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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
441

Vers une prise en compte des potentialités des sols dans la planification territoriale et l’urbanisme opérationnel / Towards taking into account the potential of soils in urban planning

Blanchart, Anne 14 November 2018 (has links)
Le développement des aires urbaines induit une amplification des enjeux environnementaux (e.g. qualité de l’air, îlot de chaleur urbain, inondation). Pour apporter une réponse à ces défis, la fabrique urbaine intègre progressivement les fonctions assurées par les écosystèmes urbains. Cependant, cette considération semble négliger les services écosystémiques rendus par la composante « sol » des aires urbaines. À ce titre, l’objectif du doctorat est d’appréhender les apports d’une prise en compte avancée des potentialités des sols urbains dans la planification territoriale et l’urbanisme opérationnel. Une enquête nationale auprès d’acteurs de la planification territoriale et des entretiens individuels avec des professionnels de l’urbanisme opérationnel ont été menés. Il en ressort que ces acteurs ont commencé à développer une considération systémique des sols urbains, dépassant leur vision initiale du sol comme simple surface foncière. Afin de formaliser la manière de prendre en compte les potentialités des sols urbains, des campagnes d’échantillonnage de sols ont été réalisées sur 10 sites de projets localisés au sein de trois aires urbaines aux contextes pédoclimatiques différents (Métropole du Grand Nancy, Métropole d’Aix-Marseille Provence, Nantes Métropole). Une description de profils de sols et leur caractérisation physico-chimique ont permis d’appréhender leur état et de mener une étude comparative de leur qualité. Il s’avère que près de la moitié des sols urbains étudiés n’étaient pas des sols fortement anthropisés (e.g. Anthrosols, Technosols) et étaient analogues à des sols agricoles voisins. Ils présentaient une très grande hétérogénéité de leurs propriétés, rendant complexe leur appréhension par les acteurs de la fabrique urbaine. Les données pédologiques ont alors été intégrées dans un outil d’aide à la décision, afin de les traduire en capacité des sols à assurer des fonctions et rendre des services écosystémiques. Il s’est avéré que les sols fortement anthropisés pouvaient présenter des niveaux de services écosystémiques équivalents, voire supérieurs, à ceux fournis par certains sols agricoles, pouvant répondre aux enjeux environnementaux, sociaux voire économiques des aires urbaines. L’intégration de ces informations lors de différentes étapes de mise en œuvre d’un projet urbain peut contribuer à améliorer la durabilité des aires urbaines, en optimisant l’usage des sols urbains et en préservant les plus multifonctionnels d’entre eux / Urban areas, in addition to global environmental issues, concentrate major local environmental concerns such as air quality, urban heat island and flood mitigation. To tackle those issues, every land surface should be considered as a potential supplier of ecosystem services. However, the urban soils contribution remains poorly assessed up to now. As a result, there is a strong lack of consideration by urban planning of the services that urban soils could provide. So, the main goal of this PhD is to propose a methodology that facilitates an advanced integration of urban soils potentials in urban planning. A national survey and some individual interviews with actors of urban planning were conducted. These actors have progressively developed a systemic consideration of urban soils, and do not yet consider them only as land surfaces. Then, soil sampling campaigns were carried out on 10 urban projects, located in three urban areas with contrasted pedoclimatic contexts (Métropole du Grand Nancy, Métropole Aix-Marseille Provence, Nantes Métropole). The description of the pedological pits and the physico-chemical characterization of soil samples led us to conduct a comparative study of their quality. It appears that 49% of the studied soils were not highly anthropized soils (e.g. Anthrosols, Technosols) and presented bio-physico-chemical properties which were similar to surrounding agricultural soils. The results also showed that the highly anthropized soils presented a high variation of their properties. The results of the physico-chemical characterization had been feed into a decision support tool. This DSS could evaluate the capacity of an urban soil to provide some fonctions and ecosystem services. It appears that the highly anthropized soils were able to provide levels of ecosystem services that were equivalent to, or even higher, than those provided by agricultural soils. In result, it has been demonstrated that urban soils could provide some ecosystem services in order to answer to environmental, social and economic challenges. So, the consideration of the potential of soils in an urban project could contribute to improve sustainability of cities, by optimizing the uses of urban soils and preserving the most multifunctional
442

Composição e configuração da cobertura florestal na bacia hidrográfica e seus efeitos nos serviços hidrológicos / Effects of forest cover composition and spatial configuration in hydrological services at catchment scale

