洛河中游河岸带不同生境类型中物种多样性研究

为研究河岸带植被不同生境类型中物种多样性变化格局,在洛河中游沿河岸带通过样地调查,采用Patrick丰富度指数(R)、McIntosh均匀度指数(E)、Simpson优势度指数(C)、Shannon-Wiener多样性指数(H)、Simpson多样性指数(D)对洛河中游河岸带不同生境类型(河滩、农田、撂荒地和林地)草本层的物种多样性进行评价,利用重要值对多样性指数中的Ni进行无偏估计.结果表明:洛河中游河岸带植物种类丰富,有33科,97属,141种,分布最多的为菊科,其次是禾本科.沿洛河河岸带不同生境类型中,物种多样性各项指标有一个明显的变化格局:丰富度指数中,河滩>林地>撂荒地>农田;多样性指数(Shannon-Wiener多样性指数和Simpson多样性指数)中,河滩>林地≈撂荒地>农田;农田均匀度最高,且优势度也最高.

Study on the Species Diversity of Different Habitat Types in the Middle Luo River Riparian Zone

Community species diversity is an important component of biodiversity.Biodiversity indexes are widely used for evaluating the quality of biological communities and ecosystems.The Luo River is the largest southern tributary of the lower Yellow River.In July and August,2008,the authors investigated riparian plant species diversity along the middle Luo River,setting up 7 sites.The authors identified four habitat types(farmland,old-field,woodland,and riparian) at each site according to landscape elements(patch type and corridor type),selecting a study plot(20 m×20 m) of each habitat type.Each plot consisted of five 1 m × 1 m quadrats(the four corners and the center).We recorded the frequency,density,coverage,height and phenophase of plant species present in the quadrats,as well as ecological conditions of the sampling sites.The authors found 141 plant species belonging to 33 families in this survey.Using data collected from the sampling plots,the authors calculated species importance values,which were in turn used to compute Patrick richness index(R),McIntosh evenness index(E),Simpson dominance index(C),Shannon-Wiener diversity index(H) and Simpson diversity index(D).The four habitat types are ranked as riparian>woodland>old-field>farmland in descending order of Patrick richness index,Shannon-Wiener diversity index and Simpson diversity index values.The farmland system has the highest dominant index and evenness index values.