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Little is known about how hydrologic processes along the terrestrial-aquatic interface in wetland dominated landscapes influence carbon dynamics, particularly regarding soil-derived dissolved organic matter (DOM) transport and transformation. To understand the role of different soil horizons as potential sources of DOM to wetland systems, we measured water soluble organic matter (WSOM) in soil horizons collected from upland to wetland transects at four Delmarva Bay wetlands. The Delmarva Bays used in this study are located on property managed by The Nature Conservancy on the Delmarva Peninsula in the eastern United States. Transects ranged from 25 – 45 m in length beginning from a monitoring well in the wetland center to an upland monitoring well. Each transect had four points (Upland, Transition, Edge, and Wetland). Soils were sampled in the late winter (January 17 and March 10) and autumn (September 21 and November 1) of 2020. Soils were sampled by horizon to a depth of approximately 50 cm at each transect point. WSOM extracted in the laboratory was analyzed for WSOM concentration, reported as Water Soluble Organic Carbon (mg WSOC / g soil). WSOM absorbance and fluorescence data were used to calculate composition metrics, providing insight to organic matter sources and chemical characteristics. WSOM fluorescence excitation-emission matrices were evaluated using the 13 component Cory and McKnight (2005) PARAFAC model. Extracted leaf litter, surface water, and groundwater samples were collected in addition to soil samples for the purpose of comparing WSOM to DOM end-members along the Delmarva Bay terrestrial-aquatic continuum. Continuous water level data, averaged to a daily time-step, was collected over the 2020 water year (October 1, 2019 to September 30, 2020) in previously established wetland and upland monitoring wells. The hydrologic conditions (e.g. mean water level, number of saturation events, duration of saturation) at each transect point were characterized by assuming a linear water table between wetland and upland monitoring wells. Hydrologic conditions and WSOM data were used to estimate potential realized DOM release in Wetland and Upland O horizons.