Lara Gabrielle Garcia 09 October 2018 (has links)
Programas de restauração florestal e pagamento por serviços ecossistêmicos vêm sendo incentivados em várias regiões que apresentam problemas de abastecimento hídrico, com objetivo de recuperação e manutenção dos recursos hídricos. Embora se considere que a cobertura florestal é benéfica para a conservação dos recursos hídricos, esta relação é complexa e dependente de vários fatores físicos, assim como da proporção e da configuração espacial da cobertura florestal na bacia hidrográfica. Diante deste contexto, o objetivo geral do presente estudo foi avaliar os efeitos da proporção e configuração espacial da cobertura florestal na bacia hidrográfica no aumento ou manutenção dos serviços hidrológicos. Para tal, um modelo hidrológico distribuído de base física foi calibrado e validado para permitir a simulação hidrológica dos diferentes usos da terra. A parametrização do modelo teve como base uma bacia hidrográfica monitorada (deflúvio e precipitação) de características agrícolas (pastagem e cana-de-açúcar). Após calibrado e validado o modelo (R2 de 0,65 e 0,62 respectivamente), os cenários a serem simulados foram gerados modificando-se a composição da paisagem (proporção de cobertura florestal) e a configuração espacial da cobertura florestal. É importante ressaltar que as modificações no modelo para cada uso foram referentes diretamente aos processos de evapotranspiração e escoamento superficial e seus desdobramentos. Não foram modificados os processos referentes ao solo (e.g. infiltração e percolação), uma vez que a influência do uso na estrutura do solo ainda é um ponto conflitante. Os serviços hidrológicos considerados foram os de disponibilidade hídrica e proteção. Os indicadores para análise da disponibilidade hídrica foram o deflúvio anual (Q), vazões mínimas (Q95) e índice de fluxo base (BFI); e os indicadores de proteção foram as vazões máximas (Q5) e índice de velocidade (IF). O efeito da proporção da cobertura florestal foi testado por meio de cenários com aumento aleatório de 10% na cobertura florestal (CF), iniciando com o cenário referência de 0% CF até o cenário referência de 100% (11 cenários simulados). As hipóteses testadas foram de que (i) o aumento da cobertura florestal diminui o serviço hidrológico de disponibilidade hídrica, e (ii) o aumento da cobertura florestal aumenta o serviço hidrológico de proteção. Ambas as hipóteses foram aceitas, uma vez que, apesar de os resultados terem apresentado diferenças relativas entre os cenários, não foi possível obter diferença estatística para todos os indicadores. Foi constatada diminuição dos indicadores de Q e Q95 e aumento nos valores de Q5 seguidos de aumento da cobertura florestal. A diferença estatística ocorreu para os indicadores Q e Q5, sendo que em ambos foi possível perceber um limiar de 50% CF, a partir do qual o deflúvio anual e o índice de máximas passaram a ser estatisticamente diferentes do cenário 0% CF. O efeito da configuração espacial foi testado por meio de simulações de cenários com a mesma proporção de cobertura florestal, mas com alterações quanto a sua configuração espacial. Foram simulados quatro cenários: CF no terço inferior (INF); CF no terço médio (MED); CF no terço superior (SUP) da bacia hidrográfica; e CF aleatoriamente distribuída na área (ALE). As hipóteses testadas foram que (i) a configuração espacial da cobertura florestal na bacia hidrográfica não tem influência no serviço hidrológico de disponibilidade de água; e (ii) a configuração espacial da cobertura florestal nas áreas próximas aos corpos hídricos (terço inferior) tem influência positiva no serviço de proteção, ou seja, no aumento deste serviço. Os resultados permitiram aceitar parcialmente as hipóteses, uma vez que apesar de relativamente ocorrer diferenças no serviço hidrológico de disponibilidade hídrica esta não foi estatisticamente significativa, o mesmo ocorrendo para o serviço de proteção. Assim como anteriormente, os resultados permitiram perceber um trade-off entre os serviços testados, pois o cenário com maior redução nos valores de Q e Q95 (INF) foi o que apresentou as maiores reduções no índice de vazão máxima. No entanto, mesmo com a diminuição nos indicadores de disponibilidade hídrica, o cenário com cobertura florestal na parte inferior da bacia hidrográfica foi considerado o mais próximo a um ótimo em relação aos serviços hidrológicos. Diante dos resultados encontrados, pode-se observar que ao se tratar de serviços hidrológicos a cobertura florestal pode apresentar trade-off entre os mesmos, sendo necessário aos programas de restauração e pagamento de serviços ambientais conhecerem esta dinâmica para maximizarem o serviço hidrológico de interesse. / Water resources recovery and maintenance are the main objectives of restoration cover forest programs and payment for ecosystem services. These programs are gaining force and incentives, especially in water crises regions. However, water resources recovery and maintenance are attributed in many cases to forest cover effects on hydrological processes and, consequently, on hydrological services. In this context, our aim in this study was to evaluate if forest cover restoration can result in increase or maintenance of hydrological services. Therefore, firstly it was necessary to calibrate and validate a distributed hydrological physical base model to simulate different land use at the catchment scale. The model parameterization was done on a monitored catchment (flow and precipitation) of agricultural characteristics (pasture and sugar cane). After calibrating and validating the model (R2 of 0.65 and 0.62, respectively), the land use scenarios were generated based on two landscape approaches: forest cover proportion and spatial configuration on catchment scale. The hydrological services used were water supply and protection; indicators for analysis were annual flow (Q), minimum flows (Q95), base flow index (BFI); maximum flows (Q5) and velocity index (IF). Q, Q95 e BFI correspond to water supply, the others are flood protection service. The first approach objective was tested forest cover proportion scenarios with a random increase in forest cover (CF) of 10%, starting with 0% CF reference scenario to 100% CF reference scenario (total of 11 simulated scenarios). The hypotheses tested were that (i) the random increase in forest cover decreases the hydrological service of water supply, and (ii) the random increase in forest cover increases the hydrological protection service. Both hypotheses were partially accepted. Since the results showed relative differences between the scenarios without statistical difference. There was a decrease in Q and Q95 indicators and an increase in Q5 values followed by an increase in forest cover. The statistical difference happened only for Q and Q5 indicators. For both hydrological services it is possible to perceive a threshold of 50% CF, from which the flow annual and the maximum index become statistically different from the 0% CF scenario. The second approach was the simulations of same forest cover proportion scenarios, however with changes in their spatial configuration. Four scenarios were simulated: CF in the lower land (LOW); CF in the middle land (MIDD); CF in the upper lands (UPP) of the river basin; and CF randomly distributed in the area (RAN). The hypotheses tested were (i) the forest cover spatial configuration has no influence on water supply hydrological service; and (ii) the forest cover spatial configuration in areas near the water bodies (lower land) has a positive impact on protection hydrological service. Our results allowed partially accepting the hypotheses, since there are relative differences in the water supply hydrological service after scenarios simulation, there was no statistically significant difference, the same occurring for the protection hydrological service. The results allow us to highlight a trade-off between hydrological services tested in this study, for example, the scenario with the greatest reduction in Q and Q95 values (LOW) also presented the greatest reductions in Q5. However, even with the decrease in water supply indicators, the LOW scenario was considered the closest to an optimum scenario to hydrological services. In view of this, we can be observed that forest cover can present hydrological services trade-off, being necessary to restoration and payment of environmental services programs to know dynamics to maximize the hydrological service of interest. It is important to emphasize that these results and analyses simulations were based on land use change scenarios (related to the evapotranspiration and surface runoff processes) and their unfolding, however, were not modified (e.g. infiltration and percolation). However, land use effects on the soil structure are still not proved a point, possibly these being key processes to forest cover restoration and hydrological services trade-off.
443

