A regime shift in intertidal assemblages triggered by loss of algal canopies: A multidecadal survey

Canopy-forming macroalgae recently experienced a worldwide decline. This is relevant, because canopies sustain complex food webs in temperate coasts. We assessed the die-back of the canopy-forming alga Fucus serratus in N Spain, at its warm distributional range boundary, and its effects on associate...

Descripción completa

Detalles Bibliográficos
Autores: Álvarez-Losada, Óscar, Arrontes, Julio, Martínez, Brezo, Fernández, Consolación, Viejo, Rosa M.
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universidad Rey Juan Carlos
Repositorio:BURJC-Digital. Repositorio Institucional de la Universidad Rey Juan Carlos
OAI Identifier:oai:burjcdigital.urjc.es:10115/41047
Acceso en línea:https://hdl.handle.net/10115/41047
Access Level:acceso embargado
Palabra clave:Marine ecology
Coastal zone
Canopy-forming algae
Fucus serratus
Climate change
Species distributions
Turf-forming algae
Community composition
Regime shifts
Descripción
Sumario:Canopy-forming macroalgae recently experienced a worldwide decline. This is relevant, because canopies sustain complex food webs in temperate coasts. We assessed the die-back of the canopy-forming alga Fucus serratus in N Spain, at its warm distributional range boundary, and its effects on associated assemblages. We combined long-term descriptive surveys with canopy-removal experiments. Results showed that rapid shifts to turf-forming communities were mostly the direct consequence of the canopy loss, rather than a concurrent process directly triggered by climate change. The switch alters the whole food web, as the prominent role of F.serratus and other cold-temperate intertidal fucoids is not being replaced by functionally equivalent species. Canopy loss caused a rapid biotic homogenization at regional scale which is spreading towards the west, from the edge to the central part of the former distributional range of F.serratus in N Spain. The most obvious effect is the ecological and functional impoverishment of the coastal system.