Climate change accelerates global forest deadwood dynamics

Abstract The development of future forest deadwood is uncertain, as processes related to deadwood formation (i.e., tree growth and mortality) as well as deadwood decomposition are simultaneously impacted by climate change. To elucidate future deadwood dynamics under scenarios of climate change, we combined a map of current global deadwood stocks with tree growth and mortality rates simulated by five dynamic global vegetation models and a function of climate-dependent deadwood decomposition derived from a global experiment. Deadwood dynamics intensified throughout the 21st century, with both inputs and outputs to global deadwood carbon pools increasing as a result of climate change. However, deadwood formation increased on average 5.0% more strongly than decomposition, suggesting an overall increase in global deadwood in the coming decades. As deadwood is an important nexus of forest carbon and biodiversity, we call for a stronger focus on deadwood in forest policy and management.