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Assessment Of Management Policies For Lake Uluabat Basin Using AvswatBulut, Elif 01 December 2005 (has links) (PDF)
This thesis assesses phosphorus loads and management practices to control nutrient transport to Lake Uluabat. It analyzes nonpoint sources of pollution, especially agricultural pollution, throughout Uluabat Basin (watershed). AVSWAT (ArcviewTM Interface of Soil and Water Assessment Tool 2000) was used in determination of phosphorus and sediment loads to Lake Uluabat. Contribution of soluble phosphorus (SOLP) loads from agricultural sites was discussed. Seven scenarios were applied through watershed area to see effects of fertilizer and irrigation application rates, landuse changes, point source and watershed inlet loads on phosphorus loads.
Calibration of the model was performed annually due to lack of data. First stream flow, next sediment and finally nutrient (SOLP) was calibrated at two gages. At the first gage, simulation results were satisfactory in terms of Nash-Sutcliffe Efficiency (ENS) and percentage deviation between observation and simulation values (Dv). ENS values for stream, sediment and SOLP were > / =0.99. Dv values for stream, sediment and SOLP were < / ± / 1%. At the second gage, after calibration, following values were obtained for ENS and Dv: Stream flow - ENS=0.75, Dv< / 10% / sediment - ENS=0.71, Dv=25% / SOLP - ENS=0.55, Dv< / 20%.
It was concluded that agricultural sites were among major contributors of phosphorus load to Lake Uluabat. SOLP load to lake was about 4.0 gP/m2/year, greater than the target value of 1.0 gP/m2/year (DHKD, 2002).
Scenario results showed that removing agricultural lands around Lake Uluabat and decreasing fertilizer application rates were necessary to reduce SOLP loads to lake. Moreover, phosphorus load from Emet and Orhaneli Watersheds seemed significant.
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Reconciling conservation and development in Madagascar's rapidly-expanding protected area systemGardner, Charlie J. January 2014 (has links)
The creation and management of protected areas is our principal approach to conserving biodiversity worldwide. Management and governance models for these diverse institutions have become more pluralistic in recent decades, moving away from the traditional exclusionary protected area model that has proliferated historically. Indeed, most new protected areas are being established for ‘multiple-use’ and, therefore, permit a range of human livelihood activities to occur within their boundaries. However, we know little about how such sites can be effectively managed. In this thesis, I use an interdisciplinary mixed-methods approach to investigate the implementation of new multiple-use protected areas in Madagascar. Madagascar is a global conservation priority characterised by high levels of endemism, and has a largely forest-dependent biota. Since most of the human population is rural and dependent on natural resources for subsistence and income to differing extents, the expanded protected area system is managed for both conservation and socioeconomic goals (poverty alleviation and development). However, these objectives may be conflicting since human resource use can be a significant driver of biodiversity loss. I begin by examining trends in new protected area establishment at the nationwide-level to generate insights into protected area categorisation, and the role of natural resources and protected areas in poverty alleviation. I then consider the impacts of forest use on biodiversity, through a literature review and empirical study of bird and reptile communities across a degradation gradient. The findings indicate that habitat change arising from forest use may impact the high-value, endemic component of the fauna most negatively. In addition, I develop a simple index to enumerate the conservation value of different species. This is then used to determine how degradation influences the conservation value of exploited habitats, as well as assessing if the index is a suitable tool that can be used to prioritise conservation investment across a portfolio of sites. Finally, I seek to understand the drivers of natural resource use by rural communities within the Ranobe PK32 protected area, and discover that both bushmeat hunting and charcoal production are fallback activities or supplements to other livelihoods. The evidence collated in the thesis, derived from both ecological and social perspectives, suggests that managing new protected areas in Madagascar for conservation and development is overambitious, and that, at least in forest areas, management cannot be optimised towards both goals simultaneously.
