Productive African lakes may oxidize more methane than a simple ‘more algae, more methane’ story predicts
WHAT THE EVIDENCE SAYS
Across 79 African lakes, methane oxidation was strongest in productive waters and in lakes draining Congo Basin wetlands. The authors estimate oxidation removed more than 70% of dissolved methane in the mixed layer. Photosynthesis-driven oxic methane production contributed much less than oxidation and diffusion, and its relative contribution declined as lake productivity increased.
WHY IT MATTERS / OUR READ
Lake methane budgets cannot be inferred from productivity or surface methane concentration alone. The balance between production, oxidation, inflow and evasion determines atmospheric exposure, so monitoring that omits the microbial sink can misread how lake condition translates into climate forcing.
CAVEATS / UNCERTAINTY
This is a comparative observational study across diverse lakes. Some process explanations, including the role of methanotroph attachment and wetland inputs, are inferred from patterns rather than directly manipulated, and the sampled lakes do not represent every African lake type.
SOURCE
Nature Communications — primary study
View original evidence ↗
Across 79 lakes, methane oxidation strengthened with productivity and accounted for more than 70% of dissolved methane removal in the mixed layer, while photosynthesis-driven oxic methane production was comparatively small.
Read the Wild Lands assessment →