随着膜下滴灌应用年限增加,农田土壤盐碱变化及对作物影响引起关注。通过在新疆石河子121团,选择地块相近连续应用膜下滴灌2-14 a棉田8块进行盐分变化监测。结果初步表明,膜内0-20 cm土壤脱盐;40-80 cm积盐;膜间裸地盐分表聚,60 cm以上积盐,100 cm以下与膜内土壤盐分接近。滴灌4 a以内盐分含量较高,滴灌6 a以上较低。生育期末0-40 cm土壤盐分随滴灌年限增加而降低;60-100 cm以滴灌4 a积盐最高。滴灌8 a以上棉花成活率较高、株高和单株铃数相差不大。棉花产量以滴灌8 a地块最高,滴灌8 a以内随滴灌年限增加产量增加,滴灌8 a以上随滴灌年限增加产量降低。建议滴灌6 a以内农田加大盐分调控力度,滴灌8 a以上要对土壤盐分进行综合调控。
With the increase in the drip irrigation application years under-mulch drip irrigation,the soil salinization and its influence on the crops call people's attention.The results show that : the soil of inner mulch with 0-20cm soil desalts,from40cm to 80cm accumulates salt;between the mulch bare land the soil salinity on the surface assembles,above the 60cm the soil salinity accumulates,below the 100cm the soil salinity is close to the inner mulch.The soil salinity content within four drip irrigation years is relatively high,it is comparatively low over 6 drip irrigation years.From 0 to 40cm the soil salinity content decreases as the drip irrigation years increases at the end of the growth process;from 60 to 100cm the accumulated salinity with the drip irrigation four years is the highest.The survival rate of cotton is relatively high,the plant height and the single number of bolls are close to each other.The yield is the highest with drip irrigation 8 years,within 8 drip irrigation years the yield increases as the drip irrigation years increase,but over 8 drip irrigation years its yield decreases as the drip irrigation years increase.We suggest enlarging the salinity regulation dynamics within 6 drip irrigation years,over 8 drip irrigation years regulating the soil salinity comprehensively.