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Qatar is a desert where precipitation is uncommon and occurs mostly in winter. Qatar depends on desalination for drinking water and groundwater and recycled water for irrigation. There is overextraction of groundwater causing seawater intrusion. Re-use of treated wastewater (TWW) is extremely limited with only 14% of TWW being used for irrigation. This has led to the country disposing of unwanted water from various sources in artificial lagoons situated across the country where it evaporates and infiltrates the groundwater raising concerns over the possibility of environmental pollution. This is a unique situation that is limited to extremely arid countries. Research on the artificial lagoons is limited, with a noticeable knowledge gap in understanding the lagoon influence on Qatari aquifers. Accordingly, the hypothesis underpinning this research is that the quality and quantity of water in lagoons is currently having an impact on the groundwater reservoirs in Qatar. To validate this hypothesis a social survey, a hydrogeochemical survey and a microbial survey have been undertaken to establish the current situation and provide policy makers with recommendations for future lagoon management. A social survey was conducted through the distribution of online questionnaires to the public and conducting semi-structured interviews with policymakers responsible for water management in Qatar. The public had variable knowledge about the lagoons and expressed a willingness to learn more about them. Public and policymakers in Qatar agreed that there were both good and harmful consequences of the lagoons on groundwater and the environment. Policymakers' views differed, dividing into groups perceiving the lagoons as having the potential to degrade groundwater quality and those suggesting that infiltration of lagoon water would improve groundwater sources. Public opinion is important in lagoon management, thus policymakers agreed to raise awareness and incorporate public views with respect to water management in Qatar. Both public and policymakers encouraged the reuse of TWW and lagoon water and Qatar might leverage this approval to promote and extend its TWW reuse programs. A hydrogeochemical survey was conducted by sampling lagoons (n = 14) and wells (n = 54) in both the summer and winter of 2018 - 2019 (designated 'summer' & 'winter'). Water, soil and plants samples from sites irrigated with well water were analysed for multiple elements by ICP-MS. Major anions were determined by ion chromatography and organic and inorganic carbon was also measured. Lagoons violated the Qatari TWW reuse standards in terms of pH, TDS, TN, SO4 2- , Mn, and Zn. Groundwater samples violated WHO and Qatar drinking and irrigation standards in terms of pH, TDS, TOC, B, Ca, Cl- , Mg, Na, SO4 2- , As, Fe, Se, Sr, Tl, and U. Spatial and temporal variation in lagoons and groundwater salinization and water/rock process were visualised to illustrate the influence of lagoon water infiltration on adjacent aquifers. Soils (collected from close to lagoons and on farms) had Ni concentrations that violated EU and FAO/Who standards. Plant samples violated EU and FAO/WHO fodder standards in terms of Cr, Cu, Mn, Mo, Ni, Pb, Se and Zn. The multivariate statistical analysis revealed similar trends in the chemical variables of soils and plants from both farms and lagoons. Contamination from water and the environment tend to be higher in plants than in soil. A microbial survey was conducted using MALDI-TOF-MS to identify species of isolated bacteria strains (MacConkey and EMB selective media) collected from lagoons (n = 9) and wells (n = 13). Both groundwaters and lagoons were found to contain levels of coliform bacteria that exceeded national and international standards. Coliform bacteria in groundwater wells were observed to be associated with nearby lagoons, implying microbial infiltration. While the majority of the literature uses E.coli as a faecal indicator for wastewater contamination of groundwater, this research determined that P.aeruginosa is a more appropriate indicator in the Qatar lagoon context. In conclusion, this study examined three distinct scientific domains pertaining to the lagoon situation in Qatar: social, chemical, and microbial, with the goal that policymakers and managers in Qatar may benefit from the findings. Additionally, this research will serve as a baseline for future research and policy development for future lagoon management decisions in Qatar.

Mineral micronutrient deficiencies (MND), prevalent in Ethiopia and Malawi among most countries in sub-Saharan Africa, are linked to soil type. Dietary mineral intake is influenced by mineral content of edible portions of crops, and there is strong evidence that cereals grown in these regions have low uptake of micronutrients. The low nutrient uptake is attributed to soil conditions. Spatial information on soil and crop properties is therefore required to improve local estimates of MND risk in order to implement targeted and efficient interventions. Obtaining spatial information on soil micronutrients status and other relevant properties that affect their uptake requires substantial effort, and there are uncertainties in the resulting information, which depend, in part on the methods used for prediction and the sampling design. Therefore, it is necessary to use robust and efficient methods for spatial prediction which characterise the uncertainty of the predictions reliably. Furthermore, it is necessary that these uncertainties can be communicated effectively to stakeholder groups so that they can account for them at all stages from commissioning the survey through to making decisions based on the information. In this study, it was important first to understand how uncertain spatial information can be communicated to stakeholders (e.g., those in public health or nutrition and agronomy or soil science) through a systematic evaluation in the forms of maps. Evaluation of the test methods were done through a structured elicitation of the opinions of members of a stakeholder group about the usefulness of the methods. Stakeholders found that general measures of uncertainty, such as prediction error variances (e.g., kriging variance) were less clear than measures which integrated the uncertainty explicitly with the decision-e.g., the probability that the true value of a variable at a site if interest falls below a critical threshold. There was no evidence that they found verbal phrases these (e.g., "very uncertain") clearer than numerical values (i.e., a probability in the interval [0,1]). Following on this finding, it was necessary to examine how stakeholders interpret such probability information in more detail. Specifically, is it possible to estimate a probability threshold which a stakeholder group would choose to intervene, reflecting their assessment of the costs attached to errors of commission and omission? Further does this probability depend on framing of the problem (e.g., probability that a threshold is exceeded or that it is not exceeded) and does it depend on professional background of the stakeholder? In a designed experiment, stakeholders were presented with uncertain information on micronutrient supply from a crop, with the uncertainty expressed as a probability with positive framing (probability of adequate supply) or negative framing (probability of insufficient supply). The results showed that probabilities presented in a negative framing led to more conservative decisions, i.e., deciding to intervene at a much smaller probability of deficiency than if the equivalent probability of sufficiency were presented. The elicited probability threshold is prone to framing effects (i.e., how the question is posed), and that this effect interacts with professional group. The two components of this thesis described above showed how uncertain information can be effectively communicated to stakeholders to support decisions. The next task was to develop a framework for the planning, execution, and evaluation of surveys to address specific requirements of these stakeholders. This was based on a decision-theory approach to analyse the particular task, to identify the key uncertainties and their implications and so to enable stakeholders to ensure that an approach to survey would meet their needs. A particular task, based on research practices within the GeoNutrition project (Bill & Melinda Gates funded) was identified -the selection of the study sites to evaluate agronomic biofortification strategies for MND at selected sites based on soil soluble Se. The information required were analysed, and then the outputs of spatial prediction at national-scale of soil soluble Se by ordinary kriging, indicator kriging, linear mixed models and random forest were evaluated. There were substantial uncertainties by all three methods, and challenges with dealing with a complex statistical distribution. This work showed the importance of validation-internal and independent for understanding the suitability of spatial prediction to support decision making. Uncertainty should be considered when planning sampling for a geostatistical survey. It is important to consider how stakeholders can assess the implications of uncertainty in spatial predictions to determine appropriate sampling grid space for a geostatistical survey. Four approaches (offset correlation, prediction intervals, conditional probabilities and implicit loss functions), that can be used to assess the implications of uncertainty in spatial predictions using prior information on variability of the target properties, were presented to a diverse group of stakeholders in order to determine an appropriate grid spacing. There were variations in the selection made by each method. Some were not well understood. The one which stakeholder favoured, offset correlation, is not directly linked to decision making. More work is needed to develop sound but accessible ways to engage stakeholders with uncertainty consistent across planning and interpretation. Findings from this research will help in better understanding of uncertainties in the data obtained in the GeoNutrition projects thereby facilitating improved use and uptake of that information by decision makers in Ethiopia and Malawi. Better decisions will be made on sampling for such surveys in other countries which decide to undertake those using better methodologies for national-scale surveys of soil properties or similar environmental variables.

