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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.
11

National strategy, local practice and the solid waste management gap? : a local authority management perspective on sustainable solid waste management in the UK

Read, Adam David January 2001 (has links)
Solid waste management is a field of great diversity and dynamism throughout Europe. Over the last 30 years waste and its management has become a significant environmental risk and an area of growing political importance in the UK. This has been paralleled by developments in European policy and standards linking the environment with the economy and society as the three pillars of sustainability. This thesis examines some of the developments in solid waste management and practice in the UK, using a range of techniques (surveys, case studies, interviews etc.) to analyse changing policy strands and their implications at the local scale where waste management is so evident and important as a municipal service or utility. The development of sustainable waste management (that which does not impinge upon future generations) is now a primary policy field of the current Labour Government, and the amount of consultation, policy and guidance documents published over the last 4 years pays credence to this. This thesis will utilise this political and strategic backdrop to describe and evaluate changes in local service provision (waste bins, recycling collections, frequency and coverage etc.) and local strategies. It is suggested by this research that for all the developments in waste management policy and guidance at the national scale, little has filtered through to new activities at the local scale (through district, borough, unitary or county councils). This is attributed to lack of financial and staff resources to implement the necessary changes, lack of flexibility in terms of existing contractual arrangements and the inability of the authority to engage the public in the new services on offer. This thesis deals with the reasons for this general lack of action, and uses case studies to illuminate where positive contributions to local policy and practice have occurred. Through the series of related papers presented in this thesis, drawn together from the research programme over the last 5 years, an assessment of what has worked and why is provided in terms of sustainable solid waste management policy and subsequent practice. By learning from these examples more local development, in terms of public acceptability, economic affordability and environmental sustainability, is expected in the coming decade. Through an examination of the landfill tax credit scheme, waste minimisation project clubs and the Recycling Roadshow public education campaign a flavour of what can be achieved in terms of solid waste management is provided. These examples highlight how the most common barriers to successful policy implementation (the public, the finances, and the political will) can be overcome at the local scale. This research has made a significant contribution to the current debate in the UK on the path towards improved sustainability in waste management services (as noted by the number of articles that have been published and the author's input to international conferences) and has provided evidence for local councils in justifying decisions relating to their service provision and policy development (through the author's continuing consultancy record).
12

The business case for sustainability : a small firm perspective

Revell, Andrea January 2008 (has links)
The empirical research outlined in this submission explores the environmental attitudes and practices of owners of small and medium-sized enterprises (SMEs) in the UK and Japan. The submission spans three studies conducted over a period of seven years from 2000-2007, involving interviews with a total of 70 owner-managers and 22 government and industry 'key informants', as well as survey responses from 220 SMEs. The research provides a dynamic picture of the barriers and drivers of environmental reform within small businesses during this time, embedding the findings within broader debates on sustain ability and 'ecological modernisation' (EM) theory. A key conclusion of the research is that an SME policy strategy which relies too heavily on voluntarism and self-regulation is unlikely to be effective due to the many internal and external barriers to environmental management experienced by owner-managers. A more participatory and interventionist approach, which combines education initiatives with stricter regulatory controls, market-based instruments and negotiated decision-making is highlighted as a potentially more successful way to encourage SMEs to reduce their environmental impacts. The responses of business owners also highlight that to achieve environmental goals, it is just as important to encourage a change in culture amongst customers as it is amongst companies. The research thus recommends that EM scholars broaden their focus to include the ecological modernisation of consumption, and to engage with contested concepts such as 'sufficiency' and equity in order to ensure that theory can still have currency and gravitas in debates on sustainable development.
13

Lithostratigraphy, foraminiferal biostratigraphy and geological history of the Upper Cretaceous in West Jordan

