• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1237
  • 844
  • 180
  • 156
  • 103
  • 16
  • 11
  • 9
  • 8
  • 7
  • 6
  • 6
  • 6
  • 6
  • 6
  • Tagged with
  • 3018
  • 1001
  • 605
  • 461
  • 339
  • 283
  • 274
  • 267
  • 238
  • 205
  • 195
  • 189
  • 187
  • 184
  • 168
  • 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.
81

FACTORS AFFECTING STAKEHOLDER PERCEPTIONS AND INFLUENCE ON MANAGEMENT AGENDAS WITHIN THE TISZA (CENTRAL EUROPE) AND MISSISSIPPI RIVER BASINS (U.S.A.)

Marshall, Amanda Christine 01 May 2017 (has links)
Stakeholder engagement and collaborative governance have become increasingly important in the field of river basin management. Modern basin management strategies tend to take an adaptive or integrative management approach, which call for broad stakeholder inclusion to account for the increasing uncertainty and competing demands placed on water resources. This dissertation examines several key aspects of stakeholder participation: public awareness and value of participation in management, opportunities and barriers to participation, and the effect of public participation on watershed management outcomes. A major goal of this project is to identify factors that enhance managers’ ability to include effective stakeholder participation in the water governance process. While opportunities for participation are increasingly mandated as part of environmental management practices, the quality of that participation is often called into question. In the first of three papers comprising this dissertation, I conducted an interdisciplinary study assessing risk perception and actual health risks from exposure to metals in fish from the Tisza River Basin of central Europe. Mining in the region has chronically introduced metals; however, two major mine-tailings spill in 2000 contributed an estimated 240,000 m3 of wastewater and tailings contaminated with cyanide and metals to the system. In 2013 and 2014, water and fish (N=99) collected from the lower Tisza River Basin were analyzed for cadmium, copper, lead, nickel, and zinc. Concurrently, surveys (N=45) collected near sampling sites assessed fish consumption patterns and risk perception. Metals in water exceeded regulatory criteria at multiple sites, however metals are not bioaccumulating to a concerning degree in fish as bioaccumulation factors were below 1. Fillets were within European Food Safety Authority recommendations; however, the Target Hazard Quotient for lead was elevated at 1.5 for average consumers and 3.5 for people who consume fish twice weekly. The majority of survey participants were unconcerned with local fish consumption (87%), citing the “clean” appearance of fishing locations. Participants also reported relatively low fish consumption, with most (76%) eating basin fish once a week or less. While our study indicates fish are generally safe for human consumption, waters are polluted, suggesting that local fishing populations may be at risk from unseen pollutants and highlighting the need for monitoring and notification systems. Broadening the analysis of local stakeholders and stakeholder perception to the basin level, the second paper for this dissertation examined public perception and public participation in Tisza River Basin management. The complexity associated with achieving sustainable river basin management plans for international, transboundary river basins, such as the Tisza River Basin in central Europe, make them an ideal study area for examining the influence of education and experience on stakeholder perception of basin management. This study presents findings from analysis of in-person surveys to examine differences in local stakeholder perceptions of the Tisza River Basin across employment and education sectors through analysis of participants’ levels of knowledge, experience, and involvement in basin management. The survey was conducted among members of the public in locations across the basin, in which participants were asked to identify and rank their opinions of factors affecting the health of the river basin, to identify observed changes in flood patterns, and to rank their level of interest and participation in basin management activities. To evaluate whether experience affected responses, participants were grouped according to whether they worked in the public or private sector, and by their level of education (no college, undergraduate, or graduate school). Significant differences in stakeholder responses were found between education levels attained among participants in the public versus the private sector, and between the reported levels of environmental concern among participants of different education levels. Participants also reported low levels of participation and monitoring of management activities. These differences and lack of participation highlight the need for public education in participatory governance structures to support sustainable river basin management efforts. The Upper Mississippi River Basin is similar to the Tisza River Basin in its transboundary nature and the predominance of agriculture in the region. The Upper Mississippi River Basin (UMRB) is a largely rural watershed (Minnesota, Wisconsin, Iowa, Illinois, and Missouri) that is heavily managed for agriculture and agricultural exports. This has led to water quality impairments both within the Upper Mississippi River Basin and contributed significantly to the large hypoxic zone of the Gulf of Mexico. Management responses have led to the formation of collaborative responses across stakeholder groups, including states, agencies, industry, non-government organizations, and the public. In the third paper of this dissertation, I shifted my focus from the public to another set of local stakeholders, environmental non-government organizations (ENGOs), and their influence on river basin management. ENGOs are recognized as serving as implementers, catalysts, and partners with government agencies in the management process. To assess the participatory role of ENGOs in watershed management in the Upper Mississippi River Basin, expert interviews were conducted with members actively engaged in watershed-related activities. Participants were asked to identify their key areas of
82

