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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.
31

Optimal Utilization of Playa Lake Water in Irrigation

Dvoracek, M. J., Roefs, T. G. 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / Playa lakes usually occur in arid or semiarid regions where lands are flat and there is an absence of well-developed surface drainage nets. They are usually filled by surface runoff from highly erratic precipitation patterns. There are about 20,000 of them in the high plains of Texas and their volume of storage is an estimated 2.5-3 maf. As such, they represent a major underutilized water source. The major drawbacks to their utilization are high evaporation losses, questionable depth-area relations and the stochastic nature of the rainfall source. This paper assumes that the water is available and presents a dynamic programming model useful in determining the optimal utilization of the water for irrigation. If irrigation is the major use, its timing of application is of paramount importance. A deterministic dynamic programming model, utilizing the state variables of antecedent soil moisture and amount of available water, is presented, and provides the time and amount of irrigation required to maximize crop response. A better stochastic model is also presented which considers rainfall probability and resulting lake filling. The models are only first attempts and do not incorporate all possible variables.
32

A Bibliographic Information System for Water Yield Improvement Practices

White, Linda M. 20 April 1974 (has links)
From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / Effects of vegetation management on water and other renewable natural resources and amenities are subjects of a computerized reference retrieval information system operated out of the department of watershed management, university of Arizona. Although WaMIS (watershed management information system is a subsystem of the arid lands information system, it has its own unique scope. The system, which serves as a link between bibliographic material and users who need access to the information, provides a personalized bibliography for the user in his area of interest. Documents identified as relevant to the system's scope are abstracted and indexed, and references stored in a computer bank. In response to specific inquiries from users, the computer tapes are searched under indexing terms, author, and/or data, and a printout of citations (giving author, data, title, source, abstract, and indexing terms) relevant to the inquiry is sent to the user.
33

Ephemeral Flow and Water Quality Problems: A Case Study of the San Pedro River in Southeastern Arizona

Keith, S. J. 15 April 1978 (has links)
From the Proceedings of the 1978 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 14-15, 1978, Flagstaff, Arizona / Discontinuous water quality data for the San Pedro River in southeastern Arizona is analyzed to illustrate the nature of water quality problems of ephemeral flow. The San Pedro drains a northerly-trending basin of 4,483 square miles, of which 696 are in Mexico and 3,787 in Arizona. Several questions arise in the consideration of a rational management plan: what is the necessity for protection of ephemeral flow quality when the channel consists of a dry wash much of the year, where there is little aquatic or wildlife to protect, and where occasional flow during flood conditions is put to little use by humans; and where and how do we use the ephemeral flow it is indeed decided to utilize it. Such questions as these form the basis of this discussion in an effort to bring out the point that water quality problems of ephemeral flow in arid areas differ from those in the humid zone. It is argued that in between the extremes of prohibiting or treating all runoff or eliminating all sources of pollution, there is actually little that can be done to control all sources of pollution in this typical arid stream, despite the fact that standards, for the most part unattainable, have been set for this flow.
34

Viabilidade da implantação de um programa de pagamentos por serviços ambientais: uma análise na sub-bacia do Pirajibu, Sorocaba-SP / Implementation viability of payments for environmental services program: an anlysis in the Pirajibu watershed, Sorocaba - SP

