1961—2012年黑龙江省冻土最大冻结深度的时空变化特征

Spatiotemporal Variation Characteristics of Maximum Frozen Depth of Frozen Soil in Heilongjiang Province from 1961 to 2012

利用1961—2012年来黑龙江省32个气象台站的逐日冻土观测数据,使用变异系数法、线性趋势估计法、克里金插值法以及突变检验方法,对黑龙江省冻土最大冻结深度的时空变化特征进行了分析。得到如下结论:黑龙江省冻土最大冻结深度年下降速率为-0.67 cm/a,变异系数为9.9%,突变年份出现在20世纪80年代中后期,在60年代最大冻结深度达到最大。之后每10年出现明显的递减趋势,下降速率为12.43 cm/10 a。黑龙江省冻土平均开始冻结日期在10月中旬左右,冻土开始解冻的日期最早出现在2007年3月1日,最晚出现在1972年4月6日。冻结日期在不断提前,而冻土开始冻结日期却在逐步延后,空间分布总体上呈现北高南低的趋势走向。低值区主要位于铁力、通河站点附近,同纬度相比,中部地区的最大冻结深度偏低。

In this paper,the temporal and spatial variation characteristics of the maximum frozen depth of frozen soil in Heilongjiang Province were analyzed by using variation coefficient method,linear trend estimation method,kriging interpolation method and mutation test method based on daily frozen soil observation data of 32 meteorological stations in Heilongjiang Province from 1961 to 2012.The following conclusions were obtained:the annual decrease rate of the maximum frozen depth of frozen soil in Heilongjiang Province was -0.67 cm/a,and the coefficient of variation was 9.9%.The mutation year appeared in the middle and late 1980s,and the maximum frozen depth reached the maximum in 1960s.After that,there was a significant decline trend every decade,with a decline rate of 12.43 cm/10 a.The average freezing date of frozen soil in Heilongjiang Province is around mid-October,and the earliest thawing date of frozen soil was March 1,2007,and the latest appeared on April 6,1972.The freezing date is constantly advanced,while the frozen soil freezing date is gradually postponed.On the whole,the spatial distribution presents a trend of high in the north and low in the south.Compared with latitude,the maximum freezing depth in the central region is low.