@article{oai:yamanashi.repo.nii.ac.jp:00001706, author = {坂本, 康 and 中村, 文雄 and 風間, ふたば}, journal = {山梨大學工學部研究報告, Reports of the Faculty of Engineering, Yamanashi University}, month = {Dec}, note = {Nitrate concentrations in groundwater-derived potable supplies were examined for their time variation. Sample waters were collected from two faucets of municipal water supplies and a neighboring river to determine their seasonal quality changes and daily quality changes following rainfall events. The results showed that (1) the nitrate concentrations were lower for a period from October to December during which organic and ammonia nitrogen of agricultural supplies had not yet been converted to nitrate, (2) the nitrate concentrations increased during several days after rainfall events, (3) time between rainfall events and concentration peaks became shorter when the soil became humid because of antecedent rainfalls, and (4) the relationships between NO_3^- and SO_4^<2-> concentrations at peaks after rainfall events could be different from those on fine days.}, pages = {120--125}, title = {地下水を資源とする水道水の硝酸イオン濃度の時間的変動}, volume = {42}, year = {1991} }