Journal article
Ecological responses to reductions in freshwater supply and quality in South Africa's estuaries: lessons for management and conservation
Journal of Coastal Conservation, Vol.2(2), pp.115-130
1996
Abstract
Fresh water, a fundamental element of all estuarine ecosystems, is South Africa's most limited natural resource. Recent projections indicate that by the year 2020 the country will be utilizing all its exploitable freshwater sources. Steeply increasing demands by a rapidly growing population on this limited commodity have already resulted in a severe reduction of water supplies to natural users such as estuaries - this trend is predicted to increase in the future. Concurrent with excessive water abstraction, poor land husbandry (e.g. soil erosion) in many catchment basins and pollution (e.g. salinization) in return flows have led to a serious deterioration in water quality. In contrast, a review of estuarine responses to varying flow regimes stresses the strong dependence of local systems on riverine fresh water inputs of adequate quantity and quality. Freshwater dependence is i.a. expressed in: flooding events that scour accumulated sediments, riverine nutrient input to drive estuarine phyto- and zooplankton production, axial salinity gradients that increase habitat and species diversity, and maintenance of open tidal inlets that prevent salinity and temperature extremes and facilitate larval exchange, fish migrations and tidal flushing of salt marshes. Thus, estuarine conservation will have to encompass management of rivers and watersheds and play an increasingly political role in decision processes concerning water allocations among 'human' and 'natural' users. © 1996 EUCC.
Details
- Title
- Ecological responses to reductions in freshwater supply and quality in South Africa's estuaries: lessons for management and conservation
- Authors
- Thomas Schlacher (Author) - University of Port University, South AfricaT H Wooldridge (Author) - University of Port University, South Africa
- Publication details
- Journal of Coastal Conservation, Vol.2(2), pp.115-130
- Publisher
- Springer Netherlands
- Date published
- 1996
- DOI
- 10.1007/BF02905197
- ISSN
- 1400-0350
- Organisation Unit
- School of Science and Engineering - Legacy; University of the Sunshine Coast, Queensland; School of Science, Technology and Engineering
- Language
- English
- Record Identifier
- 99449684902621
- Output Type
- Journal article
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