Factors affecting the availability to radishes of cadmium added to soil

Abstract

In a five week period, the cadmium uptake of radishes in pot experiments made in the greenhouse was on average 7.8 % of the cadmium mixed with the soil (0.4 mg Cd per 400 ml of soil). In a material consisting of samples from 25 plough layers the uptake varied from 1.4 to 11 % and in a material of samples from the corresponding subsoils from 14 to 22.6 %. The increase in cadmium content (∆ c) of the radish tops, which increase was regarded here as describing best the availability of added cadmium, varied in the plough layer material from 2.2 to 27.1 mg/kg and in the subsoil material from 4.3 to 94.9 mg/kg Cd on a dry matter basis. The increment ∆ c was related to the amount of organic carbon (x1) and to proportion of hydrogen (x2)) of total exchangeable cations according to the equation ∆ c = k * x2 *b2 /x1*b1. In this equation 0