RE: Chemistry of Waterlogged Soils
One text I've seen that addresses this subject to at least some degree is 'The Biology of Aquatic Vascular Plants' by C.D. Sculthorpe reprinted in 1985 by Koeltz Scientific Books.
One sentence that seems particularly germane is: "The principal influence of the substrate upon the distribution of rooted vegetation is due to its physical texture rather than its chemical composition."
Needless to say...he goes on from there.<g>