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2004

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Articles 71791 - 71801 of 71801

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New Strategies To Determine The Distribution Of Trace Elements In Soils And Sediments, Rebeca Santamaria-Fernandez Jan 2004

New Strategies To Determine The Distribution Of Trace Elements In Soils And Sediments, Rebeca Santamaria-Fernandez

School of Geography, Earth and Environmental Sciences Theses

Sequential chemical extraction to fractionate metals in soils and sediments into different groups reflecting their "leachability" has been widely employed to determine distribution of metals in different physico-chemical phases. A large number of sequential extraction schemes have been reported, most of them modifications of Tessier's extraction protocol. Although this method has been widely accepted, it is important to highlight that sequential extraction procedures are often tedious and time consuming and that they also suffer from a number of limitations, such as the problem of achieving selective dissolution and the re-adsorption of trace metals during extraction. The objective of this study …

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Foraminiferal Distribution And Sequence Stratigraphy Of Oxfordian Successions In The Wessex/Anglo-Paris Basin, Melissa Jane Oxford Jan 2004

Foraminiferal Distribution And Sequence Stratigraphy Of Oxfordian Successions In The Wessex/Anglo-Paris Basin, Melissa Jane Oxford

School of Geography, Earth and Environmental Sciences Theses

The use of micropalaeontology within a sequence stratigraphic context is rapidly emerging as a valuable tool for the recognition of ancient cycles and sequences. This study shows how micropalaeontology can be used to develop insights into sequence stratigraphic interpretations. A micropalaeontology study of two Upper Jurassic, Oxfordian successions from the South . Dorset Coast, U.K. and the Normandy Coast, France provide the basis for this study. A near continuous succession of the Oxfordian from South Dorset and Normandy were obtained, and foraminifera extracted. Examination of the fauna revealed representatives from 23 families, comprising 36 genera and 126 species. All species …

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Landslide Investigation In The Río Aguas Catchment, Southeast Spain, Andrew Barrie Hart Jan 2004

Landslide Investigation In The Río Aguas Catchment, Southeast Spain, Andrew Barrie Hart

School of Geography, Earth and Environmental Sciences Theses

Many remote and/or rural communities Uve under the threat of major landslide activity. These remote areas are also increasingly the focus of development programmes which, without careful consideration of the ground conditions, will be at risk. The cost of mitigating against landslide activity can also be extremely high, possibly making prevention or avoidance the better long-term option. It is, therefore, of prime importance to assess the type and magnitude of the landslide activity affecting an area, particularly during the feasibility and planning stages of any project. The most straightforward approach to any landslide investigation is the compilation of a landslide …

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High-Resolution Records Of Climate Change From Lacustrine Stable Isotopes Through The Last Two Millennia In Western Turkey, Matt Jones Jan 2004

High-Resolution Records Of Climate Change From Lacustrine Stable Isotopes Through The Last Two Millennia In Western Turkey, Matt Jones

School of Geography, Earth and Environmental Sciences Theses

Knowledge of past chmate variability is vital if the causes of observed chmate changes since instrumental records began are to be fully understood, particularly those, post-1850 AD, possibly due to anthropogenic activity. The past two millennia provide a long enough background with which to compare post-r850 AD change, whilst errors on proxy records remain relatively small. In the Eastem Mediterranean changes in water balance are of particular interest as water is an important resource. Oxygen isotope records from lakes in the region record changes in water balance and are therefore an important archive for observing natural, and anthropogenicaly forced, variabiUty …

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Performance Characterisation Of Ip Networks, Bogdan Ghita Jan 2004

Performance Characterisation Of Ip Networks, Bogdan Ghita

School of Engineering, Computing and Mathematics Theses

The initial rapid expansion of the Internet, in terms of complexity and number of hosts, was followed by an increased interest in its overall parameters and the quality the network offers. This growth has led, in the first instance, to extensive research in the area of network monitoring, in order to better understand the characteristics of the current Internet. In parallel, studies were made in the area of protocol performance modelling, aiming to estimate the performance of various Internet applications. A key goal of this research project was the analysis of current Internet traffic performance from a dual perspective: monitoring …

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Recovery Of The Mersey Estuary From Metal Contamination, Sarah Jane Watts Jan 2004

Recovery Of The Mersey Estuary From Metal Contamination, Sarah Jane Watts

School of Geography, Earth and Environmental Sciences Theses

The Mersey Estuary has received significant quantities of industrial wastes and sewage over several decades. Although contaminant loads are reducing and the estuary is showing signs of recovery, the sediment reservoir remains a repository of historical contamination and still contains high concentrations of trace metals and organic compounds. A combination of hydrodynamic, sedimentary and geochemical processes are responsible for maintaining trace metal concentrations at present-day levels. The distributions of trace metals in bed sediments reflect changes in granulometry, differences in POC content and the magnitude of past inputs rather than the locations of point sources in the estuary. The association …

