• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 208
  • 135
  • 36
  • 9
  • 6
  • 4
  • 4
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 461
  • 461
  • 180
  • 174
  • 116
  • 115
  • 97
  • 91
  • 81
  • 55
  • 55
  • 43
  • 39
  • 38
  • 37
  • 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.
201

Análise da dinâmica hídrica nas unidades geológico-geomorfológicas quaternárias (UQ) da Bacia do Rio Guaratuba, Bertioga (SP) / Analysis of the dynamics of Quaternary Geomorphological-Geological units (UQs) in Guaratuba River Basin, Bertioga (SP)

Daniel dos Santos Pereira 19 January 2012 (has links)
Bertioga possui todos os tipos de Unidades Geológicas-Geomorfológicas Quaternárias (UQs) que podem ser encontradas no restante do litoral paulista, encaixados em uma planície costeira de pequenas dimensões. Tendo em vista a escassez de trabalhos que integrem os atributos hidrológicos da paisagem, o objetivo desta pesquisa foi analisar a dinâmica hídrica atmosférica, subterrânea e superficial da Bacia do Rio Guaratuba, tendo como viés a distribuição espacial das UQs, a partir de uma série de monitoramento de 24 meses, entre julho/2009 e agosto/2011. Para tanto foram analisados os seguintes componentes hídricos: (a) atmosféricos - por meio da análise das distribuições de pluviosidade, temperatura e umidade relativa do ar, para a caracterização do balanço hídrico climático (BHC) da bacia; (b) subterrâneos, a partir da variabilidade do nível do lençol freático; (c) superficial por meio da análise morfométrica das UQs. Os resultados foram tratados à luz de análises sinóticas dos sistemas atuantes no período de monitoramento e das séries históricas (décadas de 1960 a 1990) de pluviosidade e temperatura. Foi identificada uma tendência positiva na distribuição das chuvas, da praia para a baixa encosta da Serra do Mar, caracterizando assim o efeito orográfico. Chamou a atenção à ocorrência de invernos bastante úmidos em 2009 e 2010, ao contrário de 2011 e das tendências da série histórica. Neste sentido, não se pode descartar a possibilidade de influência de fenômenos de mesoescala, como o ENOS (El Niño e Oscilação Sul). Entre 2009 e meados de 2010 atuou o El Niño, sucedido pela La Niña, desde junho/2010 até o presente momento (início do decaimento em maio/2011, segundo dados do INPE). Os índices registrados se assemelham aos do ano de 1990, quando também ocorreu elevado volume de chuva durante o inverno e atuava um El Niño de forte intensidade. A temperatura e a umidade relativa do ar variaram de modo mais marcante entre áreas naturais e antropizadas, embora tenham se apresentado relativamente elevadas durante todo o período de monitoramento, quando comparadas às médias para a região. O BHC normal (série histórica) apresentou déficit hídrico apenas em agosto, com todos os outros meses caracterizando excedentes hídricos. Já o BHC sequencial (período de monitoramento) alternou-se entre excedentes hídricos elevados e meses de déficit hídrico, como ocorreu em abril e maio/2010 e maio e junho/2011. Portanto, entre essas duas séries parece ter havido uma migração do período seco, de agosto para abril/junho. Na planície costeira os níveis de lençol freático (NA) mais profundos ocorrem nas UQs mais antigas e de topografia mais elevada (terraços marinhos e fluviais pleistocênicos), localizados salvo quando há interferência local do horizonte B espódico, que regula a profundidade do (NA) e pode torná-lo temporariamente mais elevado ou mesmo suspenso. Os mais rasos (aflorantes e subaflorantes) estão nas paleodepressões estuarinas-lagunares holocênicas a atuais, localizadas na porção central da bacia. A oscilação vertical do NA ao longo do tempo apresentou correlação positiva com a variação mensal do BHC sequencial, mostrando que o sistema está em relativo equilíbrio. / Bertioga has all kinds of Quaternary Geomorphological-Geological units (UQs) that can be found in the rest of the coast paulista, embedded in a small coastal plain. Given the paucity of studies that incorporate the attributes of the hydrological landscape, the aim of this study was to analyze the dynamics of atmospheric water, groundwater and surfacewater of the Guaratuba River Basin, with the bias of the spatial distribution UQs from a series of 24 month-monitoring between July/2009 and August/2011. Therefore, were analyzed the following hydrological components: (a) atmospheric - by analyzing the distribution of rainfall, temperature and relative humidity, to characterize the climatic water balance (BHC) basin, (b) underground, from variability of groundwater level, (c) surface by means of morphometric analysis of UQs. The results were treated in the light of analysis of the synoptic systems operating in the rainfall and temperature monitoring period and the time series (the 1960s to 1990s). It was identified a positive trend in the rainfall distribution, from the beach to the low slope of Serra do Mar, characterizing the orographic effect. Attention has been drawn to the occurrence of very wet winters in 2009 and 2010, unlike 2011 and the historical series trends. In this sense, one cannot rule out the influence of mesoscale phenomena such as ENSO (El Niño and Southern Oscillation). Between 2009 and mid-2010 El Niño has happened, followed by La Niña, from June/2010 to the current date (beginning of the decay in May/2011, according to data from INPE). The rates are similar to those from the year 1990, when high rainfall also occurred during the winter and El Niño happened. The temperature and relative humidity ranged from a more marked way between natural and disturbed areas, although they have been performing relatively high throughout the monitoring period, compared to the averages for the region. The BHC normal (series) had only water deficit in August, with every other month featuring over water. Since the BHC sequential (monitoring period) alternated between high water surpluses and months of drought, as occurred in April and May/2010 and May and June/2011. Therefore a migration of the dry period from August to April/ June seems to have happened between these two series. The deeper coastal plain groundwater levels (NA) occur in oldest and with highest topography (Pleistocene marine terraces and river) UQs, located except when there is local spodic B horizon interference, which regulates the depth of the (NA) and can make it higher or temporarily suspended. The shallowest ones (outcrop and under outcrop) are in the lagoon-estuarine paleodepressions the current Holocene, located in the central portion of the basin. The vertical oscillation of the NA over time was positively correlated with the monthly variation of BHC sequence, showing that the system is in relative balance.
202

