Mohammad Mehdi Khalaj - MSc. Student of Desert Management, Faculty of Natural Resources, Yazd University, Yazd, Iran.
Gholamhosein Moradi - Assistant Professor, Faculty of Natural Resources, Yazd University, Yazd, Iran.
Mohammad Ali Hakimzadeh Ardakani - Associate Professor, Faculty of Natural Resources, Yazd University, Yazd, Iran.

Soil variations study is an exciting topic for ecologists. Relationships among the ecosystem ecological variables are very essential for management, restoration, and development of vegetation cover in similar regions. Therefore, research on dry and semi-arid ecosystems is very important for increasing vegetation cover. Hence, the vegetation-environment relationship has always been an essential concept in ecology. To conduct this research, two Suaeda aegyptiaca sites were selected in central Iran (Neyriz) and, three transects were taken in each site. The transects were ۵۰۰ meters long and ۱۰۰ meters far from each other. The plots, area in each site was determined by the minimum surface method using a nested plot technique and area/species curves . Then, to do the same analysis for two sites and achieve greater accuracy, we considered the area of the plots to be greater than the minimum area. Soil samples were collected from ۰–۳۰ and ۳۰–۶۰ cm the depth in each plot. These depths were selected based on depth of plant species roots in the study area and previous researches. XLSTAT program and Principal components analysis (PCA) was used to investigate the main environmental factors related to the variation in Suaeda aegyptiaca distribution. The results showed that the amount of Suaeda aegyptiaca oil had a high correlation with carbon and had a positively correlated with the amount of sand, phosphorus and nitrogen. However, it has a negatively correlates with electrical conductivity(EC), silt percentage, C/N, calcium carbonate and, soil pH.

Suaeda aegyptiaca, Soil factors, medicinal plant, Neyriz