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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.
221

Endocrine disruption in wild populations of three-spined sticklebacks {Gasterosteus aculeatus) from English rivers

de Assuncao, Marta Goncalves Leite January 2009 (has links)
No description available.
222

An examination of the adoption and implementation of human centred approaches in Malawi's conservation policies and regulatory frameworks

Mawaya, Chimwemwe Roberta Mhango January 2008 (has links)
No description available.
223

How the environmental movement influenced climate change debates in Britain between 1986 and 2008

Price, Stephan January 2012 (has links)
This thesis examines the influence of environmental movement actors on press coverage about climate change between 1986 and 2008. It assesses the extent to which social dynamics that resemble Habermas' ideal of communicative action are important for frequent and significant impacts on media coverage. The thesis is based on four strands of research: interviews, Internet- and literature-sourced material to build a description of the British environmental movement; frequency counts of climate change coverage across four UK national newspapers; a frame analysis of a 1000+ article sample of this coverage; and background research into the political and media contexts of the climate change issue, involving further interviews and textual sources. High profile political interventions before 1992 cemented a pattern of media coverage that privileged government, science, and business over the environmental movement. Thus, although the amount of climate change coverage increased, the proportion of climate change-related coverage that referred to environmental movement groups did not keep pace. Instead, the most significant influence was political. The UK government's adoption of a target of 80% reductions in carbon emissions by 2050 followed a period of intense movement activity on climate change in which radical, reformist, and conservationist organisations were often well-networked, while reflecting different relationships with 'grass-roots' actors. Formal organisations, such as Greenpeace, Friends of the Earth and RSPB regularly and routinely made press releases, but these were associated with declines in news coverage more frequently than increases. The introduction of new relationships, actors, or pen;;pectives, such as the creation of Stop Climate Chaos and the Climate Camp, or senior politicians' support for legislation on climate, tended to be associated with the most significant positive impacts upon newspaper coverage. Interactions between environmental movement actors and the media decreased because interdependency between them declined as a wider r, II range of voices joined the debate about climate change, and as the Internet offered environmental groups alternative means to communicate. These findings support Habermas' notion of communicative action as a valuable avenue by which to pursue the study of influence.
224

The sources, fate and dynamics of abandoned metal mine water pollutants : a catchment scale investigation of the River West Allen, Northumberland, UK

