the contribution of interaction between forest and non-forest areas on malaria transmission which was then implemented in the entire Amazon region. It quantifies and explains the influence of landscape on the interaction between human population and adult vectors. The identification of potential breeding sites of vectors was tested on a regional scale using the optical and SAR fusion for highlighting the spatial distribution of perennial and large wetlands (lakes, rivers, ponds etc.) and the interfaces with urban and forest environments. The distribution of vectors’ density is affected by physical and chemical properties of potential breeding sites which are related to soil typology. A conceptual model of soil evolution adapted to the Amazon region presents that geomorphological characteristics (altitude, curvature, etc.) are indicators of soil evolution. A soil classification was realized at the regional scale using altimetry data and the conceptual model. The methods, land use and land cover and malaria hazard maps established in this thesis will be integrated in the Observatory Sentinel of cross-border which is being built. This study also contributes to the exploitation of new knowledge about malaria transmission mechanism which can be used to define novel prevention strategies at the local and regional scales.
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Land Use, Freshwater Flows and Ecosystem Services in an Era of Global ChangeGordon, Line January 2003 (has links)
The purpose of this thesis is to analyse interactions between freshwater flows, terrestrial ecosystems and human well-being. Freshwater management and policy has mainly focused on the liquid water part (surface and ground water run off) of the hydrological cycle including aquatic ecosystems. Although of great significance, this thesis shows that such a focus will not be sufficient for coping with freshwater related social-ecological vulnerability. The thesis illustrates that the terrestrial component of the hydrological cycle, reflected in vapour flows (or evapotranspiration), serves multiple functions in the human life-support system. A broader understanding of the interactions between terrestrial systems and freshwater flows is particularly important in light of present widespread land cover change in terrestrial ecosystems. The water vapour flows from continental ecosystems were quantified at a global scale in Paper I of the thesis. It was estimated that in order to sustain the majority of global terrestrial ecosystem services on which humanity depends, an annual water vapour flow of 63 000 km3/yr is needed, including 6800 km3/yr for crop production. In comparison, the annual human withdrawal of liquid water amounts to roughly 4000 km3/yr. A potential conflict between freshwater for future food production and for terrestrial ecosystem services was identified. Human redistribution of water vapour flows as a consequence of long-term land cover change was addressed at both continental (Australia) (Paper II) and global scales (Paper III). It was estimated that the annual vapour flow had decreased by 10% in Australia during the last 200 years. This is due to a decrease in woody vegetation for agricultural production. The reduction in vapour flows has caused severe problems with salinity of soils and rivers. The human-induced alteration of vapour flows was estimated at more than 15 times the volume of human-induced change in liquid water (Paper II).
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Development of a flood-frequency model for the river basins of the Central Region of Malawi as a tool for engineering design and disaster preparedness in flood-prone areasLaisi, Elton 02 1900 (has links)
Since 1971, a number of flood frequency models have been developed for river basins in
Malawi for use in the design of hydraulic structures, but the varied nature of their results
have most often given a dilemma to the design engineer due to differences in magnitudes
of calculated floods for given return periods. All the known methods for flood frequency
analysis developed in country so far have not used a homogeneity test for the river basins
from which the hydrological data has been obtained. This study was thus conducted with a
view to resolving this problem and hence improve the design of hydraulic structures such
as culverts, bridges, water intake points for irrigation schemes, and flood protection dykes.
