Snow accumulation has potential climatological, hydrological and ecological impacts at a global scale. Satellite passive microwave radiometers have the potential to provide snow accumulation data with a historical record of over 30 years, however, current data products contain unknown uncertainty and error. Snowpack stratigraphy is the spatial variation in snowpack properties caused by the layered nature of the snowpack. Snowpack stratigraphy influences the accuracy and increases uncertainty in simulations of microwave emission from snow which in turn increases uncertainty in satellite derived estimates of snow water equivalent using microwave radiometers. Two methods were developed to help better quantify snowpack stratigraphy. An improved technique for characterising snowpack stratigraphy within a snow trench was developed. Secondly a new method was developed to quantify the density of ice layers that form in snowpacks with known error and uncertainty. Snowpack stratigraphy was characterised using the improved technique across the Trail Valley Creek watershed in the Canadian Northwest Territories. Two 50 m trenches and eleven 5 m trenches were dug across the range of landcover types found in the watershed. This dataset allowed layer boundary roughness to be characterised and the properties of snow layers to be mapped with an unprecedented level of accuracy. Ice lens density was measured 60 times at three locations in the Arctic and midlatitudes at locations with coincident ground based radiometer measurements. The impact that accurate parameterisation of density has on modelled estimates of brightness temperature was quantified. Simulations of microwave brightness temperatures were conducted using snow emission models at all locations. The output of these simulations, and comparison to ground based observations where available, allowed for the characterisation of variability in brightness temperature simulations caused by stratigraphic heterogeneity. The findings presented in this thesis will inform research aiming to better characterise the satellite error budget. Improvements in this area helps improve global snow mass and snow accumulation estimates.

Nicaragua faces tremendous problems in relation to environmental and social conditions as well as continuing conflicts over access to natural and economic resources. The loss of forests and other essential eco-systems, the extinction of unique species, the degradation of soils and farmland, poverty, ill heath, exploitation and great inequalities of wealth and power remain on-going processes and essential characteristics of Nicaragua. These conditions represent an environmental crisis that threatens the country's ecological and social well-being. The thesis considers the historical causes of the environmental crisis looking at the impact of the introduction of particular political and economic structures, the development of the dictatorship of Somocisnio in Nicaragua and the impact of US hegemony in the region. It further considers why the strategies adopted by successive administrations and international organisations have failed to adequately address Nicaragua's environmental problems. The need for radical political and economic change as a means to address the underlying structural causes of environmental degradation is investigated in relation to Nicaragua. However, the examination of the effects of the Sandinista Revolution in Nicaragua is also used to reveal important insights into the impact of structural change on the environment and the necessity to include other, reformist components in any solution. Post-Revolutionary strategies and the current emphasis on NGO and community based sustainable agricultural programmes are examined in detail to evaluate the importance of this approach for environmental protection. In addition to an examination of the effectiveness of the strategies of the post-revolutionary state, a case study analysis of Programa Campesino-a-Campesfno, the most prominent and successful example of the new, community-based initiatives, is used to illustrate the generic problems and opportunities present in the new 'paradigm' of localism and sustainable agriculture. While these new initiatives may provide key components to a solution, the study considers whether by themselves, they have the capacity to address the underlying causes of degradation. The study concludes that the environmental crisis is primarily a result of the particular development model that has arisen in the region since the colonial conquest, and which has facilitated the development of a system based on the highly unequal distribution of resources and power. Consequently, the causes of the crisis are essentially structural in nature, requiring that radical changes be made to the political and economic structures of society. However, the lesson of Nicaragua's Sandinista Revolution, during which environmental degradation continued despite a series of structural and socio-political changes, indicates that structural changes do not of themselves, guarantee environmental sustainability. Equally, the limitations of programmes such as Campesino-a-Campesino reveal that a reliance on agroecological and community-based methodologies is also flawed. Therefore, progress towards social and environmental justice in Nicaragua requires a combination of radical changes to political and economic structures, alongside the use of ecologicalbased agricultural and land management practices. This means that inequalities in land and natural resource ownership are addressed in order to provide sustainable economic and ecological systems within which Nicaraguans can attempt the longterm management and protection of their environment. The introduction of these new practices must include the participation and skills of local populations in any process of change. Redistribution of wealth and resources must be accompanied by a redistribution of power so that the control and development of these changes and initiatives, develop from, and reside in, the hands of ordinary Nicaraguans.

