High-Resolution Research on Vegetation of Changes Loess Plateau area and the Desert-Loess Transition Zone in Holocene

Many academicians have recently studied on the sediment of Loess by high-resolution pollen analysis.Pollen spectrum in signal section can reflect the vegetation of change in the place.In the case of the same researchmethod,the content of the same pollen in the different section can reflect the distributionof the plant.On the base of the fruits of predecessor,the authors chose and studied eight sections and categories of six sections in two regions,which have the significance of ecologicalindication.We concluded that: in early Holocene,the environment in the Desert-Loess Transition Zone was better than that in Loess Plateau area,but in the late Holocene,it was manifestthat the characteristicsof belt in vegetation.The authors put forward the possible reasons.The conclusion still need deep study.