Immediate and delayed effects of a mass mortality event on gorgonian population dynamics and benthic community structure in the NW Mediterranean Sea

摘要: In the boreal summer of 1999, many invertebrates hard-bottom communities in NW Mediterranean Sea suffered mass mortality. Our study assessed population temperate octocoral Paramuricea clavata before event and monitored over following 4 yr. Spatial patterns showed decreasing mortality with increasing depth between 0 50 m, as well high local variability. The temporal pattern was characterized by a sharp decrease biomass (58%) shortly after caused combined effect colony death (9% population) an increase extent injury (from 9% to 52% it). After yr monitoring, our results indicated large delayed event. Population density decreased continuously November completion 2003 accu- mulated 48% initial population. This mainly due colonies subjected extensive injury, because recruitment did not offset continued at slow rate, becoming almost constant 2001. Overall, accounted for 70% loss P. bio- mass. fact that stabilization this species observed during last year suggests impact 1999 may be near- ing its end. Nevertheless, given low dynamics role habitat former, indicates relevant disturbance can play on community structuring force coralligenous community.