College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
Environ Sci Pollut Res Int. 2019 Dec;26(36):37082-37091. doi: 10.1007/s11356-019-06545-5. Epub 2019 Nov 19.
Municipal solid waste landfills are not only a crucial source of global greenhouse gas emissions; they also produce large amounts of ammonia (NH), hydrogen sulfide, and other odorous gases that negatively affect the regional environment. Several types of methane-oxidizing bacteria (MOB) were proved to be effective in mitigating methane emission from landfills. Nevertheless, more MOB species and their technical parameters for best mitigating methane still need to be explored. In landfills, methane is simultaneously generated with ammonia, which may impede the CH bio-oxidizing process of MOB. However, very limited studies examined the enhancement of methane reduction by introducing ammonia-oxidizing bacteria (AOB) in landfills. In this study, two enriched MOB cultures were gained from a typical municipal solid waste landfill, and then were cultured with three strains of ammonia-oxidizing bacteria (AOB). The MOB enrichment culture used in this work includes Methylocaldum, Methylocystaceae, and Methyloversatilis, with a methane oxidation capacity of 43.6-65.0%, and the AOB includes Candida ethanolica, Bacillus cereus, and Alcaligenes faecalis. The effects on the emission reduction of both NH and CH were measured using self-made landfill-simulating equipment, as MOB, AOB, and a MOB-AOB mixture were added to the soil cover of the simulation equipment. The concentrations of CH and NH in the MOB-AOB mixture group decreased sharply, and the CH and NH concentration was 76.4% and 83.7% of the control group level. We also found that addition of AOB can help MOB oxidize CH and improve the emission reduction effect.
城市固体废物填埋场不仅是全球温室气体排放的重要来源，还会产生大量的氨（NH）、硫化氢和其他恶臭气体，对区域环境产生负面影响。几种类型的甲烷氧化菌（MOB）已被证明可有效减少垃圾填埋场的甲烷排放。然而，仍需要探索更多的 MOB 物种及其最佳缓解甲烷的技术参数。在垃圾填埋场中，甲烷与氨同时产生，这可能会阻碍 MOB 的 CH 生物氧化过程。然而，很少有研究探讨在垃圾填埋场中引入氨氧化菌（AOB）来增强甲烷减排。在这项研究中，从一个典型的城市固体废物填埋场中获得了两种富集的 MOB 培养物，然后用三种氨氧化菌（AOB）对其进行培养。本工作中使用的 MOB 富集培养物包括 Methylocaldum、Methylocystaceae 和 Methyloversatilis，甲烷氧化能力为 43.6-65.0%，AOB 包括 Candida ethanolica、Bacillus cereus 和 Alcaligenes faecalis。使用自制的垃圾填埋模拟设备测量了 NH 和 CH 的减排效果，向模拟设备的土壤覆盖层中添加了 MOB、AOB 和 MOB-AOB 混合物。MOB-AOB 混合物组中 CH 和 NH 的浓度急剧下降，CH 和 NH 的浓度分别为对照组水平的 76.4%和 83.7%。我们还发现，添加 AOB 可以帮助 MOB 氧化 CH 并提高减排效果。
