Daily 24 hour (00:00 - 24:00) co-located PM₁₀, PM_2.5, and Black Smoke samples were collected for a period of 1 year (September 1999 to September 2000) at an urban background site in central Edinburgh, and monthly at a rural site 30 km SSW of Edinburgh. Sample mass concentrations were determined gravimetrically, and the daily water and acid (2.8:1 HCl/HNO₃ v/v) extractable metal concentrations of Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, and Pb, determined by ICP-MS. Median urban background PM_2.5 water soluble metal concentrations ranged from 0.05 ng m^-3 for Ti to 5.06 ng m^-3 for Pb, and in PM₁₀ from 0.18 ng m^-3 for Ti to 11.74 ng m^-3 for Fe. Median PM_2.5 total (water + acid) extractable metal concentrations ranged from 0.30 ng m^-3 for As to 27.60 ng m^-3 for Fe, and in PM₁₀ from 0.37 ng m^-3 for As to 183.44 ng m^-3 for Fe. Fe concentrations represented c. 80% of the total (water + acid) metal exposure from metals analysed in the PM₁₀ fraction, although Pb and Zn constituted over 50% of the water soluble metal exposure in PM_2.5. Significant seasonal differnces (P <0.05) were observed in the metal concentrations, which varied with metal, coupled with an overall shift towards a higher proportion of acid extractable/lower proportion of water soluble metal in the winter months. Seasonal differences were also present in the urban : rural ratio, which ranged from ~3 in the spring to up to ~10 in winter. Urban background metal concentrations were also found in general to correlate more strongly with BS ‘mass concentration equivalent’ than with PM₁₀ or PM_2.5 mass concentrations. Hierarchical clustering of 5 day air mass back trajectories demonstrated that there were significant differences (P <0.05) in metal concentrations (ng m^-3) and metal ‘enrichment factors’ (EFs, ng μg^-1 particulate matter) depending on air mass source/direction.

Although natural( 17β-ocstradiol) and synthetic( 17a-ethinylestradiol)oestrogens in sewage effluent have been shown to disrupt hormonally controlled processes in a number of animal groups, understanding of their effect upon British freshwater molluscs is limited. The effects of exposure to high (0.1 to 10 mg/L EE2) and low (I to 10,000 ng/L EE2) nominal concentrations of 17acthinylestradiol (EE2 on the freshwater pulmonate gastropod Lyninaea stagnalis were assessed using studies designed to interfere with normal control processes in the life cycle of the animal. At 15degC,the snail was found to spend about 2 weeks developing as an embryo, 3 months growing as a juvenile and up to 2 years producing egg masses as an adult (shell height 22 to about 50 mm). The earliest life stages (embryo and neonate) were most sensitive to the toxicant in short-term exposure studies (e. g. neonate 24h LC50 = 9.4 mg/L; adult 24h LC50 = 14.2 mg/Q. Embryonic development was inhibited and a higher frequency of morphological malformations was found in animals exposed to environmentally relevant levels of EE2 compared to control animals. The animals' sensitivity toward the toxicant lessened following gastrulation. Neonate growth was promoted by the presence of the toxicant at 32-100 ng/L EE2 Whereas it was greatly reduced following exposure to the toxicant at the high μg/L concentration range. Reproduction was greatly influenced by the presence of the toxicant. For example, the quality, though not the quantity, of egg capsules produced was reduced. A number of morphological malformations to the egg capsule were observed and the possible sites of EE2 action on the reproductive tract were discussed. Allocation of packaging material to the egg mass occurred in a triphasic manner with the increased packaging observed at environmentally relevant levels of EE2 (10 ng/L EED lessened in samples from the 1000 ng/L exposure group yet significantly elevated at 10,000 ng/L EE2- Significant mortality was observed in groups exposed to treated sewage treatment plant effluent and control groups. However, the reproductive output, measured as the number of egg masses and capsules, was significantly reduced by the presence of effluent. Several previously unseen malformations to the egg capsule and egg mass were observed. Allocation of packaging material to the egg mass was inhibited by the effluent. As a consequence hatchability of the embryos was reduced in 50 and 100% effluent exposure groups. The implementation of novel bioassay endpoints in L. stagnalis toxicity tests has proven useful in identifying the effects of EE2 on freshwater pulmonate molluscs. The potential for further use of this species as a bioindicator in both laboratory and in situ studies is considered promising and is recommended

