陕西洛河流域不同生境蝗虫的群落结构

The diversity of grasshopper community in different habitats in Luo River Pregion, Shanxi

应用种-多度分布模型、多样性指数、相似性分析、主成分(PCA)分析及多元逐步回归等方法比较了洛河流域不同生境的蝗虫群落结构。结果显示:洛河流域各生境的蝗虫分布基本上服从Preston对数正态分布,其中以森林拟合的最好。各多样性指数的变化趋势均为森林>森林草原>河滩和农田>典型草原。在相似性分析中,典型草原、森林草原和森林这3种生境相似性很高,而河滩和农田则是完全不同的另一种生境。对各生境植被因素和蝗虫群落所进行的主成分分析,结果非常理想,两维主成分的累计方差贡献率分别达到了92.558%和78.566%。通过多元逐步回归发现,影响蝗虫种类和数量变化的植被因有草本植物高度多样性、树木盖度、豆科优势度、禾本科优势度和其他科优势度等。

The structure of grasshopper community in different environment in Luo River region was compared using species-abundance model, diversity index, similarity analysis, principal component analysis and stepwise regression. The results showed that the distribution of grasshoppers in different environment basically matches to the Preston＇ s lognormal distribution in which that in forest matches best. The trend of every diversity index is forest 〉 forest and grassland 〉 floodplain and cropland 〉 typical grassland. In the analysis of similarity and clustering, the similarity of typical grassland, forest and grassland and forest is very high, where as floodplain and cropland are completely different environment. The results of PCA analyzing the vegetation factors and grasshoppers community showed, the cumulative percent of two principal components reach 92. 558 % and 78. 566 %, respectively. By stepwise regression analysis, it showed that several vegetation factors, including grass height diversity, tree density, leguminosae dominance degree, gramineae dominance degree and other grass dominance degree, influence the species and numbers of grasshopper.