 The waters around Dongyin host large schools of fish, and coral reefs, which makes Dongyin one of the best domestic fishing spots and the most densely populated conservation area for "Larus crassirostris" ().The geological formation of Dongyin is closely related to Mainland China, where the granite bedrock was formed by Yanshan Movement () dated to 100 – 200 million years ago.Thanks to its resistance to weathering, granite bedrock is seen above ground widespread in Dongyin.