干旱区生态环境知识资源中心

We examined the impact of plant-plant interactions and sandy desertification disturbance on population structure and spatial distribution of the two desert plant species Anabasis aphylla and Haloxylon ammodendron in the south margin of Junggar Basin, NW China. To explore species-habitat interactions, we compared the population structures of two woody plants and evaluated the growth of A. aphylla population in the different soil types. Furthermore, we used the Wiegand-Moloney O-ring statistic to study the spatial pattern and association of A. aphylla population and H. ammodendron population. We found some differences in the population structure and spatial distribution of A. aphylla and H. ammodendron with regard to the sandy desertification condition, which is also connected with changes in plant-plant interactions. Although an aggregation of A. aphylla and H. ammodendron population was found in each plot, the cause of spatial aggregation and association is different in the three sandy desertification areas. In the diluvial plot, the spatial association of A. aphylla and H. ammodendron seems to reflect a tense negative woody plant interaction. On the other hand, the random labeling null model showed that plant-plant interactions were largely determined by the combined effects of interspecific competition and harsh environments in the diluvial-sandy and sandy plots, contrary to the competitive effect of the early stage of sandy desertification expansion.