Humic acid (HA) can effectively bind several hazardous metals. The interaction between HA and metal ions plays an important role in metal mobility and bioavailability in the environment. Abiotic humification processes can provide a potential and promising way to synthesize humic acids with better metal binding ability than their naturally occurring counterparts. The aim of the PhD project is to investigate the synthesis and application of synthetic humic-like acid (SHLA) for water/wastewater treatment and soil remediation. This thesis showed the log K and complexation efficiency of SHLA were higher at higher pH, lower ionic strength, higher temperature and higher SHLA concentration, and the effects of the above environmental factors on the complexation reaction are similar to natural HAs. Eleven SHLAs were prepared via a range of abiotic humification conditions. The results showed that SHLAs with a higher content of carboxylic groups, more aromatic structures and a higher degree of humification, would have a better Cu complexation ability. The optimal abiotic humification conditions to synthesize SHLA with better copper complexation ability were also determined. When applied as a soil washing agent, SHLA was more effective than some common washing agents, like Na2EDTA, citric acid, commercial HA and tartaric acid, and reduced the bioavailability and environmental/human health risk of metals. When applied as an adsorbent, the adsorption process between SHLA and Cu2+ was favourable, spontaneous and endothermic, and was described by the pseudo-second-order kinetic model, Langmuir and Freundlich models. The Cu2+ adsorption capacity of SHLA was much higher than many of the humic acid-based materials reported in the literature and the SHLA can be regenerated by HCl. Besides, SHLA was able to remove co-contaminant metals from solution. When applied as a soil amendment, SHLA lowered the bioavailability of Cu, Zn and Ni, but increased the bioavailability of As. Besides, the addition of SHLA could increase TOC and WSC of soil but decrease the soil pH. This thesis has shown that it is possible to synthesize SHLAs that show great promise for use in remediation of contaminated water sources and soils.

Corrosion of steel reinforcement is a major concern in concrete construction, particularly in aggressive environments. Therefore corrosion resistant materials such as fibre composites are becoming increasingly feasible as an alternative concrete reinforcement. There are relatively few reported design guidelines for fibre composites in concrete. Hence, there is an urgent need for research and development to extend existing guidelines and standards such as those produced by the UK Institution of Structural Engineers and the ACI Committee (US), to encourage the wider use and acceptance of fibre composites as an alternative to steel in reinforced concrete elements. This investigation compares the behaviour and properties of a range of reinforced concrete beams under two point loading comprising different concrete grades and types using both steel and Glass Fibre Reinforced Plastic (GFRP) as primary and secondary reinforcement. A variety of conventional and 'novel' rebar configurations were used to assess their effect upon material efficiency and load capacity. Compressive and tensile strength and elastic moduli of all component properties were measured together with load, deflection, rebar and concrete strains on the reinforced concrete beams. Health and safety concepts through a risk assessment process were introduced for the testing at an early stage of the investigation. Principal measures of beam performance include the ultimate load capacity, stiffness and failure modes together with a 'performance quotient'; a mathematical expression derived as an efficiency comparator for beams of different types and composition. Photographic and video records were also used to monitor behaviour throughout. Experimental measurements generally showed good agreement with the corresponding theoretical, quasi-theoretical and design based values although the latter tended to overestimate the structural performance of the beams. In general, load capacity increased with increase in main rebar area but was affected to a lesser extent by concrete strength. The beams reinforced with steel had a greater load capacity than those reinforced with GFRP. However, GFRP reinforced beams generally displayed a greater capacity to absorb energy than steel but exhibited reduced stiffness at any given load although this was enhanced by the inclusion of glass fibres in the mix. Cracks in the GFRP reinforced beams were usually larger and deeper compared with those in the equivalent steel reinforced beams. Failure of the more lightly reinforced steel beams, including one GFRP beam, were predominantly in 'flexure'. The more heavily reinforced steel and the remainder of the GFRP reinforced beams exhibited mostly 'shear-bond' type failure. The 'novel' rebar geometry proved to be a simple, efficient and viable alternative to conventional rebar configurations in terms of load capacity and preferred mode of failure. It is suggested that further developments and applications could focus on small reinforced concrete elements such as lintels in aggressive environments and further refinement of the 'performance quotient' concept.

