Distribution behaviour of common plant species along physiographic gradients in two wadi beds of Southern Sinai

Abstract

This study is an analysis of the relationships between the distribution of common plant species in the beds of Wadi El-Sheikh and Wadi Saal near Saint Katherina area in southern Sinai, and variations in altitude, gravel percentage and soil texture. The absolute density of eight perennials and the presence of nine annuals were estimated in 86 stands using 100, 2 m × 2 m quadrats in each. Altitude and the percentages of gravel, sand, silt and clay were determined in each stand. The perennials were more sensitive than annuals to variations in these physiographic factors. The notable changes in the abundance of perennials along their gradients indicated that the vegetation in the study area can be characterized into discrete units. The distribution of perennials was more related to altitude and the percentage of gravel rather than to the percentages of sand, silt and clay.