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冰川斑块对气候变化的响应不仅表现在冰川长度和面积的变化,而且其格局在斑块数量、形状、平均欧几里德距离、连通度和最大斑块指数等指标上都发生了显著的变化。运用RS和GIS技术对祁连山东段典型地区2001—2009年间冰川斑块动态的分析表明:研究区冰川斑块面积减少了15.39%,面积<1 hm2的小斑块数量消失了50%以上,斑块形状指数在总体和分级层次上都呈减少的趋势,最大斑块的优势降低。由于小斑块消融和大斑块收缩,使斑块间平均欧几里德距离增加了16.56 m。斑块连通度具有尺度依赖性,当在阈限值<7 000 m时,2009年的冰川斑块连通度大于2001年;当阈限值>7 000 m时,趋势相反。7 000～8 000 m之间是尺度特征的转折点。从斑块动态变化来看,冰川斑块动态以消融斑块为主,消融面积为744.30 hm2,占起始面积的16.53%;新生斑块也同时发生,仅增加起始面积的1.15%。但是,消融和新生斑块发生的数量较多,分别为762和367个,冰川单个斑块面积大小与消融面积呈正相关。
The response of glacial patches to climate change is not only reflected in the change of glacier length and area, but also the pattern of significant changes in the number of patches, shape, average Euclidean distance, connectivity and maximum patch index Variety. The analysis of glacial plaque dynamics in typical areas of eastern Qilian Mountains from 2001 to 2009 using RS and GIS shows that glacial plaque area decreased by 15.39% in the study area and the number of small plaques with area <1 hm2 disappeared by more than 50% The block shape index tends to decrease at the overall and graded level, and the advantage of the largest patch is reduced. Due to the small plaque ablation and large plaque contraction, the average Euclidean distance between plaques increased by 16.56 m. Plaque connectivity is scale-dependent. When the threshold is less than 7 000 m, the glacier patch connectivity in 2009 is greater than that in 2001; when the threshold is> 7 000 m, the trend is opposite. 7 000 ~ 8 000 m is the turning point of scale features. From the dynamic changes of plaque, glacial plaque dynamic mainly in the ablation plaque, ablation area of 744.30 hm2, accounting for 16.53% of the initial area; new plaque also occurred at the same time, only increasing the initial area of 1.15%. However, the number of ablation and nascent plaques occurred more frequently, which were 762 and 367, respectively. The area of single plaque and the area of ablation were positively correlated.