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

Table 4

Statistical characteristics of the eight major ions in sampling area soil (g·kg⁻¹).

Field sites	Statistics	K^+	Na^+	Ca^2+	Mg^2+	Cl^−	SO4^2−	HCO3^−	CO3^2−
Ebinur Lake Basin	Max	0.852	158.661	16.248	1.236	182.232	60.519	2.814	0.723
	Min	0.005	0.678	0.048	0.010	0.496	0.284	0.281	0.000
	Mean	0.230	10.089	3.124	0.276	8.303	12.841	1.699	0.014
	SD	0.170	21.328	3.629	0.252	24.768	12.957	0.661	0.100
Ugan-Kuqa Oasis	Max	3.776	161.776	16.012	16.566	205.900	127.770	4.784	1.000
	Min	0.002	0.040	0.028	0.023	0.000	0.182	0.844	0.000
	Mean	0.563	48.294	4.948	1.803	46.365	23.043	2.357	0.018
	SD	0.684	55.599	4.133	3.619	57.746	24.353	0.880	0.134
Keriya Oasis	Max	1.390	72.581	11.124	2.152	82.833	36.429	4.784	0.000
	Min	0.002	0.004	0.040	2.152	0.000	0.072	0.281	0.000
	Mean	0.284	6.341	3.366	0.385	6.916	12.505	2.039	0.000
	SD	0.260	11.114	2.936	0.462	11.971	10.209	0.862	0.000