Many chemicals enter the marine environment as a result of human activities where they are available to exert a range of effects upon biota. Research has previously focused on the effects of chemicals upon various biological functions of biota in situ. However the impact of chemicals with immunotoxic functions has received little attention. The current research focused on the immunotoxicity of environmental pollutants on marine invertebrates, primarily Mytilus edulis. The aim of the research was to determine to what extent immune function altered in M edulis following exposure to environmental contaminants and how these alterations could be measured and incorporated into environmental monitoring programmes. Exposure of M edulis to the immunotoxicants copper and tributyltin in the laboratory indicated that biochemical measures of immune function were too sensitive for experimental manipulations to be used as biomarkers of pollution-induced stress. However, cellular analysis of immune function, as measured by an adapted immunotoxicity assay in combination with a measure of cell viability, was responsive to pollution-induced stress in a concentration-dependant manner. Cellular immune activity appeared to be regulated by the cytokine IL-1 and involved the release of lytic factors from haemocyte populations. Field evaluation of the immunotoxicity assay in New Bedford Harbour, USA, indicated that environmental contaminants within the estuary had an immuntoxic effect upon in situ mussel populations. The measure of immunotoxicity in mussel populations in New Bedford Harbour was a more sensitive measure of environmental impact than routinely used biomarkers such as lysosomal neutral red, cardiac monitoring and condition index. The immunotoxicity assay is therefore proposed as a sensitive, low cost and reliable biomarker of effect in mussel populations both in the laboratory and the field.

Contemporary climate change politics, dominated by neoliberal and ecological modernisation framings, has reached an impasse. This thesis investigates whether a Marxist critique focused on trade unions might offer an alternative approach. It critically analyses the social science literature on climate change and utilises insights from the employment relations literature to interrogate trade union activities. The thesis makes original contributions to both the climate change and employment relations literatures. First, it offers a critique of the dominant climate politics and suggests an alternative framing. Second, it proposes a theorisation of organised workers and trade unions as strategic climate actors, applying Hyman's triangular model of market, society and class to understand union behaviour on climate change. Third, it contains a theoretically informed and empirically grounded investigation of UK trade union policy and practice on climate change at the start of the 21 st century. The main findings are that some socialists, trade unionists and activists in the UK have introduced a working class perspective into climate discourse, including challenges to property relations, climate inequality and through mobilisation. Some trade unionists have foreground the occupational aspects of climate change and climate policy, and made distinctive demands for a radical just transition, climate jobs and socially useful work. Trade union climate representatives ("green reps") in some workplaces have made an independent contribution to climate mitigation and adaptation. The occupation of the Vestas wind turbine manufacturing factory and the resulting climate solidarity illustrate the potential power of workers' climate action. The principal conclusions are that workers have the interest and collective capacity to reduce greenhouse gas emissions, to address the differential impacts of climate and climate policy, and to coalesce other actors to tackle climate change. The recent experience of UK trade unions suggests they have a vital role to play as climate actors and, suitably reconfigured, the capability to lead a renewed climate movement.

The number of privately-owned parks has dramatically risen in recent decades across the world. Increasingly, these areas are attracting the attention of academia, government and non-governmental organisations because of their potential to combine biodiversity conservation with sustainable development, which is of particular relevance in developing countries. Little comprehensive information on private reserves, however, exists. This thesis investigates the role that private conservation areas fulfil in the Little Karoo region of South Africa, exploring the politico-economic and socio-cultural reality of private reserves, as well as their contribution towards protecting key elements of biodiversity. An interdisciplinary, political ecology-based research framework was adopted, combining questionnaire surveys, GIS-analyses and interviews. Key findings revealed that the private protected area sector is substantially contributing to the representation of key elemen'ts of biodiversity patterns and processes in the region. Private reserves show high variability and are closely tied to the changeable circumstances of their owners. However, they are principally used for personal leisure, / and further, profit does not constitute a primary driver to their establishment. Rather, complex· networks of human and environmental processes interact across different levels of analysis to drive the growth in private reserves. Landowners perceive themselves to fill a legitimate role in the conservation landscape and increasingly demand recognition from conservation authorities. Successful strategies and policies for optimising the valuable contribution that private reserves make to conservation need, first, to be sensitive to both the ecological and social dimensions of conservation areas. Second, they should focus on raising social capital between landowners, and providing recognition for the conservation role they fulfil, through the provision of extension services. Private conservation areas worldwide are likely to continue increasing in years to come; their potential to provide positive and long-lasting contributions to biodiversity protection warrants increasing interest and support from the wider conservation community.

