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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Improving Water Use in the Landscape Through Subsurface Drip Irrigation

Zedick, Daniel January 2016 (has links)
Sustainable Built Environments Senior Capstone Project / This paper examines Subsurface Drip Irrigation(SDI) as a solution to water conservation in landscape irrigation. This is a problem because of the drought that the southwestern United States is experiencing, and the amount of water that landscapes utilize and which is ultimately wasted due to inefficient practices. Subsurface drip irrigation represents a potential solution due to its high efficiency and water saving ability; however, there are some problems within it as a system. Utilizing a multiple case studies approach, this paper looked at three of the top irrigation companies, Rain Bird, Toro, and Netafim, and examined how they innovated to overcome the problems with SDI. Synthesizing the best and most effective practices from each company, a model for improving SDI was generated.
2

Women and work in irrigated landscapes in rural India

Girard-Zdanowska, A. M. January 2014 (has links)
In India, the 1992 Reservation Law and the 2006 Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA) have formalised women as legitimate actors in rural development. These gender-inclusive policies do not necessarily conform to the traditional domestic role of women, which often precludes them from formally engaging in political processes and labour outside the home. In Northern India, these major policy shifts are illustrated in ancient irrigation management systems. With growing rural outmigration and climatic variability aggravating water resources and food security issues, irrigation management is increasingly dependent on the active participation of women. Yet irrigation management is still widely perceived as a male responsibility. This thesis investigates how women adapt and respond to new institutionally mandated responsibilities and expectations as female leaders and as water users. The research is presented in four complementary papers based on quantitative and qualitative data collected during fieldwork in Delhi and Himachal Pradesh. Three major findings emerged to contribute to theories and evidence of the role of public policies in shaping gendered outcomes for common pool resource management in irrigation system in India. First, gender norms affect women differently depending on their public role in the community. Unlike non-political women, female leaders, as public figures, must secure communal approbation to gain power, credibility, and socio-economic networks. As a result, female leaders shape their political behaviour and policy preferences around local notions of femininity, female morality, and labour-based ideas of expertise. Second, for female water users, gender inclusive policies that legitimise their role as participants in formal political processes and the labour force for irrigation management increase their likelihood to defy gender-based restrictions and engage in formal political processes around irrigation management. Third, providing that formal/legal structures legitimize their actions, women will readily breach gender norms if they are to economically benefit from it. The implication of this research are that policies aimed at providing legal support for women to engage in formal rural development, combined with formalised economic opportunities for women are effective eroding agents of gendered institutions and are catalysts in facilitating the engagement of women in all areas of rural development. Given worldwide concerns over rural development, this study encourages such governmental actions to enable the effective and full engagement of future generations of women in the formal management of common pool resources.
3

Evaluation of soil carbon stocks in response to management changes in sugarcane production / Avaliação do estoque de carbono do solo devido à mudança de manejo no sistema de produção da cana de açúcar

