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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.
271

Three Essays on Economic Development in Africa

Musumba, Mark 2012 August 1900 (has links)
To achieve economic development, regional authorities have to address issues that relate to climate change, efficient information flow in the market place, and health care. This dissertation presents three essays on current issues of concern to economic development in Africa. Climate change is examined in terms of its effects on the Egyptian agricultural sector; transmission of world price to small scale growers is examined in Uganda; and the benefits of insecticide-treated bed nets use is examined in Africa. In essay I, to address the impact of climate change on the Egyptian agricultural sector under alternative population growth rates, water use and crop yield assumption; the Egyptian Agricultural Sector Model (EASM) is updated and expanded to improve hydrological modeling and used to portray agricultural activity and hydrological flow. The results indicate that climate change will cause damages (costs) to the Egyptian agricultural sector and these will increase over time. Egypt may reduce these future damages by controlling its population growth rate and using water conservation strategies. In essay II, I use vector autoregressive analysis to examine the transmissions of price information to Uganda coffee growers; using monthly coffee price data on retail, futures, farmgate and world prices from 1994 to 2010. Improved transmission of world prices to farmers may increase their decision making to obtain a better market price. Directed acyclic graphs reveal that there is a causal flow of information from the indicator price to the London futures price to the Uganda grower?s price in contemporaneous time. Forecast error variance decomposition indicates that at moving ahead 12 months, the uncertainty in Uganda grower price is attributable to the indicator price (world spot price), own price (farmgate), London future and Spain retail price in rank order. In essay III, the cost of malaria in children under five years and the use of insecticide treated bed nets is examined in the context of 18 countries in Africa. I examine the direct and indirect cost of malaria in children under five years and the benefit of investing in insecticide treated mosquito nets as a preventative strategy in 18 African countries. The results indicate that the use of mosquito treated nets reduces the number of malaria cases in children; and this can induce 0.5% reduction in outpatient treatment costs, 11% reduction in inpatient treatment costs, 11% reduction in productivity loss, and 15% reduction in disability adjusted life years (DALY) annually.
272

From conduits to communities : plant water use strategies and evapotranspiration in a semi-arid ecosystem in south-western Australia

Mitchell, Patrick John January 2009 (has links)
[Truncated abstract] Understanding the ecohydrological dynamics of native vegetation can provide a benchmark for future efforts to restore landscape hydrology and allow predictions of potential landscape responses to climate uncertainty and associated changes in vegetation cover. The key drivers of evapotranspiration (Et) involved in maintaining a hydrological balance that minimises deep drainage in semi-arid ecosystems operate at a range of scales, and in this thesis I assessed the water relations of functionally and taxonomically diverse plant communities in south-western Australia from the leaf-level to ecosystem scale. For three key communities; heath shrubland, mallee (small multistemmed eucalypt) -heath, and open eucalypt woodland, populating a typical catenary sequence of soil types along a slope, I addressed the following questions: 1) What are the predominant water use strategies of wheatbelt native plant communities and what underlying trade-offs determine the distribution of plant water use strategies along the topographical gradient? 2) What are the roles of soil water and hydraulic limitation in controlling the spatial and temporal dynamics of transpiration in different functional types? 3) What is the magnitude and partitioning of total Et in the woodland community and what processes determine Et fluxes on a seasonal and annual basis? 4) What are the seasonal differences in Et among contrasting community-types and how do these patterns relate to canopy attributes and transpiration capacity along the topographical gradient? A key philosophical step in working with species-rich communities was to develop the concept of 'hydraulic functional types' (HFTs) to identify groupings of species using associations of physiological and morphological traits that define their hydrological functioning. .... However, as shallow soils dried during spring and summer, Et fluxes were significantly lower at the heath site (0.35 versus 0.66 mm day-1 for the woodland in February), demonstrating that the seasonality of Et fluxes differentiates communityscale contributions to regional water balance. Land-surface exchange of water over native vegetation is by no means uniform, but varies according to the spatial and temporal availability of water along topographical gradients. In general, shallow soils present fewer opportunities for water use partitioning and favour drought hardiness and a transpiration response that tracks recent rainfall patterns, whereas deeper soils promote greater differentiation in water use strategy and support canopies responsive to atmospheric demand. This thesis provides a unique description of ecosystem water balance in a global biodiversity hotspot by viewing complex vegetation mosaics in terms of their relevant hydrological units. This information is fundamental to sustainable agroforestry and revegetation efforts and our ability to gauge possible changes in vegetation structure and function under a changing climate.
273

