Show simple item record

dc.contributor.authorDe Winnaar, Gary.
dc.date.accessioned2010-09-09T09:34:04Z
dc.date.available2010-09-09T09:34:04Z
dc.date.created2009
dc.date.issued2009
dc.identifier.urihttp://hdl.handle.net/10413/1033
dc.descriptionThesis (M.Sc.) - University of KwaZulu-Natal, Pietermaritzburg, 2009.en_US
dc.description.abstractWater scarce countries such as South Africa are subject to various hydrological constraints, particularly within resource poor farming communities that are reliant on rainfed agriculture. Recent initiatives to address this issue have shifted focus to explore more efficient alternatives to water supply. Adoption of water system innovations through the use of runoff harvesting is one such alternative that provides a means to supplement water use for increased food production. However, increasing the implementation of runoff harvesting, without encountering unintended impacts on downstream hydrological and ecological systems, requires better understanding of the hydrologic and environmental impacts at catchment scale. The objective of this dissertation was to gain knowledge to the ecohydrological impacts that are likely to occur with the adoption of water system innovations as a means for upgrading rainfed smallholder farming systems. To fulfil this objective, a research component was developed whereby tools were utilised to facilitate this process on the basis of two broad aims. The first aim entailed developing a method for locating areas that are most suitable for the adoption of runoff harvesting using Geographical Information Systems (GIS). This was achieved by spatially modelling physical properties of the landscape which influence runoff response. Combining potential runoff with socio-economic factors produced a runoff harvesting map of sites with low, medium and high suitability. This is illustrated by a case study at the Potshini catchment, a small sub-catchment in the Thukela River basin, South Africa. The second aim involved modelling the impacts that runoff harvesting would have on the downstream hydrology and ecology based on the alteration of the flow regimes. To accomplish this, the ACRU Agrohydrological model which was configured to represent runoff harvesting, was used to simulate streamflow for quaternary catchments within the headwaters of the Thukela River basin. Simulated streamflows from ACRU was input into the IHA model to generate ecologically relevant hydrological parameters. Alteration of the flow regime due to runoff harvesting was mostly a reduction in high and low flows however the impacts were insignificant. This suggests that, depending on the intensity of runoff harvesting, downstream ecological impacts are insignificant.en_US
dc.language.isoenen_US
dc.subjectEcohydrology--KwaZulu-Natal--Tugela river basin.en_US
dc.subjectWater harvesting--KwaZulu-Natal--Tugela river basin.en_US
dc.subjectSustainable agriculture--KwaZulu-Natal--Tugela river basin.en_US
dc.subjectRunoff irrigation--KwaZulu-Natal--Tugela river basin.en_US
dc.subjectRunoff--KwaZulu-Natal--Tugela river basin.en_US
dc.subjectTheses--Bioresources engineering and environmental hydrology.en_US
dc.titleTools to assess the ecohydrological impacts of water system innovationsen_US
dc.typeThesisen_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record