Estimating Salt Concentrations Based on Optimized Spectral Indices in Soils with Regional Heterogeneity

Table 2

Statistical characteristics of SSC in sampling area soil (g·kg⁻¹).

Field sites	Modeling set	Sample sites	Max value	Min value	Mean value	SD	CV (%)
Ebinur Lake Basin	Whole set	57	56.4	0	8.29	11.80	142
	Calibration set	38	56.4	0	8.33	13.08	157
	Validation set	19	27.7	1.1	8.21	9.04	110
Ugan-Kuqa Oasis	Whole set	49	69.8	0	19.30	19.99	104
	Calibration set	33	69.8	0	16.78	18.65	111
	Validation set	16	65.1	3.9	24.06	22.09	92
Keriya Oasis	Whole set	98	17.8	0	4.99	4.33	87
	Calibration set	65	17.8	0	5.36	4.32	81
	Validation set	33	12.9	0.5	4.225	4.39	104