The study on spore pollen and geochemical elements of the Holocene lacustrine sediment of Bosten lake

which locates at the northern part of southern Xinjiang shows that since about 12 kabp

this area was predominated consectively by drought.But according to the sporepollen combination and density

which can reflect to a certain degree the changes of desert type vegetation cover

together with the geochemical contents and sedimentary feature

several relative humid periodes still can be divided.Another important feature is also revealed

that ia during each neoglacial epoch of the northern hemisphere

spore pollen density appeard higher

humide like geochemical contents increase

and leva developed in sediment.During the Holocene Optimum Periode

climate tended to warm dry more and more

which differentiated from the Balikun lake in northeastern Xinjiang.The Holocene environmental sequence of Bosten Lake is basically coincidence with that revealed by Balikun Lake and Aibi lake in northern Xinjiang and Lopnur in southern Xinjiang

and also with the monsoonal area in eastern China and other areas in the world

reflect that the Holocene environmental changes of the northern part of southern Xinjiang is controlled by the general regulation of global environmental development

but also has distinct regional charactristics.