International Symposium on
Drylands Ecology and Human Security
Predicting the Geographical Distribution of Plant Species in Poshtkouh Rangelands of Yazd Province-Iran
M. A. Zare Chahouki1, M. Jafari, H. Azarnivand, M. Shafizadeh
Faculty of Natural Resources, Tehran University, Karaj, Iran
The aim of this research was to study the relationships between the occurrence of plant species and environmental factors and provide a predictive habitat model for each plant species in Poshtkoh rangelands of Yazd province. After the delineation of the study area, sampling was conducted using randomized-systematic method. Plant species data such as: presence or not, density, and percent cover were collected for each plot. The topographic conditions were also recorded for the plot areas. Soil samples were taken at depths of 0-30 and 30-60 cm in each plot. The measured soil variables included texture, lime, saturation moisture, gypsum, acidity (pH), ECe and SAR. Logistic regression technique was used to analyze the data. The results showed that the vegetation distribution is mainly related to soil characteristics such as EC, saturation moisture, gypsum, gravel and lime. The presence of A. sieberi was inversely related with EC. D. ammoniacum was negatively related with saturation moisture, gravel, and lime, while the presence of Ep.st-Zy.eu was positively related with gypsum.
Keywords: Logistic regression, Environmental factors, Plant species, Artemisia sieberi, Dorema ammoniacum, Ephedra strobilacea, Zygopyllum eurypterum