Aerial view of an artificial reef created to protect the coastline of a city

seaweed ocean ocean floor sea bed reef sea sponge underwater scuba scuba diver pacific ocean sea grass ocean rubbish enviroment global warming sea level coral bleaching climate change eco ocean conservation marine biology study pollution fish nature animals vegetation sea vegetables kelp plants marine plant aquarium habitat ecosystems ocean plants marine animals aquatic plants sand mangroves artificial reef beach erosion sand bags underwater construction man made enviromental protection erosion control underwater structure commercial diver coastline city narrow neck