Radiocarbon Analyses Quantify Peat Carbon Losses With Increasing Temperature in a Whole Ecosystem Warming Experiment

Climate warming is expected to accelerate peatland degradation and release rates of carbon dioxide (CO2) methane (CH4). Spruce Peatlands Responses Under Changing Environments an ecosystem-scale climate manipulation experiment, designed examine ecosystem response forcings. We examined whether heating up +9 °C 3 m-deep in a peat bog over 7-year period led higher C turnover CO2 CH4 emissions, by measuring 14C solid peat, dissolved organic (DOC), CH4, (DIC). DOC, major substrate for heterotrophic respiration, increased significantly with warming. There was no trend the DI14 ambient plots which remained similar their DO14 C. At +6.75 °C, DIC, product microbial initially resembled but became more depleted 7 years attributed shifts increasing importance phase as respiration quantified this shift via radiocarbon mass balance. The mass-balance model revealed increases peat-supported catotelm depths heated time relative enclosures, from baseline 20%–25% 35%–40% plots. find that stimulates microorganisms respire ancient C, deposited under prior (cooler) conditions. This apparent destabilization large reservoir has implications peatland-climate feedbacks especially if balance tipped net sink source.