New climate change projections for the UK were published by the United Kingdom Climate Impacts Programme in 2009. They form the 5th and most comprehensive set of predictions of climate change developed for the UK to date. As one of main products of UK Climate Projections 2009 (UKCP09), the Weather Generator, can generate a set of daily and hourly future weather variables at different time periods (2020s to 2080s) and carbon emission scenarios (low, medium and high) on a 5 km grid scale. In a radical departure from previous methods, the 2009 Projections are statistical-probabilistic in nature. A tool has been developed in Matlab to generate future Test Reference Year (TRY) and Design Reference Years (DRY) weather files from these Projections and the results were verified against results from alternative tools produced by Manchester University and Exeter University as well as with CIBSE’s Future Weather Years (FWYs) which are based on earlier (4th generation) climate change scenarios and are currently used by practitioners. The Northumbria tool is computationally efficient and can extract a single Test Reference Year and 2 Design Reference Years from 3000 years of raw data in less than 6 minutes on a typical modern PC. It uses an established ISO method for generating Test Reference Year data and an alternative method of constructing future Design Reference Years data is proposed. Fifteen different buildings have been identified according to alternative usage, thermal insulation, user activity and construction details. Besides these variants, the buildings were chosen specifically because they either exist, or have received planning consent and so represent ‘real’ UK building examples. Two investigations were then carried out based on the 15 case study buildings. The first involved applying TRYs generated for London, Manchester and Edinburgh for a variety of carbon emission scenarios at time horizons of 2030, 2050 and 2080. The TRYs were developed into a weather data format readable by the EnergyPlus energy simulation program to simulate summertime internal comfort (operative) temperatures, cooling demands and winter heating demands. All results were compared with a control data set of nominally current weather data, together with the same results produced using the alternative weather data generators of Manchester University, Exeter University and the CIBSE FWYs. Results revealed a good agreement between the various methods and show that significant increases in internal summer operative temperatures in non-air-conditioned buildings can be expected as time advances through this century, as well as increased air conditioning cooling energy demands and small reductions in winter heating energy demand. The second investigation involved generating time series of design internal peak summertime operative temperatures, design cooling demands and design winter heating demands for the same conditions as the first investigation. The results were then used to develop a simplified estimation method to predict future design cooling loads using multiple regressions fitting to selected data from the DRY simulation inputs and outputs. The simplified estimation method forms a useful tool for estimating how future cooling design loads in buildings are likely to evolve over time. It also provides a basis for designers and practitioners to determine how buildings constructed today will need to be adapted through life to cope with climate change.

Life-history features of terrestrial mammals in the southern African subregion were explored in an attempt to identify the factor(s) that may influence the evolution of common mammalian life-history patterns within this subregion. Allometry and phylogeny were found to underly most of the variation observed in life-history features. Residual variation was considered and age at maturity, gestation period and litter size emerged as additional features influencing life-history patterns. Southern African mammals could generally be arranged along a theoretical r-K continuum with small mammals having relatively short developmental periods and relatively large litter sizes represented at one extreme and large mammals having relatively long developmental periods with relatively small litter sizes at the opposite extreme. However, the carnivores did not conform to this expected general gradient suggesting that they may be an exceptional order as far as their life-histories are concerned. / Dissertation (MSc)--University of Pretoria, 2011. / Zoology and Entomology / unrestricted

Significant climate and vegetation changes have occurred during the Cenozoic era (66 Ma - present), particularly in the southern-high latitudes. The terrestrial record in Antarctica is fragmentary and available successions are limited due to remoteness and thick ice cover. The aim of this study is to provide new insights into what changes occurred during available successions in two epochs of the Cenozoic, the Holocene (11.7 ka - present) and the Oligocene (33.9 - 23.03 Ma) in the sub- Antarctic and East Antarctic region. This thesis begins on South Georgia Island in the sub-Antarctic region, where a 5.8-m long high-resolution pollen record covering the last 7000 years was taken from Fan Lake on Annenkov Island. Palynological and sedimentological analyses indicated warm late Holocene conditions between 3790 and 2750 cal. yr BP transitioning to a cooler and wetter environment. Increases in long-distance pollen grains from South America between c. 2210 and 1670 cal. yr BP and after 710 cal. yr BP suggested strong Southern Hemisphere Westerly Winds over South Georgia during the late Holocene. These results question previous studies which proposed highest wind intensity during the warmer mid-Holocene climate optimum. Little is known about how Antarctic vegetation changed from the subtropical and temperate rainforests of the warm Eocene to the cold tundra shrubs which dominated during the Miocene. Oligocene assemblages from site U1356 Wilkes Land, East Antarctica (IODP 318) covering ~33-30 and ~25-23 Ma are characterised by lowland fragmented cool forests and tundra/shrubland. Temperature reconstructions derived from the fossil pollen assemblages using the Coexistence Approach suggest mean annual temperatures between 5.8-13.7°C during the Oligocene. A decline in warmer taxa (e.g. Dacrydium praecupressinoides and Phyllocladidites mawsonii) and high abundance of reworked sporomorphs and Leiosphaeridia sp. indicate the progression towards cooler/glaciated conditions between ~25-23 Ma. The Wilkes Land assemblage shows a warmer palaeoflora compared to previous Antarctic palaeorecords and the regional vegetation differences may be explained by the palaeotopography of Wilkes Land which has a lower altitude and reduced glacial influence in contrast to other sites. After the formation of the cryosphere at the Eocene-Oligocene transition glacial reworking is a major component in Antarctic marine and terrestrial sedimentary deposits. Uncertainty as to whether Cenozoic sporomorphs were reworked or in situ has previously restricted palaeoenvironmental reconstructions. This thesis presents a new red fluorescence approach to differentiate reworked and in situ sporomorphs over relatively short geologic timescale (e.g. Paleogene and Neogene). The establishment of an in situ palaeoflora assemblage from Wilkes Land enables a robust interpretation of Oligocene environments without the influence of reworking.

