Correlation between Cadmium Content in Paddy Soil and in Rice
In 2012,the rice planting area irrigated by river was chosen to investigate the correlation between cadmium (Cd) pollution in paddy soil and in rice.The results showed that the content of Cd in paddy soil ranged from 0.02 mg/kg to 2.45 mg/kg,so there was light Cd pollution in this area.There was a significant positive correlation between Cd content in paddy soil and in rice (P<0.05),rice from non-polluted paddy soil may have excessive Cd contamination risk.According to correlative equation of Cd in rice and in soil,the threshold value for Cd content in paddy soil was calculated as 0.27 mg/kg,which was close to secondary performing standards of Ⅱ class soil environmental quality in the Soil Environment Quality Standard (GB15618-1995).The threshold value could provide scientific references for rice production safety in the area.