Tree species diversity affects decomposition through modified micro-environmental conditions across European forests

TY - JOUR

T1 - Tree species diversity affects decomposition through modified micro-environmental conditions across European forests

AU - Joly, Francois-Xavier

AU - Milcu, Alexandru

AU - Scherer-Lorenzen, Michael

AU - Jean, Loreine Katia

AU - Bussotti, Filippo

AU - Dawud, Seid Muhie

AU - Müller, Sandra

AU - Pollastrini, Martina

AU - Raulund-Rasmussen, Karsten

AU - Vesterdal, Lars

AU - Hättenschwiler, Stephan

PY - 2017/5/1

Y1 - 2017/5/1

N2 - Different tree species influence litter decomposition directly through species-specific litter traits, and indirectly through distinct modifications of the local decomposition environment. Whether these indirect effects on decomposition are influenced by tree species diversity is presently not clear. We addressed this question by studying the decomposition of two common substrates, cellulose paper and wood sticks, in a total of 209 forest stands of varying tree species diversity across six major forest types at the scale of Europe. Tree species richness showed a weak but positive correlation with the decomposition of cellulose but not with that of wood. Surprisingly, macroclimate had only a minor effect on cellulose decomposition and no effect on wood decomposition despite the wide range in climatic conditions among sites from Mediterranean to boreal forests. Instead, forest canopy density and stand-specific litter traits affected the decomposition of both substrates, with a particularly clear negative effect of the proportion of evergreen tree litter. Our study suggests that species richness and composition of tree canopies modify decomposition indirectly through changes in microenvironmental conditions. These canopy-induced differences in the local decomposition environment control decomposition to a greater extent than continental-scale differences in macroclimatic conditions.

AB - Different tree species influence litter decomposition directly through species-specific litter traits, and indirectly through distinct modifications of the local decomposition environment. Whether these indirect effects on decomposition are influenced by tree species diversity is presently not clear. We addressed this question by studying the decomposition of two common substrates, cellulose paper and wood sticks, in a total of 209 forest stands of varying tree species diversity across six major forest types at the scale of Europe. Tree species richness showed a weak but positive correlation with the decomposition of cellulose but not with that of wood. Surprisingly, macroclimate had only a minor effect on cellulose decomposition and no effect on wood decomposition despite the wide range in climatic conditions among sites from Mediterranean to boreal forests. Instead, forest canopy density and stand-specific litter traits affected the decomposition of both substrates, with a particularly clear negative effect of the proportion of evergreen tree litter. Our study suggests that species richness and composition of tree canopies modify decomposition indirectly through changes in microenvironmental conditions. These canopy-induced differences in the local decomposition environment control decomposition to a greater extent than continental-scale differences in macroclimatic conditions.

U2 - 10.1111/nph.14452

DO - 10.1111/nph.14452

M3 - Journal article

C2 - 28181238

SN - 0028-646X

VL - 214

SP - 1281

EP - 1293

JO - New Phytologist

JF - New Phytologist

IS - 3

ER -