甘肃陇南地震扰动区植被群落特征

Community characteristics of vegetation in earthquake disturbed zone in Longnan,Gansu

地震扰动对当地生态环境造成极大的破坏,引起植被群落种类组成、群落结构的变化,本研究采用样带结合海拔梯度的方法,于2013年8-9月,调查和研究了甘肃陇南武都区清水沟植被群落的种类组成、群落结构受地震扰动后的现状。结果表明,研究区内共发现34种植物,分属16科30属,主要以禾本科和菊科植物为主,群落垂直结构明显,大体分为3层;植物群落中多年生草本植物种类最多,是优势生活型,其次是灌木、藤本,无乔木分布;Shannon-Wiener多样性指数(H')和Pielou均匀度指数(E)表现为中坡位>下坡位>上坡位,Simpson优势度指数(D)表现为上坡位>下坡位>中坡位。

The seismic disturbance causes great damages to the local ecological environment,which leads to the changes of species composition and structure of vegetation community. The present paper investigated and analyzed the species composition and structure of vegetation community after earthquake disturbance in Qingshui Gully,Wudu District,Longnan City of Gansu Province from August to September of 2013 using the methods of belt transect combined with altitudinal gradient. The results showed that there were 34 plant species which belong to 30 genera,16 families in the study area although the main vegetations were Gramineae and Compositae plants. There was obvious vertical structure of vegetation community which could be divided into three layers. The perennial herbs were dominant which had the highest species number in the community. The shrub and vine followed and no arbor was observed. The Shannon-Wiener index（ H＇） and Pielou evenness index（ E） decreased in the following order： middle slope〉 lower slope〉 upper slope,and Simpson dominance index（ D） decreased in the following order： upper slope〉 lower slope〉 middle slope.