In light of the above, during the course of this study the applicability of existing methods
in the design of hydraulic structures was assessed. Also, the study investigated how land
use and land cover change influence the frequency and magnitude of floods in the study
area, and how their deleterious impacts on the socio-economic and natural environment in
the river basins could be mitigated / Environmental Sciences / M. Sc. (Environmental Management)
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Cartografia aplicada à análise ambiental de bacia hidrográfica: um estudo de caso na bacia do rio Pirapozinho / Cartography applied to the environmental analysis of watershed: a case study in the Pirapozinho watershedRODRIGUES, Bruno Magro 20 February 2017 (has links)
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Previous issue date: 2017-02-20 / The present work aimed to develop the cartographic project and production as a support to the environmental planning and analysis of the water resources` quality of the Pirapozinho watershed. To accomplish this, it was followed a script that contemplated the developmental stages of the cartographic design and production processes with the intention to subsidize the environmental analysis of watersheds. The principles of cartographic communication were applied in the design and production of thematic maps. The environmental analysis process was elaborated from the compilation of the data collected in the cartographic production stage, supported by physical-chemical and bacteriological analyzes of the surface waters of the Pirapozinho watershed. The work sought to reflect on environmental sustainability and land uses regarding to environmental quality and water resources. By means of the environmental situation identification in the studied watershed, correlations were made between the physical aspects raised and the surface water quality. The results pointed to impacts in the watershed due to the inadequate process of watershed occupation. A vegetative deficit stands out, as intense occupation of pasture and crops. Also noteworthy is the influence of industrial effluent discharges in the Pirapozinho river drainage head areas in its main course. The analysis of surface water indicated a possible points of water contamination. The parameters above the acceptable limit according to the resolution Conama 357/05, as amended by Conama Resolution 430/11, were: biochemical demand for oxygen, phosphorus, dissolved oxygen, total nitrogen and Escherichia coli. These changes are attributed to industrial and agricultural activities in the studied watershed. / O presente trabalho possuiu como objetivo desenvolver o projeto e a produção cartográfica como suporte ao planejamento ambiental e análise da qualidade dos recursos hídricos da bacia hidrográfica do rio Pirapozinho. Para isso foi seguido um roteiro que contemplou as etapas de desenvolvimento dos processos de projeto e produção cartográfica com o intuito subsidiar a análise ambiental de bacias hidrográficas. Os princípios da comunicação cartográfica foram aplicados no projeto e na produção dos mapas temáticos. O processo de análise ambiental foi elaborado a partir da compilação dos dados levantados na etapa de produção cartográfica, apoiado por análises físico-químicas e bacteriológicas das águas superficiais da bacia hidrográfica do rio Pirapozinho. O trabalho buscou trazer reflexões sobre a sustentabilidade ambiental e os usos da terra relacionados com a qualidade ambiental. Por meio da identificação da situação ambiental da bacia estudada foram realizadas relações entre os aspectos físicos levantados e a qualidade das águas superficiais. Os resultados apontam para impactos na bacia hidrográfica oriundos do inadequado processo de ocupação da bacia. Destaca-se um déficit vegetacional, e intensa ocupação de pastagem e culturas. Destaca-se também a influência do lançamento de efluente industrial em áreas da cabeceira de drenagem do rio Pirapozinho em seu curso principal. Pelas análises de águas superficiais foi possível identificar pontos de contaminação hídrica. Os parâmetros que encontraram-se acima do limite aceitável segundo a resolução Conama 357/05, alterada pela resolução Conama 430/11, foram: demanda bioquímica de oxigênio, fósforo, oxigênio dissolvido, nitrogênio total e Escherichia Coli. Atribui-se estas alterações as atividades industriais e agropecuárias na bacia estudada.
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Biogeografia da conservação frente à expansão agrícola: conflitos e prioridades / Conservation Biogeography faced with agricultural expansion: conflicts and prioritiesDOBROVOLSKI, Ricardo 10 April 2012 (has links)
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Previous issue date: 2012-04-10 / Agriculture is the human activity with the greatest impact on the environment.
