Proposal of a new water environment index connecting the land and coastal areas in consideration of the global water environment

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K06579
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Hydraulic engineering
• Research Institution: Kagawa University
• Principal Investigator: Ishizuka Masahide 香川大学, 創造工学部, 教授 (50324992)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 水ストレス / 水環境リスク / 河川水質 / マイクロプラスチック / 流出解析 / 水ストレス環境インデックス

Outline of Final Research Achievements

By calculating the degree of water stress for each city, the result was obtained that the degree of water stress increased about 2 to 5 times compared to the result calculated for each country.
In Japan, the quality of river water was better than that of rivers in the world, and the degree of water stress did not change significantly even when the water environment was taken into consideration. However, in rivers around the world where water quality has deteriorated, the values of fecal coliforms and heavy metals greatly exceed the water quality standard values. By using the water stress environmental index that considers the water environment, the result was obtained that the degree of water stress became higher than the conventional water stress index calculated only by the amount of water.

Free Research Field

土木工学

Academic Significance and Societal Importance of the Research Achievements

人が実際に利用可能な水資源をより正確に評価するために、河川を通して都市に集水する水ストレスを新たに評価した。さらに、この指標に水環境の要素を加え、新たな水ストレス環境インデックスを提案した。近年あるいは将来的な世界人口増加と異常気象による降水量の時間的・空間的変化に対して、本研究で得た知見は社会的意義が高い。また、水の動態については、複数の河川流出解析や、人工衛星の雨量補正、逆解析、機械学習を行い、様々なパラメタリゼーションを実施した。河川流量の予測が今後実用化されれば、社会的意義は高い。また、新たな水環境指標として明らかにした河川のマイクロプラスチックの特徴は、広く環境問題への啓蒙となる。