A função do direito na fase da reconstrução identificada pela gestão circular dos desastres climáticos

Scherer, Kátia Ragnini 30 March 2017 (has links)
Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-08-03T14:13:25Z No. of bitstreams: 1 Kátia Ragnini Scherer_.pdf: 4709462 bytes, checksum: c2712b965209d1f13cca1045e1043cfa (MD5) / Made available in DSpace on 2017-08-03T14:13:25Z (GMT). No. of bitstreams: 1 Kátia Ragnini Scherer_.pdf: 4709462 bytes, checksum: c2712b965209d1f13cca1045e1043cfa (MD5) Previous issue date: 2017-03-30 / Nenhuma / A tese tem como tema a função do Direito na reconstrução identificada pela gestão circular dos desastres climáticos. A delimitação centra-se na função do Direito no estágio da reconstrução pós-desastre. O problema proposto consiste em saber: sob quais condições a policontexturalidade dos SE instrumentaliza a função do Direito na reconstrução identificada pela gestão circular dos desastres climáticos? O objetivo geral é analisar reflexivamente as possibilidades de observação do Direito em relação à policontexturalidade dos SE e a gestão circular do Direito para a reconstrução resiliente no pós-desastre. A estrutura do trabalho está construída de modo que cada capítulo acompanhe cada objetivo específico, sendo estes: a) examinar como o Direito observa os riscos climáticos para estabelecer os fundamentos da gestão pelo Direito; b) abordar a gestão cíclica dos desastres climáticos e sua assimilação pelo contexto jurídico nacional e; c) analisar reflexivamente a instrumentalidade policontextural dos SE e sua aderência ao estágio da reconstrução, por meio da diferenciação funcional para prevenção das catástrofes climáticas. O método de abordagem é o sistêmico funcional, o de procedimento é o monográfico e a técnica de pesquisa é a bibliográfica. A pesquisa confirma a hipótese no sentido de que na reconstrução resiliente os serviços ecossistêmicos devem ser assimilados pelo Direito a partir de elementos oriundos de múltiplos contextos com o da Ciência, da Política e da Economia. Tal assimilação, por sua vez, deve operar de forma recíproca pelas organizações nos processos de avaliação, monitoramento e estruturação das decisões jurídicas de curto e de longo prazos, considerando que o contexto jurídico nacional inclui a prevenção como força motriz no tratamento dos desastres pela abordagem sistêmica de ações (prevenção, mitigação, preparação, resposta e recuperação) e pela integratividade de políticas públicas. Assim é possível uma evolução para assimilação da infraestrutura natural oferecida pelos serviços ecossistêmicos com a diferenciação funcional para a prevenção e a precaução no enfrentamento aos desastres climáticos. / The thesis takes the theme of the function of Right in the reconstruction identified by the circular gestion of climatic disasters. Its limits center on the function of Law at the time of reconstruction post-disaster. The proposed problem consists in knowing: under what conditions are Ecosystem Services polycontexturality instrument for circular management of climatic disasters through Right, separated from the reconstruction stage? The general goal is to analyze reflexively the observation possibilities of Law in relation of the polycontexturality of ecosystem services and the circular management of Law for resilient reconstruction after the disaster. The structure of work is built so that every chapter follows his specific goals, which are: a) to examine how Law studies climatic risks to establish the fundamentals of Law management; b) approach the cyclic management of climatic disasters and their assimilation by the national legal context and; c) analyze reflexively the polycontexturality instrumentality of the ES and its adherence to the stage of reconstruction through the functional changes to prevent climatic disasters. The approach method is the systemic functional one, the proceeding is the monographic one and the research is bibliographic. The research confirms the hypothesis in the sense that in a resilient reconstitution, ecosystem services must be assimilated by Law, starting from elements coming from multiple contexts with Science of Politics and Economy. Such assimilation must operate reciprocally by the organizations through processes of evaluation, monitoring and structuring of legal decisions in the long and short terms, considering the national legal context and including prevention as the driving force in the treatment of disasters through systemic actions of approach (prevention, mitigation, preparation, response and recovery) and through the integration of public policies. This way, an evolution is possible to assimilate the natural infraestracture offered by ecossistemic services with function diferences for prevention and the precaution in face of climatic disasters.
444