An improvement to the standard of discharges from combined sewer overflows is necessary to meet the challenges set by the EC Urban Waste Water Treatment Directive (1991). To prevent aesthetic pollutants being discharged from a CSO, it is first necessary to gain an understanding of the quantity and temporal distribution of solids that enter the structure. This knowledge can then be used to predict the quantity of solids that are presented to a CSO under storm conditions. A field study was undertaken to determine the quantity and temporal distribution of solids entering a combined sewerage system and their transportation through the network in dry and wet weather. Flow monitoring and aesthetic pollutant sampling was undertaken in dry and wet weather at three catchments that contained different population types. The aesthetic pollutants sampled were characterised and tested in a laboratory to determine their settling rate. Analysis of the sampled data has indicated that aesthetic pollutants are stored in upstream sewers and private drainage connections during the dry weather period prior to a storm occurring. These pollutants and those within the flow in dry weather are transported out of the sewer at the start of the storm as part of a first foul flush. Sampling showed that over 80% of the solids by mass were faeces and toilet tissue, with a comparatively small number of sanitary products in the remaining percentage. Different solids are stored at different rates and this is clearly linked to the antecedent dry weather period and the quantity of solids that enter the system. The quantity of solids entering is also linked to the population type. A solid input and transportation model has been developed to predict the quantity of solids entering and moving through an upstream sewer system in dry and wet weather. The accuracy of the model is good particularly in the context of the variability of the solids that enter the system. The model predicts the quantity, rate and temporal distribution of six types of solids that could enter an upstream CSO and could aid in the development of more cost effective CSO solutions.

Maximising global food production is a priority for the international community. Ground-level ozone (O3) – a greenhouse gas and air pollutant – reduces yield in many important crops, and is a likely contributing factor to the global yield gap. This body of work applies experimental and modelling approaches to investigate how O3 reduces yield in soybean and wheat, and how these responses can be represented in models.

A multi-proxy approach analysing pollen, macro-charcoal, sediment characterisation and elemental profiles was used to develop palaeoecological records and reveal environmental changes since the late Pleistocene- Holocene transition period from Mau Forest and since the mid-Holocene from Amboseli. Mau Forest was characterised by diverse Afromontane forest taxa between �16,000 cal yr BP and �13,000 cal yr BP which decreased during the Younger Dryas. During the early Holocene, there was a slight increase in montane tree taxa and the main vegetation change noted during the Holocene was the increase in woody shrubs and herbs. The pollen, sediment characterisation and elemental profiles revealed that climatic variability was the main driver of forest composition change and periods of aridity and wetness were identified at�15,000, �13,400, �12,000 and �1200 cal yr BP where there was increased organic matter, sand, magnetic susceptibility with peaks in detrital elements suggesting periods of wetness. Four new Amboseli records dating from the mid Holocene (�5000 cal yr BP) revealed a predominantly dry environment characterised by localised wet and dry phases and fire activity. The spatial differences observed from the Amboseli records are attributed to hydrological variance as the swamps are all fed by ground water and the differential use by humans and wildlife. Kimana, Enkongu and Esambu swamps are Cyperaceae dominated; the pollen records indicate that Amboseli is a grassland savannah dominated by Poaceae, Acacia, Commiphora and Euphorbia. The pollen composition and abundance and charcoal concentration levels vary between the four Amboseli sites indicating localised drivers and controls of fire at each site. This long-term information is useful in the development of ecosystem management policies which are constantly being updated due to the evolving pressures caused by increasing populations and changing land use around the two ecosystems.

