Pedogenesis in terrestrial versus aquatic environments is controlled by a differing set of soil forming factors, producing soils of notably distinct physical and chemical characteristics. While pedological processes operating in terrestrial soils have received consistent attention by past and present-day investigators, pedogenesis in the subaqueous environment has only very recently come under scientific scrutiny. Understanding how soils are formed within aquatic environments will provide valuable information regarding the presence and distribution of distinct soils. The main objective of our research is to describe and document the physical and chemical equilibrium conditions of soils in similar geographic areas which have been subject to pedogenic processes characteristic of the terrestrial and aquatic environment. We selected five transects crossing the terrestrial-aquatic interface along the slow-moving (<1m/s) spring-fed Chassahowitzka River on the Gulf Coast of Florida. Along each transect, soils representative of terrestrial, subaqueous, and the terrestrial-subaqueous interface were described and classified according to USDA Soil Taxonomy. Soil samples were analyzed for organic matter (OM) content, pH, particle-size distribution, and C/N ratio. Environmental factors affecting soil formation were also quantified at each site including climatic variables, landscape/bathymetric position, soil/water/air temperature, water velocity, salinity, and dominant vegetation type. The physical and chemical characteristics of the soils were compared both within and between terrestrial and subaqueous environments. We expect to discover significant differences in pedogenesis and equilibrium conditions between terrestrial and subaqueous soils. These findings will provide a foundation for future research addressing the biogeochemical roles of distinct types of terrestrial and subaqueous soils in watershed-scale elemental cycling.