carbon dioxide (C02) emission to atmosphere (due to fossil fuel fired energy consumption) is a major contributor to greenhouse effect which is causing climate change. Integrated Gasification Combined Cycle (IGCe) power plants have greater adaptability to C02 capture in comparison to the state of the art technology (for Greenhouse gas mitigation). Economic infeasibility, Techno-Economic uncertainty and lack of operational experience are some of the major hurdle preventing further penetration of this technology. As a result, larger amount of contingency is applied to the project cost (for various equipment and sUb-systems of the plant). The aim of this research is to develop a significantly detailed process model (of Hydrogen sulphide and Carbon Dioxide capture from syngas) and to develop a realistic estimate of the size of the plant (to conduct the economic assessment). Detailed process design is developed for H2S and C02 capture from syngas using physical solvent. The physical solvent chosen for this research is a blend of various di-methyl ether of poly ethylene glycol (DMEPEG). Rate based simulations are conducted (using Pro-Treat software) to determine the equipment size, the operating condition and the process performance parameters. Various unit operations (within the process) have been optimized using sensitivity study of various process parameters. Several energy saving features have been introduced in the process which finally result in Reboiler Duty (for H2S capture) as low as 30.67 GJ/Ton (which is 99.5 % of feed) and Energy consumption (for C02 capture) as low as 52.422 kW-Hr/Ton (which is 88 % of feed). Suppliers have been identified for various process equipment and their suggestions have been incorporated to develop the process model, to evaluate the process performance and to estimate the cost of the plant.

Long term, continuous and high frequency measurements of CHBr3 and CH2Br2 from five different AGAGE stations have been presented and analysed in this thesis. The CHBr3 and CH 2Br2 mixing ratio ranged from 0.93 ppt to 65.26 ppt. Their background concentration is approximately 0.98 and 1.01 ppt for the Northern Hemisphere. CHBr3 and CH 2Br2 data correlated very well with each other across all five stations. At coastal locations, both bromocarbons displayed a seasonal variation induced by local, summer production. The seasonal variation detected at Jungfraujoch station was dictated by the stronger summer loss processes. Higher CHBr3 and CH2Br2 concentrations often come from coastal sectors, suggesting macroalgae sources. Through AGAGE measurements, the global CHBr3 emission is estimated to be between 1 ± 0.04 Tg Br y(l and 4.9 ± 0.2 Tg Br y(l (based on 57 to 280 Gg Br yr-1 emission of CH2Br2) via a calculated 0.085 ([CH2Br21/[CHBr31) source ratio estimate. CHBr3, CH2Br2 and several halocarbons' degradation schemes and their subsequent halogen chemistry scheme has been incorporated into a three-dimensional tropospheric Lagrangian Chemistry Transport model - STOCHEM CRI v2-R5 . STOCHEM-CRI allowed us to validate the high emission estimate derived from AGAGE measurements, predict the distribution of the source and product gases and study the impact of CHBr3/Bromine on tropospheric species such as ozone. CHBr3 and CH2Br2 estimated lifetimes in STOCHEM-CRI are shorter than the literature values. Their organic product gases are all short lived species that rapidly degrade and produce inorganic bromine product gases. CHBr3 and CH2Br2 zonal plots indicate possible source gas injection of Br into the stratosphere. Zonal plots of Brx (mainly as Br, BrO, HOBr and BrN02) suggest the possibility of product gas injection of Br into the stratosphere. CHBr3 and halogen chemistry has reduced the overall oxidation capacity of the lower troposphere. 1.12% of the total 0 3 burden is lost per Tg of Br emitted into the model. Other radical species' burden also decreased, while hydrocarbon burdens increased