With a growing global population projected to surpass 9 billion by 2050, and associated food demand anticipated to increase by 70 to 100%, food security has emerged as a land-use challenge of critical importance. This has raised concerns regarding how increased agricultural production can be achieved without compromising the natural environment. This challenge of balancing agricultural and environmental land-uses occurs at a range of scales addressed by this research, beginning with high level policies and working down towards farmers, the actors ultimately responsible for the management of arable land. The study was comprised of three interconnected research projects completed in two regions of comparison: Ontario, Canada and England, United Kingdom. First, I compared the agri-environmental land-use policy context of both cases through a thematic analysis of policy documentation. Second, I completed 24 interviews with representatives of agricultural and environmental stakeholder organisations to examine the agri-environmental land-use preferences of these actors. Third, I conducted 30 interviews with farmers to investigate their views and motivations relating to the adoption of pro-environmental activities. In addition, due to the timing of the research, an unanticipated opportunity arose to explore the views of stakeholder organisations and farmers in England on post-Brexit agri-environmental policy. Overall, my main finding was that England and Ontario have taken very different approaches to managing competition between agricultural and environmental land-uses with Ontario leaning towards land-sparing and England toward land-sharing. I found that this may be partially explained by different stakeholder preferences for agri-environmental land allocation and the attachment of actors to different agricultural paradigms (productivism / post-productivism). Importantly, the use of an original multi-level comparison of agri-environmental land-use in England and Ontario illuminated many similarities and differences that would not have been apparent in the analysis of a single case. As a result, the thesis offers multiple contributions to knowledge for rural, land-use, and comparative studies.

This thesis aims to evaluate the role of overseas development assistance in the delivery of water and sanitation related MDGS from a systems perspective, in order to deliver a more coherent framework that seeks to reduce developing countries’ water and sanitation needs. To achieve this, an assessment of the delivery of water and sanitation related MDGs is conducted and the main causes of concern are identified. From these, funding was isolated for further exploration, as it underpins and influences the other issues. The role and extent to which funding drives the delay in the completion of the water and sanitation MDGs is investigated on a regional level from a systems perspective, looking at the funding mechanisms as a whole. A set of hypotheses accounting for the hindrance of the MDG is determined. To test said hypothesis, the part and degree to which funding mechanisms drive the delay in completing the water and sanitation MDG on a national scale is explored using the countries in Sub-Saharan Africa as a case study. The evaluation pinpoints a series of findings recognized as root causes for the lag in the achievement of the water and sanitation MDG. Once the root causes and main areas of concern are identified and the current system is understood, a solution that answers the issues is proposed and a coherent framework that aims to reduce developing countries’ water and sanitation needs is developed. Based on better funding practices, a Needs Based Approach is recognized as a resolution that addresses all the problems.

In Europe the regulations that limit vehicle emissions, the Euro Standards, have failed to effectively tackle pollutant emissions in the real world. This thesis contains an appraisal of the real world emissions of modern European vehicles, which were identified as a major cause of uncertainty in UK policy with respect to compliance with air pollution legislation. The thesis includes key background information on air pollution and its control in the UK and a comprehensive review of the existing literature relating to real world emissions of petrol and diesel passenger cars. The real world emissions performance of modern vehicles was assessed using Portable Emissions Measurement System (PEMS) data, provided by Emissions Analytics, which included 147 Euro 5 and 6 diesel and petrol vehicles. Comparisons were made to the emissions factors of the recommended air quality transport model of the European Union, COPERT, as well as the Euro standard type approval limits. The potential impact of these real world emissions was also assessed using the UK Integrated Assessment Model to perform scenario analysis up to 2030. Scenarios were used to explore the potential effect of different passenger car emissions factors on total UK NOx (nitrogen oxides) and CO2 (carbon dioxide) emissions, damage costs and annual mean concentrations of nitrogen dioxide (NO2). Considering the results of these investigations, wider conclusions were drawn as to how policy makers might effectively reduce passenger car related pollution in European towns and cities. A key conclusion of this thesis is that due to the large variability in the real world emissions of vehicles within a single Euro class, policies could be more effect if real world variability was taken into account, as opposed to relying solely on the Euro standard.

