A Study on the Change of Landuse of Area around Tega Marsh due to Urbanization and Waterfront Open Spaces

Due to urbanization waterpollution of inland hydrosphere, especially lakes and marshs has become one of the most serious ploblems in recent years. The object area of this study is Tega marsh in Chiba prefecture. It was investigated the changes in landuse due to urbanization, and the relationship between the ratio of greenary and waterquality. Moreover, this study was intended to sum up the effects of natural purgation capacity with waterfront green space due to the treatment system of household wastewater disposition. According to the correlation analysis, it was made clear that the relation of population density and the rate of urbanized area with BOD or COD was very tight. The rate of urbanized area which satisfy the hydroenvironmental criterion by BOD should be 25 %. Question paper analysis shows that the inhabitants of high urbanized area are highly interested in the problem of waterpollution and they desire the stablishment of waterquality purgation planning. Finally, authors proposed that the setting of green area with waterfront plants as one of the successive method has considerable effect in purgation of waterquality.