种群格局分析..doc

+中国西北准噶尔盆地南缘荒漠绿洲过渡带的主要木本植物的空间格局和关联 摘要：物种的空间格局和关联在揭示物种间相互影响以及环境的相互影响是非常重要的。而且它对理解物种相互影响和基本生态过程与温带荒漠植被方面具有重要意义。在本文中，函数g（r）用于描述中国西北准噶尔盆地的荒漠绿洲过渡带的三个1公顷的荒漠植物地块中四种主要木本种间的空间格局和关联特征。完整的空间随机零模型（CSR）显示四个物种在小范围（20m）内呈现出显著聚集。无叶假木贼和白刺，梭梭和红砂在与独立零模型小尺度空间上呈现正相关，而无叶假木贼和梭梭，无叶假木贼和红砂，红砂和白刺在小范围或者中等范围（20-60m）内呈现负相关。随机标签零模型表明无叶假木贼的枯立木主要是由种内和种间竞争的综合作用决定。此外，研究结果还表明，生境异质性和沙漠化这两个主要因素在准噶尔盆地南缘荒漠绿洲过渡带的木质物种空间分布格局和关联中起着重要的作用。因此，规划造林和开发保护策略时，物种特征在空间格局和关联性上的差异性应该予以重视。 关键词：空间格局，空间关联，生境异质性，荒漠绿洲过渡带，准噶尔盆地 Spatial patterns and associations of dominant woody species in desert-oasis ecotone of South Junggar Basin, NW China Abstract: Spatial patterns and associations of plant species are important for revealing how species interact with each other and with the environment, and hence have important implications for the understanding of species interaction and underlying ecological processes with apparent patterns in temperate desert vegetation. In this paper, the function g (r) was used to characterize the spatial patterns and associations of four dominant woody species in three 1-ha desert plant plots in the desert-oasis ecotone of South Junggar Basin, NW China. The complete spatial randomness null model (CSR) showed four species exhibited significant aggregations at small scales ( 20 m). A. aphylla and N. roborowskii, H. ammodendron and R. songarica were spatially positive associations at small scales with the independent null model, while A. aphylla and H. ammodendron, A. aphylla and R. songarica, R. songarica and N. roborowskii species pairs exhibited negative associations at small or moderate scales (20–60 m) in our study. The random labeling null model showed that dead standing plants of A. aphylla were largely determined by the combined effects of intra- and interspecific competition. In addition, the results also indicated that the two main factors of habitat heterogeneity and sandy desertification play important roles in determining spatial distribution patterns and associations of woody species i