Simulation of soil water movement and deep drainage from jujube tree orchard in arid areas

摘要

In arid areas, water is especially critical for residential, industrial, and agricultural users since the water resources are limited. Consequently, how to increase irrigation efficiency is of high concern to the local agricultural authorities. In arid areas like Aksu in Xijiang Province, China, agricultural irrigation is one of the most important factors which impacts on the water content and also infiltration in the subsurface. For Jujube, the intensity and frequency of irrigation greatly influence the infiltration, which may cause excessive irrigation. As well known, the movement of water during irrigation must be recognized in order to properly evaluate current irrigation patterns and take measures to increase irrigation efficiency and reduce water losses due to evaporation and infiltration In this paper, the code, HYDRUS-1D, which can simulate water, heat, and/or solute movement in one-dimensional, variably-saturated porous media, was used to evaluate the movement of water and the characteristics of infiltration in sandy soil. The infiltration rate during irrigation is very large under traditional border irrigation conditions with a rate of 1124.0 mm/year, which accounts for 60% of the total irrigation water. Therefore, it is not suitable to adopt border irrigation if we plan to reduce infiltration and improve irrigation efficiency. Simulation suggests that furrow irrigation or micro-irrigation technologies which use high frequency and small-ration irrigation methods be used in the arid areas.