塔木素天然梭梭林空间分布及其与林地地貌起伏变化的关系

Spatial distribution of natural Haloxylon ammodendron forest in relation to topographic undulations in Tamushu

为探讨天然梭梭(Haloxylon ammodendron(C.A.Meyer)Bunge)林空间分布及其与林地地貌起伏变化(GPS点海拔)的关系,本研究以巴丹吉林沙漠东缘的塔木素野生肉苁蓉及梭梭产籽基地为试验区,以区域内梭梭林为研究对象,采用样线法调查梭梭株高和冠幅直径,结合GPS点统计梭梭密度,运用不同分析方法探讨其相互关系。结果表明,梭梭数量特征与林地地貌起伏变化存在极显著的相关性(P<0.01),在自相关尺度范围内,梭梭数量特征与林地地貌起伏变化均主要受结构性因素影响,空间自相关程度较高,空间分布格局比较简单。梭梭密度、高度、冠幅直径及林地地貌起伏变化复杂程度依次降低。梭梭入侵沙丘由其南端开始,当梭梭入侵以后,受试验地常年合成风向影响迅速扩散,使得沙丘向前推移的速度减慢,起到了防风固沙的作用。这一研究结果为产籽基地建设提供了科学依据。

In order to study the spatial distribution of Tamushu natural sacsaoul（ Haloxylon ammodendron（ C. A. Meyer） Bunge） forest and its relationship with topographic undulation change（ GPS altitude point）,Tamushu wild Cistanche and H. ammodendron seed production base in Tamushu region at the eastern edge of the Badain Jaran Desert was chosen as test area and its H.ammodendron forest as study object. Line transect was used to survey plant height and crown diameter of H. ammodendron and H. ammodendron density was counted in combination with GPS points. Various analysis methods were then used to explore the relationship of spatial distribution of natural H. ammodendron forest with topographic undulations. It was found that quantitative features of H. ammodendron forest had highly significant correlation（ P〈0.01） with topographic undulation,and both were affected by structural factors within the autocorrelation scale,in which the spatial autocorrelation was to a high degree and spatial distribution pattern was simple. Furthermore,the complexities of density,height,crown diameter of H. ammodendron forest and topographic undulation decreased successively. The results also showed that H. ammodendron invaded the sand dune from its southern side and spread rapidly due to prevailing winds in this region. Hence,the dunes moved forward slowly,functioning as wind prevention and sand fixation.The results of this study provide a scientific reference for establishment of seed production base.