Zani, Caio Fernandes 15 May 2015 (has links)
Brazilian commodities, such as ethanol, are looking for sustainable production to suit the international market demands. An important parameter for assessing sustainability is the carbon (C) footprint calculation of the product. Thus, studies of the variations in soil C stocks on the ethanol production are essential. Studies in relation to land use change are already been developed; however information about parameters of management changes on the sugarcane production is needed. The aim of this research was to evaluate the soil C stock in response to two main management changes in sugarcane production: i) no vinasse to vinasse application (NV-V), ii) burned to unburned harvesting system (B-UB). We also evaluated soil C stock changes in a chronosequence irrigation practices (native vegetation (NV), sugarcane irrigated 4 years (I4) and 6 years (I6), a new management in semi-arid and drought regions in Brazil which also aims high yields. Modelling approaches in order to assess long-term effects were also analysed. The NV-V transition showed higher soil C stock for V regime for topsoil layers 0-40 cm depth mainly due to the addition of organic compounds to the soil. Vinasse can also enhance biomass production and crop yield. The B-UB transition showed higher soil C stock in the UB regime from 20 to 60 cm depth due to higher organic matter accumulation from the maintenance of the straw to the field. The cumulative soil C stock for 1 metre depth had an increase of 1.1 and 0.75 Mg C ha-1 y-1 in the NV-V and B-UB transitions, respectively. From modelling was observed that V and UB sites had an increase of soil C stock by 2150, being a difference of 2.8 and 23 Mg ha-1 in the equilibrium state between NV-V and B-UB regimes, respectively. In the irrigation practices, the I4 showed higher soil C stock than NV in the 20 to 40 cm; while I6 was lower than NV in the 50 to 100 cm depth. Simulated long-term analyses showed increase of topsoil C stock of 12 and 13 Mg ha-1 for I6 and I4 area, respectively, compared to NV on 2100. The results in this study are pioneers in relation to soil C stock studies in the management transitions and irrigation practices. This information may be used as a basis for public policies decision which dealing of the land use and global warming / Commodities brasileiras, como o etanol, estão à procura de uma produção sustentável para atender às exigências do mercado internacional. Um parâmetro importante para avaliar a sustentabilidade é o cálculo da pegada de carbono (C) do produto. Assim, os estudos sobre as variações nos estoques de carbono do solo (ECS) sobre a produção de etanol são essenciais. Estudos em relação à mudança no uso da terra já estão sendo desenvolvidos; no entanto informações sobre parâmetros de mudanças de manejo na produção de cana de açúcar são necessárias. O objetivo desta pesquisa foi avaliar o ECS em resposta a duas principais mudanças de manejo: i) não vinhaça para aplicação de vinhaça (NV-V), ii) sistema queimado para não queimado (B-UB). Mudanças de ECS também foram avaliadas em sistemas de irrigação em cronoseqüência: vegetação nativa (NV), cana de açúcar irrigada por 4 anos (I4) e por 6 anos (I6). Modelagem matemática para avaliar o efeito a longo prazo também foi analisada. A transição NV-V apresentou maior ECS para o regime V em 40 cm de profundidade, devido principalmente à adição de compostos orgânicos ao solo. A vinhaça também pode aumentar a produção de biomassa e rendimento da cultura. A transição B-UB apresentou maior ECS no regime UB em 20-60 cm de profundidade devido ao acúmulo de matéria orgânica a partir da manutenção da palha no campo. O ECS acumulado para 1 metro de profundidade obteve um aumento de 1,1 e 0,75 Mg C ha-1 y-1 nas transições NV-V e B-UB, respectivamente. A partir de modelagem foi observado que os regimes V e UB obteve um aumento de ECS em 2150, sendo uma diferença de 2,8 e 23 Mg ha-1 no estado de equilíbrio para os regimes NV-V e B-UB, respectivamente. Nas práticas de irrigação, o I4 foi superior ao NV nos 20 a 40 cm; enquanto que I6 foi inferior a NV na profundidade de 50 a 100 cm. As análises de simulação a longo prazo mostraram um aumento de ECS de 12 e 13 Mg ha-1 para as áreas I6 e I4, respectivamente, em comparação com NV em 2100. Os resultados deste estudo são pioneiros em relação aos estudos de ECS nas mudanças de manejo e práticas de irrigação. Esta informação pode ser usada como base para a decisão de políticas públicas que lidam com o uso da terra e do aquecimento global
4

Evaluation of soil carbon stocks in response to management changes in sugarcane production / Avaliação do estoque de carbono do solo devido à mudança de manejo no sistema de produção da cana de açúcar

