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The key factor in promoting sustainable fisheries is implementing a sustainable fishing operation that is not only environmentally friendly but also economically viable and socially acceptable. To achieve this, fish resources, fishing technology, and the organisation of fisheries should be managed proportionally. Regarding fishing technology, most of the existing approaches discuss the development of ecologically safe fishing gear but disregard the fishing vessel itself, which inspire this thesis to develop a novel approach focusing on the fishing vessel. Therefore, the main goal is to develop and formulate best practices for sustainable fishing operations, concentrating on small-scale fishing vessels. A case study was conducted in Palabuhanratu, a region with a significant number of small-scale fishing practices, which is typical of many fishing regions in Indonesia and other developing nations. This research investigates four principal types of vessels based in Palabuhanratu, specifically, pelagic Danish seiners, trammel netters, handliners, and lift netter. The selection represents the principal types of operations including activepassive fishing and demersal-pelagic fishing. The research was carried out in four stages. Stage one sought to understand the existing fishing practices, which produced a fishing operation model. Stage two was a sustainability assessment, which elicited the environmental, economic and social impacts of the current operations. Stage three identified the possible measures to improve the existing performance. Stage four formulated best practices for implementing sustainable fishing vessel operations, which resulted in management measures derived from a tradeoff between theoretical principles and potential implementation. The results show that when considering the fishing vessel, passive operations are generally more sustainable than active operations. The research also reveals the importance of trade-off between environmental, economic and social performances when comparing overall sustainability, as no single operation performs well in all elements. In conclusion, this research demonstrates a comprehensive investigation on the performance of small-scale fishing vessel operations. In order to promote sustainable operations, best practice has been formulated by considering the contribution of all sustainability elements proportionally.

The Omani fishery sector is an important source of seafood and makes a significant social and economic contribution to Oman's national Gross Domestic Product (GDP), providing on average 0.55% of Oman's GDP during the period 2007-2015 (MAF, 2015). The Ministry of Agriculture and Fisheries (MAF) has prepared the Oman Fisheries Strategic Plan (OFSP) (MAF, 2012b) for the development of the fisheries sector for the period 2013-2020 through the implementation of 20 projects with investment amounting to about 509.40 million Omani Rial (OMR) (approximately US $1.32 billion). This investment is planned to reach a production target of about 462,000 tonnes of fish annually by 2020, an increase of 27% compared to the current annual rate of increase of up to 2.8%, and is estimated to achieve a direct financial return of OMR 369.60 million (US $ 960 million) at constant prices, and also to provide more than 8,600 direct jobs by 2020. The aim of this study is to investigate the OFSP and evaluate how likely it is that these objectives will be realised in practice. Methods of obtaining secondary and primary data include documentary analysis, participant observation, 44 key informant interviews, ten focus group discussions (the total number of people involved in the focus group discussions (FGDs) was 40) and 92 survey questionnaires. The pilot fieldwork was conducted between August and September 2014 in order to prepare for the main fieldwork. The main fieldwork was conducted between August and October 2015. The key findings show that most of the development projects have been suspended indefinitely, mainly because of the slump in oil prices, lack of private sector investment, and lack of political will to address problems such as widespread non-compliance with fisheries regulations, illegal foreign workers, little stakeholder involvement in decision-making, and bureaucratic governmental institutions. Even if the above problems are solved, four uncertainties were identified that could impact the implementation of the OFSP. First, there is no guarantee that small-scale inshore fishers will retrain to work on offshore larger vessels. Second, there will be environmental impacts on fish stock levels as a result of the expansion of fishing. Third, there is the danger of opening up Oman’s fisheries sector to the forces of globalisation that could expose it to market instability and foreign control. Fourth, the plan does not appear to recognise that wholesale modernization of the fisheries sector could lead to reduced, not increased, employment levels. In short, the results suggest that the likelihood of the OFSP being realised is slim. The study makes several recommendations to the management authority on how to address these issues and contribute to Omani’s sustainable development of the fishery sector. The findings herein have wider implications in highlighting the importance of evaluating strategic plans against realistic achievements.

