The objectives of the study are to: (1) Critically analyse the 1959 Nile River agreements from a human rights perspective (2) examine the applicability of international human rights law in water distribution and use and (3) investigating how human rights norms and principles can be used, if at all, as a means of solving water conflicts over the use of trans-boundary rivers. The study adopts a human rights approach in its consideration of the problem of conflicts that may arise in connection with the use of trans-boundary rivers. It is particularly significant as it seeks to explore the solution from the human rights of the people in the riparian countries. It is believed that the study will contribute to the development of basin-wide cooperation among riparians by being employed in negotiations and planning of projects. / Thesis (LLM (Human Rights and Democratisation in Africa))--University of Pretoria, 2008. / Dissertation submitted to the Faculty of Law University of Pretoria, in partial fulfilment of the requirements for the degree Masters of Law (LLM in Human Rights and Democratisation in Africa). Prepared under the supervision of Dr Raymond A. Atuguba of the Faculty of Law, University of Ghana Legon, Accra, Ghana / http://www.chr.up.ac.za/ / Centre for Human Rights / LLM

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Philosophiae Doctor - PhD / Orchard evapotranspiration (ET) is a complex flux which has been the subject of many studies. It often includes transpiration from the trees, cover crops and weeds, evaporation from the soil, mulches, and other orchard artefacts. Studies of evapotranspiration in orchards often quantify tree water use and soil evaporation, treating the water use from the understorey vegetation on the orchard floor as negligible. Therefore, there is a paucity of information; first about the water use of cover crops in general, and secondly about the contribution of cover crops to whole orchard ET. This information is important, especially in semi-arid regions like South Africa where water resources are already under great strain and the situation is predicted to worsen in future due to climate change.

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The occurrence of water crises in many parts of the world raises the need to consider more efficient and sustainable consumption of water resources. As such, many cities have prioritised water demand management strategies, which are based on price and non-price mechanisms. The literature shows no consensus as to which of these measures are most effective for managing residential water demand. To understand the impact and effectiveness of these mechanisms, there is a need to understand how people respond to them. This requires understanding materials, meanings and competences (skills and know how) that people have, which constitute elements of social practice. In 2017 and 2018, the City of Cape Town (CoCT) ramped up their price and non-price mechanisms to encourage people to save water in response to a severe drought. These mechanisms included water restrictions, increased water tariffs, and the Day Zero communication campaign. However, little is known about how effective these measures were at encouraging people to save water. There is no clear documentation of how the public understands, interprets and incorporates these mechanisms into their own household water use practices. This study explores the impacts and effectiveness of the City of Cape Town’s price and non-price mechanisms on household water use practices during the water crisis. Using information obtained through semi-structured interviews with 20 individuals living in houses where they paid their water bills, a version of social practice theory is used as a lens to understand how respondents interpreted and responded to these mechanisms when it comes to residential water use practices. This allows for an assessment of which of the CoCT’s actions are more effective in achieving sustainable water use practices. Results show that price mechanisms (water tariffs) were considered to be ineffective and did not encourage people to save water. Non-price mechanisms (water restrictions and Day Zero communication campaign) were seen as having more impact on respondents, encouraging water conservation behaviour; especially when it comes to household indoor water use activities related to hygiene. Compared to other studies which have used estimates for the water demand function, this study conducted interviews directly with households on the impact of the mechanisms. This enabled this study to explain how and why household water use practices change in response to these measures. Such qualitative information is important and contributes to a field that often uses quantitative data to suggest whether price or non-price mechanisms are effective.

Fruit growers in Utah and other areas across the Intermountain West are faced with growing production challenges stemming from declining soil quality and water resources. Population growth presents challenges in terms of the cost and availability of land, but also presents opportunities in the form of new marketing options such as organic fruit. Few certified organic fruit orchards are operating in Utah currently, which is attributed to a lack of locally tested and adapted organic management practices. An organic peach orchard trial evaluated the effectiveness of different organic management approaches to enhance soil quality and conserve water without compromise to fruit tree growth and fertility. Two tree-row treatments: ‘straw mulch' (Triticum aestivum L.) and ‘living mulch’ (Lobularia maritima (L.) Desv.) were tested in combination with two alleyway groundcovers: ‘grass’ (Festuca rubra L. with Lolium perenne L.) and a legume, ‘Birdsfoot trefoil’ (Lotus corniculatus L.). The novel systems were compared with industry standards, tillage and weed fabric tree-rows with grass alleyways. Trefoil alleyway biomass deposited into tree-rows contributed an estimated 6.24 kg biomass and 0.21 kg total N/tree annually. Trefoil treatments had higher levels of organic carbon (C) and nitrogen (N), inorganic N, microbial biomass and enzyme activities, suggesting trefoil alleyways enhanced soil nutrient cycling, as well as C and N reserves in comparison to grass and tillage treatments. A functional gene array analysis was conducted to describe the mechanisms, microbial functional composition and diversity underlying the observed soil processes, however few differences were detected in soil community structure between soils under different orchard floor management. Significantly lower leaf δ15N in trees grown with trefoil compared to grass, and an association between root biomass, diameter and trunk cross-sectional area (TCSA) suggests nitrogen sources derived from the trefoil groundcover contributed to improved fruit tree vigor. Few differences resulted among orchard treatments for water use (mm/week). Trends indicated slightly higher water use in trefoil over grass, but not enough to offset observed soil quality and tree growth benefits. These findings suggest, trefoil alleyways may provide ecological benefits such as improved soil quality and efficient nutrient cycling, without substantial increases in water use.

