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据大兴安岭根河镇剖面的孢粉分析、１４Ｃ测年并结合沉积地层岩性等资料，揭示该地区晚更新世晚期以来２．５万年期间，生态环境经历了七次变迁。在晚更新世晚期距今２．５～１．３万年期间有三次亚期演变；在早全新世的１．３～０．９万年间经过早、晚二次变迁；中全新世的０．９～０．４年间经过早、晚二次变迁；晚全新世的０．４万年至今。气候的寒温干湿周期０．４万年左右，０．２万年左右发生次一级变化，生态环境随之变迁。
According to the sporopollen analysis and the 14C dating of the Ganghezhen section of the Greater Hinggan Mountains and the lithology of the sedimentary strata, it reveals that during the 25,000 years since the late Pleistocene, the ecological environment underwent seven changes. During the Late Pleistocene, there were three sub-evolutions between 2.5 and 1.3 million years ago; early and late second-order changes occurred during 1.3 to 0.9 million years in the Early Holocene; and mid-Holocene 0 9 ~ 0.4 years after the early and late changes two times; late Holocene 0.4 million so far. Climate cold and wet climate cycle of about 40,000 years, about 0.2 million times the level of change occurs, the ecological environment changes.