Determination of soil erodibility factor using fuzzy rule base system

Soil erodibility factor (K-factor) is one of the most important factors on USLE model. This factor is calculated on the basis of some soil properties such as soil texture (percentage of soil particles less than 0.1 mm and percentage of coarse sand particles larger than 0.1 mm), soil organic matter, soil structure and basic permeability of the soil profile. So far, various methods have been introduced for the measurement of K-factor. The objective of this research is to determine the soil erodibility factor using fuzzy rule base system. Sixty samples were collected from sixty homogenous units based on the Wischmeier's nomograph method. After generating the fuzzy rules and calculating the soil erodibility factor, the results were compared with those of Wischmeier's nomograph method. The results showed that the values of K-factor calculated by the fuzzy system are quite close to the values obtained by the USLE model and therefore, the fuzzy rule base model is introduced as the most suitable site selection strategy for determining soil erodibility factor.