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Assessing the role of intertidal seagrasses as coastal carbon sinks in ScotlandPotouroglou, Maria January 2017 (has links)
Seagrasses are marine foundation species that form ecologically important habitats in coastal areas around the world. They provide a range of ecosystem services, including coastal protection and the recently recognised large contribution to global carbon sequestration and storage. To date, the majority of published studies on the aforementioned ecosystem services is limited to specific geographic regions and seagrass species. This PhD study attempted to explore and provide the first evidence, to the best of our knowledge, on the role of Scottishseagrasses as carbon sinks and sediment stabilisers. In 2013, shoot dynamics of Zostera noltii plots were monitored biweekly and seasonally in the Forth estuary and digital images of the surveyed plots were taken for the development of a remote sensing technique which would accurately estimate the vegetation cover. In 2014, sediment samples from vegetated and unvegetated plots within beds of Z. marina and Z. noltii were collected from all the major estuaries along the east coast of Scotland, from the Firth of Forth in the south to Dornoch Firth in the north. Samples were analysed for organic matter, organic carbon, radionuclides 210Pb, 137Cs and 241Am, and δ13C in order to determine the organic matter and organic carbon density, longevity and sources of carbon respectively. To explore the role of seagrass in sediment deposition and stability, surface elevation was measured monthly in seagrass plots and bare sediment in the Forth estuary over two years. The results and main mechanisms underlying these findings are reported and discussed in detail in each chapter. In short, the proposed method based on digital images provided estimates of seagrass coverage that are more accurate than observers' estimates, with some constraints when macroalge and/or extreme light are present. Intertidal seagrass meadows in Scotland showed significantly enhanced carbon storage compared with bare sediment. Seagrass plots contained variable quantities of carbon in their sediments with species composition having a significant effect on carbon stocks, whereas depth and seagrass abundance had no effect on carbon stores. Despite their small above-ground biomass Scottish seagrass plots had a strong influence on sediment deposition and prevented erosion. Further research is needed to understand what factors drive large carbon sequestration and storage at some sites, thus contributing policy-relevant information on the prediction of the seagrass carbon hot-spots. Also, long-term datasets on surface elevation change are important in order to understand the effect of all the processes involved on sediment deposition in seagrass beds.
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Ecology and ecophysiology of social structure and population dynamics in bats (Vespertilionidae)Fairless, Louise January 2013 (has links)
Worldwide, bats are in decline with populations under threat from many pressures, including habitat loss, disease and climate change. A detailed understanding of bat social structure and population dynamics is needed to understand and tackle this decline. Yet despite bats representing around twenty percent of all mammalian diversity, they are underrepresented in life history studies, restricting our understanding of social associations, spatial patterns and mating systems for many species. This, in turn, inhibits efforts to conserve species and restricts interpretation of their population dynamics. This study, therefore, aimed to analyse the ecology of social structure and population dynamics using long-term ringing data from several British bat species: Natterer’s bats (Myotis nattereri), brown long-eared bats (Plecotus auritus), Pipistrellus spp. (P. pipistrellus and P. pygmaeus) and Bechstein’s bats (Myotis bechsteinii). Analysis of long-term data of M. nattereri and P. auritus revealed that bats maintain long-term associations persisting over several years. Spatial patterns revealed high fidelity to roost sites. However, on occasions when bats were disturbed during ringing, their dispersal patterns suggested that bats possess a wide knowledge of alternative roost sites which may facilitate relocation following habitat or climate change. Analysis of population dynamics and social structure of three sympatric species (M. nattereri, P. auritus and Pipistrellus spp.) revealed that social systems vary between species and seasons. Large roosting groups were reported for M. nattereri and P. auritus. Males were found to roost with females both pre- and post-parturition, however populations were female-biased for both species. Solitary male Pipistrellus spp. found pre-parturition were joined by an influx of predominantly new adult females for the formation of mating groups post-parturition. There was no preference for roosting in boxes facing North, South-east or South-west for any species. Roosting groups of M. nattereri persisted from pre- to post-parturition whilst the abundance of P. auritus found in boxes post-parturition was low, suggesting alternative roosting behaviour for this species post-parturition perhaps due to increased activity at swarming sites. Increasing population trends were reported for M. nattereri and Pipistrellus spp. whereas the pre-parturition population of P. auritus showed a moderate decline, the cause of which requires further investigation. Survival analysis revealed female-biased survival rates for M. nattereri and P. auritus. Cohort variation in juvenile survival was found in female M. bechsteinii whereby high rainfall during the lactation period and an additive effect of high population density resulted in lower survival. Age of first reproduction varied between one and five years for this species, but did not vary between cohorts with the majority of females reproducing for the first time aged two years. Furthermore, an ecophysiological field study revealed no effect of social structure or roost microclimate on the metabolic rates of free-ranging M. nattereri. However, low metabolic rates indicated torpor was frequently used both pre-and post-parturition. The results of this study suggest that future studies on population biology should take an integrated approach incorporating aspects of both ecology and ecophysiology for the conservation of a species, especially in the face of climate change.
