Effects of subsurface soil characteristics on wetland–groundwater interaction in the coastal plain of the Chesapeake Bay watershed. Issue 2 (28th November 2018)

• Record Type: Journal Article
• Authors: Lee, Sanghcul; McCarty, Gregory W.; Moglen, Glenn E.; Lang, Megan W.; Sadeghi, Ali M.; Green, Timothy R.; Yeo, In‐Young; Rabenhorst, Martin C.
• Is Part Of: Hydrological processes. Volume 33:Issue 2(2019)
• Page Start: 305
• Page End: 315
• Publication Date: 2018-11-28
• Subjects: Chesapeake Bay watershed (CBW) -- depressional wetlands -- groundwater level (GWL) -- hydroperiod -- subsurface soil characteristics -- surface water level (SWL); Hydrology -- Periodicals; Hydrology -- Research -- Periodicals; Hydrologic models -- Periodicals; Hydrological forecasting -- Periodicals; 631.432
• DOI: 10.1002/hyp.13326
• Languages: English
• ISSNs: 0885-6087

Abstract

Abstract: Ecosystem services provided by depressional wetlands on the coastal plain of the Chesapeake Bay watershed (CBW) have been widely recognized and studied. However, wetland–groundwater interactions remain largely unknown in the CBW. The objective of this study was to examine the vertical interactions of depressional wetlands and groundwater with respect to different subsurface soil characteristics. This study examined two depressional wetlands with a low‐permeability and high‐permeability soil layer on the coastal plain of the CBW. The surface water level (SWL) and groundwater level (GWL) were monitored over 1 year from a well and piezometer at each site, respectively, and those data were used to examine the impacts of subsurface soil characteristics on wetland–groundwater interactions. A large difference between the SWL and GWL was observed at the wetland with a low‐permeability soil layer, although there was strong similarity between the SWL and GWL at the wetland with a high‐permeability soil layer. Our observations also identified a strong vertical hydraulic gradient between the SWL and GWL at the wetland with a high‐permeability soil layer relative to one with a low‐permeability soil layer. The hydroperiod (i.e., the total time of surface water inundation or saturation) of the wetland with a low‐permeability soil layer appeared to rely on groundwater less than the wetland with a high‐permeability soil layer. The findings showed that vertical wetland–groundwater interactions varied with subsurface soil characteristics on the coastal plain of the CBW. Therefore, subsurface soil characteristics should be carefully considered to anticipate the hydrologic behavior of wetlands in this region.