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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.
1

Testing the water: How communities value, use, impact and manage water-related ecosystem services originating in an urban protected area

Brill, Gregg January 2017 (has links)
Freshwater ecosystems and their associated landscape features found in developing cities and urban protected areas are essential components of urban social-ecological systems providing city residents with cultural, provisioning and regulating services, all of which hold value. Understanding these values requires overcoming conceptual and methodological challenges so that the multi-dimensional nature, relating to the varying values, benefits, and trade-offs are understood. Understanding values, benefits and trade-offs is essential for ensuring informed and effective management of these services and the landscapes that provide them. This requires the development of tools and methods to predict how changes in land-use and management practices might affect the provision of such services. This study contributes to both the methodological and empirical literature by developing integrated and multidisciplinary approaches to assessing the beneficiaries of freshwater ecosystem services in an urban context and recognising the ecological, social and economic values assigned to ecosystem services over multiple spatial and temporal scales. The aim of this thesis was to assess how beneficiaries, stakeholders and managers within a developing city context, recognise, value and manage the multiple diverse ecosystems services associated with freshwater ecosystems as provided by different landscape features originating in an urban protected area. This aim was achieved by establishing who the beneficiaries of freshwater ecosystem services are, uncovering the spatial and temporal relationships these beneficiaries have with landscape features, determining the nature of ecosystem service values, benefits, impacts and trade-offs as experienced by the different users, as well as analysing the management policies and practices associated with urban ES. Drawing on accumulated as well as existing data sets, newly developed methods and approaches were implemented in this study. This work was primarily undertaken in Table Mountain National Park and in Cape Town, South Africa. A comparative analysis of the perceptions of park managers toward ecosystem service governance and management was undertaken in Table Mountain National Park and in Tijuca National Park, in Rio de Janeiro, Brazil. Natural freshwater ecosystems (e.g. rivers), particularly when combined with built infrastructure (e.g. dams), provide highly valued features in landscapes, delivering multiple cultural services to city residents. Recreation, aesthetic and existence services were valued highest by respondents. People who live closer to the park use, and benefit from, the park's freshwater ecosystems more frequently than those living further away. Park visitors want ease of access in terms of distance to specific freshwater ecosystems, and then once there they want a diversity of activity options, such as recreation opportunities as well as places to reflect and meditate. The outcomes of the cultural-service study in this thesis have important management implications where insights gained can guide management to ensure equitable and sustainable ecosystem service provision to all city residents. To enhance the management of ecosystem services in urban protected areas, it is important to understand the level of inclusion of the ecosystem-service concept in park policy and daily practice. Although management perceptions correspond well with park policy, the concept of ecosystem services is still narrowly developed and needs to be better integrated into the management structures and activities of Table Mountain National Park and Tijuca National Park. Outcomes from this study show that management attention relating to fresh water is still primarily focussed on biodiversity conservation and maintaining system processes and functions. Implementing and enacting the ecosystem services concept largely still needs to happen within parks and urban interfaces. The lack of communication between managers and stakeholders of protected areas makes identifying the beneficiaries of fresh water and valuing ecosystem services difficult, especially when water and associated services flow outside of the park boundaries. An important component of this study was to determine the changes to ecosystem service provision as fresh water flows from a protected area into and across an urban landscape. A scoring system was developed to determine whether changes in land use along three case-study rivers in Cape Town, all of which originate in Table Mountain National Park, positively or negatively impact the provision of water-related ecosystem services. Changes in service provision, over time, were compared to changes in long-term water quality data to verify results from the scoring system. Generally, service levels increased over time along the upper river reaches, whereas the middle and lower reaches of the rivers showed overall declines. The changes to service provision influence the value that urban residents assign to rivers. Findings in this study suggest that the provision of cultural ecosystem services as well as the protection of biological diversity were the key factors considered by those living along the case study rivers as reasons for being willing to pay to protect rivers. Provisioning services were shown to be of less value, as were the economic contribution to property values based on river frontage. This study supports the call for more innovative research to be undertaken in developing countries to break new ground and provide more comprehensive analyses to further our understanding of the values of urban ES. The challenge for environmental researchers in this context is to intensify efforts to understand the relationships between specific landscape elements and freshwater ecosystems and human perceptions, feelings and interpretations, and to express these relationships in ways that are useful for environmental policy and management.
2