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Greening academia : developing sustainable waste management at UK higher educational institutionsZhang, Na January 2011 (has links)
Dealing with municipal solid waste has become a problematic issue in the United Kingdom (UK). With actions to mitigate the potentially adverse impacts of climate change debate and space for, and costs of, landfill becoming critical, a landfilldominated strategy is no longer acceptable. In this context, the attitudes and behaviour of young adults, particularly university students, who often have little experience of taking responsibility for waste management activities, have not been studied in great detail. Since the 1960s, the UK higher education system has expanded six fold to >2.4 million students. The overall production of waste at Higher Education institutions (HEIs) is therefore very large and presents significant challenges as the associated legislative, economic and environmental pressures can be difficult to control and manage. Therefore, a comprehensive research focusing on university students is urgently required. Changing the way HEIs deal with their waste is an important issue because of fast-changing legislation and increasing costs. The solution is a new approach to waste management: a revolutionary change in the way that HEIs think, the way HEIs act and the way HEIs handle their waste. This has massive implications for the Higher Education (HE) sector. It means developing extensive institution-wide infrastructure to provide greater flexibility and user-centric solutions to suit the need of students and staff. It also means that HEIs work together and potential collaboration between HEIs and Local Authorities (LAs) to maximise resource efficiency, meet future legislative requirements and achieve their corporate responsibilities and commitments. This thesis reports on a study of waste management practices at HEIs in the UK. The issue was approached from both a theoretical and a practical standpoint. The study used the University of Southampton (UoS) as a case study and examined how waste recycling projects can be developed effectively using infrastructure, service provision and behavioural change techniques as part of a wider research programme investigating waste management in medium- and high-density housing. The study clearly showed that there was potential for significantly improving reuse and recycling at university halls of residence (HoR) and that more convenient and higher quality infrastructure and service provision resulted in higher recycling rates. Furthermore, students have lifestyles that impact significantly on waste arisings and consequently on waste management operations at HoR (and probably at HEIs and student-dominated residential areas). For schemes to be successful at HEIs, they must be based on a thorough understanding of students’ recycling behaviour, and their perceptions of the barriers to recycling. The key to unlocking behaviour change lies in the provision of appropriate infrastructure and effective service provision alongside a targeted behaviour change programme. Mass media coverage especially the Internet has a rising influence on university students’ environmental knowledge while environmental education at school has become the secondary source of information. The results also revealed that university students possessed less knowledge than they believed which makes informative behavioural interventions a vital component of effective recycling schemes at HEIs
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An investigation of recalcitrant organic compounds in leachatesYunus, Anika January 2009 (has links)
Recalcitrant organic compounds remain a key challenge in landfill leachate management as they are resistant to microbial degradation and have potential to damage the water environment. Conventional leachate characterisation methods are time consuming and limited by their inability to provide compositional analysis. This research therefore investigates the characteristics of recalcitrant organic compounds in leachates and undertakes a feasibility study of the possible use of UV absorption and fluorescence spectroscopy for a rapid and economical compositional analysis of recalcitrant organic compounds. Two laboratory experiments are carried out in this regard. In one experiment, a laboratory scale aerobic biodegradation is carried out on four untreated and two treated leachate samples collected from two UK MSW landfills (Pitsea and Rainham), and leachates are characterised using conventional methods (COD and DOC) as well as UV absorption and fluorescence spectroscopy. It is found that the leachates which have low organic content are easily biodegradable whereas the leachates which have high organic content are not easily biodegradable. UV and fluorescence spectroscopy allow compositional analysis of recalcitrant organic compounds and show that humic and fulvic compounds are the key components of the recalcitrant organic compounds. A rapid biodegradability assessment of different leachates using these novel techniques is in agreement with conventional method showing that a rapid characterisation of leachates using