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黄河源盆地位于青藏高原东北部,是黄河的源头地区,对环境和气候变化非常敏感。对黄河源盆地中的河湖相沉积物进行了孢粉分析,获得丰富的孢粉数据,结果显示孢粉组合以菊科、蒿科、藜科、禾本科、松、桦等草本和木本植物花粉为主。通过对各类植物的孢粉组合特征分析,揭示了黄河源地区早更新世以来古植被、古气候的演替和变化。其演变经历了4个阶段:第一阶段223.9～90.1万年,为森林草原环境,反映了温暖潮湿的气候;第二阶段90.1～35万年,为灌丛草原环境,反映了总体干冷的气候;第三阶段35～2.8万年,为稀树草甸草原环境,属湿润寒冷的气候;第四阶段2.8～0.8万年,为荒漠草原环境,反应干冷的气候。
Located in the northeast of the Qinghai-Tibet Plateau, the Yellow River source basin is the source of the Yellow River and is very sensitive to environmental and climate change. Pollen analysis of the lacustrine facies sediments in the Yellow River source basin resulted in abundant spore-pollen data. The results showed that the spore-pollen assemblages are mainly composed of Compositae, Artemisia, Chenopodiaceae, Poaceae, Pinus thunbergii, Plant pollen based. Through the analysis of the characteristics of sporopollen assemblages of various plants, the succession and change of paleo-climate and paleoclimate since the Early Pleistocene in the Yellow River source area have been revealed. Its evolution experienced four stages: the first phase of 223.9 ~ 90.1 million years, the forest grassland environment, reflecting the warm and humid climate; the second phase of 90.1 to 350,000 years, for the shrub grassland environment, reflecting the overall dry and cold climate ; The third stage of 35 ~ 28000 years, is a thin grass meadow grassland environment, is a humid climate; 2.8 to 0.8 million in the fourth phase of the desert grassland environment, dry and cold response climate.