Past lacustrine and wetland sediments from arid regions, sensitive to changes in precipitation and evaporation, are important archives of past environmental variability. This thesis presents new data that contribute to the Quaternary records of Jordan through multi-proxy analyses of sediment archives from two study sites in southern Jordan; the Gharandal Valley and the Dead Sea Basin. Through detailed analyses of the sediments from the two study sites, the depositional environments, environmental conditions, and how these changed, and to some extent their timing were reconstructed. Sediments from the Gharandal Valley were investigated and collected from five different sedimentary sections (> 30 m sediments) and analyzed for particle size distribution, organic and carbonate content (through LOI), and elemental (through XRF) and minerogenic (through magnetic susceptibility) composition. The results indicated complex tectonic/climate-driven depositional environments prevailed in the valley, during Marine Isotope Stage (MIS) 6, alternating from fluvial in-wash to fluvio-aeolian and wetland deposition following the proposed valley outlet damming. The GH1 and GH2, the main sections in the valley, record the environmental aggradation from stream-fed wetland depositional conditions where thin wetland beds developed following in-wash events, in the lower parts, into more consistent wetland (wetter) conditions towards the top of the sections. These cycles were identified in 16 fining upward primary associations in the GH1 section and 8 fining upward primary associations in the GH2 section. The age estimate (MIS6) is consistent with wet phases recorded elsewhere in the Levant and increased monsoon precipitation recorded in southern Arabia suggesting that an influence of the two systems (the northeastern Mediterranean Cyclones and the southern tropical monsoon), which do not reach the valley site today, may have contributed to maintaining the wetland conditions in the valley during glacial stadials and interstadials. From the eastern side of the Dead Sea Basin (DSB), the lacustrine section DS1 was investigated. The section is primarily comprised of laminated pale and dark laminae and laminated detrital laminae with a thick gypsum-dominated bed. Considering the different nature of the sediments, the DS1 bulk sediments were first analysed using proxies mentioned earlier for the Gharandal Valley. In addition, the pale laminae were analysed for the carbonate isotope composition (δ13C and δ18O), mineralogy (through XRD) and carbonate crystal habit (through SEM EDS) analysis. Through preliminary U/Th dating of aragonite laminae, the DS1 section age was estimated at ca. 40 ka to 37 ka (MIS3). This places the section as part of the Lake Lisan Middle Member (ca. 58 ka to 31ka). Based on the sediment's lithology and the multi-proxy records, the environmental history of the DS1 section, of enhanced/reduced freshwater input into the lake (P/E ratio) at millennial, centennial and close to annual scales, is recorded in four distinct lithostratigraphic units. The units record relatively high lake levels, then lake level lowering and the deposition of the gypsum bed, a lake re-filling stage and return to stable relatively high lake levels. The environmental proxies suggest that during Greenland Interstadials (GIs), the lake level was relatively higher than during Stadials (GSs). The gypsum bed, the lowest relative lake level in the record, probably coincides with Heinrich Event 4. At centennial scales, the environmental proxies apparently record lake level changes corresponding to the GIs indicating variable amounts of freshwater reaching the DSB. An initial assessment of the moisture source was done based on the aragonite initial 234U/238U ratios variability and indicated the dominance of the Eastern Mediterranean cyclones in driving the deposition of the DS1 section. The results of this thesis emphasize southern Jordan's sedimentological and palaeoclimatic heterogeneity and the complexity of the past environmental records that can be recovered. This indicates the need for continued investigations and particularly more dating control, based on more comprehensive and detailed approaches in order to achieve a better assessment of the Quaternary sedimentological and environmental variability in the region.

