Abstract
Dried leaf fragments of the Mediterranean seagrass Posidonia oceanica were used as tracer particles to test if seagrass leaf canopies reduce particle resuspension. Half Petri dishes containing a known mass of tracer particles were deployed for 24 h, five times during the summer period inside a 15-m deep P. oceanica meadow and on an adjacent sandy bottom devoid of vegetation. The loss of tracer particles was consistently high (> 62.9% of initial particle mass) at sand stations, while both high (> 79.2% of initial particle mass) and low (< 47.7% of initial particle mass) losses were recorded at P. oceanica stations. The loss of tracer particles was lower (P < 0.01) within the P. oceanica meadow than over barren sand, which supports the hypothesis that seagrass leaf canopies are able to reduce particle resuspension. | This research was funded by the ELOISE programme of the European Commission (project ‘Physical forcing and biogeochemical fluxes in shallow coastal ecosystems’, contract MAS3-CT96-0053). J. Terrados was supported by the Spanish Ministry of Education and Culture. We thank E. Gacia for help during field work, and T. Granata and E. Gacia for comments on a former version of the manuscript.