Yang Wen-Tao, Gu Jiao-Feng, Zou Jia-Ling, Zhou Hang, Zeng Qing-Ru, Liao Bo-Han
College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China.
College of Bioscience and Technology, Hunan Agricultural University, Changsha, 410128, China.
Environ Sci Pollut Res Int. 2016 Oct;23(20):20853-20861. doi: 10.1007/s11356-016-7326-5. Epub 2016 Aug 2.
The objective of the present study was to investigate the effects of rapeseed dregs (RSD, a commonly organic fertilizer in rural China) at application rates of 0, 0.75, 1.5, and 3.0 % on Cd availability in soil and its accumulation in rice plants (Oryza sativa L., Xiangwanxian 12, and Weiyou 46) by means of a pot experiment. The results showed that application of RSD resulted in a sharp decrease in the soil TCLP-extractable Cd content. However, the soil TCLP-extractable Cd content in amended soil gradually increased during the rice growing period. Application of RSD significantly increased Cd transport from root to shoot and the amount of Cd accumulated in the aerial part. RSD was an effective organic additive for increasing rice grain yield, but total Cd content in rice grain was also increased. At an application rate of 1.5-3.0 % RSD, the total Cd content in Weiyou 46 brown rice was 0.27-0.31 mg kg, which exceeded the standard safe limit (0.2 mg kg) and was also higher than that of Xiangwanxian 12 (0.04-0.14 mg kg). Therefore, Weiyou 46 had a higher dietary risk than Xiangwanxian 12 with RSD application. We do not recommend planting Weiyou 46 and applying more than 0.75 % RSD in Cd-contaminated paddy fields.
本研究的目的是通过盆栽试验，研究施用量分别为0%、0.75%、1.5%和3.0%的菜籽粕（RSD，中国农村常用的有机肥料）对土壤中镉有效性及其在水稻植株（Oryza sativa L.，湘晚籼12号和威优46）中积累的影响。结果表明，施用菜籽粕导致土壤TCLP可提取镉含量急剧下降。然而，在水稻生长期间，改良土壤中TCLP可提取镉含量逐渐增加。施用菜籽粕显著增加了镉从根部向地上部的转运以及地上部积累的镉量。菜籽粕是提高水稻产量的有效有机添加剂，但水稻籽粒中的总镉含量也增加了。在1.5%-3.0%的菜籽粕施用量下，威优46糙米中的总镉含量为0.27-0.31 mg/kg，超过了标准安全限值（0.2 mg/kg），也高于湘晚籼12号（0.04-0.14 mg/kg）。因此，施用菜籽粕时，威优46的膳食风险高于湘晚籼12号。我们不建议在镉污染的稻田种植威优46并施用超过0.75%的菜籽粕。
