Impacts of Evaporation-Induced Groundwater Upwelling on Mixing Dynamics in Shallow Wetlands
Document Type
Article
Publication Date
8-16-2023
Abstract
Groundwater mixing dynamics play a crucial role in the biogeochemical cycling of shallow wetlands. In this paper, we conducted groundwater simulations to investigate the combined effects of evaporation and local heterogeneity on mixing dynamics in shallow wetland sediments. The results show that evaporation causes groundwater and solutes to upwell from deep sediments to the surface. As the solute reaches the surface, evaporation enhances the accumulation of the solute near the surface, resulting in a higher solute concentration than in deep sediments. Mapping of flow topology reveals that local heterogeneity generates spatially varied mixing patterns mainly along preferential flow pathways. The upwelling of groundwater induced by surface evaporation through heterogeneous sediments is likely to create distinct mixing hotspots that differ spatially from those generated by lateral preferential flows driven by large-scale hydraulic gradients, which enhances the overall mixing in the subsurface. These findings have strong implications for biogeochemical processing in wetlands.
Identifier
85166737847 (Scopus)
Publication Title
Geophysical Research Letters
External Full Text Location
https://doi.org/10.1029/2023GL104642
e-ISSN
19448007
ISSN
00948276
Issue
15
Volume
50
Grant
2130595
Fund Ref
National Science Foundation
Recommended Citation
Geng, Xiaolong; Boufadel, Michel C.; Li, Hailong; Na Nagara, Viravid; and Lee, Kenneth, "Impacts of Evaporation-Induced Groundwater Upwelling on Mixing Dynamics in Shallow Wetlands" (2023). Faculty Publications. 1518.
https://digitalcommons.njit.edu/fac_pubs/1518