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一、运城地区土壤盐分运行规律一是早春稳定期,时间是头年的12月至第二年2月。此时天气寒冷气温低,地面蒸发很小,土壤水分处于冻结缓慢运行状态,土壤盐分处于稳定期,这三个月期间0—30厘米土层中盐分含量平均在0.46——0.64％范围,变幅很小,基本稳定。二是春季返盐期,时间在3—5月份,此时土壤解冻,春季多风,土壤水分蒸发很快,盐分随水分上升迅速积于地表,0—30厘米土层含盐量由2月份的0.61％到3月底增加到1％,0—5厘米土层含盐量最高达2.45％。三是夏季积盐高峰期,时间在6—7月份,0—30厘米土层含盐量由0.78％增加到1.16％,0—5厘米土层积盐最高达4.26％。四是夏末秋初脱盐期,时间在7—9月份,这三个月降水量占全年的50％,土壤盐分在雨水的作用下被淋浴洗去,土层含盐量0—30厘米降为0.61％,0—5厘米降至0.73％。五是秋末冬初返盐期,时间在10—11月份。这时雨量相对减
First, the law of soil salinity in Yuncheng First, the stability of early spring, the first year of December to the second year in February. At this time the cold weather temperature is low, the ground evaporation is very small, the soil moisture in a slow freeze operation, soil salinity in a stable period, the salt content of 0-30 cm soil layer during the three-month average of 0.46--0.64% range, variable A small, basically stable. Second, the spring back to the salt period, the time in March-May, when the soil thaw, windy spring, the soil moisture evaporates quickly, the salt rapidly increases with the moisture accumulation in the surface, 0-30 cm soil salt content from February Of the 0.61% to the end of March increased to 1%, 0-5 cm soil salt content up to 2.45%. The third is summer peak salt accumulation, time in June-July, 0-30 cm soil salt content increased from 0.78% to 1.16%, 0-5 cm soil salt up to 4.26%. Fourth, early summer and early autumn desalination period, the time in July-September, the three-month precipitation accounted for 50% of the year, soil salinity washed by the shower under the action of the rain, the soil salt content of 0-30 cm Down to 0.61%, 0-5 cm down to 0.73%. Fifth, early fall winter return salt period, the time in 10-11 months. At this time the relative reduction of rainfall