Rewetting peatlands and methane emissions

Nº 43

Sacramento-San Joaquin Delta, North California

some attempts made
past case
ongoing case
no attempts made


Rewetting peatlands and methane emissions

Wetlands in the Sacramento-San Joaquin Delta in northern California have been restored with the aim of removing carbon dioxide from the atmosphere and increasing carbon storage in the soil. It has been found that the newly flooded conditions of the wetlands lead to reduced carbon dioxide emissions from decomposition, and that the intervention helps to sequester carbon, but also leads to the production and increased emission of methane under anaerobic conditions – a biogeochemical trade-off. Delta wetlands are often net sources of greenhouse gases on an annual basis throughout the study period, although they tend to act as sinks during summer periods due to high carbon uptake.

The oxidation of the rhizosphere through vascular plants can reduce methane production and emission in rewetted peatlands.

Agethen, S., Sander, M., Waldemer, C., & Knorr, K. H. (2018). Plant rhizosphere oxidation reduces methane production and emission in rewetted peatlands. Soil Biology and Biochemistry, 125, 125-135.

Hemes, K. S., Chamberlain, S. D., Eichelmann, E., Knox, S. H., & Baldocchi, D. D. (2018). A biogeochemical compromise: The high methane cost of sequestering carbon in restored wetlands. Geophysical Research Letters, 45, 6081– 6091.