Dataset Information

Divergent biodiversity change within ecosystems.

ABSTRACT: The Earth's ecosystems are under unprecedented pressure, yet the nature of contemporary biodiversity change is not well understood. Growing evidence that community size is regulated highlights the need for improved understanding of community dynamics. As stability in community size could be underpinned by marked temporal turnover, a key question is the extent to which changes in both biodiversity dimensions (temporal ?- and temporal ?-diversity) covary within and among the assemblages that comprise natural communities. Here, we draw on a multiassemblage dataset (encompassing vertebrates, invertebrates, and unicellular plants) from a tropical freshwater ecosystem and employ a cyclic shift randomization to assess whether any directional change in temporal ?-diversity and temporal ?-diversity exceeds baseline levels. In the majority of cases, ?-diversity remains stable over the 5-y time frame of our analysis, with little evidence for systematic change at the community level. In contrast, temporal ?-diversity changes are more prevalent, and the two diversity dimensions are decoupled at both the within- and among-assemblage level. Consequently, a pressing research challenge is to establish how turnover supports regulation and when elevated temporal ?-diversity jeopardizes community integrity.

SUBMITTER: Magurran AE

PROVIDER: S-EPMC5828582 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Divergent biodiversity change within ecosystems.

Magurran Anne E AE Deacon Amy E AE Moyes Faye F Shimadzu Hideyasu H Dornelas Maria M Phillip Dawn A T DAT Ramnarine Indar W IW

Proceedings of the National Academy of Sciences of the United States of America 20180212 8

The Earth's ecosystems are under unprecedented pressure, yet the nature of contemporary biodiversity change is not well understood. Growing evidence that community size is regulated highlights the need for improved understanding of community dynamics. As stability in community size could be underpinned by marked temporal turnover, a key question is the extent to which changes in both biodiversity dimensions (temporal α- and temporal β-diversity) covary within and among the assemblages that compr ...[more]

PMID: 29440416

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Dataset Information

Divergent biodiversity change within ecosystems.

Publications

Divergent biodiversity change within ecosystems.

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