冬小麦田咸水灌溉与土壤盐分调控试验

EXPERIMENTS ON IRRIGATION WITH BRACKISH GROUNDWATER AND MANAGEMENT OF SOIL SALT IN WINTER WHEAT FIELDS

利用浅层咸水灌溉 ,可使浅层咸水分布区无效降水转化为有效水资源 ,缓解北方水资源紧缺的矛盾 ;通过王瞳试验场进行的咸水灌溉与土壤盐分调控试验表明 ,利用 3g/L左右的微咸水连续灌溉 5 a,根层土壤溶液浓度未超过小麦的耐盐能力 ,且作物增产 ;多年盐分变化趋势为 :1994～ 1997年 1m深度内土壤总含盐量在一定范围内波动 ,总体变化不大 ,连续干旱的 1997～1998年略呈上升趋势 ;麦秸覆盖和施有机肥能减少根层土壤盐分 ,对土壤盐分具有有利的调控作用 ,具有增产效果。

Irrigation with brackish groundwater can promote the transform of precipitation into available water resources in area of shallow saline water and relax water shortage in Northern China.As a case study of brackish groundwater irrigation in arid and semi arid areas, experiments in Wangtong experimetal area are discussed in detail. After continuous 5 years' irrigation by brackish groundwater (TDS of 3-4 g/L) in Wangtong experiment area, the salt accumulated in the soil does not go beyond the crop salt tolerance and the crop yield has increased. The balance of soil salinity is maintained during 1994-1997, but soil salinity tends to rise in 1997-1998 because of little rainfall in 1997. While wheat straw mulching and fertilization treatment can decrease soil salinity in root zone and increase crop yields,which may favour the beneficial to management of soil salt while irrigation by brackish groundwater.