O ambiente fluvial das várzeas no espaço da metrópole: a bacia do Pirajuçara na metropolização de São Paulo / Environment of Inland Wetlands in the Metropolitan Area: Basin Pirajuçara in Metropolization of Sao Paulo

Silva, Marco Antonio Teixeira da 18 September 2009 (has links)
A Metrópole é um fenômeno em movimento. Seu processo, a metropolização, se constitui a partir de várias relações que envolvem a Natureza e a História. Esta pesquisa investiga a particularidade da apropriação do ambiente fluvial das várzeas da Bacia do Pirajuçara no processo de formação da metrópole de São Paulo. Historicamente, continuidades e descontinuidades se sucederam neste processo sob uma contradição fundamental: a afirmação da várzea como ambiente fluvial e a produção do espaço como sua negação. As intervenções nos rios e nas várzeas objetivam a metrópole sob as determinações formais do capital em geral. Tal condição cristaliza um papel muito particular deste ambiente na divisão do trabalho, fundamentalmente como espaços de circulação. Neste contexto, a relação entre a apropriação do ambiente fluvial das várzeas e a produção do espaço na metrópole se constitui numa problemática em que a catástrofe das inundações se põe como limite ao processo. A nova prática de retenção do escoamento nos reservatórios de contenção de cheias (piscinões) se objetiva nas ideologias do ambientalismo e da sustentabilidade. O que aparece como ruptura se apresenta como continuidade da apropriação das várzeas para a realização da metrópole como espaço de reprodução do valor. / The Metropolis is a phenomenon in movement. Its process, the metropolization consists of many relations involving nature and history. This research investigates the peculiar fluvial environment appropriation of the floodplains of the Pirajuçara River Basin during the formation of the metropolis of São Paulo. Historically, continuities and discontinuities have been succeeding each other in this process in a fundamental contradiction: the assertion of the floodplain as a river environment and the production of space as its negation. Interventions in rivers and wetlands in the city aim the metropolis under the formal determinations of capital in general. Such condition crystallizes a very particular role of this environment in labor division mainly as passage space. In this context, the relationship between the appropriation of the environment of river floodplains and the production of space in the metropolis composes a set of problems in which the disaster of flooding arises as the limit process. The new practice of restraining the flow with flood control reservoirs (piscinões) has its objectives in environmentalism and sustainability ideologies. What appears as disruption shows up as continuity of floodplains appropriation in order to carry out the metropolis as an area for value reproduction.
203

