1,Navigation buoys are used as markers
(references) on the vast sea (lake) surface, used to navigate or mark navigation channels and submerged shoals, and mark fishing nets and detection equipment in the water. They are usually anchored to prevent the water from displacing them.
2, The color of the channel buoy must be bright, so that it can be clearly seen in the sea. It is a beautiful landscape on the sea. And in the rough seas, channel buoys have high requirements for collision avoidance.