Lucerne (Medicago sativa) productivity and its effect on the water balance in southern Western Australia

Dolling, Perry January 2006 (has links)
[Truncated abstract] In southern Western Australia the replacement of deep-rooted native vegetation with annual species has resulted in rising water tables and increased salinity due to insufficient water use. The area has a Mediterranean-type climate where rainfall during summer is generally low but variable resulting in limited plant growth. However, if rainfall does occur it potentially can contribute to to the increased water excess or drainage by increasing the soil water content before the main drainage period in winter. The first study investigated factors controlling soil water content changes during the fallow (December to May) in annual farming systems. This was achieved by examining variation in available soil water storage to a depth of 1.0-1.5 m at three sites within 13 seasons. Reasons for the variation were examined using the Agricultural Production Systems Simulator (APSIM). This study also investigated the relationship between soil water content at the end of the fallow period (1 May) and the amount of drainage below 2.5 m by using APSIM coupled to historical weather records at three locations. At the end of the fallow a mean of 24 mm (or 25%) of rainfall during the fallow was retained in the soil. Losses of soil water during the fallow were due to evaporation (mean of 60 mm), transpiration from plant cover (mean of 12 mm) and drainage below the root zone and run off (combined mean of 13 mm). Soil water accumulation during the fallow period had a significant impact on simulated drainage under wheat in the following growing season. Every 1 mm increase in soil wetness at the end of the fallow resulted in a 0.7-1 mm increase in simulated drainage during the growing season. ... Variation in the water excess due to variation in rainfall was greater than the reduction in water excess due to lucerne. This makes the decisions about when to grow lucerne to reduce water excess difficult if livestock enterprises are less profitable than cropping enterprises. The findings of this PhD indicate that lucerne does have a place in Mediterranean-type environments because of its greater water use than current farming practices. However, its use needs to be strategic and the strategy will vary from region to region. For example, in the low rainfall region lucerne sowings need to be matched with high soil water contents and phase length will generally be short (2-3 years). In comparison at high rainfall regions lucerne will need to be grown for longer or combined with other strategies to increase water use.
274

Usages de l'eau dans la vie privée, au moyen age, à travers l'iconographie des manuscrits à peintures de l'Europe septentrionale (XIII-XVIe siècle) /

Gouedo-Thomas, Catherine. January 1900 (has links)
Thesis (Ph. D.)--Ecole des Hautes Etudes en Science Sociales de Paris, 1995. / Includes bibliographical references (p. 186-194).
275

Usages de l'eau dans la vie privée, au moyen age, à travers l'iconographie des manuscrits à peintures de l'Europe septentrionale (XIII-XVIe siècle) /

Gouedo-Thomas, Catherine. January 1900 (has links)
Thesis (Ph. D.)--Ecole des Hautes Etudes en Science Sociales de Paris, 1995. / Includes bibliographical references (p. 186-194).
276

Negotiating an international regime for water allocation in the Mekong River Basin

Browder, Greg. January 1998 (has links)
Thesis (Ph. D.)--Stanford University, 1998. / Includes bibliographical references (leaves 349-357).
277

Groundwater management plan in the Bandung Basin

Shintodewi, Putri Andhini. January 2000 (has links) (PDF)
Bibliography: leaves 97-99. Aims to set a groundwater management plan for the Bandung Basin that attempts to take a holistic approach to an improved groundwater management in conjunction with surface water and land management, and to provide a long-term sustainable management plan.
278