Small-scalle fisheries of frugovorous fish in clear and black water rivers of the brazilian amazon

Nagl, Paula January 2017 (has links)
Nas florestas sazonalmente inundadas de terras baixas da Amazônia, os peixes frugívoros desempenham diferentes serviços ecossistêmicos: possuem um papel importante na dispersão de sementes (regulação), além de serem um recurso (provisão) para pescadores artesanais. O uso extensivo de recursos limitados pode gerar conflitos de interesse entre os objetivos conservacionistas e as necessidades dos habitantes locais. O co-manejo tenta integrar a segurança alimentar e a conservação dos ecossistemas na forma de reservas extrativistas (RESEX), onde os habitantes locais podem retirar recursos florestais seguindo regras de manejo. Neste trabalho testamos a influência do co-manejo sobre os peixes frugívoros do rio Tapajós (águas claras) e Negro (águas pretas) na Amazônia brasileira. Foram testadas as seguintes hipóteses: 1)Peixes frugívoros são importantes para os pescadores e são seletivamente escolhidos pela pesca; 2) A abundância, tamanho e a produtividade pesqueira dos peixes frugívoros são maior dentro da RESEX. Durante quatro meses, pescadores locais registraram 1.457 desembarques pesqueiros em oito comunidades em cada rio. Além disso, foram amostrados 12.730 peixes em 208 pontos de malhadeira em 32 sitios em lagos e no canal do rio nas comunidades estudadas. Peixes frugívoros estão entre as dez espécies mais pescadas nos dois rios, indicando a sua importância para as comunidades locais. Nos dois rios a porcentagem de peixes frugívoros era maior no registro dos desembarques pesqueiros (22% de 7.342 kg no rio Tapajós e 14% of 4.609 kg no rio Negro) que vii nas amostragens científicas (5,9% de 349,2 kg no rio Tapajós e 6% of 458,3 kg no rio Negro), indicando uma seletividade dos pescadores para os frugívoros. / In seasonally flooded forests of lowland Amazonia, frugivorous fish provide different ecosystem services (ESS): They play an important role in seed dispersal (regulating ESS), but they are also an essential resource for artisanal fisheries (provisioning ESS). Extensive use of limited resources can generate conflicts of interest between conservation goals and the needs of local livelihoods. Co-management schemes try to integrate local food security and ecosystem conservation in the form of extractive reserves (RESEX), where inhabitants are exclusively allowed to extract forest resources while following management rules. Here, we assess the influence of co-management on frugivorous fish and local fisheries of Tapajos (clear water) and Negro (black water) River in the Brazilian Amazon. To this end, we test the following hypotheses: 1) Frugivorous fish are important for fisheries and selectively extracted; 2) Frugivorous fish abundance, size and fisheries productivity is higher inside the RESEX than outside. Fish landings from 1457 fishing trips were registered over four months by local fishermen in eight fishing communities of each river. Further, 12,730 fish were sampled through 208 gillnet placements, in 32 sites in the floodplain lakes and river channels of the communities. Frugivorous fish are among the ten most fished species in both rivers, reflecting their importance for local communities. In both rivers, landing records show a higher percentage of frugivorous fish biomass (22% of 7,342 kg in Tapajós and 14% of 4,609 kg in Negro River) than samplings (5.9% of 349.2 kg in Tapajós and 6% of 458.3 kg in Negro River), indicating a selectivity of fisheries towards frugivores. A pressão pesqueira (medida como demanda por pescado) nos frugívoros se mostrou mais elevada fora de cada RESEX (8 ± 5,4 kg no Rio Tapajós e 5,6 ± 3,1 kg no Rio Negro) que dentro (0,7 ± 0,3 kg no Rio Tapajós e 0,8 ± 0,1 kg no rio Negro). A produtividade da pesca, medida em Captura por Unidade de Esforço (CPUE), e a proporção de peixes frugívoros na captura total foram maiores fora da RESEX no rio Tapajós (CPUE: t=-3,7; dF = 4,2; p = 0,02; proporçao: t = -6,7; dF = 5; p = 0,001) e não variaram no rio Negro (CPUE: t = -1,9; dF = 5,6; p = 0,1; proporçao: t = -0,9; dF = 4,6; p = 0,4). No geral, o tamanho dos peixes frugívoros foi maior dentro da RESEX no rio Negro, mas não no rio Tapajós. Os pescadores capturaram pacus de maior tamanho (Myleus spp., Mylossoma spp., Myloplus spp., Metynnis spp.) dentro da RESEX no rio Negro (D=0,42; p<0,001). No rio Tapajós não foi possível detectar efeitos da RESEX nos parâmetros medidos para os peixes frugívoros. A reserva do rio Negro parece favorecer o tamanho e a disponibilidade de peixes frugívoros, apesar de eles serem selecionados pela pesca local. Apesar de uma pressão pesqueira possivelmente elevada, peixes frugívoros foram abundantes dentro e fora da RESEX em ambos os rios, possivelmente devido a demandas do mercado, efeitos de spillover ou baixa conformidade às regras de de manejo dentro da RESEX. Contudo, os frugívoros parecem estar cumprindo seu papel de recurso alimentar e de dispersores de sementes. Nosso estudo evidencia que o monitoramento participativo baseado na comunidade é uma ferramenta economicamente eficiente para a caracterização da pesca local. No entanto, para se atingir os objetivos de conservação e assegurar o recurso alimentar, é necessário que haja um controle do acesso de pessoas de fora das áreas de conservação e um reforço do cumprimento das regras de manejo. Portanto, continua sendo possível manter os dois serviços ecossistêmicos fornecidos por esses peixes nos rios de águas claras e negras estudadas na Amazônia brasileira.
445

