Dataset Information

Rapid decay of tree-community composition in Amazonian forest fragments.

ABSTRACT: Forest fragmentation is considered a greater threat to vertebrates than to tree communities because individual trees are typically long-lived and require only small areas for survival. Here we show that forest fragmentation provokes surprisingly rapid and profound alterations in Amazonian tree-community composition. Results were derived from a 22-year study of exceptionally diverse tree communities in 40 1-ha plots in fragmented and intact forests, which were sampled repeatedly before and after fragment isolation. Within these plots, trajectories of change in abundance were assessed for 267 genera and 1,162 tree species. Abrupt shifts in floristic composition were driven by sharply accelerated tree mortality and recruitment within approximately 100 m of fragment margins, causing rapid species turnover and population declines or local extinctions of many large-seeded, slow-growing, and old-growth taxa; a striking increase in a smaller set of disturbance-adapted and abiotically dispersed species; and significant shifts in tree size distributions. Even among old-growth trees, species composition in fragments is being restructured substantially, with subcanopy species that rely on animal seed-dispersers and have obligate outbreeding being the most strongly disadvantaged. These diverse changes in tree communities are likely to have wide-ranging impacts on forest architecture, canopy-gap dynamics, plant-animal interactions, and forest carbon storage.

SUBMITTER: Laurance WF

PROVIDER: S-EPMC1682011 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature

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Rapid decay of tree-community composition in Amazonian forest fragments.

Laurance William F WF Nascimento Henrique E M HE Laurance Susan G SG Andrade Ana A Ribeiro José E L S JE Giraldo Juan Pablo JP Lovejoy Thomas E TE Condit Richard R Chave Jerome J Harms Kyle E KE D'Angelo Sammya S

Proceedings of the National Academy of Sciences of the United States of America 20061205 50

Forest fragmentation is considered a greater threat to vertebrates than to tree communities because individual trees are typically long-lived and require only small areas for survival. Here we show that forest fragmentation provokes surprisingly rapid and profound alterations in Amazonian tree-community composition. Results were derived from a 22-year study of exceptionally diverse tree communities in 40 1-ha plots in fragmented and intact forests, which were sampled repeatedly before and after ...[more]

PMID: 17148598

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Dataset Information

Rapid decay of tree-community composition in Amazonian forest fragments.

Publications

Rapid decay of tree-community composition in Amazonian forest fragments.

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