Aboufayed Equations for Evaluation Erodibility Factor (K) of Some Libyan Soil

Abstract

To establish equation for prediction of Libyan soil erodibility factor(K),  samples of the main three types of Libyan soil were collected. The soil erodibilty factor was evaluated in indirect way by measuring  the soil erosion rate and using universal soil loss equation (K=A/RLSCP).  The soil properties related to soil erodibility were also measured  to establish the equation  for prediction of  Libyan soil erodibility factor  upon it's soil properties. The simple linear regression  were used to determinate  the first soil property in the model which has the highest correlation coefficient (R) between soil erodiblity factor as a dependent variable and soil properties as independent variables. Multiple linear regression analyses were used to determine the soil properties variables which have significant effect on the prediction of the equation (1) with high determination coefficient (R²=83.5%)  as  shown in the following  equation:

(K=-1.0+0.02(vfs) +0.06(fs)+0.1(Pd))…………..................................………............. (1)

Where (vfs) is the percent of soil content of very fine sand, (fs) is the percent of soil content of fine sand and (Pd) is the soil permeability degree. And an other equation were reached deend on very fine sand and the square of very fine sand with very high determination coefficient  (R²=83.7%)as shown by equation (2):

K=-0.07-0.005(vfs%)+0.00025(vfs%)²…………............……….(2)          

The equations is known as Aboufayed equations regarding to the researcher hard work to reach these equations,