人为干扰对桫椤群落植物种间协变影响的研究

Study on Effect of Human Disturbance on Interspecific Covariation of Alsophila spinulosa Community

通过采用种间协变的Perason积矩相关分析和Spearman秩相关分析方法(r公式),以及X2检验公式测定种间联结,对重庆市涪陵区磨盘沟桫椤(Alsophilaspinulosa)自然保护区的2个受人为干扰程度不同的样地里的桫椤与12个主要草本植物之间的种间关系进行了分析研究,经过种间联结X2检验后,得出以下结论:①在样地1中,正协变的种对较多,这说明在人为干扰较小的环境条件下,不同的植物种利用资源时表现出一定的相似性,种间多度在多数情况下随之增加;在样地2中,负协变的种对较多,表明由于人为干扰,生境破碎化,桫椤种群呈斑块状分布,以致其间杂草大量侵入,种间竞争激烈,一种植物的生长会抑制其它植物的生长.②X2检验公式和r公式能够较好地反映桫椤群落在不同干扰强度作用下主要种间的协变关系,较客观地指示了联结种对在植物空间结构中的格局.

Interspecific covariation between Alsophila spinulosa and 12 herb species of 2 spots in Alsophila spinulosa community, which were disturbed by different intensity, in Mopangou, Fuling district of Chongqing, was analyzed by Pearson product moment correlation, Spearman rank correlation and X^2-test. The results showed ① There were many positive interspecific covariation pairs in spot 1. It indicated resources utilizing way of most species was similar and species abundance tended to increase along with it in the community, due to light human disturbance intensity in spot 1. While, many negative pairs in spot 2, the reasons were Alsophila spinulosa population was distributed in many patches, caused by great human disturbance, and growth of a species tended to restrain that of others, because of much herb species invading and strong interspecific competitions. ② X^2-test and r formula were available to reflect interspecific covariation relationship of main populations in Alsophila spinulosa community in condition of different disturbance intensity. They also could be used to show pattern of association pairs on space structure.