Shahrour, Yousef Taher Yousef January 1996 (has links)
The stratigraphy of the Upper Cretaceous (Cenomanian - Lower Maastrichtian) rocks in West Jordan is described based on four measured sections: Ajlun/Jerash (north); Wadi Mujib (central); Wadi Mussa and Ras en-Naqb (south). Over 285 samples collected from these sections were processed for microfossils; 214 samples were thin sectioned for microfacies analysis. Despite significant lithofacies changes southward, eight formations and six members have been recognised and correlated across the region. The thickest marine strata are located in the northern and central areas; thicknesses decrease and the sand content gradually increases towards the south. Microfossil, principally foraminiferal, biostratigraphy has been used for detailed stratigraphic correlation. Over 420 species constituting 170 genera are documented, many for the first time from the area. Microfossil species identified include 80 planktonic and 331 benthic foraminifera (104 calcareous and 227 agglutinated), and 10 radiolaria. Taxonomic analyses of all foraminiferal and radiolarian species are presented, including remarks on each species and its geographic and stratigraphic distribution. Most species are illustrated by Scanning Electron Microscope (SEM) photographs. Microfossil range charts are presented for each measured section, based on detailed analysis of each microfossil sample, and local assemblage zones are described. Six regional foraminiferal assemblage zones are proposed: Conorboides umiatensis / Haplophragmoides spp. Zone (lower to mid-Cenomanian); Heterohelix calabarflanki / Whiteinella inornata Zone (upper Cenomanian); Gavelinella stephensoni / Whiteinella archaeocretacea Zone (Turonian); Archaeoglobigerina blowi / Concavatotruncana concavata Zone (upper Coniacian - Santonian); Rugotruncana subcircumnodifer Zone (upper Campanian); Globotruncanella havanensis Zone (lower Maastrichtian), based largely on evidence from Wadi Mujib, which is proposed as a reference section for the area. Palaeoenvironmental studies, including microfacies analyses and the quantitative evaluation of foraminiferal assemblages (planktonic and benthic), provide evidence of four major marine sedimentary sequences: (1) early - mid Cenomanian; (2) late Cenomanian - middle Turonian; (3) late Coniacian - late Santonian; (4) early Campanian to early Maastrichtian, each separated by hiatuses caused either by global falls in sea level and/or local tectonic activity.
14

Landslides in the Lower Greensand Escarpment of South Kent

Hopper, Anna January 2000 (has links)
In 1988, an area of landslides, known as The Roughs, situated on the Lower Greensand Escarpment, in the Wealden district of South Kent, started moving, after an extended period of stability. The Roughs had degraded to a low angled slope since being abandoned by the sea. This thesis undertakes to discover what triggered this reactivation, to clarify the mechanisms, magnitude and rate of the landslides and deduce the significance of the reactivation on other dormant landslides in the UK. The investigation was approached by the undertaking of a detailed desk study, a comprehensive series of fieldwork campaigns, and a statistical analysis of rainfall and a stability analysis of the slope. Although many investigations have been carried out in and around the research site, this thesis further contributes to the knowledge of the subject in the following ways. i Confirmation of detail in the geotechnics of land movement and how they relate to geological structure in the Lower Greensand Escarpment, Bilsington to Folkestone. ii. New geological sections through The Roughs. iii. Indications of the topographic; hydrological and other reasons for the exact location and extent of landslide activity in 1988 and later. iv. Qualitative discussion on the concept of cyclic variations in the factor of safety. v. Quantitative analysis of the effect of wet weather periods on The Roughs. vi. The use of both the infinite and the "finite" slope methods to analyse the stability of the degradation zone. vii. Examination of the effect of raised ground water levels on the stability of the site using other stability analysis methods. viii. An explanation of the sequence of events during the land movements. ix. New insights into the events at Stutfall Castle.
15

The characterisation and origin of hydrocarbons in alkaline rocks of the Kola Alkaline Province

