对用TDR法、中子法和重量法测得的土壤水含量观测值的比较结果表明 ,随着土壤深度和测量时间的变化 ,中子法的平均测定误差为 3.76 % ,TDR法为 3.5 9%。并且这 2种方法的土壤水含量观测值的时空变化和重量法具有相同的趋势。因此 ,用TDR法测定土壤含水量与用中子法是同样可靠的 The results of soil water content measured by TDR, neutron and gravimetric methods showed that the average measured error of neutron method was 3.76% and the TDR method was 3.59 with the change of soil depth and measuring time %. And the spatio-temporal changes and gravimetric methods of soil water content observed by these two methods have the same trend. Therefore, the determination of soil moisture by the TDR method is as reliable as the neutron method