The microcosm of particles within seagrass Posidonia oceanica canopies

Comparison of the amount and nature of suspended matenal within Pos~donia oceanica canopies, in 6 meadows in the Spanish Mediterranean coast differing in extent and depth, with those in the overlying waters showed the canopies to be significantly enriched in particulate organic carbon, nitrogen and...

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Detalles Bibliográficos
Autores: Duarte, Carlos M., Benavent, Esther, Sánchez, M. Carmen
Tipo de recurso: artículo
Fecha de publicación:1999
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/56028
Acceso en línea:http://hdl.handle.net/10261/56028
Access Level:acceso abierto
Palabra clave:Seagrass
Seston
Sedimentation
Detritus
Descripción
Sumario:Comparison of the amount and nature of suspended matenal within Pos~donia oceanica canopies, in 6 meadows in the Spanish Mediterranean coast differing in extent and depth, with those in the overlying waters showed the canopies to be significantly enriched in particulate organic carbon, nitrogen and phosphorus relative to the overlying waters (on average, 87, 34 and 54 % more C, N and P, respectively). Biovolume of detntus (both angiosperm-denved and plankton-denved) was large, par- ticularly within seagrass canopies, where it dominated the seston pool (about 5-fold greater biovolume than that of living particles), compared to a roughly equal biovolume of detntal and llving particles in the parhcle pools in the overlying waters. The dominance of detrital particles was further reflected in the high C/N and C/P ratios of the suspended materials (median atonuc C : N . P ratios = 492: 40.9: 1 and 596:45.1 of the matenals suspended within the canopy and in the overly~ng waters, respectively), which were intermediate between those of living plankton and P oceanica. The relative ennchment of P oceanica canopies by part~cles tended to be greatest when particle loads in the overlying waters were small, suggesting that the effect of seagrasses as traps of particles is enhanced in particle-poor waters The results obtained support the hypothesis that the water within seagrass canopies is enriched by (mostly detrital) part~cles, particularly In particle-poor waters T h ~ s suggests that seagrasses not only contribute a substanhal fraction of the particles themselves, but also act as sinks of particles.