Is light environment on a lake bottom affect productivity and biodiversity?

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K00623
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Environmental and ecological symbiosis
• Research Institution: Shiga University
• Principal Investigator: Ishikawa Toshiyuki 滋賀大学, 教育学部, 准教授 (50396313)
• Research Collaborator: Wu Qianqian
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 透明度 / 湖底 / 底生藻類 / 底生動物 / エビ類 / ヨコエビ類 / 外来種

Outline of Final Research Achievements

Relationships between light intensity and mass of periphyton on sediment (epipelon) and between masses of epipelon and of benthic invertebrates were examined in Lake Biwa, where transparency has been improved. There were positive correlation between light intensity and epipelon mass, which suggests improvement of transparency leads increase of epipelon mass. There were positive correlation between masses of epipelon and of some benthic invertebrates (Pleuroceridae), which indicates effect of epipelon differ according to taxon and/or feeding ecology.
Also, knowledge of large benthic crustacean (Decapoda, Amphipoda)in Lake Biwa has been updated, especially, in terms of their distribution, movement and species interactions.

Free Research Field

湖沼生態学

Academic Significance and Societal Importance of the Research Achievements

湖沼における透明度の増加は、浮遊生態系において生物の現存量の低下を示すことが指摘されてきたが、本研究により底生生態系において生物の現存量の増加につながる可能性と、分類ごとに反応が異なることを示すことができた。このことは、湖沼の水質改善の波及効果の議論を深化させうるものである。また、漁獲対象種や漁獲対象種の餌として重要な大型甲殻類の分布や分布の検出方法の開発、外来種の影響について示すことができ、生物多様性の保全に資する知見を集積することができた。