This work was supported by FCT (Fundação para a Ciência e Tecnologia) through a project (MERCOAST) – PTDC/MAR/10916/ 2008 and by POPH and QREN – Promotion of Scientific Job funded by European Social Fund and National funds of MEC. SC Marques is a Postdoctoral Fellow of the FCT (SFRH/BPD/65541/2009).The authors are indebted to all the colleagues that assisted in the field and lab work.