干旱区生态环境知识资源中心

The Haloxylon ammodendron natural desert forest is an important vegetation formation and has a large distribution area in Junggar Basin, Xinjiang Province, China. In this paper, H. ammodendron populations were mapped, characterized and the spatial distribution patterns and spatial associations of H ammodendron among different life stages (seedlings - S, juveniles - J, mature - M, overmaturer - O) were analyzed using O-ring univariate O-11(r) and bivariate I-12(r) statistics. We found that:

(1) H ammodendron was a regenerating population.

(2) H ammodendron (S), H ammodendron (J), and H ammodendron (M) showed significant aggregations at scale 0-8 m, 0-27 m, and 0-35 m, respectively, whereas H ammodendron (0) tended to have random distributions at almost all scales.

(3) The spatial associations between different life stages of H ammodendron tended to turn from positive to negative if their size differences are enlarged increasingly. Strongly positive associations were found at small scales for only two pairs: H ammodendron (S)-H ammodendron (J), H ammodendron (T)-H ammodendron (M).