Estimation of infiltration rate from soil properties using regression model for cultivated land

Figures & data

Figure 1. Study area map (marked).

Table 1. Location of 25 stations used in the field measurement of infiltration rate.

Station	Latitude °N	Longitude °E	Elevation (m)
P1	27°17.456’	88°35.614’	861
P2	27°17.454’	88°35.608’	862
P4	27°17.459’	88°35.606’	865
P5	27°17.465’	88°35.611’	864
P8	27°17.468’	88°35.599’	865
P9	27°17.474’	88°35.594’	864
P10	27°17.472’	88°35.595’	865
A1	27°17.481’	88°35.626’	848
A2	27°17.486’	88°35.625’	846
A4	27°17.499’	88°35.635’	843
B1	27°17.485	88°35.623’	846
B2	27°17.499’	88°35.622’	847
B3	27°17.493’	88°35.625	846
B4	27°17.496’	88°35.629	845
C1	27°17.491’	88°35.616’	846
C2	27°17.492’	88°35.620’	846
C3	27°17.495’	88°35.622’	845
C4	27°17.503’	88°35.623’	844
D1	27°17.491’	88°35.610’	845
D2	27°17.489’	88°35.610’	844
D3	27°17.495’	88°35.614’	843
D4	27°17.508’	88°35.619’	842
E1	27°17.493’	88°35.606’	845
E2	27°17.495’	88°35.609’	844
E4	27°17.506’	88°35.618’	843

Table 2. Physical properties collected soil samples.

Station	Sand	Silt	Clay	BD	PD	MC	OC	Textural class
P1	77.00	9.66	13.34	1.56	2.32	28.22	0.301	Sandy loam
P2	74.00	11.25	14.75	1.569	2.2	28.93	0.2936	Sandy loam
P4	72.40	9.60	18.00	1.674	2.318	28.17	0.2802	Sandy loam
P5	80.10	11.26	8.64	1.489	2.372	24.67	0.333	Loamy sand
P8	76.88	13.97	9.15	1.62	2.217	26.91	0.3184	Sandy loam
P9	68.76	16.21	15.03	1.46	2.428	21.99	0.3328	Sandy loam
P10	71.16	16.22	12.62	1.677	2.5	27.83	0.3433	Sandy loam
A1	68.63	20.22	11.15	1.716	2.318	24.58	0.3318	Sandy loam
A2	82.27	11.33	6.40	1.616	2	21.96	0.3439	Loamy sand
A4	82.28	7.36	10.36	1.657	2.702	14.56	0.3432	Loamy sand
B1	62.93	18.00	19.07	1.59	2.564	28.4	0.3599	Sandy loam
B2	79.88	14.03	6.09	1.412	2.564	22.34	0.3606	Sandy loam
B3	70.40	12.56	17.04	1.648	2.702	22.65	0.3606	Sandy loam
B4	79.21	9.64	11.15	1.648	2.702	13.96	0.3574	Sandy loam
C1	72.00	17.67	10.33	1.716	2.564	27.33	0.3623	Sandy loam
C2	69.93	18.33	11.74	1.613	2.857	25.7	0.3512	Sandy loam
C3	69.35	20.25	10.40	1.508	2.778	22.77	0.3498	Sandy loam
C4	80.60	10.67	8.73	1.432	2.702	16.67	0.3555	Loamy sand
D1	84.00	10.14	5.86	1.677	3.03	28.46	0.3525	Loamy sand
D2	71.19	19.96	8.85	1.579	2.702	27.48	0.3587	Sandy loam
D3	67.19	19.14	13.67	1.465	2.78	24.99	0.361	Sandy loam
D4	74.50	13.60	11.90	1.445	2.702	18.96	0.358	Sandy loam
E1	70.21	17.17	12.62	1.584	2.857	26.03	0.3257	Sandy loam
E2	71.16	15.89	12.95	1.479	2.631	27.36	0.3619	Sandy loam
E4	82.23	12.44	5.33	1.503	2.63	20.28	0.3523	Loamy sand

Note: Sand, Silt, Clay, MC and OC are in % and BD, PD, are in g/cm³

Table 3. Descriptive statistics of measured soil properties.

Soil property	Max	Min	Mean	SD	CV
Sand (%)	84	62.93	74.33	4.90	6.60
Silt (%)	20.25	7.36	14.26	3.37	23.65
Clay (%)	19.07	5.33	11.41	2.87	25.14
BD (g/cm^3)	1.716	1.412	1.57	0.08	5.01
PD (g/cm^3)	3.03	2	2.57	0.19	7.55
MC (%)	28.93	13.96	24.05	3.55	14.75
OC (%)	0.36	0.28	0.34	0.018	5.12

Note: Maximum value (Max); Minimum value (Min); Mean value (Mean); Standard deviation (SD); Coefficient of variation (CV)

Table 4. RMSE values between observed IR and estimated IR based no number (n = 3, 4, 5, 6, 7) of parameters.

