This thesis examines how microstructures in glaciogenic sediments reflect the processes forming them, and how these microstructures then affect the conditions around them, through a series of field studies, laboratory tests, models, and statistical analyses. Following literature reviews, a deformational chronology is developed for diamictons at Criccieth, North Wales, and their microstructures are used to indicate the stress, hydraulic, and environmental changes the materials have undergone. Microstructures of the lowest diamict indicate clast lodgement. The processes reflected in the microstructures of this lowest diamict are built into a quantitative model that estimates its residual strength (20 - 50 kPa) and the ice velocity during lodgement (20 - 50 m a-1). The response of sediment to glacial stress is further examined by triaxial testing of diamict from Yorkshire, and the subsequent examination of its micromorphology. Shears in the material are disrupted by clasts, and this may be responsible for work hardening seen during the tests. Fabric compression, and the development of immobilised shears or hydraulic fractures buffer pore fluid pressure to ~470 kPa. The information from previous chapters is then used to analyse other material from the Yorkshire coast. This analysis confirms the presence in the area of meltout tills that have undergone low strain, as well as providing evidence for the decoupling of the ice and sediment in this region, and the nature of drainage systems within and above the diamicts during glaciation. Overall this thesis details the processes forming three ‘classic’ microstructures found in glacial sediments; omnisepic fabrics, lattisepic fabrics, and melanges, and provides evidence for the processes involved in forming diamict pebbles and skelsepic fabrics. In addition this thesis details how such structures reflect coupling and decoupling processes between glaciers and their beds, and examines the manner in which microstructures affect the response of a subglacial sediment body to stress and hydraulic conditions.

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Cycling of nutrients, such as Carbon (C) and Nitrogen (N), is one of the most important soil functions and is strongly related to the composition of the soil microbial community. However, soil is increasingly under environmental pressures that threaten its ecological functions and sustainability. To maintain soil functional sustainability, it is important to understand how soil withstands environmental stresses (subsequently referred to as resistance) and recovers from stresses (subsequently referred to as resilience). This study focused on the resistance and resilience of C and N processes and the underpinning microbial communities to a persistent Cu stress or a transient heat stress. The main advances and novel findings of this thesis are: (1) C mineralization is more resistant and resilient than ammonia oxidation and denitrification, and thus the combination of C and N processes are more informative than measuring a single process to interpret the overall resistance and resilience; (2) microbial composition and microbial physiological evolution play important roles in affecting resistance and resilience; (3) soil physico-chemical properties (e.g. organic matter, soil water and soil pH) are critically important in conferring resistance and resilience. The outcome of this study advances the understanding of the mechanisms of soil resistance and resilience of C and N cycling to environmental changes. The results generated here are an essential step for improving soil sustainability and promoting agricultural productivity under future environmental challenges.

From a geomorphological point of view, and environments are characterised by complex process interactions and suites of landforms which can be sensitive to their controlling parameters. Relationships between sediment, moisture and soil crust characteristics are no exception. Field research and a programme of laboratory study were undertaken between 1993 and 1995 on the soils of the northern Badia of Jordan to advance knowledge on aspects of and zone soil dynamics, with a particular emphasis on crusting. The research focuses primarily on the effect soil crusts have upon the equilibrium of sediment dynamics at a hillslope scale and a ridge-furrow scale. The implications of the crust upon moisture storage within the surface layers of the soil are examined and the spatial characteristics which arise due to management practices and climate variables considered. A new, non-destructive dielectric technique to investigate moisture content in dryland soils has been developed and tested. Monitoring has taken place to examine the effects of irrigation upon the surface characteristics of the surrounding soil, with special reference to evaporation fluxes within a furrow and the associated precipitation of salts. The role of small-scale topography tends to be underestimated. Different types of crust have been studied from various topographic locations. Soil fabric and porosity have been studied, to increase understanding of micro-scale depositional and erosional processes. A new method of tracing' fine material through the upper soil profile has been developed. As crusts form, the tracer can be used to monitor the movement of fines, permitting a much clearer understanding of soil and water dynamics as a result of rainfall events.