The monitoring of land motion can provide critical information on potential geological hazards. Geohazards are phenomena that can pose significant socio-economic and environmental risks. There have been an increasing number of geohazard mapping programmes across the world that utilise space-related technologies, such as the Global Navigation Satellite System (GNSS) and Earth Observation (EO). Differential interferometric synthetic aperture radar (DInSAR) is an EO technique that utilizes spacebourne synthetic aperture radar (SAR) data to measure millimetric rates of ground deformation from the differences in phase between image acquisitions. However, two significant limitations of DInSAR analysis are that incoherence restricts measurements to urbanised or rocky areas and free, readily available data with sufficient temporal coverage has not historically been available. In this regard, the Intermittent Small Baseline Subset (ISBAS) is a processing algorithm which is capable of computing velocities over land cover types that have typically been unfavourable for DInSAR analysis. In addition, as part of the Copernicus EO program, the Sentinel-1 satellite provides readily available conflict-free data every 6 days in Europe. The purpose of this research is to demonstrate the potential of the ISBAS processing method and Sentinel-1 SAR data for enhanced capability to monitor ground movements related to geological hazards. Previously, the initial results utilizing the ISBAS method on archive data have identified notable deformations over former coalfields in the UK. Here, previous research was revisited over the Northumberland and Durham coalfield, whereby the ISBAS method was applied to archive and Sentinel-1 data providing deformation data spanning 3 decades. The results show that unexpected and changing amounts of ground motion can be present over former coalfields. The near complete coverage of measurements aided the interpretation and most notably temporal correlations between the rise of mine water and surface heave were made. The results showed that ISBAS measurements had the potential to be utilized to map changes in groundwater levels. Subsequently, an analytical model based upon the principle of effective stress and concept of mine water ponds was developed to relate changes in groundwater levels to changes in the thickness of the strata and, hence, determine surface movement. The forward models estimate surface heave utilising measurements from monitoring boreholes. The models were calibrated and validated using ISBAS measurements, where good agreement was found between the model and the DInSAR, over the demonstration site of the Nottinghamshire coalfields. The ISBAS measurements were then inverted to estimate the change in groundwater levels across the whole coalfield, providing greater spatial coverage than could be inferred from the spatially sparse monitoring boreholes or the forward model. The inverse map was then utilized to predict the time it will take for groundwater to discharge out of the Coal Measures rock. Additionally, the seamless coverage and regular revisit of Sentinel-1 affords the potential for wide-area monitoring of mining deformations and other geohazards. This was demonstrated over the Netherlands where multiple stacks of data were processed and mosaicked together to produce a wide-area-map. The motions, attributed to compressible soils, infrastructure settlement, peat oxidation, gas production, salt mining and underground and opencast mining, were validated with all available independent ancillary information such as previous persistent scatterer interferometry (PSI) deformation maps, models of subsidence and settlement susceptibility and GPS measurements. A statistical analysis showed that measurements in rural areas can provide reliable information with a high degree of confidence (5σ). Finally, the processing requirements for a full Europe-wide deformation map were calculated to determine the opportunity and challenges Sentinel-1 presents for future operational services.

In the Philippines, aquaculture in freshwater lakes contributes significantly to its economy, food security and employment. However, intensive aquaculture often leads to degradation in lake ecosystem integrity because of nutrient fertilisation resulting in harmful algal blooms (HABs), eutrophication and degradation of water quality. The few limnological and palaeolimnological studies carried out on Philippine lakes demonstrate a link between aquaculture activity and degraded water quality but there is a lack of information to help define how lakes have reacted over time to changing intensities of aquaculture and other catchment effects. This research attempts to redress this imbalance by using two different palaeolimnological approaches to assess the impact of aquaculture on six of the Seven Lakes of San Pablo (Luzon Island). Both approaches used multiple proxies, specifically, chlorophyll and carotenoid pigments, carbon and nitrogen isotopes (δ13C, δ15N) and C/N ratios to help disentangle lake-specific effects of aquaculture from the impacts of regional drivers. The first approach used generalised additive models (GAMs) to assess responses of lakes along an aquaculture disturbance gradient and hence whether lake response was proportional to the level of aquaculture. The second approach endeavoured to quantify the extent to which aquaculture (and other drivers) led to change in algal communities using variance partitioning analysis. Using this whole-ecosystem "experimental design" across individual lakes allowed for a more critical interpretation of the pigment and isotopic records. Both approaches concluded that there was no proportional relationship between changes in the proxy record and level of aquaculture disturbance, suggesting aquaculture is not the main driver of change. Land use changes (since 1950) explained the greatest proportion of variance and corresponded to periods of significant temporal change indicating it was a more dominant driver of change in algal communities. As aquaculture intensity increased, lakes became more eutrophic and anoxia increased due to nutrient enrichment from a combination of anthropogenic (urbanisation, coconut plantations and aquaculture) and climatic factors. In the majority of the lakes, changes in the proxy records predate the introduction of aquaculture, providing evidence that aquaculture exacerbated pre-existing change especially in the lakes with the highest aquaculture disturbance. Furthermore, each lake had a distinctive response to aquaculture due to the impact of multiple stressors (climate, land use and aquaculture) especially on the high disturbance lakes, and the modification by individual lake characteristics such as hydro-morphology. Mitigation strategies, therefore, need to be specifically developed for each lake, with consideration given to their distinct morphological features and how this influences their complex response to aquaculture and other environmental pressures.

Satellite data have fundamentally changed how we perceive and understand the world we live in. The amount of data produced is rapidly increasing and classical computing resources and processing tools are no longer sufficient. These massive amounts of data require huge storage in addition to advanced computing capacity in order to allow users to benefit from the derived datasets. Cloud computing has provided the required storage and computing capacity on a scalable level to add or remove resources according to requirements. Simultaneously, recent advances in data processing techniques such as Deep Learning (DL) have paved the way to integrated solutions for Earth Observation (EO) big data understanding. By bringing together a unique combination of computing capacity, ultra fast data storage and advanced data processing techniques, our ability to derive useful insights will be revolutionised. This thesis focuses on harnessing cloud computing and deep learning capabilities to enhance spatial resolution of satellite imagery data. Particularly, the thesis highlights cloud computing architectures to accommodate satellite image processing services. A conceptual data model was developed to enable utilising cloud computing resources with EO big data in near real-time. Moreover, a state-of-the-art super resolution algorithm (SRCNN) was adapted and tested in detail to be exploited with the satellite image domain. In addition, a novel fusion-based data augmentation approach was developed to boost super resolution accuracy. To evaluate the super resolution accuracy with a real-life application, landcover classification was adopted to assess the accuracy between super resolved Landsat-8 data and crowd-source data collected using the Google Earth interface. The accuracy achieved opens a wide field of research with deep learning and data augmentation in the satellite image super resolution domain.