This thesis examines the implementation of air pollution control at the local level within the UK. Focusing upon the local air pollution control regime (LAPC) that is regulated by local authorities under the provisions of Part One of the Environmental Protection Act 1990, the research assesses whether this system has been effective in controlling localised emissions from industrial processes. To place the research in context, it essentially evaluates the implementation of LAPC with reference to its main objectives: to reduce industrial emissions and improve local air quality, to provide greater clarity and certainty for business and to allow the public greater access to local environmental information. The methodology adopted to undertake the research was based upon grounded theory and naturalistic inquiry. As such, the research programme was structured in phases where initially, essential baseline data was collected on the LAPC system. This quantitative data provided the foundations from which more detailed qualitative work was undertaken in the field in subsequent phases of the research. This allowed the research to build towards theory utilising an emergent, yet structured research design. As the research progressed, a range of complementary methods were used to collect data about the LAPC system. Initially, the research critically evaluated the major Reports that had been written on LAPC in order to establish benchmarks from which implementation of the LAPC system could be assessed. To keep the research within defined limits, a case study approach was adopted, using Lancashire as the case study area. Under the first phase of the research a questionnaire was used to survey the process operators within the region in order to collect baseline information about their processes and to obtain their views and perceptions of the LAPC system. Under the second phase qualitative research was carried out in the field. This involved detailed, semi-structured, faceto-face interviews with the process operators and the DETR and examination of documentary evidence within the Public Registers held by Lancashire's local authorities. The phased approach allowed the research to explore progressively deeper into the key areas associated with the implementation of the LAPC system. In particular, the research examined local authority enforcement and administration of the LAPC system to assess their regulatory performance and to determine the strategies they adopt to achieve compliance. The research also focused upon the process operators to assess their capacity to comply with the duties and responsibilities placed upon them under LAPC. The work offers a new perspective as it focuses upon both regulators and operators alike and examines their performance from the outset of LAPC to its closing stages. The research findings allow conclusions to be drawn on the relationship that exists between these "stakeholders" and the regulatory conditions that exist within the system. The research findings suggest that local authorities and process operators have had difficulty in discharging their duties under the LAPC system. For various reasons, the capacity of the regulators and the operators to achieve compliance has been compromised. The difficulties that the stakeholders have faced in striving to come to terms with the LAPC system have influenced their compliance strategies and affected the relationship that exists between them. This research identifies and examines these difficulties and assesses their performance under such conditions.

Earthworms are considered very important soil organisms, greatly influencing soil function through their feeding, burrowing and casting activities, e.g. comminution and incorporation of litter into soil, building and maintenance of soil structural porosity and aggregation, promoting changes in microbial communities and activities and influencing plant growth. Although research on earthworms is increasing rapidly, there is still inadequate knowledge of the basic biology and ecology of even common species, such as Lumbricus terrestris. This study aimed to examine aspects of adult, immature and hatchling L. terrestris dispersal, distribution and intraspecific interactions through a number of laboratory and field experiments. Results demonstrated that population density can significantly affect dispersal in L. terrestris. Intraspecific competition for food resources and space in combination with the need to secure mating opportunities interact to produce regular patterns in the horizontal distribution of individuals, observed at the scale of I m 2. Burrow reuse by offspring and other conspecifics was observed, in addition to permanence in distribution of L. terrestris over short periods (1 year). Intraspecific competition between adults (parents or not) and hatchlings/juveniles intensified as the latter grew in size. However, observations of cocoon deposition by adults in distinct locations within side burrows, could represent a form of "parental investment". Results from this study could assist in identifying some of the factors that influence L. terrestris population dynamics, however further research is required to fully understand how their combined effect may influence the behaviour of this species in natural environments.