The ecological and economic analysis of beach management strategies in Scotland

Griffin, Caroline January 2016 (has links)
Coastlines are particularly susceptible to the necessary trade-offs which occur between different ecosystem services. Should the areas be managed for biodiversity or for people? Where sandy beaches are found there is usually a management decision to be made between managing for recreation or for biodiversity. Many popular tourist beaches (particularly those with a Beach Award) are often groomed with mechanical equipment to remove any stranded seaweed and associated litter which can get entangled in the wrack. This is likely to be having a negative impact on coastal biodiversity, with wide ranging implications for the entire habitat, including the intertidal zone, sand dunes and shorebirds. Beached wrack should be allowed to naturally decompose providing a habitat for numerous species of macro-invertebrates. These macro-invertebrate communities not only include many endemic species found exclusively along the strandline but they also provide a very rich source of food for shorebirds. The re-mineralised nutrients resulting from the decomposed macrophytes should then become available to provide a rich source of nutrients to dune, strandline and marine ecosystems populations of the strandline. In previous studies grooming has been shown to have a negative impact on the invertebrates of the strandline and this study reveals that tidal range has an effect on the impacts of grooming with a higher tidal range having a more negative impact on the invertebrates. A study to observe the impacts of grooming on both adult plant and seed bank communities of the sand dunes found that grooming is having a negative impact on these populations. Grooming is predominantly driven by beach managers who aspire to gain Beach Awards in order to attract tourists to their beaches. Using non-market valuation in the form of a stated preference choice experiment and a travel cost model, it was observed that Beach Awards are not valued by beach goers but are instead influenced to visit a particular beach by good bathing water quality, high levels of biodiversity and low levels of litter. It was also shown that stranded seaweed on the beach does not deter visitors. Future management suggestions include attempting to reduce the confusion arising from the presence of multiple beach awards by either removing them altogether or by making their criteria more clear and direct with consistency in their design and designation. Bathing water quality should be completely removed from the Beach Award system and real-time information in the form of electronic signage and a publicly available App should replace it.
446

Patrons d'organisation des traits aériens et racinaires en prairies humides : liens avec la production primaire (quantité et qualité). / Root and shoot trait patterns in wet grasslands : effects on fodder provision.

