Mechanisms controlling the biological productivity of the open ocean

2016 Fiscal Year Final Research Report

• Project Area: New Ocean Paradigm on Its Biogeochemistry, Ecosystem and Sustainable Use
• Project/Area Number: 24121006
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Complex systems
• Research Institution: Nagasaki University
• Principal Investigator: TAKEDA Shigenobu 長崎大学, 水産・環境科学総合研究科(水産), 教授 (20334328)
• Co-Investigator(Kenkyū-buntansha): 佐藤 光秀 東京大学, 農学生命科学研究科, 助教 (60466810)
• Project Period (FY): 2012-06-28 – 2017-03-31
• Keywords: 海洋生態 / 物質循環 / 植物プランクトン / 栄養塩 / 微量金属 / 太平洋

Outline of Final Research Achievements

In various ocean provinces in the Pacific, this study worked on elucidation of the control mechanism of the primary production which drove material cycling in the ocean. The macro- and micro-nutrients limitation status of microbes and phytoplankton, especially phosphorus and iron limitation, was clarified in the Pacific. It was suggested that an increase in sea surface temperature will lead to a prevalence of the larger eukaryotic phytoplankton in the subtropical waters, probably due to the enhancement of phagotrophic mixotrophy under the warmer, more oligotrophic environments. Based on the extracted major environmental factors controlling the primary productivity in the subarctic and subtropical North Pacific, the equatorial Pacific, and the subtropical South Pacific, it was recognized that a micro-nutrient iron plays various roles in each ocean provinces, and the phosphorus cycle is a key for description of the biological production processes in the oligotrophic subtropical waters.

Free Research Field

海洋生物地球化学