Collapse is part of the growth cycle of volcanoes with active rift-zones. As the volcano develops and grows disequilibrium between the strength of the edifice and the applied stresses, produce instability within the edifice which can potentially lead to catastrophic lateral collapse. The intra-eruptive periods on persistently active volcanoes are often short-lived. The recent intra-eruptive windows at Piton de la Foumaise, Reunion Island (1994-1996), Etna, Sicily (1994-1997) and the less-frequently-active Cumbre Vieja ridge on La Palma (1994-1998), have provided a valuable opportunity in which to compare the background deformation (which can indicate whether the edifice is stable between eruptions). Influences such as gravitational loading, tectonic activity, creep or the intrusion of fresh magma would cause coherent deformation patterns, and even small movements within the estimated errors of the measuring techniques are assessed over time to identify patterns. For each site the background seismicity has remained low and no flank eruptions were recorded during the monitoring program. The results suggest that each site is stable between eruptions. Etna has shown increasing activity since 1995 reflected by a general pattern of inflation. This inflation and a small isolated pocket of inflation on the SW flank are attributed to the intrusion of magma in 1995. A coherent pattern of very minor deformation was observed spanning the 1949 fault of the Cumbre Vieja from 1994 to 1997, however, this was not sustained in 1998. Piton de la Fournaise remained stable during the monitoring program and then erupted at the end of the study in 1998. This inter-eruptive period also provides an optimal time for the transition from one technique to another. On each site the existing EDM (Electronic Distance Measurement) networks were re-occupied using GPS (Global Positioning System), the comparison of individual vectors indicated that the accuracy was approximately 5-12mm, which was less than the expected error between EDM surveys. The networks at all sites have been expanded during the quiescent period and the use of GPS has permitted the optimal positioning of survey stations in order to assess future ground deformation.

Water is a politically sensitive resource in the Near East and water stress is increasing. It is therefore vital that there is a strong understanding of past hydrological variability, so that the drivers of change can be better understood, and so that the links between the palaeoclimate and archaeological records in this key region in the development of human civilisation can be investigated. To be of most use, this requires high resolution records and a good understanding of palaeoseasonality. A sediment sequence spanning ~14,000 years has been retrieved from Nar Gölü, a lake in central Turkey. This thesis presents isotope data from carbonates, diatoms and bulk organic matter, in particular focussing on oxygen isotope (δ18O) analysis of carbonates (which detailed monitoring of the modern lake system shows to be a strong proxy for water balance) and comparing δ18Ocarbonate and δ18Odiatom data in order to examine palaeoseasonality. Improved techniques for the interpretation of carbonate isotope records of mixed mineralogies and the mass balance correction of diatom samples contaminated with minerogenic material are also proposed. Due to the high resolution δ18Ocarbonate data, it was possible to show that the rapidity of the Younger Dryas to Holocene transition at Nar Gölü was similar to that seen in North Atlantic records and that centennial scale arid events in the Holocene seem to occur at the time of cold periods in the North Atlantic. Taken together, this suggests a strong teleconnection between the two regions. However, the longer duration of the aridity peaks ~9,300 and ~8,200 years BP at Nar Gölü, compared with the more discrete cooling events at this time in the North Atlantic, suggest that there are additional controls on Near East hydroclimate. There is a multi-millennial scale trend of increasing δ18Ocarbonate values from the early to late Holocene. This ‘Mid Holocene Transition’ has previously been identified in the Near East, however here it is demonstrated that water balance and not a shift in the seasonality of precipitation was the primary cause. Finally, for the first time, the stability of Near East climate in the early Holocene is robustly demonstrated, suggesting that this could have been a key enabler of the development of agriculture at this time.

This thesis uses data sets at a range of spatial and temporal scales to examine the geomorphological response of the Lower Mississippi River to engineering and management. During the twentieth century the geomorphology of the Lower Mississippi River has been transformed by a series of engineering modifications to improve flood control and aid navigation. These have included steepening of the longitudinal profile by removal of the most sinuous bends, fixing the river to a constant planform through extensive bank stabilisation, and regulating sediment movement through the channel system by dike field construction. Prior to these modifications, the Lower Mississippi River adjusted its planform morphology to satisfy large-scale flow resistance requirements. However, this mode of adjustment has been effectively removed and adjustments are now restricted to the long profile and cross-sectional form. Morphological analysis reveals that the river has responded to engineering intervention at two principal scales: by vertical changes in the elevation of the channel bed at the reach-scale; and by increasing large-scale bedform resistance at the sub-reach scale through longitudinal and cross-sectional adjustments. These mutual changes are consistent with the changes in water surface elevation in the post-modification period noted by Biedenharn and Watson (1997). However, analysis of morphological and process dynamics at shorter timescales shows that geomorphological response remains difficult to explain. This is because geomorphological behaviour at any scale, and in any location within an alluvial channel, is a product of complex spatially-distributed feedbacks between operating processes and multiple scales of channel morphology. This has general significance in terms of research design because detecting the complexity at each scale of adjustment, and forming linkages between scales of adjustment, is dependent on taking into account all possible degrees of freedom, and applying a range of complementary analytical techniques.

