Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China.
Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China.
Ecotoxicol Environ Saf. 2019 Apr 30;171:425-434. doi: 10.1016/j.ecoenv.2019.01.006. Epub 2019 Jan 9.
The effects of the continuous amendments with lime (L), lime mixed with organic manure (LO), or phosphate fertilizer (LP) on the soil bacterial community, soil available cadmium (Cd) content, and Cd accumulation in rice planted in a Cd contaminated paddy soil were determined through a four-season field experiment. The results showed that with continuous application of amendments during the four seasons, the soil pH increased significantly compared with the control, while the soil available Cd content significantly decreased by 12.9-18.2%, 13.1-17.3% and 0.09-23.2% under the L, LO, or LP treatments, and the Cd content of rice was significantly reduced by 28.5-56.2%, 37.6-53.4%, and 31.2-44.6%, respectively. The rice Cd content in each season at amendment treatments was lower than the National Food Safety Standard of China (maximum level of Cd in grains is 0.2 mg/kg). The diversity and richness of soil bacteria significantly increased after the continuous amendments in soil for four-season cropping. Soil pH and available Cd content were important factors for soil bacterial community. Lime mixed with phosphate fertilizer or organic manure had been characterized by a significant increase of Proteobacteria, Nitrospirae, and Chloroflexi and a decrease of Acidobacteria based on an Illumina Miseq sequencing analysis. The results indicate that the continuous application of lime mixed with organic manure or phosphate fertilizer is a very important measure to ensure the quality safety of rice and improve soil quality in a Cd-contaminated paddy.
通过一个四季田间试验，研究了石灰（L）、石灰与有机肥（LO）或磷肥（LP）连续配施对污染土壤中细菌群落、土壤有效态镉（Cd）含量和水稻 Cd 积累的影响。结果表明，与对照相比，四个季节连续施用改良剂后，土壤 pH 值显著升高，而 L、LO 或 LP 处理下土壤有效态 Cd 含量分别显著降低了 12.9-18.2%、13.1-17.3%和 0.09-23.2%，水稻 Cd 含量分别显著降低了 28.5-56.2%、37.6-53.4%和 31.2-44.6%。各季节改良处理的水稻 Cd 含量均低于中国食品安全国家标准（谷物中 Cd 的最大限量为 0.2mg/kg）。土壤连续四季种植后，土壤细菌多样性和丰富度显著增加。土壤 pH 值和有效态 Cd 含量是土壤细菌群落的重要因素。石灰与磷肥或有机肥混合具有增加变形菌门、硝化螺旋菌门和绿弯菌门，减少酸杆菌门的特点，基于 Illumina Miseq 测序分析。结果表明，连续施用石灰与有机肥或磷肥是确保水稻质量安全和改善污染稻田土壤质量的重要措施。
