The effect of algal bloom on the emission flux of nitrous oxide from <i>Chironomus plumosus</i> larvae

作者：S.L. Xu, He XiaoYun, Yang Liuyan · 发表于：Journal of Lake Sciences · 年份：2018 · DOI：10.18307/2018.0415 · 研究领域：Aquatic Ecosystems and Phytoplankton Dynamics

底栖动物是湖泊生态环境的重要组成部分，在泥水界面氮循环中扮演着重要的作用，是一个潜在的N 2 O排放源，但其在富营养化湖泊中N 2 O排放机制还不清楚.通过室内微宇宙实验，采用气相色谱和现代分子生物学相结合的技术，研究蓝藻存在时底栖动物摇蚊幼虫排放N 2 O特征及其内在生物学机制.结果显示底栖动物羽摇蚊幼虫（Chironomus plumosus）肠道是N 2 O排放的主要场所，约占活体释放通量的77%.蓝藻存在时羽摇蚊幼虫的N 2 O排放通量减少60%左右，肠道内细菌多样性明显下降，肠道中β-变形菌相对丰度增加21%，δ-变形菌相对丰度减少62%，从而改变肠道内细菌群落结构；同时肠道内nirS基因多样性显著增加，出现较多的nirS型反硝化菌的表型，硝酸盐的还原作用得到增强.研究结果有助于揭示富营养化湖泊底栖动物摇蚊幼虫的环境效应，丰富湖泊氮素生物地球化学循环的新过程.;Zoobenthos is an indispensable constituent of lake eco-environment and plays an important role in nitrogen cycle between sediment and water. Zoobenthos is the potential source of N 2 O emission. However, it is still need to further study on the N 2 O emission mechanism of zoobenthos in the region of algal accumulation. Thus, the combining gas chromatography with modern molecular biological techniques was used to analyze the N 2 O emission flux and intestinal microorganism to extend our knowledge about the microbiological mechanism of N 2 O emission in eutrophic lake. The results showed that the N 2 O emission flux of the gut of Chironomus plumosus larvae decreased about 60%, which accounted for 77% of the total emission flux form C. plumosus, indicating that the gut was the major N 2 O emission site of C. plumosus larvae. The intestinal bacterial diversity of C. plumosus larvae would decrease with the presence of algal bloom, while the bacterial community structure also changed, the relative abundance of β-proteobacteria increased 21%, whereas δ-proteobacteria decreased 62%. The diversity of ...