Chanteloup, Pierre 16 January 2013 (has links)
Les prairies semi-naturelles constituent des espaces multifonctionnels susceptibles de rendre de nombreux services à la société. Ce sont en particulier des agro-écosystèmes favorables à l’expression d’une grande diversité floristique et faunistique permettant de concilier enjeux écologiques et agronomiques. Ce travail de thèse vise à analyser (i) l'influence des facteurs environnementaux sur l'assemblage des communautés in situ et (ii) les relations entre la structure fonctionnelle des assemblages (i.e. valeurs de traits agrégées et diversité fonctionnelle) et leurs performances (i.e. production de biomasse et digestibilité de cette biomasse). Cette étude s'appuie sur des approches expérimentales et de terrain dans les prairies humides pâturées du Marais Poitevin. Nos résultats montrent des réponses très différentes des traits aériens et racinaires étudiés aux gradients de stress et de perturbation rencontrés dans ces prairies. Ils ont également permis de mettre en évidence l'influence prépondérante des valeurs de traits agrégées sur la fourniture de services écosystémiques (i.e. productivité et digestibilité du fourrage), en accord avec la "Biomass ratio hypothesis" énoncée par Grime. L'influence du niveau de diversité fonctionnelle sur les services rendus par les assemblages varie selon le service considéré. Contrairement aux résultats attendus selon la "Diversity hypothesis" énoncée par Tilman, le niveau de diversité fonctionnelle est lié négativement à la productivité des assemblages. En revanche, un effet positif de la diversité fonctionnelle sur la digestibilité a été mis en évidence. Cette étude a par ailleurs permis de montrer un compromis entre la productivité des assemblages et la digestibilité de la biomasse produite dans ces prairies humides. Ce travail suggère que des outils de diagnostics de la valeur fourragère du couvert peuvent être construits sur la base de la structure fonctionnelle des assemblages, et ce avec un haut niveau de fiabilité. Il met également en avant les bénéfices agronomiques associés à l'hétérogénéité des couverts végétaux rencontrés dans ces prairies. / Semi-natural grasslands form multifunctional areas susceptible to serve the society from many aspects. Indeed, they are agro-ecosystems that promote expression of a large floristic and faunistic diversity, which allows conciliating ecologic and agronomic issues. This PhD work aims at analysing (i) influence of environmental factors on natural communities' assembly rules and (ii) the relationships between the functional structure of assemblages (i.e. community weighted mean trait values and functional diversity) and their performances (i.e. biomass production and its digestibility). This study is based on both experimental and field approaches in the Marais Poitevin wet grasslands. Our results show that the studied aerial and root traits display a wide diversity of answers to stress gradients and disturbances encountered in these grasslands. Our results also highlighted the crucial influence of community weighted mean trait values on provision of ecosystem services (i.e. forage productivity and digestibility), in agreement with the Biomass ratio hypothesis set out by Grime. The influence of the functional diversity level on services provided by the assemblages differs depending on the service considered. Contrary to the results expected according to the Diversity hypothesis of Tilman, the functional diversity level is negatively correlated with the productivity of the assemblages. However, our study points to a positive feedback between functional diversity and digestibility. Furthermore, this study demonstrated the existence of trade-off between the productivity of assemblages and the digestibility of biomass produced in these wet grasslands. This work suggests that highly reliable tools can be established, based on the functional structure of assemblages, to evaluate the feeding value of a vegetal cover. This work finally illustrates the agronomic benefits associated with heterogeneous vegetal covers encountered in these grasslands.
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Serviços ecossistêmicos e a atividade minerária: um estudo de caso no Vale do Ribeira, SP / Ecosystem services and mining activities: a case study in Vale do Ribeira, SP

Mariana Hortelani Carneseca Longo 16 June 2014 (has links)
As atividades antrópicas vêm continuamente influenciando as transformações no ordenamento do solo. A mineração, em suas fases de operação e desativação, é um dos maiores agentes de mudança do uso do solo e alteração da paisagem, o que, consequentemente, resulta em modificações na dinâmica das funções ecológicas, interferindo na oferta de serviços ecossistêmicos. Considerando a inclusão da abordagem dos serviços ecossistêmicos na avaliação ambiental de empreendimentos, a partir de um estudo de caso em uma mineração de rocha fosfática (apatita), localizada no município de Cajati - SP, o presente estudo teve como objetivo responder a seguinte questão: a atividade de mineração interfere na oferta local de serviços ecossistêmicos? Para isso, o método de análise utilizado foi fundamentado em um modelo de avaliação não monetária, com base nos padrões da atividade de mineração ao longo do tempo e do espaço, bem como na capacidade das diferentes classes de uso e ocupação do solo dessa atividade em fornecer serviços ecossistêmicos. O estudo concluiu que todos os serviços ecossistêmicos avaliados são afetados pelos impactos ambientais gerados pela atividade minerária, sendo que a alteração na extensão da área ocupada por floresta nativa - tanto redução quanto aumento - é o que mais influenciou no fornecimento de serviços ecossistêmicos potenciais. Além disso, a atividade minerária ao alterar o padrão de uso e ocupação do solo e, consequentemente, alterar as funções ecológicas locais, reduziu progressivamente a oferta de múltiplos serviços ecossistêmicos e, por outro lado, a recuperação das áreas degradadas pela atividade minerária, recobrindo o solo com espécies de gramíneas e promovendo o plantio de espécies arbóreas nativas, resultou no aumento da oferta local dos serviços ecossistêmicos potenciais. A partir destes resultados fica evidente a importância das ações de recuperação de áreas degradadas pela atividade minerária para o aumento da oferta de serviços ecossistêmicos. Dessa forma, recomendou-se inserir a análise de serviços ecossistêmicos na avaliação de impactos ambientais de empreendimentos minerários, visto que a ferramenta de avaliação baseada em serviços ecossistêmicos permite identificar conflitos e sinergias entre as atividades antrópicas e os ecossistemas, fornecendo subsídios para identificar medidas adicionais de mitigação de impactos e de compensação ambiental. / Human activities have continuously influenced changes in land management. Mining in its operational and decommissioning stages, is one of the biggest agents of change in the landscape and land use, which consequently results in changes in the dynamics of the ecological functions, interfering with the supply of ecosystem services. Taking into account the ecosystem services approach in environmental project assessments and based on a case study of a rock phosphate mining operation, located in the town of Cajati - SP, this study aimed to answer the following question: does the mining activity interfere in the local supply of ecosystem services? As such, the method of analysis was based on a framework of non-monetary assessment itself based on the established patterns of the mining activity over time and space, as well as the ability of different land uses to provide ecosystem services. The result of the study was that all the analyzed ecosystem services are affected by the environmental impacts of the mining activity, and that change in the extension of the native forest (as decrease as increase) is what most affects the potential supply of ecosystem services. Moreover, as the mining activity alters the pattern of land use and occupation and consequently alters the local ecological functions, it progressively reduces the provision of multiple ecosystem services. On the other hand, the recovery of degraded areas by mining activities, covering the soil with grass species and promoting the planting of native species, allowed for the growth of the local supply of potential ecosystem services. From these results, the importance of area recovery actions is evident in increasing the supply of ecosystem services. Thus, the inclusion of the analysis of ecosystem services in the environmental impact assessment of projects is recomended, as the assessment tool based on ecosystem services allows us to identify synergies and conflicts between human activities and ecosystems, providing input to identify additional actions for impact mitigation and environmental compensation.
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Servi?os ambientais em microbacias antropizadas / Environmental services in anthropized micro-basins

