中文摘要：

冰川前沿裸露地有着暴露年代序列特性,是研究微生物群落结构时空变化的理想地区.通过对1号冰川东支前沿裸露地的微生物学研究发现,从冰土交界处到1675年的冰碛垄,25℃下培养得到细菌数量从5.5×104 CFUs.g-1增加到3.3×106 CFUs.g-1,而微生物总数的变化在暴露年代序列上都没有显著的相关关系;细菌群落结构的主要改变发生在两个阶段,暴露初期和植被盖度明显增加的时候.联系到这两个阶段正好是环境温度与土壤营养水平改变的时期,此结果表明,环境变化是冰川前沿裸露地微生物群落时空变化的主要驱动力.

英文摘要：

Glacier foreland,possessing a chronosequence of exposure,is an ideal area to study microbial community dynamics across space and time.Traditional microbial study in the foreland of the east branch of the Glacier No.1 showed the number of culturable bacteria at 25 ℃ increasing from 5.5×104 CFUs·g-1 at the edge of glacier terminus to 3.3×106 CFUs·g-1 at the moraine of 1675.In contrast,there is no significant correlation between the number of culturable bacteria or total microorganisms and the chronosequence.There were two stages of major change in bacterial population： 1） at the beginning of exposure and 2） at the stage of distinctly increasing vegetation coverage.Consequently,these two stages reflected the change in environmental temperature and the enhancement in soil nutrient level.The results indicate that the change in environment drives the change in microbial community spatially and temporally.