Laboratory batch and long-term column experiments were conducted to investigate the effects of wood-chip biochar and coal-derived activated carbon amendment on the microbiology of a volatile petroleum hydrocarbon (VPH) - contaminated gravelly sand. First, a stable isotope-labelled mono aromatic compound – toluene was used as a model VPH to gain insights into the mineralization of VPHs by soil microorganisms in the presence and absence of biochar or activated carbon. The biodegradation of a mixture of 12 VPHs was subsequently monitored in batch microcosms over a duration of 6-19 days by measuring headspace CO2 concentration. Further analysis was carried out by characterizing changes in the soil microbial community composition using next generation sequencing techniques – 454 pyrosequencing and Ion torrent sequencing. Increases in the levels of headspace CO2 in contaminated soil batches as compared to live and abiotic controls to which no VPHs were added indicated a stimulation of microbial activity in the batches through VPH addition. By fitting a maximum specific growth rate of 0.6 h-1 (in line with published rates), it was possible to match model predictions of 45CO2 and 44CO2 concentrations with the experimentally determined data. Half-saturation constants of 4.06 x 103 mgL-1, 7.76 x 102 mgL-1 and 1.83 x 102 mgL-1 were predicted for soil, soil & BC and soil & AC respectively, much higher than values reported in the literature. Differences in the half-saturation constant suggests that sorbent amendment affects the microbial ecology, by making microorganisms which can utilize substrates at lower concentrations more competitive. Yield coefficients (g biomass-C relative to g (biomass-C + CO2-C)) compared more closely in the nutrient (N & P) amended soils ranging from 4.83±0.46 in soil and biochar to 7.86±0.72 in unamended soil, than in the batches without nutrients, 4.1±3.1 in soil & BC, 17.7±5.2 in soil and 13.7±4.6 in soil & AC. Sorbent amendment thus reduced yield coefficients, thereby slowing the growth of VPH degrading biomass. Microbial community structure analysis revealed an increase in the relative abundance ranking of members of the genera Pseudomonas, Pseudoxanthomonas, and Arenimonas by up to 32 folds and in the families Nocardioidaceae and Pseudomonadaceae by at least 32 folds in sorbent amended and unamended soil batches and columns compared to their initial soil conditions. Consequently, amending soils with 2% BC or AC changed the biokinetics of VPH degradation by rendering VPHs less bioavailable, but did not appear to have any detrimental effects on the VPH degrading bacteria both in the short- and long-term, and may serve as a sustainable, cost-effective approach for enhancing the natural attenuation of VPHs in soil, thus addressing the challenge of petroleum hydrocarbon contamination.

Energy security is a priority for most countries as a pivot for economic development. However, Nigeria, despite being a major oil producer, is plagued by energy insecurity in addition to long-standing food insecurity. Nigeria spent 4% of its GDP (~ US$5B/year) importing refined petroleum products (RPP) for its transport sector between 2005 and 2009. In addition, an annual average food import of 3 million metric tonnes has existed for almost a decade. To combat these energy and food insecurities, the Nigerian government plans to produce bioethanol from its major staple food (sugar and starch) crops in order to increase its transport fuel supply and ameliorate the negative impacts of the on-going import of motor fuel to its economy; given substantial uncultivated arable land, unemployed labour and suitable climatic and soil conditions. The dilemma between the apparent benefits of biofuels versus its potential impacts on food security needs to be analysed in order to articulate and implement a feasible ethanol policy. This study develops and applies a sectoral Energy-Food Model (EFM) to: 1) analyse the supply capacity of the feedstock and food suppliers (the farmers in Nigeria) for ethanol; 2) estimate the bioethanol production potential in Nigeria; 3) identify the regional potential ‘best’ feedstock; and 4) assess the impacts of the potential feedstock and bioethanol demands and supplies on the national energy and food securities. The programming model is based on farm production data from relevant national agencies and on Nigerian energy supply, food consumption, commodity export and import and commodity prices from international and national official databases such as EIA, FAOSTAT, IMF, World Bank, and Nigerian Bureau of Statistics databases. Results show that Nigeria has the potential to produce sufficient feedstock and food crops required to meet the domestic ethanol and crop consumption requirements without reducing domestic food supply or increasing domestic commodity prices. Further, cassava is identified as the best feedstock for ethanol production in all the regions under current production and price conditions. Domestic ethanol production/supply to the local market for blending would generate and add a gross profit of US$2,725M per annum (including the potential co-products revenue) to national income. Also an annual production of 5.14 billion litres of ethanol from all the regions is feasible, and this can substitute 514 million litres of gasoline (4% of the annual average domestic RPP demand) at 10% ethanol blending, and save about US$36B per annum at US$70.33 per litre of the imported RPP. The changes in labour and land use were substantial, but without associated increase in the prices of labour and land, reflecting existing un- and under-employment and stocks of uncultivated arable land. The impacts of ethanol production from the first generation feedstock on food supply and food prices are practically absent in a country with sufficient land and production resources.

