摘要
正冻土体冻结缘的水势梯度导致非冻结土中的水分向冻结土体迁移,使融解后的土壤水分含量显著提高。然而,土壤水分增加的数量决定于冻结前土壤水分的剖面分布状况。根据田间试验结果,利用土壤冻融作用对土壤剖面水分的再分布,储水灌溉时间可以提前至9月下旬至10月中旬,灌溉定额可以降低至60m3/亩,甚至40m3/亩。灌溉后及时地进行地面覆盖保墒措施,可以改善较早灌溉和低定额灌溉条件下在播种期的土壤墒情,显著提高作物的出苗率。
Soil moisture increases due to freezing because of water migration caused by water potential of frozen soil fringe However, increase amount depends on the moisture distribution in the soil profile before freezing According to an experiment conducted in field, in connection with mention above, it is suggested that the time for water-storing irrigation can move up to the last ten-day period of September or the middle of October, the amount of water supplying can reduce to 60 m 3 /mu even to 40 m 3 /mu, and having a soil cover after water-storing irrigation can improve the soil moisture content in spite of earlier irrigation and lower water supplying, increasing crop emergence rate
出处
《冰川冻土》
CSCD
北大核心
1997年第4期328-333,共6页
Journal of Glaciology and Geocryology
基金
西部资料与环境科学研究中心课题
关键词
土壤水分
冻融
季节性
农业生产
seasonal freezing soil, water-storing irrigation, soil covers, water-saving agriculture