The most suitable time and depth to sample Cymodocea nodosa (Ucria) Ascherson meadows in the shallow coastal area. Experiences from the northern Adriatic Sea

Seagrasses are amongst the most valuable ecosystems on shallow subtidal soft bottoms worldwide (COSTANZA et al., 1997; TUYA et al., 2014). They are considered as ecological engineers (WRIGHT & JONES, 2006), providing food, shelters and nursery areas for a variety of fish and invertebrates (HEMMINGA & DUARTE, 2000; COMO et al., 2008; ESPINO et al., 2015). Moreover, seagrass beds stabilize sediments by trapping fine sediments and particles that are suspended in the water column (CABAÇO et al., 2010), provide protection against coastal erosion (TERRADOS & BORUM, 2004), produce oxygen (PEDUZZI & VUKOVIČ, 1990) and play an important role as global carbon sinks (DUARTE et al., 2010). Therefore, they are recognized as one of the priority habitats in the EU Habitat Directive (HD, 92/43/ EEC). Since coastal ecosystems are subjected to very intense human pressures, affecting light and nutrient resources (HEMMINGA & DUARTE, 2000), as well as causing mechanical damage to the sea bottom by anchoring, dredging and filling, as part of coastal urban development