Understanding of the value of the Ecosystem services for more sustainable water strategy : A case study of Water quality of the Lake Vänern in Kristinehamn Municipality

Kwizera, Prudence January 2011 (has links)
Natural resources management is one of the world‟s greatest concerns. It is a difficult task due to its complex nature. Natural resources are limited and scarce. Unfortunately and worst of all, they are under pressure, and stress due to unprecedented increase in their demand and inefficient use. But it is still possible to tackle this complex problem. This study focuses on understanding the value of the ecosystem services that human well-being depend on, as for more sustainable environment strategy on aquatic ecosystems management, such as lakes and rivers. Changing behavior and attitude can be a crucial complement and likely can stimulate our conscious effort towards saving our ecosystems beyond money contribution. This way of thinking seems to be overlooked and most people think that the development of technology and advancement in knowledge alone can provide solution. One way to overcome the problem of pressure and stressing of the environment is to develop adequate strategy and environmental policy. This policy should include economics measures where, when necessary and feasible. Since there are "no one solution and no one answer" to achieve the desired outcome of a sustainable future, it becomes necessary to adopt a multidisciplinary approach to environmental management and the understanding of the value and dynamism change of the ecosystem services. Adoption of efficient management is not enough; we have to adjust our attitude as well. To discuss this issue, the aquatic ecosystem, which the lake Vänern in Kristinehamn Municipality served as a case study.
3

Domestic Livestock and Rewilding: Are They Mutually Exclusive?

Gordon, Iain J., Manning, Adrian D., Navarro, Laetitia M., Rouet-Leduc, Julia 30 March 2023 (has links)
Human influence extends across the globe, fromthe tallestmountains to the deep bottom of the oceans. There is a growing call for nature to be protected from the negative impacts of human activity (particularly intensive agriculture); so-called “land sparing”. A relatively new approach is “rewilding”, defined as the restoration of self-sustaining and complex ecosystems, with interlinked ecological processes that promote and support one another while minimising or gradually reducing human intervention. The key theoretical basis of rewilding is to return ecosystems to a “natural” or “self-willed” state with trophic complexity, dispersal (and connectivity) and stochastic disturbance in place. However, this is constrained by context-specific factors whereby it may not be possible to restore the native species that formed part of the trophic structure of the ecosystem if they are extinct (e.g., mammoths, Mammuthus spp., aurochs, Bos primigenius); and, populations/communities of native herbivores/predators may not be able to survive or be acceptable to the public in small scale rewilding projects close to areas of high human density. Therefore, the restoration of natural trophic complexity and disturbance regimes within rewilding projects requires careful consideration if the broader conservation needs of society are to be met. In some circumstances, managers will require a more flexible deliberate approach to intervening in rewilding projects using the range of tools in their toolbox (e.g., controlled burning regimes; using domestic livestock to replicate the impacts of extinct herbivore species), even if this is only in the early stages of the rewilding process. If this approach is adopted, then larger areas can be given over to conservation, because of the potential broader benefits to society from these spaces and the engagement of farmers in practises that are closer to their traditions. We provide examples, primarily European, where domestic and semi-domestic livestock are used by managers as part of their rewilding toolbox. Here managers have looked at the broader phenotype of livestock species as to their suitability in different rewilding systems. We assess whether there are ways of using livestock in these systems for conservation, economic (e.g., branded or certified livestock products) and cultural gains.
4

Dinâmica da retenção de nitrogênio e fósforo em riachos tropicais do bioma Cerrado (SP) / Nitrogen and phosphorous uptake dynamics in tropical streams from Cerrado biome (SP, Brazil)