Corrêa, Carina Júlia Pensa 20 April 2016 (has links)
Submitted by Milena Rubi (milenarubi@ufscar.br) on 2017-08-08T19:13:45Z No. of bitstreams: 1 CORREA_Carina_2016.pdf: 35718212 bytes, checksum: 67e15c2afd55ade670a7eb98e27ea9a6 (MD5) / Approved for entry into archive by Milena Rubi (milenarubi@ufscar.br) on 2017-08-08T19:13:55Z (GMT) No. of bitstreams: 1 CORREA_Carina_2016.pdf: 35718212 bytes, checksum: 67e15c2afd55ade670a7eb98e27ea9a6 (MD5) / Approved for entry into archive by Milena Rubi (milenarubi@ufscar.br) on 2017-08-08T19:14:02Z (GMT) No. of bitstreams: 1 CORREA_Carina_2016.pdf: 35718212 bytes, checksum: 67e15c2afd55ade670a7eb98e27ea9a6 (MD5) / Made available in DSpace on 2017-08-08T19:14:09Z (GMT). No. of bitstreams: 1 CORREA_Carina_2016.pdf: 35718212 bytes, checksum: 67e15c2afd55ade670a7eb98e27ea9a6 (MD5) Previous issue date: 2016-04-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Public policy incentives are essential to the effectiveness of environmental law and the preservation of services provided by ecosystems. In this context, Payments for Ecosystem Services –PSE programs remunerate environmental services providers through funds built from the user/polluter pays logic. This study aimed to evaluate the possibility of implementing a PSA program in Pirajibu watershed, Sorocaba -SP, and suggest suitable alternatives for the conservation of water resources in the region. To this end, secondary data were collected on public agencies. In addition, were analyzed pictures from the RapidEye satellite (Ministry of Environment-ME), and with the help of satellite images from Google Earth, processed in Quantum GIS 1.6 software- Open Source Information Systems Finally, field trips were made to verify the information found. The results indicate that there is difficulty identifying possible providers and calculate the opportunity cost of the land, since agriculture is a rare activity in the region. Regarding environmental services, there was a great potential of the Pirajibu –Mirim River for water supply. This watershed has been studied in more detail, its water sources were mapped and some of them diagnosed in macroscopic analysis in the field. The water sources are, for the most part, in particular areas, with water having satisfactory aspects. However, there is the presence of garbage, lack of identification, proximity roads and the lack of environmental compliance expected by the Brazilian Forest Code (Lei nº. 12.651/ 2012). This scenario shows the importance that public policy in Sorocaba-SP considers the recovery and protection of water sources, however, not directly compensating the owner. It is suggested that the model has the forecast works for soil conversation on dirt roads, in addition to a donation of inputs and technical assistance to owners interested in recovery. Also considering the characteristics of relief and zoning of the master plan, it is proposed to establish a Private Reserve of National Heritage - PRNP at the head region of Pirajibu -Mirim River. Finally, it is suggested the implementation of other tax incentive policies in the region, such as property tax reduction in suitable properties with economic and social use. / As políticas públicas de incentivo são imprescindíveis para a efetividade das legislações ambientais e para a conservação dos serviços providos pelos ecossistemas. Nesse contexto, programas de Pagamentos por Serviços Ambientais-PSA remuneram provedores de serviços ambientais por meio de fundos construídos a partir da lógica do usuário/poluidor-pagador. O presente trabalho objetivou avaliar a possibilidade da implantação de um programa de PSA na sub-bacia do Pirajibu, no município de Sorocaba-SP, bem como sugerir alternativas adequadas para a conservação dos recursos hídricos na região. Para tanto, foram realizadas coletas de dados secundários em órgãos públicos. Além disso, foram analisadas imagens do satélite Rapideye (Ministério do Meio Ambiente-MMA), e, com o auxílio de imagens de satélite do programa Google Earth, processadas no programa Quantum GIS 1.6. Por fim, saídas de campo foram realizadas para verificação das informações encontradas. A análise dos resultados encontrados indica a dificuldade na identificação de possíveis provedores e nos cálculos do custo de oportunidade da terra, já que a agricultura é uma atividade rara na região. Em relação aos serviços ambientais, a microbacia do rio Pirajibu-Mirim apresentou grande potencial para abastecimento hídrico. Adotada como área prioritária, suas nascentes foram mapeadas e algumas delas diagnosticadas em análise macroscópica em campo. As nascentes estão, em sua grande maioria, localizadas em áreas particulares, com água apresentando aspectos satisfatórios. No entanto, observa-se a presença de lixo, ausência de identificação, proximidade de estradas de terra e a ausência de adequação ambiental prevista pelo Código Florestal brasileiro (Lei nº 12.651/2012). Esse cenário mostra a importância de que uma política pública de conservação em Sorocaba considere a recuperação e proteção de nascentes, entretanto, não remunerando diretamente o proprietário. Sugere-se que o modelo tenha como previsão obras para conservação do solo em estradas de terra, além da doação de insumos e assistência técnica aos proprietários interessados na recuperação. Considerando também as características do relevo e o zoneamento do plano diretor, propõe-se a instituição de uma Unidade de Conservação que incorpore a região de cabeceira do rio Pirajibu-Mirim. Por fim, sugere-se a implantação de outras políticas de incentivos fiscais na região, como redução de IPTU em propriedades adequadas ambientalmente e que apresentem uso econômico e social.
35

