辽西半干旱地区农田水分循环特征的研究 Ⅰ.农田供水状况研究

Characteristics of field water cycling in semiarid area of western Liaoning Ⅰ.Status of field water supply.

探讨辽西半干旱地区的农田供水状况．分析表明该区大田作物的耗水来源主要为生长期内大气降水和土壤储水，由于大气降水不足，特别是生长前期的严重缺水是该地区作物减产的一个重要原因，而且还经常出现伏旱和“秋吊”，大气降水占作物耗水量的７５．６％以上，而土壤供水量最高达作物耗水量的２４．４％，作物耗水量与生长期内大气降水呈直线关系．

Studies on the status of field water supply in semiarid area of western Liaoning Province showed that the water consumption by crops mainly came from rainfall in growing season and soil water storage. An insufficient rainfall, and especially, a serious water shortage in early growing season was the important cause for the decrease of crop yield. Water supply from rainfall accounted for 75.6% of water comsumption, and that from soil water storage was up to 24.4%. There was a linear relationship between water consumption by crops and rainfall in growing season.