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Temperature affects the efficiency of carbon preservation through several related mechanisms. Firstly, biological processes such as decomposition generally slow down at cooler temperatures, as demonstrated for multiple indices of decomposition including litter decay, soil enzyme activities, biological oxygen demand, CO₂ and CH₄ production and emissions to the atmosphere, and the hydrologic export of dissolved organic and inorganic carbon (Freeman et al., 2001; Kadlec & Reddy, 2001; Miller et al., 2001; Neubauer & Anderson, 2003; Segers, 1998; Treat et al., 2014). Rates of peat decomposition are negligible at temperatures below 0°C and increase sharply as the liquid water content increases in warmed permafrost soils (Dioumaeva et al., 2003). Secondly, temperature sensitivities can vary within the consortium of decomposers, with subsequent effects on the efficiency of carbon mineralization. Terminal metabolizers (e.g., SO₄^2– reducers) can be more sensitive to temperature than are fermenters, thus leading to the accumulation of fermentation products (e.g., acetate) at lower temperatures and the limitation of terminal metabolism by the (low) abundance of these compounds at higher temperatures (e.g., Fey & Conrad, 2003; Weston & Joye, 2005). Indeed, in some high‐latitude wetlands, acetate is the terminal end product of anaerobic decomposition (Duddleston et al., 2002; M. E. Hines et al., 2001). Thirdly, changing temperatures can result in vegetation shifts that change the nature of organic matter inputs to the soil. Along a 40‐year progression of permafrost thaw, rates of potential CO₂ and CH₄ production were highest in the sites that had been thawed the longest, a difference mediated by the indirect role of temperature in changing vegetation assemblages and, therefore, the chemistry of organic matter inputs to the soil (Hodgkins et al., 2014). While cold temperatures contribute to wetland carbon preservation, the existence of tropical peatlands is strong evidence that temperature is not the only driver (Hodgkins et al., 2018).