Estimation of Evapotranspiration of Citrus Tree from Climate Data for Groundwater Management in Saudi Arabia

Abstract

Water shortage for irrigation is a major problem in many arid and semiarid regions of the world. Saudi Arabia faces similar problem of water shortage for irrigation due to arid climatic conditions coupled with low rainfall and limited groundwater supplies to meet the growing need of water from crop and other field crop irrigation. In Saudi Arabia, citrus is frown as a cover crop in the date palm orchard and needed more water for sustainable fruit production. The main objective of this study was to estimate evapotranspiration of citrus from climatic data for different regions of Saudi Arabia and compare it with the evapotranspiration determined elsewhere for efficient management of citrus trees grown under arid climatic conditions. This study compared four different methods of calculating evapotranspiration (ET) of citrus tree with a standard method for seven different regions of Saudi Arabia. The mean daily estimated ET (mm day-1) of citrus tree came to 1.83-8.66 (Hail), 2.14-8.26 (Kharaj), 2.45-7.23 (Taif), 1.61-7.73 (Qatif), 2.68-8.96 (Madinah), 2.14-8.10 (Hofuf) and 2.96-8.12 (Najran) regions of Saudi Arabia. The results showed definite differences in ET among the regions in Saudi Arabia. Also, ETE values were significantly higher than those found in Arizona, USA. However, among the four methods, Blaney-Criddle gave the highest ET values and the radiation method gave the lowest values. Overall, the study findings provided an excellent potential of using meteorological data for estimating the ET of different fruit trees other than citrus under varying arid climatic regions.