Caio Fernandes Zani 15 May 2015 (has links)
Brazilian commodities, such as ethanol, are looking for sustainable production to suit the international market demands. An important parameter for assessing sustainability is the carbon (C) footprint calculation of the product. Thus, studies of the variations in soil C stocks on the ethanol production are essential. Studies in relation to land use change are already been developed; however information about parameters of management changes on the sugarcane production is needed. The aim of this research was to evaluate the soil C stock in response to two main management changes in sugarcane production: i) no vinasse to vinasse application (NV-V), ii) burned to unburned harvesting system (B-UB). We also evaluated soil C stock changes in a chronosequence irrigation practices (native vegetation (NV), sugarcane irrigated 4 years (I4) and 6 years (I6), a new management in semi-arid and drought regions in Brazil which also aims high yields. Modelling approaches in order to assess long-term effects were also analysed. The NV-V transition showed higher soil C stock for V regime for topsoil layers 0-40 cm depth mainly due to the addition of organic compounds to the soil. Vinasse can also enhance biomass production and crop yield. The B-UB transition showed higher soil C stock in the UB regime from 20 to 60 cm depth due to higher organic matter accumulation from the maintenance of the straw to the field. The cumulative soil C stock for 1 metre depth had an increase of 1.1 and 0.75 Mg C ha-1 y-1 in the NV-V and B-UB transitions, respectively. From modelling was observed that V and UB sites had an increase of soil C stock by 2150, being a difference of 2.8 and 23 Mg ha-1 in the equilibrium state between NV-V and B-UB regimes, respectively. In the irrigation practices, the I4 showed higher soil C stock than NV in the 20 to 40 cm; while I6 was lower than NV in the 50 to 100 cm depth. Simulated long-term analyses showed increase of topsoil C stock of 12 and 13 Mg ha-1 for I6 and I4 area, respectively, compared to NV on 2100. The results in this study are pioneers in relation to soil C stock studies in the management transitions and irrigation practices. This information may be used as a basis for public policies decision which dealing of the land use and global warming / Commodities brasileiras, como o etanol, estão à procura de uma produção sustentável para atender às exigências do mercado internacional. Um parâmetro importante para avaliar a sustentabilidade é o cálculo da pegada de carbono (C) do produto. Assim, os estudos sobre as variações nos estoques de carbono do solo (ECS) sobre a produção de etanol são essenciais. Estudos em relação à mudança no uso da terra já estão sendo desenvolvidos; no entanto informações sobre parâmetros de mudanças de manejo na produção de cana de açúcar são necessárias. O objetivo desta pesquisa foi avaliar o ECS em resposta a duas principais mudanças de manejo: i) não vinhaça para aplicação de vinhaça (NV-V), ii) sistema queimado para não queimado (B-UB). Mudanças de ECS também foram avaliadas em sistemas de irrigação em cronoseqüência: vegetação nativa (NV), cana de açúcar irrigada por 4 anos (I4) e por 6 anos (I6). Modelagem matemática para avaliar o efeito a longo prazo também foi analisada. A transição NV-V apresentou maior ECS para o regime V em 40 cm de profundidade, devido principalmente à adição de compostos orgânicos ao solo. A vinhaça também pode aumentar a produção de biomassa e rendimento da cultura. A transição B-UB apresentou maior ECS no regime UB em 20-60 cm de profundidade devido ao acúmulo de matéria orgânica a partir da manutenção da palha no campo. O ECS acumulado para 1 metro de profundidade obteve um aumento de 1,1 e 0,75 Mg C ha-1 y-1 nas transições NV-V e B-UB, respectivamente. A partir de modelagem foi observado que os regimes V e UB obteve um aumento de ECS em 2150, sendo uma diferença de 2,8 e 23 Mg ha-1 no estado de equilíbrio para os regimes NV-V e B-UB, respectivamente. Nas práticas de irrigação, o I4 foi superior ao NV nos 20 a 40 cm; enquanto que I6 foi inferior a NV na profundidade de 50 a 100 cm. As análises de simulação a longo prazo mostraram um aumento de ECS de 12 e 13 Mg ha-1 para as áreas I6 e I4, respectivamente, em comparação com NV em 2100. Os resultados deste estudo são pioneiros em relação aos estudos de ECS nas mudanças de manejo e práticas de irrigação. Esta informação pode ser usada como base para a decisão de políticas públicas que lidam com o uso da terra e do aquecimento global
5