Finkler, Nícolas Reinaldo 27 March 2018 (has links)
Os serviços ecossistêmicos se traduzem em benefícios diretos e indiretos obtidos pelos seres humanos do ambiente natural graças ao papel imprescindível dos ecossistemas para o seu bem-estar, saúde e desenvolvimento socioeconômico. Considerando o serviço ecossistêmico de purificação da água, a retenção de nitrogênio e fósforo pelos ecossistemas aquáticos depende de uma combinação de mecanismos físicos, químicos e biológicos que transformam o nutriente no sentido longitudinal de um curso de água. A retenção é majoritariamente estudada em ambientes temperados, mas ainda pouco se sabe sobre como as características ambientais de sistemas tropicais podem afetá-la. O objetivo principal dessa pesquisa foi estimar a retenção de macronutrientes em riachos localizados no bioma Cerrado (SP). Avaliaram-se, além das características físicas e químicas, as taxas de retenção de nitrato, amônio e fosfato em trechos de quatro riachos caracterizados por gradientes de concentrações ambientais para testar hipóteses vinculadas ao nível de enriquecimento por nutrientes e ao papel de riachos tropicais sobre a retenção ecossistêmica. No período de janeiro a outubro de 2017, foram realizados pulsos de nutrientes, segundo o método Tracer Additions for Spiraling Curve Characterization, para modelagem e quantificação de métricas de retenção desses nutrientes (distância, taxa e velocidade de retenção em condições ambientais), além do comportamento cinético de cada adição. Os riachos foram hierarquizados conforme o nível de enriquecimento por fosfato, variável utilizada como discriminante de tal enriquecimento em função de sua significativa variação inter-riachos. Com relação às métricas de retenção, foram encontradas diferenças espaciais significativas entre riachos, enquanto que não foram observadas diferenças temporais entre coletas. Em geral, riachos não enriquecidos apresentaram distâncias de retenção em geral menores (8-418 m para nitrato, 38-172 m para amônio e de 60-560 m para fosfato) em comparação a ambientes enriquecidos (56-508 m para nitrato, 35-253 m para amônio e de 77-391 m para fosfato). Além disso, os riachos não enriquecidos apresentaram maior velocidade de retenção (máximas de 123 mm min-1 para nitrato, 68 mm min-1 para amônio e 17 mm min-1 para fosfato), além de taxas de retenção (µg m-2 min-1) superiores em comparação aos enriquecidos. O nitrato apresentou maiores taxas ambiental de retenção (média geométrica de 999,3 µg m-2 min-1), enquanto o amônio apresentou menor distância ambiental de retenção (média geométrica de 85,7 m) e maior velocidade ambiental de retenção (média geométrica de 6,9 mm min-1). No ajuste cinético da retenção, não foi evidenciada a saturação de concentrações para nenhum caso. O modelo Efficiency-Loss mostrou melhor ajuste cinético aos dados experimentais que os modelos cinéticos de Michaelis-Menten e primeira ordem. As métricas de retenção obtidas são de magnitudes superiores às normalmente reportadas na literatura para riachos de pequeno porte em outros biomas, o que reforça a importância da preservação e conservação de riachos tropicais. Para isso, sugere-se especial atenção ao controle e disciplinamento das formas de uso e ocupação do solo nestas bacias. Concluiu-se que os riachos analisados desempenham um papel relevante como sumidouros de N e P, o que os permite colocar na categoria de cursos de água estratégicos em relação ao serviço ambiental de retenção de nutrientes. . / Aquatic systems are responsible for key ecosystems services, providing direct and indirect benefits for human beings such as well-being, health and socio-economic development. The ecosystem service of water purification is one of their main functions. Nutrient uptake in surface waters is a combination of physical, chemical and biological mechanisms which transform the nutrient in a downstream direction. The nutrient uptake has been mostly studied in temperate environments, but little is known about how the environmental characteristics of tropical systems could affect it. The main objective of this study was to estimate the nutrient uptake in streams located in the Cerrado biome (SP). In addition to the physical and chemical characteristics, nitrate, ammonium and phosphate uptake rates were evaluated in reaches of four streams characterized by gradients of environmental concentrations. Also we tested hypotheses regarding the level of nutrient enrichment and the role of tropical streams on the whole ecosystem uptake. From January to October 2017, nutrient additions were carried out according to the Tracer Additions for Spiraling Curve Characterization method, in order to model and quantify nutrient uptake metrics (uptake lenght, uptake rate and uptake velocity under ambient conditions) and to characterize the kinetics of each addition. The streams were ranked according to the level of enrichment by phosphate, since its concentrations showed significant variation across streams. Significant spatial differences were found across streams, while no temporal differences were observed among sampling periods. In general, non-enriched streams generally had lower uptake lengths (8-418 m for nitrate, 38-172 m for ammonium and 60-560 m for phosphate) in comparison to enriched streams (56-508 m for nitrate, 35 -253 m for ammonium and 77-391 m for phosphate). Non-enriched streams showed higher uptake velocities (maximum of 123 mm min-1 for nitrate, 68 mm min-1 for ammonium and 17 mm min-1 for phosphate), as well as uptake rates (µg m-2 min-1) greater than enriched streams. Nitrate had higher ambient uptake rates (geometric mean of 999.3 µg m-2 min-1), while ammonium had lower ambient uptake length (geometric mean of 85.7 m) and higher ambient uptake velocity (geometric mean of 6.9 mm min-1). The uptake kinetics modelling suggested that no nutrient saturation occurred in any case. The Efficiency-Loss kinetic model had better fit to the experimental data than Michaelis-Menten and first-order kinetic models. The retention metrics obtained are higher than those normally reported in the literature for low-order streams in other biomes, which highlights the importance of preservation and conservation of tropical streams. Special attention should be given to the control and management of the land use forms in these watersheds. The studied streams play a relevant role as sinks of N and P, indicating they are strategic watercourses regarding the environmental service of nutrient uptake.
5

