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(20-11) Development of GIS-based simulation method for water quality of Japanese rivers. Murasawa, Kaori*,1, Suzuki, Noriyuki1, Sakurai, Takeo1, Matsuhashi, Keisuke1, Tanabe, Kiyoshi1, Moriguchi, Yuichi1, Nakasugi, Osami1, Morita, Masatoshi1, 1 National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki Pref., Japan ABSTRACT- It has been a popular manner to use environmental models for assessment of hazardous compounds. They are often applied to site-specific simulations in local/regional areas or hypothetical simulations in common environments. Applying a model simulation for assessment in non-hypothetical wide area, such as a whole country, researchers are obliged to put a great effort on preparing environmental parameters for the model. This causes difficulty in comparing regions and also in utilizing nationwide emission data, such as data from PRTR (Pollutant Release and Transfer Resister) in Japan. To contribute a nationwide assessment of hazardous compounds in Japanese river water, we have been building a GIS (Geographical Information System)-based simulation system of water quality in Japan. Based on a numeric map data provided by the Geographical Survey Institute in Japan, river catchment polygons and lines of river courses, each of which has several km to several tenth km size, were built into a linked database. River connections and flows were defined and arranged into the database. Thus the river database composed of ten sorted data tables was developed. Three river models of different levels were built and adopted on each catchment. They are a plug flow dilution model, a plug flow dilution model with decay factors, and a compartment model. They have a target of local to regional assessment of the aquatic environment. They work with the river database, and the whole simulation system was designed to have choices of Japanese rivers and the river models. Key words: river model, GIS, database, hazardous compounds |