spectroscopic methods is feasible. It is also found that organic compounds in these leachates are aromatic in nature and the leachates containing large amounts of aromatic compounds, condensed aromatic structures are difficult to degrade. In another experiment, the influence of the solid waste component on the development of recalcitrant organic compounds in leachates is investigated by carrying out an anaerobic biodegradation experiment for fresh waste, composted waste, newspaper waste and synthetic waste. Composted waste contributes significantly to the development of the recalcitrant compounds due to the removal of readily biodegradable organic compounds during composting and hence the increased proportion of biologically resistant compounds during the subsequent anaerobic biodegradation. Newspaper waste also contributes significantly to the presence of recalcitrant organic compounds due to the relatively less resistant cellulose and high lignin present in this waste. This research validates the application of UV and fluorescence spectroscopy for rapid on-site monitoring of landfill leachates that would help scientist and engineers to assess leachate quality, identify various organic compounds and to optimise leachate treatment processes. The analysis performed on Pitsea and Rainham leachates is a promising step towards developing a database of representative information of characteristics of recalcitrant organic compounds in leachates for different UK landfills. This research also provides an understanding of the composition of leachates from different wastes and it can be conclude that disposals enriched with composted and newspaper waste would favour the development of leachates with high concentrations and condensed aromatic structures of recalcitrant organic compounds in a landfill system
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Spartina anglica population and environmental studies within the Solent salt marsh systemTsuzaki, Toru January 2010 (has links)
The thesis examines the possible causes of decline of Spartina anglica marshes along the south coast of Britain with emphasis on the Solent marshes. The study shows that although there may be some genotypic differences between S. anglica gathered from sites in Britain. The disparities are not large enough to explain the significant differences in morphological vigour of S. anglica observed in the field. It concludes that the discrepancies observed in the field are the result of phenotypic differences resulting from environmental factors. The work shows that in the S. anglica marshes of the south coast, anaerobic soil conditions prevail with impeded drainage being the most likely cause of the dwarf growth forms and lack of re-colonisation of pans and mudflats observed in the field. The thesis concludes that the ultimate demise of the S. anglica marshes of the south coast of England is the result of frontal and creek erosion of the mature marsh and the failure of S. anglica to establish itself on the newly exposed sediments of the foreshore. When S. anglica establishes itself in a flood /ebb neutral zone of an estuary, it changes the bathymetry to that of ebb dominant morphology. As a result eroded sediment is swept away with the outgoing tide. Furthermore, S. anglica is then unable to recolonise the exposed foreshore sediments because of its low redox potential resulting from poor permeability which is the consequence of the of historic overburden pressure of a once colonising marsh.
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Thermochemical hydrogen production from the sulphur-iodine cycle powered by solar or nuclear sourcesStone, Howard Brian James January 2007 (has links)
Since mankind's adoption of fossil fuels as its primary energy carrier for heating, elec- tricity and transportation, the release of greenhouse gases into the atmosphere has increased constantly . A potential replacement energy carrier is hydrogen. Current industrial techniques for dissociating hydrogen from its common substances are con- ventionally reliant on fossil fuels and thus greenhouse gases are still released. As a mechanism to develop a hydrogen economy current industrial techniques will suffice; however, a long-term sustainable solution to hydrogen mass production that does not release greenhouses gases is desired. The United States of America Government be- lieves that the Sulphur-Iodine thermochemical hydrogen production cycle, thermally powered by a nuclear source, is the most likely long-term solution. A critical part of the Sulphur-Iodine cycle is the point of interaction between the thermal source and sulphuric acid used within the cycle. A novel bayonet heat exchanger made from silicon carbide is theoretically applied to the point of interaction. Through a combination of experiments and theoretical modelling, the bayonet heat exchanger is characterised. The bayonet model is then modified to simulate the intended nuclear reactor favoured by the United States Department of Energy. In addition, the bayo- net heat exchanger is analysed for a solar thermal application. An advanced design of the bayonet is also presented and theoretically analysed for its increased thermal efficiency.
