Abstract:
This study estimated spatial variation of reference evapotranspiration (ETo) and its influence on the
hydrology of Luvuvhu River Catchment.The ETo plays a key role in irrigation systems design, water
resource management under irrigated and rainfed production.Simulation of ETo was performed using
the Penman-Monteith method in CROPWAT 8.0 software. Results showed the spatial and temporal
distribution of ETo with peaks in summer months. Areas with higher ETo values were near rivers and
streams, which generally have more abundant vegetation. Areas with low ETo values were relatively
dry, where pasture and grasslands dominated the landscape. Correlation results showed that no
relationship exists between streamflow and ETo (r = 0.36) in the study area, hence, a significant
relationship exists between rainfall and ETo (r = 0.86). The study recommends the use
ofCROPWATmodel for computing ETo under arid and semi-arid climatic conditions for water resource
management and planning.
