Evolutionary Prediction of Soil Loss from Observed Rainstorm Parameters in an Erosion Watershed Using Genetic Programming

Table 3

Statistical analysis of collected database.

	Rainfall amount (P)	Kinetic energy (EK)	Rainfall intensity (I)	Gully head advance (E)	Soil detachment (D)	Factored soil detachment (Df)	Runoff (R)	Runoff rate (Rr)	Soil loss (L)
	mm	J/m^2/mm	mm/hr	m	g/m^2	g/m^2	Litre	m^3/s	kg/m^2
Training set
Max.	5.1	14.0	2.0	37.3	4.6	4.7	14.0	3.2	8.5
Min.	37.7	38.8	66.8	55.7	20.3	20.7	65.0	16.6	110.0
Avg.	16.5	30.5	34.8	46.4	11.4	11.6	42.5	10.1	44.5
SD	7.9	6.0	18.8	4.5	4.8	4.9	14.0	3.9	24.7
Var.	0.5	0.2	0.5	0.1	0.4	0.4	0.3	0.4	0.6
Validation set
Max.	8.0	22.7	8.6	40.8	2.2	2.2	3.2	5.0	10.0
Min.	46.0	39.7	61.0	57.9	19.2	19.5	69.5	17.6	100.0
Avg.	23.1	33.5	30.0	49.4	8.0	8.1	45.5	11.4	45.9
SD	12.4	4.7	15.3	5.2	4.2	4.3	18.4	3.8	25.7
Var.	0.5	0.1	0.5	0.1	0.5	0.5	0.4	0.3	0.6