Some chemical aspects of wetland ecology

The chemical properties of fen and bog soils are examined in relation to ion supply from the mineral soil and from the atmosphere. As the influence of the mineral soil wanes through accumulation of org3nic material, exchangeable hydrogen ions replace exchangeable metallic cations upon the adsorptive complexes of peat deposits, the level of dissolved calcium in peat pools declines to less than 2 mg./l., and acidity rises very sharply--with pH often falling below 4. The source of this acidity may be oxidation of organic sulphur compounds in the peat, air pollution by sulphuric acid, or displacement of adsorbed hydrogen ions by metallic cations supplied through atmospheric precipitation~ Weather conditions and geographical location are shown to have a considerable effect upon the chemistry of rain and bog waters. The productivity of the plant cover of fens and bogs is shown to be related in some degree to the balance between silt and atmospheric precipitation assources of nutrients.