Author(s): Masato Noguchi; Yusaku Fuchigami; Masakazu Furue; Kenta Ryu; Nobuki Morio; Kenji Kawaike; Makoto Nishikawa
Linked Author(s): Kenji Kawaike
Keywords: Field observation; Mathematical model; Non-point sources; Total nitrogen; Urban area; Wet weather condition
Abstract: There are lots of closed water bodies as receiving water around us, and it is strongly expected that a sound and sustainable condition could be achieved at present and in the near future. For this purpose, it should be emphasized to carry out the integrated management of river and its watershed (Noguchi et al. 2002, Noguchi 2003). Among all, reduction of pollutant runoff loads from non-point sources has urgently been required, so that we have to know the pollutant runoff mechanism, especially under the wet weather condition. Considering the water bodies, nutrients discharged without any treatment have to be reduced in order to prevent and/or mitigate the damages due to “eutrophication”. In this paper, how to precisely predict the runoff rates of Total-Nitrogen (T-N) under the wet weather condition at urban area has been discussed, carrying out the field observation and the mathematical computation. In order to appropriately predict the runoff rate, mass balance equation of pollutants should be solved at a layer of bed materials as well as in the flows. Comparing both results of field observation and mathematical computation, it has been shown that temporal variation of T-N loads from non-point sources under the wet weather condition can exactly be predicted through the above-mentioned procedure.
Year: 2005