The study of the effective-environmental factors on distribution of Calligonum eriopodumCase study: dune lands of Qean

Calligonum eriopodum is the only psammophyte shrub in Iran, which was reported from South Korassan. Searching of environmental limitation of the species was the goal of current research that has been done on dune lands around the east direction of the Qaen city in south Khorassan. First of all, the habitat boundary was cleared by field monitoring and GPS recording of points and the species distribution, and then was pointed at map scale 1:50,000. Sampling in inside and outside by using three 1000-meter transects were laid down on the land, and the soil and plant samples were selected using five by five meter plots. The soil samples were taken from the fifth plot in each transects. The water samples were obtained. The t test was done to compare the soil and water samples from two habitats. Results showed that the soil and vegetation conditions were statistically the same inside and outside the habitat. However, EC and TDS of water samples were significantly different two habitat (P-value<0.05). The EC rate of the water resources was less in the inside habitat position than the outside of the species habitat. The water table level (WTL) in the inside limatation in close to the surface was (less than five meters) while it was between twenty five to thirty two meters in the outside land. It can be stated in among environmental factors the WTL and the quality of water resources were the cause of establishing of the species in the dune lands.