干旱区生态环境知识资源中心

Although Haloxylon ammodendron (C.A. Mey.) Bunge (Chenopodiaceae) is the dominant species in the Gurbantunggut desert; few studies have examined the natural regeneration of seedlings and microhabitat effects on regeneration. The age classes of regenerated seedlings were investigated and the differences between the different microhabitats in the Mosuowan region of Gurbantunggut desert, China, were examined. The highest age class was found to be 3-year old seedlings, at an average of 116.7 stems per hectare. The correlations between 5-year-old and 6-year-old seedlings (R-2=0.69, p < 0.01), mature trees and 5-year-old seedlings (R-2=0.54, p < 0.05), and mature trees and 6-year-old-seedlings (R-2=0.55, p < 0.05) were significant. The fertile land under H. ammodendron adult trees was not conducive to seedling regeneration in the sampling areas. The withered herbaceous cover layer ranged from 1.70% to 14.50%, with an average of 5.92% +/- 1.47 SE. H. ammodendron seedlings regenerated best under the withered herbaceous layer, with a regeneration rate of 180.56 +/- 33.54 stems per hectare. We concluded that: (1) natural H. ammodendron regeneration can benefit from withered herbaceous plants; (2) during the ecological restoration of H. ammodendron populations, an enclosure policy against grazing should be applied in order to protect the herbs and (3) where there is bare ground or mobile dunes without vegetation, checkerboards should be constructed and fixed to the sand surface in order to promote H. ammodendron seed settlement. A conceptual model of H. ammodendron seedling regeneration is also presented in this paper.