Modelo de procedimentos para elaboração de metodologia de valoração econômica de impactos ambientais em bacia hidrográfica - estudo de caso - Guarapiranga - aplicação da função dose-resposta. / Model procedures for drafting methodology economic valuation of environmental impacts in river basin - case study - Guarapiranga - application of the dose-response function.

Silva, Maria Hercília da 06 December 2007 (has links)
Este trabalho apresenta a análise dos resultados obtidos, através de pesquisa bibliográfica, sobre o uso dos recursos hídricos na Bacia Hidrográfica do Guarapiranga na Região Metropolitana de São Paulo, cujo uso prioritário é o Abastecimento Público. Identifica os impactos decorrentes tanto pela ocupação desordenada, quanto pela sobreposição de outros usos incompatíveis com a manutenção de sua qualidade e quantidade, existentes em diagnósticos realizados, no intuito de avaliar as distorções na valoração econômica dos danos ambientais. Para valoração desses impactos foi adotada a metodologia da produtividade marginal, onde o papel do recurso ambiental no processo produtivo é representado por uma função dose-resposta, que relaciona o nível de provisão do recurso ambiental (água bruta) ao de produção respectiva do produto no mercado (água tratada). A aplicação desta função permite a mensuração do impacto no sistema produtivo, dada uma variação marginal na provisão do bem ou serviço ambiental, e a partir desta variação, pode - se estimar o valor econômico de uso do recurso ambiental. / This paper presents the analysis of the results obtained by means of bibliographic research on the use of water resources in the Guarapiranga River Basin in the metropolitan region of São Paulo, whose use is the priority Utilities. It identifies the impacts caused by the occupation both disorderly, as the overlapping of the other uses incompatible with the maintenance of their quality and quantity, existing in diagnoses made, in order to assess the distortions in the economic valuation of environmental damage. For valuation of these impacts was adopted the methodology of marginal productivity, where the role of the environmental resource in the production process is represented by a dose-response function, which relates the level of provision of the environmental resource (water gross) to the production of their product on the market (treated water). The application of this function allows the measurement of impact on the production system, given a marginal variation in the provision of environmental goods or services, and from this change, one can estimate the economic value of resource usage environment.
204

Análise da dinâmica hídrica nas unidades geológico-geomorfológicas quaternárias (UQ) da Bacia do Rio Guaratuba, Bertioga (SP) / Analysis of the dynamics of Quaternary Geomorphological-Geological units (UQs) in Guaratuba River Basin, Bertioga (SP)