Station	BIR	Est3P	RMSE3P	Est4P	RMSE4P	Est5P	RMSE5P	Est6P	RMSE6P	Est7P	RMSE7P
P1	4.80	6.36	1.56	6.75	1.95	7.81	3.01	7.22	2.48	7.07	2.27
P2	4.41	4.69	0.28	5.01	0.60	6.97	2.56	5.94	2.21	5.80	1.39
P4	4.20	2.48	1.72	1.76	2.44	1.29	2.91	0.88	1.88	0.62	3.58
P5	11.70	9.80	1.90	10.75	0.95	11.15	0.55	10.52	9.33	10.51	1.19
P8	8.10	8.54	0.44	7.88	0.22	7.95	0.15	6.78	5.88	6.70	1.40
P9	2.40	3.89	1.49	5.36	2.96	3.32	0.92	2.81	0.03	2.69	0.29
P10	3.30	3.22	0.08	2.11	1.19	2.62	0.68	2.49	0.80	2.63	0.67
A1	3.00	4.92	1.92	3.08	0.08	3.07	0.07	2.10	0.68	2.05	0.95
A2	6.30	11.65	5.35	10.96	4.66	10.17	3.87	8.33	4.30	8.54	2.24
A4	2.40	9.57	7.17	8.69	6.29	6.18	3.78	6.97	0.30	6.98	4.58
B1	0.30	−1.01	1.31	−0.86	1.16	−1.15	1.45	−1.10	2.26	−0.89	1.19
B2	13.80	11.08	2.72	12.75	1.05	12.97	0.83	12.78	11.24	12.83	0.97
B3	3.00	2.37	0.63	1.84	1.16	1.45	1.55	2.17	0.30	2.39	0.61
B4	10.32	8.19	2.13	7.41	2.91	7.42	2.90	8.11	7.62	8.27	2.05
C1	3.30	6.83	3.53	4.97	1.67	4.43	1.13	4.35	0.74	4.45	1.15
C2	3.00	5.02	2.02	4.49	1.49	3.20	0.20	4.07	0.14	3.95	0.95
C3	2.70	2.79	0.09	3.01	0.31	2.75	0.05	2.77	0.08	2.74	0.04
C4	10.80	9.91	0.89	11.56	0.76	8.89	1.91	9.39	8.10	9.38	1.42
D1	16.80	12.93	3.87	11.47	5.33	13.71	3.09	15.33	13.77	15.25	1.55
D2	7.20	6.86	0.34	6.53	0.67	6.84	0.36	7.01	4.50	6.98	0.22
D3	4.80	3.15	1.65	4.48	0.32	3.78	1.02	4.31	2.02	4.31	0.49
D4	8.67	6.35	2.32	7.95	0.72	9.43	0.76	9.86	5.97	9.96	1.29
E1	3.00	4.57	1.57	4.44	1.44	5.36	2.36	6.24	0.14	5.98	2.98
E2	7.50	4.75	2.75	5.95	1.55	8.73	1.23	8.86	4.87	9.03	1.53
E4	15.30	12.21	3.09	12.78	2.52	12.78	2.52	12.90	12.67	12.88	2.42

Note: Basic IR (cm)/Observed IR, BIR;Estimated n Parameter, Est_np where n = 3,4,5,6,7

Figure 2. Measured infiltration rate versus estimated infiltration rate.

Figure 3. Measured infiltration rate versus estimated infiltration rate.

Figure 4. Measured infiltration rate versus estimated infiltration rate.

Figure 5. Measured infiltration rate versus estimated infiltration rate using equation 4.

Figure 6. Measured infiltration rate versus estimated infiltration rate.

Figure 7. Relation between sand and measured infiltration rate.

Figure 8. Relation between silt and measured infiltration rate.

Figure 9. Relation between clay and measured infiltration rate.

Figure 10. Relation between bulk density and measured infiltration rate.

Figure 11. Relation between moisture content and measured infiltration rate.

Figure 12. Relation between particle density and measured infiltration rate.

Figure 13. Relation between organic carbon and measured infiltration rate.

Table 5. Correlation between dependent and independent variables.

	IR (cm/h)	Sand	Silt	Clay	BD	PD	MC	OC
IR (cm/h)	1.00
Sand (%)	0.75	1.00
Silt (%)	−0.41	−0.77	1.00
Clay (%)	−0.73	−0.74	0.14	1.00
BD (g/cm^3)	−0.33	−0.06	−0.05	0.15	1.00
PD (g/cm^3)	0.18	−0.08	0.21	−0.09	−0.11	1.00
MC (%)	−0.22	−0.44	0.37	0.29	0.24	−0.19	1.00
OC (%)	0.22	−0.03	0.34	−0.32	−0.21	0.58	−0.36	1.00

Note: Sand, Silt, Clay, MC and OC are in % and BD, PD, are in g/cm³

Table 6. The statistical validation of observed vs. estimated infiltration rate.

Basic IR (cm)	5.8	2.91	4.2	7.52	7.1	3.1	3.8	3.08	6.8	2.5	0.3	10.5	3	7.32	3.8
Estimated IR	7.07	4.8	3.92	9.75	5.70	2.69	2.63	2.55	7.54	2.98	0.29	11.83	2.39	8.27	4.45
Statistical test								Value
RMSE								1.103
R-RMSE								0.244
MAE								0.342
NRMSE								0.231
MBE								−0.342
MAPE								0.477
D								0.9993
RMSE%								1.538
NSE								26.332
RSE = RMSE/SD in observd								0.419
IR (average index ratio)								1.072
PE (% Error)								7.154
Sd^2								1.136
R^2								0.89
p (at 95%)								0.099
Multi R								0.95
Adj. R								0.890
Standard error								0.870

Figure 14. Plot of observed vs. estimated infiltration rate.