春日山内小河川における硝酸イオンの流出特性

概要

論文の詳細を見る
Since the nitrogen saturation of soil by acid deposition is an important problem, the biogeochemically concern with water quality formation and material balance by interflow and groundwater runoff has been growing for the recent year. In order to clarify the runoff characteristic of NO3－ and water quality formation at the river in the forest catchment, we carried out the continuous field observation of acid rain, water quality and river discharge. As the results, since NO3- concentration becomes high value with the increase in discharge, it is thought that the hydrological conditions greatly affected the outflow of high NO3- concentration. Moreover, in order to clarify in detail about nitrogen saturation, we analyzed the relation between a NO3-/Cl- ratio and SO42- and NH4＋ using the method of Yoh (2004). The relation between NO3-/Cl- ratio and SO42-, NH4＋ concentration in the river water was increasing and decreasing, respectively. Therefore, it turned out that the denitrification occurs and NO3- concentration decreases in the outflow process to a river.
2007-10-31