Effects of tillage on runoff from a bare clayey soil on a semi-arid ecotope in the Limpopo Province of South Africa

• Published in: Water S. A. 2011-04, Vol.37 (2), p.165-172
• Main Authors: Van Rensburg, Leon D., Mzezewa, Jestinos
• Format: Article
• Language: English
• Subjects: Agricultural land; Biological and medical sciences; Coefficients; Crop production; Crop yield; Crops; Earth sciences; Earth, ocean, space; Evaporation; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Harnesses; Hydrology; Hydrology. Hydrogeology; Limpopo Province; No-tillage; Rain; Rainfall; Rainfall simulation; Rainfall-runoff relationships; Rainwater harvesting; Runoff; Runoff coefficient; Simulated rainfall; Simulation; Small farms; Soil (material); Soil management; Soils; Studies; Tillage; University of the Free State; University of Venda; Water harvesting; Water loss; Water requirements
• ISSN: 0378-4738; 0378-4738
• DOI: 10.4314/wsa.v37i2.65862

Runoff constitutes one of the major water losses from agricultural fields in semi-arid areas. However, by adopting appropriate soil management practices, the runoff can be harnessed for improving crop yields. The main objective of this study was to quantify rainfall-runoff relationships under in-field rainwater harvesting (IRWH) using simulated rainfall, and to compare these results to those obtained with annually tilled conventional tillage (CON) (control). IRWH is a special type of no-till (NT) crop production practice that promotes runoff from a crusted runoff strip into basins where the water infiltrates beyond evaporation but is available for crop use. Runoff was related to time to runoff, total runoff, final runoff rate and runoff coefficient. This experiment demonstrated that by adopting IRWH production technique smallholder farmers could harness an additional 45.54 m3·ha-1 of water compared to the CON system. The extra water harvested could meet about 1% of maize water requirements.