Potencial de contribuição de espécies nativas de hábitos distintos para o controle de erosão e restauração de margens de corpos hídricos / Potential contribution of native species of different habits for erosion controlling and restoration of water body margins

Hirose, Alice Takako 03 October 2013 (has links)
Espécies nativas de hábitos herbáceo, subarbustivo, arbustivo e liana de rápido crescimento podem exercer papel importante em práticas visando o controle de erosão para a restauração de margens de corpos hídricos, principalmente onde a regeneração natural é mais difícil, em áreas muito perturbadas, onde a declividade do terreno é mais acentuada e os processos erosivos em diques marginais são mais intensos. O presente trabalho teve como objetivo avaliar o potencial de aplicação de espécies nativas de diferentes hábitos em testes visando o controle de erosão para restauração de margens de corpos hídricos. No cap.2 foram propostos alguns critérios de seleção de espécies, com sugestão de estrutura metodológica identificando algumas \"características/atributos\" e \"funções\", bem como avaliação preliminar de 43 táxons no contexto da região de estudo. Complementarmente, foram montados alguns experimentos expeditos: cap.3: Avaliação do potencial de germinação e produção de mudas em viveiro a partir de sementes coletadas de 07 espécies nativas subarbustivas e arbustivas (citado no cap.2: \"potencial de propagação\"); e cap.4: Avaliação do desenvolvimento de 08 espécies herbáceas, arbustivas e liana, após submeter o sistema radicular destas a condições distintas de saturação hídrica do substrato (citado no cap.2: \"ambiente de ocorrência das espécies\"). Dentre os 43 táxons: 35 apresentaram características morfológicas do sistema aéreo de interesse para aplicação em experimentos visando o controle de processos erosivos, sendo: 22 de origem pluvial para proteção superficial e subsuperficial de diques marginais, outros 11 de origem fluvial e também pluvial (por meio de barreiras ou faixas vegetais em combinação com os demais tipos) para a proteção da base e bordas de diques marginais; 31 para experimentos visando a recuperação do solo: 10 leguminosas nodulíferas, 21 para cobertura e retenção de umidade; 31 para input de matéria orgânica; e 20 visando a recuperação de diversidade fornecendo recursos para a fauna (cap.2). Dentre 07 espécies avaliadas, a maioria demonstrou potencial para germinação e formação de mudas em de viveiro: 06 apresentaram tolerância ao armazenamento (24-28 meses); 02 conseguiram germinar naturalmente em viveiro em até 14 dias, com elevados percentuais de germinação e preferência por períodos mais quentes do ano para germinar, enquanto outras 02 foram mais lentas (30-60 dias); 03 espécies demonstraram requerer tratamento pré-germinativo para a quebra de dormência tegumentar (cap.3). Para 08 espécies verificaram-se 05 padrões quanto a preferências hídricas. Os resultados quanto ao desenvolvimento de biomassa nos tratamentos corroboraram com grande parte das observações em campo (cap.4). Recomenda-se a realização de estudos que elucidem o papel funcional de espécies nativas de hábitos distintos, identificando e mensurando características e/ou atributos que lhes possibilitam conter fluxos hídricos, desagregação e transporte de sedimentos, sendo os serviços ecossistêmicos de proteção do solo e controle de erosão um primeiro passo para etapas seguintes da restauração. / Native species of herbaceous habits, subshrub, shrub and liana of rapid growth may play an important role in practices aimed at controlling erosion to restore margins of water bodies, especially where natural regeneration is more difficult, as well as in very disturbed areas, where slopes are steeper and where pluvial and fluvial erosion in river banks are more intense. Considering the lack of studies with this focus, this study had the aim of evaluating the potential application of native species of different habits in tests for controlling erosion and restoring water body margins. In chapter 2 some species selection criteria were suggested as well as methodological framework identifying some \"characteristics / attributes\" and \"functions\" besides a preliminary evaluation of 43 taxa in the context of the study region. Additionally, some expeditious experimental work was done: chapter 3: Potential for germination and seedling production in the nursery with seeds collected from 07 native subshrubs and shrubs species (referring to \"propagation potential\" quoted in chapter 2) and chapter 4: Development of 08 species: subshrub, shrub and liana, after conditioning the root system of these plants through different conditions of substrate water saturation(referring to \"environment of species occurrence\" quoted in chapter 2). Among the 43 taxa: 35 showed morphological aerial or shoot system characteristics which were of interest for application in erosion control experiments, 22 of pluvial origin, for surface and subsurface river bank protection (and slopes), 11 others had fluvial and pluvial origin(through barriers or vegetable strips in combination with other types) to protect the base and edges of river banks (and slopes); 31 for soil recovering experiments, distributed as follows: 10 nodulating Fabaceae species, 21 to provide coverage and moisture retention, 31 to organic matter input; 21 for diversity recovering experiments, to supply resources for wildlife (chapter 2). Among the 07 species assessed, most of them demonstrated germination potential as well as potential for seedling formation in the nursery: 06 tolerated storage (24-28 months), 02 were able to germinate naturally in the nursery within 14 days with high germination rates and preference for warmer periods of the year to germinate, while the other 02 were slower (30-60 days); 03 species required pre germination treatments for breaking cutaneous dormancy (chapter 3). For 08 species 05 patterns of hydric preferences were observed. The results for biomass development along the treatments corroborate withgreat part of the field observations (chapter 4). In the future we recommend that studies to elucidate the functional role of native species of different habits be carried out, they should identify and measure features and / or attributes that enable the plants to contain hydric flows, sediment transport and retention. These ecosystem services of soil protection and erosion control are the first step towards next restoration stages.
6

