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Competition drives clumpy species coexistence in estuarine phytoplankton.

ABSTRACT: Understanding the mechanisms that maintain biodiversity is a fundamental problem in ecology. Competition is thought to reduce diversity, but hundreds of microbial aquatic primary producers species coexist and compete for a few essential resources (e.g., nutrients and light). Here, we show that resource competition is a plausible mechanism for explaining clumpy distribution on individual species volume (a proxy for the niche) of estuarine phytoplankton communities ranging from North America to South America and Europe, supporting the Emergent Neutrality hypothesis. Furthermore, such a clumpy distribution was also observed throughout the Holocene in diatoms from a sediment core. A Lotka-Volterra competition model predicted position in the niche axis and functional affiliation of dominant species within and among clumps. Results support the coexistence of functionally equivalent species in ecosystems and indicate that resource competition may be a key process to shape the size structure of estuarine phytoplankton, which in turn drives ecosystem functioning.

SUBMITTER: Segura AM

PROVIDER: S-EPMC3539148 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Competition drives clumpy species coexistence in estuarine phytoplankton.

Segura A M AM Kruk C C Calliari D D García-Rodriguez F F Conde D D Widdicombe C E CE Fort H H

Scientific reports 20130108

Understanding the mechanisms that maintain biodiversity is a fundamental problem in ecology. Competition is thought to reduce diversity, but hundreds of microbial aquatic primary producers species coexist and compete for a few essential resources (e.g., nutrients and light). Here, we show that resource competition is a plausible mechanism for explaining clumpy distribution on individual species volume (a proxy for the niche) of estuarine phytoplankton communities ranging from North America to So ...[more]

PMID: 23301158

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Dataset Information

Competition drives clumpy species coexistence in estuarine phytoplankton.

Publications

Competition drives clumpy species coexistence in estuarine phytoplankton.

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