Ice plays an important role in hydraulic processes of rivers in cold regions such as Canada. The formation, progression, recession and breakup of river ice cover known as river ice processes affect river hydraulics, sediment transport characteristics as well as river morphology. Ice jamming and break up are responsible of winter flash floods, river bed modification and bank scour. River ice cover monitoring using terrestrial images from cameras installed on the shores can help monitor and understand river ice processes. In this study, the benefits of terrestrial monitoring of river ice using a camera installed on the shore are evaluated. A time-lapse camera system was installed during three consecutive winters at two locations on the shores of the Lower Nelson River, in Northern Manitoba and programmed to take an image of the river ice cover approximatively every hour. An image analysis algorithm was then developed to automatically extract quantitative characteristics of the river ice cover from the captured images. The developed algorithm consists of four main steps: preprocessing, image registration, georectification and river ice detection. The contributions of this thesis include the development of a novel approach for performing georectification while accounting for a fluctuating water surface elevation, and the use of categorization approach and a locally adaptive image thresholding technique for target detection. The developed algorithm was able to detect and quantify important river ice cover characteristics such as the area covered by ice, border ice progression and ablation rate, and river ice break up processes with an acceptable accuracy.

This thesis considers the methodologies and organisational impacts of Environmental Reviews and Environmental Management Systems in Local Authorities, Universities and Conservation organisations. It assesses the practical impacts of these tools, identifies elements of good practice and discusses the organisational and political factors which affect the success of environmental management activity in these organisations. Chapter 1 describes the growth of global, European and national policy initiatives aimed at minimising environmental degradation and delivering sustainable development and the subsequent development of environmental strategies and environmental management tools in organisations. Chapter 2 discusses environmental management activity in Local Government in the context of Local Agenda 21, using the results of a survey of environmental management techniques in local authorities and a case study of Lancashire County Council. These findings are discussed in the context of changes to local government organisation in the UK and in relation to local government management theory. Chapter 3 considers environmental management activity in Universities in the context of institutional performance using the results of a survey of approaches to environmental management in Universities and a case study of environmental management in the University of Central Lancashire. These findings are then considered in relation to changes in the orgamsation of the Higher Education Sector in the UK and in the context of university management theory. Chapter 4 considers the use of environmental management techniques in the Conservation sector in the context of Local Agenda 21, using a survey of conservation organisations and a case study of The National Trust's environmental management strategy. These findings are then discussed with regard to changes occurring in the management and funding of NGOs and quangos in the UK. Based upon the research findings, a number of recommendations are made for successful organisational environmental management strategies and the long term application of these techniques within each of these sectors. These findings are then drawn together in Chapter 5 to identify common methodological, organisational and political factors which affect the success of organisational environmental management strategies and to discuss their potential contribution to sustainable development. An alternative approach to TQM based environmental management is offered for organisations, based upon the elements of good practice identified in the non-profit sector, which include conscensus building, wide participation, and democratic decision making. Within the organisation, this approach closely resembles the Local Agenda 21 process used by local government to consult and empower local communities in sustainable development.

N2 fixation rates for several Virginia salt marshes were determined using in situ acetylene-reduction assays. A control and a chronically polluted oil marsh of the mesohaline Mobjack Bay area were sampled over a 1975-76 annual cycle. N2 fixation occurred in all transects which extended from upper mudflat to the Spartina patens zone. An isolated blue-green algal mat exhibited some of the highest N2 fixation rates. Intertidal sediment N2 fixation was patchy, both spatially and seasonally. However average rates (91.45 μg N/m2/h) compared to the estimated N requirement of the graminoid vegetation indicated a significant contribution to the N budget. Vegetation associated nitrogen fixation yielded higher average rates. N2 fixation rates for Wachapreague high salinity and Yorktown relic low salinity marshes were similar to the mesohaline marshes although blue-green algae fixation seemed to be more significant. The seasonal pattern of mesohaline marsh N2 fixation was positively related to temperature. Light-dark and anaerobic-aerobic experiments support the hypothesis that heterotrophic bacteria are the predominant N2 fixers and that availability of oxidizable substrates contribute to the seasonal pattern. Chronic oil treatment showed little effect on fixation rates with the possible exception of median tidal elevation sediments where summer rates were considerably higher than those of the control. This dissertation is from the Joint Program Degree from the College of William & Mary and University of Virginia and awarded by the University of Virginia.