Programa Estadual de Microbacias Hidrográficas: Análise das Ações Implantadas na Microbacia do Córrego Ariranha no Município de Junqueirópolis (SP)

Brigatti, Adriana Secco [UNESP] 15 December 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-12-15Bitstream added on 2014-06-13T18:46:46Z : No. of bitstreams: 1 brigatti_as_dr_ilha.pdf: 1148993 bytes, checksum: 05f5bc59d122e015687294b7b7e7c76e (MD5) / Universidade Estadual Paulista (UNESP) / Considerando a importância do Programa Estadual de Microbacias Hidrográficas implantado no Estado de São Paulo entre os anos de 2000 a 2008, este trabalho objetivou avaliar as ações implantadas pelo referido Programa na microbacia do Córrego Ariranha, localizada no município de Junqueirópolis (SP). A questão a ser respondida seria em que medida esses ações teriam contribuído para desencadear um processo de desenvolvimento sustentável? Para obtenção dos dados foram aplicados questionários e realizadas entrevistas com os produtores rurais da microbacia estudada e com os gestores do programa, abordando as subvenções obtidas e o atendimento às expectativas geradas pelo PEMH. A base econômica desses produtores está centrada na pecuária de leite/corte e na fruticultura, especificamente na produção de acerola, além da cana, café e seringueira. As subvenções obtidas através do PEMH nessa microbacia totalizaram R$ 405.372,04, destacando os abastecedouros comunitários, construção de terraços e calagem. Com relação à avaliação os produtores consideram que o programa atendeu suas expectativas, possibilitou melhoria da renda das famílias, e atendeu às necessidades da comunidade da microbacia e, dentre as ações implantadas, a mais relevante foi a que construção de 11 abastecedouros comunitários que possibilitou disponibilidade de água nas propriedades resultando em melhoria na qualidade de vida dessas famílias. Questões ambientais, como a proteção de Área de Preservação Permanente, não foram priorizadas pelos produtores, alegando perdas de áreas para o setor produtivo. O tempo destinado para a implantação das ações (5 anos) em função da microbacia ter sido a terceira trabalhada no município, foi o maior problema apontado pelos produtores... / Taking into consideration the importance of the program Micro Basin State Program - Phase I (PEMH) set up in the State of São Paulo between 2000 and 2008, the present dissertation aimed at evaluating the actions taken by the mentioned program in the micro basin of the Ariranha Stream, in Junqueirópolis, SP, Brazil. The goal is to know whether the actions taken would have contributed to establish a process of sustainable development. Surveys and interviews with local producers and the program’s managers were applied to obtain the data, addressing the achieved grants and the fulfillment of the generated expectations of the PEMH. The economic base of local producers is mainly stock raising and fruit growing, specially acerola, along with sugar cane, coffe beans and rubber trees. Subsidies obtained through the PEMH in this micro basin added R$ 405.372,04, including the collective water suppliers, terraces building and liming of the soil. The producers consider that the program satisfied their expectations, meeting their community needs and allowing an increase in their family income, specially the construction of 11 collective water suppliers that made water available to their properties and enhanced their quality of life. Environmental issues, as the protection of Areas of Permanent Preservation (APP’s), were not prioritized by the producers that claimed such initiative reduced their available productive land. Since their community was the third to have the program implemented, the major problem pointed by them was that it took too long (5 years) for them to access its benefits. According to the executives of the PEMH, the actions taken were specific, and yet accomplished an increase in the quality of life of the rural families, therefore should not have been interrupted. Despite the limitations and... (Complete abstract click electronic access below)
83

