The Effect of Altitude and Aspect on Rangeland Plant Diversity (Case Study: Dashte Zahab, Kermanshah, Iran)

Document Type: Research and Full Length Article


1 Dept. Forest and Rangeland, Ilam University.

2 Dept. Forestry, Urmia University,

3 Combat Desertification, Ilam University


Recognizing the herbaceous plant species diversity could use as an important
indicator applied for the rangeland and forests management. Considering the presence of
vegetation and animal husbandry in Zagros region, Iran, being aware of the diversity and
richness of plant species is necessary to management or the destructed vegetation
restoration. In order to study the effect of aspect and elevation on species diversity of
herbaceous plants 160 four m2 quadrates were sampled via transect method in the Dasht e
Zahab in Kermanshah, Iran. In each quadrate a list herbaceous species plants, altitude and
aspect were recorded. After the inventory, the plant diversity indices were calculated and
compared in three elevation classes (low: <800 m, moderate: 800 to 1200 m and high:
>1200 m) and four aspect classes (North, South, East and West) using Shannon-Wiener
diversity and Margalef richness indices. One-way ANOVA was used to investigate the
effect of independent variables (altitude and aspects) on dependent variable (species
diversity and richness). The results showed a significant effect of aspect and altitude on the
diversity and richness of herbaceous plants (P<0.05). The maximum and minimum
diversity and species richness were observed on the northern aspect coupled with middle
elevation and on the southern aspect with low elevation, respectively.