Irrigação subsuperficial deficitária no cultivo de tomateiro em casa de vegetação

Mendonça, Thaís Grandizoli 17 April 2017 (has links)
Submitted by Ronildo Prado (ronisp@ufscar.br) on 2017-08-16T20:20:29Z No. of bitstreams: 1 DissTGM.pdf: 2889804 bytes, checksum: c55eea68163f4e92468140f7d3ced089 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-16T20:20:36Z (GMT) No. of bitstreams: 1 DissTGM.pdf: 2889804 bytes, checksum: c55eea68163f4e92468140f7d3ced089 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-16T20:20:43Z (GMT) No. of bitstreams: 1 DissTGM.pdf: 2889804 bytes, checksum: c55eea68163f4e92468140f7d3ced089 (MD5) / Made available in DSpace on 2017-08-16T20:20:49Z (GMT). No. of bitstreams: 1 DissTGM.pdf: 2889804 bytes, checksum: c55eea68163f4e92468140f7d3ced089 (MD5) Previous issue date: 2017-04-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The tomato is a demanding crop in regards to water and is among the most consumed vegetables in Brazil. The search for alternatives to improve tomato productivity, as well as reduce the water use in the crop cycle, is essential for agricultural production and environment. The objectives of this work were to evaluate the contribution of subsurface drip irrigation to yield and fruit quality of Grape tomatoes and to estimate the water use efficiency (EUA). The experiment was carried out in the CCA / UFSCar and consisted of three treatments with four randomized blocks. Irrigation management considered the storage soil water capacity (CAD), the soil moisture being high according to the water content reference of the treatment, 0.33 (T1), 0.29 (T2) and 0.25 m3 m-3 (T3), corresponding to 100 % replacement of CAD, and deficit irrigations of 75 and 50 % of CAD, respectively. Water content was monitored by TDR probes and the roots depth obtained through a root images scanner. The Grape tomatoes were transplanted under drip lines installed at 0.20 m depth. Quantitative and qualitative characteristics of the fruits were evaluated in relation to the proposed treatments, being: fruits number per plant, average fruit mass and productivity, quantitative characteristics and; Diameter, length, soluble solids, fruit pH and dry mass of leaves and stem, qualitative characteristics. The total water applied was 1297 mm in T1, 471 mm in T2 (36 % of water applied in T1) and 234 mm in T3 (18 % of T1). Among the characteristics evaluated, the T2 did not differ from the T1 treatment, except in the diameter and pH. The T3 treatment was equal to T1 only in the fruits number per plant. The average fruit mass was different among all treatments and there was no difference between soluble solids values. The T3 treatment obtained higher EUA, followed by T2 and T1, but did not have higher productivity nor better results in other evaluated attributes. Deficit subsurface irrigation of 75 % of CAD did not interfere in Grape tomato productivity and fruit quality, being the most recommended because of qualitative and quantitative attributes similar to full irrigation and to increase the EUA. It is concluded that deficit subsurface irrigation had productivity and fruit quality of Grape tomatoes like full irrigation when used 75 % of CAD, increased the water use efficiency and contributed with water use reduction in crop cycle. / O tomateiro é uma cultura exigente em água e está entre as hortaliças mais consumidas no Brasil. A busca por alternativas que melhorem sua produtividade, bem como reduzam o uso da água no ciclo da cultura, é essencial para a produção agrícola e para o meio ambiente. Este trabalho teve o objetivo avaliar a contribuição da irrigação subsuperficial deficitária na produtividade e qualidade dos frutos de tomateiros Grape e estimar a eficiência no uso da água (EUA). O experimento foi realizado no CCA/UFSCar e consistiu de três tratamentos com doze parcelas em blocos casualizados. O manejo da irrigação levou em consideração a capacidade de água disponível no solo (CAD), sendo a umidade do solo elevada de acordo com a umidade de referência do tratamento, 0,33 (T1), 0,29 (T2) e 0,25 m3 m-3 (T3), correspondendo à reposição de 100 % da CAD, e irrigações deficitárias de 75 e 50 % da CAD, respectivamente. A umidade do solo foi monitorada por sondas TDR e o crescimento das raízes por imagens obtidas através de scanner de raízes. As mudas de tomateiro Grape foram transplantadas sob linhas de gotejamento instaladas a 0,20 m de profundidade. Foram avaliados atributos quantitativos e qualitativos dos frutos em relação aos tratamentos propostos, sendo eles: número de frutos por planta, massa média dos frutos e produtividade como atributos quantitativos; diâmetro, comprimento, sólidos solúveis, pH dos frutos e massa seca das folhas e caule como atributos qualitativos. A lâmina total de água aplicada foi 1297 mm em T1, 471 mm em T2 (36 % da lâmina aplicada em T1) e 234 mm em T3 (18 % de T1). Entre os atributos avaliados, o diâmetro e pH dos frutos do tratamento T2 diferiram do T1. Já o tratamento T3 foi igual ao T1 apenas no número de frutos por planta. A massa média dos frutos foi diferente entre todos os tratamentos e não houve diferença no valor de sólidos solúveis. O tratamento T3 obteve maior EUA, seguido por T2 e T1, porém não teve maior produtividade e nem melhores resultados em outros atributos avaliados. A irrigação subsuperficial deficitária de 75 % da CAD não interferiu na produtividade do tomateiro Grape e na qualidade dos frutos, sendo a mais recomendada por apresentar atributos qualitativos e quantitativos similares à irrigação plena e aumentar a EUA. Conclui-se com este trabalho que irrigação subsuperficial deficitária teve produtividade e qualidade de frutos de tomateiro Grape semelhante à irrigação plena quando utilizado 75 % da CAD, aumentou a eficiência no uso da água e contribuiu com a redução no uso da água no ciclo da cultura.
279