Sulphur solubility behaviour in evolved magmas : an experimental study

Moncrieff, Duncan Hunter Sadleir January 2000 (has links)
A relationship between the sulphur valence of a melt and f 02 has been determined. The relationship has been used to determine the f O2 conditions under which melt inclusions were trapped in andesitic magmas before magma mixing, and of a slowly cooled pyroclastic flow in which Fe-Ti oxide phases have re-equilibrated. The results help distinguish two trends in lavas from Lascar Volcano: In one, the melt fO2 is buffered by iron redox ratio, while in the other f02 is buffered by S02-H2S in a comagmatic vapour phase. The behaviour of sulphur was experimentally investigated in hydrous phonolitic and rhyolitic melt at 930 °C and 0.5 to 4 kbar. Pyrrhotite is stable under reducing conditions in both melts, and immiscible FeS sulphide liquid is stable under certain conditions of pressure and f S2 at 5 log units above the Ni-NiO buffer. Anhydrite and Srich sodalite are the usual magmatic S-bearing phase under oxidising conditions in rhyolitic and phonolitic melts respectfully. Melt sulphur content is positively correlated with f 02 and f S2. pressure has no significant effect for the conditions investigated. A thermodynamic model has been derived that successfully reproduces the results of this study and of a previous study. The partitioning of sulphur between vapour and melt is a function of f 02, f SZ, phase stabilities and mass balance constraints. Sulphur solubilities and f02 were determined for a suite of back arc basin basalts (BABB). The BABB samples follow two trends: those with low values of f02 have high S contents, whereas more oxidised samples have lower sulphur contents. The solubility behaviour can be described by sulphide-sulphate melt-vapour equilibria. The f02 of the oxidised samples implies that subducted material was incorporated into their magmatic source, a hypothesis supported by major and trace element studies of the samples
84

Planning for balanced social, economic and physical development : Ghana Volta basin.

Kudiabor, Clemence Degboe Kwashivi January 1963 (has links)
Regional planning, as an approach to development planning, in the newly independent nations of the world, is the main subject of this study. The purpose of the study is to demonstrate the hypothesis that to achieve a balanced social, economic and physical development the scale of planning must be regional. Since the region is the link between the national and local community, it provides a suitable frame of reference for the balanced integration of both national and local projects. The Volta Basin in the Republic of Ghana in West Africa, is taken as an illustrative case study. The case study focuses attention on the methods used in designing the Volta Basin Regional Plan. The Plan is meant to demonstrate how regional planning can help towards balanced development by giving due consideration simultaneously to all the factors involved in the development process. The approach taken in the study was, first, to discuss the problem in a general way by analyzing the main features of development planning as currently practised in a number of the newly independent nations. The conclusions drawn from this discussion are that: 1) the major problem of most of the new nations is that of a single-resource economy inherited from their former colonial rulers; 2) the approach to development planning as currently practised in these countries takes the form of National Development Plan and tends to concentrate solely on the economic aspects of development and, to some extent, the social aspects, and ignores the physical aspects of development; 3) while development planning is increasingly becoming the function of Central Governments, the tendency is to be concerned with planning at the national level with no regard for development at the regional and local levels; 4) in those countries where some effort is made in terms of regional planning for development, the approach that is adopted is in the form of either multi-purpose river basin development or the strictly economic regional development. As a result of these shortcomings of current development planning in the newly independent nations, it is further concluded that the failure to give due consideration to all the factors involved in the development process, gives rise to imbalanced development in these countries. The imbalanced development takes the form of excessive concentration of population in a few urban centers which are usually piled up with poor untrained labour from the rural areas. The urban centers are notorious for all forms of social disorganization: crime, overcrowding, unemployment, and other social problems. The unbalanced development also takes the form of unplanned distribution of industry and rural services, and poor location of transportation routes, resulting in expensive remedial measures. The defects of current development planning in the new nations seem to be a result of the conception of the nature of development, namely that development is essentially an economic problem and once the economic factor is considered, the other factors involved will take care of themselves. It seems also that the economic conception of the nature of development is a result of the influence and advice of the specialists interested in the problems of development of these countries. A new conception of development that takes into account the social, economic, cultural, psychological and physical components of the entire society, leads to the view that planning for development must be regional. This is because regional planning considers simultaneously all the factors involved in the development process. The study discusses development planning in Ghana in order to outline the main problems of development in Ghana and to provide the background for the consideration of the regional planning needs of the country. As in the case of the other newly independent nations, it is con eluded from the discussion that Ghana inherited a single-resource economy; its approach to development planning is restricted to planning at the national level with no regard for the implications of development at the regional and local levels; and that planning for development is regarded solely as an economic problem. As a result of these facts, it is further concluded that Ghana fails to achieve a balanced development—throughout the country. This leads to an analysis of the Volta Basin Regional Plan to demonstrate how regional planning can help towards the achievement of balanced development by giving due consideration to all factors involved in the development process. Based on the simultaneous consideration of the social, economic and physical factors, it is possible to make proposals that reflect the needs of Ghana in terms of the distribution of population and industry; the location of the main transportation routes; the distribution of rural services and the location of large non-agricultural uses. The following proposals are made to introduce the planning process of survey, analysis, plan, implementation and revaluation, into the regions of Ghana: 1) expanded National Planning Commission; 2) expanded Regional Planning Agencies, and 3) regional plans for the eight Administrative regions of Ghana. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
85

