Evaluating The Potential Contribution Of Episodic Toxicity Data To Environmental Water Quality Management In South Africa
- Authors: Gordon, Andrew K , Mantel, Sukhmani K , Muller, Nikite W J
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/438310 , vital:73450 , ISBN 978-1-4312-0070-2 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/KV259-10.pdf
- Description: An important aspect of the dynamics of nutrients and pollutants in natural systems is captured in the concept of allochthony, founded on the observation that nutrients and energy in a variety of forms are transferred between adjacent habitats, com-munities and ecosystems that are not routinely considered as connected. Different forms of nutrients and energy move across the conceptual boundaries of habitats via organisms’ activities or physical processes such as wind or water currents, and these transfers can represent important food subsidies. Such cross-partition ecolog-ical subsidies can augment the nutritional condition, biomass and biodiversity of communities, particularly where local production (or autochthony) alone may be inadequate to support local food webs. Furthermore, organic subsidies can influ-ence population dynamics, community interactions and ecosystem processes, and can represent dominant flux inputs in ecosystem budgets. Our intention was to explore organic nutrient fluxes in relation to a primarily lotic (i.e. flowing) aquatic sys-tem at the scale of a hydrological catchment.
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- Date Issued: 2011
Incorporating uncertainty in water resources simulation and assessment tools in South Africa
- Authors: Hughes, Denis A , Kapangaziwiri, E , Mallory, S J , Wagener, T , Smithers, J
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/438239 , vital:73445 , ISBN 978-1-4312-0128-0 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/18381.pdf
- Description: The main objective of the project was to contribute to the incorporation of uncer-tainty assessments in water resource decision making in South Africa, thereby quan-tifying the risks associated with specific decisions about planned future water re-source developments. This objective was supported by several specific aims: 1. De-velop an understanding of uncertainty and associated risks in water resource man-agement on the basis of literature and known practices, nationally and internation-ally. 2. Identify and characterise the main sources of uncertainty (focusing on cur-rent South African practice and typical situations of data availability). 3. Develop techniques and guidelines for quantifying the uncertainty associated with different models. This will include uncertainty in all relevant areas (hydrological, climate, economic, social, etc.). 4. Determine the effects of uncertainty on water resource management and identify what level of uncertainty is acceptable. 5. Develop guide-lines for the communication of uncertainty and the impacts to various stakeholder groups involved within water resource planning and management. This aim will need to address the issue of the links between uncertainty and risk. 6. Develop guidelines for incorporating uncertainty and the associated risk into water resource decision making processes. 7. Identify those areas of uncertainty that can be realistically re-duced and which will have the greatest impact on reducing the risks involved with water resource decision making.
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- Date Issued: 2011