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Hållbart nyttjande av vattenresurser på Gotland : vision och verklighetHolén, Elinor January 2011 (has links)
Fresh water has become more and more of a scarce commodity. Water scarcity isn't first and foremost a cause of drought and wasting, but a cause of inequality and mismanagement. This is not only a problem for developing countries, and there can also be variations within countries. The municipality of Gotland has a development program called Vision Gotland 2025, with goals for growth and sustainable development. The aim of this study is to examine whether the use and management of water resources on Gotland and Vision Gotland 2025 is conformed to the Water Framework Directive and the Ecosystem Approach in terms of sustainability. Focus is on the quantitative aspects of water supply. The study has mainly been done by studying publications from the authorities concerned. Although annual precipitation in general is enough to provide fresh water for the population, water shortage occurs in some areas during the summers. Three of the four main catchment areas on Gotland have unsatisfactory quantitative status, and is likely to have so also when the time limit of the next evaluation is due in 2015. Since both the population and tourism is presumed to increase, according to Vision Gotland 2025, the conclusion drawn is that the use of water resources is not sustainable, even though the management per se does conform to the ecosystem approach.
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The Future of the St. Lawrence River at Cornwall, Ontario Post-Remedial Action Plan (RAP): Navigating toward SustainabilityRITCEY, Alicia Laura 06 October 2010 (has links)
This thesis undertakes a review of the Remedial Action Plans (RAPs) for the St. Lawrence River Area of Concern (AOC). As directed by Great Lakes Water Quality Agreement, RAPs are to take a systematic and comprehensive ecosystem approach to restoration, and ensure that the public is consulted about restoration activities. Through triangulation of three different research methods: twelve semi-structured interviews, observational research, and document analysis, this research explores how these two principles were incorporated into the St. Lawrence River AOC.
This research draws from environmental management and governance literature in order to describe the implementation and decision-making frameworks of the RAP program. In theory an ecosystem approach is to be holistic and comprehensive in scope and application. In terms of the St. Lawrence River AOC, the holistic nature of the restoration process was hindered by the jurisdictional complexity of the region; Not only was there two federal governments, Canada and the United States, but the province of Ontario, state of New York, and the Mohawks of Akwesasne Nation. These jurisdictional divisions led to the eventual decision to separate the AOC into two RAPs at Massena, NY and Cornwall, ON. This division led to a divergence in impairment indicator identification and resultant restoration practices, timelines for RAP progress reports, availability of financial resources, and collective organization of restoration duties.
The goal of each RAP is to eventually delist as an AOC. Through a review of the collective organization of the Cornwall RAP, it is best described as participatory and inclusive in terms of governance. There was representation and membership from government, industry, First Nations, and the public making the Cornwall RAP an example of solidarity in action. Because there has been a unification of visions through the RAP process, which is to have a clean and health St. Lawrence River, momentum has been generated to expand the ideals of the RAP to a broader St. Lawrence River collective. Lessons learned from this restoration process are constructive for cross-jurisdictional, multi-media restoration projects and serve to inform approaches to ecosystem restoration, planning, and management, especially that of the St. Lawrence River. / Thesis (Master, Environmental Studies) -- Queen's University, 2010-09-30 15:39:18.132
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Walking the land : examining an ecosystem approach for private estates through the lens of woodland expansionBowditch, Euan A. D. January 2016 (has links)
This thesis presents a local interpretation of an ecosystem approach; 'energyscapes' constructed through mixed methods, which captures private estate manager perception on land use, woodland expansion and collaboration over four case study areas in the Scottish Highlands. Each case study area of three contiguous estates forms a small landscape cluster, with every estate participating in field interviews, woodland planning and collaborative discussions. Private estates in Scotland cover a significant area of the Highlands and are dominated by traditional sporting interests and recreation that is not always considered compatible with woodland expansion, creating a culture of woodland neglect. Subsequently planting rates are falling and Scottish government woodland expansion targets are not being met, despite large areas of vacant land. Key areas of estate and woodland resilience are identified by land managers to improve social and structural connectivity using the novel landscape resilience mapping method, which presents land manager perceptions over a spatial scale linked to resilience concepts. The Forest Energy Tool developed in response to the need for economic justification for woodland expansion demonstrates the potential profitability of local woodfuel markets, as well as providing silvicultural treatments for further management aims. Estate resilience involves fostering effective integration between sporting uses, renewable energy and enhanced rural markets, such as value added forestry. Ecosystem approaches are normally expressed through aspirational policy that is difficult to translate into relevant practice for individual land managers. Energyscapes provides meaning to ecosystem approach policy through CBD principles and operational guidelines, and local practice; including integration of hydro schemes, forest energy and carbon sequestration at estate level and bridging of local and regional scales through six land manager identified landscape partnerships. However, developing leadership, as well as expertise and social capacity in landscape management, is required to mobilise such frameworks. Fundamental to realising these local ecosystem approaches is land manager trust and confidence, which can generate support for emerging land uses alongside tradition, increasing resilience by capturing and utilising the culture embedded within the landscape.
