Study for mechanisms of responses of coastal marine ecosystem and biogeochemical cycle to environmental changes

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I studied mechanisms of responses of marine ecosystem and biogeochemical cycle to environmental changes focusing on the Bungo Chanel in the Seto Inland Sea, where is a typical coastal region fronting to the open ocean. I found the mechanisms of the ecosystem responses to the following abrupt environmental changes;1. The intrusion of oceanic subsurface water to coastal bottom layer is called "Sokoirishio". Sokoirishio supplies much amount of nutrient from the open ocean to the coast, and causes the abrupt change of ecosystem to the productive ecosystem dominated by diatom.2. The super heavy rain in the summer of 2012 supplied huge amount of fresh water to the ocean, and the low salinity and low density water broadly covered the surface layer of coastal region. This water blocked the intrusion of oceanic surface water to coastal surface layer, which is called "Kyucho" and can clean the polluted coastal water. The blocking of Kyucho might be lead to the large scale harmful algae bloom.