富山湾周辺河川水の水文化学特性と湾への窒素負荷量の予察

概要

論文の詳細を見る
To understand hydro-chemical characteristics of river water and NO3--N load toward Toyama bay through the base flow. The hydrological field survey and analysis of inorganic ion chemistry, stable isotopic ratios of hydrogen and oxygen, and tritium activity in water samples were conducted for 25 rivers around Toyama bay.The isotopic ratio of river water in Toyama prefecture shows different content in comparison with that of Ishikawa prefecture, and water chemistry of small catchment rivers in western part of Toyama prefecture and Noto peninsula, except Kumabuchi and Sakiyama rivers, shows Na+-HCO3- type due to wind-borne chloride. As for the NO3--N load toward Toyama bay, the contribution of rivers with large catchment and the flow through the residential area is relatively large in both prefectures. The results suggested that the isotopic and geochemical characteristics of river water were related to the site of catchment, topographic feature, local geology, and major land use in the catchment area. The estimated annual total NO3--N load toward the bay through the base flow was about 4,200 tons.
日本水文科学会の論文