International Symposium on
Drylands Ecology and Human Security

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Documenting and Comparing Plant Species Diversity by Using Numerical and Parametric Methods in Khaje Kalat, Northeastern Iran

H. Ejtehadi 1, R. Soltani 1 and H. Zahedi Pour 2

1Dept. of Biology, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran

2Research Center of Agriculture and Natural Resources, Arak, Iran


Forests and rangelands are ecosystems containing great genetic resources and plant species diversity that have profound effects on their stability. Study of floristic composition and species diversity is crucial for conservation, managing ecosystems and maintaining biodiversity. Therefore a study was carried out in Pistacia forest of Khaje-Kalat in the North-East of Iran, located between geographical position of 36º 35´ N and 60º 30´ E with the mean annual precipitation and temperature of about 255 mm and 18ºC, respectively. 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 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. The result of field investigation was collecting and identifying of the total 225 plant species belonging to 154 genera and 37 families. The collected 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 (more detail in the paper). The results of diversity in main slope aspects (N, S, E, W) showed a higher species richness and species diversity indices in the north aspect than in the others but it is not true with evenness indices. About 30 species such as Acanthophyllum glandulosum, Acroptilon repens, Alcea tiliacea, Bromus sericeous, Astragalus turbinatus, Centaurea balsamita etc., were just presented 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 & 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 area, in general, 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.

Keywords: Species diversity, Numerical indices, Parametric methods, Khaje Kalat, NE Iran