A palaeolimnological study of three lakes on Disko Island, West Greenland was conducted across a hydrogeomorphic landscape gradient, to reconstruct principally changes in algal pigments, lipid biomarkers and carbon isotopes (δ13C) to investigate carbon cycling at multiple scales and resolutions. All three records reconstructed recent change on Disko, with records from lake Disko 2 additionally spanning since ~7640 cal. yr BP and lake Disko 4 since ~1260 cal. yr BP. Changes in sedimentary proxies were broadly consistent with the spatially and temporally heterogeneous environmental change known to have occurred across the Arctic over these periods, including recent warming (RW), the Little Ice Age (LIA) and the Medieval Climate Anomaly (MCA). However, the individual lake responses to these changes were highly landscape specific. Changes in algal pigments were linked to variations in the inputs of nutrients and DOC from soil microbial activity, variations in permafrost melt regime and glacier melt. Evidence of disturbance from catchment freeze-thaw processes, glacier inputs and the effects of permafrost melt on algal communities varied between lakes. At the highest position in the landscape gradient, lake Disko 2 had poorly developed soils and lower glacier coverage, with simple algal communities, but pigment and δ13CTOC changes since ~7640 cal. yr BP reflected individualistic responses to overarching drivers, consistent with the current understanding of heterogeneous pan-Arctic environmental change. Replicate cores with proximity to talus and debris flow had differing signatures, highlighting the role of geomorphology. In lake Disko 2 there was some similarity between Greenland Ice Sheet surface area and pigment biomarkers of cryptophytes (alloxanthin), which suggests if locally similar, catchment ice variation may regulate nutrient and DOC release from catchments, stimulating algae. At a mid-elevation position in the catchment, lake Disko 1 meltwater inputs from an upstream retreating glacier (since the end of the LIA) may be stimulating algae through increased nutrients and DOC supply, although soil nutrient cycling and permafrost release present in the catchment U-shaped valley may also be contributing to these increases. At the lowest position in the landscape, lake Disko 4 has a complex and variable pigment response likely influenced by multiple glacier inputs, thicker permafrost, greater vegetation and more developed wetland areas, together regulating the cycling of nutrients and DOC. Higher maximum pigment concentration during the MCA, compared with the LIA reflect the spatially and temporally heterogeneous expression of these events across the Arctic. Despite individuality in catchment filtering, all three lakes on Disko Island were found to have recent increases in algal production, which when combined with recent increases in carbon burial suggests these lakes are becoming increased carbon sinks. Although this increased carbon burial reflects a minor store in lakes compared with release to downstream waterbodies, if upscaled across the Arctic this change could be globally significant and should be integrated in future models. With future warming, catchment processes are likely to play a pronounced role in mediating algal community structure in lakes across the Arctic.

The type of feedstock and host rock utilised in ex situ and in situ Carbon Capture and Storage by Mineralisation (CCSM) is an important aspect of these technologies, and detailed appraisal of candidate mineral/rock performance in the presence of CO2 may greatly improve CCSM efficiency. Here, a detailed mineralogical and geochemical investigation of serpentine minerals and ultramafic rocks under laboratory-controlled experiments simulating ex situ and in situ process conditions is presented. Feedstock serpentine minerals were analysed comprehensively, prior to experimental processing. The identification of antigorite was unequivocal using a combination of X-ray diffraction, Fourier Transform Infrared Spectroscopy and/or Thermo-gravimetric Analysis. However, the analysis of chrysotile and lizardite proved to be more challenging, especially when the two polymorphs were finely inter-grown. This study highlighted the structural, textural and chemical complexity of serpentines and showed that great care must be taken when analysing this mineral group for CCSM. Investigation of the acid leaching of serpentine minerals under conditions of 70°C and 1.4M NH4HSO4 provided fundamental insights into the rate and extraction efficiency (EE) of Mg2+ and associated controlling factors, under conditions relevant for ex situ CCSM. It is demonstrated that EE is a function of mineral reactivity and depend on a complex interplay between crystal structure and chemistry. Generally, poorly crystalline and highly disordered phases with low levels of Al3+ were found to be suitable feedstock materials for acid digestion pre-treatment. Chrysotile, lizardite 2H1 and poorly crystalline serpentines showed up to 85% Mg2+ EE after 3 h of acid leaching, and hence are recommended as best feedstock materials for CCSM, whilst antigorite and Al3+-rich serpentines proved to be largely unsuitable, showing low levels of EE of ~ 20%. Examination of dunite, harzburgite and serpentinite under conditions relevant for in situ CCSM, i.e. 70°C and 100 bar CO2 pressure, provided insights into rock reactivity as a function of composition and texture, and the progression of in situ mineral carbonation. The rate of net Mg release and thus the extent of subsequent carbonation were greatest for serpentinite, providing ca. 3% carbonation after six months. However, mineral reactivity within serpentinite was preferential, i.e. significantly enhanced within secondary vein serpentine, being thus, the main source of Mg2+ for magnesite precipitation. Reaction-induced transformation and hence mineral carbonation of dunite and harzburgite were less pronounced over the same time-scale. The reaction of serpentinite with wet supercritical CO2, as opposed to CO2-saturated brine, significantly affected rock integrity, with the exposure of more surface area and promotion of fluid-rock interaction. In particular, it is shown that ferric iron oxidation and the precipitation of goethite impacts upon surface mineral dissolution at exposed surfaces, thereby hindering subsequent carbonation. Overall, this study highlighted the importance of host rock choice for in situ CCSM and the need for detailed petrographical and geochemical investigation of any proposed CCSM repository prior to technological process modelling.

