Relationship Between Ecological Species Groups and Environmental Factors in Fandoghlou Rangelands of Ardabil, Iran

This study was performed to investigate the relationship between ecological species groups and environmental factors in Fandoghlou rangelands of Ardabil province in the northwest of Iran, assuming that plant species distribution has been correlated with various of complex environmental gradients.

Data were collected from 180 sampling plots (1m2) in an area of 3.27km2 using the systematic-random method. In each plot, environmental factors (topography, climate, and soil variables) and the percent of vegetation cover for each species were recorded. TWINSPAN method and Canonical Correspondence Analysis (CCA) were used to define ecological species groups and determine the relationship between ecological species groups and environmental factors, respectively.

Results of using TWINSPAN for 180 plots classified rangeland communities into three groups. The first group contained 110 plots, the second group 40 plots, and the third group 30 plots. Using ISA, vegetation species groups in the first group contained 8 species, the second group 11 species, and the third group 8 species. In each group, the name of the species with the highest index value was selected as the groupchr('39')s name. Thus using CCA, the group of Trifolium pratense had a relation with aspect, slope, organic matter, magnesium, temperature, and volumetric soil moisture. The Leucanthemum vulgare was related to phosphorus, elevation, lime, sand, clay, and potassium. The group of Trifolium repense had a relation with pH, electrical conductivity, calcium, diffusible clay, temperature, silt, and sodium. The factors of diffusible clay and electrical conductivity with the first CCA axis and potassium and phosphorus factors with the second CCA axis had the strongest correlations.

Using the results of this study, we can evaluate the habitat conditions and vegetation quality of Fandoghlou rangelands. Moreover, used high-quality rangeland species such as Trifolium to counteract the spread of invasive species such as Leucanthemum vulgare.