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Aplicação da abordagem ecossistêmica ao estudo da microbacia do córrego São José (São Carlos - SP) / The ecosystem approach applied to the study of the São José stream basin (São Carlos - SP)Sidagis Galli, Corina Verónica 30 January 1998 (has links)
As bacias hidrográficas são sistemas que fornecem um tipo de unidade adequada ao estudo dos ecossistemas e permitem um melhor entendimento científico dos processos naturais. Os estudos em pequenas bacias têm mostrado a dependência da composição das águas dos riachos das características dos ecossistemas terrestres adjacentes. A microbacia formada pelos córregos Águas da Prata, Macuco e São José está localizada a sudeste da cidade de São Carlos, Estado de São Paulo, com uma área de 13,9 Km2. O córrego Macuco apresenta vários represamentos, sendo os mais importantes os reservatórios Iguá, Igaraba e Iembó. Estes córregos apresentam pequena vazão e drenam solos ácidos. O solo da região é predominantemente argiloso e arenoso e a vegetação original é o cerrado. As áreas de campo antrópico estão ocupadas por culturas em geral e áreas de pastagem e criação animais. Quanto ao clima existem dois períodos: o seco e o chuvoso. O objetivo deste trabalho foi caracterizar e avaliar a qualidade da água do ponto de vista ecológico, determinar as interrelações entre os aspectos básicos da climatologia, geologia, morfometria, hidrologia e usos e ocupação do solo na microbacia hidrográfica com as variáveis físicas,químicas e biológicas das águas dos córregos e reservatórios, além de caracterizar as comunidades planctônicas dos reservatórios. Foram realizadas coletas mensais de 09/1995 a 09/1996 em 8 pontos da microbacia, sendo que três deles foram localizados nos reservatórios que foram analisados em três profundidades (superfície, meio e fundo da coluna de água). A análise das características físicas, químicas e biológicas da água dos córregos estudados indicou que não existem diferenças significativas entre os córregos Águas da Prata e Macuco. No entanto o córrego São José foi mais diferenciado, sendo este o que se mostrou mais impactado. As concentrações de oxigênio dissolvido foram baixas no córrego Macuco e no São José. Nos locais mais afetados pelos dejetos de animais foram observados altos valores de condutividade, embora os maiores valores tenham sido registrados no córrego São José, abaixo do trecho sob influência do chorume do aterro sanitário da cidade de São Carlos. Das formas de nitrogênio o amônio foi a mais abundante para toda a microbacia. As concentrações de fosfato inorgânico e fósforo total dissolvido foram baixas, indicando a provável absorção do fósforo pelo sedimento. A construção de barragens no córrego Macuco levou ao rompimento da continuidade do sistema do rio. Os três reservatórios apresentaram uma estratificação térmica acentuada durante o período de chuvas o que causou anoxia no hipolímnio. Não foram observadas diferenças significativas nas concentrações de nutrientes entre os períodos de chuva e seca, com exceção do fósforo total e o silicato reativo. O balanço de massa dos nutrientes nos reservatórios demonstrou que o reservatório Igaraba se comporta como um sistema de retenção de nutrientes enquanto os outros dois se comportam como sistemas de exportação. Nos reservatórios a comunidade fitoplanctônica foi dominada, em termos quantitativos, pelas Bacillariophyceae e pelas Chlorophyta, sendo os grupos restantes escassos. A comunidade zooplanctônica foi dominada numericamente pelos Rotifera durante todo o período de estudos. O desenvolvimento do zooplâncton como um todo correlacionou-se positivamente com o desenvolvimento do fitoplâncton. Segundo os índices de estado trófico utilizados os reservatórios se classificam como mesotróficos. Foi observado que as atividades antrópicas, especialmente o uso inadequado do solo para a agricultura, provocam erosão e carreamento de sedimentos para os corpos de água. As instalações agro-industriais contribuem para o aumento da concentração de materiais na água de