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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.
581

The development of some aspects of settlement and land use in Sutton Chase

Hodder, Michael Anthony January 1988 (has links)
The development of unenclosed common waste, parks, hamlets, moated sites and isolated individual settlements in Sutton Chase is traced, using archaeological, documentary and environmental evidence. The value of employing a combination of different methods and sources in the study of landscape development is shown, provided their potential and limitations are critically assessed. The largest waste areas were probably heathland by Roman times, and they were conserved through the Middle Ages as part of the hunting reserve of Sutton Chase, but following the demise of Sutton Chase in 1528, settlement and cultivation of waste areas was encouraged. Deer parks were created in parts of the study area between the 12th and 14th centuries. In the later Middle ages some of these were extended and new parks were created. Most of the hamlets and individual settlements were shown to have been in existence by the Middle Ages, but few of them were on the same sites as Roman settlements. The relative influence of the physical environment, population fluctuations and human policy in the development of the landscape is discussed, and possible future work suggested by the results of the study is outlined.
582

Correlations between fluviatile sandstone lithofacies and geochemical properties and their importance for groundwater contaminant transport

Jaweesh, Mahmoud January 2018 (has links)
Reactive groundwater contaminant transport is dependent upon hydraulic and geochemical property distributions. The aim of this research was to determine, for an example fluvial sandstone: (i) the degree of correlation between geochemical property values and lithofacies (LFs); and (ii) the effect of the correlations on reactive solute transport. A 60 m core from the carbonate-cemented, red-bed Triassic Sherwood Sandstone Group was examined. Five fluvial LFs were identified, in fining upwards cycles from a channel lag sandstone (LF5) to a low energy mudstone (LF1). The main geochemical properties investigated were carbonate content, oxide content, sorption capacity, cation exchange capacity (CEC) and selectivity coefficient; Surface area and colour were also studied. There is a clear distinction in carbonate content, CEC, selectivity coefficient and Fe and Mn oxide content between LF1 and LF2, the ‘mud’ LFs, and the matrix of LF3, LF4 and LF5, the ‘sand’ LFs. In addition, the pellets change the bulk geochemical properties of the sand LF units. Modelling indicated that the pellets can affect solute mobility significantly. Selectivity coefficients show a possible depth zoning. Distribution parameter values obtained characterize the sequence for geochemical modelling and uncertainty estimation. Oxide coating thickness was estimated at about 100nm. CEC was found to be well-correlated with surface area. Colour/Fe/Mn content correlations suggest a possibility in future to use colour logging to indicate oxide content and possibly even surface area and CEC. As the sequence examined appears typical of many red-bed fluvial sequences, it is suggested that the findings may also be typical of other similar continental sandstones.
583

A social evolutionary perspective on understanding Chinese climate policy : state elites, ideas and national interests

Du, Sen January 2014 (has links)
China has been the world’s largest emitter of greenhouse gases in the absolute terms since 2008. Yet the pivotal drivers and key factors in its climate policymaking are still much under‐researched. In particular, little attention has been given to developing theoretical models to account for and to explain the evolution of Chinese climate change policy. This study directly addresses this gap in the climate change literature. Firstly, the study identifies the key domestic drivers and factors in Chinese climate policies using social evolution theory, which incorporates facets of institutionalism and elite theory in order to explain the evolution of Chinese climate change policy by direct reference to its highly dynamic socio‐economic circumstances. Secondly, this study uses these social evolutionary insights to inform interviews with 11 key climate policymakers situated at the highest levels within the Chinese Communist Party and the climate policymaking organisations. Respondents’ verbatim comments are analysed using NVivo software to critically assess the validity of social evolutionary analysis conducted in the first part of the thesis. Not only does this provide a vital means of empirical confirmation, it also directly contributes to the very scarce body of academic work on Chinese political elite interviewing. Thirdly, the analysis builds on this domestic level analysis to examine the extent to which social evolutionary theory might be used to understand and explain Chinese climate policies. Implications are discussed to inform future domestic and international climate policymaking and global cooperation on addressing climate change.
584

Transfer of low-carbon technology under the United Nations Framework Convention on Climate Change : the case of the Global Environment Facility and its market transformation approach in India