Migratory species undertake prolonged seasonal journeys; monitoring these movements is challenging but can sometimes be achieved by observations that taken locally and, ideally, using remote methods. Amongst the best known examples of migrating fish in Europe, are Atlantic salmon (Salmo salar) and sea trout (Salmo trutta) that migrate between river and seawater. Characteristics of habitat suitability, feeding opportunities, predation, as well as salmonid sensitivity and needs, vary throughout successive stages of their anadromous life cycle. Since the marine stage is the longest but is also challenging to monitor, in-river fish counters are of increasing importance in understanding salmonid patterns in abundance. The original contribution of this thesis lies in the use of modelling techniques to investigate salmonid migration, based on temporal observations produced by an electronic fish counter triggered by salmonid passage, as they return to spawn in the River Tyne. Small scale observation revealed seasonal differences; aggregation behaviour intensified during the middle of the migration season, and explanatory covariates varied in both their effect size and relevance to salmonid abundance. At the population scale, migration was highly driven by annual periodicity, abundance increased with river temperature and there was an NAO effect with a four year lag, underlining the importance of marine conditions to parent population and/or post-smolts. Differences between distinct populations of S. salar and S. trutta appeared related to a species-specific annual periodicity and oceanic conditions as salmonids return (more so for S. salar). State-space models suggested a complex demographic structure for the two species. There was a species identification learning curve that affected the data by 2007. A classification algorithm determined that observations are more likely to be S. salar for larger signal amplitude, within a higher river flow and earlier in the year; characteristics were too similar between the two species to reach a useful classification success rate (69%). The project overall suggests specificities relating to both species and age-class that cannot be addressed in depth with the collected data; emerging limitations and recommendations are discussed.

Wind energy, like all renewable energy production, is a sustainable resource with a far lower carbon footprint than the burning of fossil fuels and consequently plays a role in mitigating climate change. There has been a rapid rise in its use over the last 15 years. However, there are concerns regarding the potential effects of wind turbines on wildlife, especially birds and bats. Potential effects include disturbance through direct or indirect habitat loss, or fatality through collision with turbine blades. First, I investigated the potential of using existing bird monitoring data collected by Environmental Impact Assessments (EIAs) and post-construction monitoring for developing an evidence base for the impacts of wind turbines on bird populations. As EIAs are required for wind farms to predict and mitigate potential negative effects, vast amounts of data are gathered by wind farm companies but subsequently not used to assess the effects, due to the associated logistical issues of obtaining these data (despite being officially available in the public domain). Using data from seven wind farm sites, I found that lekking black grouse (Tetrao tetrix) that were initially close to the wind turbines (up to 500m) moved locally after wind farm construction but their abundance at the wind farm sites did not change. I conclude that data from EIAs and post-construction monitoring can be used to assess potential effects of wind farms on biodiversity and should be widely available for scientists and policy-makers, ideally via a central data repository. Second, I investigated whether noise from wind farms might affect birds as bird song could be potentially masked. It is widely known that anthropogenic noise such as traffic and urban noise affects communication in birds. To investigate whether birds are affected by wind turbine noise, I modelled how song from iii birds propagates in a hypothetical environment with and without wind turbine noise. I found that songs from species where most of the energy lies in the lower frequencies are masked by wind turbine noise. As this model can predict potential disturbance effects for specific species, it could be used as a tool during EIAs by identifying which species will be affected by wind turbine noise. Third, as bird communication is masked by wind turbine noise, male-male, male-female and parent-offspring communication could be affected. I investigated if male-male interaction in European robins (Erithacus rubecula) is affected by wind turbine noise. Males responded less aggressively during simulated territorial intrusion with background wind turbine noise. This could lead to reduced breeding success as males might not be able to effectively defend their respective territories. Finally, I explored whether bioaoustic recorders could be used as a replacement for human wildlife surveys. Using the European nightjar (Caprimulgus europaeus) as an example, I found that survey methods using bioacoustic recorders are much more accurate and cheaper than surveys by humans. This could aid EIAs as they require wildlife surveys to determine which species might be affected by the development.

