underwater posidonia oceanica seagrass seen in the mediterranean sea with clear blue water. meadows of this algae are important

absorption algae aquatic balearic bio breathe carbon close closeup coast colors ecosystem environment environmental field fish grassland green growing healthy many marine meadows mediterranean menorca oceanica organic plant plants pollution poseidonia posidonia posidoniaceae rhizomes roots sea seabed seagrass seaweed spain summer sun under underwater water wet