escoamento, acumulando os resíduos nos riachos e alterando a qualidade da água próxima às nascentes. / Hydrographic basins provide an adequate subject for studies of ecosystems and a better understanding of natural processes. Studies of small basins revealed that the chernical composition of stream waters are strongly dependent upon the characteristics of the surrounding land ecosystems. The rnicrobasin formed by the Águas da Prata, Macuco and São José streams is located in the Southeast portion of the city of São Carlos, State of São Paulo, and covers an area of 13,9 Km2. The Macuco stream has several reservoirs, of which the Iguá, Igaraba and Iembó reservoirs are the most important ones. These streams have a low outflow volume and they run across acid soils. The soil is predominantly formed by silt and sand, and the original plant formation was the \"cerrado\", a savanna type of vegetation. The land through which these streams flow is cultivated with several different crops as well pastures for cattle. In regard to the climate, there are two different periods: one dry, lasting from April to October and another wet, from November to March. This study aims to characterize the rnicrobasin and evaluate the water quality from an ecological perspective. It is intended to correlate basic parameters of climatology, geology, morfometry and the land uses to the physical, chemical and biological characteristics of the water in the streams and reservoirs. Another objective was to characterize the planktonic communities in the three main reservoirs. The sampling were carried out monthly from September/1995 to September/1996 at 8 different stations in the rnicrobasin, including the reservoirs. At the reservoirs, sampling were made at the central point, at three different depths (surface, middle and bottom in the water column). The analysis of physical, chemical and biological characteristics of the water of the different streams indicated that there are no significant differences between the quality ofthe water ofthe Águas da Prata and Macuco streams. The São José stream, however, was quite different, since it is the one subjected to the heaviest aggression. Relatively high values of conductivity were observed at the locations most affected by animal wastes, although the highest values were registered for the São José stream, downstream from the point under the impact of the municipal landfill and leachate from the city of São Carlos. Among the nitrogen compounds, arnrnonium was the most abundant for the entire basin. Inorganic phosphate and total dissolved phosphorus concentrations were low, suggesting the adsorption of phosphorus by the sediment. The construction of dams on the Macuco stream created a discontinuity in the river system. A strong thermal stratification with anoxic hypolimnion was observed during the rainy period in all three studied reservoirs. There were no significant differences in nutrient concentration between samples taken in the dry and the wet seasons, except for the total phosphorus and reactive silicate. The mass balance for nutrients in the reservoirs indicated that the Igaraba reservo ir acts as a retention system, whereas the other two reservoirs act as exportation systems. The phytoplankton cornrnunity in the reservoirs was quantitatively dominated by Bacillariophyceae and Chlorophyta taxa, while the other groups were relatively rare. The zooplankton community was dominated by Rotifera throughout the study period. The development of the zooplankton as a whole was positively correlated to the development of phytoplankton. According to the trophic indices applied, the reservoirs can be classified as mesotrophic. It was observed that anthropogenic activities, particularly the inadequate use of soil for agriculture, cause erosion and the transportation of sediments to the water bodies. Agroindustrial businesses contribute to a higher concentration of materiaIs in runoff waters, causing waste accumulation in the streams and altering the quality of the water in a short distance from the springs.
