Effects of triclosan and triclocarban on denitrification and N2O emissions in paddy soil
Effects of triclosan and triclocarban on denitrification and N2O emissions in paddy soil
复制标题
三氯生和三氯卡班对水稻土反硝化和N2O排放的影响
DOI：
10.1016/j.scitotenv.2019.133782
复制
发表时间：
2019
影响因子：
9.8
通讯作者：
Shan Jun
中科院分区：
文献类型：
--
作者：
Chen Shuntao;Chee-Sanford Joanne C.;Yang Wendy H.;Sanford Robert A.;Chen Jianqiu;Yan Xiaoyuan;Shan Jun
三氯生（TCS）和三氯卡班（TCC）是两种常见的抗菌化合物，广泛用作药物和个人护理产品的成分。它们普遍存在于土壤中，由于生物固体作为农业肥料的应用，但它们对微生物介导的土壤生物地球化学过程的影响知之甚少。研究了不同浓度的TCS和TCC单独和联合施用对水稻土反硝化作用和N2 O排放的影响。我们还定量反硝化功能基因丰度通过q-PCR来阐明TCS和TCC的效果的微生物机制。我们的研究结果表明，TCS和TCC暴露单独和共同显著（p< 0.05）抑制反硝化（7.0-36.7%）和N2 O排放（15.4-86.4%），除了0.01 mg kg− 1 TCC处理，其中反硝化轻微但显著（p< 0.05）刺激。TCS和TCC暴露的抑制作用主要归因于其对细菌的负净效应，如TCS和TCC处理中16 S rRNA、narG、nirK和分支InosZ基因丰度的降低所示。总之，我们发现，TCS和TCC暴露在稻田土壤中可以显着改变稻田生态系统中的氮循环，通过抑制反硝化和N2 O排放。在评价TCS和TCC的环境影响时，应考虑这些影响。
Triclosan (TCS) and triclocarban (TCC) are two common antimicrobial compounds, which are widely used as ingredients in pharmaceuticals and personal care products. They occur ubiquitously in soil due to biosolid application as agricultural fertilizers, but their influence on microbially mediated soil biogeochemical processes is poorly understood. We tested the effects of varying concentrations of TCS and TCC applied both individually and together on denitrification and N2O emissions in paddy soil. We also quantified denitrification functional gene abundances byq-PCR to elucidate the microbial mechanisms of TCS and TCC's effects. Our results showed that TCS and TCC exposure both individually and together significantly (p< 0.05) inhibited denitrification (7.0–36.7%) and N2O emissions (15.4–86.4%) except for the 0.01 mg kg−1TCC treatment in which denitrification was slightly but significantly (p< 0.05) stimulated. The inhibitory effects of TCS and TCC exposure were mainly attributed to their negative net effects on denitrifying bacteria as suggested by the decrease in abundances of 16S rRNA,narG,nirKand clade InosZgenes in the TCS and TCC treatments. Overall, we found that TCS and TCC exposure in paddy soil could substantially alter nitrogen cycling in rice paddy ecosystems by inhibiting denitrification and N2O emissions. These effects should be taken into consideration when evaluating the environmental impacts of TCS and TCC.