Soil flux (CO2, CH4), soil temperature, and soil moisture measurements at the Great Dismal Swamp National Wildlife Refuge (2015 - 2017)

We identified nine study site locations, representing three mature vegetation communities [Atlantic White Cedar (desired community), tall pine pocosin (desired community), and red maple/black gum mixed (undesired community)] with typical water depth within each vegetation type. All measurements were replicated three times (3 vegetation types x 3 replicates = 9 sites total). We installed four flux chambers at each site to collect GHG fluxes from all nine sites. We measured CO2 and CH4 using a Los Gatos Research Ultra Portable Greenhouse Gas Analyzer and two-part 760 cm2 flux chambers (chamber base remained in situ; chamber top was placed on the bottom only when sampling). We checked the gas fluxes on a monthly time-table for 24 months (May 2015 through April 2017) measuring PPM CO2 and CH4 for ten minutes at each chamber. Monthly measurements were also taken for soil temperature and soil moisture. Soil temperature was recorded using a digital thermometer and soil moisture was recorded by measuring soil water content by mass using gravimetric soil moisture protocols at each site.