Environmental Futures Research Institute, School of Natural Sciences, Griffith University, Brisbane, Queensland 4111, Australia; Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
Environmental Futures Research Institute, School of Natural Sciences, Griffith University, Brisbane, Queensland 4111, Australia; Department of Science, Information Technology and Innovation, Dutton Park, Queensland 4102, Australia.
Sci Total Environ. 2017 Dec 1;599-600:254-263. doi: 10.1016/j.scitotenv.2017.05.011. Epub 2017 May 4.
Agrochemical applications may have unintended detrimental effects on soil microorganisms and soil health. However, limited studies have been conducted to evaluate the effects of repeated fungicide applications and interactive effects of different agrochemical applications on soil microorganisms. In this study, an incubation experiment was established to evaluate the potential influences of the fungicide iprodione and the nitrification inhibitor 3, 4-dimethylpyrazole phosphate (DMPP) on soil enzyme activities and bacterial properties. Weekly iprodione applications decreased the activities of all enzymes tested, and DMPP application inhibited soil urease activity. Compared with the blank control, bacterial 16S rRNA gene abundance decreased following repeated iprodione applications, but increased after DMPP application. After 28days of incubation, the treatment receiving both iprodione and DMPP application had higher bacterial 16S rRNA gene abundance and Shannon diversity index than the treatment with iprodione applications alone. Repeated iprodione applications significantly increased the relative abundance of Proteobacteria, but decreased the relative abundances of Chloroflexi and Acidobacteria. Simultaneously, bacterial community structure was changed by repeated iprodione applications, alone or together with DMPP. These results showed that repeated iprodione applications exerted negative effects on soil enzyme activities, bacterial biomass and community diversity. Moreover, relative to iprodione applications alone, additional DMPP application could alleviate the toxic effects of iprodione applications on bacterial biomass and community diversity.
农用化学品的应用可能会对土壤微生物和土壤健康产生意想不到的有害影响。然而，目前关于重复使用杀菌剂以及不同农用化学品应用的交互作用对土壤微生物的影响的研究还很有限。本研究通过培养实验，评估了杀菌剂异菌脲和硝化抑制剂 3,4-二甲基吡唑磷酸盐（DMPP）对土壤酶活性和细菌特性的潜在影响。每周使用异菌脲处理会降低所有测试酶的活性，而 DMPP 的应用则抑制了土壤脲酶的活性。与空白对照相比，重复使用异菌脲处理后细菌 16S rRNA 基因丰度降低，但 DMPP 处理后增加。经过 28 天的培养，同时施用异菌脲和 DMPP 的处理的细菌 16S rRNA 基因丰度和 Shannon 多样性指数均高于单独使用异菌脲的处理。重复使用异菌脲显著增加了变形菌门的相对丰度，但降低了 Chloroflexi 和 Acidobacteria 的相对丰度。同时，单独或与 DMPP 一起重复使用异菌脲会改变细菌群落结构。这些结果表明，重复使用异菌脲对土壤酶活性、细菌生物量和群落多样性产生了负面影响。此外，与单独使用异菌脲相比，额外添加 DMPP 可以减轻异菌脲对细菌生物量和群落多样性的毒性作用。