Haum, Rüdiger H. January 2011 (has links)
The transfer of low-carbon technology to developing countries is one of the key means to reduce greenhouse gas emissions in developing countries and therefore a key aspect of the United Nations Framework Convention on Climate Change (UNFCCC). This thesis aims to contribute to the understanding of international low-carbon technology transfer and how it might do justice to the interest of developed and developing countries. The empirical example is the technology transfer approach and its implementation by the Global Environmental Facility, which acts as the financial mechanism of the UNFCCC. My theoretical framework includes two sets of theories. The first includes theories of international technology transfer. This set explains how international technology transfer may lead to economic benefits on the side of the technology recipient. This theory, however, does not explain how international technology transfer will lead to significant environmental benefits. I therefore included a second set of theories in my theoretical framework. Theories of diffusion of environmental technologies explain how technology might achieve environmental benefits such as the reduction of greenhouse gas emissions in developing countries. A case study was chosen as method. In order to do justice to the research question, the empirical enquiry takes place on three interconnected levels. On the first level, the positions of developed and developing countries on the subject of technology transfer under UNFCCC were established. These serve as additional yardsticks for the discussion of the GEF approach and its outcomes. On the second level, the technology transfer approach of the GEF and the relationship to GEF and UNFCCC on the subject on technology transfer was established. On the third level, the GEF project Photovoltaic Market Transformation Initiative (PVMTI) in India, which follows the GEF approach to technology transfer, was investigated. The thesis concludes, in relation to the research question, that the current GEF approach to technology transfer is unlikely to achieve the goals of both developed and developing countries. It is able to achieve the goals of developed countries as it tends to prioritise the environmental goals through selected demand side measures that are effective in achieving emission reductions. It is less effective in achieving development goals as international technology transfer is left to the private actor.
585

Amazonian dark earths and Caboclo subsistence on the middle Madeira River, Brazil

Fraser, James Angus January 2010 (has links)
This thesis examines the relationship between Amazonian Dark Earths (ADE) and Caboclo subsistence on the Middle Madeira River, Brazil. ADE are fertile anthropogenic (man-made) soils formed through practices of burning and waste disposal by pre-Columbian Amerindian populations. “Caboclo” is a social category that refers to the people of diverse origins that form the majority of the contemporary rural population of Brazilian Amazonia. Bitter manioc fields (roças) and homegardens (sítios) are the principal forms of Caboclo subsistence cultivation on ADE on the Middle Madeira River. Multi-sited ethnography shows that differences in historical ecology at both local and regional scales either enable or constrain Caboclo subsistence cultivation on ADE. At communities located on long-term landholdings with a history of egalitarian land-tenure and multi-generational kinship there is a rich body of local knowledge and practice relating to the cultivation of ADE. Interviews with 249 farmers in six localities demonstrate that bitter manioc cultivation in fertile soils (floodplain and ADE) tends to be characterised by intensive swidden systems with smaller fields, shorter fallows, and a predominance of what locals refer to as “weak” (low starch fast maturing) landraces. Bitter manioc cultivation in infertile soils (Oxisols and Ultisols) is characterised by more extensive shifting cultivation systems with larger fields, longer fallows and a predominance of what locals refer to as “strong” (high starch slow maturing) landraces. Interviews with 63 households at 16 communities show that homegardens on ADE combine the most common species of homegardens on Oxisols and in the Floodplain, with other species that occur most frequently on ADE. Homegardens on ADE exhibit significantly higher culturally salient species diversity when compared to homegardens on the other types of soil. Collectively, bitter manioc fields and homegardens constitute cultivated landscapes that show diverging agrobiodiversity on different soils, the outcome of an interplay between soil affordances, Caboclo agency and plant responses over time. These findings provide a springboard for some conclusions concerning the relationship between ADE and agriculture in the pre-Columbian period, drawing on what is known from the historical and archaeological record.
586

Climate change and glacier retreat in the French Pyrénées : implications for Alpine river ecosystems

Khamis, Kieran January 2014 (has links)
Climate change disproportionately threatens alpine river ecosystems due to the strong connections between cryosphere, hydrology and physicochemical habitat. Our general understanding of how these systems will respond to warming is, however, based on conceptual models derived from studies undertaken at relatively small spatial scales. This research utilizes: (i) field data collected from five glacierized river basins in the French Pyrénées; (ii) field based experimentation; and (iii) climate/hydrological modelling, to improve understanding of alpine river ecosystem change. Despite a linear, harsh-begin, physicochemical habitat gradient running from high to low meltwater (snow and ice) contribution, observed benthic macroinvertebrate community level metrics were unimodal (i.e. mid-meltwater peak). Community assembly processes shifted from niche filtering/stochastic (trait convergence) at high meltwater sites, to limiting similarity/stochastic (trait divergence) at low meltwater sites. Benthic macroinvertebrate community structure, feeding interactions and body size spectra were altered when invertebrate predator range expansion was experimentally simulated. Empirical observation (space for time substitution) and statistical modelling both suggest an increase in reach scale diversity (alpha) is likely as glacier cover is lost. However, a reduction in habitat heterogeneity is likely to lead to biotic homogenization (reduced beta diversity) as a specialist high meltwater community is replaced by a more generalist community. The need to consolidate monitoring strategies is highlighted and functional trait profiles are suggested as useful bio-monitoring tools for detecting future change.
587

