Investigation of rain fed perennial range plant instead of annual species for ecological control of soil erosion

One of the most important waysto decrease surface evorsion and increase forgie production is cultration of When we cultivate corns and we have not any good yields we can change the corn species with perennial range species. It causes to decrease surface erosion and increase forage production. The goal of this study is assessing of unsuccessful reasons in forage rain fed cultivation of Onobrychis viciaefolia.This study was down in 12 stations in Semirom and Chadegan. At first we had permanent plot in every stage and the number of heaving sainfoin was noted. In every station was prepared a soil profile with 1*1*1.5 meter and in laboratory growing form of sainfoin was studied. Age of plants and physical and chemical characteristic soil and clay mineral were determined. Then clay minerals were analyzed by X-Ray diffraction. Results show that soil has expansion clay minerals 2:1. That after raining in cold season, water and snow water between ingredient was heaved and cause to expand soil. This expantion cause to damage soil granule and increase soil erosion. Finally this expansion cause to go up the plant root and cut.