TY - JOUR

T1 - Disentangling drivers of litter decomposition in a multi-continent network of tree diversity experiments

AU - Desie, Ellen

AU - Zuo, Juan

AU - Verheyen, Kris

AU - Djukic, Ika

AU - Van Meerbeek, Koenraad

AU - Auge, Harald

AU - Barsoum, Nadia

AU - Baum, Christel

AU - Bruelheide, Helge

AU - Eisenhauer, Nico

AU - Feldhaar, Heike

AU - Ferlian, Olga

AU - Gravel, Dominique

AU - Jactel, Hervé

AU - Schmidt, Inger Kappel

AU - Kepfer-Rojas, Sebastian

AU - Meredieu, Céline

AU - Mereu, Simone

AU - Messier, Christian

AU - Morillas, Lourdes

AU - Nock, Charles

AU - Paquette, Alain

AU - Ponette, Quentin

AU - Reich, Peter B.

AU - Roales, Javier

AU - Scherer-Lorenzen, Michael

AU - Seitz, Steffen

AU - Schmidt, Anja

AU - Stefanski, Artur

AU - Trogisch, Stefan

AU - Van Halder, Inge

AU - Weih, Martin

AU - Williams, Laura J.

AU - Yang, Bo

AU - Muys, Bart

N1 - Copyright © 2022. Published by Elsevier B.V.

PY - 2023

Y1 - 2023

N2 - Litter decomposition is a key ecosystem function in forests and varies in response to a range of climatic, edaphic, and local stand characteristics. Disentangling the relative contribution of these factors is challenging, especially along large environmental gradients. In particular, knowledge of the effect of management options, such as tree planting density and species composition, on litter decomposition would be highly valuable in forestry. In this study, we made use of 15 tree diversity experiments spread over eight countries and three continents within the global TreeDivNet network. We evaluated the effects of overstory composition (tree identity, species/mixture composition and species richness), plantation conditions (density and age), and climate (temperature and precipitation) on mass loss (after 3 months and 1 year) of two standardized litters: high-quality green tea and low-quality rooibos tea. Across continents, we found that early-stage decomposition of the low-quality rooibos tea was influenced locally by overstory tree identity. Mass loss of rooibos litter was higher under young gymnosperm overstories compared to angiosperm overstories, but this trend reversed with age of the experiment. Tree species richness did not influence decomposition and explained almost no variation in our multi-continent dataset. Hence, in the young plantations of our study, overstory composition effects on decomposition were mainly driven by tree species identity on decomposer communities and forest microclimates. After 12 months of incubation, mass loss of the high-quality green tea litter was mainly influenced by temperature whereas the low-quality rooibos tea litter decomposition showed stronger relationships with overstory composition and stand age. Our findings highlight that decomposition dynamics are not only affected by climate but also by management options, via litter quality of the identity of planted trees but also by overstory composition and structure.

AB - Litter decomposition is a key ecosystem function in forests and varies in response to a range of climatic, edaphic, and local stand characteristics. Disentangling the relative contribution of these factors is challenging, especially along large environmental gradients. In particular, knowledge of the effect of management options, such as tree planting density and species composition, on litter decomposition would be highly valuable in forestry. In this study, we made use of 15 tree diversity experiments spread over eight countries and three continents within the global TreeDivNet network. We evaluated the effects of overstory composition (tree identity, species/mixture composition and species richness), plantation conditions (density and age), and climate (temperature and precipitation) on mass loss (after 3 months and 1 year) of two standardized litters: high-quality green tea and low-quality rooibos tea. Across continents, we found that early-stage decomposition of the low-quality rooibos tea was influenced locally by overstory tree identity. Mass loss of rooibos litter was higher under young gymnosperm overstories compared to angiosperm overstories, but this trend reversed with age of the experiment. Tree species richness did not influence decomposition and explained almost no variation in our multi-continent dataset. Hence, in the young plantations of our study, overstory composition effects on decomposition were mainly driven by tree species identity on decomposer communities and forest microclimates. After 12 months of incubation, mass loss of the high-quality green tea litter was mainly influenced by temperature whereas the low-quality rooibos tea litter decomposition showed stronger relationships with overstory composition and stand age. Our findings highlight that decomposition dynamics are not only affected by climate but also by management options, via litter quality of the identity of planted trees but also by overstory composition and structure.

U2 - 10.1016/j.scitotenv.2022.159717

DO - 10.1016/j.scitotenv.2022.159717

M3 - Journal article

C2 - 36302436

VL - 857

JO - Science of the Total Environment

JF - Science of the Total Environment

SN - 0048-9697

M1 - 159717

ER -