Pereira, Daniel dos Santos 19 January 2012 (has links)
Bertioga possui todos os tipos de Unidades Geológicas-Geomorfológicas Quaternárias (UQs) que podem ser encontradas no restante do litoral paulista, encaixados em uma planície costeira de pequenas dimensões. Tendo em vista a escassez de trabalhos que integrem os atributos hidrológicos da paisagem, o objetivo desta pesquisa foi analisar a dinâmica hídrica atmosférica, subterrânea e superficial da Bacia do Rio Guaratuba, tendo como viés a distribuição espacial das UQs, a partir de uma série de monitoramento de 24 meses, entre julho/2009 e agosto/2011. Para tanto foram analisados os seguintes componentes hídricos: (a) atmosféricos - por meio da análise das distribuições de pluviosidade, temperatura e umidade relativa do ar, para a caracterização do balanço hídrico climático (BHC) da bacia; (b) subterrâneos, a partir da variabilidade do nível do lençol freático; (c) superficial por meio da análise morfométrica das UQs. Os resultados foram tratados à luz de análises sinóticas dos sistemas atuantes no período de monitoramento e das séries históricas (décadas de 1960 a 1990) de pluviosidade e temperatura. Foi identificada uma tendência positiva na distribuição das chuvas, da praia para a baixa encosta da Serra do Mar, caracterizando assim o efeito orográfico. Chamou a atenção à ocorrência de invernos bastante úmidos em 2009 e 2010, ao contrário de 2011 e das tendências da série histórica. Neste sentido, não se pode descartar a possibilidade de influência de fenômenos de mesoescala, como o ENOS (El Niño e Oscilação Sul). Entre 2009 e meados de 2010 atuou o El Niño, sucedido pela La Niña, desde junho/2010 até o presente momento (início do decaimento em maio/2011, segundo dados do INPE). Os índices registrados se assemelham aos do ano de 1990, quando também ocorreu elevado volume de chuva durante o inverno e atuava um El Niño de forte intensidade. A temperatura e a umidade relativa do ar variaram de modo mais marcante entre áreas naturais e antropizadas, embora tenham se apresentado relativamente elevadas durante todo o período de monitoramento, quando comparadas às médias para a região. O BHC normal (série histórica) apresentou déficit hídrico apenas em agosto, com todos os outros meses caracterizando excedentes hídricos. Já o BHC sequencial (período de monitoramento) alternou-se entre excedentes hídricos elevados e meses de déficit hídrico, como ocorreu em abril e maio/2010 e maio e junho/2011. Portanto, entre essas duas séries parece ter havido uma migração do período seco, de agosto para abril/junho. Na planície costeira os níveis de lençol freático (NA) mais profundos ocorrem nas UQs mais antigas e de topografia mais elevada (terraços marinhos e fluviais pleistocênicos), localizados salvo quando há interferência local do horizonte B espódico, que regula a profundidade do (NA) e pode torná-lo temporariamente mais elevado ou mesmo suspenso. Os mais rasos (aflorantes e subaflorantes) estão nas paleodepressões estuarinas-lagunares holocênicas a atuais, localizadas na porção central da bacia. A oscilação vertical do NA ao longo do tempo apresentou correlação positiva com a variação mensal do BHC sequencial, mostrando que o sistema está em relativo equilíbrio. / Bertioga has all kinds of Quaternary Geomorphological-Geological units (UQs) that can be found in the rest of the coast paulista, embedded in a small coastal plain. Given the paucity of studies that incorporate the attributes of the hydrological landscape, the aim of this study was to analyze the dynamics of atmospheric water, groundwater and surfacewater of the Guaratuba River Basin, with the bias of the spatial distribution UQs from a series of 24 month-monitoring between July/2009 and August/2011. Therefore, were analyzed the following hydrological components: (a) atmospheric - by analyzing the distribution of rainfall, temperature and relative humidity, to characterize the climatic water balance (BHC) basin, (b) underground, from variability of groundwater level, (c) surface by means of morphometric analysis of UQs. The results were treated in the light of analysis of the synoptic systems operating in the rainfall and temperature monitoring period and the time series (the 1960s to 1990s). It was identified a positive trend in the rainfall distribution, from the beach to the low slope of Serra do Mar, characterizing the orographic effect. Attention has been drawn to the occurrence of very wet winters in 2009 and 2010, unlike 2011 and the historical series trends. In this sense, one cannot rule out the influence of mesoscale phenomena such as ENSO (El Niño and Southern Oscillation). Between 2009 and mid-2010 El Niño has happened, followed by La Niña, from June/2010 to the current date (beginning of the decay in May/2011, according to data from INPE). The rates are similar to those from the year 1990, when high rainfall also occurred during the winter and El Niño happened. The temperature and relative humidity ranged from a more marked way between natural and disturbed areas, although they have been performing relatively high throughout the monitoring period, compared to the averages for the region. The BHC normal (series) had only water deficit in August, with every other month featuring over water. Since the BHC sequential (monitoring period) alternated between high water surpluses and months of drought, as occurred in April and May/2010 and May and June/2011. Therefore a migration of the dry period from August to April/ June seems to have happened between these two series. The deeper coastal plain groundwater levels (NA) occur in oldest and with highest topography (Pleistocene marine terraces and river) UQs, located except when there is local spodic B horizon interference, which regulates the depth of the (NA) and can make it higher or temporarily suspended. The shallowest ones (outcrop and under outcrop) are in the lagoon-estuarine paleodepressions the current Holocene, located in the central portion of the basin. The vertical oscillation of the NA over time was positively correlated with the monthly variation of BHC sequence, showing that the system is in relative balance.
205

