Influence of Regional Warming Trend on Water Quality Change in Lake as Agricultural Water Resources

• Project/Area Number: 25450364
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Rural environmental engineering/Planning
• Research Institution: Kagoshima University
• Principal Investigator: MOMII KAZURO 鹿児島大学, 農水産獣医学域農学系, 教授 (40136536)
• Co-Investigator(Kenkyū-buntansha): ITO Yuji 鹿児島大学, 農水産獣医学域農学系, 准教授 (60526911)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000); Fiscal Year 2015: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2014: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2013: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
• Keywords: 湖水循環 / ポテンシャルエネルギー / 乱れエネルギー / 数値解析 / 植物プランクトン / 栄養塩濃度 / 溶存酸素 / 熱環境 / 全循環 / 湖水温 / クロロフィル / 数値計算 / 農業用水資源 / 水温成層 / 部分循環 / 温暖化 / 水温 / 湖水 / 水質

Outline of Final Research Achievements

Based on the field observation and numerical simulation, this study focuses on the influence of the regional warming trend on the water quality and circulation of the lake as valuable water resources in the study site. Concerning the lake water circulation, the numerical results show that the potential energy of the lake water becomes smaller than the wind-induced turbulent energy for the vertical mixing in February of 1986, 2011 and 2012 during 1986-2013. The simulation study reveals that the decrease in the potential energy is caused by the temporal hiatus in the air temperature increase since 2000 in comparison with 1977-1999. The results on the water quality suggest that the long-term fluctuations of the lake thermal environment due to the regional climate change favor eutrophication and chlorophyll maxima in the deep layer, but that the drastic changes in water quality like red tide cannot occur due to very low concentration of phosphorous in Lake Ikeda.

Research Products

• [Journal Article] Impacts of regional warming on long-term hypolimnetic anoxia and dissolved oxygen concentration in a deep lake (2015)
  • Author(s): Ito, Y. and K. Momii
  • Journal Title: Hydrological Processes Volume: 未定 Issue: 9 Pages: 2232-2242
  • DOI: 10.1002/hyp.10362
  • Peer Reviewed / Open Access
• [Presentation] 湖の熱環境に影響を及ぼす地域的環境要因 (2015)
  • Author(s): 村田龍星，伊藤祐二，籾井和朗
  • Organizer: 農業農村工学会九州・沖縄支部大会
  • Place of Presentation: ANAクラウンプラザホテル那覇ハーバービュー（沖縄県，那覇市）
  • Year and Date: 2015-10-29
• [Presentation] Thermal responses to regional changes in climate and water clarity in Lake Ikeda, Japan (2015)
  • Author(s): Ito, Y., Ando, J. and Momii, K.
  • Organizer: HydroEco2015 (5th international multidisciplinary conference on hydrology and ecology)
  • Place of Presentation: The University of Natural Resources and Life Science (Vienna, Austria)
  • Year and Date: 2015-04-15
  • Int'l Joint Research
• [Presentation] 池田湖の温暖化と熱特性の変化 (2014)
  • Author(s): 伊藤祐二・織田翔平・籾井和朗
  • Organizer: 水文・水資源学会2014年度研究発表会
  • Place of Presentation: 宮崎グリーンスフィア壱番館（宮崎県，宮崎市）
  • Year and Date: 2014-09-25
• [Presentation] 池田湖における長期モニタリングと湖水環境の変化
  • Author(s): 伊藤祐二・籾井和朗
  • Organizer: 日本陸水学会第78回大会（公開シンポジウム）
  • Place of Presentation: 龍谷大学瀬田キャンパス（大津）
• [Presentation] 池田湖の全循環発生と溶存酸素の季節変化
  • Author(s): 伊藤祐二・籾井和朗・大久保道徳
  • Organizer: 農業農村工学会九州沖縄支部大会
  • Place of Presentation: 宮崎観光ホテル（宮崎）
• [Presentation] 農業用水資源としての地下水および湖水における物質動態に関する研究
  • Author(s): 籾井和朗
  • Organizer: 農業農村工学会応用水理研究部会
  • Place of Presentation: 京都大学農学部総合館（京都）
  • Invited