Potter, Joanna January 2000 (has links)
The origin of hydrocarbon-bearing fluid inclusions in igneous rocks remains controversial. The hydrocarbons may be of biogenic or thermogenic origin but most occurrences indicate an abiogenic origin. A variety of mechanisms have been proposed for the generation of abiogenic hydrocarbons which include a direct mantle origin, the respeciation of a magmatic fluid at low pressures and temperatures or the generation of hydrocarbons by a post-magmatic, low P-T process. The large Devonian alkaline intrusions, Khibina and Lovozero, in the Kola Alkaline Province, northwest Russia contain abundant CH[sub]4-dominant inclusions, which consist predominantly of a low-density methane vapour. These inclusions also contain significant concentrations of higher hydrocarbons up to C[sub]6 and hydrogen. They are secondary in nature, occurring as large regular inclusions or small trails of inclusions, which follow the cleavage planes of the host minerals. They are closely associated with the late minerals magnetite, biotite, aegirine and hydrated Na/K-silicates along with occasional H[sub]2 O-dominant fluid inclusions. A comparative study of the fluid inclusions in the nearby Devonian carbonatite intrusions, Kovdor and Sokli, shows that these intrusions are dominated by complex primary aqueous fluid inclusions. The main gas phase present is carbon dioxide. Hydrocarbons are not found at Kovdor but may be present in Sokli as small, secondary, monophase gas inclusions associated with phlogopitization and serpentinization of the mineral assemblage. The CH[sub]4-dominant fluid inclusions in Khibina and Lovozero were trapped as secondary inclusions at low pressures and temperatures at or near the CH[sub]4-H[sub]2 O solvus around 350 °C and 0.5 to 2 kbar. Isotopic results indicate the methane is abiogenic in origin ([delta][sup]13 C [sub]CH4 < -30 %). Therefore, a post-magmatic, abiogenic process generated the CH[sub]4-dominant fluid. The methane and higher hydrocarbons were generated via the Fischer-Tropsch reaction; nCO[sub]2 + (3n+1)H[sub]2 -> C[sub]n H[sub]2n+2 + 2nH[sub]2 O. A magmatic CO[sub]2 -rich fluid, that may be represented by the CO[sub]2 dominant fluid inclusions found in the Khibina carbonatite, reacted with hydrogen produced from hydrothermal reactions that replaced arfvedsonite, nepheline, augite and titanomagnetite with aegirine, biotite, magnetite and hydrous Na/K-silicates. The water produced by the Fischer-Tropsch reaction was recycled initiating further hydrothermal reactions setting up a cycle of alteration and hydrocarbon generation. Fischer-Tropsch synthesis of hydrocarbons in igneous rocks linked to post-magmatic hydrothermal alteration may be a lot more widespread than previously thought. This may have implications in the future for finding, or producing further natural gas resources.
16

Late Quaternary vegetation history of the acidic lithologies of South East England

Groves, Jonathon Alexander January 2008 (has links)
There have been few Late Quaternary vegetation records from the acidic lithologies of south east England. This study reports on investigations from three new valley mire sites (Bagshot, Conford and Hurston Warren), using pollen and charcoal analyses with chronologies provided by radiocarbon dating. The Bagshot sequence begins at c. 12750 cal. BP with high Betula and Pinus sylvestris pollen values recorded during the late-glacial and early Holocene respectively. After a hiatus from c. 9800 to c. 7550 cal. BP, the dominant taxa are Quercus, Tilia and Corylus avel/ana-type. Tree pollen values decline from c. 3750 cal. BP, with Calluna vulgaris recorded from c. 3450 cal. BP. At Conford, high Pinus sylvestris values persist for c. 4700 cal. years from c. 10750 cal. BP. Increases in Quercus, Tilia and Alnus glutinosa occur at c. 6050 cal. BP. Here, tree pollen values decline from c. 2900 cal. BP with Calluna vulgaris then consistently recorded, along with other indicators of anthropogenic activity. The Hurston Warren sequence begins at c. 4400 cal. BP with high Quercus, Tilia and Corylus avellana-type pollen values. A fall in Tilia percentages from c. 3050 cal. BP is again followed by higher Cal/una vulgaris values and the appearance of anthropogenic indicators. Discussion focuses on the vegetation history of Pinus sylvestris in lowland England, anthropogenic activity associated with declines in Tilia pollen values and the development and persistence of heathland. In the early Holocene, while Pinus sylvestris was rapidly excluded from the more fertile soils of lowland England, in areas of poor sandy soils Pinus sylvestris often achieved dominance, which locally persisted into the mid-Holocene. Examination of palaeoecological trends associated with declines in Tilia abundance across lowland England has led to the identification of a number of processes that are responsible, though the majority of the declines are associated with clearance activity. The latter primarily occur during the Late Neolithic to Mid-Bronze Age. Their number is substantially reduced from the Late Bronze Age; however, this may in part reflect the scarcity of remaining Tilia woodland. The earliest of these declines appear to have occurred in areas of fertile soil; though by the Mid-Bronze Age they are focussed on the acidic geologies of south east of England. Extensive heathland development did not occur in these areas until the Bronze Age when expansion is associated with either an increase in pastoral activity or the frequency of burning. Once established, heathland areas appear to have been maintained into the historic period by these traditional management practices. At Hurston Warren and Conford, heathland areas appear to have expanded during the Anglo-Saxon and early Medieval period respectively.
17

