Estimation method of groundwater origin in a landslide block based on snowmelt effect and regional groundwater flow system

2014 Fiscal Year Final Research Report

• Project/Area Number: 25892030
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Rural environmental engineering/Planning
• Research Institution: National Agriculture and Food Research Organization
• Principal Investigator: TSUCHIHARA Takeo 独立行政法人農業・食品産業技術総合研究機構, 農村工学研究所・資源循環工学研究領域, 主任研究員 (30399365)
• Project Period (FY): 2013-08-30 – 2015-03-31
• Keywords: 地すべり / 地下水涵養 / 融雪 / 同位体

Outline of Final Research Achievements

The stable isotope compositions of deuterium and oxygen-18 of groundwater, and age-dating using an inactive gas and radioisotope indicate the multi-layered groundwater flow system in the landslide block, and the difference of recharged areas including the outside of the landslide brock. The clear and similar altitude effect of the stable isotope ratios of stream water in the regional watershed was observed in 3 seasons except snowmelt season. The stable isotope ratio of spring run-off in the snowmelt season is different from in other seasons, and therefore the altitude effect except in the snowmelt season can be effective for estimating groundwater recharged areas. It is thus deduced that when used together, these environmental tracers applied in this study can help to know the groundwater flow systems and the recharged area in the landslide block in snowy region.

Free Research Field

水資源工学