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１９９０～１９９３年乐都马营旱作区农田土壤水分定位观测资料表明，中位山旱区农田土层深厚且孔隙度较大，年均蓄水量高于低位区和高位区。作物对低位区农田深层水分利用量多于中位区和高位区，０～２００ｃｍ土壤水分变率在低位区表现强烈。在各山旱区农田土壤水分耗散量最高峰值时间通常在作物生长最旺盛期和温度高峰期的７月下旬到８月上旬。应用水分平衡法研究了作物耗水量，丰水年耗水基本来自自然降水，歉水年耗水由自然降水和土壤水分补给构成，年际间同一作物耗水量各异
From 1990 to 1993, the data of soil moisture of farmland in Lupu maying dry farmland show that the soil of middle dry land farmland is deep and rich in porosity, and the average annual water storage is higher than the low and high areas. The deeper water use of crops in the lowland was lower than that of the middle and highland, and the soil moisture variability of 0 ~ 200cm was strong in the lowland. The peak time of soil moisture dissipation in farmland in each mountainous and dry area is usually between late July and early August in the peak crop growth and temperature peak. The water consumption of crops was studied by using water balance method. The water consumption in wet years basically came from natural precipitation. The water consumption in apricot years was composed of natural precipitation and soil moisture supply. The water consumption of the same crop varied in different years