A GIS-based approach to reconstructing mid-20th century agricultural land use around Lewes, East Sussex

Taylor, Katherine Jane January 2009 (has links)
The main objective of this project has been to reconstruct agricultural land use around Lewes, East Sussex between 1931 and 1959. The key aims were to contribute to the debate around theories of productivism and to demonstrate the power of GIS as a tool for historical reconstruction. The data for 1931 included the field sheets and one inch maps from the First Land Utilisation Survey, and significant differences were identified between these two sources. The data for the early 1940s included the maps and forms from the National Farm Survey along with a Luftwaffe aerial photograph. Using these, some farms were reconstructed successfully, although there were issues with the consistency of the data. The remaining datasets were aerial photographs from 1945/7 and 1959 along with the parish summaries of the 4th June agricultural census data. In terms of the productivism debate, a fuller definition of pre-productivism was proposed as a result of examining the 1931 data. The shift towards productivism in this part of East Sussex was considered by looking at the snapshots of land use provided by the different datasets. A clear growth in arable land, an increase in farm size and intensification in terms of livestock farming was identified. Finally the use of GIS allowed the integration of disparate datasets and the mapping of different types of land use in a way that has not previously been attempted for this area.
18

Tectonic setting, age and emplacement mechanisms of the end-Cretaceous to Palaeocene magmatic arc system, Precordillera of Vallenar, Northern Chile

Truelove, Leigh January 2007 (has links)
The emplacement of the end-Cretaceous to Palaeocene magmatic arc in the Precordilleria of Vallenar occurred during a fundamental switch in deformation style of the upper plate of the Andean margin from extension/transtension to contractional deformation. This switch in regional tectonics is shown by combining precise [sup]40 Ar/[sup]39 Ar geochronology with microstructural and structural field observations that demonstrate a direct link between the ages for emplacement, cooling and subsequent deformation of end-Cretaceous to Palaeocene magmatic arc. The emplacement of the Las Campanas pluton during upper plate extension, 70.6 ± 1.3 Ma, was accommodated by a floor-subsidence mechanism that normally reactivated the east-dipping Agua de los Burros extensional growth fault. This generated a steep upper amphibolites-facies, syn-plutonic, brittle-ductile, dip-slip shear zone that is located on the pluton's western side and exhibits a consistent east-down sense of shear. [sup]40 Ar/[sup]39 Ar hornblende and biotite ages from the pluton interior and shear zone are the same, within error, which demonstrates rapid cooling of the pluton. The emplacement of the Chehueque pluton, 69.1 ± 0.62 Ma to 66.75 ± 0.62 Ma was also accommodated by floor-subsidence mechanisms during upper plate extension, but a switch from regional extension/transtension to contraction can be occurred prior to cooling. The Chehueque pluton has an upper-amphibolite facies brittle-ductile shear zone along its western margin, similar to that of Las Campanas. However, this shear-zone is much wider and shows both east-down and east-up sense of shear indicators. This duality in shear sense is attributed to two phases of deformation during the emplacement and subsequent cooling in this part of the Palaeocene magmatic arc. The initial extensional phase is directly linked to floor-subsidence emplacement mechanisms that generated passive down-bending in the host rocks, towards the pluton. This was closely followed by deformation linked to the initial stages of regional contraction that superimposed an east-up sense of shear; these kinematic indicators can be matched between the host rocks and pluton. This difference in syn-plutonic deformation style and the ages of the Las Campanas and Chehueque plutons therefore constrains the time of the switch from regional extension/transtensional deformation to contractional deformation to a period of c. 4 Myr in latest Cretaceous to early Palaeocene time in the Precordillera of Vallenar.
19

