Research Outputs (Geography, Archaeology and Environmental Studies)

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    High and medium resolution satellite imagery to evaluate late holocene human-environment interactions in arid lands: A case study from the Central Sahara.
    (MDPI, 2017-04) Biagetti, S.; Merlo, S.; Adam, E.; Lobo, A.; Conesa, F.C.; Knight, J.; Bekrani, H.; Crema, E.R.; Alcaina-Mateos, J.; Madella, M.
    We present preliminary results of an Earth observation approach for the study of past human occupation and landscape reconstruction in the Central Sahara. This region includes a variety of geomorphological features such as palaeo-oases, dried river beds, alluvial fans and upland plateaux whose geomorphological characteristics, in combination with climate changes, have influenced patterns of human dispersal and sociocultural activities during the late Holocene. In this paper, we discuss the use of medium- and high-resolution remotely sensed data for the mapping of anthropogenic features and paleo- and contemporary hydrology and vegetation. In the absence of field inspection in this inaccessible region, we use different remote sensing methods to first identify and classify archaeological features, and then explore the geomorphological factors that might have influenced their spatial distribution.
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    Issues of water quality in stormwater harvesting
    (Academy of Science of South Africa (ASSAf), 2017-05) Knight, J.
    No abstract available
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    Disjunct perceptions? Climate change threats in two-low lying South African coastal towns.
    (Nicolaus Copernicus University Press, 2016-03) Hoogendoorn, G.; Grant, B.; Fitchett, J.M.
    Coastal towns rely heavily on the quality and expanse of their beaches to attract tourists. Climate is an important tourism determinant, controlling the length and timing of peak arrivals. South African tourism is particularly reliant on these factors. Perceptions of tourists and tourist accommodation establishment regarding climate change threats to tourism are explored for the towns of St Francis Bay and Cape St Francis. Tourism accommodation establishments were predominantly concerned with day-to-day changes in weather, investing in small-scale infrastructural changes to improve the comfort of their guests. By contrast, tourists demonstrated greater concern for the risk of flooding, sea-level rise and the degeneration of the beaches. This reflects concerning disjunctures between perceptions of tourists and accommodation establishments regarding climate change threats. This may portray to tourists insufficient investment in adaptation at accommodation establishments, resulting in decreased tourist visitations in the short-term in favour of destinations perceived as better prepared.
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    Evidence for climate-induced range shift in Brachystegia (miombo) woodland.
    (Academy of Science of South Africa (ASSAf), 2015-07) Pienaar, B.; Thompson, D.I.; Erasmus, B.F.N.; Hill, T.R.; Witkowski, E.T.F.
    Brachystegia spiciformis Benth. is the dominant component of miombo, the sub-tropical woodlands which cover 2.7 million km2 of south-central Africa and which is coincident with the largest regional centre of endemism in Africa. However, pollen records from the genus Brachystegia suggest that miombo has experienced rapid range retraction (∼450 km) from its southernmost distributional limit over the past 6000 years. This abrupt biological response created an isolated (by ∼200 km) and incomparable relict at the trailing population edge in northeast South Africa. These changes in miombo population dynamics may have been triggered by minor natural shifts in temperature and moisture regimes. If so, B. spiciformis is likely to be especially responsive to present and future anthropogenic climate change. This rare situation offers a unique opportunity to investigate climatic determinants of range shift at the trailing edge of a savanna species. A niche modelling approach was used to produce present-day and select future B. spiciformis woodland ecological niche models. In keeping with recent historical range shifts, further ecological niche retraction of between 30.6% and 47.3% of the continuous miombo woodland in Zimbabwe and southern Mozambique is predicted by 2050. Persistence of the existing relict under future climate change is plausible, but range expansion to fragmented refugia in northeast South Africa is unlikely. As Brachystegia woodland and associated biota form crucial socio-economic and biodiversity components of savannas in southern Africa, their predicted further range retraction is of concern.