The flux of CO2 from wood decomposition is a fundamental component of
the global carbon cycle, but the impact of human-induced changes in
temperature and nutrients on this flux is not well understood. We
examined the effects of nitrogen and phosphorous addition on the
temperature-dependence of CO2 fluxes from wood with differing traits
(angiosperm and gymnosperm) over a three-year period. Results showed
that CO2 fluxes were driven primarily by phosphorus and only secondarily
by nitrogen, and that the effect of phosphorus was mediated by wood
traits, with a greater increase in gymnosperms than angiosperms. The
temperature dependences of CO2 fluxes were remarkably constant across
nutrient levels, consistent with metabolic scaling theory hypotheses.
These results suggest that phosphorus availability is a key driver of
variation in wood CO2 fluxes, but has a limited impact on the
temperature dependence. Our findings can inform predictions for wood
carbon fluxes in a changing climate.