The generally accepted maximum limit of soil loss or TSL value is 112 Mg ha–1 year–1 (Wishmeier and Smith, 1978). Refer to the following link

https://www.agroengineering.org/index.php/jae/article/view/560/572

Even though there is a reference maximum limit of soil loss as quoted by Prof Samir Ismail, however, the value for modeling is region dependent and sensitive. The Universal Soil Loss Model (IKLSCP), when applied to compute regional losses, the kinetic energy model applied to obtain E.I30, depends on so many environmental indices, some of which are regional

112 Mg ha–1 year–1 in Tonne ha-1 year -1 = ?

Is not easy to get EI30, what is the best formula to use annual rainfall value? any suggestion ?

There are not less than two known models universally accepted to compute Erosive Index for the thirty minutes rainfall intenity (E.I30). Refer to any standard water resources engineering and conservation text

Dear Abdul Rahman Mahmud

A paper is attached. It can be useful for your question.

Thank you so much

Hi everybody,

Dear Abdul Rahman

Due to lack of rainfall intensity data in many regions I think for calculating the R factor ( ranifall erosivity) you must do follwing steps:

1) caculating Fournier Index (Nalder and Wein, 1998).

F= sum of pi*2 (i=1.....12)/P

* is piwer

pi is average of monthly rainfall (mm).

P is average of annual rainfall (mm).

2) If the F index was less than 55 (mm) you must use the below equation:

R-factor= ( 0.07397 × F*1.847)/ 17.2 (Renard & Freimund, 1994)

* is power

3) If F index was more than 55 (mm) or equal to 55 (mm) you must use the below equation:

R-factor= (95.77 - 6.081×F + 0.4770 × F*2)/ 17.2 (Renard & Freimund, 1994).

* is power

Finally after calculating the R factor for each station then you can use interpolation methods (such as IDW) to create a spatial image of R factor.

Warm regards

Bijan