Ejtehadi H, Soltani R, Zahedi Pour H
Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran.
Pak J Biol Sci. 2007 Oct 15;10(20):3683-7. doi: 10.3923/pjbs.2007.3683.3687.
The aim was to examine and document several aspects of numerical diversity such as species richness, species diversity and evenness and to compare diversity in different slope aspects of the area by using numerical and parametric methods. About 193 quadrats of 4 m2 were located according to the nature of vegetation. Species composition and their abundance were recorded in a two-year period (2005 to 2006). The result of field investigation was collecting and identifying of the total 225 plant species belonging to 154 genera and 37 families. The abundance data were subjected to analyses by specific diversity packages to characterize and obtain numerical indices (Shannon, Simpson, Brillouin, McIntosh, etc.,) and parametric families of species diversity. Numerical indices were calculated and documented for monitoring purposes. The results of diversity in main slope aspects (N, S, E, W) showed higher species richness and species diversity indices in the north aspect than in the others but it was not true with evenness indices. About 30 species such as Acanthophyllum glandulosum, Acroptilon repens, Alcea tiliacea, Bromus sericeous, Astragalus turbinatus, Centaurea balsamita etc., were detected exclusively in the north aspect. This can be important in reducing the evenness. Diversity comparing by using rank-abundance plot as well as diversity ordering of Hill, Renyi and Patil and Taillie confirmed high species diversity in the north yet the result of ANOVA showed no significant differences in the four aspects. The result of diversity based on the models revealed that the whole area, the south and the west aspects follow lognormal distribution, north aspect follows logarithmic whereas the east follows both lognormal and logarithmic distribution. In other word, a shift from being lognormal to logarithmic model was observed in the east aspect.
目的是研究和记录数值多样性的几个方面,如物种丰富度、物种多样性和均匀度,并通过数值和参数方法比较该地区不同坡面的多样性。根据植被性质设置了约193个4平方米的样方。在两年期间(2005年至2006年)记录了物种组成及其丰度。实地调查结果是收集并鉴定了总共225种植物,隶属于154属37科。对丰度数据采用特定的多样性软件包进行分析,以表征并获得数值指数(香农指数、辛普森指数、布里渊指数、麦金托什指数等)以及物种多样性的参数族。为监测目的计算并记录了数值指数。主要坡面(北、南、东、西)的多样性结果显示,北面的物种丰富度和物种多样性指数高于其他坡面,但均匀度指数并非如此。约30种植物,如腺毛棘豆、顶羽菊、蜀葵、绢毛雀麦、陀螺状黄芪、香矢车菊等,仅在北面被发现。这在降低均匀度方面可能很重要。通过秩 - 丰度图进行的多样性比较以及希尔、雷尼和帕蒂尔与泰利的多样性排序证实了北面具有较高的物种多样性,但方差分析结果表明这四个坡面没有显著差异。基于模型的多样性结果显示,整个区域、南面和西面遵循对数正态分布,北面遵循对数分布,而东面既遵循对数正态分布又遵循对数分布。换句话说,在东面观察到了从对数正态模型到对数模型的转变。