Tam Giang - Cau Hai lagoon ecosystem in Thua Thien Hue province is rated as one of the unique ecosystems in the Central coastal. So far, people have found some 400 species. including 250 species of phytoplankton. 54 species of bottom algae. 43 species of algae, 18 species of aquatic plants, 31 species of terrestrial vegetation. The extreme weather events such as big floods, typhoons and waves that cause to freshening salinization of lagoon water. These processes will create extreme conditions. unfavorable habitat for ecosystem creature and processes in lagoon
change ecosystem structure affect on gene resources and biodiversity.