Dinâmica da retenção de nitrogênio e fósforo em riachos tropicais do bioma Cerrado (SP) / Nitrogen and phosphorous uptake dynamics in tropical streams from Cerrado biome (SP, Brazil)

Nícolas Reinaldo Finkler 27 March 2018 (has links)
Os serviços ecossistêmicos se traduzem em benefícios diretos e indiretos obtidos pelos seres humanos do ambiente natural graças ao papel imprescindível dos ecossistemas para o seu bem-estar, saúde e desenvolvimento socioeconômico. Considerando o serviço ecossistêmico de purificação da água, a retenção de nitrogênio e fósforo pelos ecossistemas aquáticos depende de uma combinação de mecanismos físicos, químicos e biológicos que transformam o nutriente no sentido longitudinal de um curso de água. A retenção é majoritariamente estudada em ambientes temperados, mas ainda pouco se sabe sobre como as características ambientais de sistemas tropicais podem afetá-la. O objetivo principal dessa pesquisa foi estimar a retenção de macronutrientes em riachos localizados no bioma Cerrado (SP). Avaliaram-se, além das características físicas e químicas, as taxas de retenção de nitrato, amônio e fosfato em trechos de quatro riachos caracterizados por gradientes de concentrações ambientais para testar hipóteses vinculadas ao nível de enriquecimento por nutrientes e ao papel de riachos tropicais sobre a retenção ecossistêmica. No período de janeiro a outubro de 2017, foram realizados pulsos de nutrientes, segundo o método Tracer Additions for Spiraling Curve Characterization, para modelagem e quantificação de métricas de retenção desses nutrientes (distância, taxa e velocidade de retenção em condições ambientais), além do comportamento cinético de cada adição. Os riachos foram hierarquizados conforme o nível de enriquecimento por fosfato, variável utilizada como discriminante de tal enriquecimento em função de sua significativa variação inter-riachos. Com relação às métricas de retenção, foram encontradas diferenças espaciais significativas entre riachos, enquanto que não foram observadas diferenças temporais entre coletas. Em geral, riachos não enriquecidos apresentaram distâncias de retenção em geral menores (8-418 m para nitrato, 38-172 m para amônio e de 60-560 m para fosfato) em comparação a ambientes enriquecidos (56-508 m para nitrato, 35-253 m para amônio e de 77-391 m para fosfato). Além disso, os riachos não enriquecidos apresentaram maior velocidade de retenção (máximas de 123 mm min-1 para nitrato, 68 mm min-1 para amônio e 17 mm min-1 para fosfato), além de taxas de retenção (µg m-2 min-1) superiores em comparação aos enriquecidos. O nitrato apresentou maiores taxas ambiental de retenção (média geométrica de 999,3 µg m-2 min-1), enquanto o amônio apresentou menor distância ambiental de retenção (média geométrica de 85,7 m) e maior velocidade ambiental de retenção (média geométrica de 6,9 mm min-1). No ajuste cinético da retenção, não foi evidenciada a saturação de concentrações para nenhum caso. O modelo Efficiency-Loss mostrou melhor ajuste cinético aos dados experimentais que os modelos cinéticos de Michaelis-Menten e primeira ordem. As métricas de retenção obtidas são de magnitudes superiores às normalmente reportadas na literatura para riachos de pequeno porte em outros biomas, o que reforça a importância da preservação e conservação de riachos tropicais. Para isso, sugere-se especial atenção ao controle e disciplinamento das formas de uso e ocupação do solo nestas bacias. Concluiu-se que os riachos