新疆开都河流域季节性冻土特征的控制和影响因子分析

全球变暖使季节性冻土范围逐渐缩小,而季节性冻土对春季径流,尤其是春季洪峰的影响使得该方面的研究更为重要。为了分析季节性冻土广泛分布的山区不同海拔高度条件下季节性冻土发育和融化期影响因子的差异,采用通径分析方法对开都河流域不同海拔高度季节性冻土最大冻结深度和解冻日数的影响因子进行了分析。结果表明,不同海拔高度这两者的影响因子差异不大,但其控制因子存在差异。季节性冻土最大冻结深度的控制因子由低海拔处的负积温和最大积雪深度转为中高海拔处的平均相对湿度;解冻日数的控制因子由低海拔处的平均风速和最大冻结深度转变为高海拔处的平均相对湿度。该差异主要由不同海拔高度的地理位置和局地气候条件等决定。

Controlling and Influencing Factors on the Basic Features of Seasonally Frozen Soil in Kaidu River Basin

The extent of seasonally frozen soil is shrinking under global warming. The influence of seasonally frozen soil on springrunoff, especially on the spring peak flow is making the concerned study necessary. In order to analyze the influence and controllingfactors of seasonally frozen soil in the mountain areas with different elevation, this study used the path analysis method to analyzethe influence and controlling factors of the maximum depth of frost penetration and thawing days in the Kaidu River basin.The results indicate that the influencing factors of the maximum depth of frost penetration and thawing days are similar under differentelevation, while the controlling factors are different. The controlling factors of the maximum depth of frost penetration changefrom the negative accumulative temperature and maximum snow depth in lower elevation to average relative moisture in middle andhigh elevation. The controlling factor of the thawing days change from the average wind speed and maximum frozen depth in lowerelevation to average relative moisture in high elevation. The difference is primarily determined by the geophysical condition and localclimate condition in different elevations.