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Exotic species enhance response diversity to land-use change but modify functional composition.

ABSTRACT: Two main mechanisms may buffer ecosystem functions despite biodiversity loss. First, multiple species could share similar ecological roles, thus providing functional redundancy. Second, species may respond differently to environmental change (response diversity). However, ecosystem function would be best protected when functionally redundant species also show response diversity. This linkage has not been studied directly, so we investigated whether native and exotic pollinator species with similar traits (functional redundancy) differed in abundance (response diversity) across an agricultural intensification gradient. Exotic pollinator species contributed most positive responses, which partially stabilized overall abundance of the pollinator community. However, although some functionally redundant species exhibited response diversity, this was not consistent across functional groups and aggregate abundances within each functional group were rarely stabilized. This shows functional redundancy and response diversity do not always operate in concert. Hence, despite exotic species becoming increasingly dominant in human-modified systems, they cannot replace the functional composition of native species.

SUBMITTER: Stavert JR

PROVIDER: S-EPMC5563801 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Exotic species enhance response diversity to land-use change but modify functional composition.

Stavert Jamie R JR Pattemore David E DE Gaskett Anne C AC Beggs Jacqueline R JR Bartomeus Ignasi I

Proceedings. Biological sciences 20170801 1860

Two main mechanisms may buffer ecosystem functions despite biodiversity loss. First, multiple species could share similar ecological roles, thus providing functional redundancy. Second, species may respond differently to environmental change (response diversity). However, ecosystem function would be best protected when functionally redundant species also show response diversity. This linkage has not been studied directly, so we investigated whether native and exotic pollinator species with simil ...[more]

PMID: 28794218

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Exotic species enhance response diversity to land-use change but modify functional composition.

Publications

Exotic species enhance response diversity to land-use change but modify functional composition.

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