Submergence inhibits photosynthesis by terrestrial wetland plants, but less so in species that possess leaf gas films when submerged. Floodwaters are often supersaturated with dissolved CO2enabling photosynthesis by submerged terrestrial plants, although rates remain well-below those in air. This newly published paper byΒ Timothy D. Colmer, Anders Winkel, and Ole Pedersen reviews this important adaptation that enhances survival in submerged conditions.