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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.
331

Challenges in modelling hydrological responses to impacts and interactions of land use and climate change.

Warburton, Michele Lynn. January 2012 (has links)
To meet society’s needs for water, food, fuel and fibre the natural land cover throughout the world has been extensively altered. These alterations have impacted on hydrological responses and thus on available water resources, as the hydrological responses of a catchment are dependent upon, and sensitive to, changes in the land use. Similarly, changes in the climate through enhanced carbon dioxide (CO2) levels in the atmosphere have resulted in increased temperature and altered precipitation patterns that alter hydrological responses. In combination, land use change and global climate change form a complex and interactive system, whereby both human influences and climate change manipulate land use patterns, and changes in land uses feed back to influence the climate system, with both impacting on hydrological responses. Relatively few studies have been undertaken examining the combined impacts of climate change and land use change on water resources, with no consensus emerging as yet as to combined influence of land use change and climate change on hydrological responses and the role of geographical characteristics in determining the overriding influence. There is, however, agreement that the effect on hydrological responses will be amplified. Given that South Africa is currently water stressed and considered to be highly exposed to climate change impacts, an understanding of hydrological responses to the complex interactions between land use and climate change is crucial to allow for improved integration of land use planning in conjunction with climate change adaptation into water resources management. To determine the sensitivity of land use to changing climate, a sensitivity study assessing the potential impacts of climate change on the areas climatically suitable for key plantation forestry species was undertaken. Under sensitivity scenarios of climate change the climatically optimum areas for specific forest species were shown to shift, with optimum areas changing in extent and location between and within South Africa’s provinces. With potential for shifts in land use due to climate change shown, the imperative to improve understanding of the dynamics between land use and climate change as well as the subsequent impacts on hydrological responses was further established. For the assessment of climate-land use-water interactions, a process-based hydrological model, sensitive to land use and climate, and changes thereof, viz. the daily time step ACRU model was selected. In order to increase the confidence in results from the model in a study such as this, its representation of reality was confirmed by comparing simulated streamflow output against observations across a range of climatic conditions and land uses. This comparison was undertaken in the three diverse South African catchments chosen for the study, viz. the semi-arid, sub-tropical Luvuvhu catchment in the north of the country, which has a large proportion of subsistence agriculture and informal residential areas, the Upper Breede catchment in the winter rainfall regions of the south, where the primary land uses are commercial orchards and vineyards, and the sub-humid Mgeni catchment along the eastern seaboard, where plantation forestry is dominant in the upper reaches, commercial plantation sugarcane and urban areas in the middle reaches, and urban areas dominate the lower reaches. Thus, in effect a space for time study was undertaken, thereby reducing the uncertainty of the model’s ability to cope with the projected future climate scenarios. Overall the ACRU model was able to represent the high, low and total flows, and thus it was concluded that the model could be used with confidence to simulate the streamflows of the three selected catchments and was able to represent the hydrological responses from the range of climates and diversity of land uses present within the catchments. With the suitability of the model established for the theme of this research, the understanding of the complex interactions between hydrological responses and land use could be improved. The hydrological responses of the three selected catchments to land use change were varied. Results showed that the location of specific land uses within a catchment plays an important role in the response of the streamflow of the catchment to that land use change. Furthermore, it was shown that the contributions of different land uses to the streamflow generated from a catchment are not proportional to the relative area of those land uses, and the relative contribution of the land use to the catchment streamflow varies with the annual rainfall of the catchment. With an improved understanding of the dynamics between land uses and hydrological responses, the impacts of climate change on hydrological responses were assessed prior to analysing the combined impacts on land use and climate change. Five plausible climate projections from three coupled atmosphere-ocean global climate models covering three SRES emissions scenarios which were downscaled with the RCA3 regional climate model and adjusted using the distribution-based scaling (DBS) approach for bias correction were used as climate input to the ACRU model, with future projections applied to a baseline land cover scenario compared to historical climate applied to the same baseline land cover scenario. No consistent direction of change in the streamflow responses was evident in the Mgeni and Luvuvhu catchments. However, decreases in streamflow responses were evident for all five scenarios for the Upper Breede. With an understanding of the separate impacts of land use and climate change on hydrological responses, an analysis of the combined impacts was undertaken to determine which changes were projected to be of greater importance in different geographical locations. Results indicated that the drier the climate becomes, the relatively more significant the role of land use becomes, as its impact becomes relatively greater. The impacts of combined land use and climate change on the catchments’ streamflow responses varied across both the temporal and spatial scales, with the nature of the land use and the magnitude of the projected climate change having significant impacts on the streamflow responses. From the research undertaken, the key results were • that the climatic variable to which plantation forestry species are most sensitive is rainfall; • that optimum growth areas for plantation forestry are projected to shift under changing climates, having a potentially significant impact on the landscape and thus on the hydrological responses from the landscape; • that the daily time-step, physical-conceptual and process-based ACRU model is appropriate for use in land use change and climatic change impact studies as shown through a space for time study; • that the contributions of different land uses to the streamflow generated from a catchment is not proportional to the relative area of that land use and that, as the mean annual precipitation of a subcatchment decreases, so the disparities between the relative areas a land use occupies and its contribution to catchment streamflow increases; • that specific land use changes have a greater impact on different components of the hydrological response of a catchment; • that land uses which currently have significant impacts on catchment water resources will place proportionally greater impacts on the catchment’s water resources if the climate were to become drier; thus the drier the climate becomes, the more relatively significant the role of land use becomes; • that when considering any hydrological impacts of land use change, climate change or combined land use and climate change, assessments need to consider the scale where the localized impacts may be evident, the progression of the impacts as the streamflow cascades through the catchment, as well as the impacts at the whole catchment scale where the accumulation of the effects through the catchment are evident; and lastly • that each catchment is unique with its own complexities, feed forwards and feedbacks, thus each catchment will have a unique threshold as to where land use change or climate change begins to have a significant influence of the hydrological response. Given these complex interactions between land use, climate and water, there is a growing imperative to improve the understanding of the movement of water within catchments, to be receptive and adaptive to new concepts and information, and to developing resilient and adaptive water management strategies for the future in a way that minimises the risks and maximises the benefits to potential impacts of climate change. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
332