Biochar, a product of thermochemical conversion of biomass, is a way to sequester carbon and mitigate climate change, improve soil agronomic properties and enhance crop production. However, such uses can only be valuable if the biochar does not negatively impact on normal soil microbially mediated processes that are important to soil health. The physical and biochemical characterization of biochar products is therefore important. One of the two central factors that affect the physicochemical properties of biochar is the production temperature (or highest temperature of treatment, HTT); the other being nature of the feedstock. A study of existing literature on biochar research reveals a lack of a systematic and rigorous approach focused on individual feedstock or HTT. It is to fill this gap that this study aimed to rigorously examine: the characteristics of biochar in a systematic way that focusses on a single feedstock source while varying the HTT from two different treatment facilities. It also aimed to assess the impact these biochars had on soil properties to which they (biochars) were added. The specific objectives were: to synthesize from the same feedstock six biochars, three from each of two different production processes (Batch and Continuous) over a range of pyrolysis temperatures and then subject the biochars to rigorous characterization; to investigate the influence of the synthesized biochars on a range of soil processes, and microbial diversities; to assess how the addition of the synthesized biochars to two soil types affects the physicochemical properties of the amended soil and influences plant growth. Sitka Spruce (Picea sitchensis) wood was pyrolysed at 400, 600 and 800oC. Experimental methods used included; titrimetric analyses, combined thermogravimetry – differential scanning calorimetry – quadrupole mass spectrometry, Fourier transform infrared spectroscopy and gas chromatography – mass spectrometry. In order to assess the impact of the biochars on the soil environments, a fully replicated and systematic plant growth trial was done. The post-harvest amended soils were then used to measure soil processes and also determine microbial community diversity against chosen controls. Results obtained from this study showed altered physicochemical properties of the biochars (increases in pH and total organic carbon; decreases in cation exchange capacity and water holding capacity), confirming the first hypothesis that biochemical and physical properties of the biochar are systematically altered with increasing HTT. However, there was very little difference between the properties of the biochars from the different production processes indicating that uniformity can likely be predicted based on HTT. Biochar addition to soil enhanced its basal respiration rate in the low pH soil but suppressed it in the near neutral soil, suppressed denitrification enzyme activity in the near neutral soil and these effects were to some extent affected by HTT. Biochar addition raised the total organic carbon content and lowered bulk density in both the acid and near- neutral soils and also increased the pH in the acid soil but not in the near neutral soil. The significant alteration of these soil properties was also influenced by changing the HTT. Biochar addition also influenced leek growth compared to the controls only in the acid soil. However, altering the biochar HTT had no significant effect on leek growth in both soils.

Trigeneration and the use of biofuels are two research topics which are important in trying to help relieve global energy shortage and bring about a reduction in greenhouse gas emissions. Trigeneration produces electricity, cooling, and heating simultaneously using a single fuel source and can operate at a high efficiency rate. The use of biofuel provides a renewable and carbon neutral substitution for fossil fuels. This research thesis describes the development of a biofuel micro-trigeneration (BMT) system using raw vegetable oils and explores the feasibility of meeting the total energy demand of a typical household. The system was designed and constructed using a 6.5kW single cylinder diesel generator as the prime mover, two heat exchangers for recovering waste heat from the engine coolant and exhaust gas, and an absorption refrigerator driven by exhaust gas heat. Four raw vegetable oils: sunflower, rapeseed, jatropha and croton oils were preheated to 90℃ and used in the study. The system performance using the vegetable oils was compared to that of the gas oil. Experiments were carried out to determine the fuel properties of the oils, including viscosity, density, higher heating value and fatty acid components. Power generation, combined heat & power and trigeneration tests were also carried out. The experimental results reveal that the BMT system performed with a high efficiency of 65% for trigeneration at full load, and CO2 emissions was reduced by around 60% compared to single power generation mode. The exergy efficiency was also increased by approximately 5 points. An engine model was developed using DIESEL-RK software to study the engine performance and emissions using different fuel types. Optimizations were performed to improve the engine performance and emissions. A trigeneration system model was also developed using Dymola software and was used to predict the dynamic performance of the system parameters. These models and simulation studies were validated against experimental results and matched well with the experimental results; hence can be used to explore wider system design and performance considerations. Both the experimental and theoretical studies have proved the feasibility of the BMT system to meet the overall energy demand of a household user.

