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昆仑山垭口羌塘组和三岔河组的孢粉分析表明 ,羌塘高原的干旱环境在早更新世时已经确立 .孢粉反映的古气候以干湿变化为主 ,冷暖变化不明显 ,可能与青藏高原隆起有关 .在 2～ 1.8MaBP ,羌塘高原的古植被是以麻黄、藜科、蒿等为主的荒漠或草原荒漠植被 ,1.8～ 1.3MaBP气候变得比较温和稍湿 ,古植被演变成草原植被 ,在 1～ 0 .6 8MaBP ,本区在构造抬升和冰期气候控制之下植被极不发育 .0 .6 8～ 0 .6 5MaBP可能为一小间冰段 ,古植被为蒿、藜科、麻黄和众多草本植物组成的草原植被 ,羌塘组和三岔河组缺失 6 5 0～ 35 0kaBP的沉积 ,可能仍为荒漠植被 .倒数第二次间冰期时期 ,在三岔河组的沟谷里可能生长着云、冷杉组成的暗针叶林 .随后 ,古气候明显变干 ,针叶林消失 ;6 0kaBP之后 ,气候进一步变干 ,古植被又演变成荒漠植被
The pollen analysis of the Quntang Formation and Sanchahe Formation in the Kunlun Mountains shows that the arid environment of the Qiangtang Plateau was established during the Early Pleistocene. The paleoclimate reflected by sporopollen was dominated by wet and dry changes, Which is related to the uplift of the Qinghai-Tibet Plateau. The ancient vegetation of the Qiangtang Plateau was desert or grassland desert vegetation dominated by Ephedra, Chenopodiaceae and Artemisia in the period of 2 ~ 1.8MaBP. The climate of 1.8 ~ 1.3MaBP became milder and wetter. Evolved into a prairie vegetation in the 1 ~ 0.86MaBP, the area under the tectonic uplift and glacial climate control under extremely undeveloped vegetation .0.68 ~ 0.56MaBP may be a small ice section, the ancient vegetation Artemisia , Chenopodiaceae, Ephedra and many herbaceous vegetation, the Qiangtang Formation and Sanchahe Formation are missing from 650 to 3580 ka BP, probably still desert vegetation. In the penultimate interglacial period, After that, the paleoclimate obviously dried up and the coniferous forest disappeared. After 60 kaBP, the climate further dried up and the ancient vegetation turned into desert vegetation