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Ekosystemansatsen på landskapsnivåWalter, Martina January 2008 (has links)
<p>The Convention on Biological Diversity (CBD) promotes the Ecosystem Approach (EA). In this thesis it is analyzed how the EA approach could be applied to regional management of coastal areas in Sweden. The aim of this report is to compare management for preserving biodiversity on a landscape level in two regional coastal areas in Uppsala and Västra Götaland respectively. In Uppsala, one of the plans consists of a previous nature reserve and in Västra Götaland, a Regional landscape strategy has been established. The ecosystem approach is used as a theoretical framework in this thesis. More precisely, five EA operational guidelines have been used as analytical tools in the comparative approach adopted.</p><p>The results show that the Västra Götaland Regional landscape strategy has been most consistent with the EA framework, since it fulfills three of the five operational guidelines while Gårdsskärskusten only accomplish two of the criteria. The social aspects are more central in the landscape strategy than in Gårdskärskusten, which is the main difference between the two plans. One area of inadequacy detected in the landscape strategy was the few identified aspects on maintenance of landscape connectivity features. The Regional landscape strategy could, if established in every county in Sweden, be a way to prevent the loss of biodiversity. However the plan needs to be supported by actions where preservation and utilization are integrated in an economic context. By considering nature protection as a development opportunity in strategic planning rather than as only a cost, important steps towards a sustainable future can be taken.</p> / <p>För att implementera målsättningarna i FN:s Konvention om Biologisk Mångfald har en ekosystemansats (EA) antagits och en viktig ekosystemtyp i Sverige där EA kan appliceras är kuster. Syftet med examensarbetet är att, med ekosystemansatsen som analysverktyg, studera hur och varför två planer för att bevara biologisk mångfald på landskapsnivå i två regionala kustområden i Uppsala län respektive Västra Götalands län skiljer sig åt. Planen består i Uppsala län av ett tilltänkt naturreservat och i Västra Götalands län av en Regional landskapsstrategi. Uppsatsens teoretiska förankring sker i ekosystemansatsen, med fokus på dess fem vägledande punkter och metodvalet är en jämförande design. Inom ramen för den jämförande designen har sedan en innehållsanalys samt kompletterande semistrukturerade intervjuer utförts.</p><p>Resultatet visar att den Regionala landskapsstrategin i dagsläget är mer i linje med ekosystemansatsen, eftersom den uppfyller tre av fem vägledande punkter medan processen med Gårdsskärskusten enbart uppfyller två av fem vägledande punkter. I landskapsstrategin är sociala aspekter centrala och det är en förklaring till varför de olika planerna skiljer sig åt. Intressant är dock att betoningen på aktörsinvolvering verkar leda till att vissa ekologiska grundprinciper som konnektivitet i landskapet tonas ned, vilka är framträdande i processen med Gårdskärskusten. Regionala landskapsstrategier kan enligt min mening innebära ett stort steg mot att hindra förlusten av biologisk mångfald i Sverige om de uppförs i varje län. Inom landskapsstrategierna är det vidare essentiellt att skyddade områden, som exempelvis Gårdsskärskusten, också inkorporerar ett landskapsstrategitänk och i många fall innebär det att skötselåtgärder fortsätter att utföras. Svårigheten kan dock vara hur finansieringen av skötseln skall ske men där finns alternativa inkomstmöjligheter, från exempelvis naturturism och stresshantering på företag, som behöver utvecklas ytterligare.</p>
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Ekosystemansatsen på landskapsnivåWalter, Martina January 2008 (has links)
