Identification of Effective Chemical Factors on Soil Resistance with Discriminant Analysis to Stepwise Method (Case Study Marls of Sorkheh basin)

Marl units with high contents of soluble salts are highly susceptible to erosion. These units produce and enter high amounts of sediment to Sorkhe artificial recharging system every year. Thus, identification of effective agents on susceptibility to erosion of marls is an essential subject. Statistical methods to determine effective factors is based on mean comparison and correlation matrix between data. The correlation matrix tables are very large and complex because so many variables are involved. Therefore, determining main variable and amount of their effect and also relationship between erosion groups is not possible with high accuracy. The aim of this study, is to determine main chemical variables on erosion by Discriminate Analysis and separating increaser and decreaser factors in erosion using SPSS software. The results showed that low rate of erosion in low to moderate surface erosion group (1) and severe surface erosion group (3) is due to TNV, HCO3 and OC correlation between two mentioned groups. On the other hand, high level of erosion in rill erosion group (2) is due to no relation with variables of groups 1 and 3 and high values of CaSO4 and SO4. As well as, atterberg limits have positive correlation with reduction erosion factors. Then by using method we can determine the effective factors fast and accurately.