Construction of a symbiotic system of sea urchins and seaweeds by creating seaweed beds using detachable substrates

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K06209
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 40030:Aquatic bioproduction science-related
• Research Institution: Kagawa University
• Principal Investigator: Suenaga Yoshihiro 香川大学, 創造工学部, 教授 (00284349)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ウニ / 藻場 / 浮上式基質 / AI / 投入方法

Outline of Final Research Achievements

Coastal area of Tohoku region, which is close to the Shiome where the Oyashio and the Kuroshio collide is one of the highest fisheries catches in Japan. However, due to the damage caused by fishery ground subsidence caused by the Great East Japan Earthquake 2011.Isoyake phenomenon continues, and the catch amount tends to decline. Furthermore, the aging and reduction of fishermen triggers the decrease of catches, leading to serious problems in fisheries productivity. In this study, we develop a technology that enables symbiosis of Sea Urchin and Kombu, and to gather Sea Urchin to create seaweed bed in a cost-effective method prescribed by the MAFF.As a result, we gained a foundational knowledge in creating a sea area to construct a symbiotic technology of Sea Urchin and Kombu, that is also safe for older fishermen to use. Also, using AI we have confirmed a method to discriminate between the concentration of Sea Urchin and efficiently installation for enhancement substrate of Kombu.

Free Research Field

水圏環境工学，水産工学

Academic Significance and Societal Importance of the Research Achievements

震災海域における藻場造成，磯根資源生産力の回復・向上を目的として，当該海域に様々な技術が提供されてきたが，ウニの生息密度の高さと食圧等により，効果の発現に乏しかった．その中で，昆布を対象とした藻場造成手法の開発に取り組み，海藻の着生と成長が認められた手法を見出し，高密度にウニが生息する場でも昆布場を造成でき，ウニと昆布の共生が可能となる知見を得た．
本研究では，ウニによる初期食害抑制技術として浮上式基質投入法の開発と漁場規模に応じた費用対効果の算定，ウニと昆布の共生技術の効果を検証した．また，漁業者が効率的な作業を行うために，AIによるウニの生息密度に対する浮上式基質の最適な投入方法も提案した．