Towards the development of a multi-criteria decision support system for selecting stormwater best management practices.

Duncan, Peter Neil. January 2001 (has links)
The aim of this dissertation was to develop a multi-criteria decision support system (MCDSS) to allow a specified manager to select with confidence one or many of these BMPs for a particular site. The principal design approach was a review of South African and international literature pertaining to stormwater management techniques, in particular BMPs. This information was formulated into a primary matrix using a rank-and-weighting method. The scores were then checked against the literature to ensure that they were reasonable, culminating in the initial MCDSS. The MCDSS was then provided with seven scenarios, described in the literature, and the output reviewed. Although, the MCDSS would select appropriately when given few criteria for selection when these were increased, inappropriate outcomes resulted. Consequently, weighting factors were assigned to each criterion. The MCDSS was further tested using all the selection criteria and the output deemed satisfactory. The MCDSS was then tested in a case study of the Town Bush stream catchment at eleven sites along the river network and the results were adequate. Taking into consideration the economic aspects of BMP implementation a need also arose for the sites to be allocated to certain authorities depending upon ownership or responsibility. The sites were prioritised depending on potential threat to property and lastly by the hydrological nature of the stream at each site. A stormwater plan for the study area was also proposed. Although the MCDSS was functioning adequately it was not without its limitations. Limitations included the use of drainage areas as a surrogate measure for peak discharge thus, not allowing the user to design a series of BMPs or treatment chain. A second limitation was that initially the BMPs were designed as offline systems where stormwater is managed before entering the channel but in this study they were used as inline systems. Hence the ultimate selection was biased towards those BMPs able to deal with large drainage areas. Recommendations for further improvement include the development of a surrogate measure for drainage area thus allowing the user to design a treatment chain of BMPs; testing the MCDSS in more diverse circumstances; developing a more comprehensive set of selection criteria; and developing a clearer priority-setting model as the one used was rather simplistic. In conclusion the MCDSS provides the user with a useful tool where the selection and implementation of BMPs no longer has to take place in an ad hoc manner. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2001
333

Recommendations for best management practices in the Juday Creek corridor : mitigating golf course development impact on brown trout habitat

