How do biodiversity patterns of river animals emerge from the distributions of common and rare species?

We studied the patterns of commonness and rarity for one vertebrate (fish) and four fresh- water insect taxa (Ephemeroptera, Plecoptera, Trichoptera and Coleoptera) in southwestern France (57,000 km2), and we analysed the relationships between the location of sites and the contribution of commonness...

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Detalles Bibliográficos
Autores: Cucherousset, Julien, Santoul, Frédéric, Figuerola, Jordi, Céréghino, Régis
Tipo de recurso: artículo
Fecha de publicación:2008
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/41200
Acceso en línea:http://hdl.handle.net/10261/41200
Access Level:acceso abierto
Palabra clave:Aquatic insects
Biodiversity
Commonness
Fish
Freshwaters
Rarity
Descripción
Sumario:We studied the patterns of commonness and rarity for one vertebrate (fish) and four fresh- water insect taxa (Ephemeroptera, Plecoptera, Trichoptera and Coleoptera) in southwestern France (57,000 km2), and we analysed the relationships between the location of sites and the contribution of commonness and rarity to species richness within a large stream sys- tem. Richness patterns in fish and aquatic insects were related to the location of sites within the stream system. The number of common and rare fish species increased from up- to downstream areas as a result of downstream additions of species. The number of common insect species peaked in the intermediate section of the river continuum, whereas rarity increased with decreasing elevation. In all taxa, common species gave a closer approximation to overall patterns of species richness than did rare ones. The biodiversity patterns of river animals emerged from convergence in the distributions of common and rare species (fish), or mostly from the distribution of common species (insects). However, in fish, Ephemeroptera and Plecoptera, the rarer species became almost equally, or more strongly correlated with overall species richness when increasing information along the common-to-rare and rare-to-common sequences. These patterns suggested that rarer spe- cies show a similar or stronger affinity, on a species-for-species basis, for high richness areas than do the commoner species. These schemes have implications for biodiversity assessments, as studies using common species richness to target important areas for mon- itoring or conservation efforts within stream systems will not necessarily identify areas important for rare species, and vice versa.