Hougham, A. L., University of South Carolina, Columbia, SC, USA, ahougham@geol.sc.edu
Wilson, A. M., University of South Carolina, Columbia, SC, USA, awilson@geol.sc.edu

SALT MARSH GROUNDWATER DYNAMICS DELINEATED USING GROUNDWATER TEMPERATURE AS A TRACER

Knowledge of groundwater-driven exchange of water, solutes, and nutrients between salt marsh estuaries and shelf waters is important for understanding global solute budgets and such phenomena as acute salt marsh dieback. Here we investigated salt marsh groundwater dynamics, using heat as a tracer, as part of a larger field and modeling study. Seven piezometer nests were installed in two transects at an acute marsh dieback site within the North Inlet NERR, Georgetown, South Carolina. Each nest contains three piezometers screened at depths of 1 m, 2 m, and 4 m. Temperature was recorded at 10 minute intervals in the piezometers beginning August 2006 and ranged from 9 – 36ºC over a one-year period. A comparison of observed temperatures and results of a 1-D conductive heat flow model indicates that groundwater temperatures were primarily conductive from January through September 2007. However, the piezometer temperature record from October 2006 suggests vertical advection and possible density-driven overturn. If occurring on a marsh-wide basis, such flow could provide a significant pulse of nutrients and solutes to coastal surface waters.

Oral presentation

Presentation is given by student: Yes
Session #:089
Date: 03-03-2008
Time: 17:00