analisados desempenham um papel relevante como sumidouros de N e P, o que os permite colocar na categoria de cursos de água estratégicos em relação ao serviço ambiental de retenção de nutrientes. . / Aquatic systems are responsible for key ecosystems services, providing direct and indirect benefits for human beings such as well-being, health and socio-economic development. The ecosystem service of water purification is one of their main functions. Nutrient uptake in surface waters is a combination of physical, chemical and biological mechanisms which transform the nutrient in a downstream direction. The nutrient uptake has been mostly studied in temperate environments, but little is known about how the environmental characteristics of tropical systems could affect it. The main objective of this study was to estimate the nutrient uptake in streams located in the Cerrado biome (SP). In addition to the physical and chemical characteristics, nitrate, ammonium and phosphate uptake rates were evaluated in reaches of four streams characterized by gradients of environmental concentrations. Also we tested hypotheses regarding the level of nutrient enrichment and the role of tropical streams on the whole ecosystem uptake. From January to October 2017, nutrient additions were carried out according to the Tracer Additions for Spiraling Curve Characterization method, in order to model and quantify nutrient uptake metrics (uptake lenght, uptake rate and uptake velocity under ambient conditions) and to characterize the kinetics of each addition. The streams were ranked according to the level of enrichment by phosphate, since its concentrations showed significant variation across streams. Significant spatial differences were found across streams, while no temporal differences were observed among sampling periods. In general, non-enriched streams generally had lower uptake lengths (8-418 m for nitrate, 38-172 m for ammonium and 60-560 m for phosphate) in comparison to enriched streams (56-508 m for nitrate, 35 -253 m for ammonium and 77-391 m for phosphate). Non-enriched streams showed higher uptake velocities (maximum of 123 mm min-1 for nitrate, 68 mm min-1 for ammonium and 17 mm min-1 for phosphate), as well as uptake rates (µg m-2 min-1) greater than enriched streams. Nitrate had higher ambient uptake rates (geometric mean of 999.3 µg m-2 min-1), while ammonium had lower ambient uptake length (geometric mean of 85.7 m) and higher ambient uptake velocity (geometric mean of 6.9 mm min-1). The uptake kinetics modelling suggested that no nutrient saturation occurred in any case. The Efficiency-Loss kinetic model had better fit to the experimental data than Michaelis-Menten and first-order kinetic models. The retention metrics obtained are higher than those normally reported in the literature for low-order streams in other biomes, which highlights the importance of preservation and conservation of tropical streams. Special attention should be given to the control and management of the land use forms in these watersheds. The studied streams play a relevant role as sinks of N and P, indicating they are strategic watercourses regarding the environmental service of nutrient uptake.
7

Potencial de contribuição de espécies nativas de hábitos distintos para o controle de erosão e restauração de margens de corpos hídricos / Potential contribution of native species of different habits for erosion controlling and restoration of water body margins

