Forecasting on Deep Soil Water of Cherry Orchard of Jiaodong Based on Surface Soil Water Information

In the bloom growth stage of the cherry tree,Trime soil water system was used to measure soil water of cherry orchard and the curve between soil water and soil depth and models is founded using surface soil water to forecast deep soil water.The results showed that the variance of 0～90 cm soil water was more evident,and the variance coefficient of below 0～90 cm decreased obviously.Furthermore the corresponding effects of various layers less than 50 cm and more than 50 cm deep soil water were better except for one or two experience expressions,and the relative error of results were less than 4.7%. The relative error of results less than 1% and between 1% and 3% accounted for 34.7% and 55.6% respectively,which were obviously less than the relative error of results of other layers less than 50 cm,when the deep soil water was forecasted with 0～50 cm soil water.As a result,the various layers less than 0～50 cm could be to forecast better deep soil water in this region,but the forecasting precision of 0～50 cm layer was the best.