Your search found 4 records
1 Ahmad, Mobin-ud-Din; Magagula, Thulani F.; Love, D.; Kongo, V.; Mul, M. L.; Kinoti, Jeniffer. 2005. Estimating actual evapotranspiration through remote sensing techniques to improve agricultural water management: A case study in the transboundary Olifants Catchment in the Limpopo Basin, South Africa. In 6th WaterNet/WARFSA/GWP Annual Symposium, Ezulwini, Swaziland, 1-4 November 2005.Theme 5: Water use in irrigated agriculture, challenges and opportunities in Southern Africa. 21p.
Evapotranspiration ; Remote sensing ; Models ; River basins ; Water allocation ; Irrigated farming / South Africa / Limpopo Basin / Olifants Catchment / Mpumalanga Province / Chókwè District
(Location: IWMI HQ Call no: 551.572 G178 AHM Record No: H040786)
This paper describes a case study that uses a remote sensing technique, the Surface Energy Balance Algorithm for Land (SEBAL) to assess actual evapotranspiration across a range of land uses in the middle part of the Olifants Basin in South Africa.. SEBAL enables the estimation of pixel scale ETa using red, near infrared and thermal bands from satellite sensors supported by ground-based measurements of wind speed, humidity, solar radiation and air temperature. The Olifants River system, although supplying downstream users in Mpumalanga Province (South Africa) and Chókwè District (Mozambique), is over-committed, principally for irrigation, in the upper reaches. herefore, quantification of evapotranspiration from irrigated lands is very useful to monitor respect of compliance in water allocations and sharing of benefits among different users. A Landsat7 ETM+ image, path 170 row 077, was acquired on 7 January 2002, during the rainy season and was used for this analysis. The target area contains diverse land uses, including rainfed agriculture, irrigated agriculture (centre pivot, sprinkler and drip irrigation systems), orchards and rangelands. Commercial farming rainfed and irrigated agriculture) is one of the main economic activities in the area. SEBAL ETa estimates vary from 0 to 10 mm/day over the image. Lowest ETa was observed for barren/fallow fields and highest for open water bodies. ETa for vegetative areas ranges 3 to 9 mm/day but irrigated areas, using central pivot, drip and sprinkler systems, appear to evaporate with a higher rate: 6 and 9 mm/day. Penman-Monteith reference crop evapotranspiration ET0 on the same day was found to be 7 mm/day. This indicates that these irrigated areas have no water stress and potential yields can be achieved provided there is no nutrient deficiency. The major finding is that SEBAL results showed that 24% of ETa is from agricultural use, compared to 75% from nonagricultural land use classes(predominantly forest) and only 1% from water bodies. Although irrigation accounts for roughly half of diverted streamflow in the basin, it contributes only about 4% of basin-scale daily ETa at the time of assessment.
2 Institute of Water and Sanitation Development (IWSD). 2010. 11th WaterNet/WARFSA/GWP-SA Symposium, Victoria Falls, Zimbabwe, 27-29 October 2010. IWRM for national and regional integration: where science, policy and practice meet: water for people. Harare, Zimbabwe: Institute of Water and Sanitation Development (IWSD). 763p.
Wastewater treatment ; Filters ; Water quality ; Monitoring ; Water supply ; Sanitation ; Rural areas ; Households ; Drinking water ; Waterborne diseases ; Diarrhoea ; Cholera ; Poverty ; Public health ; Health hazards ; Groundwater ; Climate change ; Water harvesting / Africa / Malawi / Zimbabwe / Uganda / Tanzania / Rwanda / South Africa / Lesotho / Swaziland / Ghana / Nigeria / Gihira Water Treatment Plant / Mutshedzi Water Treatment Plant / Kwazulu-Natal Province / Ugu District / Chegutu District / Mpumalanga Province / Dar es Salaam / Temeke / Lilongwe / Maputo / Accra / Katsina State / Blantyre City / Chilobwe / Chatha
(Location: IWMI HQ Call no: e-copy only Record No: H043409)
http://www.waternetonline.ihe.nl/11thSymposium/WaterSupplyandSanitationFullPapers2010.pdf
https://vlibrary.iwmi.org/pdf/H043409.pdf
https://vlibrary.iwmi.org/pdf/H043409.pdf
(16.26 MB) (20.13 MB)
3 Denby, K.; Movik, S.; Mehta, L.; van Koppen, Barbara. 2016. The 'Trickle Down' of IWRM: a case study of local-level realities in the Inkomati Water Management Area, South Africa. Water Alternatives, 9(3):473-492.