Environmental histories are multi-dimensional accounts of human interaction with the environment over time. They observe how and when the environment changes (material environmental histories), and the effects of human activities upon the environment (political environmental histories). Environmental histories also consider the thoughts and feelings that humans have had towards the environment (cultural/ intellectual environmental histories). Using the methodological framework of environmental history this research, located in sub-tropical northern Belize, brings together palaeoecological records (pollen and charcoal) with archival documentary sources. This has created an interdisciplinary account which considers how the vegetation of northern Belize has changed over the last 3,500 years and, in particular, how forest resources have been used during the British Colonial period (c. AD 1800 – 1950). The palaeoecological records are derived from lake sediment cores extracted from the New River Lagoon, adjacent to the archaeological site of Lamanai. For over 3,000 years Lamanai was a Maya settlement, and then, more recently, the site of two 16th century Spanish churches and a 19th century British sugar mill. The British archival records emanate from a wide variety of sources including: 19th century import and export records, 19th century missionary letters and 19th and 20th century meteorological records and newspaper articles. The integration of these two types of record has established a temporal range of 1500 BC to the present. The palaeoecological proxies provide a low resolution record over a period of 3,500 years (c. 1500 BC – AD 2010) whereas the archival record provides annual resolution over a period of approximately 150 years (c. AD 1800 – 1950). This research also uses documentary sources to reconstruct temperature and precipitation for Belize City during the period 1865 – 2010, which is the first of its kind from Belize, and the oldest continuous record from Central America. It also provides the meteorological context for further exploration into British colonial interaction with ‘tropical’ climates. Perhaps because of its status as Britain’s only Central American colonial outpost, Belize has remained on the periphery of research concerning European interactions with tropical climates. This environmental history draws together a new account of health, place and space in the 19th century colonial tropics, drawing out how different understandings of the aetiologies and transmission of disease developed, in particular yellow fever. These different research strands are brought together to create an account that considers material, political and cultural aspects of environmental history. This has enabled the identification of eight phases of human interaction with the landscape at Lamanai, which are broadly indicative of general trends across northern Belize. These include the establishment of Maya field-based agriculture c. 1600 BC and a later phase of substantial Maya construction and site development c. 170 BC – AD 150. A period of active Maya management of forest, field, savanna and palm resources is also observed c. AD 500 – 1000. Polarised imaginings of the Maya as both destroyers and protectors of the tropical forest are challenged. Spanish interaction with the landscape is evident during c. AD 1500 – 1700 and this is followed by a period of substantial British colonial exploitation of timber resources, with logwood extracted c. AD 1660 – 1910 and mahogany extracted c. AD 1750 – 1945. These periods of extraction were only identifiable in the pollen record by combing the chronology from the documentary record with observed changes in the vegetation record and this demonstrates how these two contrasting methodologies can be usefully integrated. This environmental history rejects the binary opposition of benign, passive Maya landscapes and the violent, devastated European colonial landscape (Denevan, 1992). Analysis of the pollen and documentary records reveal that biodiversity is at the highest levels post AD 1950, which suggests that the forest can regrow even after multiple, diverse and prolonged periods of anthropogenic use in a matter of decades.

Of numerous aeolian studies around the world, few have been dedicated to dust trapping in the Saharan regions and none is known in Libya. This research aims to explore the extent of dust activities in the western part of Libya, the main factors that influence dust entrainment and deposition, the likely regional emission sources transporting aerosol to this part of the country and ultimately to establish base line information in space and time based on a study area larger than the size of the UK. Dust trapping was carried out at thirty sites on a monthly basis starting from the beginning June 2000 until the end of May 2001. A physical characterization of 274 aeolian sediments were based on grain size distribution analysis and the mineral composition was based on XRD testing of 24 dust samples taken from extreme locations near the Mediterranean Sea and about 800 km inland. An assessment of dust emissions within the area of study, the vertical deposition rates in relation to The Total Ozone Mapping Spectrometer (TOMS) data have been investigated. Moreover, an attempt identify potential Saharan dust emission sources that have impacted the study area has also been made utilizing TOMS data. The area of study has been divided into three regions northern, central and southern according to the dominant factors controlling mobilization of dust particles on the bed surface. This study concludes that deposition rates in the northern coastal region are largely dominated by human activities. Rates in the central region were strongly affected by topographic irregularities whereas in the south deposition rates were less affected by topography and anthropogenic activity. However, deposition rates and particle size distributions are strongly controlled by wind regimes and correlate with the average atmospheric temperatures. Local sediments seem to be strongly affected by saltating particles in most of the study area and no evidence of long range aerosol emission from western Libya was found. Nevertheless, fine dust (<10 gm) is wide spread in the local atmosphere, however it is more pronounced during late spring and summer. TOMS data and the prevailing wind directions reveal that the depressions of the Libyan Desert and the Bodele Depression in Chad were the main sources of aerosol transported over the study area during the highest months of emission, transport and deposition, July and April. It is hoped that this baseline information can pave the way for future studies on dust impacts on soil fertility, human health, desertification, climate change and the validation of present day computer models.

Canals are artificial waterways, which are distinct from natural aquatic systems. As a result of their industrial heritage they have experienced high loadings of anthropogenic material, and consequently their sediments tend to have a bulk composition that is distinct from natural sediment. It is therefore expected that the geochemical behaviour of canal sediment may deviate significantly from that of natural sediment. This study investigates and contrasts the geochemistry and petrology of a rural and urban canal sediment, in order to determine the influence of anthropogenic material upon the urban sediment and to gain an understanding of the diagenetic processes operating within the sediments. Sediment cores were collected from an urban canal in Birmingham and a rural canal in Leicestershire. The cores were analysed at 1 cm intervals in order to build up 24cm depth profiles of their bulk chemistry, metal speciation and porewater chemistry. The petrology of both the sediments was analysed by CryoSEM in order to determine their in situ petrology. The results have shown that the introduction of anthropogenic material to the urban canal has produced sediment that is chemically and mineralogically distinct from natural sediments. The bulk urban sediment contains elevated metal and organic matter loadings, and a significant proportion of its particulate matter is of anthropogenic origin (e.g. slag, fly ash, metal turnings) and is therefore not typical of clastic material in natural sediments. Rural sediment has not been subject to inputs of such material and therefore it has a bulk chemistry of natural materials such as clay, sand, silt and organic matter which is similar to that which is typically observed in natural sediments. The petrological investigation of rural and urban canal sediment has shown that they have distinct authigenic mineralogies. The reduced iron phosphate, vivianite (Fe3(P04)2.8H20) is the most abundant authigenic mineral in urban sediment, as a result of its elevated organic matter and iron concentrations, while in the rural sediment, pyrite (F eS2) is predominant. In order to choose an appropriate scheme for the investigation of speciation in contaminated urban canal sediment, two different sequential extraction schemes were investigated by CryoSEM. The results revealed that they do not yield meaningful speciation results for urban canal sediment. In particular, the application of an oxalic acid buffer to extract oxides resulted in the formation of insoluble oxalates, and the exhaustion of the pH buffering capacity of the extraction reagents used to extract carbonates, resulted in the incomplete dissolution of calcite. The abundance of non-typical sediment components in urban canal sediment highlights the importance of investigating sediment mineralogy prior to the application of sequential extraction techniques. The porewater chemistry was in broad agreement with the observed petrology and, in the case of the urban site, the data provides evidence of sediment disturbance. The periodic resuspension of the sediment by boat traffic results in a significant change to the surface porewater chemistry of iron and sulphate in the urban sediment and results in changes to the stability of certain authigenic phases, most notably vivianite. In the rural sediment, although physical disturbance of the sediment was observed, there was no chemical evidence in the porewater results. However, it does perhaps subtly enhance the organic matter degradation processes that are occurring, although this could not be confirmed by the results of this investigation. The differences in the authigenic mineral assemblages of rural and urban canal sediment are the result of differences in their diagenetic paths. In the rural sediment, the relatively low organic matter and iron loadings result in a diagenesis dominated by sulphate and iron reduction; the abundance of pyrite in this sediment is evidence that sulphate reduction is the predominant process. In the urban sediment, the co-existence of vivianite and iron monosulphides implies that iron reduction is dominating the oxidation of organic matter in the sediment and occurring simultaneously with sulphate reduction. The application of conceptual models of diagenesis, based on porewater studies of natural sediments, can be used to adequately describe the processes that are occurring in the rural canal sediment. However, the periodic physical disturbance and influx of material to urban canal sediment from pollution events prevents the development of steady state conditions. As a result of this, and the nature of the solid material, the diagenetic path observed in the urban sediment is quite distinct from that observed in natural sediments, and simple steady state models are inappropriate for its interpretation.

