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主要根据孢粉分析结果,并结合磁化率、碳酸钙恢复了陇西黄土高原地区全新世期间植被、气候的变化过程.结果表明全新世气候存在3个大的阶段,全新世早期(11~7kaB.P.)气候以寒冷为主要特点,中全新世(7~3kaB.P.)气候温暖湿润,晚全新世(3~0kaB.P.)气候以干旱为主要特征.研究区全新世大多数时期为草原植被,仅在8.5~7.8kaB.P.短期内形成针叶林植被,全新世期间曾出现5次干旱事件,它们具有大约2ka的准周期,并具有一定的突发性.距今4.2ka前后曾出现洪水事件.
According to the results of sporopollen analysis and the magnetic susceptibility, calcium carbonate restored the process of vegetation and climate during the Holocene in Longxi Loess Plateau. The results show that there are three major stages of the Holocene climate. In the early Holocene (11-7 kaB.P.), the climate is dominated by the cold. The mid-Holocene (7-3 kaB.P.) climate is warm and humid. In the late Holocene (3 ~ 0kaB.P.) The climate is dominated by drought. Most of Holocene in the study area are grassland vegetation, only 8.5 ~ 7.8kaB. P. In the short term, the coniferous forest was formed. During the Holocene, there were 5 drought events. They had a quasi-period of about 2ka and had some suddenness. 4.2ka ago there have been floods.