Investigation of benthic environment for recovery of ecological function in Lake Taihu.

• Project/Area Number: 24404008
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 海外学術
• Research Field: Environmental technology/Environmental materials
• Research Institution: Tohoku University
• Principal Investigator: NISHIMURA Osamu 東北大学, 工学(系)研究科(研究院), 教授 (80208214)
• Co-Investigator(Kenkyū-buntansha): NOMURA Munehiro 東北大学, 大学院工学研究科, 助教 (70359537) ; FUJIBAYASHI Megumu 東北大学, 大学院工学研究科, 助教 (70552397)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥17,680,000 (Direct Cost: ¥13,600,000、Indirect Cost: ¥4,080,000); Fiscal Year 2014: ¥5,720,000 (Direct Cost: ¥4,400,000、Indirect Cost: ¥1,320,000); Fiscal Year 2013: ¥5,460,000 (Direct Cost: ¥4,200,000、Indirect Cost: ¥1,260,000); Fiscal Year 2012: ¥6,500,000 (Direct Cost: ¥5,000,000、Indirect Cost: ¥1,500,000)
• Keywords: 底質 / 藍藻 / 高等植物 / 有機物起源 / 脂肪酸 / 安定同位体比 / 太湖 / 同位体比 / 食物連鎖 / 流動 / 底質有機炭素 / アオコ / 底質有機炭素含有率 / 閉鎖性水域

Outline of Final Research Achievements

The origin of sedimentary organic carbon and assimilated food source of dominant benthic animals were investigated with fatty acid biomarker and stable carbon isotope in hyper-eutrophic shallow lake, Lake Taihu in China. While suspended matter in Lake Taihu contained much more cyanobacteria derived fatty acid biomarker than higher plants, higher-plant-derived fatty acid biomarker was dominant in sediments from whole of the lake in summer and winter. Fatty acid analysis revealed that dominant benthic animals mainly assimilated cyanobacteria not higher plants.The consumption of cyanobacteria by benthic animals may one of the possible explanation for accumulation of higher-plant-derived organic carbon in sediments from Taihu.

Research Products

• [Journal Article] Predominance of terrestrial organic matter in sediments from a cyanobacteria-blooming hypereutrophic lake (2015)
  • Author(s): Xiaoguang Xu, Wei Li, Megumu FUJIBAYASHI, Munehiro NOMURA, Osamu NISHIMURA, Xianning Li
  • Journal Title: Ecological Indicators Volume: 50 Pages: 35-43
  • DOI: 10.1016/j.ecolind.2014.10.020
  • Peer Reviewed
• [Journal Article] Feedback of Threshold via estimating sources and composition of sedimentary organic matter across trophic gradients in freshwater lakes (2014)
  • Author(s): Xiaoguang Xu, Wei Li, Megumu Fujibayashi, Menehiro Nomura, Takashi Sakamaki, Osamu Nishimura, Xianning Li
  • Journal Title: Science of the Total Environment Volume: 500-501 Pages: 373-382
  • DOI: 10.1016/j.scitotenv.2014.08.113
  • Peer Reviewed
• [Presentation] Cyanobacteria as a food source for benthic animals in a hyper-eutrophic lake (Lake Taihu, China) (2014)
  • Author(s): Megumu FUJIBAYASHI, Xiaoguang XU, Wei LI, Munehiro NOMURA, Xianning LI, Yoshio AIKAWA, Osamu NISHIMURA
  • Organizer: 8th Shallow Lakes Conference
  • Place of Presentation: Antalya
  • Year and Date: 2014-10-14
• [Presentation] Investigating the sources of sedimentary organic matter in hypereutrophie Lake Taihu (China) by using stable isotope ratio and fatty acid biomarkers. (2013)
  • Author(s): Xu Xiaoguang
  • Organizer: 水環境学会
  • Place of Presentation: 大阪
  • Year and Date: 2013-03-13
• [Presentation] 中国太湖における脂肪酸-炭素安定同位体比を用いた底生生態系の食物連鎖 (2013)
  • Author(s): 藤林恵
  • Organizer: 生態学会
  • Place of Presentation: 静岡
  • Year and Date: 2013-03-07
• [Presentation] 異なる生産者構造を有する富栄養湖湖（太湖、伊豆沼）における底質有機炭素の起源
  • Author(s): 藤林恵、野村宗弘、許暁光、李先寧、相川良雄、西村修
  • Organizer: 日本陸水学会
  • Place of Presentation: 滋賀