Table 5.

The modeling results of different soils and temperatures by CARS.

Group	Soil Type		Calibration Set			Prediction Set
		N1	Rc	RMSEC (g/kg)	N2	Rp	RMSEP (g/kg)	RPD
1 (50 °C)	Black soil	118	0.9625	0.163	58	0.9416	0.185	2.95
	Loess	118	0.9009	0.1875	58	0.8966	0.1885	1.61
	Calcium soil	118	0.9281	0.1549	58	0.8977	0.1414	2.43
2 (80 °C)	Black soil	118	0.9205	0.25	58	0.9288	0.237	2.68
	Loess	118	0.93	0.106	58	0.9412	0.105	2.90
	Calcium soil	118	0.9117	0.136	58	0.9258	0.119	2.79
3 (95 °C)	Black soil	118	0.9731	0.146	58	0.9021	0.277	2.24
	Loess	118	0.9609	0.077	58	0.9612	0.079	3.92
	Calcium soil	118	0.9381	0.118	58	0.9472	0.112	3.07
4 (25 °C)	Black soil	118	0.5458	0.551	58	0.5763	0.476	1.31
	Loess	118	0.5615	0.247	58	0.3862	0.265	1.15
	Calcium soil	118	0.3698	0.322	58	0.4241	0.304	1.13