Modelling the Effects of Deforestation on Stream Flows in Arror River Basin-Kenya

Muli, Cosmus January 2007 (has links)
<p>Abstract.</p><p>Like other developing countries, forest conversion to agricultural land has been a common practice in Kenya for the last four decades. Apart from illegal logging, the main cause is the growing population. For most developing countries where majority rely on agriculture for food production, conversion of forests into agricultural land is likely to occur. Kenya is one among such countries and is where the study basin is located. Knowledge of hydrological studies is crucial for proper planning and decision making of limited water resources in river basins. Even in regions where data is limited, changes in land use is a concern to many basin communities over the globe including Arror inhabitants since it has an impact on stream flows. Despite Arror downstream communities’ claims on reducing river flows, scientific proof on this is lacking. Such kind of belief/claim can result to conflicts (Downstream vs. Upstream water users). The main objective of this thesis was therefore to determine the effect of land use changes on Arror basin hydrology, focusing on the impact of deforestation since it has been the main land use change for the last four decades. The overall intention of the study is to verify the downstream basin’s inhabitant’s hypothetical thinking and also create an information foundation base for other future studies in the basin. Based on the lessons learned in this study, several recommendations have been highlighted, including land satellite rainfall data to augment the rainfall data obtained from the relatively sparse rain gauge network in the basin.</p>
206

A Comparative Ecological Study of Two Sister Species of Darters in Kentucky, <i>Etheostoma Kantuckeense</i> and <i>Etheostoma Lawrencei</i>

Schmidt, Bjorn Victor 01 May 2009 (has links)
Etheostoma kantuckeense and E. lawrencei are former members of the wide ranging E. spectabile species complex. Etheostoma kantuckeense is endemic to the Barren River Basin in Southern Kentucky and Northern Tennessee, while E. lawrencei occurs in the Green River, Salt River, and Cumberland River Basins of Central and Eastern Kentucky. Isolation of populations within these drainages has allowed for a relatively recent evolutionary divergence, leading to slight differences in morphology. This study was conducted to address if geographical isolation has led to measurable differences in the ecology of these two species. In particular, habitat preference across three spatial scales and growth rates were examined. To assess stream preference within a drainage, 59 streams were sampled for fish abundance and environmental parameters in the Upper Barren River Basin (E. kantuckeense; N=24) and the Upper Green River Basin (E. lawrencei; N=35). Channel unit preference and growth rates were compared in two physically similar upland streams, which were sampled monthly from August 2007 through August 2008. Surveys for microhabitat preference were conducted in these same streams in November 2008. Results from a canonical correspondence analysis show that both species occupy equivalent stream types in their respective watersheds. Within the two survey streams, run habitat was preferred over riffle and pool habitats over the course of the year, and both species exhibited similar seasonal habitat shifts. Microhabitat associations for both species were predominately for small to coarse gravel (1–40mm diameter) substrates. In addition, growth of individuals in their first year of life was similar for both species. These results suggest that these species maintain similar ecological traits in their respective watersheds. The retention of these headwater adapted traits in disjunct populations likely promoted vicariant allopatric speciation in these fishes through isolation and the inability to disperse across ecological barriers.
207