Bueno, Mateus Marques 10 February 2017 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-09-20T11:28:58Z No. of bitstreams: 1 2017 - Mateus Marques Bueno.pdf: 6490424 bytes, checksum: f696a97cede78e62f97260ed46c9a661 (MD5) / Made available in DSpace on 2017-09-20T11:28:58Z (GMT). No. of bitstreams: 1 2017 - Mateus Marques Bueno.pdf: 6490424 bytes, checksum: f696a97cede78e62f97260ed46c9a661 (MD5) Previous issue date: 2017-02-10 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / In the marine fluvial plains, present along the Brazilian coast, there are intrinsic interaction between the agents coordinated by sea actions and fluvial dynamics. These interactions offer quantity and quality of environmental services to their river basins. This study characterized the Basin of the Guandu System (BHSG) and its flat land in relation to the offer of ecosystem services. Subsequently, it prospected on the factors that determine the supply and management of services as environmental assets in microbasins, strongly anthropized by mineral activity. Geoprocessing information was used to spatialize areas with similar ecosystem services and a local monitoring system to evaluate and size environmental services. The BHSG is home to Sepetiba marine fluvial plain in 50.21% of its area, whose altitude is less than 40 m, forms of flat or smooth undulating relief. In it interact the environmental effects produced by the rocky massifs of the high parts and the oscillations of the seas in the low parts. The combination of the contemporary geomorphological processes of the basin's hydrogel zones with their environmental attributes allowed the identification of homogeneous vocations of environmental services in the areas of abstraction and water regulation. As well, to identify the water effects where there is synergy between the Guandu rectified channel, built at 64 years and reserve areas around the original river bad, which were sectioned. In these places, there was an increase in upstream and downstream water flow reserve, which can be exploited for management purposes through the payment of environmental services. In the anthropogenic basin located in a region where the reservoir effects of the plain are inexpressive, the design of the water collection and management strategies in the riverbed with infiltration induction zones, through infiltration tanks, functioned as sediment retainers by preventing the emission of 29,000 t in 4 years. In addition to guaranteeing the supply of the average demand of 90 m3d-1 of raw water in a sparsely populated region with rainfall irregularity, historically exploited by subsistence agriculture, located in the peri-urban region of the RMRJ and with a predominantly negative annual climatic water balance, evidencing its potential to produce water under unfavorable conditions. / Nas plan?cies fl?vio marinha, presente ao longo da costa brasileira, existem intera??o intr?nseca entre os agentes coordenados pelas a??es do mar e a din?mica fluvial. Estas interagem e oferece quantidade e qualidade de servi?os ambientais ?s suas bacias hidrogr?ficas. Este estudo caracterizou a Bacia Hidrogr?fica do Sistema Guandu (BHSG) e sua plan?cie em rela??o a oferta de servi?os ecossist?micos. Posteriormente, prospectou sobre os fatores que determinam a oferta e manejo de servi?os como ativos ambientais em microbacias, fortemente antropizada por atividade mineral. Foram utilizadas informa??es de geoprocessamento para espacializar ?reas com servi?os ecossist?micos similares e sistema de monitoramento local para avaliar e dimensionar os servi?os ambientais. A BHSG abriga a plan?cie fl?vio marinha de Sepetiba em 50,21% de sua ?rea, cuja altitude ? inferior a 40 m, apresenta-se formas de relevo plano ou suave ondulado. Nela interagem os efeitos ambientais produzidos pelos maci?os rochosos das partes altas e as oscila??es dos mares nas partes baixas. A combina??o dos processos geomorfol?gicos contempor?neos das zonas hidrogen?ticas da bacia com seus atributos ambientais permitiu identificar voca??es homog?neas de presta??o de servi?os ambientais nas ?reas de capta??o e regula??o h?drica. Assim como, identificar os efeitos h?dricos onde h? sinergia entre o canal retificado do Guandu, constru?do a 64 anos e ?reas de reserva??o no entorno dos talvegues originais, que foram seccionados. Nestes locais, observou-se aumento da reserva??o dos fluxos h?dricos ? montante e diminui??o a jusante, que podem ser explorados para fins de manejo via pagamento de servi?os ambientais. Na bacia antropizada situado em regi?o onde os efeitos de reserva??o da plan?cie ? inexpressivo, o desenho das estrat?gias de coleta e administra??o h?drica nos talvegues com zonas de indu??o de infiltra??o, por meio de tanques de infiltra??es, funcionaram como retentores de sedimentos ao impedir a emiss?o de 29.000 t em 4 anos. Al?m de garantir o abastecimento da demanda m?dia de 90 m3d-1 de ?gua bruta em regi?o de escassa e com irregularidade de chuvas, explorada historicamente por agricultura de subsist?ncia, situada em regi?o periurbana da RMRJ e com balan?o h?drico climatol?gico anual predominantemente negativo no tempo, evidenciando o seu potencial de produ??o de ?gua em condi??es desfavor?veis
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L’utilisation des rizières par les canards hivernants : vers une gestion des rizières en interculture favorable aux canards et aux agriculteurs / The use of rice fields by wintering ducks : towards mutual benefits for ducks and farmers

