氧改性斜发沸石缓解缺氧沉积物甲烷释放的模拟研究  

Effects of oxygen-modified clinoptilolite on methane emission in sediment-water interface:A laboratory simulated study

作　　者：武华杰 李诗月 冯丽娟[1] 张大海[1] 李先国[1] WU Huajie;LI Shiyue;FENG Lijuan;ZHANG Dahai;LI Xianguo(College of Chemistry and Chemical Engineering,and Key Laboratory of Marine Chemistry Theory and Technology Ocean University of China,Ministry of Education,Qingdao,266000,China)

机构地区：[1]中国海洋大学化学化工学院,海洋化学理论与工程技术教育部重点实验室,青岛266000

出　　处：《环境化学》2022年第6期2087-2093,共7页Environmental Chemistry

摘　　要：富营养化导致藻类过度繁殖和缺氧频发,易引发甲烷大量释放,已经成为河口和近岸海域严重的环境问题.本研究通过氧改性斜发沸石制备氧纳米气泡,用于模拟研究原位修复缺氧沉积环境和缓解沉积物甲烷释放.氧改性斜发沸石覆盖缺氧沉积物12 h后,上覆水中溶解氧含量从0.22 mg·L^(−1)上升至4.28 mg·L^(−1),氧化还原电位由−59 mV上升至2 mV;沉积物向上覆水释放的20 d累积甲烷通量比未覆盖组下降了99.0%;荧光定量PCR对产甲烷古菌丰度进行绝对定量的结果表明,上层沉积物中产甲烷古菌丰度从8.90×10^(7)拷贝数·g^(−1)下降至1.65×10^(7)拷贝数·g^(−1).氧改性斜发沸石形成的有氧覆盖层能够显著抑制产甲烷古菌的活性,有效缓解沉积物甲烷释放,是可行的原位修复缺氧沉积环境的手段.Methane emission in sediment-water interface has been a serious environmental problem in hypoxic estuaries and coastal waters.In this study,oxygen nanobubbles were prepared by oxygenmodified clinoptilolite to perform a simulation experiment of remediating anoxic sedimentary environment and mitigating methane emission.After oxygen-modified clinoptilolite were delivered to anoxic sediment,the concentration of dissolved oxygen improved from 0.22 mg·L^(−1) to 4.28 mg·L^(−1) and the redox potential increased from−59 mV to 2 mV in 12 hours.The 20-day cumulative methane emission decreased by 99.0%compared with the control group,demonstrating that oxygen-modified clinoptilolite significantly mitigated the release of methane caused by the deposition and remineralization of algae.In addition,methanogens were quantified based on mcrA gene by using qPCR method.Abundances of mcrA gene decreased from 8.90×107 copies·g^(−1) to 1.65×107 copies·g^(−1) in surface sediment after the application of oxygen nanobubbles,accompanied by methanogenesis suppression.Hence this could propose a promising strategy for sustainable remediation of anoxia and mitigation of methane emission.

关 键 词：天然沸石 缺氧沉积物 氧纳米气泡 原位修复 甲烷通量 产甲烷古菌 

分 类 号：X52[环境科学与工程—环境工程] X55