Artificial Recharge Of Groundwater In Kucuk Menderes River Basin, Turkey

Peksezer, Ayse 01 March 2010 (has links) (PDF)
K&uuml / &ccedil / &uuml / k Menderes River Basin located in western Turkey has been facing continuous groundwater level decreases for the past 30 years. In dry periods, irrigation demand is completely met by pumping from groundwater system, which reduces water levels significantly. This provides enough storage to be recharged in wet seasons when streams are running. However, increased runoff in wet season are not utilized neither for irrigation nor for recharge and lost to the Aegean Sea without being infiltrated. Hence, surface artificial recharge methods can be useful to collect excess water in recharge basins, thus allowing infiltration to increase groundwater storage in wet seasons to be later utilized in dry seasons. A 2-D groundwater model is set up by using SEEP/W software. The material functions and parameters used in the model for saturated/ unsaturated conditions are taken from previous studies. Calibration was done to check the accuracy of input data and to control the validity of model. The amount of excess water that will be collected in recharge basins was estimated from flood frequency analysis. Concerning different probabilities, different scenarios were simulated to observe the increase in groundwater levels. Simulation results suggest that significant increase in groundwater storage could be achieved by applying artificial recharge methods. In addition to recharge basins, to reinforce the effect of artificial recharge, simulations were repeated with the addition of an underground dam at downstream side of the basin. Simulation results indicate that the increase in groundwater storage is not sufficient to warrant construction of the underground dam.
208

Integrierte Bewirtschaftungsplanung für Flussgebiets- und Hochwasserrisikomanagement

Wendler, Wiebke 23 September 2009 (has links) (PDF)
Die Dissertation befasst sich mit der integrierten Bewirtschaftungsplanung von Flusseinzugsgebieten. Die europäische Wasserrahmenrichtlinie (WRRL, 2000/60/EG) und die europäische Hochwasserrichtlinie (HWRL, 2007/60/EG) setzen dafür neue Maßstäbe, indem beide die Mitgliedsstaaten zur Aufstellung einzugsgebietsbezogener Planungsinstrumente verpflichten. In der Arbeit werden eingangs die wesentlichen Prozesse, theoretischen Modelle und Ansatzpunkte für ein integriertes Management von Flusseinzugsgebieten vorgestellt. Die Anforderungen an Bewirtschaftungspläne und Maßnahmenprogramme der WRRL werden den Vorgaben für die Erstellung der Hochwasserrisikomanagementpläne und ihren planerischen Grundlagen gemäß HWRL gegenübergestellt. Potenzielle Synergien und Konflikte zwischen den Zielen und Maßnahmen werden identifiziert. Der Vergleich der Planungsschritte und -methoden zeigt, dass Abstimmungsbedarf zwischen den Planungsinstrumenten des Flussgebiets- und Hochwasserrisikomanagements für sämtliche Planungsschritte besteht, von der Systemanalyse bis zur Maßnahmenumsetzung. Darauf aufbauend wird ein Konzept für eine integrierte Bewirtschaftungsplanung entwickelt. Das Konzept besteht aus einzelnen fachlich-methodischen Planungsmodulen für jeden Planungsschritt. Sie können im Zusammenhang oder für sich genommen zur Abstimmung zwischen den Plänen des Flussgebiets- und Hochwasserrisikomanagements dienen. Abschließend werden die fachlichen und organisatorischinstitutionellen Potenziale des Konzepts diskutiert und weitergehender Forschungsbedarf aufgezeigt. / The thesis addresses the integrated planning of river basins. For this, the European Water Framework Directive (WFD, 2000/60/EC) and the Floods Directive (FD, 2007/60/EC) are setting new benchmarks by committing its member states to set up river basin-wide management plans. At the beginning of the thesis, the most important processes, theoretical models and options of intervention for integrated river basin management are introduced. The requirements for the river basin management plans and the programmes of measures of the WFD will be contrasted with the specifications for the flood risk management plans according to the FD and their fundamental planning documents. Potential synergies and conflicts between the objectives and measures are identified. The comparison of the planning steps and methods show that all planning steps, from the systems analysis to the implementation of measures, require a coordination of the planning instruments of river basin management and flood risk management. Based on these findings, a concept of integrated river basin management planning is developed. The concept is composed of planning modules for each planning step. For the reconciliation between the plans of river basin management and flood risk management, those planning modules can be used in combination or separately. Finally, the technical and institutional potentials of the concept are discussed. Need for further research is identified.
209