Precipitation of the Fraser River basin : a descriptive study.

Wallis, John Hubert January 1963 (has links)
This study of precipitation is based on data in the 1955 Climate of British Columbia concerning the network of 106 stations which have been operated in the Fraser River Basin, Emphasis is on the description of precipitation characteristics, with cartographic representation of the data forming the basis of the explanations and discussion in the The first portion of the study concerns the concentration of annual and seasonal precipitation throughout the Basin, followed by a similar examination of mean annual and seasonal snowfall with observations concerning the proportion of annual snowfall in each season and the proportion of seasonal precipitation which occurs as snow. A parallel discussion of proportions for total precipitation, with emphasis on seasons and months of maximum and minimum, is concluded by an analysis of precipitation regimes in various parts of the Basin. The effect of the gaps in the Coast Mountains resulting in continental or coastal characteristics of precipitation, dependent on station location, is noted repeatedly throughout the thesis. Considerations of variability as well as the value and methods of checking homogeneity of station records are included with observations concerning years in which heavy or light precipitation was general in large parts of the Basin. An examination of all topics as they affect the thirteen sub-basins of the Fraser concludes the study. / Arts, Faculty of / Geography, Department of / Graduate
86

A cultural geography of northern Foxe Basin, N.W.T.

Crowe, Keith Jeffray January 1969 (has links)
The shallow post glacial sea of northern Foxe Basin contains a large walrus herd. Complemented by other game resources, the herd has supported human settlement for about four thousand years. During sequent occupance of the region by different prehistoric hunting cultures there was adaptation to changes in climate, game resources and land forms. Despite variations in environment, there was remarkable continuity in the coastal settlement pattern. From a "core" area of relatively dense and permanent settlement, concentric areas decreased in viability towards the regional margins, where adverse ice conditions were a major deterrent to settlement. Whaling fleets visited the regions adjacent to northern Foxe Basin from about 1840 to 1910. Although the region itself was barred to whaling ships by pack ice, the whole Melville-Borden culture territory, including northern Foxe Basin, suffered from the social and ecological disequilibrium caused by whaling activity. At the end of the whaling era the rifle and whaleboat had been added to the hunting technology, but the population of the region was reduced. In the 1930's the establishment of a mission and later a trading post in the core area brought new focus to settlement in the region. Immigration from neighbouring regions, and natural increase in the population resulted in expansion of settlement. Following a period of experimentation, population distribution stabilized in a series of contiguous areas, each supporting an ecological and economic unit. The trapping and hunting settlement of the "camp system" adhered closely to the ancient regional pattern. Although the camp system appeared to be a return to the prehistoric subsistence equilibrium, technological innovation threatened the game resources, and the proceeds of fur sales could not meet the consumer demand of a growing population. The construction of defence establishments, commencing in 1955, broke the long isolation of northern Foxe Basin. Government activity in the region increased through the 1960's and subsidy became the economic base of the region. In 1966 the federal government introduced a large-scale rental housing scheme, which precipitated the collapse of the hunting settlement system. Igloolik and Hall Beach changed from being service centres serving dispersed regional settlements, to nodal centres of tutelage, containing almost the entire population of the region. The Iglulingmiut Eskimos entered a radically different phase of social and economic transition, and are now attempting to work out a compromise between traditional and superimposed social forms. The Iglulingmiut, in the relative isolation of their region, have been able to absorb change slowly, until recently. Their sense of identity, their symbiotically-based social structure and hunting tradition are sources of strength and pride. Compared to many other Eskimo groups they appear well prepared to meet future changes. Much will depend, however, on the willingness of government planners to build upon existing cultural foundations, and to proceed at a pace which permits Eskimo participation. / Arts, Faculty of / Geography, Department of / Graduate
87

