Relationship between the surface pollen and modern vegetation in Zoigê Plateau, northern Sichuan, China.

In order to investigate the relationship between the surface pollen and modern vegetation, surface soil samples collected from 34 sites in Zoigê Plateau were analyzed, and then the pollen assemblages of every zone were obtained. It is found that pollen assemblages of surface soil samples generally reflect the whole features of the modern vegetation, and they are basically similar in the spatial arrangement, types and the main and dominant genera. But pollen assemblages of surface soil samples aren't completely equal to the vegetation composition, maybe because of the influences of mankind's activities, pollen preservation, pollen production, foreign pollen and pollen identification. The representation of pollen in surface soil is different between families and genera. The tree pollens such as Pinus is over-represented, and Picea pollens are moderately represented, but Betula isn′t over-represented; the herb pollens such as Compositae is well represented; Artemisia and Chenopodiaceae are equal-represented, but Gramineae and Cyperaceae are under-represented; the fern spores are equal-represented.