Performance Evaluation of Four-Parameter Models of the Soil-Water Characteristic Curve

Table 3

Model parameter values for various soil textural classes.

Soil type	Model	Soil sample 1				Soil sample 2
		𝜃𝑠	𝜃𝑟	P1	P2	𝜃𝑠	𝜃𝑟	P1	P2
Sand	BC	0.3478	0.0540	1.2740	0.7945	0.4197	0.0246	0.3891	0.3328
	VG	0.3569	0.0591	0.4778	2.1840	0.4362	0.0486	1.5030	1.4840
	LN	0.3606	0.0624	3.2470	1.0170	0.4574	0.0678	2.1460	1.9630
	MG	0.3627	0.0611	1.9120	1.6260	0.4564	0.0641	0.6757	0.8432
Loamy sand	BC	0.3227	0.0650	1.5480	1.5300	0.2996	3.22𝐸−07	0.6394	0.2697
	VG	0.3289	0.0685	0.4861	3.1490	0.2941	0.0530	0.6094	1.5660
	LN	0.3294	0.0713	2.4610	0.6216	0.2976	0.0735	4.2480	1.5190
	MG	0.3308	0.0700	2.3920	2.6570	0.2972	0.0704	1.5940	1.0780
Sandy loam	BC	0.3170	4.85𝐸−07	3.3910	0.1472	0.3760	0.0569	6.2370	0.3708
	VG	0.3144	2.14𝐸−05	0.1303	1.1830	0.3835	0.0788	0.0981	1.5340
	LN	0.3377	0.0521	113.30	3.3450	0.3883	0.1001	29.890	1.6520
	MG	0.3475	0.0430	2.1290	0.4512	0.3915	0.0962	3.3350	0.9795
Silty loam	BC	0.3995	1.43𝐸−05	3.0280	0.1083	0.3874	0.0417	13.670	0.4824
	VG	0.3995	4.13𝐸−05	0.1736	1.1280	0.3953	0.0601	0.0439	1.7030
	LN	0.4114	0.1537	86.940	2.8870	0.3968	0.0787	51.180	1.3300
	MG	0.4194	0.1446	2.3500	0.5241	0.3985	0.0747	4.8500	1.2260
Silt	BC	0.4358	1.73𝐸−07	8.761	0.3027	0.3750	0.0374	17.350	0.4392
	VG	0.4414	3.16𝐸−07	0.0542	1.4060	0.3803	0.0831	0.0266	2.0980
	LN	0.4476	0.0529	70.590	1.8720	0.3790	0.0943	57.900	0.8778
	MG	0.4510	0.0464	3.7360	0.8711	0.3808	0.0927	7.6270	1.8820
Loam	BC	0.4007	2.81𝐸−04	2.1230	0.1795	0.3637	1.05𝐸−09	14.440	0.1330
	VG	0.4151	0.1499	0.2749	1.4650	0.3642	9.13𝐸−06	0.0193	1.2060
	LN	0.4153	0.2049	9.2920	1.4010	0.3714	7.30𝐸−09	1308.0	3.0400
	MG	0.4197	0.1994	2.4790	1.1070	0.3752	1.35𝐸−06	3.9000	0.5485
Sandy clay loam	BC	0.5337	1.13𝐸−10	0.1632	0.0742	0.3030	7.63𝐸−04	7.917	0.0882
	VG	0.5322	2.35𝐸−08	5.0510	1.0760	0.3069	4.56𝐸−05	0.0739	1.1030
	LN	0.5332	1.26𝐸−05	882.40	6.5790	0.3078	0.1642	167.20	2.3470
	MG	0.5337	2.47𝐸−07	1.6910	0.2511	0.3089	0.1657	3.5820	0.7081
Silty clay loam	BC	0.3890	7.50𝐸−08	2.2220	0.0569	0.5300	1.98𝐸−05	4.6970	0.1883
	VG	0.3902	1.06𝐸−06	0.2363	1.0670	0.5488	0.1355	0.1029	1.4110
	LN	0.4070	8.30𝐸−05	11740	6.0330	0.5723	0.1881	31.560	1.8770
	MG	0.4151	0.0019	2.4390	0.2673	0.5838	0.1771	2.8110	0.8148
Clay loam	BC	0.3561	0.0373	9.6590	0.0564	0.4620	0.1249	2.6300	0.0838
	VG	0.3600	9.97𝐸−05	0.0799	1.0570	0.4665	0.3425	0.1818	1.4560
	LN	0.3653	0.1338	3982.0	4.3040	0.4666	0.3696	13.930	1.3990
	MG	0.3653	0.2126	3.0920	0.4859	0.4687	0.3680	2.9330	1.1190
Sandy clay	BC	0.4074	0.2244	49.820	0.4754	0.4669	0.0547	2.2820	0.0647
	VG	0.4103	0.2647	0.0100	2.4730	0.4718	0.3427	0.2168	1.4010
	LN	0.4106	0.2684	139.50	0.8112	0.4723	0.3734	13.090	1.4870
	MG	0.4116	0.2672	9.9810	2.0240	0.4725	0.3724	2.8360	1.0950
Silty clay	BC	0.3206	9.12𝐸−08	7.5270	0.0628	0.4243	0.0065	13.100	0.1091
	VG	0.3150	9.28𝐸−04	0.0208	1.1060	0.4331	0.1635	0.0442	1.2550
	LN	0.3266	1.27𝐸−05	9142.0	4.2280	0.4350	0.2390	117.50	1.9140
	MG	0.3315	1.24𝐸−05	3.5180	0.3942	0.4382	0.2357	3.9630	0.8314
Clay	BC	0.5513	1.36𝐸−04	43.010	0.0743	0.5437	2.99𝐸−07	11.250	0.1023
	VG	0.5543	3.08𝐸−05	0.0084	1.1130	0.5502	5.73𝐸−04	0.0549	1.1210
	LN	0.5545	0.3147	949.70	2.0800	0.5531	0.2468	251.30	2.5180
	MG	0.5555	0.3466	5.6740	0.8757	0.5559	0.2600	3.6070	0.6748