Meiofaunal density distribution was studied from 400 m to 1500 m depth inside Blanes submarine canyon (NW Mediterranean), and on the eastern open slope in autumn 2003 and spring 2004.
Our multidisciplinary approach allowed to study the hydrodynamics and sedimentary processes in the Blanes Canyon that characterize it as highly heterogeneous environment. Inside the canyon area, particle fluxes were higher than on the slope area, increased from autumn to spring and mostly consisted of lith-ogenic material. Moreover the canyon's locations experienced more intense bottoms' currents and sediment disturbance, being reflected in a greater variability of meiobenthic densities, both between stations and sampling times than on the open slope. No clear trends (e.g. declining densities) associated with increasing depths were observed.
Contrary in the open slope, current velocities were relatively lower compared with the canyon area and showed lower temporal variability. At the same time, the nutritional quality of the particle fluxes at deeper grounds were higher, probably allowing the meiofaunal densities not to change over time.
In conclusion, the meiobenthos in our system apparently showed a higher temporal variability, inside the canyon area, strongly affected by particle fluxes or erosive and sediment-mixing processes linked to current modifications induced by the canyon topography. |
