Wetland invasion by Typhaglauca increases soil methane emissions

• Published in: Aquatic botany Vol. 137; pp. 80 - 87
• Main Authors: Lawrence, Beth A, Lishawa, Shane C, Hurst, Nia, Castillo, Buck T, Tuchman, Nancy C
• Format: Journal Article
• Language: English
• Published: 01.01.2017
• Subjects: Typha; USA
• DOI: 10.1016/j.aquabot.2016.11.012
• ISSN: 0304-3770

Wetland invasion by monotypic dominant plants can alter the physicochemical and biological properties of soils that affect methane emissions, a potent greenhouse gas. We examined the effects of Typhaglauca invasion on soil methane using laboratory incubation and controlled mesocosm experiments. Typha-invaded soils collected from three Midwestern (USA) wetlands had greater methane production potential during laboratory incubation than soils dominated by native wet meadow vegetation. Ten years post-invasion of native plant-dominated mesocosms, Typha increased methane emissions at least three-fold (native: 15.0 plus or minus 10.5mg CH4-Cm-2 h-1, median: 6.1mg CH4-Cm-2h-1; Typha: mean: 45.9 plus or minus 16.7mg CH4-Cm-2h-1, median: 26.8mg CH4-Cm-2h-1) under high (+10cm) water levels, though methane emissions were negligible under low (-10cm) water levels. Methane emissions were positively correlated with soil carbon, nitrogen, and aboveground biomass, all of which were greater in Typha-invaded mesocosms. Together, our data suggest that replacement of large tracts of native wetlands throughout eastern North America with monocultures of invasive Typha could alter regional methane emissions.