The biological content of ballast water in China: A review

The introduction of species through the release of ballast water has become a major threats to marine biodiversity and ecosystem function worldwide. China is one of the top trading countries, yet little is known about exotic species in the ballast water of ships coming to its ports. Here, we review the biological surveys of ballast water from major Chinese ports. These surveys reveal that 40 species of non-indigenous phytoplankton that, belong to 25 genera and five phyla, have been observed in ballast water. The dominant species are diatoms and dinoflagellates. There were 17 red-tide causing species observed, five of which are noxious algae. Seventeen species of non-indigenous zooplankton have been reported, most of them (11) copepods. There were also 22 species of pathogenic bacteria recorded, including Vibrio alginolyticus, V. carchariae, V. parahaemolyticus, and V. vulnificus. These studies show that species introduction through ballast water potentially a serious threat to the ecology and human health in China. More research, including collaboration with the international community, is urgently needed to address this problem.