This dissertation explores the field of electricity systems modelling and optimisation. We develop new tools, techniques, and concepts to advance systems and technology analysis. Based on a process systems engineering approach, we apply mixed-integer linear programming (MILP) to develop least-cost optimisation models of a national-scale power system in different temporal and complexity variations. The Electricity Systems Optimisation models integrate detailed power plant operation and long-term systems planning to overcome limitations of existing models for technology and system design. We present implementation strategies to include endogenous technology learning and myopic versus perfect foresight planning considering disruptive events. This is enabled through data processing and MILP reformulation techniques developed and applied in this work. We further introduce a new technology valuation metric, the System Value (SV), which quantifies the reduction in total system cost caused upon the deployment of a power generation or storage technology. Unlike purely cost-based metrics, the SV enables a fair comparison of different power technologies taking the whole-system impacts of deployment into account. We find that the SV of a given technology is a function of its penetration level and initial configuration of the system. In a future United Kingdom setting, grid-level energy storage provides the greatest value under a premise of decarbonisation and maintaining security of supply. Additionally, dispatchable and flexible low-carbon power generation, such as Carbon Capture and Storage equipped power plants prove particularly valuable in being able to accommodate higher levels of intermittent renewable power generation and providing ancillary services. On a systems level, we find that including endogenous technology learning in power systems planning emphasises the economic advantage of early investments in low-carbon technology. Myopic power systems planning can lead to sub-optimal capacity expansion. Even under the possibility of breakthrough technologies becoming available before mid-century, deploying existing low-carbon technologies early on proves advantageous from an economic and climate perspective.

Over recent decades, conservation projects, such as Protected Areas (PAs) and Payment for Environmental Services (PES), have increasingly incorporated poverty alleviation goals or targets towards improving human well-being in addition to biodiversity conservation outcomes. While methods to evaluate biodiversity are widely available, there is less guidance on how to measure the impacts of conservation interventions on human lives. Economic proxies have been popular, yet rarely reflect the multi-faceted incentives of resource users and their responses to conservation interventions. In this study, I use mixed methods to investigate the effects of conservation interventions on human well-being in Northern Cambodia, using three complementary approaches at different geographical scales. The Northern Plains landscape provides an ideal context for this exercise, because it includes two PAs and three PES initiatives, while also facing increasing development pressures in the form of large-scale agro-industrial development interventions: Economic Land Concessions (ELCs). I begin by exploring correlates of the spatial placement of ELCs, their outcomes in terms of deforestation rates, and the extent to which these development interventions trade off against conservation goals. The evidence indicates that ELCs not only fail to achieve their intended outcome but are also the main predictor of deforestation in the region, compromising environmental sustainability in the long-run. I then build on an existing longitudinal dataset from the Northern Plains to provide a medium-term evaluation of the impacts of PAs and PES on the socio-economic status of households in villages within PAs, compared with matched villages outside PAs. I demonstrate that external factors remain the main contributors to the socio-economic status of households across the landscape, with combined PAs and PES slightly reducing the rate of increase in household economic status and agricultural productivity, yet without impeding household development. The second half of this PhD offers a qualitative exploration of the conceptualisations of human well-being in the study area, to capture the multidimensionality and heterogeneity of well-being in the landscape. I find that individual well-being as well as village solidarity and trust are heavily linked with issues relating to land and resources, and their governance. From this study I developed locally relevant indicators pertaining to perceptions of salient land issues, which allow a more accurate assessment of the subjective dimension of human well-being across a landscape that features competing land uses from PAs and ELCs. The research findings highlight the complexity of attributing conservation impacts and capturing the direct and indirect consequences of conservation and development policies, and demonstrate how a more nuanced evaluation of conservation impacts on humans can guide future conservation interventions.