Mediterranean-type ecosystems are amongst the most vulnerable to global change. Threats from desertification are projected due to rapid expansion of adjacent semiarid systems. Changes in fire frequency and intensity can alter ecosystem composition and structure, and potentially facilitate transitions between alternative stable states. Given the outstanding biodiversity of the Mediterranean-type fynbos biome in the Greater Cape Floristic Region (GCFR) of South Africa, understanding of the longterm impacts of global change are particularly important. In this study, palaeoecological data are used to assess the effects of changes in climate, fire and land use on vegetation at the semi-arid and temperate margins of the fynbos biome. Previous palaeoecological studies have shown stable fynbos during the recent geologic past, which restricts interpretation of the long-term ecological processes that determine biome resilience. This study sourced sediment cores directly from presentday fynbos-succulent karoo (semi-arid) and fynbos-afrotemperate forest biome boundaries to emphasise ecological dynamics. Fossil pollen, spores and charcoal were extracted from radiocarbon dated sediment cores to provide proxies for vegetation, hydrology, large herbivore abundance and fire. Constrained hierarchical clustering (CONISS), optimal sequence splitting by least-squares, and Non-metric Multidimensional Scaling (NMDS) was applied to the fossil data to identify distinct assemblages in the record, and to further elucidate ecosystem trajectories through time. At the semi-arid boundary at Groenkloof (5,500 cal yrs BP - near present), decreased moisture and fire from 4,000-735 cal yrs BP allowed colonisation of fynbos by a possible 'no-analogue' community dominated by Asteraceae and Poaceae. From 735 cal yrs BP however, climatic amelioration allowed fynbos to re-establish. The system can therefore be viewed as resilient through a capacity for 'recovery' and persistence through turnover in internal composition of fynbos taxa. This sensitive response to climatic forcing reflects the dominant influence of physiological stress at the semiarid limits of Mediterranean-type ecosystems, as well as a Gleasonian type community composition with loose species associations. In contrast, ecosystem

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Over 250 samples were collected over three field seasons from the SE Oman Mountains. Fortyone species of planktonic Foraminifera (belonging to 7 genera) and twenty-eight species of larger benthonic Foraminifera, (belonging to 13 genera) are figured (both by SEM and optical photography) from the Wadi Musawa and Wadi Suq sections. Nine planktonic foraminiferal zones are formally recognised between the Upper Palaeocene(P 4) and upper Middle Eocene (P14). The known stratigraphic distribution of these species was used to recognise the zones P 5, P8-P9 as equivalentt o standard zones of Blow, 1969,1979, whilst strata considered generally equivalent to P4 and PIO-PI4 in the Wadi Musawa section are zoned on the basis of the local range. Younger sediments can only be dated on larger Foraminifera. A possible hiatus representing the planktonic zones P 6/P7 is tentatively identified. Fifteen lithostratigraphic units are recognised and formally described from three formations: the Abat Formation( units A-D), the Musawa Formation (units E-L) and the Tahwah Formation (units M-0). The ages of the Abat and Musawa formations are redefined and are shown to be significantly older than previously published. Biostratigraphical and palaeoenvironmental data from both the planktonic and the larger Foraminifera has been used in conjuction with the lithostratigraphy to construct a sequence stratigraphy, in which several cycles have been recognised. Some of these cycles may correlate with the global sea-level cycles of Haq et al. (1987) and include TA2.3 and TAM, Whilst others are local due to tectonically induced regressive and transgressive events. Information not only from the Foraminifera but also from radiolaria, ostracods and molluscs has been used to reconstruct the palaeoenvironment for the Omani Palaeogene. Parts of the Lower and Middle Eocene contain in-situ larger Foraminifera indicating deposition in a shelf (dominantly mid to outer) setting. During the late Palaeocene, most of the early Eocene, part of the middle Eocene, and the entire late Eocene/early Oligocene mixed assemblages of planktonics and shallow water benthonics were the dominant Foraminifera. The occurrence of the these two assemblages in deepwater sediments indicates a substantial period of time in which penecontemporaneous uplift and resedimentation of carbonate shelf deposits into deeperwater occurred. A number of new larger and smaller benthonic Foraminifera are described and one planktonic foraminifer renamed.

The lower Kennet Valley terraces reflect fluctuations in river regime through the Quaternary. Sediments and valley floor geomorphology provide a detailed record of Devensian and Flandrian fluvial behaviour and environmental change. Two major surfaces occur, the floodplain and the Beenham Grange Terrace (2 - 3m above the floodplain). Levelling showed that the terrace south of the river, underlain by deposits of two Early Devensian interstadials, was part of the Beenham Grange level, and not the Thatcham Terrace as previously proposed. The fluvial succession consisted of the subflood plain Midgham Peat Formation overlying the Woolhalllpton Gravel Formation The latter also rises to form the surface of the Beenham Grange Terrace adjacent to the floodplain. A subunit of the Woolhampton Formation, the Heales Lock Gravel Member, thickened over a large depression in the local Tertiary bedrock and was associated with syndepositional subsidence which aided excellent subfossil preservation in the sediments. A major channel fill within the member - the Wasing Sand Bed - contained Betula with a distinctive herb flora which, with 14C data, indicates a correlation with the Late Devensian Windermere Interstadial. Lithostratigraphy, biostratigraphy and 14C data from gravels resting unconformably on the Wasing Sand indicated a Loch Lomond Stadial age. The sedimentology of the Midgham Peat Formation reflected early Flandrian reductions in flow competence associated with silt, peat and tufa deposition. Regional woodland expansion was followed by alder can' closing of the floodplain during the Atlantic. A subsequent hiatus ended ,with Sub-boreal (?Bronze Age) flooding and deposition, perhaps anthropogenically induced. An upper silt reflects lower energy flooding in an agricultural landscape. To avoid taphonomic difficulties macrofossil interpretations utilised only well-preserved material. Pollen taphonomy was more problematic. A pilot study in subarctic Canada suggested that, while fluvial pollen assemblages were not exactly equivalent to regional pollen rain through local inputs and sorting, vegetation changes were identifiable.

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Small mammals have often been utilised as indicators of past environments. Before palaeoecological assessments can be made, investigations into the origin and mode of deposition are carried out. Many small mammal accumulations are predator-derived, and in order to take account of predatory bias in these deposits, it is necessary to identify the predator. Several methodologies have catalogued patterns of bone modification from dietary waste of modern predators, for comparison with taphonomic features found on archaeological assemblages of small mammals. The majority of this research has concentrated only on the adult age range from these predators. However, data from owls have shown that younger individuals are often responsible for more extensive bone modification. To investigate this difference associated with the age of predators and bone modification, two modern Tyto alba roost samples and three modern Tyto alba nest samples were analysed to provide evidence of bone modification from adult and baby owls. Significant differences were found between these two groups, with higher rates of bone digestion associated with the nest samples, To test whether these taphonomic patterns could be identified in archaeological deposits, small mammal assemblages from four archaeological sites (The Old Vicarage at Tadcaster, Filey Roman Signal Station, Fox Hole Cave and Carsington Pasture Cave) were analysed. At one of these sites, bone digestion matched that of the Tyto alba nest sites. Bone digestion at the other three sites was higher than that recorded in this study for either Tyto alba adults or their young. This study has shown that it is possible to recognise owl nests in the archaeological record, and concludes that analysis of these assemblages can elucidate not only the origin of specific predator deposits, but can also be used to investigate the nature of human occupation, usage and abandonment of these sites.

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