Use and Abuse of Southwestern Rivers: The Pueblo Dweller

DiPeso, Charles C. 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 / In response to the 20th century crisis of environmental destruction by unrestricted technological exploitation, some archaeologists are studying alternative modes of resource development as practiced by earlier men. The pueblo Indians of the arid southwestern deserts were basically upland corn farmers, who, after A.D. 1000, found it necessary to exploit their environment because of varying combinations of climatic change and increased population pressures. In the northeastern part of the state of Chihuahua, urban engineers, ca 1050, harnessed the entire Casas Grandes dendritic pattern by installing a set of linked hydraulic appointments which included various upslope protective devices such as linear border, check dams and riverside and hillside terraces. Not only were they able to visualize an entire dendritic pattern as the target area, but also they were able to conceive of rainfall and topsoil as a single factor in their control designs. Although large amounts of human labor were needed to construct and maintain these systems, few raw materials were needed. When the mountain-born waters reached the lower valleys, they were clear and sluggish, did not flood the bottomlands, and because of the reduced speed, could easily be diverted into canals and reservoirs, supplying the cities with domestic water and the farmers with irrigation water. Many further studies are needed of these pre-Columbian systems.
6

Use and Abuse of Southwestern Rivers: Historic Man - The Spaniard

Polzer, Charles W. 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 / The early Spanish explorers did not lean toward rivers and boats. Bred in the culture of an arid land, they naturally explored with horses or by foot, leaving boats and rafts to the English and French. No historical records reveal any Spanish desires or attempts to control river flow or harness desert water resources on any appreciable scale. Yet they transformed the Sonoran desert into a productive garden land never before achieved by indigenous peoples. Pueblos were built on river banks where alluvial fans could be easily irrigated. Small arroyo check dams diverted water into wells and town tanks, while larger diversion dams were built to draw water into canals for crop irrigation. The dams were designedly weak and efficient only to the point of diverting sufficient water for the pueblo. There is no concept of storing water in reservoirs or lakes for periods of scarcity, but only of tapping enough water during periods of excess flow. All surplus water was allowed to flow downstream for the use of others in their struggle for survival. In this way the Spanish achieved a balance between human needs and the limited resources of the desert. The records of the Mexicans and the Anglos have been much more exploitive and destructive.
7

Simple Time-Power Functions for Rainwater Infiltration and Runoff

Dixon, R. M., Simanton, J. R., Lane, L. 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 / The equations of Darcy, Kostiakov, Ostashev, Philip, and four modified Philip equations were evaluated for use in predicting and controlling rainwater infiltration and rainfall excess in crop and rangelands. These eight equations were least- square fitted to data from ring, border-irrigation, closed-top, and sprinkling infiltrometers. Kostiakov's equation satisfied the evaluation criteria better than the other seven equations. The parameters of Kostiakov's equation were physically interpreted by relating their magnitudes to some physical, biological, and hydraulic characteristics of the infiltration system. These characteristics included several infiltration abatement and augmentation processes and factors that are controlled at the soil surface by land management practices. The eight equations were also fitted to rainfall data to permit calculating runoff from small surface areas about the size of a typical crop plant. Comparison of the regression curves for infiltration and rainfall suggested that land management practices that appropriately alter the soil surface will permit wide-range control of infiltration, runoff, and erosion; and thereby achieve conservation and more efficient use of soil and water resources for crop production. The most important soil surface conditions affecting infiltration were microroughness, macroporosity, plant litter, and effective surface head.
8

