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通过对青海省旱地土壤水分动态变化规律的分析，发现大气降水对裸地土壤水分的影响十分明显，水平和垂直土壤水分梯度均明显大于草地和作物地；天然草地浅层（０－３０ｃｍ）土壤水分明显受天气状况和牧草生长影响。在牧草返青期，浅层土壤水分明显处于低值期，４０－６０ｃｍ土层是土壤水分的高值区，土壤水分不断向浅层输送，可弥补大气降水的不足。在牧草整个生长季节，２０ｃｍ土层的土壤水分处于低值区，４０－６０ｃｍ土层的土壤水分处于高值区，７０－１００ｃｍ土壤水分在牧草的整个生长季保持相对稳定；作物（春小麦）地土壤水分，在小麦生长旺盛的６月份，表现出土壤供水不足。７－８月份降水仅能渗透到土壤浅层（０－２０ｃｍ），在３０ｃｍ深处，土壤湿度仍处于低值区。秋季降水可以入渗到较深层处（３０－４０ｃｍ），秋季降水量对决定次年土壤的底墒起着重要作用。
Through the analysis of the dynamic changes of soil moisture in dryland in Qinghai Province, it is found that the effects of atmospheric precipitation on soil moisture in bare land are obvious, and the horizontal and vertical soil moisture gradients are obviously larger than grass and cropland. In the shallow layer (0-30cm) of natural grassland Moisture is clearly affected by weather conditions and pasture growth. In the forage rejuvenation stage, the shallow soil moisture is obviously at a low level. The 40-60cm soil layer is the high value area of soil moisture, and the soil moisture is continuously transported to the shallow layer, which can make up for the lack of atmospheric precipitation. Soil moisture in the 20 cm soil layer was in the low value area and the soil moisture in the 40-60 cm soil layer was in the high value area throughout the growing season. The soil moisture in the 70-100 cm layer remained relatively stable throughout the growing season of the forage grass. The crop (spring wheat) Soil moisture, which shows a lack of water in the soil during the month of vigorous wheat growth. July-August precipitation can only penetrate shallow soil (0-20cm), at 30cm depth, soil moisture is still in the low value area. Fall precipitation can infiltrate to deeper layers (30-40cm). Autumn precipitation plays an important role in determining the soil moisture content of the following year.