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Abstract: Weekly profiles of dissolved methane concentrations, dissolved oxygen, temperature, and light were measured during three summers (2018, 2019, and 2024) in two north temperate lakes. One of the lakes was experimentally enriched with nitrogen and phosphorus during two summers (2019 and 2024), and darkened using a blue dye in one summer (2024). The other lake was an unmanipulated reference. Using this series of whole-lake enrichment and shading experiments across three years with varying ice phenology, we assessed how eutrophication and ice cover affect within-year methane storage.
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This content will become publicly available on May 1, 2027
Eutrophication and ice phenology influence methane storage in north temperate lakes
Abstract Among lakes, eutrophication is positively related to methane emissions, but various processes can alter the seasonal conversion of primary production into stored methane. We used a series of whole‐lake enrichment and shading experiments across three years with varying ice phenology to assess how eutrophication and ice cover affect within‐year methane storage. The seasonal pattern of methane storage was driven in part by cyanobacteria blooms and their influence on light and oxygen availability. Early ice‐off reduced anoxic volume and methane storage in both the manipulated and reference lake, but a subsequent bloom and shading in the manipulated lake drove a rapid increase in methane, with storage reaching similar levels to those of other years. These experiments revealed that interactions between ice phenology and eutrophication can drive shifts in seasonal methane storage trajectories in north temperate lakes. Improved understanding of variability in these drivers could substantially reduce uncertainty in lake methane emissions.
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- PAR ID:
- 10704685
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Limnology and Oceanography Letters
- Volume:
- 11
- Issue:
- 3
- ISSN:
- 2378-2242
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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