State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
Sci Total Environ. 2020 Jul 1;724:138294. doi: 10.1016/j.scitotenv.2020.138294. Epub 2020 Mar 28.
The accumulation of heavy metals and the accelerated dissemination of antibiotic-resistance genes (ARGs) in soil receiving long-term manure application are causing worldwide concern. In this study, struvite-supported biochar composite (MAP/BC) obtained by N and P recovery from pig slurry with Mg(OH)-modified biochar (Mg(OH)/BC) was used as a novel amendment for the remediation of Cu- and ARG-contaminated agricultural soil. The effects of MAP/BC on Cu immobilization, ARG distribution, and the bacterial community in the soil were investigated simultaneously. The results showed that the mechanisms involved in the immobilization of Cu by MAP/BC included the formation of copper-phosphate precipitation and a surface complex. With a 10% MAP/BC modification, the acid-soluble Cu content in soil decreased by 0.47-fold at day 56 while the residual Cu content increased 1.41-fold. Meanwhile, the abundances of most of the target ARGs (tetX, tetT, tetW, tetG, ermB, sulI, sulII, and intlI) were reduced by 11.35-99.95%, and the abundance of total ARGs was reduced by 30.69%. The redundancy analysis indicated that the bio-available Cu content played a crucial role in the variations of both ARGs and bacterial communities. The network analysis further suggested that potential hosts of soil ARGs were mainly Firmicutes and Actinobacteria. The above results suggested that the application of MAP/BC can mitigate Cu and ARG pollution in manured soil.
在长期施用粪肥的土壤中，重金属的积累和抗生素抗性基因（ARGs）的加速传播引起了全球关注。在本研究中，采用从猪粪中回收 N 和 P 得到的鸟粪石负载生物炭复合材料（MAP/BC），对 Mg(OH)-改性生物炭（Mg(OH)/BC）进行改性，用作修复 Cu 和 ARG 污染农业土壤的新型改良剂。同时研究了 MAP/BC 对 Cu 固定、ARG 分布和土壤细菌群落的影响。结果表明，MAP/BC 固定 Cu 的机制包括形成铜磷酸盐沉淀和表面络合物。MAP/BC 改性 10%时，土壤中酸溶性 Cu 含量在第 56 天减少了 0.47 倍，而残留 Cu 含量增加了 1.41 倍。同时，大多数目标 ARGs（tetX、tetT、tetW、tetG、ermB、sulI、sulII 和 intlI）的丰度降低了 11.35%-99.95%，总 ARGs 的丰度降低了 30.69%。冗余分析表明，生物可利用 Cu 含量在 ARGs 和细菌群落的变化中起着至关重要的作用。网络分析进一步表明，土壤 ARGs 的潜在宿主主要是厚壁菌门和放线菌门。上述结果表明，MAP/BC 的应用可以减轻粪肥土壤中的 Cu 和 ARG 污染。