Gozzard, Emma January 2008 (has links)
The implementation in 2003 of the EU Water Framework Directive (2000/60IEC) in England and Wales necessitates addressing water quality issues at the river catchment scale, In the first instance, the overall aim of the Directive is to achieve 'good ecological and chemical status' in all surface and ground water bodies by 2015. Principally due to the presence of elevated metals concentrations, abandoned mine water pollution has been identified by the Environment Agency (England & Wales) as a potentially major impediment to meeting this aim. Particular uncertainty surrounds the importance of diffuse sources of pollution from abandoned mines, the sources and quantification of which have been poorly studied to date. The overall aim of this study was therefore to investigate the importance of diffuse sources of ,,- metals pollution associated with a former-mining district. Within this overall aim, primary objectives included an assessment of the role of diffuse sources under varying hydrological conditions, and an investigation of the potential significance of riverbed sediment as a source and sink o~ metal pollutants. The study site, the River West Allen catchment, Northumberland, forms part of the Alston Block in the north Pennine orefield, the mineral veins of which are largely hosted in Carboniferous Limestone strata. The area was principally worked for zinc (and lead) for over 300 years. As a result, the river is now impacted by three distinct point discharges from these now long abandoned lead-zinc mines. Preliminary reconnaissance surveys illustrated that the pollution arising frpm these drainage adits primarily influences the river's total zinc concentrations, which heavily exceed European statutory environmental quality standards (EQS) throughout much of the catchment. Thus, the sources, fate and dynamics of zinc was the principal focus ofthe work. In this study, synchronous monitoring of aqueous hydrochemistry, flow measurements, and river bed sediment geochemistry, has been -routinely carried out under varying flow conditions for over a year. This has enabled the calculation of the contaminant metal loads at point mine water discharges and selected river locations, under differing hydrological conditions, thus establishing the overall impact of point mine waters within the catchment, and allowing the derivation of contributions from diffuse mine water pollution to the instream totals. In addition, sampling and analysis of river bed sediments (including sequential extraction procedures) has allowed an assessment of the potential importance of such materials as a contributor to diffuse metals pollution. The results of the investigation show that during low flow conditions point source mine water pollution contributes significantly to zinc loadings in the river. In fac~ the total zinc loading . - - ~ - of pojnt sources far exceeds that of the zinc loading in the river downstream of these discharges in low flow conditions (by up to 440%), suggesting considerable attenuation of zinc within the river channel. At all sample sites in the river EQS values are exceeded by up to a factor of 37. Under higher flows instream zinc concentrations exceed EQS values by up to a factor of 57. Point source contributions to total instream zinc loading become far less significant, falling to as little as just 10%. Thus diffuse sources of zinc pollution (i.e. those unaccounted for in the zinc mass balance calculated from point source and instream loadings) account for up to 90% of the instream zinc load, highlighting the dynamic importance of diffuse inputs. Possible diffuse sources include 1) sediment resuspension, due to scouring of metal contaminated river-bed sediments, .q.fld possible subsequent metal remobilisation, 2) direct groundwater input via the hyporheic zone and 3) surface run-off from mine spoil. Of these diffuse inputs the resuspension and possible remobilisation of heavily contaminated sediment has been .investigated in detail here, and appears to be an important potential source of increases in the instream zinc loading during high flow events. The instream concentration and loading of total suspended sediment increases approximately 30-fold and 2,200-fold, respectively, from low to high flow, suggesting sediment resuspension is a key process in releasing zinc into the water column. Zinc concentrations within river-bed sediments typically ~ange from 6,000 - 75,000 mg/kg. These values far exceed interim threshold concentration limits (currently adopted by the Environment Agency) by up to a factor of 600. The majority of this zinc is deemed 'potentially available', as approximately 50% of the total zinc concentration IS associated with carbonates and hydrous ferric oxides. Therefore, changes within pH or redox conditions within the water column may have the potential to remobilise particulate zinc. This work emphasises the potential importance of diffuse sources of mine water pollution in river catchments in former mining districts. In the River West Allen the proportional significance of such point and diffuse sources to total instream zinc loading differs under varying hydrological conditions, and the findings have implications for the management of such pollution issues more widely. For example, it raises questions as to whether treatment of point mine water sources alone will result in measurable environmental benefits in terms of meeting the objectives of the Water Framework Directive. In the River West Allen catchment, while remediation of the point sources of mining pollution would lead to improvements in low flow water quality, the legacy of mining pollution in sedimentassociated metals, and possibly other sources of diffuse metals contamination, may continue to provide an ongoing source of diffuse metal pollution at higher flows.
225

Microbial ecology of a derelict manufacturing gas plant soil and its intrinsic bioremediation potential

Arce, Hilda Monica Romero January 2009 (has links)
No description available.
226

Reducing the Availability of Sediment Pollutants through Activated Carbon Amendments

Hale, Sarah Elizabeth January 2009 (has links)
No description available.
227

Effects of cement dust and its constituents on fungal growth

Mlitan, Abdulmajeed Bashir January 2009 (has links)
Environmental pollution by cement is a serious problem and its effects on humans and plants have warranted careful attention in Libya in recent years as well as in the rest of the world, whereas the effects on fungi have not been investigated enough. This research aimed to investigate effects of cement dust pollution on fungal populations and how cement dust influences fungal growth. Soils and leaves from a cement-dust-polluted area near the Alkomos cement factory in Libya were studied. The physiochemical characteristics of soils in the study area indicate a strong influence by cement dusts that have settled 011 the soil from the cement factory. Calcium content and pH were higher than in similar unpolluted soils in this region. The dominance of fungi of soil and leaves was lowest at 100 m from the factory and the evenness and diversity increased at this site compared to the control area and 250 m from the factory . Variability and diversity of fungi were greater in the Summer (dry season) than the winter (rainy season). Aspergillus, Penicillium, and Fusarium were the most prevalent fungi isolated from contaminated samples.
228

Towards Rational Risk Assessment : Improving biodegradation tests through an understanding of microbial diversity

Goodhead, Andrew Kenneth January 2009 (has links)
No description available.
229

An empirical analysis of water pollution in India

Barua, Anamika January 2009 (has links)
No description available.
230

Assessing management effectiveness : indicators for marine protected areas in British Columbia, Canada

Heck, Nadine January 2010 (has links)
No description available.

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