There are two approaches to estimating the quantity of water required in an urban area: the requirements approach and the economic approach. The requirements approach extrapolates from past growth trends of the urban area. Water consumption and population are extrapolated into the future using a trend line based on prior years; the future requirements of the area are determined according to past experience. This approach served well when water was essentially a free good. But now that it is an economic good that requires production, the requirements approach tends to overestimate water requirements. The alternative is the economic approach which takes into account different characteristics of an urban area. Among these characteristics are economic, demographic, geographic and climatic. This approach leads to better use of information to estimate future water consumption. This dissertation is a cross-sectional analysis of municipal water districts in Oregon. It is based on the economic approach. Data on specified variables were collected by sampling and surveying more than 1,000 water districts in Oregon. The data were analyzed using Multiple Linear Regression. The general hypothesis of the study is that municipal water use in Oregon can be estimated by using independent variables other than size. Weather, per capita income, average price of water, marginal cost of water, the amount of fixed charge for basic water use, allowed quantity of basic water use, and non-residential connections were regressed on the per capita per day water consumption for residential, commercial, industrial and total users. The hypothesis was confirmed; price was a significant variable in the different uses of water. Climate was found to be significant in estimating the residential use. Variable charge as well as climate were found to be significant in commercial use. Fixed charge and sewage charge were somewhat significant in estimating the industrial use. The results of the study are consistent with the theory and the findings of previous studies. Three models were developed; a general model, a residential model and a non-residential model. These models helped to identify climate and price as effective variables in estimating water demand in the study area within the context of the economic approach.

Drought and salt stress are the main global factors that reduce the average yield of most major crops. In order to meet global demands, we will need to double food production by 2050 (Tilman, Balzer, Hill, & Befort, 2011). Plant growth-promoting bacteria (PGPB) are a group of bacteria that alleviate the harmful effects of abiotic stresses such as salt, heat and drought stress on plants and decrease the global dependence on hazardous agricultural chemicals. We identified that beneficial microbes isolated from desert plants (indigfera argentea) from Jizan region, in 2012 enhance the tolerance of a variety of crop plants to drought and salt stresses under laboratory conditions and in field trials. We analyzed the interaction of these bacteria with the plants by genetic, biochemical and imaging techniques. The goal of this dissertation is to ultimately improve our understanding of the mechanisms of drought and salt stress tolerance conferred by beneficial microbes that can be used as a sustainable solution for plants and crops in degrading lands (deserts) and land affected by abiotic stresses. Outlines how each of chapter of this dissertation will contribute to the discovery of novel drought and salt stress tolerance strategies using a desert-specific bacterial endophyte.

Demand for potable water and energy is increasing with growing populations and economies and many fear that scarcity of such resources will become a significant worldwide problem in the future. As such, promoting water and energy conservation in residential building environments has become an important focal area for research. Providing feedback of water or energy consumption to residential building occupants has been demonstrated to be effective in promoting water and energy conservation separately. However, although water and energy are inexorably connected, we lack research that investigates the bridge between water and energy in the representation of feedback to promote water conservation. In this paper, we describe a study that was designed to investigate the impact of two different representations of water consumption feedback on water conservation. Water consumption was represented to consumers in one of two different ways: 1) gallons and 2) gallons along with the estimated embodied energy of water consumption. The study was conducted in 18 residential halls at Virginia Tech and lasted approximately six weeks. The outcome of the study suggests that representing water consumption in terms of gallons together with the embodied energy associated with water consumption can lead to a statistically significant reduction in water conservation while representing water consumption only in terms of gallons may not. This has significant implications for future water feedback designed to promote water conservation and the study indicates that non-monetary approach can be taken. / Master of Science

Perennial ryegrass (Lolium perenne L.) is a cool-season turfgrass susceptible to low temperature injury. Wilt-based (WB) irrigation is a common practice in scheduling turf irrigation as an alternative to well-watered (WW). Moisture stress has been shown to promote cold hardiness but this has not been investigated in response to WB irrigation. Measurements of 13C isotope discrimination (DELTA) are useful predictors of water use efficiency (WUE), drought resistance, evapotranspiration (ET) and salinity tolerance but the relevance to turfgrass cold hardiness has not been determined. DELTA analyses may enable more efficient screening protocols in breeding for improved cold hardiness. Objectives of this study were to examine perennial ryegrass genotypes in relation to cold hardiness, DELTA and WUE in response to WW and WB irrigation schedules, to compare genetic diversity between top-performing (TP) and bottom-performing (BP) perennial ryegrass genotypes, and to assess the predictive value of DELTA of for cold hardiness. Six genotypes were selected based on turf quality from the most northern NTEP location (Orono, ME) and included three TP (‘All Star 2’, ‘Mach I’ and ‘Sunkissed’) and three BP (‘APR-1234’, ‘Buccaneer’ and ‘WVPB-R-82’) genotypes. ET, yield, WUE, shoot water content, rooting potential, wilting tendency, DELTA and median lethal temperatures (LT50) using whole-plant survival were measured from greenhouse samples grown in weighing lysimeters in 2007 and 2008. Plant measurements in both years were based on sampling conducted at the last cycle after 68-d of irrigation with 100% of ET applied at leaf-roll (WB) versus ET replacement every 4-d (WW). Lower LT50 values were generally associated with low yield, low WUE and low shoot water content, whether the result of irrigation treatment or genotypic variation. TP genotypes demonstrated significantly lower LT50 temperatures (greater cold hardiness) in comparison to BP genotypes in both years. Modest cold hardiness enhancement with WB irrigation was highest for TP genotypes. Wilting tendency and DELTA were not reliable predictors of cold hardiness, although individual TP genotypes exhibited responses distinctly different than some BP genotypes. Further research is needed to investigate the physiological mechanisms of enhanced turfgrass cold hardiness in response to moisture stress.