Well-exposed lower Wenlock sections and borehole sequences, representing various facies along a shelf-basin transect in Wales and the Welsh Borderland, have been sampled for palynomorphs. Primary attention is paid to the type area in Shropshire, including stratotypes of both lower and upper boundaries of the Sheinwoodian Stage, with sampling as close as 10cm through the boundary horizons. The study has been extended into other sequences on the shelf to nearshore facies in the Bristol area and to basinal sections in North Wales. Total organic residues were recovered using quantitative processing techniques and absolute palynomorph abundances were determined. Both transmitted light and scanning electron microscopes were used to work on strew-mounted residues allowing detailed morphological study of the palynomorphs. Techniques were developed for allowing remounting of gold coated SEM cover slips, for transmitted light study and for permanent records. Taxonomic focus is on the acritarchs and the chitinozoans; forty-one acritarch genera and one hundred and seven species and eleven chitinozoan genera and twenty-eight species are systematically described. Ten acritarch species, one chitinozoan genus and three chitinozoan species are new. One genus and species of trilete spore is also systematically described. In addition scolecodonts, graptolite fragments, melanosclerites, chitinous hydroids and amorphous kerogen were recovered and their distribution noted. The exceptionally well-preserved assemblages recovered from the deeper water shelf sections (including the Eastnor Park and Lower Hill Farm boreholes and Whitwell Coppice section) contain 80 2000 acritarchs/g, and 10-60 chitinozoans/g, while the species diversity index (Fisher et al. 1943) for these sections varies between 0.35 and 30.2. The nearshore/shallow water sections (including Tortworth and Dolyhir) yield a well preserved palynomorph assemblage of low abundance (0.024 to 1.14 palynomorphs/g) and low species diversity (0.35 to 3.8). The poorly preserved assemblages of the basin (including the Pistyll Quarry section and the Llanrwst and Conway composite sections) contain 0 to 4.6 palynomorphs/g and species diversity varies between 0 and 4.8. Palynomorph absolute abundances and species diversity are compared and contrasted, both are considerably higher in the inner shelf and shelf sections than in the nearshore/shallow water and outer shelf and basinal sections. Distribution of the organic residues through the different sections is illustrated and discussed and the acritarchs and chitinozoans are used for biostratigraphical refinement. Taxa ranges and relative frequencies are illustrated by computer drafted figures for each section; graphical techniques are also used for correlation purposes as are summary logs of range data. In addition to vertical palynomorph distributional patterns through a studied section, palynomorph assemblage distributional patterns are also discussed and illustrated by graphical representations for the different palaeoenvironments represented by the shelf-basin transect. It is noted that the chitinozoans generally prefer deeper water; on the outer shelf the genera Ancyrochitina Eisenack 1955a and Cingulochitina Paris 1981 and in the basin the genera Sphaerochitina Eisenack 1955a and Conochitina Eisenack 1931 are dominant. With the acritarchs thin-walled leiospheres and shortspined MlchrystrId1um Deflandre 1937 emend. Staplin 1961 appear to have a preference for nearshore/shallow water environments. The acritarchs are most abundant and diverse on the shelf with the acanthomorphs being the dominant group. Basinal sections are dominated by small thick-walled leiospheres and relatively abundant short-spined fat-bodied Veryhachium Deunff ex Downie 1959. Marine and inshore indices adapted from Richardson & Rasul (1990) are also used to highlight assemblage contrasts over the shelf and basin. From the biostratigraphical results a new biozonational scheme for the early Wenlock is proposed, based on the recorded stratigraphical ranges of diagnostic taxa. Three existing acritarch biozones (the Deunffia brevispinosa, Deunffia furcata and Eisenackidium wenlockensis biozones) have their boundaries changed on new stratigraphical range information and one new zone, the Helosphaerldium malvernensis Biozone is proposed. Two new chitinozoan biozones, the Calplchitlna (Densichitina) densa and Clngulochitlna cingulata biozones are also proposed. The palynomorph biozones are related to the established graptolite biozones (see Bassett at al. 1975) in the Whitwell Coppice section and the Lower Hill Farm borehole in the Wenlock type area. The thermal maturity of the different sections is calculated by the use of the Acritarch Alteration Index (AAI) of Legall et al. 1981, which is a method of calibrating palaeotemperatures. For consistency in results only the acritarch genus Leiosphaeridia Eisenack 1958 emend Downie & Sarjeant 1963 was used. For the shelf sections the AAI is low and varies between 2 and 4 (indicating palaeotemperatures of 60-70⁰C ), in contrast the thermal maturity of the basinal sections is much higher, with an AAI of 5 showing palaeotemperatures in the range 90-460⁰C and probably towards the higher end of that range.