The Convention on Biological Diversity (CBD) promotes the Ecosystem Approach (EA). In this thesis it is analyzed how the EA approach could be applied to regional management of coastal areas in Sweden. The aim of this report is to compare management for preserving biodiversity on a landscape level in two regional coastal areas in Uppsala and Västra Götaland respectively. In Uppsala, one of the plans consists of a previous nature reserve and in Västra Götaland, a Regional landscape strategy has been established. The ecosystem approach is used as a theoretical framework in this thesis. More precisely, five EA operational guidelines have been used as analytical tools in the comparative approach adopted. The results show that the Västra Götaland Regional landscape strategy has been most consistent with the EA framework, since it fulfills three of the five operational guidelines while Gårdsskärskusten only accomplish two of the criteria. The social aspects are more central in the landscape strategy than in Gårdskärskusten, which is the main difference between the two plans. One area of inadequacy detected in the landscape strategy was the few identified aspects on maintenance of landscape connectivity features. The Regional landscape strategy could, if established in every county in Sweden, be a way to prevent the loss of biodiversity. However the plan needs to be supported by actions where preservation and utilization are integrated in an economic context. By considering nature protection as a development opportunity in strategic planning rather than as only a cost, important steps towards a sustainable future can be taken. / För att implementera målsättningarna i FN:s Konvention om Biologisk Mångfald har en ekosystemansats (EA) antagits och en viktig ekosystemtyp i Sverige där EA kan appliceras är kuster. Syftet med examensarbetet är att, med ekosystemansatsen som analysverktyg, studera hur och varför två planer för att bevara biologisk mångfald på landskapsnivå i två regionala kustområden i Uppsala län respektive Västra Götalands län skiljer sig åt. Planen består i Uppsala län av ett tilltänkt naturreservat och i Västra Götalands län av en Regional landskapsstrategi. Uppsatsens teoretiska förankring sker i ekosystemansatsen, med fokus på dess fem vägledande punkter och metodvalet är en jämförande design. Inom ramen för den jämförande designen har sedan en innehållsanalys samt kompletterande semistrukturerade intervjuer utförts. Resultatet visar att den Regionala landskapsstrategin i dagsläget är mer i linje med ekosystemansatsen, eftersom den uppfyller tre av fem vägledande punkter medan processen med Gårdsskärskusten enbart uppfyller två av fem vägledande punkter. I landskapsstrategin är sociala aspekter centrala och det är en förklaring till varför de olika planerna skiljer sig åt. Intressant är dock att betoningen på aktörsinvolvering verkar leda till att vissa ekologiska grundprinciper som konnektivitet i landskapet tonas ned, vilka är framträdande i processen med Gårdskärskusten. Regionala landskapsstrategier kan enligt min mening innebära ett stort steg mot att hindra förlusten av biologisk mångfald i Sverige om de uppförs i varje län. Inom landskapsstrategierna är det vidare essentiellt att skyddade områden, som exempelvis Gårdsskärskusten, också inkorporerar ett landskapsstrategitänk och i många fall innebär det att skötselåtgärder fortsätter att utföras. Svårigheten kan dock vara hur finansieringen av skötseln skall ske men där finns alternativa inkomstmöjligheter, från exempelvis naturturism och stresshantering på företag, som behöver utvecklas ytterligare.
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An Adaptive Ecosystem Approach to Rehabillitation and Management of the Cooum River Environmental System in Chennai, IndiaBunch, Martin January 2000 (has links)
This research investigates the application of an adaptive ecosystem approach to the problem of the Cooum River and environs in Chennai (formerly Madras), India. The Cooum River is an extremely polluted urban stream that flows into the Bay of Bengal through the heart of Chennai, India's fourth largest metropolis. During the dry (non-monsoon) season, the upper reaches of the river are dry and flow in the river may be attributed primarily to the production of sewage by the city's population. The river is essentially a foul-smelling open sewer.
Complexity of the problem is due as much to human factors (population growth, poverty, uncontrolled urban development, jurisdictional conflicts, modes of behaviour of the citizenry, and institutional culture) as to physical characteristics of the system (flat topography, tidal action, blockage of the river mouth by sand bar formation, and monsoon flooding). Uncertainty in the situation is both structural (regarding main processes and activities in the system and the nature of relationships among the various actors and elements), and parametric (having to do with scarcity, poor quality and restricted access to data).
