Tree leaf and root traits mediate soil faunal contribution to litter decomposition across an elevational gradient

1.Plant litter decomposition is key to carbon and nutrient cycling in terrestrial ecosystems. Soil fauna are important litter decomposers, but how their contribution to decomposition changes with alterations in plant composition and climate is not well established.

2.Here we quantified how soil mesofauna affect decomposition rate interactively with climate and leaf and root traits. We conducted an in situ decomposition experiment using eight dominant tree species per forest site across four elevations (50, 400, 600 and 1000 m above sea level) in northern Japan. We used litterbags with different mesh sizes to control litter accessibility to soil mesofauna.

3.We found stronger effects of plant litter quality on both decomposition rates and faunal contribution thereto, and perhaps of local variation in soil nutritional and moisture regimes, than climatic effects of elevation. This suggests that changing climate likely alters forest litter decomposition rates indirectly through shifts...