Determining the type of relationship between the erosion and runoff simultaneous threshold with soil physical properties

Then, sampling of erosion and runoff threshold in 6 points with 3 replicates and in different rainfall intensities of 0.75, 1 and 1.25 mm/min in three land uses of the range, residential area and agricultural lands with the help of the rain simulator was done. In addition, the same number of runoff and erosion threshold samples, sampling of the soil physical properties such as clay, silt, sand, very fine sand and moisture content was done. I The results showed that in Gachsaran Formation and in all three rangeland, agricultural and residential land uses and in all three intensities of 0.75, 1 and 1.25 mm/min, very fine soil sand in eight cases had the opposite relationship and in one case had a direct relationship with the erosion and runoff simultaneous threshold and soil clay had the opposite relationship in two cases and had a direct relationship in seven cases and soil silt had the opposite relationship in four cases and had a direct relationship in five cases. Soil sand in six cases showed the opposite relationship and in two cases showed a direct relationship and in one case did not show a relationship, and soil moisture in seven cases showed an inverse relationship and in two cases showed a direct relationship with erosion and runoff simultaneous threshold.