The Research on Temporal and Spatial Distribution Characteristic of Soil Water Content of Pear Orchard

Based on gridding sampling,soil water was conducted with Trime measuring system in pear orchard of Yantai Academy of Agricultural Sciences from April to August in 2005,and the soil water statistic characteristic,semivariance,fractal dimension and the law of temporal and spatial distribution were also studied.The result showed that the soil water had obviously spatial variability,and the coefficients of variation were 0.0889,0.2479,0.1291 and 0.2191,respectively.Furthermore the ranges were 27.25,4.25,9.73 and 5.32 m,and fractal dimensions were 1.842,1.957,1.926 and 1.929.The coefficient of variation and fractal dimension of soil water measured after rainfall were the least,at the same time range was the largest,which showed that rainfall maked spatial dependence of soil water more obvious and its distribution more even,but the succedent evaporation of soil maked them opposite.