Wilczynski, Martha O. January 1996 (has links)
Juday Creek, in St. Joseph County, Indiana, has been designated a salmonid stream due to its reproducing population of brown trout (Salmo trutta). Increasing development in the watershed in recent years has been accompanied by deterioration of the stream habitat. The purpose of this project is to analyze a proposed golf course project and develop a set of recommendations for best management practices (BMP's) which will mitigate the effects of the golf course on the trout habitat of Juday Creek.Site features were inventoried, and the design program was formulated to include aesthetics, playability, impact to fisheries and wildlife, and groundwater quality. Current stormwater best management practices were assessed for their applicability to this project. Additionally, cultural best management practices currently utilized in the golf course industry were reviewed. BMP recommendations include: 1. Use of temporary erosion control practices during construction to avoid sedimentation of the stream.2. Use of Integrated Pest Management including selection of low maintenance grass species.3. Use of vegetated swales to filter and divert golf course runoff to out-of-play areas for further filtering.4. Use of vegetated storm filter/infiltration/wetland retention areas as stormwater filters in out- of-play areas.5. Supplemental tree planting along the stream corridor to provide additional shading of the stream.6. Restoration of structure such as logs, boulders, and cobble in the stream to improve fish habitat. / Department of Landscape Architecture
334

An ecological pilgrimage: fostering ecological literacy in the Lake Winnipeg watershed

Stankewich, Shawn 13 January 2014 (has links)
This practicum investigates the application of ecological literacy theory to the practice of landscape architecture. Ecological literacy can be defined as the ability to comprehend the complex relationships of one’s surrounding environment and live life with greater environmental sensitivity. The Lake Winnipeg watershed is home to over 5 million people, and draws its water from four Canadian provinces and four American states. With the anthropogenic manipulation of the landscape, native watershed functions like water retention and filtration have been compromised. Each year, increasing amounts of phosphorus enter the lake from agricultural and urban fertilisers and effluents. This nutrient loading creates algal blooms toxic to humans and other species that rely on the lake for survival. The proposed programmatic framework and design interventions are intended to address these impacts by fostering watershed sustainability and ecological literacy, while engaging citizens in the processes associated with increasing local ecological integrity.
335

森林施業の実態に基づいた森林基盤設備に関する研究

中澤, 昌彦, NAKAZAWA, Masahiko 12 1900 (has links)
農林水産研究情報センターで作成したPDFファイルを使用している。
336

Water resources, efficiency pricing, and revenue recycling

Pitafi, Basharat A. K January 2004 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 111-120). / Also available by subscription via World Wide Web / xii, 120 leaves, bound ill. 29 cm
337

A Comparative Analysis of State-Level Watershed Management Frameworks in the Pacific Northwest

Erickson, Adam Michael, 1979- 09 1900 (has links)
xiii, 236 p. : ill. (some col.) / Over the past two decades, contemporary state-level watershed management burgeoned in the Pacific Northwest. This research offers a comparative analysis of contemporary state-level watershed management frameworks in the Pacific Northwest. The four case study areas consist of Idaho, Oregon, Washington, and Northern California. This study begins with a historical analysis of the greater watershed movement in natural resource management. Next, document analysis and key informant interviews are utilized to detail the watershed management framework of each state. Finally, this study explores a comparative analysis of each state framework. Results indicate that while the case study areas share many characteristics endemic to the bioregion, the watershed management framework of each state differs substantially. Key informant interviews indicate that these differences often reflect the unique sociopolitical climate of each state. Results additionally indicate the vital importance of stable state-derived funding for the establishment and resilience of watershed management organizations. / Committee in charge: Dr. Michael Hibbard, Chairperson; Dr. Richard Margerum, Member; Dr. Max Nielsen-Pincus, Member
338

Águas superficiais na bacia do Ribeirão Água Parada no município de Bauru-SP : potencial de utilização para o abastecimento público /

