[Ecological characteristics of Artemisia halodendron community and population on Horqin sandy land]

Based on the analysis of species important values and Shannon-Wiener index of Artemisia halodendron community on different type sandy lands in Horqin, A. halodendron community was classified into three types, i. e., A. halodendron - annual herbage, A. halodendron - perennial grass, and A. frigida - A. scoparia + perennial grass, which distributed on shifting sandy land, semi-fixed sandy land, and fixed sandy land, respectively. With the sand fixed, the community succession was ranked from A. halodendron - annual herbage (pioneer stage, coverage < 10%, Shannon-Wiener index 0. 33) to A. halodendron - perennial grass (coverage 30% to approximately 35%, Shannon-Wiener index 0. 56), and then to A. frigida - A. scoparia + perennial grass (steppe community, coverage 40% to approximately 45%, Shannon-Wiener index 0. 59). The A. halodendron population on shifting sandy land and that planted 5 years ago showed growing age distribution, that planted 18 years ago showed stable age distribution, and that on semi-fixed and fixed sandy lands showed declining age distribution. The results proved that A. halodendron populations had different ecological effects on A. halodendron community.