Consumer behaviour with respect to domestic water in Mauritius including a model

Sowdagur, Daramdeo 31 July 2006 (has links)
Literature survey shows that with, a few exceptions, the consumer behaviour of domestic water consumers has not been a common area of research. This explains the scarcity of information in this specific field. This scarcity was noted in the region and very much so in the context of Mauritius. And yet, such information is very much relevant for the management of the water sector, for the improvement of the service, for policy makers, for personal and social development and for achieving consumer satisfaction. This research brings about information that would contribute in its own way to these areas. The object of this thesis is to study the consumer behaviour in respect of domestic water consumers in Mauritius, to develop new theories and to build a consumer behaviour model. The thesis, at its outset, gives the background of the research. It contains the description of the water supply situation in Mauritius, its production, its distribution and its management. The brief on the people of Mauritius helps to put in the right context the pluricultural nature of the Mauritian society which is important for the understanding of the consumer behaviour of Mauritians. The literature survey, inter-alia, gives the historical development of consumer behaviour, its relevance to marketing, and its study as a discipline in its own right. The very scarcity of theories and models of consumer behaviour of domestic water consumers cannot be overlooked. The literature survey, therefore, covers some of the theories and models specifically on commodities. These models along with the literature review serve as theoretical foundation for the present research The models of consumer behaviour which have been literature reviewed have further enabled to construct an integrated model of consumer behaviour which serves as a framework for the discussion and analysis of the new model which is developed during the course of this research. The research is one mainly of general interest and can be classified as an exploratory research with a substantial contribution of descriptive research. The research has necessitated the collection of primary data. For this purpose, the objective approach was adopted and a consumer survey was carried out with the use of a direct structured questionnaire. The survey has been supplemented by discussions of focus groups. The analysis of the consumer survey is followed by the testing of the hypotheses, the development of theories and discussions on results obtained. The building of a new model of consumer behaviour based on the findings of the research is then undertaken and discussed. The thesis covers a wide spectrum from the need of a domestic water connection, consumption of domestic water, post-consumption behaviour to the illegal use of water in Mauritius. The thesis winds up with conclusions and recommendations. The specific topic of this thesis is a rare one. This research is but a step in the furtherance of knowledge. It stands as an original regional contribution to the science of management and to its development. / Graduate School of Business Leadership / DBL
280

