Abstract

Seasonal wetlands comprise a minor fraction of the Southern Piedmont, and yet play a major role in connecting upland systems to river networks. Historic erosion from upland agriculture has altered this degree of hydrologic connectivity, causing floodplains to accrete significantly with 1 to 2 meters of eroded sediment. Here, we investigate the impact of this accelerated sedimentation on oxidation-reduction dynamics in a Piedmont bottomland forest. First, we found the lowering of soil redox potential to lag winter wet-up, and attribute this delay to low energy source from organic matter. Second, we determined that sedimentation has dampened the expression of seasonal oxidation-reduction cycles in the mid- to upper-reaches of Piedmont floodplains by creating terrace environments with lower hydrologic connectivity. Our results suggest that seasonal wetlands in the Southern Piedmont, naturally slow to enter reductive conditions, have become even less reductive in response to historic sedimentation.

Citation

Wade, Anna, Daniel Richter (2019): Saturated but Not Yet Suffocated: Seasonal Oxidation-Reduction Dynamics in Southern Piedmont Floodplains. ASA-CSSA-SSSA International Annual Meeting, 10-13 Nov. 2019, San Antonio, Texas.

This Paper/Book acknowledges NSF CZO grant support.