Back from the past? Assessing potential of relict, hydric soils for wetland and floodplain restorations

Co-authors: Shreeram Inamdar, Marc Peipoch, Jinjun Kan

Abstract: This study will characterize the biogeochemical and microbial attributes of buried, relict hydric soils and how they can be leveraged to enhance water quality and ecological health of contemporary floodplain and wetland restorations. Currently, no guidance exists on the use of historic hydric soils in ecosystem restorations and they are typically removed from restoration sites. In absence of such guidance, we may be losing valuable native microbiome and seedbanks at restoration sites. We will analyze >10 hydric soil sites in the mid-Atlantic and compare their attributes against four representative wetland soils. Analysis includes multiple metrics: 14C age; concentrations of organic carbon, total nitrogen (N), nitrate-N, ammonium-N; N process rates (denitrification, nitrification, and mineralization); and microbial functional genes for denitrification (nosZ) and nitrification (AoA and AoB). Soils have been placed/incubated on the surface of an existing floodplain restoration site for one year to assess how the hydric soils change/recover following “daylighting” to the surface. Analysis will be performed for both pre and post incubations of hydric and contemporary wetland soils. This study will provide first important insights into how hydric soils would behave if included in wetland restorations and pave the way for greater considerations of soil health in our ecosystem restorations. This study will be performed in close collaboration with restoration practitioners so that results are immediately transferable and robust and practical best practices can be developed.

Status: Fieldwork and data collection initiated/in progress. 

Funding: This study was funded by National Science Foundation Hydrologic Sciences grant #1929747