Document Type : Research Paper

Authors

university of kurdistan

Abstract

Knowledge of species distribution patterns in each area is the basis of vegetation measurement. Determining the species distribution pattern helps us select the appropriate methods for measuring quantitative properties such as species density and abundance. In order to study the distribution pattern of three shrub specie, a part of Kurdistan rangelands was selected as the study area. A random systematic sampling method was used along four transects of 300 meters. The first point on each transect was randomly selected and the rest (14 points) were selected along each of the transects with 20-meter intervals from each other. In each vegetation type, criteria such as density and abundance were measured in plots, and the distance from a random point to the nearest plant and to the nearest neighbors was determined along the transects. In addition, the distribution pattern of Acantholimon bracteatum, Astragalus gossypinus  and Acanthophyllum mucronatum was determined using distance indices (Eberhardt, Hopkins, Johnson and Zimmer) and the quadrate indices (Green, Morisitas index, Morisitas standard, and Lioyd). The results of analysis showed that the distance indices had more accuracy than quadrate indices with the same performance.

Keywords

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