Specifically, it represents the greatest threat to biodiversity. In the future, this activity
should expand due to population growth, increased consumption and production of
biofuels from food. To understand the possible impacts of this expansion on biodiversity,
we used scenarios of land use change between 1970 and 2100 from IMAGE (Integrated
Model to Access Global Environment) to test the following hypotheses: (i) areas
considered as global priorities for conservation by international NGOs will be
preferentially impacted by agricultural expansion in the XXI century, (ii) there is a conflict
between the priority areas for carnivores conservation and agricultural expansion, and this
conflict can be reduced by incorporating information on agricultural expansion in the
prioritization process, (iii) the integration among countries for conservation planning may
benefit both biodiversity and agricultural productivity, (iv) Brazilian protected areas will be
impacted by agricultural expansion in the future and this impact will differ between
protected areas of integral protection and those of sustainable use. We found that: (i) the
impact on priority areas for conservation depends on the criteria by which they were set, so
that areas defined by its high vulnerability are currently most affected than those of low
vulnerability. Throughout the XXI century this impact is expected to increase, although the
difference between the two types of priorities remains, except for High Biodiversity
Wilderness Areas, defined by their low vulnerability in current time, but for which most
pessimistic scenarios forecast an impact similar to priority areas of high vulnerability, (ii)
there is a high spatial congruence between areas with high agricultural use in the future and
priority areas for conservation of carnivores. This conflict can be reduced if the
prioritization process include information on agricultural expansion; this incorporation,
however, causes a profound change in the distribution of priority areas and reduces the
number of protected carnivore populations, (iii) the integration of countries to create a set
of priority areas for conservation that represents 17% of the land surface can protect 19%
more mammal populations without reducing food production, compared to a strategy in which each country seeks to protect its territory independently, and (iv) the impact of
agriculture in Brazil is expected to increase until the end of the century, threatening even
the protected areas and their surroundings. This impact, however, should not be different
between areas of sustainable use and those of integral protection. We conclude that
agricultural expansion should remain a major threat to biodiversity in the future, even in
areas of special interest for conservation. Conservation actions should be planned taking
into account this threat in order to reduce their potential impacts. For this, countries like
Brazil should strengthen its surveillance on agricultural expansion and on how this activity
is developed. Furthermore, the integration of international conservation efforts should be
pursued, given its benefits for biodiversity and food production. Finally, humanity must
choose methods of agricultural production that reduce its impacts, including avoiding its
future expansion, so as to meet the increasing needs of a human population globally. / A agricultura é a atividade humana com maior impacto sobre o ambiente.
Particularmente, ela representa a maior ameaça à biodiversidade. No futuro, essa atividade
deve expandir-se com o aumento populacional humano, o aumento do consumo e a
produção de biocombustíveis a partir dos alimentos. Para entender os possíveis impactos
dessa expansão sobre a biodiversidade, nós utilizamos cenários de mudança de uso do solo
entre 2000 e 2100 do IMAGE (Integrated Model to Access Global Environment) para testar as
seguintes hipóteses: (i) as áreas consideradas como prioridades globais de conservação pelas
ONGs internacionais serão preferencialmente impactadas pela expansão agrícola no século
XXI; (ii) há um conflito entre áreas prioritárias para a conservação de carnívoros e a
expansão agrícola e esse conflito pode ser reduzido com a incorporação da informação
sobre expansão agrícola no processo de priorização; (iii) a integração entre os países para o
planejamento da conservação pode ser favorável à proteção da biodiversidade e à produção
agrícola; (iv) no Brasil, as áreas protegidas serão impactadas pela expansão agrícola no
futuro e esse impacto será diferente entre áreas de proteção integral e áreas de uso
sustentável. Nós encontramos os seguintes resultados: (i) o impacto sobre as áreas
prioritárias para a conservação depende dos critérios pelos quais elas foram definidas,
assim, as áreas definidas por sua alta vulnerabilidade estão atualmente mais impactadas do
que áreas de baixa vulnerabilidade. Ao longo do século XXI, o impacto geral da agricultura
deve aumentar, mas a diferença entre os dois tipos de prioridades se mantém, exceto para
as High Biodiversity Wilderness Areas, definidas por sua baixa vulnerabilidade, mas que nos
cenários mais pessimistas podem ter um impacto agrícola semelhante ao das áreas de alta
vulnerabilidade; (ii) há uma alta congruência espacial entre áreas com elevado uso agrícola
no futuro e áreas prioritárias para a conservação de carnívoros; esse conflito pode ser
reduzido se o processo de priorização incluir as informações sobre a expansão agrícola; a
incorporação dessa informação, entretanto, provoca uma profunda alteração na
distribuição das áreas prioritárias e reduz o número de populações de carnívoros
protegidas; (iii) a integração entre os países para a criação de um conjunto de áreas
prioritárias para conservação que represente 17% da superfície terrestre pode proteger 19% mais populações de mamíferos sem reduzir a produção de alimentos, se comparada a uma
estratégia em que cada país busque proteger seu território independentemente; (iv) o
impacto da agricultura no Brasil deve aumentar até o fim do século XXI, ameaçando
inclusive as áreas protegidas e o seu entorno. Esse impacto, porém, não deve ser diferente
entre as áreas de uso sustentável e aquelas de proteção integral. Assim, a expansão agrícola
deve continuar a ser uma importante ameaça à biodiversidade no futuro, atingindo
inclusive áreas de especial interesse para a conservação. As ações de conservação devem ser
planejadas levando em consideração essa ameaça, a fim de reduzir seus impactos potenciais.
