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黄河源区位于青藏高原多年冻土区东北部边缘地带,是季节冻土、岛状多年冻土和在大片连续多年冻土并存地带.多年冻土层在垂向分布上有衔接状和不衔接状两大类.不衔接状又可分为浅埋藏(<8m)、深埋藏(>8m)和双层多年冻土等形式.从20世纪80年代以来,源区气温以0.02℃.a-1增温率持续上升,人类经济活动日益增强,导致冻土呈区域性退化.多年冻土下界普遍升高50～80m,最大季节冻深平均减少了0.12m,浅层地下水温度上升0.5～0.7℃.冻土退化总体趋势是由大片状分布逐渐变为岛状、斑状分布,多年冻土层变薄,冻土面积缩小,融区范围扩大.部分多年冻土岛完全消失变为季节冻土.
The Yellow River source area is located in the northeastern marginal zone of the permafrost region on the Qinghai-Tibet Plateau, and is a seasonal frozen land, island-shaped permafrost and coexistence of large areas of permafrost. Permafrost in the vertical distribution of convergence and not convergence The two types of unconformity can be divided into shallow burial (<8m), deep burial (> 8m) and double-layer permafrost, etc. Since the 1980s, the temperature in the source area has been increased by 0.02 ℃ .a- 1 Increasing warming rate and increasing human economic activity led to the regional degradation of permafrost.The permafrost generally increased 50 ~ 80m in the lower boundary, 0.12m in the maximum season and 0.5 ~ 0.7 in shallow groundwater ℃. The general trend of permafrost degeneration is that the distribution of large platelets gradually changes into islands and patches, the permafrost layer becomes thinner, the permafrost area shrinks, and the melting zone expands. Some permafrost islands disappear completely and become frozen in season earth.