The impact of herbivore exclusion on carbon cycling in created wetlands

Session: Poster Session

Briana Burt, Rochester Institute of Technology , [email protected]
Kimberly Lodge, Rochester Institute of Technology, [email protected]
Delanie Spangler, Rochester Institute of Technology, [email protected]
Benjamin Hamilton, Rochester Institute of Technology, [email protected]
Evan Squier, Rochester Institute of Technology, [email protected]
Christy Tyler, Rochester Institute of Technology, [email protected]
Carmody McCalley, Rochester Institute of Technology, [email protected]

Abstract

Wetlands provide valuable ecosystem services and are increasingly threatened by urbanization, prompting the need for created wetlands. Replicating the functions of natural wetlands has proven difficult and created wetlands often have lower plant diversity and productivity. This study explores the implementation of herbivore exclusion as a management approach in two created wetlands in Western, NY. Changes in carbon gas fluxes were quantified in plots with and without the influence of large grazers. Fluxes of methane (CH₄) and carbon dioxide (CO₂) were measured in the light and dark and soil incubations were conducted to asses anaerobic CH₄ and CO₂ production potentials and rates of CH₄ oxidation. When grazers were excluded from plots, vegetation cover and biomass increased, resulting in enhanced photosynthesis and respiration and significantly increasing net primary productivity. In contrast, grazed plots emitted more CH_4, likely due to reduced plant-mediated oxygen transport, leading to decreased rates of methane oxidation. Laboratory incubations support the hypothesis that decreased CH₄ fluxes when grazers are excluded are related to increases in CH₄ oxidation not changes in CH₄ production. These results suggest that grazers play an important role in wetland vegetation dynamics and shift greenhouse gas production in wetlands.