Ecohydrology of a Floodplain Forest: Relationships Between Evapotranspiration, Vegetation, and Topography at Congaree National Park, South Carolina

Ecohydrology of a Floodplain Forest: Relationships Between Evapotranspiration, Vegetation, and Topography at Congaree National Park, South Carolina

Congaree National Park supports high biodiversity and provides ecosystem services for the surrounding area in the floodplain wetland system, especially in the bottomland hardwood forests which contain some of the last remaining old-growth stands in the eastern U.S. Maintaining the hydraulic functions of this ecosystem is essential not only for the conservation of biodiversity, but also for the ecosystem services it provides, such as nitrification, denitrification, decomposition, removal of organic carbon, and phosphorous uptake and sorption. Because management practices of the park depend on understanding the area‟s hydrology, past research has been performed to analyze the flooding of Congaree River. However, not much has been done to better understand groundwater movement through the floodplain sediments in the Congaree River Valley. The goal of this project is to quantify interactions between the shallow unconfined aquifer and local vegetation surrounding eight piezometers in the Congaree Observation Well Network at Congaree National Park through calculating and comparing evapotranspiration rates, specific yield, vegetation diversity and basal area, and microtopography. Data on groundwater response to storm events, diurnal signals caused by evaporation and transpiration in the forest, vegetation community structure, and local topography were compared to better understand the role of these factors on vegetation water demand in this wetland-dominated system.