喀斯特峡谷区石漠化演变中群落多样性的响应

Response of Plant Community Diversity to Rocky Desertification Succession in Karst Valley Area

以喀斯特峡谷区石漠化生态系统中植物群落为研究对象,野外定点监测群落的基本特征,实验室分析石漠化不同演变阶段植物群落的多样性指数;运用空间代替时间方法,探讨了石漠化演变过程中植物群落多样性的响应,旨在为典型喀斯特地区的生态系统恢复重建提供参考。结果表明:(1)示范区内植物群落以人工植被为主;(2)在潜在和轻度石漠化阶段,重要值较高的植物群落有皇竹草(Pennisetum sinese Roxb)、荩草[Arthraxon hispidus(Thunb.)Makino]等,在中度和强度石漠化阶段,重要值占据绝对优势的有花椒(Zanthoxylum bungeanum Maxim.)、砂仁(Amomum villosum Lour.)、仙人掌[Opuntia stricta(Haw.)Haw.var.dillenii(Ker-Gawl.)Benson]等植物;(3)伴随着石漠化的演变,Simpson指数表现为逐渐下降的规律,Shannon-Winner多样性指数表现出先增大后减小的规律,Pielou均匀度指数呈现出逐渐上升的规律,Margalef丰富度指数呈现出先扬后抑的规律。

In view of plant community in Karst valley area,the diversity of plant communities at different stages of the rocky desertification was studied by field survey and laboratory analysis.Using the method of space instead of time,the response of plant community diversity in the process of rocky desertification evolution is discussed in order to provide a reference for the restoration and reconstruction of ecosystem in typical Karst area.The results show that：（1）the plant community in the demonstration area is dominated by artificial vegetation;（2）at potential and slight rocky desertification stage,the important values of Pennisetum sinese Roxb and Arthraxon hispidus（Thunb.）Makino are high,at moderate and high stages,the IV of Zanthoxylum bungeanum Maxim.,Amomum villosum Lour.and Opuntia stricta（Haw.）Haw.var.dillenii（Ker-Gawl.）Benson occupy the superiority;（3）along with the evolution of Karst rocky desertification,Simpson index decreased gradually,Shannon-Winner index increased first and then decreased,Pielou index presented a gradually rising trend,Margalef index ascended slightly prior to the intensive decline.