Occurrence of Vanadium in Belgian and European Alluvial Soils

Table 6

Regression equations for the different areas with V (logtransformed) as dependent variable.

Area	Regression equation	R²
3 Belgian floodplains	^alog V = −3.172 + 0.433 log Al + 0.367 log Mg + 0.399 log Fe + 0.058 log P**	0.831
	^blog V = −2.956 + 0.424 log Al + 0.341 log Mg + 0.312 log Fe + 0.068 log P**	0.920
floodplain of the Geul	^alog V = −1.424 + 0.507 log Al + 0.174 log Fe**	0.606
	^blog V = −1.342 + 0.503 log Al + 0.160 log Fe**	0.634
floodplain of the Grote Beek	^alog V = −2.820 + 0.761 log Al + 0.196 log Mg +0.207 log P **	0.809
floodplain of the Leie	^alog V = −4.244 + 0.945 log Al + 0.368 log Mg + 0.315 log clay**	0.824
	^blog V = −3.870 + 0.775 log Al + 0.472 log Mg + 0.330 log clay**	0.900
Europe	^alog V = 1.041 + 1.32 log Fe + 0.413 log Al + 0.102 log Mg**	0.836
	^blog V = 1.108 + 1.33 log Fe + 0.279 log Al + 0.086 log Mg**	0.880

^a In the first regression equation, outliers are included.^b The second regression equation is without outliers. **Significant at 0.01 level.