DSpace
 

Researchspace >
General science, engineering & technology >
General science, engineering & technology >
General science, engineering & technology >

Please use this identifier to cite or link to this item: http://hdl.handle.net/10204/5393

Title: Total evaporation estimates from a Renosterveld and dryland wheat/fallow surface at the Voëlvlei Nature Reserve (South Africa)
Authors: Jovanovic, NZ
Jarmain, C
De Clercq, WP
Vermeulen, T
Fey, MV
Keywords: Evapotranspiration
Large aperture scintillometer
Renosterveld
Soil water balance
Surface energy balance algorithm for land
SEBAL
Wheat
Fallow systems
Drylands
Voëlvlei nature reserve
Issue Date: Oct-2011
Publisher: Water Research Commission
Citation: Jovanovic, NZ, Jarmain, C, De Clercq, WP 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 471-482
Series/Report no.: Workflow request;7715
Abstract: 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.
Description: Copyright: 2011 Water Research Commission
URI: http://www.ajol.info/index.php/wsa/article/viewFile/71424/60371
http://hdl.handle.net/10204/5393
ISSN: 0378-4738
Appears in Collections:Ecosystems processes & dynamics
General science, engineering & technology

Files in This Item:

File Description SizeFormat
Jovanovic_2011.pdf811.6 kBAdobe PDFView/Open
View Statistics

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

 

Valid XHTML 1.0! DSpace Software Copyright © 2002-2010  Duraspace - Feedback