The history of Catholicism is an essential component in the history of modern Ireland. As locations of a distinctively Catholic faith, Mass Rocks are important historical, ritual and counter-cultural sites. Their continued use reflects, and helps reconstruct and legitimise, contemporary Irish identity whilst providing a tangible and experiential connection to Irish heritage and tradition. The mythology surrounding Mass Rocks tends to symbolise the worst excesses of the ‘Penal Laws’. Yet, as Elliott (2000) has pointed out, the impact of the Penal Laws was short-lived and the worst was over by 1730 (Elliott 2000:170). Since the 1990s, most historians have rejected this traditional ‘penal’ paradigm with its subtext of a heroic but silenced Catholic nation (Dickson 2004:38). Yet, the Irish countryside remains littered with the Mass Rocks that were used throughout this period and they are still considered to be special and sacred places. Using a framework of sacred space this research provides an original and important vista on this topic. An examination of their geographical distribution has yielded some surprising concentrations and absences in certain areas. The actual locations of these sites have proved equally intriguing since few appear to conform to the mythical, secluded, upland sanctuaries depicted in early and mid-twentieth century history textbooks and more recently on ‘republican’ murals. This research does not attempt to assess the implementation, success or failure of the Penal Laws. However, it does provide one of the most thorough syntheses of available information in respect to Mass Rocks at a diocesan level and therefore provides a valuable resource that will help widen knowledge of this emotive and often misunderstood period. Research has been based in the diocese of Cork and Ross, county Cork. The parish of Uíbh Laoghaire or Iveleary, the county of Cineal Laoghaire or O’Leary, is located within this diocese and is relatively rich in Mass Rock sites. The parish of ‘Inshiguilah’ or Inchigeelagh is referenced within the Report on the State of Popery of 1731 along with adjoining parishes. Its sound pedigree in terms of its historical, geographical and cultural background made it an excellent candidate for a case study. It offered a valuable opportunity to apply the conceptual framework of sacred space to a specific parish within the research area in order to evaluate the validity of the research findings. Although much has been written about the Penal era, the study of Mass Rocks is a neglected area of study and it is hoped that these results will help to frame Eighteenth-century Irish Catholicism within a broader economic, social, cultural and political context.

Fire has not always been so elusive in the northern European forest yet forest management and active fire suppression has created an ecosystem almost free of fire. This absence of fire is thought to have contributed to the widespread dominance of Picea abies as well as the decline in deciduous species and subsequent loss of floristic diversity. Forest fires in general are driven by a complex interplay between natural (climate, vegetation and topography) and anthropogenic disturbance and through palaeoecology we are able to explore spatio-temporal variability in the drivers of fire and changing fire dynamics. This thesis explores spatial and temporal variability in Holocene vegetation and disturbance dynamics through stand-scale palynology. Pollen and macroscopic charcoal are used to reconstruct past vegetation and fire dynamics with local- and regional-scale pollen-derived quantitative vegetation reconstructions able to identify both large-scale ecosystem response and local-scale disturbance. Spatio-temporal heterogeneity and variability in biomass burning is explored to identify the drivers of fire and palaeo-vegetation reconstruction is compared to process-based, climate-driven dynamic vegetation model output to test the effect of fire frequency as a driver of vegetation composition and dynamics. Early-Holocene fire was driven by natural climate variations and fuel availability. The establishment and spread of Picea abies (Norway spruce) appears to be driven by an increase in continentality although local disturbance cannot be ruled out. The expansion of Picea led to a step-wise reduction in regional biomass burning and the now widespread dominance of Picea abies is responsible for the low fire frequency observed through Fennoscandia. The mid-Holocene decline in deciduous species was primarily driven by localised anthropogenic disturbance and may have been assisted by the shift to cooler, wetter climate conditions. There is an underlying natural fire frequency of approximately 400 years observed in southern Finland and without intensive anthropogenic disturbance floristic diversity may have remained locally, to the present day. Stand-scale palynology is able to record past local disturbance at a high spatial precision however more than one site is required to understand regional disturbance and the variable controls of fire dynamics.

