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为了了解黄土高原中部近一万年以来古气候演化特征,通过对关中富平剖面的地质调查、密集采样和31个样品的孢粉分析,将孢粉图式划分为Ⅰ、Ⅱ、Ⅲ三个带分别代表早、中、晚三个时期的孢粉带:Ⅰ带为松-菊-香蒲组合带,以草本植物花粉占优势,针叶树植物花粉含量较高为特征;Ⅱ带为松-栎-蒿-环纹藻组合带,以乔木花粉增加,草本植物花粉减少为特征;Ⅲ带为栎-松-蒿组合带,以草本植物花粉增加,乔木花粉减少为特征。结果表明:早全新世植被为森林草原-干草原,气候干凉-干冷;中全新世植被为森林草原与针阔叶混交林草原,气候温暖半湿润;晚全新世植被为森林草原或疏林草原,气候干旱偏暖-温凉干旱。
In order to know the paleoclimate evolution characteristics in the middle of the Loess Plateau over the past 10,000 years, the sporo-pollen patterns were divided into three zones Ⅰ, Ⅱ and Ⅲ through geological survey, intensive sampling and sporopollen analysis of 31 samples in the Fuping section of the Guanzhong Plain They represent the early, middle and late stages of the three sporopollen belt: Ⅰ for the pine - chrysanthemum - cattail combination zone, with the dominant herbaceous pollen, conifer plant pollen content is high; Ⅱ with pine - oak - Artemisia - Ring-shaped algae combination zone, characterized by the increase of arbor pollen and the decrease of pollen of herbaceous plant; the third zone is a combination of oak-pine-Artemisia annuus, characterized by the increase of pollen of herbaceous plants and the reduction of arbor pollen. The results show that: the Early Holocene vegetation is the forest steppe - steppe, the climate is cool and dry - dry and cold; the mid-Holocene is the forest steppe and the coniferous and broadleaf mixed forest steppe, the climate is warm and semi-humid; the Late Holocene is the forest steppe or sparse forest Grassland, the climate is warm and warm - cool and dry.