This study addresses the global technical challenges of resource depletion and climate change by developing the first demonstration of incorporating smart energy storage (super-capacitors and batteries) with bio-fuel micro-tri-generation (BMT-HEES) for domestic applications. The developed system is capable of producing required heat, electricity and refrigeration from renewable bio-fuels for an average British household usage, and dynamically regulating the energy distribution within the system by using a novel energy storage system and a following electric load (FEL) energy management method. In this study, an extensive literature review has been carried out to investigate previous trigeneration and hybrid energy storage systems with a particular focus on their features, advantages and challenges which provide a basis for further improvements. The research work started with a preliminary investigation to fully understand the dynamic characteristics of lead acid batteries and super-capacitors used in combination to provide the desirable electrical output. The test results suggested that the super capacitors performed better than batteries in meeting transient electrical demands. In order to develop a complete BMT-HEES system, computational modeling and simulation was then conducted in the Dymola simulation environment, where the complete BMT-HEES system with advanced operational strategies has been implemented followed by case studies. System performance was assessed by evaluating key performance indicators including fuel consumption, dynamic response of each power sources, operational durations and energy efficiencies. A full experimental setup of the proposed system was also developed. Experimental tests on individual components and the BMT-HEES system as a whole have validated the effectiveness of the developed methodologies and techniques. Specific case studies have proved that the system can improve over the existing ones in terms of energy efficiency (with 47.86% improvement compared to one tri-generation system without HEES) and dynamic response for selected days as reported in the case studies. Test results from both simulation and physical experiments show that BMT-HEES can satisfy the fluctuating energy demands faithfully and instantly with high system efficiency for domestic applications. In addition, the predicted performance based on the developed methodologies has a good agreement with actual measurements. The low error of each assessment indicator provides iii the confidence that the system models can predict the system performance with good accuracy (all of the errors were within 3%). The developed technologies in this study can help cut down the carbon footprint in domestic environments, facilitate a shift towards an environment-friendly lifestyle, and in the long run, improve the quality of human life. Moreover, the established system is flexible, scalable and inter-connectable. That is, the system can incorporate other types of bio-fuels or other sources of new and renewable energy (wind, solar, geothermal, biomass etc.), depending on the availability of the energy and location of the system used. In addition to the small-scale domestic environment, the physical system can be scaled up to be used in larger commercial and industrial environments. It may be used as a stand-alone energy system or it can be interconnected with neighboring energy systems or connected with the power grid as a distributed generation set if there is a need (or a surplus) of generated electricity. Without doubt, this will require further work on this inter-disciplinary topic as well as new innovations in the fields of energy networks and smart grids.

Agricultural intensification is a major threat to a range of biodiversity. Of particular concern at a Europe-wide level are population declines of farmland birds, an index of whose numbers are taken to be an indicator of the health of biodiversity as a whole. In this thesis, I explore how to aid the populations of a declining farmland raptor, the Common Kestrel Falco tinnunculus, via the potential management of habitat, and then I link this to Agri-environment Scheme (AES) options, which require continual adaptive management to maximise their benefits. AESs have been responsible for the creation of additional areas of grassland in the British countryside, which could be expected to be of benefit to the Kestrel; a grassland hunter. A study of foraging breeding Kestrels showed that they select habitats non-randomly with cut grass being selected over all other available habitats. I then explored the potential effects of vegetation management on Kestrels’ preferred prey, small mammals, in a manipulative field experiment. While most small mammals will leave an area of grassland after mowing, I show that a small number may remain as long as some form of cover – such as the cut grass – remains in situ. I investigated the temporal effects on farmland bird species of cutting grass both within whole fields and on field margins, There was a rapid drop-off in use of grass fields after cutting suggesting a rapid decline in available resources. Field margins that were cut in strips were favoured by some species, although others preferred to use the longer, control, vegetation.Overall I conclude that targeted cutting of small patches or strips throughout the year would create mosaics of different habitat and therefore be of benefit to a range of different declining farmland biodiversity, and could be a worthwhile addition to AES field margin prescriptions.