Use and Abuse of Southwestern Rivers: The Desert Farmer

Ayres, J. E. 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 / The pre-Columbian Hohokam Indians occupied the major river drainages of central Arizona, and have been the subject of much intense archaeological research. Evidence indicates that the Hohokam began using river water for crop irrigation about 300 B.C., and modified and improved their irrigation systems over time, until the maximum extent of these systems was achieved about 900 a. D. Two types of water control seem to have been utilized: (1) the direct exploitation of rivers through the use of irrigation canals, (2) indirect use through controlled runoff within microdrainages at higher elevations before it reached the rivers. At first, probably only those parcels of land with optimal soils and drainage were used, but apparently population increases fostered by agriculture itself, combined with increasing social and political complexity, necessitated more and more exploitation of marginal lands. Eventually soil problems increased, imposing severe limitations on agriculture. These involved salt and alkali accumulation due to inadequate drainage, soil density and water logging. Additionally, the extension of cropping required the clearing of natural vegetation, which resulted in increased erosion and decreased available native food resources for periods when crops failed. The culture vanished completely about 1450 a. D., probably mainly because of their manner of river exploitation for irrigation. More recent archaeological studies are concentrating not only on river use but also on river abuse.
9

Responding to water demand strategies : case study in the Lower Orange catchment management area (LOCMA) / C.M. Gouws.

Gouws, Catharina Maria January 2010 (has links)
This study is an investigation into water management policies in South Africa, their effect on water users and the perceptions users have of these policies. The investigation begins with an exposition of concepts such as water demand management (WDM), as well as integrated water resource management (IWRM). A sub-discourse of the main theme is the societal tendency to neglect its common property. Garret Hardin's groundbreaking observations on the "tragedy of the commons" (1968) are explored in an effort to locate issues of relevance in effective water management strategies. In contemplating the commons, it is evident that aspects of morality and ethics are involved. The morality of a society be it in a global or national context, seems to manifest itself in legislation and policies, and in the way these are implemented. The relevance of good governance, hydropolitics and sustainable development is also discussed to provide the necessary theoretical background to an understanding of the relationship between consumers and the water commons. Access to safe drinking water is protected in the Constitution of the Republic of South Africa Act, 108 of 1996. Flowing from the government's obligation to take reasonable legislative and other measures to achieve the progressive realisation of fundamental human rights stipulated in section 27(2) of the Constitution, the challenge since 1994 has been to provide access to water for all inhabitants and to manage the available water resources effectively. Furthermore, the objective of subsequent water legislation such as the National Water Act, 36 of 1998 and regulatory plans, like the National Water Resource Strategy has been to incorporate international trends in water governance. The Department of Water and Environmental Affairs (DWEA) divided South Africa into 19 regions, called water management areas (WMA). In this study, attention is focused on what constitutes a catchment and how a catchment management agency (CMA) governs its water resources. A description is provided of the functions of water user associations (WUAs) and how ththe Lower Orange Catchment Management Area is, for example, the blueprint from which stakeholders develop their goals. In this study, the water situation in the Lower Orange Water Management Area is under scrutiny. The focus is on the three main institutional components of water management (the Lower Orange catchment management, the Upington Islands Water User Association [UIWUA] and the //Khara Hais Local Municipality). The progress of the establishment of the Lower Orange Catchment Management Agency is outlined over a period of five years. Meanwhile, the Upington Islands Water User Association was developed and this has grown in stature. The work being done by these institutions is investigated by looking at grassroots effects, especially in respect of irrigation activities. The unique water management circumstances of the //Khara Hais Local Municipality are then investigated along with the plans outlined in their Integrated Development Plan {lOP) and their Water Services Development Plane Internal Strategic Perspective (ISP) of(WSDP). Because local irrigation operations consume most of the available surface water in the Lower Orange Water Management Area, irrigation farmers and their activities warrant closer attention. A historical overview is given of the development of irrigation in the region followed by an assessment of the role of two of the most prominent historical figures in Upington, Reverend Adriaan Schroder and Abraham "Holbors" September. Ultimately, however, the focus falls on the current state of irrigation in the area. It is possible to distinguish between the approach of large commercial farming operations and that of smaller irrigation farming units to irrigation. Specific attention is given to the perceptions of irrigation farmers as far as the policies and legislation pertaining to water issues is concerned. This study will hopefully provide the Department of Water and Environmental Affairs(DWEA), //Khara Hais Local Municipality and organised agriculture with some recommendations on efficient integrated water management strategies. It might well be of value to other municipalities who are experiencing similar problems. The aim has been to identify typical problems and potential disputes between water management institutions and relevant role-players. / Thesis (Ph.D. (Public Management and Administration))--North-West University, Vaal Triangle Campus, 2010.
10

Responding to water demand strategies : case study in the Lower Orange catchment management area (LOCMA) / C.M. Gouws.

