The effect of range land change to agriculture and forest park on some soil physicochemical characteristics

The purpose of this research was investigation of soil physicochemical and particle distribution in three agricultures, rangeland and forest park land use in two surface (0-15 cm) and subsurface (15-30 cm) depths in Oshtorninan city on the Lorestan province. Soil sampling was done in 45 points in three land use. Some soil physico-chemical properties were determined in laboratory. This experiment was arranged in a factorial manner. The results showed that the change of rangeland use to agriculture has resulted in a decrease in clay content, cation exchange capacity, soil carbon, nitrogen and soil particle size. Changing the land use of pasture to forest park has led to an increase in the amount of clay, silt and soil acidity. Mean comparison showed that there was no significant difference between bulk density and electrical conductivity in the three land uses (p ≤ 0.01). Analysis of the data showed that the soil cation exchange capacity, organic carbon, clay and silt content in three land uses and two depths were significantly different (p ≤ 0.01). Land use factor also showed a significant different on soil sand and lime percentage (p ≤ 0.01). The soil granulation did not change with the conversion of the rangeland in to a forest. Increased organic carbon and soil clay content could be the reason for this. In general, land use change from pasture to agriculture similar to other research is unfavorable, but land use change to forest park has improved clay content, cation exchange capacity and soil organic carbon.