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分析黄土丘陵区枣林土壤水分时间稳定性特征可保证土壤水分监测和预报的精确度,同时为优化枣林灌溉措施及生态环境建设提供帮助.利用累积概率分布、相对偏差和spearman秩相关系数等方法,研究黄土丘陵区枣林土壤水分时间稳定性特征.结果表明,0～10cm和10 ～30cm土层下土壤含水量与变异系数(CV)间均呈现出显著递减的指数函数关系(y =0.4932e-0.1116x,R2 =0.9521),且基本表现出中等变异.随着测定时段的变化,研究区土壤水分空间分布格局呈现出一定的时间稳定性特征.10 ～30cm土壤含水量时间稳定性较0～ 10cm好,其平均相对偏差(MRD)变化范围为-21.32％～34.23％,MRD的标准偏差(SDRD)变化范围为6.02％ ～47.58％.通过时间稳定性特征分析可以确定区域土壤水分均值的代表性测点(点18),该代表性测点土壤含水量和区域水分均值相关性高、误差小(R2＞ 0.98,RMSE ＜0.8).研究区0～30cm土壤含水量spearman秩相关系数较低,其值小于0.72,不同时段下土壤含水量大部分都表现出显著或极显著正相关关系.“,”Temporal stability of soil moisture in loess hilly region could ensure the accuracy of soil moisture monitoring and prediction,and help optimize the irrigation practices of jujube orchard and ecological environment construction.The methods of cumulative frequency,mean relative difference and spearman rank correlation coefficient were used to research temporal stability of soil water on jujube orchard.The results showed that soil water content at 0 ～ 10cm and 10 ～ 30cm depths had moderate variability.The soil water content displayed significant decreasing exponential function relation with coefficient of variation (y =0.4932e-0.1116x,R2 =0.9521).The spatial distribution pattern of soil moisture had a certain characteristic of temporal stability with the determination of date.Temporal stability of soil moisture at 10 ～ 30cm layer was better than 0 ～ 10cm layer.The mean relative difference(MRD) of soil moisture at 10 ～ 30cm layer ranged from-21.32％ to 34.23％,and its standard deviation (SDRD) ranged from 6.02％ to 47.58％.The representative sites of mean soil moisture in studied area could be determined (site 18) based on temporal stability of soil moisture,and there was a higher correlation and lower error (R2 ＞ 0.98,RMSE ＜ 0.8) for mean soil moisture between representative sites and study area.The spearman rank correlation coefficients were less than 0.72 indicated low values,and the soil water contents at different dates mostly showed significant or extremely significant positive correlation in study area.