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1983年至1984年18个月在兰州皋兰县定点取样,烘干测定的砂田土壤的水分含量数据,并与同期以同样方法测定的一般土田土壤的含水量进行了比较,砂田土壤的水分特征:(1)平均含水量 砂田土壤比一般土壤高出2%左右;(2)逐层比较 砂田土壤耕作层(0—20cm)的含水量与一般土壤表层含水量之差异最大,往下差异逐层减小;(3)季节变化 砂田土壤水分含量的最大值出现于6月,7月中旬以后急剧下降,而一般土壤的高峰出现在5月,6月中旬以后急减,即砂田土壤水分滞后一个月。
From 1983 to 1984, 18 months in Gaolan County, Lanzhou, fixed-point sampling, drying measured sand field soil moisture content data and compared with the same method measured in the same soil water content of general soil, sandy soil moisture characteristics : (1) The average soil water content is about 2% higher in sandy soil than in normal soil; (2) The difference between the water content of soil layer (0-20cm) and that of soil layer (3) The maximum value of seasonal soil moisture content in sandland appeared in June and dropped sharply after mid-July, while the peak of general soil appeared in May and dropped sharply after mid-June, that is, the soil moisture of sand field lagged A month