Species diversity and interspecific association in development sequence of Hippophae rhamn

Species diversity and interspecific association in development sequence of Hippophae rhamnoides

plantations in the Loess Hilly Region, China

Lianjin GUO;Wenhui ZHANG ;Guobin LIU

【期刊名称】《中国高等学校学术文摘·生物学》 【年(卷),期】2008(003)004

【摘要】Based on our field investigation, we analyzed the characteristics of species diversity and interspecific association at different development stages of Hippohae rhamnoides plantations. The results show that the species diversities of the shrub layer, grass layer and the whole community of the H. rhamnoides plantations all fluctu-ated in an \and diversity were higher in the grass layer than in the shrub layer. The shrub species diversity was lower on bare land, but increased gradually with development of the community. The shrub evenness index was higher in 13-year forest stand, while the grass diversity index was higher in the 3-year and 25-year plan-tations and lower in the 8-year plantation. The positive and negative absolute values of interspecific association between H. rhamonides and other principal species chan-ged in a parabolic pattern. The significance level and intensity of interspecific association were lower or weaker in thel3-year plantation, indicating that the species sub-stitution rate slowed down, competition