The metabasites of the Arendal~Tvedestrand district were originally minor igneous intrusions, but are now characterised by wholly metamorphic mineral assemblages and textures, which are diagnostic of a prograde amphibolite-granulite facies transition. The main mineralogical changes with increasing grade of metamorphism (zone A to zone C) are decreases in modal hornblende and biotite, with increased pyroxenes. Major and trace element analyses for 176 metabasites are presented, and show the overall chemistry to be analogous to that of basaltic rocks. K and Rb vary systematically across the transition zone, declining in abundance with increased grade of metamorphism. In other respects, zones A and B are chemically homogeneous. Zone C (Tromloy) metabasites are characterised by low Ti02, K20, P205, H20, Zr, Ni, Sr, Ba, Rb, and high Na20, (MnO) , Zn, and oxidation ratios relative to the mainland suite. In part, these abundances are related to an original igneous fractionation in which a fairly strong iron-enrichment was accompanied by increased levels of Ti02, P205 and 'incompatible' elements, and decreases in transition trace elements. The relative absence of iron-rich differentiates in zone C accounts for the lower levels of P205 and Ti02 in this zone. Secondary fractionation accompanied the metamorphism, and resulted in K and Rb redistribution throughout the terrain and the Na20 enhancement in zone C. Ba, Sr and Zr appear to be depleted in this zone. These chemical changes are also noted in the acid- intermediate charn-ockitic suite of the transition zone, which is genetically distinct from the metabasites. 'Stable' element discrimination diagrams, ( when used with caution in view of these fractionation patterns) show the suite to be originally tholeiitic. Preliminary microprobe data support the concept of chemical equilibrium in the metabasites. Almandine-rich garnets are sporadically developed in the suite, and their growth is not directly related to the host-rock chemistry.

The diagenetic history of the Oolite Group from Pwll du to Blaen Onneu has been unravelled. Cement types, solution events, dolomitisation, concretions and other authigenic minerals are described. The calcite cement crystals show chemical zonation through staining but cathodoluminescence (CL) has proved the most useful method for displaying internal features of calcite crystals. CL makes it possible to trace the growth of crystals and monitor changes in crystallographic form during growth. Seven cement zones are identified using stained specimens. Each zone has a characteristic luminescence. The age of these zones relative to the exposure of the top of the Oolite Group is established. Two distinct diagenetic areas are recognised on the basis of the distribution of the cement zones. Area 1 : the Pwll-y-cwm and Blaen Onneu Oolites in the Clydach area, in which Zones 1, 2b and 6 are present, Area 2 : the rest of the Oolite Group, in which Zones 2a, 3, 4, 5 and 6 are present. It is possible to correlate the cement zones of Area 2 along the outcrop for a distance of 8 km and also with cements in the overlying Llanelly formation. Oolomitisation prevents correlation of cements in Area 1 over a distance of more than 1/2 km. Using CL it is possible to identify solution surfaces, on a micron to millimetre scale, within the cements. four solution events are identified in Area 2. Solution affects that are previously unreported are described. The presence of solution surfaces is used to illustrate the constantly changing nature of the pore waters that have affected the Oolite Group. Carbon and oxygen stable isotope analysis of allochems and cement zones highlights the distinction between Areas 1 and 2 and are used to try and identify the nature of the pore waters affecting the Oolite Group during its diagenesis. The carbon isotopic composition of the allochems and cements pre-dating the exposure of the top of the Oolite Group is related to their distance below the exposure surface at the top of the Oolite Group and thus seems to reflect meteoric alteration. The successive cement zones do not show a progressive trend in caroon and oxygen values; however, in different samples successive cement zones do show the same pattern of changes in carbon and oxygen values. The values typical of a specific cement zone are thought to relate to the pore fluids from which it was precipitated. The pattern of changes seen in successive cement zones is explained in terms of changing pore water chemistry and isotopic composition with time. These changes occurred over an area at least the size of the study area. Very light oxygen values in veins are attributed to increased temperatures associated with deep burial. An attempt is made to reconstruct the paleohydrology of the study area in an attempt to explain the nature and distribution of the cements.

The Lizard Complex consists of a poorly exposed assemblage of serpentinites, gabbros, amphibolites, basic dykes, metasediments and gneisses. As an alternative approach to conventional mapping of the inland area, the geochemistry of the residual soils of the area are used to identify the underlying lithologies. Using multi-element geochemical data obtained by X-ray fluorescence spectrometry, an identification scheme is established which allows the recognition of over a dozen mappable units with a high rate of success. This scheme evolved from a training set of samples collected during an orientation survey from areas of undisputed geology immediately adjacent to coastal exposure. At approximately 250 sites it has been possible to confirm the geological predictions directly against material obtained from the base of power auger holes. A non-hierarchical K-means clustering technique is developed and used to recluster data from over 800 samples into gabbroic and ultrabasic groups. The results of this classification produced more sensitive discriminatory parameters which in turn are used on 1500+ samples collected during the project. The soil identification procedure combines the use of a variety of numerical techniques and the algorithm designed to use them operates in a sequential manner. The most distinct units are identified at an early stage whilst those samples which are less distinct chemically take longer to isolate and as a final stage of treatment are separated using a modified K-means technique. This approach to mapping has allowed the recognition of units not found outcropping on coastal sections and for an improved geological map of the Lizard Complex to be drawn. In particular the Crousa gabbro is shown to be a smaller body than previously considered and to comprise several different bodies. As a result of this work the evolutionary history of the Complex is revised.

