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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.
211

Indigenous communities and the co-management of natural resources : the case of New Zealand freshwater management

Tipa, Gail, n/a January 2003 (has links)
The starting point for this study is a socially constructed problem: the progressive degradation of natural resources of significance to indigenous communities and the lack of effective participation by indigenous communities in their management. For many indigenous communities survival was traditionally dependent upon knowledge of natural resources and the ability to gather sustainability those resources from lands, waterbodies and the seas within tribal territories. Environmental sustainability and the long term wellbeing of indigenous communities were seen as one and the same thing. But following contact with exogenous groups, and until relatively recently, indigenous perspectives on environmental management were largely ignored. Dispute over ownership, access to management and use of natural resources have been sources of long standing grievance for indigenous communities throughout the world including Maori within New Zealand. In the last decade co-management has been promoted as a means of ensuring the participation of indigenous communities in contemporary resource management. But what is meant by co-management has been less clear. This thesis posits that of the four possible definitions of co-management - namely dual management, cooperative management, collagorative management and community based management - it is collaborative management that promises the greatest benefits for indigenous populations and the environment alike. An analytical framework is developed which acknowledges the theories brought to such collaboration by State agencies and Maori in New Zealand. A case example is then presented of the establishment of a collaborative management programme involving freshwater in the Taieri Catchment near Dunedin. Experience of this case suggests that in addition to affirming progressively validated general principles governing collaborative environmental management, the requirement for trusted facilitators acting at the interface between State agency and indigenous groups is mandatory. It is concluded that the potential exists for the collaborative management of environmental resources by State and Maori in New Zealand but that the process has barely begun and requires investment in capacity building on the part of both parties.
212

Characterization of nutrient and suspended sediment concentrations in stormwater runoff in the Lake Tahoe basin

Gunter, Melissa K. January 2005 (has links)
Thesis (M.S.)--University of Nevada, Reno, 2005. / "May, 2005." Includes bibliographical references. Online version available on the World Wide Web.
213

Analysis of streamflow variability in Oregon for regional water quality monitoring programs

Saligoe-Simmel, Julia L. 27 October 1997 (has links)
Streamflow variability can provide valuable information for nonpoint source pollution monitoring program planning. The research papers presented in this thesis examine selected properties of streamflow variability in Oregon to advance its application in regional planning of water quality monitoring programs. The products of this research depict Oregon streams by their relative streamflow variability and evaluate factors that may influence that variability. The three manuscripts examine the application of streamflow variability in the context of regional strategic planning by addressing three related questions: 1.) What is the relationship in Oregon between streamflow variability and watershed size, which is often described as a proxy for streamflow variability?, 2.) What geographic factors in Oregon influence streamflow variability, and are regionalscale factors adequate to efficiently predict streamflow variability on ungaged streams?, and 3.) How is streamflow variability in Oregon affected by seasonal climatic variation? Examination of these questions regarding the behavior of streamflow variability of river systems in Oregon is used to assist in the design of regional and local water quality monitoring programs. Data are from historical records of established US Geological Survey gaging stations. Simple linear regression depicts the relationship of streamflow variability to basin size on a statewide basis and stratified by ecoregions. The results indicate that basin area is not an appropriate indicator of streamflow variability. Multiple regression is used to develop regional models of streamflow variability. Three models are developed for natural flow streams and streams with upstream diversions. Regional and watershed scale variables are evaluated for their potential contributions to the models. Watershed scale variables do not increase the predictive capacity of the models; therefore, the regional scale is appropriate for efficiently modeling streamflow variability. Seasonal investigation of streamflow variability in Oregon develops its application for seasonal monitoring programs. Spatial and temporal analysis reveal a weak relationship between annual and monthly streamflow variability, indicating potential for refined application of the variability index. Streamflow variability is an accessible tool for developing water quality monitoring programs. The regional scale distribution of streamflow variability in Oregon demonstrates the ease at which streamflow variability may be estimated on ungaged streams. / Graduation date: 1998
214

Flow characteristics of constructed wetlands : tracer studies of the hydraulic regime