Vývoj osídlení v mikroregionu Zarabag (jižní Uzbekistán) na základě archeologických pramenů / Dynamics of the settlement pattern in the microregion of Zarabag (southern Uzbekistan) on the basis of archaeological sources

Augustinová, Anna January 2017 (has links)
15 Abstract The following thesis summarizes results of the archaeological research in the microregion of the Zarabag Oasis in the South Uzbekistan. The non-destructive research focused on the collection and evaluation of the archaeological data that allow to reconstruct the settlement dynamics in the oasis during the ages. Previously, there was not archaeological evidence available in the region. The fieldwork in the oasis and its closest surroundings was conducted by way of extensive surface survey (global coverage of the oasis focused on the detection of archaeological evidence), and intensive one (systematic surface survey on a closely defined area). The extensive survey proved to be more suitable for the studied environment in terms of the quality and quantity of the collected archaeological data. One part of the survey consisted in detection of the water sources (springs, surface canals and even remains of the karez systems). The basic units of extensive survey were represented by polygons (gardens, fields, cemeteries, tepas etc.), to which the finds collected during the research were attributed. Their dating in the combination with their spatial distribution allowed then to reconstruct the settlement processes and dynamics in the microregion of the oasis. One part of the research deals also with the...
36

Mikropolutanty ve zdrojích vod a možnosti jejich odstranění / Micropollutants in water resources and ways of their elimination

Lukášová, Daniela January 2018 (has links)
The diploma thesis deals with micro-fuels in drinking water sources and their subsequent removal. In the thesis mainly pesticides and pharmaceuticals are described. The reader is first introduced to the most common pesticides occurring in water and their consumption. Drugs are described in a similar context. In addition, there are practical studies on the occurrence, degradation and removal of micro-pollutants from water. The final thesis is a laboratory experiment dealing with the removal of salicylic acid from water by filtration through the filtration material Bayoxide E33 and activated carbon. The thesis describes the procedure and results of the experiment.
37