The objective of this study was to determine the effects of long-term exposure to elevated CO<SUB>2</SUB> on the growth and morphology of seedlings of Sitka spruce and silver birch, with a focus on the effects of elevated CO<SUB>2</SUB> on the expansion, surface characteristics, specific leaf area, anatomy and chlorophyll content of leaves of silver birch. Seedlings of Sitka spruce and silver birch were placed in pots in open top chambers receiving ambient or elevated CO<SUB>2</SUB>. After one growing season there was a significant increase in biomass production in seedlings of Sitka spruce grown in elevated CO<SUB>2</SUB> compared to those grown in ambient CO<SUB>2</SUB>, but after eighteen months this effect had disappeared. The initial increase in biomass was a result of a significant increase in root mass. At the end of the second growing season there was no effect of elevated CO<SUB>2</SUB> on allocation of dry mass. There was no effect of elevated CO<SUB>2</SUB> on total number of branches produced at the end of the second growing season but there was an increase in the rate of branch production. Nitrogen, phosphorus and potassium concentration of leaves was reduced in plants grown in elevated CO<SUB>2</SUB>. After one growing season biomass was increased in elevated CO<SUB>2</SUB> plants by <I>ca</I> 20%, rates of photosynthesis were also higher in elevated CO<SUB>2</SUB> plants. There was no effect of CO<SUB>2</SUB> treatment on root: shoot ratio. There was a significant increase in branch production in plants grown in elevated CO<SUB>2</SUB>, but despite an increase in leaf area production early on in the growing season, there was no difference in total tree leaf area at the end of the growing season. Nitrogen, phosphorus and potassium concentration of leaves was reduced in plants grown in elevated CO<SUB>2</SUB> and leaves on elevated CO<SUB>2</SUB> plants senesced <I>ca</I> one week earlier than leaves of plants grown in ambient CO<SUB>2</SUB>.

The validity of the use of sycamore tree rings for the reconstruction of atmospheric lead pollution histories was investigated. The lead concentration and ²⁰⁶Pb/²⁰⁷Pb profiles of several tree cores collected from the Loch Lomond region were compared with one another and with the established records at a Loch Lomond sediment core and as Scottish archival moss collection. Little similarity was observed among the lead concentration and isotopic histories of the tree cores, or between the records of the tree-cores and the sediment/moss records. Sycamore tree ring analysis was also used to investigate the temporal and spatial influence of lead pollution from two areas of former lead mining and smelting. Wanlockhead and Tyndrum, which produced lead with distinctive isotopic signatures. The investigation of lead concentrations and ²⁰⁶Pb/²⁰⁷Pb ratios revealed a waning influence of the mines with both distance and time since cessation of operations. Although general temporal trends of lead pollution in regions close to large point sources were identified in the tree-ring studies, accurate annual records were not preserved. The contemporary concentration and isotopic composition of atmospheric lead in Scotland was investigated by the analysis of tree bark. Some 85 samples of Scots pine tree bark were collected from throughout mainland Scotland and analysed for lead concentrations and isotopic ratios. The lead concentrations in bark allowed comparison of the relative atmospheric lead concentrations around the country, with higher lead concentration observed in areas of higher population and traffic density, and lower concentrations associated with more remote areas. The ²⁰⁶Pb/²⁰⁷Pb ratios allowed estimations of the source/s of the lead detected in the tree bark. Tree bark was seen to be less suitable for studies of contemporary atmospheric isotopic composition than moss.

Linear alkylbenzene (LAB) is a light non-aqueous phase liquid used as insulating oil in buried electricity transmission cables, from where it may enter soil and groundwater in the event of damage to the cable casing or joints. LAB is also found in the aquatic environment due to its use as a precursor in the manufacture of linear alkylbenzene sulphonate (LAS) detergents, in which it remains as a trace contaminant. LAB is readily biodegraded under aerobic conditions, but because of its use in buried cables, it may be release into anoxic environments where it can persist for some time. Most previous work has focused on the effects of LAB in freshwater and estuarine sediments, with little published data on terrestrial ecotoxicity and fate. LAB has been found to be acutely toxic to the free-living soil nematode. Caenorhabditis elegans, with a 24h LC50 of 5.2 g kg-1 dry weight soil. Aqueous enrichment cultures of organisms from cable oil-contaminated soil show that LAB can be degraded under nitrate-reducing conditions, and that isomeric analysis of the remaining LAB is a good indicator of the degree of degradation. However, soil column experiments and anaerobic respirometry of soil slurries using 14C-labelling LAB do not show appreciable degradation even after 5-6 months. Degradation under iron-reducing, sulphate-reducing and methanogenic conditions has not been demonstrated. Lately, preliminary work using denaturing gradient gel electrophoresis (DGGE) of eubacterial rDNA polymerase chain reaction (PCR) product has provided an indication that changes in microbial diversity do occur in soil following contamination. Furthermore, anaerobic contaminated soils showed rapid LAB degradation upon exposure to aerobic conditions, suggesting that a community of facultative anaerobes capable of degrading the oil had developed.