Global meta-analysis of wood decomposition rates: a role for trait variation among tree species?
The carbon flux from woody debris, a crucial uncertainty within global carbon-climate models, is simultaneously affected by climate, site environment and species-based variation in wood quality. In the first global analysis attempting to explicitly tease out the wood quality contribution to decomposition, we found support for our hypothesis that, under a common climate, interspecific differences in wood traits affect woody debris decomposition patterns. A meta-analysis of 36 studies from all forested continents revealed that nitrogen, phosphorus, and C : N ratio correlate with decomposition rates of angiosperms. In addition, gymnosperm wood consistently decomposes slower than angiosperm wood within common sites, a pattern that correlates with clear divergence in wood traits between the two groups. New empirical studies are needed to test whether this difference is due to a direct effect of wood trait variation on decomposer activity or an indirect effect of wood traits on decomposition microsite environment. The wood trait-decomposition results point to an important role for changes in the wood traits of dominant tree species as a driver of carbon cycling, with likely feedback to atmospheric CO(2) particularly where angiosperm species replace gymnosperms regionally. Truly worldwide upscaling of our results will require further site-based multi-species wood trait and decomposition data, particularly from low-latitude ecosystems.
Weedon
James T
JT
Department of Systems Ecology, Institute of Ecological Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands. james.weedon@falw.vu.nl
Cornwell
William K
WK
Cornelissen
Johannes H C
JH
Zanne
Amy E
AE
Wirth
Christian
C
Coomes
David A
DA
D001673:Biodegradation, Environmental; D002244:Carbon / Q000378:metabolism*; D002980:Climate; D008031:Lignin / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism; D013045:Species Specificity; D014197:Trees / Q000378:metabolism*; D014934:Wood / Q000378:metabolism*
D010758:Phosphorus; D002244:Carbon; D008031:Lignin; D009584:Nitrogen