Effect of Freeze-thawing Cycles on the Form Transformation of Cadmium in Soil
Yulong Zhang · T'u Jang T'ung Pao · 2008
Brown earth as experimental soil, the effect of freeze-thawing cycles on the forms fractionation of cadmium adding into the soil was studied by the method of chemical sequential extraction in indoor incubation experiment. It adopted stepwise regression analysis to process the data. The results showed that form transformation of cadmium occurred after adding cadmium into soil. Exchangeable cadmium was the main form, secondly was residual form, the content of organic-binding cadmium and Fe-Mn oxide-binding forms were relatively low. The effect of water and frequency on the contents of different forms reached a very significant level under freeze-thawing cycles(p0.01). Optimal regression equations about the effect of water and frequency on different forms contents of cadmium were obtained by stepwise regression analysis.