Gomes, Luciene. January 2012 (has links)
Orientador: Jorge Hamada / Banca: Edson Aparecido Abdul Nour / Banca: Isabel Cristina de Barros Trannin / Resumo: A estreita relação entre o uso e a ocupação do solo e qualidade da água é destacada numa bacia hidrográfica periurbana no município de Bauru, Estado de São Paulo, Brasil. Cerca de 70% do abastecimento municipal se dá através do aquífero Guarani, que se encontra regionalmente no limite de sua exploração sustentável e o município tem como única alternativa, em seus limites administrativos, o manancial superficial estudado. O estudo abrangeu a identificação de fontes poluentes, o monitoramento mensal de oitos pontos de amostragem e a elaboração de um modelo de qualidade da água. Fontes pontuais de poluição predominan na região da cabeceira da bacia hidrográfica, pela contribuição de esgoto doméstico advindos de áreas urbanizadas, com indústrias e complexos penitenciários (CP). Fontes difusas predominam no médio e no final do percurso da drenagem principal devido às atividades agropastoris. O modelo de Streeter-Phelps, ajustado para o corpo principal, apresentou boa correlação até o médio percurso, onde as amostragens foram mais detalhadas. Apesar da forte pressão urbana, o Índice de Qualidade da Água (IQA) indica, águas de boa qualidade para abastecimento público. Contudo, os limites dessa qualidade podem ser facilmente extrapolados uma vez que os vetores de crescimento urbano apontam para esta bacia. Este fator demonstra a importância do monitoramento contínuo e a aplicação do modelo de qualidade de água como instrumentos para o desenvolvimento de planos efetivos de gestão desse recurso hídrico / Abstract: This study covers the use and occupation and their influence on water quality in a watershed in a periurban in Bauru city, State of Sao Paulo, Brazil. About 70% of the municipal supply is through the Guarani aquifer, which is regionally within the limits of their sustainable exploitation and the municipality has the only alternative, in their administrative boundaries, the source surface studied. The study includes the identification of sources if pollutants, the montly monitoring at eight sampling stations and water quality modeling. Point sources of pollution prevalent in the region of the head of the basin, the contribution of sewage coming from urban areas, with industries and prison complex (PC). Diffuse sources dominate the middle and at the very end the main drain due to agropastoral activities. The Streeter-Phelps model, adjusted for the main body, showed a good correlation to the middle path, where the samples were more detailed. Despite the strong urban pressure, the Water Quality Index (AQI) also indicates good quality water for public supply. However, this quality limits can be easily extrapoled since the vectors of urban point to the basin. This factor shows the importance of continuous monitoring and implementation of water quality model as tools to develop effective plants to manage this water resource / Mestre
339

Geração da série histórica de vazão por meio do modelo SMAP: subsídio para o plano de manejo da bacia do Rio Grande de Ubatuba. / Generating streamflow records through the smap model: a contribution for the elaboration of the management plan for the Rio Grande watershed, Ubatuba.

Viviane Coelho Buchianeri 13 April 2004 (has links)
A bacia hidrográfica do Rio Grande de Ubatuba (26Km2) encontra-se quase que totalmente recoberta com vegetação nativa da Mata Atlântica, e grande parte está inserida no interior do Parque Estadual da Serra do Mar. O Rio Grande é um manancial estratégico para o município, pois abastece 88% da população, que recebe água tratada de serviço público. Com o propósito de conhecer a potencialidade hídrica do manancial de forma a subsidiar tecnicamente a elaboração do Plano de Manejo para a bacia, o presente estudo foi conduzido para gerar a série histórica de vazão, usando o Modelo SMAP (Soil Moisture Accounting Procedure) e analisar o balanço entre a disponibilidade e a demanda de água. Com apenas quatro anos incompletos de dados fluviométricos e com a série histórica de 67 anos de dados de precipitação, foi possível calibrar os parâmetros e validar o modelo com uma correlação de 0,838 entre as vazões estimada e observada e por último gerar a serie histórica de vazão. Com a série histórica de vazão gerada foi feita a análise temporal do balanço entre a disponibilidade e demanda que permitiram identificar a insuficiência hídrica para atender a demanda para abastecimento público ou para manutenção dos processos ecológicos do manancial, considerando três aspectos: a flutuação da população, a ocorrência de anos hídricos secos e, mesmo nos anos hídricos normais, ocorrência de períodos de meses secos prolongados. Com base na análise conjunta dos resultados, algumas ações consideradas compatíveis para a prevenção de possível escassez de água no futuro foram formuladas, visando proporcionar melhor qualidade de vida à população. / The Rio Grande Watershed of Ubatuba (26km2 ) is almost completely covered with native Atlantic Rainforest vegetation, and a large part is within the bounds of the Serra do Mar State Park. The Rio Grande is a strategic water source for the municipality, supplying 88% of the population demand with treated water via a public service. In order to analyse the water potential of the source and to acquire technical information for the preparation of the Watershed Management Plan, this study was carried generate streamflow historic data, using the SMAP (Soil Moisture Accounting Procedure) model. This, in turn, permitted to analyse the balance between demand and availability of water.With only 4 years of incomplete streamflow data and 67 years of rainfall data, it was possible to calibrate the parameters and validate the model with a correlation of 0.838 between the estimated and observed flows, and finally produce a streamflow history.To produce the streamflow history, a time analysis was carried out with the balance between availability and demand, which allowed the identification of water shortages for public supply, as well as for the maintenance of the stream ecological processes, considering the following three aspects: population fluctuations, the occurrence of drought years and, even in normal years, the occurrence of extended periods of drought.
340