This work has drawn upon methods and techniques of Adaptive Environmental Management and Soft Systems Methodology to operate the ecosystem approach and address the problem. Specifically, this has involved a series of workshops which have brought together planners, researchers, NGOs, and other stakeholders in a participatory process oriented toward problem definition, system identification and conceptualization, determination of objectives for management, and the generation and exploration of management interventions. In addition, a central component of the program has been the development of a loosely-coupled GIS, environmental simulation model, and a decision support module. This is based upon a framework provided by participants in the first workshop in the series, and operationalizes a common understanding of the system.
In addition to generating new insight into the nature of the problem situation, the research has provided a potentially useful tool to planners, managers and researchers in Chennai in the form of a GIS database and decision support system (DSS). Aside from the tool itself, it was found that the process of developing a conceptual model, and attempting to represent this in the DSS has made a significant contribution to understanding of the Cooum system. In particular, this process forced assumptions to be stated explicitly and publically, highlighted areas of uncertainty and led to new understanding in participants' conception of the problem situation. The program of research also provided a much needed forum for open debate and exchange of information which was removed from the restrictive institutional culture of government departments.
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An Adaptive Ecosystem Approach to Rehabillitation and Management of the Cooum River Environmental System in Chennai, IndiaBunch, Martin January 2000 (has links)
This research investigates the application of an adaptive ecosystem approach to the problem of the Cooum River and environs in Chennai (formerly Madras), India. The Cooum River is an extremely polluted urban stream that flows into the Bay of Bengal through the heart of Chennai, India's fourth largest metropolis. During the dry (non-monsoon) season, the upper reaches of the river are dry and flow in the river may be attributed primarily to the production of sewage by the city's population. The river is essentially a foul-smelling open sewer.
Complexity of the problem is due as much to human factors (population growth, poverty, uncontrolled urban development, jurisdictional conflicts, modes of behaviour of the citizenry, and institutional culture) as to physical characteristics of the system (flat topography, tidal action, blockage of the river mouth by sand bar formation, and monsoon flooding). Uncertainty in the situation is both structural (regarding main processes and activities in the system and the nature of relationships among the various actors and elements), and parametric (having to do with scarcity, poor quality and restricted access to data).
This work has drawn upon methods and techniques of Adaptive Environmental Management and Soft Systems Methodology to operate the ecosystem approach and address the problem. Specifically, this has involved a series of workshops which have brought together planners, researchers, NGOs, and other stakeholders in a participatory process oriented toward problem definition, system identification and conceptualization, determination of objectives for management, and the generation and exploration of management interventions. In addition, a central component of the program has been the development of a loosely-coupled GIS, environmental simulation model, and a decision support module. This is based upon a framework provided by participants in the first workshop in the series, and operationalizes a common understanding of the system.
In addition to generating new insight into the nature of the problem situation, the research has provided a potentially useful tool to planners, managers and researchers in Chennai in the form of a GIS database and decision support system (DSS). Aside from the tool itself, it was found that the process of developing a conceptual model, and attempting to represent this in the DSS has made a significant contribution to understanding of the Cooum system. In particular, this process forced assumptions to be stated explicitly and publically, highlighted areas of uncertainty and led to new understanding in participants' conception of the problem situation. The program of research also provided a much needed forum for open debate and exchange of information which was removed from the restrictive institutional culture of government departments.
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Environmental Processes, Social Perspectives and Economic Valuations of the CoastWilliams, Amy M. 2010 August 1900 (has links)
Coastal ecosystems provide important resources for social, economic and environmental capital to global and local communities. Socially, coastal ecosystems provide a place for people to recreate and get in touch with nature. Economically, tourism, fisheries, and businesses are dependent upon coastal resources. Environmentally, coasts provide habitat for diverse species of flora and fauna, and protection for watersheds and anthropogenic structures.
This research investigates three studies in order to provide information on social, economic and environmental issues in Matagorda, Texas. The first study uses LIDAR (Light Image Detection-and-Ranging) scanning, a remote sensing methodology that uses laser pulses to collect X, Y, and Z coordinates, to evaluate coastal changes after Hurricane Ike. Results suggest that landscape loss occurs immediately after the hurricane, but recovers and fluctuates throughout the year. Also, different areas of the dunes show unique changes during different times of the year.
