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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.
151

Impact of Land Management Practices on Water Balance and Sediment Transport in the Morogoro Catchment, Uluguru Mountains (Tanzania)

Kilemo, Dominico Benedicto 14 December 2017 (has links)
Tanzania, like other developing countries in the tropics is severely affected by the degradation of water resources owing to improper land management practices. Such practices affect water supply through soil erosion which does not only cause sedimentation of rivers and water bodies but also leads to a reduction in the rainwater infiltration capacity of soils. This thesis seeks to demonstrate how the implementation of proper land management measures can reduce soil erosion and increase water supply in the Morogoro River catchment (Uluguru Mountains). The proper practices referred to are the soil and water conservation (SWC) approaches which include contour farming, fanya juu terracing and bench terracing. The thesis combines social science and geoscience methods in a synergetic manner to address this research problem. To understand how and to what degree SWC methods affect water fluxes and sediment yields, the hydrological model SWAT (Soil and Water Assessment Tool) was applied. Before carrying out the modelling procedures, it was necessary to examine the level of SWC adoption among farmers and factors influencing the process so as to establish the baseline. To this end, biophysical and socio-economic factors assumed to affect farmers’ adoption tendency were examined using a household questionnaire. Modelling results indicate that if correctly implemented contour farming, fanya juu terracing and bench terracing would significantly reduce sediment yield at different rates. The reduction would range approximately between 1% - 85% with the highest percentage change achieved by practicing the three SWC methods simultaneously. However, such SWC measures would not increase water flow annually owing to evapotranspiration losses. Nevertheless, according to modelling results groundwater storage would be increased by about 14% and hence contributing to water supply during the dry season. The household questionnaire survey suggests that the adoption of SWC methods in the study area is very low and complex. While age of the head of household, access to extension (professional) services, household annual income and proximity to the farm significantly influenced farmers’ decision to adopt SWC, gender of the head of household, slope characteristics of the farm, number of adults in the household and farmer’s perception on soil erosion effects had no considerable influence on adoption. Therefore, to successfully realize the SWC benefits demonstrated by the modelling results, smallholder farmers upstream of the catchment should be incentivized to implement proper land management practices. Payment for ecosystem services scheme appears to be a suitable strategy. To make this operational, the Tanzanian government should establish a national water fund which will finance watershed management activities. The methodological approach employed in this thesis is transferrable to other sites with problems comparable to the studied catchment.
152

Characterizing Water and Nitrogen Dynamics in Urban/Suburban Landscapes

Sun, Hongyan 01 December 2011 (has links)
This research investigated the water use of different plant types in urban landscapes, nitrogen (N) and water transport in turf, and potential N leaching from urban landscapes to ground water. In the first study, three landscape treatments integrating different types of plants—woody, herbaceous perennial, turf—and putative water use classifications—Mesic, Mixed, Xeric—were grown in large drainage lysimeters. Each landscape plot was divided into woody, turf, and herbaceous perennial plant hydrozones and irrigated for optimum water status over two years, with water use measured using a water balance approach. For woody plants and herbaceous perennials, canopy cover, rather than plant type or water use classification, was the key determinant of water use relative to reference evapotranspiration (ETo) under well-watered conditions. For turf, monthly evapotranspiration (ETa) followed a trend linearly related to ETo. In the second study, water transport parameters were calibrated using an inverse simulation with Kentucky bluegrass (KBG). Subsequently, those parameters were applied to simulate water use by tall fescue (TF) and buffalograss (BG) turfgrasses using numerical modeling (Hydrus-1D). By using the calibrated soil hydraulic parameters obtained from the water transport simulation, N transport and transformation was modeled with Hydrus- 1D under different irrigation rates and different fertilization rates. Different soil texture scenarios were also simulated to demonstrate the influence of soil texture on N leaching. In the third study, the simulated N-leaching from different soil textures was integrated into a Geographic Information System (GIS) approach to estimate NO3-N leaching mass from urban turf areas. Nitrate-N leaching risks to ground water under overirrigation and overfertilization scenarios and efficient irrigation and fertilization scenarios were estimated. The results showed improvement of turf irrigation and fertilization management may decrease N-leaching significantly and greatly decrease the risk of ground water being contaminated by NO3-N leaching in the Salt Lake Valley.
153

A Study to Determine the Feasibility of Irrigating the Lands Included in the Cache Valley Water Conservation District No. 1

Jerman, I. Donald 01 May 1924 (has links)
The purpose of this report is to investigate the feasibility of irrigating the lands of the Cache Valley Water Conservation District No. 1. The district, as it now stands, is very much in need of many improvements. The Main canals are now in use and are in a good condition to serve all the lands with the required amount of water, but the few laterals that are now constructed, are in a poor condition, with the remaining laterals yet to be finished. Before successful irrigation can be practiced, a large portion of the land will require leveling and small areas are water-logged, which will require drainage. The soils of the area are of an impervious nature, and alkaline to some extent, which will require a definite method of procedure to put them in condition for plant growth. This report consists of a study of the factors affecting the feasibility of irrigating this district and includes a suggested program of reclamation.
154