Alice Takako Hirose 03 October 2013 (has links)
Espécies nativas de hábitos herbáceo, subarbustivo, arbustivo e liana de rápido crescimento podem exercer papel importante em práticas visando o controle de erosão para a restauração de margens de corpos hídricos, principalmente onde a regeneração natural é mais difícil, em áreas muito perturbadas, onde a declividade do terreno é mais acentuada e os processos erosivos em diques marginais são mais intensos. O presente trabalho teve como objetivo avaliar o potencial de aplicação de espécies nativas de diferentes hábitos em testes visando o controle de erosão para restauração de margens de corpos hídricos. No cap.2 foram propostos alguns critérios de seleção de espécies, com sugestão de estrutura metodológica identificando algumas \"características/atributos\" e \"funções\", bem como avaliação preliminar de 43 táxons no contexto da região de estudo. Complementarmente, foram montados alguns experimentos expeditos: cap.3: Avaliação do potencial de germinação e produção de mudas em viveiro a partir de sementes coletadas de 07 espécies nativas subarbustivas e arbustivas (citado no cap.2: \"potencial de propagação\"); e cap.4: Avaliação do desenvolvimento de 08 espécies herbáceas, arbustivas e liana, após submeter o sistema radicular destas a condições distintas de saturação hídrica do substrato (citado no cap.2: \"ambiente de ocorrência das espécies\"). Dentre os 43 táxons: 35 apresentaram características morfológicas do sistema aéreo de interesse para aplicação em experimentos visando o controle de processos erosivos, sendo: 22 de origem pluvial para proteção superficial e subsuperficial de diques marginais, outros 11 de origem fluvial e também pluvial (por meio de barreiras ou faixas vegetais em combinação com os demais tipos) para a proteção da base e bordas de diques marginais; 31 para experimentos visando a recuperação do solo: 10 leguminosas nodulíferas, 21 para cobertura e retenção de umidade; 31 para input de matéria orgânica; e 20 visando a recuperação de diversidade fornecendo recursos para a fauna (cap.2). Dentre 07 espécies avaliadas, a maioria demonstrou potencial para germinação e formação de mudas em de viveiro: 06 apresentaram tolerância ao armazenamento (24-28 meses); 02 conseguiram germinar naturalmente em viveiro em até 14 dias, com elevados percentuais de germinação e preferência por períodos mais quentes do ano para germinar, enquanto outras 02 foram mais lentas (30-60 dias); 03 espécies demonstraram requerer tratamento pré-germinativo para a quebra de dormência tegumentar (cap.3). Para 08 espécies verificaram-se 05 padrões quanto a preferências hídricas. Os resultados quanto ao desenvolvimento de biomassa nos tratamentos corroboraram com grande parte das observações em campo (cap.4). Recomenda-se a realização de estudos que elucidem o papel funcional de espécies nativas de hábitos distintos, identificando e mensurando características e/ou atributos que lhes possibilitam conter fluxos hídricos, desagregação e transporte de sedimentos, sendo os serviços ecossistêmicos de proteção do solo e controle de erosão um primeiro passo para etapas seguintes da restauração. / Native species of herbaceous habits, subshrub, shrub and liana of rapid growth may play an important role in practices aimed at controlling erosion to restore margins of water bodies, especially where natural regeneration is more difficult, as well as in very disturbed areas, where slopes are steeper and where pluvial and fluvial erosion in river banks are more intense. Considering the lack of studies with this focus, this study had the aim of evaluating the potential application of native species of different habits in tests for controlling erosion and restoring water body margins. In chapter 2 some species selection criteria were suggested as well as methodological framework identifying some \"characteristics / attributes\" and \"functions\" besides a preliminary evaluation of 43 taxa in the context of the study region. Additionally, some expeditious experimental work was done: chapter 3: Potential for germination and seedling production in the nursery with seeds collected from 07 native subshrubs and shrubs species (referring to \"propagation potential\" quoted in chapter 2) and chapter 4: Development of 08 species: subshrub, shrub and liana, after conditioning the root system of these plants through different conditions of substrate water saturation(referring to \"environment of species occurrence\" quoted in chapter 2). Among the 43 taxa: 35 showed morphological aerial or shoot system characteristics which were of interest for application in erosion control experiments, 22 of pluvial origin, for surface and subsurface river bank protection (and slopes), 11 others had fluvial and pluvial origin(through barriers or vegetable strips in combination with other types) to protect the base and edges of river banks (and slopes); 31 for soil recovering experiments, distributed as follows: 10 nodulating Fabaceae species, 21 to provide coverage and moisture retention, 31 to organic matter input; 21 for diversity recovering experiments, to supply resources for wildlife (chapter 2). Among the 07 species assessed, most of them demonstrated germination potential as well as potential for seedling formation in the nursery: 06 tolerated storage (24-28 months), 02 were able to germinate naturally in the nursery within 14 days with high germination rates and preference for warmer periods of the year to germinate, while the other 02 were slower (30-60 days); 03 species required pre germination treatments for breaking cutaneous dormancy (chapter 3). For 08 species 05 patterns of hydric preferences were observed. The results for biomass development along the treatments corroborate withgreat part of the field observations (chapter 4). In the future we recommend that studies to elucidate the functional role of native species of different habits be carried out, they should identify and measure features and / or attributes that enable the plants to contain hydric flows, sediment transport and retention. These ecosystem services of soil protection and erosion control are the first step towards next restoration stages.
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Nouvelles comptabilités au service des écosystèmes. Une recherche engagée auprès d'une entreprise du secteur de l'environnement. / New management accounting for ecosystems. An action research with an environmental sector company.