Surface Flow Types (SFTs), distinctive patterns of disturbance on the surface of flowing water resulting from the interaction between flow and channel shape, were used to delimit meso-scale in-channel habitats in eight British lowland rivers to determine whether SFT mesohabitats were capable of being mapped, and were physically and biologically distinct. Five different SFTs - No Perceptible (NP), Smooth (SM), Rippled (RP), Unbroken wave (UW) and Upwelling (UP) - were investigated, a further three rare types (Chute, Broken wave and Confused) were mapped but not investigated further. Identification and mapping the extent of SFTs of was shown to be practical by estimating SFT mesohabitat extent onto large scale plans of the stream channel supported by differential Global Positioning Satellite technology. Mesohabitats were drawn as they existed, giving a large degree of variability in relation to channel shape and improving over several current rapid habitat mapping methods. The physical distinctiveness of five SFT mesohabitats was examined using data collected from 596 mesohabitats over a wide range of discharges. Mean column velocity and substrate grain size (dominant and sub-dominant) increased from NP, through SM and RP to UW. Velocity, substrate size and embeddedness of fine particles were significantly different (ANOVA and Pair-wise) between the five SFTs investigated. Substrate size was positively associated with increasing velocity, depth and embeddedness were negatively associated with velocity. PCA showed that substrate opposes embeddedness and velocity opposes depth. The degree of distinctiveness was diminished by data ranges which encompassed several SFTs. Macroinvertebrates were collected in 375 samples from 139 SFTs, using one-minute kick samples and identified to Biological Monitoring Working Party family level. ANOVA and Pair-wise analysis of Lotic-invertebrate Index for Flow Evaluation Velocity Group shows significant differences between 80% of SFT combinations with UP least distinct. Mean relative abundance and taxonomic richness increased from NP, through SM and RP to UW and were positively related to velocity. ANOVA showed significant differences between relative abundance and richness in SFTs, whilst Pair-wise analysis shows that adjacent SFTs, in relation to velocity, were less different than those further away. Thus NP is similar to SM and different to UW. Diversity and Equitability between SFTs were less distinct. Thirteen macroinvertebrate family groups were significantly associated (X2 Test) with particular Surface Flow Types, e.g. Ancylidae with UW; Chironomidae with NP. Biological distinctiveness was not established, although general trends were identified One mesohabitat – UP - is rare, being physically related to NP and SM in depth and substrate, and to SM and RP in velocity and embeddedness. It is biologically less distinct than the other four SFTs. The research shows that the extents of NP, SM, RP and UW mesohabitats in British lowland rivers are capable of being mapped. There are significant trends in their physical distinctiveness which are linked to increasing downstream velocity although is not strong. The macroinvertebrate relationship is weaker, with abundance and richness increasing with velocity.

Accurate characterisation of the hydraulic environment is a key step in describing hydromorphology at an ecologically relevant scale which has relevance to several aspects of river management, including monitoring river health, designing environmental flows and evaluating river rehabilitation measures. However, current hydraulic habitat quantification methods oversimplify the spatial heterogeneity of the hydraulic environment and do not explain or interpret the spatial arrangement of different habitat units sufficiently or define the dynamics of these shifting patterns. This research applied a novel numerical classification method and a landscape ecology framework to quantify the composition and configuration hydraulic patches in three UK lowland river reaches at five different flows. Five spatially coherent hydraulic patches, defined by the joint distribution of depth-velocity, were optimally delineated from hydraulic point data at each reach using the Gustafson-Kessel fuzzy clustering algorithm. Transitional zones between hydraulic patches occupied between 18- 30% and represent an application of the ecotone concept to the instream environment. Hydraulic patch diversity increased with discharge, peaking at high flow (Q38-Q22), suggesting that the provision of high flows is important for maximising hydraulic heterogeneity. The dominance of shallow, slow patches at low flow was gradually replaced by faster, deeper hydraulic patches at high flow illustrating the effect of discharge on the availability of different hydraulic patch types. The spatial arrangement of patches, quantified using a range of spatial metrics from the field of landscape ecology at two spatial scales (class and reachscape), was relatively invariant to changes in discharge suggesting that the configuration of the hydraulic patch mosaic is determined by channel morphology and remains stable between channel forming discharges. The majority of hydraulic patch types occurred in relatively fixed locations in the channel, moving relatively small distances as discharge increased, associated with the gradual expansion or contraction of patch area. The results suggest that sub-bankfull flow variations will primarily affect the composition rather than the configuration of hydraulic patches, however large fluctuations are likely to result in high rates of patch turnover (change in location), with potential implications for instream biota. The hydraulic patch/transition zone model of the hydraulic environment provides a new approach for exploring the link between physical and biological heterogeneity in the instream environment, including the role of instream ecotones. Whilst the application of numerical classification is currently limited by the large hydraulic data requirement, future advances in remote-sensing technology and hydrodynamic modelling are likely to widen its iii applicability at a range of spatial scales. The results highlight the need for further research on the ecological significance of hydraulic patches and transition zones and ecological sensitivity to changes in hydraulic patch configuration. Wider application of the landscape ecology approach to hydraulic habitat assessment in different reach types is recommended to improve understanding of the links between geomorphic and hydraulic diversity.

