Why is the East China Sea an area of high marine-life productivity?

The East China Sea is a region of high marine-life productivity primarily due to the availability of nutrients and the influence of ocean currents.21

Biological productivity in the sea is largely driven by the presence of phytoplankton, which require an adequate supply of nutrients to perform photosynthesis and transform solar energy into chemical energy. In the East China Sea, these essential nutrients are supplied in part by the massive volume of sediment and material carried by the Yangtze River and other rivers, which deposit vast amounts of alluvium into the shallow continental shelf areas.123

Additionally, the sea's circulation is influenced by the Kuroshio (Japan Current), a warm, north-flowing current that helps distribute water and nutrients throughout the region. The combination of these nutrient-rich river discharges and the dynamic movement of currents creates an environment that supports a diverse range of marine life, including tuna, mackerel, shrimps, and seaweeds.2