Ancient Greek water management : the case of Northern Greece

Vieira, Shelby 08 1900 (has links)
L’eau est une ressource essentielle pour nourrir les hommes, les animaux, et les plantes. Par contre, les eaux stagnantes peuvent attirer vermine et maladies, et les fortes pluies provoquer des inondations soudaines. Malgré son caractère essentiel, l’archéologie de la gestion de l’eau dans le nord de la Grèce est souvent limitée à quelques paragraphes inscrit dans des études plus vastes, à l’exception de quelques article s comme « Sanitation and Wastewater and Stormwater Management in the Ancient Kingdom of Macedonia » de E. Kaiafa . Ainsi, ce mémoire a pour objectif d’examiner la manière dont les Grecs ont relevé le défi de l’approvisionnement de leurs villes en eau potable et de l’évacuation des eaux usées et impures, aux périodes archaïque, classique et hellénistique. Ce mémoire s’articule en quatre chapitres afin de fournir une analyse descriptive détaillée des différentes facettes de la gestion de l’eau. Après une introduction générale, nous nous pencherons d’abord sur l’attitude des Grecs anciens envers l’eau et sur leur conception d’une source d’eau fraîche. S’ensuivront un survol des condition géographiques en Grèce du Nord ainsi qu’une discussion sur la manière dont celles ci peuvent affecter l’étude des systèmes d’eau de la Grèce antique. Les trois autres chapitres se concentreront sur l’étude des vestiges et archives archéologiques de diverses villes du nord de la Grèce, comme Argilos, Pella, et Thasos. Premièrement, les structures artificielles construites pour récolter les sources d’eau douce seront étudiées. S’ensuivra un chapitre s’attardant à la question de la relation entre la gestion de l’eau, la topographie de la ville, et le drainage urbain et domestique. Finalement, une section portant sur l’évacuation des eaux dans les fortifications du nord de la Grèce conclura cette étude. / Water is an essential resource for nourishing people, animals, and plants. At the same time, stagnant waters attract vermin and disease, and heavy rainfall causes flash floods. The archeology of water management in Northern Greece is often regulated to a few paragraphs in a broader context, except for articles such as E. Kaiafa’s on “Sanitation and Wastewater and Stormwater Management in the Ancient Kingdom of Macedonia.” This thesis explores how the Greeks handled the challenges of sustaining their cities with water and ridding themselves of used and impure waters in the Archaic, Classical and Hellenistic periods. This dissertation is separated into four main chapters in order to provide a descriptive analysis of what pertains to water management. After a general introduction, the first topic of interest outlines the ancient Greek attitudes toward water and their view of a portable water source. To complement this, there is also a discussion on the geographical conditions of northern Greece and how that affects the study of ancient Greek water systems. The other three chapters study the archeological record from various cities all over northern Greece, such as Argilos, Pella, and Thasos. The first of those chapters discusses what manmade structures were constructed to harvest freshwater sources. Following this is a study on the connectivity of water management, the city's topography, and urban and domestic drainage. A section on the water evacuates found on northern Greek fortifications concludes the study.
38

The utilisation of satellite images for the detection of elephant induced vegetation change patterns

Simms, Chenay 02 1900 (has links)
South Africa’s growing elephant populations are concentrated in relatively small enclosed protected areas resulting in the over utilisation of the available food sources. Elephants and other herbivores as well as other natural disturbances such as fires and droughts play an important role in maintaining savannah environments. When these disturbances become too concentrated in a particular area the vegetation composition may be negatively affected. Excessive damage to the vegetation would result from exceeding the capacity of a protected area to provide food resources. The effect of the 120 elephants on the vegetation of Welgevonden Private Game Reserve, is not known. The rugged terrain of this reserve makes it a difficult, time consuming and labour intensive exercise to conduct ground studies. Satellite images can be used as a monitoring tool for vegetation change and improve the quantity and quality of environmental data to be collected significantly, allowing more informed management decision-making. This study evaluated the use of satellite imagery for monitoring elephant induced vegetation change on Welgevonden Private Game Reserve. The LANDSAT Thematic Mapper multispectral images, acquired at two yearly intervals from 1993 until 2007 were used. However, no suitable images were available for the years 1997, 2001 and 2003. A series of vegetation change maps was produced and the distribution of water sources and fire occurrences mapped. The areas of change were then correlated with the spatial distribution of water points and fire occurances, with uncorrelated areas of change. This was analysed using large animal population trends, weather data and management practices. On the visual comparison of the vegetation maps, it was seen that over this time period there was some decrease and thinning of woodland, but the most notable change was the increase of open woodland and decrease in grasslands. Using only the digital change detection for the period 1993 to 2007, a general increase in vegetation cover is seen. But this generalisation is misleading, since comparing the digital change detection to the vegetation maps indicates that while vegetation cover may have increased, significant changes occurred in the vegetation types. Most of the areas of significant change that were identified showed a strong positive correlation with burnt areas. The distribution of the water sources could not be directly linked to the vegetation change although rainfall fluctuations seemed to have accelerated vegetation changes. Years with high game counts, such as 1999, also coincide with very low rainfall making it difficult to differentiate between the effects of heavy utilisation of vegetation and low rainfall. Furthermore, many of the initial vegetation changes could be the result of land use changes due to the introduction of browsers, selective grazers and elephants that allow for more natural utilisation of the vegetation. Remote sensing makes it possible to successfully track changes in vegetation and identify areas of potential elephant induced vegetation change. Vegetation changes caused by disturbances, such as fire and anthropogenic activities, can be accounted for but it is not possible to conclude with a high level of certainty that the further changes seen are solely a result of elephant damage. Further work is required to reliably isolate elephant induced vegetation changes, as well as to establish the effects these changes have on the ecosystem as a whole. / Environmental Sciences / (M. Sc. (Environmetal Sciences))
39