Gouws, Catharina Maria January 2010 (has links)
This study is an investigation into water management policies in South Africa, their effect on water users and the perceptions users have of these policies. The investigation begins with an exposition of concepts such as water demand management (WDM), as well as integrated water resource management (IWRM). A sub-discourse of the main theme is the societal tendency to neglect its common property. Garret Hardin's groundbreaking observations on the "tragedy of the commons" (1968) are explored in an effort to locate issues of relevance in effective water management strategies. In contemplating the commons, it is evident that aspects of morality and ethics are involved. The morality of a society be it in a global or national context, seems to manifest itself in legislation and policies, and in the way these are implemented. The relevance of good governance, hydropolitics and sustainable development is also discussed to provide the necessary theoretical background to an understanding of the relationship between consumers and the water commons. Access to safe drinking water is protected in the Constitution of the Republic of South Africa Act, 108 of 1996. Flowing from the government's obligation to take reasonable legislative and other measures to achieve the progressive realisation of fundamental human rights stipulated in section 27(2) of the Constitution, the challenge since 1994 has been to provide access to water for all inhabitants and to manage the available water resources effectively. Furthermore, the objective of subsequent water legislation such as the National Water Act, 36 of 1998 and regulatory plans, like the National Water Resource Strategy has been to incorporate international trends in water governance. The Department of Water and Environmental Affairs (DWEA) divided South Africa into 19 regions, called water management areas (WMA). In this study, attention is focused on what constitutes a catchment and how a catchment management agency (CMA) governs its water resources. A description is provided of the functions of water user associations (WUAs) and how ththe Lower Orange Catchment Management Area is, for example, the blueprint from which stakeholders develop their goals. In this study, the water situation in the Lower Orange Water Management Area is under scrutiny. The focus is on the three main institutional components of water management (the Lower Orange catchment management, the Upington Islands Water User Association [UIWUA] and the //Khara Hais Local Municipality). The progress of the establishment of the Lower Orange Catchment Management Agency is outlined over a period of five years. Meanwhile, the Upington Islands Water User Association was developed and this has grown in stature. The work being done by these institutions is investigated by looking at grassroots effects, especially in respect of irrigation activities. The unique water management circumstances of the //Khara Hais Local Municipality are then investigated along with the plans outlined in their Integrated Development Plan {lOP) and their Water Services Development Plane Internal Strategic Perspective (ISP) of(WSDP). Because local irrigation operations consume most of the available surface water in the Lower Orange Water Management Area, irrigation farmers and their activities warrant closer attention. A historical overview is given of the development of irrigation in the region followed by an assessment of the role of two of the most prominent historical figures in Upington, Reverend Adriaan Schroder and Abraham "Holbors" September. Ultimately, however, the focus falls on the current state of irrigation in the area. It is possible to distinguish between the approach of large commercial farming operations and that of smaller irrigation farming units to irrigation. Specific attention is given to the perceptions of irrigation farmers as far as the policies and legislation pertaining to water issues is concerned. This study will hopefully provide the Department of Water and Environmental Affairs(DWEA), //Khara Hais Local Municipality and organised agriculture with some recommendations on efficient integrated water management strategies. It might well be of value to other municipalities who are experiencing similar problems. The aim has been to identify typical problems and potential disputes between water management institutions and relevant role-players. / Thesis (Ph.D. (Public Management and Administration))--North-West University, Vaal Triangle Campus, 2010.

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