Contrasting effects of defaunation on aboveground carbon storage across the global tropics

• Published in: Nature communications Vol. 7; no. 1; p. 11351
• Main Authors: Osuri, Anand M, Ratnam, Jayashree, Varma, Varun, Alvarez-Loayza, Patricia, Hurtado Astaiza, Johanna, Bradford, Matt, Fletcher, Christine, Ndoundou-Hockemba, Mireille, Jansen, Patrick A, Kenfack, David, Marshall, Andrew R, Ramesh, B R, Rovero, Francesco, Sankaran, Mahesh
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 25.04.2016; Nature Portfolio
• Subjects: Biodiversity and Ecology; Carbon sequestration; Ecology, environment; Environmental Sciences; Forests; Leerstoelgroep Resource Ecology; Life Sciences; PE&RC; Resource Ecology; Simulation; Trees; Malaysia; United Kingdom > UK; Australia; United States > US; India; carbon storage; Defaunation; tropics; tropical forests
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms11351

Defaunation is causing declines of large-seeded animal-dispersed trees in tropical forests worldwide, but whether and how these declines will affect carbon storage across this biome is unclear. Here we show, using a pan-tropical data set, that simulated declines of large-seeded animal-dispersed trees have contrasting effects on aboveground carbon stocks across Earth's tropical forests. In our simulations, African, American and South Asian forests, which have high proportions of animal-dispersed species, consistently show carbon losses (2-12%), but Southeast Asian and Australian forests, where there are more abiotically dispersed species, show little to no carbon losses or marginal gains (±1%). These patterns result primarily from changes in wood volume, and are underlain by consistent relationships in our empirical data (∼2,100 species), wherein, large-seeded animal-dispersed species are larger as adults than small-seeded animal-dispersed species, but are smaller than abiotically dispersed species. Thus, floristic differences and distinct dispersal mode-seed size-adult size combinations can drive contrasting regional responses to defaunation.