Feger, Clément 17 February 2016 (has links)
La lutte contre la destruction des écosystèmes et les efforts pour renforcer et renouveler les conditions de leur prise en charge collective reposent aujourd’hui sur trois fronts d’innovation disjoints : (1) la conception et l’utilisation de nouveaux outils d’évaluation des écosystèmes dans le champ de la conservation ; (2) le développement de nouvelles comptabilités socio-environnementales à l’échelle des organisations et (3) la mise à contribution des entreprises dans la protection du capital naturel. Cette thèse doctorale vise à les articuler en mobilisant la comptabilité comme pivot pour connecter les systèmes d’information écologique, les formes diverses d’organisation de l’action collective, et les initiatives et comptabilités des entreprises. Elle combine un travail de construction théorique et une recherche-intervention auprès d’une grande entreprise du secteur de l’environnement qui cherche à développer des activités de service dédiées à la qualité écologique des territoires. Nous proposons premièrement l’ouverture d’une nouvelle perspective d’innovation théorique et pratique, au croisement entre comptabilités et sciences de la conservation, et centrée sur la gestion collective de problèmes écologiques : le développement de « Comptabilités de Gestion pour les Ecosystèmes ». Nous montrons en quoi elles sont complémentaires de l’ensemble des autres types d’innovations comptables portant sur les écosystèmes. Nous proposons deuxièmement quatre grandes orientations organisationnelles et stratégiques pour penser et guider le développement de nouveaux modèles d’affaires de « services aux écosystèmes ». Afin de les compléter, nous ouvrons des pistes de conception de comptes et d’activités comptables pour accompagner une entreprise du secteur de l’environnement dans la négociation et la création collective de valeur écologique sur les territoires et dans la transformation de sa propre représentation et quantification de la valeur. / Current efforts to halt the destruction of the planet’s ecosystems and to reinforce and renew their collective management reside on three distinct innovation fronts: (1) the design and use of new ecosystem assessment tools by conservation scientists and practitioners; (2) the development of new social and environmental accounting frameworks and tools at the level of organization; (3) the contribution of the private sector to natural capital protection and maintenance. This doctoral thesis aims to relate these three domains of innovation to one another by mobilizing the accounting discipline as a pivot to connect ecological information systems and tools, diverse forms of collective action for ecosystem management, and private sector initiatives and accounting innovations. The thesis combines a work of theoretical construction with the results of an action-research conducted in an environmental sector company that seeks to develop new services specifically designed for the management of ecological systems. We first propose a new theoretical and practical perspective at the junction of accounting and conservation science centered on the collective management of ecological issues: the development of Management Accounting for Ecosystems. We show why and how they are complementary to all the other domains of ecosystem accounting innovation. Secondly, we introduce four organizational and strategic directions to think and guide the development of new “services to ecosystems” business models. To complement them, we suggest new accounts and accounting practices to help environmental sector companies negotiate and co-create ecological value with other stakeholders, and transform their own representation and quantification of corporate value.

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