A meandering river is one which exhibits a serpentine course, formed by a series of alternating bends connected by short, relatively straight reaches. Meandering behaviour has been found to be ubiquitous in alluvial streams and rivers. The tendency of the bends in meandering rivers to evolve and shift is a natural outcome of interactions between the flowing water, sediment in transport and the resistance to erosion of the boundary sediments. The resulting formation, evolution and shifting of bends is intrinsic to the morphological behaviour of meandering, alluvial streams. The need to understand and predict this behaviour stems not only from the desire to explain the morphodynamics of meandering rivers, but is also required to manage down the risks to property and infrastructure located along the course of meandering rivers, as well as the people who live, work or travel in the vicinity of alluvial streams with meandering planforms. In this context, the aim of this research is to develop an original, scientifically-based, and practical approach to the risk-based prediction of the hazard associated with bend migration that accounts for the uncertainty inherent to the morphological behaviour of rivers. A database compiled for the National Cooperative Highway Research Program (NCHRP) was used as the primary source of data. This includes data for 1,505 bends taken from 125 locations on 89 rivers spread across 24 States.in the USA The rivers were classified into nine categories of meandering, based on a modified Brice Typology. Bend geometry data in the database were measured from aerial photographs and maps representing the bends in the 1930/40s, 1950/60s and 1990s. It has long been recognised that the dimensionless rate of bend migration (M/W) is related to the stage of bend evolution (initiation, growth, translation, termination) and that this can be represented by the ratio of the bend radius of curvature to the channel width (R/W). It was decided to analyse bend migration based on these parameters and use the dimensionless form of the bend radius as the independent variable in the probabilistic analysis. Using normal conditional density functions fitted to the data, rates of meander migration were estimated corresponding to: 50%, 60%, 75%, 80%, 90%, 95%, 97%, 98%, and 99% probabilities of not being exceeded. The risk associated with a hazard depends not only on the probability that it will occur but also the consequences should it do so. In selecting the acceptable level of probability that the predicted rate of migration will not be exceeded, care should therefore be exercised by the user in considering all the possible consequences should this occur.

Algorithms and data structures for presenting geographic data on a raster display are described. / A new algorithm MAPFILL quickly renders color-coded thematic maps. The use of MAPFILL to render both contour maps and choropleth maps is described. Some variant versions of MAPFILL provide anti-aliasing, while others provide pattern-fill capabilities. Generalized forms of MAPFILL color map regions with elements from an abelian group. A method of extending the algorithms to render not only maps in the plane but also maps of the whole earth is explained. / Also described is a hierarchical vector-type cartographic data base design which allows efficient selective rendering of border detail. / A software system called GeoGraph, developed by the author, implements many of the proposed algorithms. This software is described from the point of view of both a new user and a programmer. / Source: Dissertation Abstracts International, Volume: 51-09, Section: B, page: 4450. / Major Professor: Robert Christopher Lacher. / Thesis (Ph.D.)--The Florida State University, 1990.

The potential factor of Mesolithic impact on the vegetation of south-west Scotland from c. 10 000 - 5000 b. p. was investigated by pollen and charcoal analysis of small peat-filled basins and blanket peat near to the sites of lithics and in the context of subsequent vegetational history (from c. 5000 b. p.). Attention focused on upland sites by Loch Doon and Loch Dee. Upland areas by Clatteringshaws Loch and a site at Palnure near the coast provided a late and relatively incomplete record respectively. Two cores were collected at each of Loch Doon and Loch Dee to enable comparison of microfossil stratigraphies. At Loch Doon several cores were analysed across the rise in Alnus. Preliminary counts were made from a core from Loch Doon itself. Radiocarbon dating gave additional confidence to the chronological framework. The availability of comparable pollen data enabled some distinction between local and more regional vegetational events. The charcoal profiles were more problematical to interpret, but the contrast between a very low level of charcoal prior to a rise in the early postglacial (Fl I) at both Loch Doon and Loch Dee may prove to be of regional significance. The strongest evidence for local Mesolithic disturbance came from Loch Dee. The results from the small-basin sites were contrasted with those previously recorded from larger mires and loch sediments.