Ensemble-based data assimilation for the climate of the past millennium

Matsikaris, Anastasios January 2016 (has links)
Data assimilation (DA) is an emerging research area in palaeoclimatology. Here, ensemble-based DA schemes are implemented and evaluated for the reconstruction of the climate of some of the key periods from the past millennium. The study is among the first to employ a General Circulation Model for palaeoclimate DA. An off-line and an on-line DA method are first compared, assimilating continental proxy-based temperature reconstructions and using the 17th century as testing period. Both schemes provide simulations that follow the assimilated targets on large scales better than without DA. The on-line scheme has the advantage of temporal consistency of the analysis, and is subsequently used to reconstruct the climate for 1750-1850 AD. The assimilation performs well on large-scale temperatures, but there is no agreement between the DA analysis and reconstructions for regional temperature patterns. Evidence is presented to suggest that this lack of information propagation to smaller spatial scales is likely due to the fact that the Northern Hemisphere continental mean temperatures are not the best predictors for large-scale circulation anomalies, or that the assimilated reconstructions include noise. The lack of regional skill is again found when instrumental data for 1850-1949 AD are assimilated. Based on these results, it is argued that a potential way of improving the performance of DA is the assimilation of temperature reconstructions with higher spatial resolution.
588

Groundwater quality : representative and appropriate sampling of long-screen wells

McMillan, Lindsay Antonia January 2016 (has links)
Groundwater quality sampling guidance typically requires representative samples to be obtained. Such guidance is not always clear what this means and which sampling methods are most appropriate. The situation is complicated by increasing well screen/open interval length. Uncertainty, resulting particularly from observations of vertical flow in wells has led to calls for the use of long-screen (> 3 m) wells to be abandoned for groundwater quality monitoring. Here, four complementary field and modelling studies at various scales are used to examine appropriate groundwater quality sampling in such wells. Numerical modelling demonstrates that literature reported vertical flows in wells < 10 m in length are sufficient to bias pumped groundwater quality sampling. Bias starts for vertical well flow rates less than 50 % of the pumping rate. Vertical flow measurements explain differences and similarities in historical passive sampling between four boreholes and allow vertical aquifer concentration distributions to be quantified. However, such quantification requires per-borehole flow measurement. New technology (Active Distributed Temperature Sensing) provides a versatile alternative to existing borehole flow characterisation methods under ambient and pumping conditions. Data from contrasting field environments demonstrate that even without comprehensive flow investigation long-screen wells can still provide useful information about groundwater concentrations and trends.
589

Electrical induced polarisation properties of saturated bunter sandstones

Collar, Frank Anthony January 1979 (has links)
The research described in this thesis primarily investigates the scope of IP (induced polarisation) as a method of determining the permeabilities of Bunter sandstones in situ. Although a limited amount of preliminary fieldwork has been completed, the project has been largely confined to the laboratory, directed toward identification of the petrophysical factors involved, rather than determination of aquifer geometry. In contrast: to all of the previous studies, the conclusions are supported by a large number of measurements. IP has been measured in the time domain exclusively. Compared to the frequency domain method this offers the advantages of a wider scope of information from which a suitable measure of chargeability may be selected, together with the facility to monitor the potential decay for spurious results. The variation of IP with permeability was investigated for a large number of sandstones with suitable pore water control, and because of the diversity of the results a representative selection of the samples was then subjected to further measurements of IP over a range of pore water salinities. All these data have been described by empirical expressions which relate IP, permeability and matrix conductivity, and some geological implications of these results have been considered. Preliminary fieldwork has been done in the Fylde to find out whether an empirical relationship determined in the laboratory can be used to evaluate field permeabilities directly. The problems involved have been considered and further work in this direction is suggested.
590

Modelling ice dynamic sea-level rise from the Antarctic Peninsula Ice Sheet

Schannwell, Clemens January 2017 (has links)
The Antarctic Peninsula (AP) has been one of the most rapidly warming regions on this planet. This warming has been accompanied by major glaciological changes such as tidewater glacier retreat, ice-shelf retreat and collapse alongside acceleration of outlet glaciers in response to ice-shelf removal. As faster owing glaciers deliver more ice from the ice sheet's interior to the margins, the AP has been identified as an important contributor to global sea-level rise (SLR). However, comprehensible SLR projections of the AP induced by ice dynamics over the next three centuries are still lacking. In this thesis, numerical ice-sheet models are utilised to present scenario-based ice dynamic SLR projections for the AP.

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