Table 2.

Statistical results of heavy metal elements, SOM, and water content for soil samples.

Elements	Calibration/Validation Set		Validation Statistics		Soil Organic Matter (%)	Water Content (g)
	Cr (mg/kg)	Ni (mg/kg)	Cr (mg/kg)	Ni (mg/kg)
Mean	16.59	5.78	22.02	7.49	2.93	5.06
Std.	3.73	2.28	4.70	2.07	1.52	3.8
Kurtosis	0.11	0.7	−0.58	−0.09	−0.18	−0.01
Skewness	−0.24	−0.56	−0.54	−0.37	0.2	0.52
Min.	8.02	0.01	13.52	3.88	0.04	0
Max.	24.12	10.22	27.25	10.69	6.82	15.5
n	37	37	9	9	37	37
CV	0.22	0.39	0.21	0.28	0.52	0.75
K-S test Asymp.Sig.	0.2	0.2	0.2	0.2	0.2	0.2
Background value	21.15	10.07	21.15	10.07
Secondary standard (pH > 7.5)	250	60	250	60

n: number, CV: coefficient of variation.