Para isso, países como o Brasil devem reforçar sua vigilância sobre a expansão agrícola e a
maneira como essa atividade é desenvolvida. Além disso, a integração internacional dos
esforços de conservação deve ser buscada, dados seus benefícios para a biodiversidade e
para a produção de alimentos. E por fim, a humanidade deve optar por formas de
produção agrícola que reduzam seus impactos, inclusive evitando sua expansão futura, mas
que possam satisfazer as necessidades da população humana globalmente.
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Quantifying landscape anthropisation patterns: concepts, methods and limits / Quantification de la structure spatiale de l'anthropisation des paysages: concepts, méthodes et limitesVranken, Isabelle 24 February 2015 (has links)
Since human beings began to use and shape the land, their influence on their<p>environment has kept on growing so that little or no ecosystem in the world is now<p>considered as untouched. This induces pressures on ecosystem health and land scarcity.<p>Africa is of particular concern because it still presents broad undisturbed zones and<p>key ecosystem services, despite being submitted to increasing anthropogenic pressures.<p>Landscape ecology appears suitable for the study of such phenomena, thanks to its spacebased<p>integrative nature and geographical level of focus. It studies the impact of spatial<p>pattern transformation — especially heterogeneity and its components — on ecological<p>processes and provides powerful analytical tools of landscape anthropisation.<p>The main objective of this thesis is to organise the concepts and methods, from<p>landscape ecology and related disciplines, into a consistent logic, to pinpoint missing<p>analytical frameworks for response-oriented anthropisation assessment, and to apply them<p>to African cases to explore the spatial patterns of anthropisation. In order to address<p>landscape anthropisation, we assemble diverse disciplines into a logical network (DPSIR).<p>The new theoretical framework is tested on Lubumbashi (DRC). In order to address<p>spatial patterns, we first evaluate the thermodynamic connection of the term entropy in<p>landscape ecology: spatial heterogeneity, unpredictability and scale influence. Then, based<p>on 20 landscapes, we highlight the complex relationship between spatial heterogeneity<p>and landscape anthropisation. We finally use the modelled relationships to test the<p>anthropogenic origin of the spatial pattern of a land cover class in Lubumbashi.<p>The main results of this research show that several concepts are used to describe different<p>aspects of anthropisation and that its quantification strongly depends on the reference states.<p>Data formats can be combined into a new assessment method ensuring more precision<p>and comparability, but a good field knowledge is required. As for heterogeneity, the<p>existing definitions of landscape entropy follow the logic of thermodynamics or information<p>theory, that are not compatible. Only unpredictability could be properly interpreted in<p>thermodynamic terms if energy transfer measurements were performed at the appropriate<p>level. The anthropogenic effects on heterogeneity completely diverge depending on the<p>amount of already anthropised surface, on the land cover type (natural or anthropogenic),<p>and on the heterogeneity components.<p>The aforementioned findings could be adapted to include functional aspects and<p>better address the relationship between spatial pattern and ecological processes. Such<p>integration would help designing response actions that can recommend human activities<p>and spatial patterns that could optimise the use of land to ensure ecological functioning<p>while supporting human development. / <p>L’influence croissante de l’homme sur son environnement affecte désormais le monde<p>entier, ce qui induit des pressions sur la santé des écosystèmes et raréfie les ressources<p>en terres. L’Afrique présente un intérêt particulier à cet égard car elle contient de vastes<p>zones quasi vierges et fournit des services écosystémiques importants mais est soumise<p>à des pressions anthropiques croissantes. L’écologie du paysage étudie ces phénomènes<p>de façon intégrative au moyen de sa composante spatiale et de son échelle d’intérêt. Elle<p>étudie l’impact des transformations de la structure spatiale — en particulier l’hétérogénéité<p>et ses différentes composantes—sur les processus écologiques et fournit de puissants outils<p>analytiques de l’anthropisation.<p>L’objectif de cette thèse est d’organiser les concepts et méthodes de différentes disciplines<p>de façon à mettre en évidence leurs forces et faiblesses pour proposer une nouvelle<p>quantification de l’anthropisation, orientée vers la gestion, et de la tester sur des paysages<p>africains pour examiner la structure spatiale de l’anthropisation. Le DPSIR est utilisé pour<p>assembler les différents concepts. La nouvelle méthodologie est testée sur Lubumbashi<p>(RDC). Ensuite, le lien entre la thermodynamique et l’utilisation du terme entropie en<p>écologie du paysage est examiné. Vingt paysages servent alors à mettre en évidence la<p>complexité de l’impact de l’anthropisation sur l’hétérogénéité du paysage. Enfin, cette<p>modélisation sert à mettre en évidence l’origine anthropique de la structure spatiale d’une<p>classe d’occupation du sol à Lubumbashi.