بررسي رابطه بين خصوصيات فيزيكوشيميايي خاك و پوشش گياهي در خاك هاي شور و گچي مراتع قشلاقي اشتهارد

Soil-vegetation relationships in saliferous and gypsiferous soils in winter rangelands (Eshtehard)

Saliferous and gypsiferous aridisols are among the vast extension soils of rangelands in arid and semi-arid regions of Iran. Vegetation cover with low density is representative of special physicochemical characteristics of these soils. The aim of the present study was to identify gypsophilous and halophilic plants and also to investigate plants distribution related to physicochemical characteristics of saliferous and gypsiferous in Eshtehard winter rangelands. Vegetation sampling was conducted in the key area based on randomized-systematic pattern, and data including canopy cover and density along transects in each plot were determined. After determination of plant types, the soil profiles were excavated and soil samples collected. Based on the standard methods, physicochemical characteristics, including soil texture, electrical conductivity in saturated extract, soil reaction, organic carbon content, gypsum and equivalent calcium carbonate percentage, soluble anions and cat ions were determined. Multivariate method of principal component analysis (PCA) was used to analyze the collected data. The results showed that the vegetation distribution pattern was mainly related to soil characteristics such as salinity, texture, chloride, soil reaction, gypsum and gravel percentage.