Cultivo do girassol irrigado sob diferentes lâminas de água e doses de nitrogênio / Sunflower cultivation irrigated under different water blades and nitrogen doses

Freire, Jonas de Oliveira 29 August 2016 (has links)
Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-02-14T19:11:01Z No. of bitstreams: 1 JonasOF_TESE.pdf: 3319263 bytes, checksum: 51b79bea8bd5a5a042d4db215bfe1a86 (MD5) / Approved for entry into archive by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-02-15T14:50:14Z (GMT) No. of bitstreams: 1 JonasOF_TESE.pdf: 3319263 bytes, checksum: 51b79bea8bd5a5a042d4db215bfe1a86 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-02-15T14:52:02Z (GMT) No. of bitstreams: 1 JonasOF_TESE.pdf: 3319263 bytes, checksum: 51b79bea8bd5a5a042d4db215bfe1a86 (MD5) / Made available in DSpace on 2017-03-21T14:53:47Z (GMT). No. of bitstreams: 1 JonasOF_TESE.pdf: 3319263 bytes, checksum: 51b79bea8bd5a5a042d4db215bfe1a86 (MD5) Previous issue date: 2016-08-29 / Sunflower adapts to different conditions of climate and soil, including the prevailing climate in the Northeast, but the water needs, as well as nitrogen fertilizer recommendations are not yet fully defined. The objective of this study was to evaluate sunflower productivity and efficiency of water and nitrogen use. The experiment was conducted between October 2013 to January 2014 in Unidade Agrícola Industrial Escola do Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Norte (IFRN/Campus Apodi), Apodi, in the state of Rio Grande do Norte, Brazil. Statistical design used was in blocks in the 4 x 4 factorial scheme with four replications. The treatments consisted of four water slides 58, 80, 100 and 120% of crop evapotranspiration (ETc) associated with four doses of nitrogen 40, 100, 200 and 370% of the dose recommended for the cultivation of 70 kg ha-1. The depth water of 517 mm (108% ETc) associated with nitrogen dose of 77 kg ha-1 provided 91.3% of the maximum productivity, these being the doses recommended in the studied conditions. The oil productivity depending on depths water and nitrogen levels followed the trend surface function in oil yield of water depths and doses of nitrogen. The water factor was most limiting characteristics evaluated the nitrogen fertilization / O girassol se adapta a diferentes condições de clima e solo, inclusive ao clima predominante na Região Nordeste, porém, as necessidades hídricas, assim como as recomendações de adubação nitrogenada, ainda não estão perfeitamente definidas. Objetivouse com o presente estudo, avaliar a produtividade do girassol e a eficiência do uso da água e nitrogênio. O experimento foi conduzido no período de 29 outubro de 2013 a janeiro de 2014 na Unidade Agrícola Industrial Escola do Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Norte (IFRN/Campus Apodi), Apodi, RN. O delineamento estatístico adotado foi em blocos no esquema fatorial 4 x 4 com quatro repetições. Os tratamentos consistiram em quatro lâminas de irrigação 58, 80, 100 e 120% da evapotranspiração da cultura (ETc) associadas a quatro doses de nitrogênio 40, 100, 200 e 370% da dose padrão de 70 kg ha- 1. A lâmina de água de 517 mm (108% da ETc) associada a dose nitrogenada de 77 kg ha-1 proporcionou 91,3% da produtividade máxima de grãos, sendo estas as doses recomendadas nas condições estudadas. A produtividade de óleo em função das doses de água e nitrogênio acompanhou a tendência da superfície do rendimento de óleo em função das lâminas de água e doses de nitrogênio. As lâminas de água foram mais limitantes às características avaliadas que a adubação nitrogenada / 2017-02-14

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