The second study uses questionnaire surveys to collect demographic, social perspectives and opinions and economic information about coastal users on Matagorda Peninsula. The questionnaire investigates the most important characteristics to beach users, opinions and perceptions about beach safety, activities, maintenance and presence of seaweed, information about their trip, cost of their trip and demographics. The results provide broader knowledge about the beach users in Matagorda and indicate that while direct costs of using the beach are minimal, the indirect and intrinsic costs are much higher which result in a greater overall use value.
The third study investigates the use of the sargassum, a natural marine subsidy, as a fertilizer for dune plants. Beach raking provides a cleaner, more aesthetically pleasing experience for beach users but alters the natural design of the ecosystem by subsequently moving sand, nutrients, subsidies for habitat and fauna from the fore-beach to the dunes. Results show that sargassum does have potential as a natural fertilizer as it did not negatively affect any of the species. The results could be used to alter management practices in order to capitalize on this natural resource while still providing a clean sandy beach for recreationalists.
These three studies together provide ecological information about coastal functions and processes that can help in creating broad holistic science based management strategies.
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Aplicação da abordagem ecossistêmica ao estudo da microbacia do córrego São José (São Carlos - SP) / The ecosystem approach applied to the study of the São José stream basin (São Carlos - SP)Corina Verónica Sidagis Galli 30 January 1998 (has links)
As bacias hidrográficas são sistemas que fornecem um tipo de unidade adequada ao estudo dos ecossistemas e permitem um melhor entendimento científico dos processos naturais. Os estudos em pequenas bacias têm mostrado a dependência da composição das águas dos riachos das características dos ecossistemas terrestres adjacentes. A microbacia formada pelos córregos Águas da Prata, Macuco e São José está localizada a sudeste da cidade de São Carlos, Estado de São Paulo, com uma área de 13,9 Km2. O córrego Macuco apresenta vários represamentos, sendo os mais importantes os reservatórios Iguá, Igaraba e Iembó. Estes córregos apresentam pequena vazão e drenam solos ácidos. O solo da região é predominantemente argiloso e arenoso e a vegetação original é o cerrado. As áreas de campo antrópico estão ocupadas por culturas em geral e áreas de pastagem e criação animais. Quanto ao clima existem dois períodos: o seco e o chuvoso. O objetivo deste trabalho foi caracterizar e avaliar a qualidade da água do ponto de vista ecológico, determinar as interrelações entre os aspectos básicos da climatologia, geologia, morfometria, hidrologia e usos e ocupação do solo na microbacia hidrográfica com as variáveis físicas,químicas e biológicas das águas dos córregos e reservatórios, além de caracterizar as comunidades planctônicas dos reservatórios. Foram realizadas coletas mensais de 09/1995 a 09/1996 em 8 pontos da microbacia, sendo que três deles foram localizados nos reservatórios que foram analisados em três profundidades (superfície, meio e fundo da coluna de água). A análise das características físicas, químicas e biológicas da água dos córregos estudados indicou que não existem diferenças significativas entre os córregos Águas da Prata e Macuco. No entanto o córrego São José foi mais diferenciado, sendo este o que se mostrou mais impactado. As concentrações de oxigênio dissolvido foram baixas no córrego Macuco e no São José. Nos locais mais afetados pelos dejetos de animais foram observados altos valores de condutividade, embora os maiores valores tenham sido registrados no córrego São José, abaixo do trecho sob influência do chorume do aterro sanitário da cidade de São Carlos. Das formas de nitrogênio o amônio foi a mais abundante para toda a microbacia. As concentrações de fosfato inorgânico e fósforo total dissolvido foram baixas, indicando a provável absorção do fósforo pelo sedimento. A construção de barragens no córrego Macuco levou ao rompimento da continuidade do sistema do rio. Os três reservatórios apresentaram uma estratificação térmica acentuada durante o período de chuvas o que causou anoxia no hipolímnio. Não foram observadas diferenças significativas nas concentrações de nutrientes entre os períodos de chuva e seca, com exceção do fósforo total e o silicato reativo. O balanço de massa dos nutrientes nos reservatórios demonstrou que o reservatório Igaraba se comporta como um sistema de retenção de nutrientes enquanto os outros dois se comportam como sistemas de exportação. Nos reservatórios a comunidade fitoplanctônica