Jovanovic, NebojsaJarmain, CDe Clercq, WPVermeulen, TFey, MV2011-12-132011-12-132011-10Jovanovic, N., Jarmain, C., De Clercq, W.P. et al. 2011. Total evaporation estimates from a Renosterveld and dryland wheat/fallow surface at the Voëlvlei Nature Reserve (South Africa), Water SA, Vol 37(4), pp 471-4820378-4738http://www.ajol.info/index.php/wsa/article/viewFile/71424/60371http://hdl.handle.net/10204/5393Copyright: 2011 Water Research CommissionAccurate quantification of the water balance, in particular evapotranspiration, is fundamental in managing water resources, especially in semi-arid areas. The objective of this study was to compare evaporation from endemic vegetation in the Renosterveld and a dryland wheat/fallow cropping system. The study was carried out in the mid-reaches of the Berg River catchment (South Africa), characterised by dryland salinity. Measurements of total evaporation from these 2 land uses were carried out with large aperture scintillometers during window periods from 2005 to 2007. Total evaporation was measured to be higher in Renosterveld than in wheat during the rainy winter season. In the dry summer season, total evaporation from Renosterveld was limited by soil water supply, and vegetation was under water stress. Spatial variability of total evaporation from both wheat/fallow land and Renosterveld was estimated using the Surface Energy Balance Algorithm for Land (SEBAL) model for 3 climatically different years. The scintillometer measurements were used to determine basal crop coefficients for long-term (20 years) simulations with the HYDRUS-1D model to assess temporal variability in total evaporation. Long-term simulations indicated that well-established, deep-rooted Renosterveld uses 39% more water than the shallowrooted wheat/fallow system. A change in land use from Renosterveld to dryland annual crops could therefore affect the soil water balance, cause shallow saline groundwater tables and degradation of soil and water resources.enEvapotranspirationLarge aperture scintillometerRenosterveldSoil water balanceSurface energy balance algorithm for landSEBALWheatFallow systemsDrylandsVoëlvlei nature reserveArticleJovanovic, N., Jarmain, C., De Clercq, W., Vermeulen, T., & Fey, M. (2011). Total evaporation estimates from a Renosterveld and dryland wheat/fallow surface at the Voëlvlei Nature Reserve (South Africa). http://hdl.handle.net/10204/5393Jovanovic, Nebojsa, C Jarmain, WP De Clercq, T Vermeulen, and MV Fey "Total evaporation estimates from a Renosterveld and dryland wheat/fallow surface at the Voëlvlei Nature Reserve (South Africa)." (2011) http://hdl.handle.net/10204/5393Jovanovic N, Jarmain C, De Clercq W, Vermeulen T, Fey M. Total evaporation estimates from a Renosterveld and dryland wheat/fallow surface at the Voëlvlei Nature Reserve (South Africa). 2011; http://hdl.handle.net/10204/5393.TY - Article AU - Jovanovic, Nebojsa AU - Jarmain, C AU - De Clercq, WP AU - Vermeulen, T AU - Fey, MV AB - Accurate quantification of the water balance, in particular evapotranspiration, is fundamental in managing water resources, especially in semi-arid areas. The objective of this study was to compare evaporation from endemic vegetation in the Renosterveld and a dryland wheat/fallow cropping system. The study was carried out in the mid-reaches of the Berg River catchment (South Africa), characterised by dryland salinity. Measurements of total evaporation from these 2 land uses were carried out with large aperture scintillometers during window periods from 2005 to 2007. Total evaporation was measured to be higher in Renosterveld than in wheat during the rainy winter season. In the dry summer season, total evaporation from Renosterveld was limited by soil water supply, and vegetation was under water stress. Spatial variability of total evaporation from both wheat/fallow land and Renosterveld was estimated using the Surface Energy Balance Algorithm for Land (SEBAL) model for 3 climatically different years. The scintillometer measurements were used to determine basal crop coefficients for long-term (20 years) simulations with the HYDRUS-1D model to assess temporal variability in total evaporation. Long-term simulations indicated that well-established, deep-rooted Renosterveld uses 39% more water than the shallowrooted wheat/fallow system. A change in land use from Renosterveld to dryland annual crops could therefore affect the soil water balance, cause shallow saline groundwater tables and degradation of soil and water resources. DA - 2011-10 DB - ResearchSpace DP - CSIR KW - Evapotranspiration KW - Large aperture scintillometer KW - Renosterveld KW - Soil water balance KW - Surface energy balance algorithm for land KW - SEBAL KW - Wheat KW - Fallow systems KW - Drylands KW - Voëlvlei nature reserve LK - https://researchspace.csir.co.za PY - 2011 SM - 0378-4738 T1 - Total evaporation estimates from a Renosterveld and dryland wheat/fallow surface at the Voëlvlei Nature Reserve (South Africa) TI - Total evaporation estimates from a Renosterveld and dryland wheat/fallow surface at the Voëlvlei Nature Reserve (South Africa) UR - http://hdl.handle.net/10204/5393 ER -