ABSTRACT
Most carbon (C) stored in coastal wetlands lies belowground, yet the critical belowground responses of roots and microbial respiration to warming are far more difficult to assess than the aboveground responses. Coastal wetlands have been recognized as important C sinks, and therefore the response of C cycling to climate change in tidal wetlands is largely unexplored. Warming is expected to influence the aboveground and belowground feedback loops that regulate soil C sequestration, elevation gain, methane emissions, and hydrologic export of C and nitrogen. Few experimental manipulations in wetlands have tested hypotheses about the effects of warming on ecological interactions. Numerical models are one approach to forecasting temperature effects on tidal marsh elevation and C sequestration. The potential of warming and ensuing sea level rise to alter plant community composition represents a large uncertainty for predicting future ecosystem C dynamics in tidal marshes and tidal forests.
