Author(s): M. Noguchi; W. Nishida; S. Nomura; Y. Fuchigami
Linked Author(s): Masato Noguchi
Keywords: Non-point pollutants; Total Nitrogen; Detachment Coefficient; Mathematical Simulation
Abstract: In Nagasaki, a big project called the construction of sea-dyke and reclamation project is now going on, so it becomes very important to carry out the watershed management. In order to prevent the eutrophication of water, pollutants such as organic matters, nutrients and so on should be reduced to runoff into the receiving water without treatment. In this paper, detachment rates of pollutants from the non-point pollutant source were first discussed related to the condition of watershed and a series of rainfall. Therefore, necessary data for computation has been prepared using GIS data, and mathematical simulation was carried out to estimate the pollutant runoff rates from non-point pollutant sources. Here, Total Nitrogen (T-N) has been considered as pollutant. As usually understood, pollutants are runoff under not only the wet weather condition but also the dry weather one. Then, after proving appropriateness of detachment coefficient, total amount of T-N from the watershed will be evaluated under both conditions. For this purpose, predictive model of pollutants from non-point sources has been applied to the watershed of regulation pond at Isahaya, Japan. Using the identified value of detachment coefficient, pollutant runoff rates can be predicted with high accuracy.
Year: 2003