The Effect of Changing Land Uses on Physical and Chemical Properties of Soil in Two Rangelands and Their Adjoining Agricultural Fields (Case Study: Damavand Region)

The change in the use of rangelands along with the destruction of soil structure has had a detrimental effect on the soil characteristics of these lands and is considered as one of the most important factors in the degradation of physical-chemical properties of the soil. Therefore, in this research, the effects of rangeland use change on soil characteristics of Damavand area were investigated. In each of the two sites, 50 sampling sites of agronomic land and 30 sampling sites from rangelands were selected for examination after determining the network of sampling points and the minimum decision area. Sampling from soil at depths of 0-30 cm was performed with three replications in each sample. The studied characteristics were measured using independent t-test and their mean differences were investigated. The results showed that there is a significant difference between the amounts of gravel, clay, organic matter, total nitrogen and calcium carbonate content in pasture and crops, at 99% confidence interval. Therefore, a change in the use of rangelands to arable lands reduces organic carbon (0.3), total nitrogen (0.66) and clay (12.5) and increases the amount of gravel (18.54%) and calcium carbonate (12.68%) in the soil. In other words, changing the use has reduced the fertility and resulted in the degradation of pasture land in Damavand area.