The Emet borate deposits are shown to be older and mineralogically more complex than previously thought. They are considered to have formed within the muds of separate or interconnected playa lakes, in areas of volcanic and seismic activity, fed partly by thermal springs and partly by streams draining the catchment areas, under arid or semi-arid climatic conditions during the Middle Oligocene. The borate minerals formed in two geochemically distinct sedimentary basins and are interbedded with limestone, marls, volcanic tuffs and clays, much of which appear to have been derived mostly from a volcanic terrain. The borates show mineralogical and geochemical features in the two basins which are sufficiently different to suggest that the chemical compositions of ground and surface waters in the two basins differed at least from time to time. Basement metamorphic rocks and Tertiary limestone might also have been exposed and erosion of these may have contributed Ca and Sr to the lake waters. Sediments in the borate lakes are cyclical with both lateral and vertical facies changes. The clastic sediments in both basins are similar but are very much thicker in the northern basin. The total Tertiary sedimentary thickness exceeds 750 metres. The borate zone varies in thickness between 0-100 metres and reaches its maximum thickness in the northern deposits. The Middle Oligocene sedimentary formations, including the borate zone, are far more faulted than previously thought. Thermal springs, which at present deposit travertine and sulphur, are active and widespread west of the Emet River. Colemanite predominates and occurs in many different forms. Other borates include meyerhofferite, ulexite, tunellite, teruggite, cahnite, hydroboracite and either veatchite or p-veatchite. Cahnite has not hitherto been identified from borate deposits. Calcite, gypsum, celestite, native sulphur, realgar and orpiment are the principal associated minerals. Montmorillonite and illite are the only clay mineral groups identified. Volcanic rocks, closely related to the Middle Oligocene lacustrine sediments, range from rhyolites to basalts and are very rich in potash relative to soda. A complete transition exists between tuffs and clays in the Emet borate zone sediments and is reflected in their geochemistry. All tuffs, clays and limestones are characterized by a relatively high concentration of B, As, S and Sr, and high Fe203:FeO ratios which indicate strongly oxidising conditions of sedimentation, with a very low rate of leaching. The deposits are characterized by high Ca borate (colemanite), very low Na, poor Cl and relatively high Mg, Sr, As and S concentrations compared with other borate deposits. Like the sediments, the borates are also characterized by a relatively high Fe203:FeO ratio, suggesting strongly oxidising conditions of precipitation. The geochemical investigations suggest that the most likely sources of B, As and S were from the Tertiary volcanic rocks and associated thermal springs. The major sources of Ca, Mg and Sr are considered to be due to leaching of underlying basement rocks and Tertiary limestone by thermal springs. Investigation of the genesis of colemanite reveals no field evidence to unambiguously support its formation by replacement of ulexite or dehydration of inyoite after burial. The early colemanite nodules were probably formed directly from brines, penecontemporaneously within the unconsolidated sediments below the sediment/water interface, and continued to grow as the sediments were compacted. Possibly the brines were never sufficiently concentrated to allow borate precipitation until the lakes were partially or wholly dried up. Later generations of colemanite occur in vughs, veins and as fibrous margins to colemanite nodules. Other diagenetic changes include the partial replacement of colemanite by hydroboracite, calcite, cahnite and a veatchite mineral. When weathered, colemanite is often almost completely replaced by calcite. Realgar, celestite and sulphur appear to have been deposited both during and after the formation of the borates. Quantitatively known reserves in the Emet district are more adequate but their quality is less assured. The presence of arsenic in both the sulphide and borate phases can present problems during mineral processing. However, the Emet borates are high-grade colemanite deposits and should supply a substantial quantity of the world's needs for many years.

Samples collected from mid-Ibexian (mid-Tremadoc) to late Whiterockian (Llandeilo) of East and eastern North Greenland have yielded a total of 9,725 identifiable conodont clements. The conodonts are referred to 54 multi-element genera and 115 species, new taxa include three genera (Macheticodus, Wandelia and Wcbcrina) and nine species (Eucharodus apion, Macheticodus lekiskus, Multioistodus? celox, Pteracontiodus armillatus, Scalpellodus? narvhalensis, Sibiriodus? kalalekus, Wandelia fuscina, Weberina candidisphaera and Weberina guyi). The faunas are coniform-dominated and generally similar to shallow water, Midcontinent Province faunas found in North America. Some degree of endemicity is indicated by the presence of species found only in the eastern Canadian Arctic Islands and Greenland. The conodonts are referred to ten biozones, of which three zones in the Ibexian are newly named (the Loxodus bransoni, Glyptoconus quadraplicatus and Oepikodus communis Zones) as are three Ibexian sub-zones (the Acodus deltatus,?Reutterodus andinus and Protoprioniodus aranda). These are all based on the previous, informal faunal divisions established in North America. In East Greenland, the oldest faunas recovered, from the base of the Cape Weber Formation on Ella Ø, are referred to the L.bransoni Zone (mid-Ibexian). Both upper and lower boundaries are, however, diachronous and on Albert Heim Bjerge, 150km to the north, the base of the formation contains conodonts of the younger G.quadraplicatus Zone. On Ella Ø, the lbexian-Whiterockian boundary occurs within the lower part of the Narwhale Sound Formation and the youngest conodonts recovered are referable to the Histiodella altifrons Zone (early Whiterockian). The youngest Ordovician conodonts recovered from East Greenland are from the Heim Bjerge Formation, directly underlying Devonian conglomerates, on C.H.Ostenfeld Nunatak; these faunas contain taxa of the Polyplacognathus sweeti Zone (late Whiterockian). In eastern North Greenland, the Wandel Valley Formation unconformably overlies Cambrian carbonates, and conodonts recovered from the base probably belong to the O.communis Zone (late lbexian). The Ibexian-Whiterockian boundary lies at or just above the lower boundary of the Upper Member and the top of the formation contains taxa referable to the Polyplacognathus friendsvillensis Zone (late Whiterockian). Contouring of the colour alteration indices (CAl) in North Greenland indicates that the isotherms are parallel to the margin of the Hazen Trough; to the east, in Kronprins Christian Land, they swing around to become parallel to the Caledonian front. Fused clusters recovered from the Cape Weber and Heim Bjerge Formations are amongst the oldest euconodont assemblages recorded. They are principally of coniform species and suggest a grasping function analogous to that of chaetognath spines.

The area is part of the north-west Jotunheim mountains in southern Norway and consists of three rn.ain rock units; Granitic rocks of the Basal Gneiss Corn.plex outcrop in the north of the area; supracrustal rocks of presumed Eo-Cambrian to Ordovician age in the central part and the Upper Jotun Nappe outcrops in the south. Previous work in the area (mainly by Nottingham workers) had shown that the supracrustal rocks were thrust onto basal gneisses. The detailed structure of the supracrustal rocks, the relationship of the Upper Jotun Nappe to underlying rocks and structure and the metamorphic history were unknown and little detailed petrography and chemistry of the supracrustal rocks had been carried out. The writer, by means of detailed structural analysis, with petrographic, chemical and mineralogical studies, has attempted to reconstruct the detailed metamorphic and structural history of the supracrustal rocks. The stratigraphy and a description of the lithologies with field relations, petrography and chemistry are given and a special study made of amphibolites and dunite-serpentinites. The structure of the area is complex; Pre-Cambrian structures from the Basal Gneiss Complex and Upper Jotun Nappe and five phases of Caledonian deformation (excluding joints) are recognised. Orientation and symmetry of folds are discussed. Occurrences of conglomeratic structures are described; these are B-tectonites, essentially tectonic inclusions formed by disruption of continuous layers. A quantitative study of fold styles is presented and folding is discussed in kinematic terms; the second Caledonian deformation (BZ) is complex. A movement picture is suggested for each main phase of deformation. A quantitative fold description is considered and BZ folding is discussed from theoretical and experimental points of view. The metamorphic history of the area is described; three Caledonian metamorphisms and several Pre-Cambrian phases described. A tentative geological history is presented and some of the broader aspects of the work discussed. Mineral analyses are presented and a brief description of the methods used given.