Pernollet, Claire 24 February 2016 (has links)
Les rizières constituent des habitats favorables pour les oiseaux d’eau, en particulier en tant que halte migratoire, zone de reproduction ou site d’alimentation hivernal. Dans ce dernier cas, la disponibilité des ressources alimentaires (grains de riz non ramassés, graines d’adventices ou invertébrés) semble être fortement influencée par les pratiques culturales post-récolte. Ce projet vise à tester des pratiques post-récolte alternatives au brûlage-labour traditionnellement mis en place en Camargue afin de mesurer les conséquences en termes de disponibilité de nourriture et de fréquentation des parcelles par les canards hivernants. Différents traitements post-récolte (inondation, brûlage, labour, disquage et leurs combinaisons) ont été testés. Nous avons réalisé un suivi de la quantité de graines (riz, adventices) disponibles au cours du temps, depuis la récolte en Septembre-Octobre jusqu'en Mars ainsi qu’un suivi de l'usage des parcelles par les canards pendant la journée et pendant la nuit. En parallèle, nous avons étudié les bénéfices agronomiques potentiels de certaines pratiques en interculure et nous avons cherché à identifier une solution mutuellement bénéfique, répondant aux besoins d’habitat d'hivernage des canards et à ceux des riziculteurs, le tout à moindre coût. / Rice fields provide foraging habitat to waterfowl during migration, breeding and wintering seasons. In the latter case, food availability (waste rice, weed seeds or invertebrates) seems to be strongly influenced by post-harvest agricultural practices. This project aims at testing alternative post-harvest practices to the traditional burning-mowing in the Camargue in order to assess their consequences in terms of food availability and field use by wintering ducks. Different post-harvest treatments (flooding, burning, mowing, disking and their combinations) were conducted. The amount of seeds (rice + weeds) available through time was assessed, from harvest in Sept-Oct until March, and duck use of these fields during the day and during the night was simultaneously monitored. In parallel, we studied potential agronomic benefit of specific post harvest practices and we searched a mutually beneficial solution that provides needed wintering ducks habitat and is acceptable to rice farmers with limited costs.
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<i>In Rhizomia</i> : Actors, Networks and Resilience in Urban Landscapes

Ernstson, Henrik January 2008 (has links)
<p>With accelerating urbanization it is crucial to understand how urban ecosystems play a part in generating ecosystem services for urban dwellers, such as clean water, spaces for recreation, stress relief and improved air quality. An equally important question relate to who gets to enjoy these benefits, i.e. the distribution of ecosystem services, and how issues of power and equity influence the management of ecosystems. Through case studies from the urban landscape of Stockholm, this doctoral thesis engages with these perspectives through combining ecological theory with social theory, including social network analysis, actor-network theory and social movement theory. Strategies for how to improve urban ecosystem management are presented along with frameworks for how to analyze issues of power and equity in relation to natural resource management.</p><p><b>Paper I </b>shows that ecosystem management can be studied through analyzing the structure of social networks, i.e. the patterns of relations between agencies, stake-holders and user groups. <b>Paper II</b> and <b>Paper III</b> analyze, based on a network survey of 62 civil society organizations and in-depth interviews, a transformational process of how an urban local movement managed to protect a large urban green area from exploitation (The Stockholm National Urban Park). <b>Paper IV</b> discusses, based on several case studies from Stockholm, a conducive network structure for linking managers and user groups (e.g. allotment gardens, cemetery managers, and urban planners) across spatial ecological scales so as to improve urban green area management. <b>Paper V</b> presents a framework to analyze the social-ecological dynamics behind the generation and distribution of ecosystem services in urban landscapes.</p><p>The thesis points towards the notion of "a social production of ecosystem services" and argues for deeper engagement with urban political ecology and critical geography to inform governance and collective action in relation to urban ecosystems.</p>

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