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Organotin and osmoregulation : quantifying the effects of environmental concentrations of sediment-associated tri-n-butyltin and triphenyltin on osmoregulatory processes in the European flounder Platichthys flesus (L)Hartl, Mark G. J. January 2000 (has links)
The disruption of physiological and morphological aspects of osmoregulatory processes in freshwater-adapted 0-group European flounders, Platichthys flesus (L.), caused by exposure to environmental concentrations (150 ng triorganotin g"1 dry weight sediment) of sediment-associated tri-o-butyltin chloride (TBTCl) and triphenyltin chloride (TPhTCl), was examined and quantified. Radiotracers were used to measure hydromineral fluxes, the water balance and passive sodium efflux of chronically (35 days) exposed fish. The water permeabilities of exposed flounders varied during the course of the experiment and were significantly lower than the corresponding controls, that did not change significantly with time. It was found that the maximum change in water permeability of TBTCl- and TPhTClexposed fish occurred after 14 days and 21 days, respectively; thereafter there was an increase towards control values, suggesting adaptation to compensate for the effects of the organotin exposure. Drinking rates increased significantly in both organotin groups but urine production rates did not change. The effects of organotin exposure on the passive sodium efflux and Na+/K+-ATPase activity showed an inverted relationship in the TBT group, where the Na7K+-ATPase activity was reduced and the passive sodium efflux was increased. TPhT had no inhibitory effect on Na7K+-ATPase activity and the passive sodium efflux increased only gradually. The overall effect of these changes in these components of hydromineral regulation was to reduce the mean blood osmolalities of the organotin groups compared to the control values. The effects of chronic exposure to sediment-associated triorganotin compounds during sea water adaptation was examined and quantified by measuring the active sodium efflux, Na+/K+-ATPase activity and structural changes to the gill epithelium usually encountered in euryhaline fish during adaptation to sea water. Following the transfer to sea water, the Na+/K+-ATPase activity and the active sodium efflux were decreased in the TBT group but increased significantly in both the TPhT and control groups. Similarly, the morphological changes to the gill epithelium, involving chloride cell distribution, associated with sea water adaptation, took place in the control group and only partially in the TPhT group but were significantly inhibited or delayed in the TBT group. The exposure to organotin caused the mean blood osmolalities in fish of the TBT and TPhT to rise beyond the expected values that were observed in the control group. The results presented in this study lead to the conclusion that tri-tt-butyltin chloride and triphenyltin chloride in sediments are capable of significantly disrupting both the physiological as well as morphological components of osmoregulatory functions of an estuarine fish, at concentrations currently found in local sediments.
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Urban carbon and energy analysis : calculation of energy flows and emissions from residential housing clusters and assessment of sustainable energy optionsPapafragrou, Anastasios January 2010 (has links)
In the UK, the domestic sector accounts for around 30% of fuel-use and energy related carbon emissions, and therefore has the potential to deliver significant reductions in carbon dioxide emissions. The purpose of this work is to form and examine various heat and electricity supply scenarios at the street-level and identify which of these scenarios offer the most potential to reduce consumption of resources and carbon dioxide emissions. The path to realisation of a reduction in carbon emissions from the domestic sector incorporates three consecutive steps: (1) saving energy, (2) use of renewables and (3) use energy as efficiently as possible, including fossil fuels. In reality, there is a strong interaction between all three steps and often they take place simultaneously. The first two steps tend to minimise the use of fossil fuels, but not to eliminate them. In this work it is recognised that in mature urban regions fossil fuels cannot be readily displaced completely, but can be used in a more efficient way. This research considers what can be achieved by applying at or near to market technologies at the street level microgrid scale, such as Combined Heat and Power (CHP). The renewable energy technologies considered were photovoltaics (PV) for electricity generation, solar thermal for domestic hot water heating and ground source heat pumps (GSHP) for space heating. For the development of the models, the transient simulation package TRNSYS was used and a residential area in Southampton that represents a typical UK area, was chosen as a case study. The notion of combining a number of houses to form a local microgrid proved to be beneficial for all the technologies examined in this research. It was shown that renewable energy microtechnologies can improve their carbon performance up to 10% when operating as a microgrid, whilst estimated benefits were even greater for CHP systems. Parallel operation strategies were also investigated and it was shown that they have the potential to deliver further savings from microgrid schemes. Microgrids, although their high capital costs, were estimated to have better financial performance compared with the single house level for many of the cases examined. Increased generation and lower heating demand were the key outcomes due to the impact of change in climate
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