On this picture you can see the marine ecosystem loss with on the left the key ecosystem services and on the right the major loss mechanisms. On the right you have dredging and boating effects. Coastal salinity chenges beacause of altered water flow for irrigation. THE POLLUTION DISCHARGED INTO THE SEA BY DIVERSE HUMAN ACTIVITIES CAUSES EUTROPHICATION WHICH REDUCES THE LIGHT AND THE OXYGEN IN THE WATER. ALL THOSE ASPECTS PLAY AN IMPORTANT AND CRITICAL ROLE  IN DAMAGING MARINE ECOSYSTEMS.