Tree species richness increases ecosystem carbon storage in subtropical forests

• Published in: Proceedings of the Royal Society. B, Biological sciences Vol. 285; no. 1885; p. 20181240
• Main Authors: Liu, Xiaojuan, Trogisch, Stefan, He, Jin-Sheng, Niklaus, Pascal A., Bruelheide, Helge, Tang, Zhiyao, Erfmeier, Alexandra, Scherer-Lorenzen, Michael, Pietsch, Katherina A., Yang, Bo, Kühn, Peter, Scholten, Thomas, Huang, Yuanyuan, Wang, Chao, Staab, Michael, Leppert, Katrin N., Wirth, Christian, Schmid, Bernhard, Ma, Keping
• Format: Journal Article
• Language: English
• Published: England The Royal Society 22.08.2018
• Subjects: Biodiversity; Carbon Sequestration; China; Ecology; Forests; Time Factors; Trees - physiology; China; carbon storage; BEF-China; carbon flux; evergreen broad-leaved forest; ecosystem functioning; forest biodiversity
• ISSN: 0962-8452; 1471-2954; 1471-2954
• DOI: 10.1098/rspb.2018.1240

Forest ecosystems are an integral component of the global carbon cycle as they take up and release large amounts of C over short time periods (C flux) or accumulate it over longer time periods (C stock). However, there remains uncertainty about whether and in which direction C fluxes and in particular C stocks may differ between forests of high versus low species richness. Based on a comprehensive dataset derived from field-based measurements, we tested the effect of species richness (3–20 tree species) and stand age (22–116 years) on six compartments of above- and below-ground C stocks and four components of C fluxes in subtropical forests in southeast China. Across forest stands, total C stock was 149 ± 12 Mg ha −1 with richness explaining 28.5% and age explaining 29.4% of variation in this measure. Species-rich stands had higher C stocks and fluxes than stands with low richness; and, in addition, old stands had higher C stocks than young ones. Overall, for each additional tree species, the total C stock increased by 6.4%. Our results provide comprehensive evidence for diversity-mediated above- and below-ground C sequestration in species-rich subtropical forests in southeast China. Therefore, afforestation policies in this region and elsewhere should consider a change from the current focus on monocultures to multi-species plantations to increase C fixation and thus slow increasing atmospheric CO 2 concentrations and global warming.