Characterization and Monitoring of On-Farm Water Storage Systems in Porter Bayou Watershed, Mississippi

Kirmeyer, Richard Ludwig 14 December 2013 (has links)
The onarm water storage (OFWS) systems at Metcalf and Pitts farm in Porter Bayou Watershed were monitored for changes in nutrient levels and water withdrawal for irrigation from March 2012 to April 2013. Nitrogen and phosphorus levels were generally higher during the early part of the growing season. The OFWS systems can reduce nitrate and phosphorus in runoff up to 81% and 85%, respectively. However, the systems did not consistently reduce sediment and nutrients especially after significant rainfall and runoff events. The systems provided a total of 130 and 233 acreeet of recycled water for irrigating crops at Metcalf and Pitts, respectively, during the 2012 growing season. These amounts reflect significant savings in terms of groundwater. This study highlights the advantages of OFWS systems as structural BMPs to reduce nutrient loading into the Gulf of Mexico and to minimize groundwater withdrawals from the Mississippi Alluvial Aquifer.
155

The effect of sprinkler cooling on water conservation, house environment, and broiler performance

Moon, Jonathan W. 13 May 2022 (has links) (PDF)
Maintaining performance and mitigating heat stress of the modern broiler is a challenging task during hot weather conditions. Increased demand of high quality reasonably priced animal protein and predictions of future limited water availability make sustainability and water conservation a worthwhile goal for the poultry industry. The most used form for cooling broilers after wind speed is evaporative cool cell (CC) systems. Though highly effective at cooling the incoming air, they substantially increase the relative humidity inside the house, which hinders the bird’s ability to cool itself through evaporative respiration. Cool cells also utilize mass amounts of water. The objective of this research was to evaluate the effects of sprinkler technology on broiler performance, cooling water usage, inhouse environments, conservation, and sustainability, while providing information on how to successfully utilize sprinkler cooling in conjunction with an evaporative cool cell system.
156

Groundwater Crisis in Southern Rural India : Understanding Farmers’ Perspectives and Local Participatory Mitigation Strategies / Grundvattenkrisen i södra Indiens landsbygd : Förståelse av jordbrukares perspektiv och lokala anpassningsstrategier

Korlakunta, Rohini Srivyshnavi January 2022 (has links)
India is the largest user of groundwater in the world with an estimated utilization of 230 cubic kilometers per year which is over a quarter of the global total. More than 60% of irrigated agriculture is dependent on groundwater and when there is no adequate recharge of groundwater due to over exploitation and lesser rainfall, water scarcity and thus drought occurs. This study aims at proposing water conservation and management methods that are economically viable, socially acceptable, and practically possible in rural Indian farming landscapes which requires understanding the socio-economic and hydrogeological context of the region. The case of the village Pullalacheruvu is studied using surveys, focus group interviews, expert interviews, and field visits to understand the farmers’ perspectives and the local conditions. These results are then inferred to propose suitable water conservation and management methods. Based on the local context, ideas are proposed on how to implement these measures. It is noted that bringing awareness, community mobilization and building farm level infrastructure are important to achieve stable water availability in this region. Thus, this study acts as a reference for regions with similar hydrogeological and socio-economic contexts and also aids policy makers to understand the region.
157

The Proteomic Response of Northern Elephant Seal (<i>Mirounga Angustirostris</i>) Pups to Physiological Stress During Development

Voisinet, Melissa P 01 June 2019 (has links) (PDF)
Background: Northern elephant seals transition from terrestrial nursing pups to pelagic foraging juveniles in a short period of just 8-12 weeks. During the post-weaning period, pups rely solely on the energy reserves gained during nursing for their caloric demands and water supply. The prolonged absence of food after weaning is the first of many fasts for which the seals have evolved adaptations such as decreased urine production and increased blubber reserves. The stressors experienced from learning to dive for the first time are also stressors that they will experience frequently as an adult and for which they have evolved adaptations. The purpose of this study was to understand the tissue-specific molecular fasting- and diving- induced adaptive responses of pups during this critical transition. Methods: To investigate these adaptive responses to fasting and diving, we collected skeletal muscle and (inner and outer) adipose tissue from early-fasting (< 1 week post-weaning) and late-fasting (8 weeks post-weaning) pups. We analyzed the samples with mass-spectrometry-based proteomics using two-dimensional gel electrophoresis. Proteomics is an invaluable tool for analyzing marine mammal physiology, as it provides a large, unbiased data set of proteins that offer a comprehensive set of mechanisms involved with the cellular processes being studied. Proteomics has only been used as analytical tool for marine mammal biology in two other studies, and it can be used as a tool leading to the discovery of novel, unanticipated results. Results and Discussion: Because muscles are utilized during locomotion, we expected the proteome of skeletal muscle to highlight important physiological changes as the pups learn to dive. Inner adipose is more metabolically active than outer adipose, so we anticipated it would show important changes in metabolism throughout their fast. Outer adipose was useful to detect changes in the proteome due to thermoregulation, as it experiences the most drastic change in temperature and pressure while the pups learn to dive. In all tissues, we found significant shifts in energy metabolism proteins that show a decrease in lipid metabolism and urine production, and an increase in alternative metabolic pathways, such as the pentose phosphate pathway, which produces precursors for nucleic acid synthesis. We also found increases in cytoskeletal proteins, skeletal muscle proteins, and oxygen-binding proteins that facilitate the development of diving ability in late-fasting pups. Lastly, changes in the abundance of oxidative stress related proteins showed increased use of antioxidant proteins to control the production of reactive oxygen species in late-fasting pups. This study provides insight into cellular and physiological responses in marine mammals during ontogeny and their adaptive capacity during a key transition from a terrestrial to aquatic lifestyle.
158