Stairs, Darrin B. 28 July 1993 (has links)
Treatment efficiency in a constructed wetland is related in part to the amount of time that a wastewater remains in the system. Current design methods idealize the system as a plug flow reactor and use a "residence time" based solely on the volume of the cell and the flow rate. Under this assumption, every element of wastewater entering the wetland cell experiences the same residence time. It is understood that this idealization ignores the existence of longitudinal dispersion, short circuiting and stagnant regions within the wetland cell. The result of these phenomena is a distribution of residence times. In other words, portions of the effluent exit the cell earlier than predicted, resulting in undertreatment, and portions exit late, resulting in excess treatment. The average concentration of treated wastewater at the outlet is a function of this distribution and the reaction kinetics associated with the waste. The overall effect of a distribution of residence times is reflected in a reduction of treatment efficiency at the outlet. Hydraulic regimes of constructed wetland systems were investigated at a pilot project site providing tertiary treatment of a pulp mill wastewater. Two vegetation types, bulrush and cattail, were investigated and compared to nonvegetated and rock-filter cells with identical configurations. Tracer studies used a fluorescent dye and were performed over the course of a year. Dye was input as a pulse at the inlet end of the cell and sampled over time at the outlet end to obtain concentration breakthrough curves. From these curves, time to peak, actual mean detention times, degree of dispersion, and extent of dead space were calculated, as well as predicted treatment efficiency. Results indicated varying degrees of dispersion, short circuiting, and dead space in the individual cells. Analysis of the residence time distributions provided estimates of the "active" volume of the treatment cell and the degree of short circuiting in the system. Effective volume of the planted cells ranged from 15 to 25% of full volume. Early arrivals of the peaks of the distributions, indicative of short circuiting, ranged from 30% to 80% of the theoretical detention times. A first order treatment model and a kinetic coefficient, k, were assumed, and corresponding treatment efficiencies were compared to the theoretical treatment of an ideal plug flow reactor. Reduced treatment efficiencies for the planted systems ranged from 2 to 20 %, by this estimation. Many references attempt to analyze wastewater treatment systems by refering to two models: dispersed plug flow and an approximation of tank-in-series. These models were investigated as potential descriptions of the hydraulic regime present in constructed wetlands. Residence time distributions of the constructed wetlands in this study indicated flow was not exclusively dispersed plug flow. This simplified model does not account for the exchange of material with "dead" space in the wetland cell. The data suggest a combination model of dispersed plug flow with a transient storage zone component may be more appropriate. / Graduation date: 1994
215

A Novel Pervious Cement Reaction Barrier (PCRB) <i>in Situ</i> Arsenic Remediation System

Jones, Morgan Liane 01 May 2010 (has links)
No description available.
216

A spatial optimization approach to watershed water quality management a case of the Opequon watershed /

Karigomba, Wilbert. January 2009 (has links)
Thesis (Ph. D.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains ix, 199 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 142-172).
217

Water resources decision making using meta-heuristic optimization methods

Eusuff, Muzaffar M. January 2004 (has links)
This dissertation work is part of a larger research effort involving soil-aquifer treatment (SAT). The dissertation's focus was to investigate meta-heuristic (global) optimization methods suitable for developing water resources decision support system (DSS), particularly to optimally design and operate groundwater storage and recovery projects. The effort included developing an integrated simulation-optimization management model for complex aquifer recharge/extraction operation considering water quality transformation. The research demonstrated successful integration of three-dimensional hydraulic, water quality, and particle tracking models with shuffled complex evolution (SCE) optimization algorithm. It also included developing the shuffled frog leaping algorithm (SFLA), a meta-heuristic optimization technique for solving discrete/combinatorial problems, and its application to aid decision making in water supply and distribution system optimization issues. SFLA is a memetic, meta-heuristic population-based cooperative search metaphor inspired by natural memetics. SFLA was developed by extending the logic of two existing global optimization techniques for continuous optimization problems. The local search is completed using an extension of the particle swami optimization (PSO) method, and the global exploration is performed by a technique similar to that used in the shuffled complex evolution (SCE) algorithm. SFLA was tested favorably on several literature test functions and engineering problems that present difficulties to many global optimization problems. The effectiveness and suitability of this algorithm has also been demonstrated by applying it to a groundwater model calibration problem and several water distribution system design problems that are considered as benchmark problems in the literature. The comparison of SFLA with other existing global optimization methods, such as genetic algorithms (GA), in terms of the likelihood and efficiency of converging to a global optimal solution, suggests that SFLA can be an effective algorithm for solving discrete/combinatorial optimization problems.
218

The use of bacteria to monitor and reflect pollution of the aquatic environment

Chiu, Hok-cheung, Simon., 周鶴祥. January 1992 (has links)
published_or_final_version / Botany / Master / Master of Philosophy
219

COMPLIANCE DECISION-MAKING: THE CASE OF WATER POLLUTION IN OMAHA, NEBRASKA

Ball, Bruce Porter, 1946- January 1974 (has links)
No description available.
220

Nonpoint Source Pollution: A Report on Tasks 5321, 5327, and 5332

University of Arizona. Water Resources Research Center., University of Arizona. College of Agriculture., Pima Association of Governments, 208 Project. 11 1900 (has links)
Pima Association of Governments 208 Project / Nonpoint Source Pollution, A Report on Tasks 5321, 5327, and 5332 / Prepared by: Water Resources Research Center and College of Agriculture / The University of Arizona, November 1977

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