Soil Carbon Across the Wetland Landscape: Forms, Functions, and Processes at Differing Scales and Settings.

Soil carbon takes many forms in the wetland environment. These forms change depending on the wetland landscape setting. These settings extend across the landscape from upland wetlands, to riparian zones that connect to the larger rivers and marshes, and eventually to the subaqueous soil systems in either estuarine or lacustrine settings. In this paper, we illustrate the various forms of carbon that appear in riparian, salt marsh, and estuarine subtidal wetland settings. We will elucidate the associated processes that result in these forms; and discuss how the forms and processes relate to the range of functions that are associated with wetlands. The discussion will focus on soil carbon studies related to flux, storage, sequestration, denitrification, sedimentation, pedogenesis, and hydric soils. Our scales range across a continuum from microscopic (thin sections and pollen grains), to hand-held specimens, to pedon level investigations, and finally scaling up to landscape level.