ABSTRACT A comparative morphological study on the leaf of Melastomataceae was made for 21 species of 11 genera in Taiwan. The morphological characters studied include leaf venation, trichome, epidermal cell, anticlinal wall, stomatal type and crystal type. The results are given as follows. Two types of venation are recognized, i.e. pinnate and palmate venations. The leaves of all species showed their palmate venation except for those of Memecylon lanceolatum. Seven types of trichrome could be observed in the studied species, which consist of peltate scales, bladder-like glandular hairs, multiseriate unbranched hairs, multiseriate unbranched glandular hairs, short-stalked glandular hairs, armed hairs and stellate with glandular hairs. All of species have short-stalked glandular hairs occurred on the leaves of all species except Memecylon lanceolatum which has no trichrome at all. In addition, bladder-like glandular hairs on upper epidermis of leaves in Medillia and on both epidermis of leaves in Blastus. The epidermal cells of the leaf surfaces are polygonal or irregular in shapes, and the anticlinal walls are straight, arched, repand and sinuous. There are five types of stomata, which are composed of anomocytic type, diacytic type, paracytic type, polocytic type and staurocytic type. Only Melastoma kudoi and Osbeckia chinensis have stomata at upper epidermis. Two kinds of crytals appeared, i. e. styloids and druses. However, the occurrence of crystal is unstable specifically and generically, which implies that it is invaluable for specific and generic delineation. Additionally, druses could be found epiphytic on multiseriate unbranched hairs of the genera Melastoma and Osbeckia. According to this study, the features of leaf venation, trichrome, epidermis cell, anticlinal wall and stomatal type could provide evidence for taxonomy of this family.

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Yes / The biographical approach has become a well-recognized and adopted method to theorize the establishment and development of settlements in accord with their human occupation. Recent proposals for such a biographical model for the lake-dwellings of the northern Alpine region have been largely based upon theoretical and hypothetical considerations. Lake-dwelling sites in the Alpine region generally have excellent levels of organic preservation, particularly for artefacts and building foundations, but with poor representation of building superstructures. They do however have high potential for archaeology micromorphological soil analysis, with sediment deposits providing indications of both human activity and environmental conditions within the settlement. Using specific examples from Switzerland, this paper intends to highlight some of the contributions that micromorphology can provide to the consideration of settlement biographies. / Swiss National Science Foundation

This project documents the multi-scalar formation processes of two northern Levantine coastal Paleolithic cave sites using field geology, archaeological micromorphology and sediment geochemistry. Located in within several hundred meters of each other, the sequences from Üçağızlı I and II present an opportunity to compare late Middle and early Upper Paleolithic hominin adaptations to a similar coastal environment. The morphologies of the sites and the suite of coastal geomorphic features available to the area's Paleolithic occupants were impacted by fluctuations in sea level as well as tectonic events. The sites share similar formation histories that include active karstic processes, marine inundation, occupation by hominins, partial collapse of the cave vaults, and erosion of the uppermost archaeological deposits. Mousterian occupation of Üçağızlı II began after the formation of a series of stable sea level features that date to Marine Isotope Stage (MIS) 5a. Hominin utilization of the highly eroded portions of the cave continued at least through the middle of MIS 3, although the cultural attribution of the youngest materials is presently unknown. Üçağızlı I contains a sequence of Initial Upper Paleolithic, Ahmarian and Epipaleolithic materials dating to MIS 3 and 2. Micromorphology of the archaeological sediments reveals strong anthropogenic contributions to the infilling of both caves, in particular the deposition of abundant, well-preserved wood ashes. In both sequences, post-depositional insect bioturbation has negatively impacted the combustion features, resulting in alteration of the original sedimentary fabrics and loss of information regarding hominin activities such as sweeping, rake-out and dumping of ashes. In Üçağızlı II, the dominant mode of sedimentation is anthropogenic; a series of intact and cemented combustion features located beneath the highest point of the cave ceiling is surrounded by sediment exhibiting evidence of both rodent and insect bioturbation. In Üçağızlı I, phases of human activity alternated with periods of natural sedimentation. Combustion features in the site include isolated hearths, stacks of hearths, rake-out or sweeping deposits, ash dumps, and mixed burned materials that have been impacted by colluvial reworking and bioturbation. In sum, the two sites contain similar types of anthropogenic sediments despite differing cultural affiliation.