Faculty of New Sciences and Technologies, University of TehranIranian journal of Ecohydrology2423-60986120190321Comparative Analysis of soil Erodibility Factor in Shazand WatershedComparative Analysis of soil Erodibility Factor in Shazand Watershed1531637029510.22059/ije.2018.269592.985FAMahboobehKiani HarcheganiPostdoctoral Fellow, Department of Watershed Management Engineering, Faculty of Natural Resources Tarbiat Modares University, Noor, Iran0000-0003-1075-1169Seyed HamidrezaSadeghiProfessor, Department of Watershed Management Engineering, Faculty of Natural Resources Tarbiat Modares University, Noor, Iran0000-0002-5419-8062SamerehFalahatkarAssistant Professor, Department of Environment Engineering, Faculty of Natural Resources Tarbiat Modares University, Noor, IranJournal Article20180823Soil erosion is a serious environmental, social and economic problem. It not only causes severe land degradation and soil loss, but also threatens the stability and health of the society and, in general, its sustainable development. Soil erosion is related to different soil characteristics, measurements and its calculations. The soil erodibility factor (K) is one of the important factors in determining soil erosion. Different methods have been developed to determine of K using empirical models or field measurements. Currently, widely used equations that estimate K, on the basis of soil basic properties, include soil texture, organic matter, structure, and permeability. Therefore, in this study, three commonly equations were used to estimate of K in Shazand watershed such as Wischmeier and Smith (1978), Romkens et al. (1986), Torri et al. (1997 and 2002) with K<sub>1</sub>, K<sub>2</sub> and K<sub>3</sub>, respectively. In this regard, field sampling was done at 140 points of Shazand watershed with an area of 1740 km<sup>2</sup>. The Shazand watershed has limestone with low organic matter and medium texture. In the following, one-way ANOVA was used to analyze of K<sub>1</sub>, K<sub>2</sub> and K<sub>3</sub> results under the impact of different slope and elevation classes and different land uses, as well as Kriging's method for generation their spatial pattern. The results of one-way ANOVA showed that K<sub>1</sub>, K<sub>2</sub> and K<sub>3</sub> influenced by different slope and elevation classes with a significant difference (P< 0.05). But they had no significant difference (P ≤ 0.318) in different land use. Also, the average of K<sub>1</sub>, K<sub>2</sub> and K<sub>3</sub> was calculated to be 0.054, 0.039 and 0.035 t ha h ha<sup>-1</sup> MJ<sup>-1</sup> mm<sup>-1</sup> respectively.Soil erosion is a serious environmental, social and economic problem. It not only causes severe land degradation and soil loss, but also threatens the stability and health of the society and, in general, its sustainable development. Soil erosion is related to different soil characteristics, measurements and its calculations. The soil erodibility factor (K) is one of the important factors in determining soil erosion. Different methods have been developed to determine of K using empirical models or field measurements. Currently, widely used equations that estimate K, on the basis of soil basic properties, include soil texture, organic matter, structure, and permeability. Therefore, in this study, three commonly equations were used to estimate of K in Shazand watershed such as Wischmeier and Smith (1978), Romkens et al. (1986), Torri et al. (1997 and 2002) with K<sub>1</sub>, K<sub>2</sub> and K<sub>3</sub>, respectively. In this regard, field sampling was done at 140 points of Shazand watershed with an area of 1740 km<sup>2</sup>. The Shazand watershed has limestone with low organic matter and medium texture. In the following, one-way ANOVA was used to analyze of K<sub>1</sub>, K<sub>2</sub> and K<sub>3</sub> results under the impact of different slope and elevation classes and different land uses, as well as Kriging's method for generation their spatial pattern. The results of one-way ANOVA showed that K<sub>1</sub>, K<sub>2</sub> and K<sub>3</sub> influenced by different slope and elevation classes with a significant difference (P< 0.05). But they had no significant difference (P ≤ 0.318) in different land use. Also, the average of K<sub>1</sub>, K<sub>2</sub> and K<sub>3</sub> was calculated to be 0.054, 0.039 and 0.035 t ha h ha<sup>-1</sup> MJ<sup>-1</sup> mm<sup>-1</sup> respectively.https://ije.ut.ac.ir/article_70295_08942a30e46708a0d931d0c1c13e573f.pdf