Integrated management ; Water resources ; Water management ; Water allocation ; Water governance ; Water availability ; Legal aspects ; Water law ; Land reform ; Farmers ; Decentralization ; Equity ; Catchment areas ; Rivers ; Agriculture ; Case studies / South Africa / Mpumalanga Province / Limpopo Province / Inkomati Water Management Area
(Location: IWMI HQ Call no: e-copy only Record No: H047789)
http://www.water-alternatives.org/index.php/alldoc/articles/vol9/v9issue3/333-a9-3-6/file
https://vlibrary.iwmi.org/pdf/H047789.pdf
https://vlibrary.iwmi.org/pdf/H047789.pdf
(721 KB)
The historical legacy in South Africa of apartheid and the resulting discriminatory policies and power imbalances are critical to understanding how water is managed and allocated, and how people participate in designated water governance structures. The progressive post-apartheid National Water Act (NWA) is the principal legal instrument related to water governance which has broadly embraced the principles of Integrated Water Resources Management (IWRM). This translation of IWRM into the South African context and, in particular, the integration of institutions related to land and water have faced many challenges due to the political nature of water and land reforms, and the tendency of governmental departments to work in silos. The paper explores the dynamics surrounding the implementation of IWRM in the Inkomati Water Management Area, and the degree of integration between the parallel land and water reform processes. It also looks at what these reforms mean to black farmers’ access to water for their sugar cane crops at the regional (basin) and local levels. The empirical material highlights the discrepancies between a progressive IWRM-influenced policy on paper and the actual realities on the ground. The paper argues that the decentralisation and integration aspects of IWRM in South Africa have somewhat failed to take off in the country and what 'integrated' actually entails is unclear. Furthermore, efforts to implement the NWA and IWRM in South Africa have been fraught with challenges in practice, because the progressive policy did not fully recognise the complex historical context, and the underlying inequalities in knowledge, power and resource access.
4 Nhamo, Luxon; Magidi, J.; Dickens, Chris. 2017. Determining wetland spatial extent and seasonal variations of the inundated area using multispectral remote sensing. Water SA, 43(4):543-552. [doi: https://doi.org/10.4314/wsa.v43i4.02]
Wetlands ; Flooding ; Remote sensing ; GIS ; Spatial planning ; Multispectral imagery ; Satellite imagery ; Sustainable development ; Ecosystems ; Dam construction ; Catchment areas / South Africa / Mpumalanga Province / Witbank Dam
(Location: IWMI HQ Call no: e-copy only Record No: H048390)
https://www.ajol.info/index.php/wsa/article/download/162560/152061
https://vlibrary.iwmi.org/pdf/H048390.pdf
https://vlibrary.iwmi.org/pdf/H048390.pdf
(2.58 MB)
Wetlands can only be well managed if their spatial location and extent are accurately documented, which presents a problem as wetland type and morphology are highly variable. Current efforts to delineate wetland extent are varied, resulting in a host of inconsistent and incomparable inventories. This study, done in the Witbank Dam Catchment in Mpumalanga Province of South Africa, explores a remote-sensing technique to delineate wetland extent and assesses the seasonal variations of the inundated area. The objective was to monitor the spatio-temporal changes of wetlands over time through remote sensing and GIS for effective wetland management. Multispectral satellite images, together with a digital elevation model (DEM), were used to delineate wetland extent. The seasonal variations of the inundated area were assessed through an analysis of monthly water indices derived from the normalised difference water index (NDWI). Landsat images and DEM were used to delineate wetland extent and MODIS images were used to assess seasonal variation of the inundated area. A time-series trend analysis on the delineated wetlands shows a declining tendency from 2000 to 2015, which could worsen in the coming few years if no remedial action is taken. Wetland area declined by 19% in the study area over the period under review. An analysis of NDWI indices on the wetland area showed that wetland inundated area is highly variable, exhibiting an increasing variability over time. An overlay of wetland area on cultivated land showed that 21% of the wetland area is subjected to cultivation which is a major contributing factor to wetland degradation.
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