Geological setting and surficial sediments of Fatty Basin, a shallow inlet on the west coast of Vancouver Island, British Columbia.

Wiese, Wolfgang January 1971 (has links)
Fatty Basin and Useless Inlet result from modification by water and ice erosion of depressions caused by Early Tertiary faulting. Uplift of the land due to post-glacial rebound is in excess of 6 m (20 ft) for the last 7000 years. Shallow entrance sills cause the inlets to act as traps for organic detritus brought in by tidal action. The rate of deposition of fine-grained suspended debris is in the range of 900 g/m² /year, with maximum deposition during late summer, when phytodetritus is most abundant. Five sedimentary environments exist in Fatty Basin, namely mud zones, rock slopes, beaches, deltas, and zones of strong currents. In addition to boulder accumulations and bedrock exposures, general categories of sediments are pebbles and gravels, terrestrial sands, shell debris, muds, and shell-gravel mixtures. Statistical analysis of the size distribution of 125 samples resulted in recognition of 8 groups of sediments, which were then subdivided into 13 types on the basis of composition and grain shape. Olive-green mud rich in organic matter covers almost three-quarters of the bottom surface in the Basin. Coarse terrestrial sands are derived mainly from bedrock exposures within about 300 ft of the shore, whereas most of the fine sands, silts, and clays originate from glacial sediments. The source area for glacial debris is in the Henderson Lake region, underlain dominantly by Karmutsen basalts. Shell debris, notably barnacle plates and calcareous worm tubes, is essentially confined to the rock-slope environment, where it accumulates in a narrow zone along the base of steep slopes. The rock-slope environment represents a preferred habitat for lobsters, because it offers better shelter and food supply than the other environments. In Fatty Basin, the total area most suitable to lobsters amounts to about 38,000 m² (=7% of the bottom surface), in Useless Inlet, this area covers 135,000 m² (= 5% of the bottom surface). / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
88

Testing for a Functional Relationship Between Shell Rings and Flood-Prone Environments in the Yazoo Basin of the Lower Mississippi Alluvial Valley

Raymond, Tiffany Renee 12 August 2016 (has links)
The form and function of freshwater mussel shell rings in the Yazoo Basin was examined in this thesis. General and controlled surface collections, excavations, a seriation, and documentary research on flooding in the Yazoo Basin were completed. Four sites were investigated, including 22YZ513 (Rugby Farm), 22YZ605 (Light Capp), 22QU562 (Devil’s Race Track), and 22QU569 (Drew Smith), in an attempt to address whether shell rings were a functional byproduct of flood-prone environments. Results indicated that the two Quitman County sites were not shell rings, even though they appeared as such from aerial photographs, and that they represent a different ceramic cultural lineage than the two shell ring sites in Yazoo County. The two shell ring sites support hypothesis 1: that a functional relationship existed between shell rings and flood-prone environments during the Middle to Late Woodland periods in the Yazoo Basin.
89

Thermal and Diagenetic Evolution of Carboniferous Sandstones, Central Appalachian Basin

