Poster Details
FROM HILLSLOPES TO SURFACE WATERS: PATTERNS IN CO2 AND CH4 FLUXES FROM INTERMITTENT AND PERENNIAL WATERWAYS
Carbon dioxide (CO2) and methane (CH4) emissions from intermittent streams, areas where watercourses run dry, are often neglected in estimates of terrestrial and aquatic carbon fluxes. We estimated CO2 and CH4 emissions from two headwater stream corridors in different watersheds, including hillslopes, drybeds, and perennial surface waters, at Coweeta Hydrologic Lab, North Carolina. During June 2018, we sampled gas fluxes every ten meters along 145 m reaches of two streams. During August 2018, we returned to compare emissions from habitats within the stream corridors. Hillslopes had the highest CO2 fluxes of the three habitats (median=260 mmol m-2d-1, range 40-1300), followed by streams (median=126 mmol m-2d-1, range 13-1150) and drybeds (median=62 mmol m-2d-1, range 29-587). CH4 fluxes from drybeds and hillslopes (-0.3 - 0.4 mmol m-2d-1) were more variable than stream emissions (-0.1 - 0.2 mmol m-2d-1). Neither of the stream corridors was consistently a CH4 source. These results reinforce the need to include the variability of gas emissions within stream corridors in our studies of carbon dynamics. We will use these data to estimate corridor-scale CO2 and CH4 emissions for an improved understanding of intermittent and perennial stream carbon dynamics.
Sumaiya Rahman (Primary Presenter/Author), Virginia Tech, Sumaiya@vt.edu;
Erin Hotchkiss (Co-Presenter/Co-Author), Virginia Polytechnic Institute and State University (Virginia Tech), ehotchkiss@vt.edu;