|Title||Widespread coupling between the rate and temperature sensitivity of organic matter decay|
|Publication Type||Journal Article|
|Year of Publication||2010|
|Authors||Craine, JM, Fierer, N, McLauchlan, KK|
|Keywords||Biogeochemistry, Microbial ecology|
Microbial breakdown of soil organic matter influences the potential for terrestrial ecosystems to sequester carbon, and the amount of carbon dioxide released to the atmosphere1, 2, 3, 4. Predicting the sensitivity of microbial decomposition to temperature change is therefore critical to predicting future atmospheric carbon dioxide concentrations and feedbacks to anthropogenic warming5. According to enzyme kinetics, the more biogeochemically recalcitrant the organic matter, the greater the temperature sensitivity of microbial respiration6, 7, 8. Here, we measured the temperature sensitivity of microbial respiration in soils from 28 sites in North America, ranging from Alaska to Puerto Rico, to test the generality of this principle. We show that the lower the rate of respiration at a reference temperature of 20 °C—and thus the more biogeochemically recalcitrant the organic matter—the greater the temperature sensitivity of soil respiration. We compiled our findings with those from other studies, encapsulating a range of environments, and show that this relationship holds across multiple scales and soil types. Although physico-chemical protection of soil organic matter and substrate availability will also influence the temperature sensitivity of decomposition, we suggest that biogeochemically recalcitrant organic matter will respond the most sensitively to anticipated warming.