Fate of contaminants at an abandoned mining site in an arid environment

Sims, Douglas B. January 2011 (has links)
Mining exploitation of mineral resources in the American West has been an important factor in westward expansion. However, this legacy might pose a significant risk to the wider environment. Previous assumptions were that abandoned mining sites in hyperarid regions posed no significant threat. Three washes in Nelson, Nevada (USA) were evaluated to determine if trace elements and Cyanide from abandoned mining sites have migrated downwash in a hyperarid climate. Data show that this assumption is true with respect to current environmental conditions, however, future climate changes have not been considered. Data show that the Carnation, Eagle, and Techatticup wash sediments contained low concentrations of CN[sup]-, Hg, Ag, As, Pb, and Se, but above background levels. It was found that contaminated sediments containing CN[sup]-, Ag, As, Ba, Cd, Cr, Hg, Pb, and Se have migrated at least 6000 m. Furthermore, research has shown that creosote bush in the affected parts of the washes has accumulated small amounts of trace elements As, Cr, and Se in its leaves, but other trace elements present in wash sediments (Ag, Cd, and Pb) have not been taken up. The current environmental conditions provide for a low risk to downwash areas based on low concentration of CN[sup]- and trace elements when compared to the United States Environmental Protection Agency's screening levels. However, if environmental climate changes were to occur, the risk to downwash environments may increase. There are more than 1000 abandoned mining sites in Nevada and countless more across the globe that are located in similar environments. It has been shown that it is possible for mine tailings in Nelson, Nevada to migrate in a hyperarid climate indicating a site may pose a greater risk as a result of climate change. Sites with significantly more contaminated sediments could be at a greater risk for waste to be mobilized into the wider environment due to climate change. If the local environment is effected by an increase in precipitation or intensification of storm events, pathways for contaminants to enter the wider environment could ultimately impact or pose a more significant risk to the wider environment.
20

Spatial and temporal scales of the morphodynamic evolution within the Studland complex

Cook, Rebecca Louise January 2007 (has links)
This research has analysed the large sandy beach at Studland Peninsula over a range of spatial and temporal scales, recording a range of geomorphic features and the processes by which they evolve. The aim was to understand better the morphodynamic evolution of the coastal system over different temporal and spatial scales and identify the extent of changes operating along the beach system. The research has sought to quantify shoreline change from the historical archive by providing an interpretation of the evolutionary sequence of the Studland system over the last 500 years. The linkage between the ebb tidal delta and shoreline progradation has been reviewed. In addition,the temporal variability of the beach system between 2001 and 2004 has been examined. These objectives have been combined to produce a nested hierarchy of spatial and temporal change in the Studland system in order to re-evaluate already existing conceptual models of sediment transportand process. Historic change within the system has been undertaken by a review of historic maps, charts and aerial photographs. Ground Penetration Radar was used to determine the subsurface stratigraphy, providing an indicator of the extent of onlapping and offlapping sand sheets and an interpretation of the morphostratigraphy. Swath bathymetry was used to examine contemporary seabed change within Studland Bay. Regular beach profiles provided datafora time series analysis to be applied to determine temporaland spatial beach behaviour. This study has contributed to furthering the understanding of beach systems by providing a comprehensive overview of beach behaviour on a variety of levels, from the littoral cell to a morphological feature. The study has progressed the understanding of beach sensitivity, and the interplay between ebb tidal deltas and beaches.The results reveal that the Studland Beach system operates as a nested hierarchy of scales, responding to a range of timescales from the historical to the annual. Morphological changes operate at high and low frequencies. The historical trend is for foreshore progradationin the north and erosion in the south. The pattern of variability revealed the importance of sediment feed from the ebb tidal delta to the beach,confirmingthe Poole Harbour entrance is a major contributor to foreshore change. The decadal trends illustrate an accumulation of short-term trends with on and off shore sediment feed via the ebbtidal delta; beach change is muted or hidden by more dynamic frequency variations. Conceptual models were developed to understand geographical relationships between form, process and scale, thus illustrating the relationships between controlling variables, temporal and spatial beach form variability and the system's hierarchy. Profile variability revealed several distinct patterns of spatial and temporal change, enabling discrete sets of profiles to be grouped together to illustrate the complicated relationship caused by geographical and spatial profile variation. Wider beaches with greater profile variability signified stability and accumulation. Scarcity of morphologicalfeatures reflected greater susceptibility to erosion. Furthermore,the study allowed morphological variability to be mapped out, thus providing a complete understanding of the relationships between form and process, at a level of scales never undertaken before.The models have revealed a compartmentalised hierarchical sediment system related to the survivability of beach features; morphological variability and beach stability,linking the components of the system with the whole of the Bournemouth Bay littoral cell.

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