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

ABSTRACT: 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.

SUBMITTER: Osuri AM

PROVIDER: S-EPMC4848488 | biostudies-other | 2016

REPOSITORIES: biostudies-other

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

Osuri Anand M AM Ratnam Jayashree J Varma Varun V Alvarez-Loayza Patricia P Hurtado Astaiza Johanna J Bradford Matt M Fletcher Christine C Ndoundou-Hockemba Mireille M Jansen Patrick A PA Kenfack David D Marshall Andrew R AR Ramesh B R BR Rovero Francesco F Sankaran Mahesh M

Nature communications 20160425

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 ...[more]

PMID: 27108957

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Dataset Information

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

Publications

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

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