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Specification Development For The Use Of Devon Cob In Earthen Construction, Kathryn Anne Coventry Jan 2004

Specification Development For The Use Of Devon Cob In Earthen Construction, Kathryn Anne Coventry

School of Geography, Earth and Environmental Sciences Theses

The traditional earthen building practice of cob construction has been historically linked to Devon for many centuries. However no standards or specifications exist to facilitate a technical appraisal of the material. This thesis sets out to develop an appropriate test methodology for the classification and compressive strength determination of Devon cob. The absence of appropriate standards for cob construction is shown as a function of neglect for Devon cob as a potential construction material. National and international events that have re-kindled interest in earth as a building material are discussed, with particular reference to cob construction. A rationale is presented …

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The Interference Free Determination Of Selenium In Environmental And Clinical Samples By Icp-Ms, Justine Clare Turner Jan 2004

The Interference Free Determination Of Selenium In Environmental And Clinical Samples By Icp-Ms, Justine Clare Turner

School of Geography, Earth and Environmental Sciences Theses

The determination of selenium in environmental and clinical samples by ICP-MS is complicated by both poor sensitivity and severe interferences resulting from both the sample matrix and the argon plasma. The purpose of this study was to investigate ways of overcoming these problems thus enabling Se to be determined both accurately and precisely. A novel procedure for the accurate determination of selenium in serum using electrothermal vaporisation inductively coupled plasma mass spectrometry (ETV-ICP-MS) has been developed. A simple 1:20 dilution of the serum with 1% nitric acid negates the need for a lengthy sample digestion procedure. Several of the interferences …

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Conflict And Coastal Aquatic Sports: A Management Perspective, Karen Sumser-Lupson Jan 2004

Conflict And Coastal Aquatic Sports: A Management Perspective, Karen Sumser-Lupson

School of Geography, Earth and Environmental Sciences Theses

This comprehensive study of Coastal Aquatic Sports (CAS) has been undertaken because recorded evidence suggests that the growth of CAS is beginning to hinder the interconnectivity of dynamic coastal and estuarine systems. Integrated Coastal Zone Management (ICZM) and Sustainable Development were selected as the framework for the development of this research. One of the main CAS related areas of concern was first exposed from a pilot study which indicated site saturation is occurring, causing conflict and confliction. Furthermore, evidence suggested that CAS is evolving in isolation from terrestrial sport and social recreational management procedures. Social change and government initiatives have …

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Holocene Sea-Level Changes Along The Channel Coast Of South-West England, Anthony Carl Massey Jan 2004

Holocene Sea-Level Changes Along The Channel Coast Of South-West England, Anthony Carl Massey

School of Geography, Earth and Environmental Sciences Theses

A Holocene relative sea-level (RSL) history for the south Devon coast is reconstructed through an analysis of twelve cores extracted from the coastal back-barrier environments of Bantham Sands, North Sands, Slapton Sands and Blackpool Sands. Foraminifera preserved in the sediments are assigned an indicative meaning based on the vertical distribution of their modem counterparts from contemporary salt marsh and mudflat environments in the Erme and Salcombe-Kingsbridge estuaries. The contemporary data provide the first inter-tidal (-2.6 to +2.6 m MTL) foraminifera-based transfer function for south-west England from which sea-level changes can be predicted with good precision (RMSEP = ±0.29 m). Sea-level …

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Particulate Phytochelatins As An Indication Of Metal Stress In Natural Waters, Silvia Keiko Kawakami Jan 2004

Particulate Phytochelatins As An Indication Of Metal Stress In Natural Waters, Silvia Keiko Kawakami

School of Geography, Earth and Environmental Sciences Theses

The aim of this study was to investigate the metal stress response of phytoplankton in the Fal, Plym and Tamar Estuaries (SW England, UK) by field measurements of particulate phytochelatins (PCs) and glutathione (GSH) and their relationships with Cu speciation. A high performance liquid chromatographic method was optimised for the determination of particulate PCs and GSH from estuarine waters. Dissolved Cu speciation was determined using well established cathodic stripping voltammetric methods. Glutathione was found throughout the estuaries ranging from 0.6 to 274 µmol (g chl α)ˉ¹ , and PCs were detected mostly in the Fal samples at concentrations up to …

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