Reed, Jason Scott 25 April 2003 (has links)
The thermal and diagenetic evolution of Carboniferous sandstones in the central Appalachian basin has been resolved using various techniques. Paleothermometers including vitrinite reflectance and fluid inclusions indicate that burial of Lower and Upper Pennsylvanian strata of the Appalachian Plateau in West Virginia exceeded 4.4 km during the late Permian and occurred at a rate of ~100 m/m.y. Exhumation rates of ~10-30 m/m.y. from maximum burial to present depth were constrained using published apatite fission track and radiogenic helium ages. Quartz, lithic and feldspar-rich sandstones from different stratigraphic intervals and locations were sampled from core (95 %) and outcrop (5%) to qualitatively and quantitatively evaluate sandstone diagenesis. A compositional multivariate data set compiled from point counts served as the basis for quantitative analysis of controls on sandstone diagenesis such as framework grain composition, paleoclimate and depositional environment. A priori groups (independent variables) corresponding to the controls were compared using digenetic products (dependent variables). Major conclusions of the analysis are, first, minerals that formed early appear to have been influenced by stratigraphic position. The distribution of siderite and iron-oxide/oxyhydroxide may reflect the second order paleoclimatic signature recognized throughout the Carboniferous, where siderite formed during everwet periods and iron-oxide/oxyhydroxide during semi-arid conditions, reflecting differences in redox. Second, framework grain composition controlled the distribution of diagenetic alterations and quartz cementation in the burial environment. Lithic arenites are deficient in authigenic quartz, yet have undergone various degrees of illitization. The quartz deficiency is attributed to compaction-related loss of primary porosity relatively early, which inhibited flow of silica-bearing fluids. Finally, no correlation can be demonstrated between depositional environment and diagenesis. Anomalously high fluid inclusion homogenization temperatures (> 215 °C) from Upper Pennsylvanian sandstones adjacent to the Alleghany Thrust Front indicate that tectonic setting played an important role in quartz authigenesis. The discrepancy between the fluid inclusion and vitrinite reflectance data imply that warm silica-bearing fluids, likely sourced from low-grade metamorphic reactions, were injected into Pennsylvanian sandstone aquifers during thrust loading associated with the Alleghanian orogeny. / Ph. D.
90

Hydrochemical facies study of ground water in the Tucson Basin

Smoor, Peter Bernard. January 1967 (has links)
The concept of hydrochemical facies is used to study the distribution and, indirectly, to identify the origin of the chemical character of ground water in the basin-fill aquifer of the Tucson Basin in relationship to the hydrogeologic framework. Hydrochemical fades of ground water is defined operationally in terms of the lateral (horizontal) variation of chemical quality. The following chemical constituents are included in this study: total dissolved solids, calcium, magnesium, sodium, potassium, chloride, sulfate, bicarbonate, pH, nitrate, fluoride, strontium and zinc. A conceptual process-response model relates the regional distribution of dissolved constituents to the following hydrogeologic controls: (a) the chemical composition of the rock and soil in the drainage area before recharge to the ground-water basin and conditions at the recharge sites, (b) the lithology of the basin-fill aquifer, and (c) the direction of groundwater flow within the aquifer itself. Trend surface analysis suggests that the regional distribution patterns of total dissolved solids, calcium, sodium, sulfate and strontium show a tendency to parallel the direction of ground-water flow. The distribution pattern of chloride ions based on old analyses shows a trend opposite to the distribution pattern of chloride ions based on new analyses from the same area. Nitrate content of ground water and specific capacity of wells seem to be related. Q-factor analysis of data from the basin-fill aquifer demonstrates that the overall chemical character of the ground water does not change substantially as it moves through the basin. It is concluded that the chemical character of ground water in the basin-fill aquifer of the Tucson Basin was acquired mainly during contact with various rock types in the drainage basin before recharge. The lithology of the aquifer, presumably, only plays a secondary role in determining the overall chemical composition of the ground water. After recharge to the basin-fill aquifer the distribution of dissolved constituents is controlled primarily by the flow pattern. A chemical equilibrium model of calcite and water is used to approach the problem of determining whether precipitation or dissolution of calcite takes place in the aquifer. Measured calcium ion concentrations and pH values are compared to calcium ion concentrations and pH values computed for the equilibrium model. Assuming that the equilibrium model represents actual conditions in the aquifer, departures from the equilibrium model may be used to predict the chemical behaviour of calcite In the basin-fill aquifer.

Page generated in 0.0302 seconds