Pollen in surface soil at the southern slope of western Tianshan, China.

Abstract

We analyzed 52 pollen samples of surface soils from the southern slope of western Tian-shan, China, to understand the relationship between the surface pollen and modern vegetation, and the significance of the Artemisia/Chenopodiaceae (A/C). The results showed that there were five vegetation zones from the mountain top to the foot, i.e., alpine desert zone, alpine meadow zone, meadow and steppe zone, mountain desert zone, and typical desert zone. The typical taxa were Artemisia, Chenopodiaceae, Poaceae and Ephedra. The surface pollen assemblages greatly differed across different vegetation zones in this area. Surface pollen in the southern slope of the western Tianshan Mountains was affected by the northern slope, with the impacts increasing with the increases of altitude. The A/C increased with altitude, peaked in the alpine meadow zone, and then decreased, which could effectively indicate the vertical moisture change. Given the great fluctuation of A/C value, when using this ratio to reconstruct climate and environment, attention should be paid to the fact that high values caused by human activities and other factors may lead to misjudgments.