foi dominada, em termos quantitativos, pelas Bacillariophyceae e pelas Chlorophyta, sendo os grupos restantes escassos. A comunidade zooplanctônica foi dominada numericamente pelos Rotifera durante todo o período de estudos. O desenvolvimento do zooplâncton como um todo correlacionou-se positivamente com o desenvolvimento do fitoplâncton. Segundo os índices de estado trófico utilizados os reservatórios se classificam como mesotróficos. Foi observado que as atividades antrópicas, especialmente o uso inadequado do solo para a agricultura, provocam erosão e carreamento de sedimentos para os corpos de água. As instalações agro-industriais contribuem para o aumento da concentração de materiais na água de escoamento, acumulando os resíduos nos riachos e alterando a qualidade da água próxima às nascentes. / Hydrographic basins provide an adequate subject for studies of ecosystems and a better understanding of natural processes. Studies of small basins revealed that the chernical composition of stream waters are strongly dependent upon the characteristics of the surrounding land ecosystems. The rnicrobasin formed by the Águas da Prata, Macuco and São José streams is located in the Southeast portion of the city of São Carlos, State of São Paulo, and covers an area of 13,9 Km2. The Macuco stream has several reservoirs, of which the Iguá, Igaraba and Iembó reservoirs are the most important ones. These streams have a low outflow volume and they run across acid soils. The soil is predominantly formed by silt and sand, and the original plant formation was the \"cerrado\", a savanna type of vegetation. The land through which these streams flow is cultivated with several different crops as well pastures for cattle. In regard to the climate, there are two different periods: one dry, lasting from April to October and another wet, from November to March. This study aims to characterize the rnicrobasin and evaluate the water quality from an ecological perspective. It is intended to correlate basic parameters of climatology, geology, morfometry and the land uses to the physical, chemical and biological characteristics of the water in the streams and reservoirs. Another objective was to characterize the planktonic communities in the three main reservoirs. The sampling were carried out monthly from September/1995 to September/1996 at 8 different stations in the rnicrobasin, including the reservoirs. At the reservoirs, sampling were made at the central point, at three different depths (surface, middle and bottom in the water column). The analysis of physical, chemical and biological characteristics of the water of the different streams indicated that there are no significant differences between the quality ofthe water ofthe Águas da Prata and Macuco streams. The São José stream, however, was quite different, since it is the one subjected to the heaviest aggression. Relatively high values of conductivity were observed at the locations most affected by animal wastes, although the highest values were registered for the São José stream, downstream from the point under the impact of the municipal landfill and leachate from the city of São Carlos. Among the nitrogen compounds, arnrnonium was the most abundant for the entire basin. Inorganic phosphate and total dissolved phosphorus concentrations were low, suggesting the adsorption of phosphorus by the sediment. The construction of dams on the Macuco stream created a discontinuity in the river system. A strong thermal stratification with anoxic hypolimnion was observed during the rainy period in all three studied reservoirs. There were no significant differences in nutrient concentration between samples taken in the dry and the wet seasons, except for the total phosphorus and reactive silicate. The mass balance for nutrients in the reservoirs indicated that the Igaraba reservo ir acts as a retention system, whereas the other two reservoirs act as exportation systems. The phytoplankton cornrnunity in the reservoirs was quantitatively dominated by Bacillariophyceae and Chlorophyta taxa, while the other groups were relatively rare. The zooplankton community was dominated by Rotifera throughout the study period. The development of the zooplankton as a whole was positively correlated to the development of phytoplankton. According to the trophic indices applied, the reservoirs can be classified as mesotrophic. It was observed that anthropogenic activities, particularly the inadequate use of soil for agriculture, cause erosion and the transportation of sediments to the water bodies. Agroindustrial businesses contribute to a higher concentration of materiaIs in runoff waters, causing waste accumulation in the streams and altering the quality of the water in a short distance from the springs.
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