Increased methane emissions from an invasive wetland plant under elevated carbon dioxide levels

Wetlands function as important climate regulators by providing conditions for the large-scale production and release of methane from vegetation. Several studies have suggested an apparent link between two global warming gases that result in higher emissions of methane from rice paddies and wetlands subjected to elevated levels of atmospheric CO2. We show that an increase in the relative abundance of methane-producing archaea isolated from the rhizosphere of a highly invasive plant was associated with enhanced plant biomass from CO2-stimulated roots. Methane emissions from a cattail invasive to North America Typha angustifolia (narrow leaf cattail) increased 148% under an enriched atmosphere of CO2 (700 ppm). Root biomass also increased under elevated CO2 for T. angustifolia and was correlated with methane flux, suggesting that future CO2 stimulation may lead to higher methane emissions from Typha-dominated wetlands.

► Methane flux increased 148% from an invasive wetland plant under an enriched atmosphere of CO2. ► Root biomass increased under elevated CO2 for the invasive wetland plant. ► Biomass of the invasive wetland plant was correlated with methane flux.