<p>Les résultats principaux de cette recherche sont que pléthore de termes sont utilisés<p>pour représenter différents aspects de l’anthropisation et que sa quantification dépend de<p>la définition d’états de référence. Cependant, la combinaison de différents formats de<p>données peut aboutir à une nouvelle méthodologie plus précise et adaptable, mais cela<p>nécessite une bonne connaissance de terrain. Les définitions de l’entropie dépendent soit de<p>la thermodynamique soit de la théorie de l’information, qui ne sont pas compatibles. Seule<p>l’imprévisibilité pourrait être interprétée thermodynamiquement, si les mesures de transfert<p>d’énergie étaient effectuées à l’échelle appropriée. L’impact humain sur l’hétérogénéité<p>diverge selon la quantité de surface déjà anthropisée, le type de couverture du sol pris en<p>compte ainsi que les composantes de l’hétérogénéité mesurées.<p>Ces découvertes peuvent être adaptées pour intégrer des aspects fonctionnels de la<p>structure spatiale et mieux cerner le lien entre celle-ci et le fonctionnement écologique, ce qui<p>permettrait de proposer des activités humaines et des structures spatiales qui optimiseraient<p>l’utilisation des ressources en sol pour assurer tant le fonctionnement écologique que le<p>développement humain. / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished
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Hodnocení ekosystémových služeb a alternativ jejich dalšího vývoje v biosférických rezervacích UNESCO / Assessing ecosystem services and the alternatives of their future development in UNESCO Biosphere ReservesHarmáčková, Veronika Zuzana January 2016 (has links)
The provision of ecosystem services within social-ecological systems is influenced by multiple environmental and anthropogenic driving forces, affecting natural ecosystems. At the same time, the capacity of ecosystems to concurrently provide different types of ecosystem services is inherently limited. Thus, ecosystem changes and their effect on ecosystem services have direct implications for human existence and well-being. The aim of this thesis is to present a modelling approach to assess regulating, provisioning and cultural ecosystem services and to quantify their potential trade-offs, illustrated by two case studies carried out in selected UNESCO Biosphere Reserves in the Czech Republic, Třeboň Basin Biosphere Reserve and Šumava Biosphere Reserve. Both of the selected case study areas are characterized by high levels of natural and cultural assets and challenges regarding future landscape management. In this study, first the social-ecological dynamics within the study areas was analysed by creating participative scenarios through collaboration with local stakeholders, eliciting their preferences regarding future landscape development to 2050. Second, the impact of the scenarios on ecosystem services and their trade-offs were assessed using a combination of spatially explicit models and...
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Hodnocení ekosystémových služeb a alternativ jejich dalšího vývoje v biosférických rezervacích UNESCO / Assessing ecosystem services and the alternatives of their future development in UNESCO Biosphere ReservesHarmáčková, Veronika Zuzana January 2016 (has links)
The provision of ecosystem services within social-ecological systems is influenced by multiple environmental and anthropogenic driving forces, affecting natural ecosystems. At the same time, the capacity of ecosystems to concurrently provide different types of ecosystem services is inherently limited. Thus, ecosystem changes and their effect on ecosystem services have direct implications for human existence and well-being. The aim of this thesis is to present a modelling approach to assess regulating, provisioning and cultural ecosystem services and to quantify their potential trade-offs, illustrated by two case studies carried out in selected UNESCO Biosphere Reserves in the Czech Republic, Třeboň Basin Biosphere Reserve and Šumava Biosphere Reserve. Both of the selected case study areas are characterized by high levels of natural and cultural assets and challenges regarding future landscape management. In this study, first the social-ecological dynamics within the study areas was analysed by creating participative scenarios through collaboration with local stakeholders, eliciting their preferences regarding future landscape development to 2050. Second, the impact of the scenarios on ecosystem services and their trade-offs were assessed using a combination of spatially explicit models and...
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