Plants as conduit for methane in wetlands

Abstract

Next to CO₂, methane is the most important greenhouse gas. Methane is produced by methanogenic bacteria under anoxic conditions, and tropical wetlands are among the most important sources of methane for the atmosphere. In order to cope up with the anoxic conditions the wetland plants have developed morphological features to facilitate oxygen transport to the rhizosphere. This same transport pathway is also utilized for emission of methane produced in the anoxic layers of the habitat to the atmosphere. The methane transport efficiency, however, differs from species to species and depends upon the magnitude of aerenchyma development and root porosity. Methane release site in plants may or may not be stomata.