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若尔盖ＲＭ孔上部６３７ｃｍ的花粉分析研究表明，在２２０００－１８０００ａＢ．Ｐ．，植被以高山草甸和荒漠草原为主，气候较现在寒冷干燥；１８０００－１３０００ａＢ．Ｐ．，主要是高山、亚高山草甸，出现亚高山灌丛，气温趋于升高，但仍干燥；１３０００－１１０００ａＢ．Ｐ，植被以亚高山禾草草甸为主；亚高山灌丛发展，可能已出现亚高山常绿针叶林，气温进一步上升，到后期己接近现在，湿度有所增加；１１０００－７０００ａＢ．Ｐ．，亚高山常绿针叶林扩张，亚高山灌丛在地方性植被中的比重又有所增加，草甸除禾草草甸外，可能出现亚高山莎草草甸或沼泽草甸，气温和湿度均比前期增高，西南季风在１１０００ａＢ．Ｐ．前后侵入本区；７００００－３３００ａＢ．Ｐ．，亚高山常绿针叶林大规模扩张，亚高山灌丛基本上被其取代，地方性植被主要是禾草草甸和莎草草甸或沼泽草甸，气候温暖潮湿；３３００－１９００ａＢ．Ｐ．，亚高山常绿针叶林退缩，禾草草甸可能被杂草草甸所取代，仍有莎草草甸或沼泽草甸，气温下降，湿度下降，西南季风逐渐减弱；１９００－１４００ａＢ．Ｐ．；针叶林进一步退缩，且冷杉在针叶林中的含量大于云杉，莎草草甸或沼泽草甸的规模扩大，气温进一步下降；１４００ａ?
Ruoergai RM hole 637cm above the pollen analysis studies have shown that at 22000-18000aB. P. The vegetation is dominated by alpine meadows and desert grasslands, and the climate is colder and drier than it is now; 18000-13000aB. P. , Mainly high mountains, subalpine meadows, sub-alpine shrubs appear, the temperature tends to rise, but still dry; 13000-11000aB. P, vegetation is dominated by sub-alpine grass meadow; sub-alpine shrub development may have sub-alpine evergreen coniferous forest, the temperature rose further, to the late has been close to the present, humidity has increased; 11000-7000aB. P. , Sub-alpine evergreen coniferous forest expansion, sub-alpine shrubs in the proportion of local vegetation has increased, the meadow in addition to grasses meadow, there may be sub-sedge meadow or marsh meadow, temperature and Humidity higher than the previous period, the southwest monsoon at 11000aB. P. Invaded the area before and after; 70000-3300aB. P. , The subtropical evergreen coniferous forest expanded on a large scale, the subalpine shrubs were basically replaced by it, and the endemic vegetation was mainly grass meadow and sedge meadow or swamp meadow with warm and humid climate; 3300-1900aB. P. , The subalpine evergreen coniferous forest retreats, and the grassy meadow may be replaced by weedy meadow. There are still sedge meadow or marsh meadow. The temperature drops, the humidity decreases and the southwest monsoon declines gradually. 1900-1400aB. P. ; Coniferous forest further retreat, and the content of fir in coniferous forest is greater than that of spruce, the size of sedge meadow or swamp meadow expands, the temperature further decreases; 1400a?