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一、旱作农田的分布和土壤肥力状况榆次县的旱作农田主要分布在县境东、北部的丘陵坡地和沟谷山坡,海拔850-1,300米,总面积26.34万亩,占全县耕地的58.1％。该区年降水量430毫米左右,年平均气温8-9℃,无霜期135-150天,≥10℃的积温3,300-3,500℃,具有冬春干旱、夏秋多雨、光照充足、蒸发量大的气候特点。根据1981-1982年土壤普查,旱作农田土壤干筛团粒为40-65％,平均51.4％;水稳性团粒为6.6-16.4％,平均11％;土壤容重1.01-1.36,平均1.14;孔隙度为61.9-48.7％,平均57％。土壤养分含量:有机
First, the distribution of dry farmland and soil fertility conditions Yuci County, dry farmland are mainly distributed in the county east and north of the hill slopes and valleys slopes, elevation 850-1,300 meters, with a total area of 26.34 hectares, accounting for the county’s arable land 58.1%. The annual rainfall of about 430 mm, the annual average temperature of 8-9 ℃, frost-free period 135-150 days, ≥ 10 ℃ accumulated temperature 3,300-3,500 ℃, with winter and spring drought, summer and rainy, adequate light, large evaporation climate characteristics . According to the 1981-1982 soil census, the soil dry-sieved aggregates of dry farmland was 40-65% with an average of 51.4%; the water-stable aggregates were 6.6-16.4% with an average of 11%; the soil bulk density was 1.01-1.36 with an average of 1.14; 61.9-48.7%, with an average of 57%. Soil nutrient content: organic