Právní režim chráněných území a ochranných pásem v ochraně vod / Legal regime of protected areas and protective zones by the water protection

Zíbrt, Daniel January 2016 (has links)
84 ABSTRACT This thesis is concerned on the topic "Legal regime of protected areas and protective zones by the water protection." Water like environmental compartment has a key role to the existence of life on Earth. That is the reason for its protection. For achieving this protection could not be protected only this environmental compartment, but it is necessary to focus on other ones, which are related to this protection. The main aim of this thesis is to analyse the situation and the ways of ensuring the territorial water protection, to point out the basic types of them and their similar and different characteristics and provide a comprehensive explication of territorial water protection. For these reasons, the thesis is divided into two parts. The first is dealing with systematization of water protection and water protection relationship as a whole and territorial water protection as one of its important elements. This part is necessary for the orientation and the issue of inclusion territorial water protection to the entire system of water protection. The second part of this thesis at first reflects on the ways of promulgation of types of the territorial water protection and then is directly focused on them. The first type of territorial water protection represents the protected area of natural water...
40

Estrada Parque: estrat?gia de desenvolvimento sustent?vel, o caso da estrada parque na serra da Cantareira / Parkway: strategy of sustainable development, the case of Cantareira Mountain Parkway

Conde, Carlos Alberto dos Reis 19 February 2008 (has links)
Made available in DSpace on 2016-04-04T18:21:43Z (GMT). No. of bitstreams: 1 Carlos Alberto dos Reis Conde1.pdf: 8834910 bytes, checksum: 76d61d59d66eb7b65fa9743bea40865d (MD5) Previous issue date: 2008-02-19 / This dissertation is about conflicts between the natural environment and the urbanization process, and the possibilities of a sustainable development strategy on an area around a road placed on Cantareira Mountain range in Sao Paulo state. This road gets a special landscape and environment interest, mainly by local and regional economy, water production system that supplies the Sao Paulo metropolitan region and its protection. It presents studies of roads cases with special landscape and environment concerns in the world and in Brazil name or not Parkway. It shows and discusses the Cantareira/Roseira Parkway project in Mairipor?, development by local environment entities. It deepens the future of the project face the planning and metropolitan and local management, as well as, public sectors and private interests. The critical analysis of this experience will contribute to a new approach to fore-see similar ecosystems and regions and the adequacy of implementation tools and management of these strategies. / A disserta??o trata dos conflitos entre o meio natural e a ocupa??o urbana e as possibilidades de uma estrat?gia de desenvolvimento sustent?vel para o entorno de uma estrada localizada na Serra da Cantareira, SP. H? nela especial interesse paisag?stico e ambiental sobretudo em fun??o dos valores da economia local, regional e de produ??o e prote??o de ?guas para abastecimento da regi?o metropolitana de S?o Paulo. Apresenta estudos de casos como esse no Brasil e no mundo, que usam ou n?o o nome de Estrada Parque. Exp?e e discute o projeto da Estrada Parque Cantareira/Roseira em Mairipor?, desenvolvido por entidades ambientalistas locais. Aprofunda o destino do projeto face os limites do planejamento e gest?o metropolitanos e locais, bem como os interesses p?blicos, setoriais e privados. A avalia??o cr?tica dessa experi?ncia dever? contribuir para um novo olhar ?s regi?es de biomas semelhantes e para a adequa??o dos instrumentos de implanta??o e gest?o dessa estrat?gia.

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