Present and Future of the Yellow Sea Ecosystem with the emphasis on the YS Cold Water Mass

Abstract

The Yellow Sea, as one of 64 Large Marine Ecosystems (LMEs) over the world, is known for remarkably high productivity. The Yellow Sea Bottom Cold Water Mass (YSBCWM) is a representative physical property (<10℃, ca. 32psu) which occupies most (~70%) of the Yellow Sea’s water mass in summer and plays a role of shelter for key zooplankton species (Calanus sinicus and Euphausia pacifica) in summer. These two species are very imperative food items to the commercial fishes such as sardine and anchovy, thus ecological study on the zooplankton can give us important information to implement ecosystem-based management on the Yellow Sea ecosystem in relation to the climate variability and anthropogenic impacts. For implementing the ecosystem-based management, structuring of representative marine food-web is prerequisite to assess the response of ecosystem to the natural and anthropogenic variability. If the food-web structure of YSLME is tentatively formed, the marine food-web structure of YSBCWM will be studied in response to the possible affecting environmental changes such as rapid warming of surface water by climate change, variation of strength of Kuroshio Current, and appearance of episodic events (super-typhoon, jet stream, etc). As a good example of food-web response by anthropogenic impact, the regime shift of classical planktonic food-web of Yellow Sea in 1989 was related with drastic increase of anthropogenic activities, particularly fishing, urbanizing, and aqua- and agriculture before and after 1990’s (www.yslme.org). Through this study, the marine food continuum is under structure considering spring and summer based on YSBCWM and eventually the response of the structure and function of food-web in the Yellow Sea to abovementioned environmental changes will be studied.