Using the USLE and the Desmet and Govers method for calculating L will produce erosion predictions which will not vary with the antecedent moisture conditions. The USLE-M predicts that erosion will vary if antecedent moisture conditions vary. For further information see Kinnell, P.I.A.(2000). AGNPS-UM: Applying the USLE-M within the Agricultural Non Point Source Pollution Model. Environmental Modelling and Software 15, 331-341. PDF file available from Literature page