Addressing water availability and climate change issues in the Cordillera Blanca, Peru through technical analysis and community building strategies

Read, Laura K. 14 February 2011 (has links)
Accelerated tropical glacial melt on the order of 15-18 meters per year since the 1980's in Peru's Cordillera Blanca region is alarming rural communities and urban authorities, causing them to seek technical support for risk management and adaptation actions. Melting glaciers coupled with changing seasonal rainfall patterns has left many rural communities in the upper Rio Santa basin lacking sufficient fresh water supply to support livestock, irrigation and human consumption. In response to these concerns, a Water Evaluation And Planning (WEAP) model was created by the Stockholm Environmental Institute for simulating glacial melt and flow in the Santa River. Through input parameters of climate, glacial runoff, water use, crop acreage, soil type and groundwater interactions, WEAP has the flexibility to model scenarios for different operation schemes. These schemes allow users to determine the most effective ways to regulate their resources and explore adaptation actions (e.g. altering farming practices and building reservoirs) for future planning. This project improved the existing model by including observed water demand data for irrigation, and evaluating the Climate Forecast System Reanalysis (CFSR) dataset to serve as a potential source for filling gaps in the historic climate record. These improvements added robustness to the model and correlated well with historic stream flow at La Balsa (R² = 0.78 , Nash = 0.68). Two scenarios were explored where (1) a 50% reduction in potato crop was replaced with maize for each sub-basin, and (2) a 10% reduction in precipitation was applied over the upper basin. Results show that the WEAP model is sensitive to changes in crop type and rainfall at the sub-basin scale, an encouraging finding for future exploration. This investigation enables communities to base future decisions on technical evidence and provides a basis for educating citizens on the importance of evaluating their available resources under climate change projections / text
210

Hydrologic modeling of the Pecos River basin below Red Bluff Reservoir

Yalcinkaya, Sedat 17 June 2011 (has links)
The segment of the Pecos River that extends from Red Bluff Reservoir until it discharges to the Rio Grande/Bravo near Langtry was studied in this project. Hydrologic behavior of the basin was analyzed between 1981 and 2000, the first ten year period for calibration and the second ten year period for validation by using Water Evaluation and Planning Software (WEAP, SEI, 2006). Simulated streamflows were compared with naturalized streamflows (RJBCO, 2003) at two control points, one in the middle of the basin near Girvin and the other one is at the end of the basin near Langtry. The purpose of the project is to create a valid model for water availability simulations in the Pecos River Basin to be used for future water availability simulations considering climate change effects. The basin was divided into two parts in order to evaluate the results, the upper basin and the entire basin (below Red Bluff reservoir) according to the location of control gages. Simulated streamflows closely match the naturalized flows at the Girvin station in the upper basin. Although the results at the Langtry station for the entire basin are not as good as Girvin, the model still reproduces streamflows well enough to represent the hydrologic behavior of the basin, especially for the base flow. Considering the complex geological structure of the Pecos River Basin below Red Bluff Reservoir, the results can be considered satisfactory. The model can be used for future water availability predictions in the basin considering climate change effects. / text

Page generated in 0.0511 seconds