COLLABORATIVE WATERSHED MANAGEMENT IN THE EAST FORK LITTLE MIAMI WATERSHED WITH AN EMPHASIS IN PLANNING AND PROJECT IMPLEMENTATION: AN INTERNSHIP WITH CLERMONT SOIL AND WATER CONSERVATION DISTRICT

McClatchey, Rebecca 26 May 2011 (has links)
No description available.
159

Promoting Domestic Water Conservation through the Utilization of a Scenario-Based Planning Support System

Burgess, Amy G. 22 July 2010 (has links)
No description available.
160

Development and Application of Policy-Based Tools for Institutional Green Buildings

Cupido, Anthony F. 04 1900 (has links)
<p><strong>Abstract</strong></p> <p>An opportunity exists to enhance policy development and application in higher education as it relates to the promotion of sustainable building practices and the application of Leadership in Energy and Environmental Design (LEED<sup>®</sup>) principles. No previous research has been conducted to determine if policy instruments are essential for sustainable building practices, together with the use of LEED<sup>®</sup>, for the implementation of institutional green buildings in North America.</p> <p>The primary research goal is to determine if policy is essential for sustainable building practices and the implementation of LEED<sup>®</sup> for new construction and major renovations in higher education buildings in Canada and the United States. A specific focus on water conservation and water quality is undertaken related to green buildings. A comprehensive quantitative web-based survey was developed and administered to poll members of APPA (formerly the Association of Physical Plant Administrators) on their use of policies or other instruments for sustainable development and the specific use of LEED<sup>® </sup>applications for new construction and major renovations on their campuses. Qualitative telephone interviews were conducted with a subset of the survey respondents to explore and supplement components of the survey and to gain greater insight as to the strategic application of sustainable facility initiatives at their respective institutions. A sustainable building policy template is developed for application to the higher education sector.</p> <p>Using a mixed-methods approach has provided clear evidence that these institutions are contributing to the growth in sustainable practices in higher education and that the facility professionals are contributing to much needed leadership in this field. Institutions that have implemented sustainable/green building policies for their new buildings or major renovations are exhibiting policy compliance and meeting their LEED<sup>®</sup> targets, while some institutions that utilize non-policy practices are not complying.</p> <p>This research provides a framework for an institutional sustainable building policy that is suitable for use as a template for senior facility professionals and their specific policy development. This work contributes to a foundation for future research related to sustainable/green building policy development and its application to the higher education sector.</p> <p>A review of survey participants’ water conservation approaches was undertaken with a specific application to a rainwater harvesting-to-potable water system in the Engineering Technology Building (ETB) at McMaster University. <strong></strong>Field research was undertaken on the evaluation of three white roof membranes: modified bitumen finish ply, polyvinylchloride (PVC), and thermoplastic polyolefin (TPO); and their effects on the runoff water quality were studied. An analysis of the quality of rainwater runoff was performed from each of these three membranes and compared to Ontario provincial drinking water standards. Analyses were performed to determine if there is a preferred membrane for this function.</p> <p>Results of the water quality testing and analysis indicate that the selected white roof membranes will provide a suitable catchment surface for a green building and/or use in a rainwater collection system. When compared to Ontario’s MOE water quality requirements, no particular roof membrane of the three researched (modified bitumen, PVC and TPO) provided superior water quality results to suggest that either was preferred or recommended as a rainwater harvesting (RWH) catchment surface.</p> <p>This research has revealed that higher education institutions are engaging in water conservation practices across Canada and the United States. Operational challenges are evident, particularly as they relate to waterless urinals. The ETB system that harvests rainwater and provides treatment to potable standards is showing significant promise for future site–based solutions.</p> / Doctor of Philosophy (PhD)

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