Sigma Xi Poster Competition
Gas Flux Rates of Wetland Soil Types During Inundation and NO3 - : Bottomland Hardwood and Cypress Slough
Academic Level at Time of Presentation
Senior
Major
Wildlife Biology
2nd Student Academic Level at Time of Presentation
Junior
2nd Student Major
Biology
2nd Student Minor
Wildlife Biology
List all Project Mentors & Advisor(s)
Jessica Moon
Presentation Format
Poster Presentation
Abstract/Description
Wetland soils play a critical role in nutrient cycling and regulating greenhouse gases. The ability of wetlands to both release and uptake greenhouse gases is affected by several factors, including hydrology, organic matter, soil texture, and microbial activity. Bottomland hardwood forests, which are typically found in floodplains, often experience fluctuations in water levels, with flooding, leading to changes in delivery of nutrients (e.g., nitrate – NO3 - ) and oxygen availability in the soil. In contrast, cypress sloughs (i.e., channels within the bottomland forests) are characterized by more consistent inundation with lower percentages of carbon. Flooding events can fuel denitrification, producing nitrous oxide (N₂O) and dinitrogen (N2). We investigated how inundation and subsequently NO3 - additions affected N₂O fluxes from these two wetland soil types: bottomland hardwood (n = 3) and cypress slough (n = 3). Gas flux measurements were collected (LI-COR gas analyzer) across 10-hour incubations from cores of the top 5 cm of soil for both treatments. Although mean N₂O flux rates were not significantly different between bottomland forests and slough soil cores, the bottomland hardwood soil was more variable than the cypress slough soil, with one core reaching N₂O flux rates of 79,405.544 umol during simulated inundation and 30,517.824 umol during NO3 - addition. More extensive testing will be needed to explain the variability in fluxes within the bottomland hardwood site.
Spring Scholars Week 2025
Sigma Xi Poster Competition
Gas Flux Rates of Wetland Soil Types During Inundation and NO3 - : Bottomland Hardwood and Cypress Slough
Wetland soils play a critical role in nutrient cycling and regulating greenhouse gases. The ability of wetlands to both release and uptake greenhouse gases is affected by several factors, including hydrology, organic matter, soil texture, and microbial activity. Bottomland hardwood forests, which are typically found in floodplains, often experience fluctuations in water levels, with flooding, leading to changes in delivery of nutrients (e.g., nitrate – NO3 - ) and oxygen availability in the soil. In contrast, cypress sloughs (i.e., channels within the bottomland forests) are characterized by more consistent inundation with lower percentages of carbon. Flooding events can fuel denitrification, producing nitrous oxide (N₂O) and dinitrogen (N2). We investigated how inundation and subsequently NO3 - additions affected N₂O fluxes from these two wetland soil types: bottomland hardwood (n = 3) and cypress slough (n = 3). Gas flux measurements were collected (LI-COR gas analyzer) across 10-hour incubations from cores of the top 5 cm of soil for both treatments. Although mean N₂O flux rates were not significantly different between bottomland forests and slough soil cores, the bottomland hardwood soil was more variable than the cypress slough soil, with one core reaching N₂O flux rates of 79,405.544 umol during simulated inundation and 30,517.824 umol during NO3 - addition. More extensive testing will be needed to explain the variability in fluxes within the bottomland hardwood site.