Effects of mixed amendments on the phytoavailability of Cd in contaminated paddy soil under a rice-rape rotation system.
A field experiment was performed to study the effects of mixed amendments, namely lime + organic fertilizer (LO), lime + organic fertilizer + calcium-magnesium phosphate fertilizer (LOC), lime + organic fertilizer + sepiolite (LOS), and lime + organic fertilizer + calcium-magnesium phosphate fertilizer + sepiolite (LOCS), on the availability and uptake of Cd from contaminated paddy soil under a rice-rape (Oryza sativa L. and Brassica napus L.) rotation system. The results showed that the grain yields of rice and rape with mixed amendment-treated were slightly influenced, in that the soil pH significantly increased while the DTPA-extractable Cd content of the soil and Cd uptake by the rice and rape were significantly reduced. The uptake of Cd by brown rice decreased significantly (p < 0.05), by 55.9-59.3% and 69.6-75.5% in the 2016 and 2017 crops, respectively, compared with that of the control (CK). The Cd uptake by rapeseeds during the 2017 season observably (p < 0.05) decreased by 38.2 and 29.6% under LO and LOC treatments, respectively. The Cd concentrations in rapeseeds were 0.11-0.18 mg kg-1 under all the treatments except LOCS treatment, which is lower than the National Standard of Pollutants in Food of China (GB 2762-2017, 0.2 mg kg-1). From both economic and food safety standpoints, rape is recommended for Cd-contaminated soil because it has a low Cd accumulation ability. The results showed that the rice-rape rotation combined with LO or LOC application was useful for reducing the Cd content in both rice and rape in Cd-contaminated soil and the effects could be sustained at least for three crop seasons.
['Ran|Hongzhen|H|', 'Guo|Zhaohui|Z|http://orcid.org/0000-0002-0916-455X', 'Shi|Lei|L|', 'Feng|Wenli|W|', 'Xiao|Xiyuan|X|', 'Peng|Chi|C|', 'Xue|Qinghua|Q|']
D000383:Agriculture D001682:Biological Availability D029688:Brassica napus D002104:Cadmium D002118:Calcium D017610:Calcium Compounds D002681:China D018556:Crops, Agricultural D005308:Fertilizers D017616:Magnesium Compounds D017633:Magnesium Silicates D012275:Oryza D010087:Oxides D010710:Phosphates D012987:Soil D012989:Soil Pollutants
Mixed amendments Cd Paddy soil Rice-rape rotation Immobilize