Sewage-induced polychaete reefs in a SW Atlantic shore: Rapid response to small-scale disturbance

The intertidal zone around Mar del Plata's sewage discharge (38°S, 57°W) is characterized by the presence of the non-indigenous spionid polychaete Boccardia proboscidea. This species has been classified as tolerant to moderate and high levels of organic contamination. During early stages of col...

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Detalles Bibliográficos
Autores: Garaffo, Griselda Valeria, Jaubet, Maria Lourdes, Sánchez, María de Los Angeles, Rivero, María S., Vallarino, Eduardo Alberto, Elias, Rodolfo
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/152715
Acceso en línea:http://hdl.handle.net/11336/152715
Access Level:acceso abierto
Palabra clave:INTERTIDAL
POLYCHAETE REEFS
SEWAGE-IMPACTED AREA
SOUTHWEST ATLANTIC
SPIONIDAE
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descripción
Sumario:The intertidal zone around Mar del Plata's sewage discharge (38°S, 57°W) is characterized by the presence of the non-indigenous spionid polychaete Boccardia proboscidea. This species has been classified as tolerant to moderate and high levels of organic contamination. During early stages of colonization this species can reach very high densities without suffering from interspecific competition, building biogenic structures such as reef. The aim of this work was evaluate the recovery time of the reef to a small-scale experimental physical disturbance. Five independent rocks with B. proboscidea reefs on them were selected randomly and a small-scale disturbance was generated by corers (16cm 2). At the beginning of the experiment, six corers were collected in each reef to produce the disturbance. The original density of B. proboscidea in each reef was determined in these corers. The reefs with disturbed corer were sampled on successive days to assess the reef recovery time. The number of larvae, juveniles and adults was quantified. Polychaete reefs had very high densities before the disturbance (mean density: 1,021,250indm -2). Boccardiaproboscidea reefs had a fast recovery rate after small-scale disturbance. Four days after disturbance the density reached about 50% of the original density and after 5days the disturbed reefs could not be differentiated from the undisturbed reef. The initial recolonization of disturbed patches occurs as a result of migration which appears to be driven by larvae and juveniles. These reefs can not be seen as biodiversity hotspots and the presence of the species demonstrates great environmental deterioration.