Baptiste Joseph Wijas, William K Cornwell, Jeff R Powell , Brad Oberle, Amy E Zanne

● Deadwood represents globally important carbon, nitrogen, and phosphorus pools. Current wood nutrient dynamics models are extensions of those developed for leaf litter decomposition. However, tissue structure and dominant decomposers differ between deadwood and litter, and recent evidence suggests that decomposer stoichiometry in combination with litter quality may affect nutrient release.

 ● We quantified decomposition and release of carbon and nutrients from wood for two stem sizes of 22 tree species in a phosphorus-limited temperate forest near Sydney, Australia, and compared these to estimates from leaf litter literature.

● Following theory, nitrogen and phosphorus accumulated during early decomposition, but began to decline earlier than expected from work on leaves. Deadwood converged on higher carbon:nitrogen (50) and nitrogen:phosphorus (80) ratios than in leaf litter studies. Carbon:nitrogen at which nitrogen was released was higher in large stems (~135) than small stems (~95); both being higher than leaf litter.

● Drawing from the literature, these differences in nitrogen and phosphorus dynamics may be due to the identity of wood decomposers. Carbon:nitrogen of wood decomposers is higher than mean carbon:nitrogen of leaf litter decomposers, and this difference in stoichiometry may have important flow-on effects for nutrient cycles in forests.