Cold-Temperate Mountainous Freshwater Produces Methane by Algal Metabolism

作者：Zhongjing Zhao, Tengzhong Zhang, Zhonghua Zhao, Xiaolong Yao, Hui Wang, Lu Zhang · 发表于：Environmental Science & Technology · 年份：2025 · DOI：10.1021/acs.est.4c13468 · 被引用次数：8 · 研究领域：Atmospheric and Environmental Gas Dynamics、Methane Hydrates and Related Phenomena、Microbial Community Ecology and Physiology

We reported important environmental drivers of dissolved CH 4 concentrations (d-CH 4 ) in nutrient-limited mountainous freshwater in a cold-temperate region and explored the potential for multiple known oxic CH 4 production pathways. Field investigation revealed consistent supersaturated d-CH 4 in surface water (relative to the theoretical value of d-CH 4 at atmospheric equilibrium), with significant seasonal variations. Statistical analysis highlighted the direct impact of algal dynamics and the indirect effect of temperature and nutrients on d-CH 4 . Further lab-scale incubation demonstrated that CH 4 production decreased by 55.25 to 93.65% with algae removal, while it increased 4 to 10 times with methylphosphonate (MPn) amendment. These findings argued that CH 4 produced from algal metabolism related to MPn had a high potential for supersaturated d-CH 4 . It also verified the pivotal role of cyanobacteria in this mechanism, with temperature and light acting as regulatory factors. Through highlighting the role of algae for CH 4 characteristics in cold-temperate mountainous freshwater and proposing the potential of oxic CH 4 production through MPn metabolism in nutrient-limited lakes, this study enriches comprehension of aquatic CH 4 cycle and warns about the importance of preserving environmental balance in freshwater with minimal human disturbance.