Table 5.

Results of stepwise linear multiple regression analysis.

Plant type	Multiple regression equation*	r2(%)
Corn grain (N=4)	(Zn)s = 47.113 + 0.251 (Zn)s - 7.102 LOI	98.84
Jujube grain (N=8)	(Cu)p = 10.3012 + 0.0068 (Cu)s - 0.3892 pH	83.78
	(Zn)p = 18.12 + 0.05 (Zn)s - 0.78 LOI	90.04
	(Pb)p = 0.0687 + 0.0017 (Pb)s	82.19
Perilla leaves (N=5)	(Cu)p = 20.655 + 0.0253 (Cu)s	93.32
	(Zn)p = 6.6733 + 0.4495 (Zn)s	91.58
Red pepper (N=10)	(Cu)p = 5.0217 + 0.1047 (Cu)s	98.53
	(Zn)p = 21.3541 + 0.0718 (Zn)s	87.84
	(Cd)p = 0.289 + 0.093 (Cd)s - 0.015 pH	87.69
	(Pb)p = 0.1623 + 0.0157 (Pb)s	94.79
Soybean leaves (N=11)	(Cu)p = 81.916 + 0.318 (Cu)s - 4.012 pH - 0.722 sand	96.24
	(Zn)p = -34.261 + 1.369 (Zn)s	70.89
	(Pb)p = 3.614 + 0.006 (Pb)s - 0.341 pH	86.94
Spring onions (N=8)	(Cu)p = 17.916 + 0.067 (Cu)s - 3.601 pH - 0.853 silt	94.35
	(Zn)p = 516 + 2.28 (Zn)s - 124 pH	94.17
	(Cd)p = -0.291 + 0.347 (Cd)s - 0.477 pH + 0.532 LOI	96.31
	(Pb)p = 14.143 + 0.051 (Pb)s - 0.186 sand	90.18

Note : (Cu)p = Cu in plant (μg g⁻¹, dry weight); (Cu)s = Cu in surface soil (μg g⁻¹);

^*P < 0.01