Spatial distribution patterns of seedling emergence of Stipagrostis pennata in Gurbantonggut Desert

摘要

The aim of this study was to investigate the spatial distribution patterns and the amounts of seedling density of S. pennata in different sample dunes in Gurbantonggut Desert. Results indicate that spatial patterns of seedling emergence of S. pennata were of general similar with the distribution patterns of its associated standing vegetations, and was greatly associated with spatial distribution of the threshold wind (≥6m.s~(-1)) frequency from the various directions. There existed a significant difference in its seedling emergence patterns among the different parts of the dunes and the different directions around its parent vegetation beds. The highest seedling density was found to be on the top parts of sampling dunes and at the underlayer of standing vegetation beds of S. pennata, and higher seedling densities usually took place in the leeward side of the vegetation beds. These results had revealed the ecological characteristics of the population distribution rule and the recruitments mechanism of S. pennata.