Since in most cases essential dissolyed plant nutrients are carried by river freshwater runoff into the sea, estuarine coastal regions are a favourable marine environment for special organic species to recuperate and multiply.

• 由于来自江河的淡水在多数情况下携带大量的营养盐入海，河口海区成为适合于特殊门类的有机物生长的有利海洋环境。