Proposição preliminar de indicadores como instrumento de manejo integrado da microbacia hidrográfica do Ribeirão da Cachoeirinha e do Córrego do Meio, no bairro de Catuçaba, São Luiz do Paraitinga, SP / Preliminary Proposal of Indicators as an Integrated Management Instrument of Cachoeirinha and Córrego do Meio Creek Watersheds, Catuçaba District, São Luiz do Paraitinga, SP

Roxane Lopes de Mello 24 June 2009 (has links)
Os problemas modernos são complexos e requerem soluções que reflitam impactos nos aspectos sócio-econômicos, ambientais e político-institucionais em termos dos diferentes graus de importância atribuídos a eles. Dentro deste contexto, um paralelo acerca de conceitos relativos ao desenvolvimento sustentável, agricultura sustentável, bacias hidrográfica, microbacias hidrográficas bem como o uso de indicadores para medir a sustentabilidade local é de suma importância no âmbito do desenvolvimento local sustentável. O trabalho tem como objetivo coletar dados relacionados com as práticas de gestão territorial e de desenvolvimento rural nas microbacias do Ribeirão Cachoeirinha e Córrego do Meio no município de São Luiz do Paraitinga, SP. E a partir das análises desses dados propor indicadores de sustentabilidade preliminares voltados para a gestão integrada das duas microbacias e a promoção do desenvolvimento sustentável na comunidade local. Os indicadores devem ter como base a sustentabilidade das atividades da microbacia, e também ser ferramentas úteis para operacionalizar o desenvolvimento sustentável e servir de referência no processo decisório. Os procedimentos metodológicos para a caracterização geral da área e da comunidade envolvidas foram os levantamentos de campo e de fontes documentais. A definição dos critérios para a delimitação da área baseou-se nos limites da microbacia propostos pelo Programa Estadual de Microbacias Hidrográficas, desenvolvido pelo Governo do Estado de São Paulo através da Secretaria de Agricultura e Abastecimento. Os resultados levaram ao desenvolvimento de 83 indicadores de sustentabilidade bem como a necessidade de articulação dos setores da região para adoção de estratégias que busquem realmente o desenvolvimento sustentável local. / The modern problems are complex and require solutions that reflect impacts on socioeconomic, environmental, and political-institutional aspects in terms of their different degrees of importance. Within this context, a crosscutting analysis of concepts related to sustainable development, sustainable agriculture, watershed structure, and the use of indicators to measure local sustainability is of paramount importance for determining the type of local level development. The objective of this research is to collect information related to management practices and rural development in the context of the watersheds of Ribeirão Cachoeirinha and Córrego do Meio in the municipality of São Luiz do Paraitinga, SP. The goal is to propose preliminary sustainability indicators that would support an integrated watershed management strategy and promote a sustainable development of the community. Indicators should be based on the sustainability of all activities developed in the watershed and also be useful tools for implementing the actual sustainable development and serve as reference in the decision making process. Methods involved a general characterization of the area and the community through field survey and document sources. The criteria utilized for defining the boundaries of the area were based on the Watershed State Program developed by the State Government of São Paulo through the Department of Agriculture and Supply. The results led to the development of 83 sustainability indicators and a must needed articulate strategy by the community sector in the region to promote true local sustainable development.

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