华北地区暴雪覆盖与土壤墒情关系初探——以邯郸市为例

Preliminary Study on Relationship between Snow Covers and Soil Moisture in North China

研究土壤冬季储水量对整个冬季土壤墒情尤为重要,可以预测解冻后土壤墒情变化为3月中旬华北地区开展农田灌溉提供理论依据。利用华北地区2009年11月的一次强降雪气象资料、2002-2008年多年平均同期降水资料和土壤墒情实测的面尺度资料,对降雪量、降雪时间和土壤含水量以及相互影响关系进行了分析。研究结果表明:积雪覆盖对土壤含水量有显著影响。和同等水量的降雨相比,冻融土壤平均含水量高出多年平均土壤含水量10%以上;积雪覆盖导致土壤各层含水量随时间变化波动较为均匀,使土壤水分下渗延时效应明显;积雪覆盖有利于维持土壤含水量的稳定,同时使土壤含水量有增加的趋势。

It is especially important to understand the winter water storage capacity of slope to study the soil moisture of the whole winter,because it can be used to predict the change of soil moisture after defrosting,which can provide a theoretical basis for irrigation in mid-March in northern China.The interactive relationship among snowfall,snow and soil moisture is analyzed based on the snowstorm data in northern China in November 2009,2002-2008 multi-year average precipitation date and the same period of the surface scale soil moisture data in this paper.The results show that the snowstorm on the soil has significant impact on moisture content.Compared with the rainfall of the same quantity,the moisture content of freeze-thawing soil is at least 10% higher than that of average years;snow cover leads to an even fluctuation of each soil moisture with time variation,and soil freezing and thawing causes the frequent change of soil water and then an obvious delay effect of soil moisture;snow cover helps to maintain the stability of soil moisture content and meanwhile makes the tendency of the soil-moisture increase evidently.