Lee Eun-Hee, Moon Kyung-Eun, Kim Tae Gwan, Cho Kyung-Suk
Global Top5 Research Program, Department of Environmental Science and Engineering, Ewha Womans University, 52, Ewhayeodae-gil, Seodaemun-gu, Seoul, 120-750, Republic of Korea.
Global Top5 Research Program, Department of Environmental Science and Engineering, Ewha Womans University, 52, Ewhayeodae-gil, Seodaemun-gu, Seoul, 120-750, Republic of Korea.
J Biotechnol. 2014 Aug 20;184:56-62. doi: 10.1016/j.jbiotec.2014.05.006. Epub 2014 May 23.
The depth profiles of the CH4 oxidation potentials and the methanotrophic community were characterized in a lab-scale soil mixture biocover. The soil mixture samples were collected from the top (0-10cm), middle (10-40cm), and bottom (40-50cm) layers of the biocover where most of methane was oxidized at the top layer due to consumption of O2. Batch tests using serum bottles showed that the middle and bottom samples displayed CH4 oxidation activity under aerobic conditions, and their CH4 oxidation rates were 85 and 71% of the rate of top sample (8.40μmolgdry sample(-1)h(-1)), respectively. The numbers of methanotrophs in the middle and bottom were not significantly different from those in the top sample. There was no statistical difference in the community stability indices (diversity and evenness) among the methanotrophic communities of the three layer samples, even though the community structures were distinguished from each other. Based on microarray analysis, type I and type II methanotrophs were equally present in the top sample, while type I was more dominant than type II in the middle and bottom samples. We suggested that the qualitative difference in the community structures was probably caused by the difference in the depth profiles of the CH4 and O2 concentrations. The results for the CH4 oxidation potential, methanotrophic biomass, and community stability indices in the middle and bottom layer samples indicated that the deeper layer in the methanotrophic biocover serves as a bioresource reservoir for sustainable CH4 mitigation.
在实验室规模的土壤混合物生物覆盖层中，对甲烷氧化电位和甲烷营养群落的深度分布特征进行了研究。土壤混合物样本取自生物覆盖层的顶层（0 - 10厘米）、中层（10 - 40厘米）和底层（40 - 50厘米），由于氧气消耗，大部分甲烷在顶层被氧化。使用血清瓶进行的批次试验表明，中层和底层样本在有氧条件下表现出甲烷氧化活性，其甲烷氧化速率分别为顶层样本（8.40μmol g干样本(-1) h(-1)）速率的85%和71%。中层和底层的甲烷营养菌数量与顶层样本无显著差异。三层样本的甲烷营养群落的群落稳定性指数（多样性和均匀度）没有统计学差异，尽管群落结构彼此不同。基于微阵列分析，I型和II型甲烷营养菌在顶层样本中均有等量存在，而在中层和底层样本中I型比II型更占优势。我们认为群落结构的质性差异可能是由甲烷和氧气浓度的深度分布差异造成的。中层和底层样本的甲烷氧化电位、甲烷营养生物量和群落稳定性指数结果表明，甲烷营养生物覆盖层的较深层作为可持续甲烷减排的生物资源库。
