A Numerical Assessment of Organic Pollution in the River Yoshino and Its Tributaries in Tokushima Prefecture, Using Attached Diatom Assemblages
四国吉野川の有機汚濁に対する付着珪藻群集を指標とした生物学的数量評価

MASAYUKI KOJIMA, TOSHIHARU WATANABE
1997 Japanese Journal of Water Treatment Biology  
In the River Yoshino and its tributaries,30 samples of attached diatom assemblage on the river bed were collected and some physicochemical values of river water in each sampling site were measured in September and October 1996 and February 1997.In this study,the following results were obtained. 1.The DAIpo values ranged from 55 to 91 in this river system,indicating that the degree of water pollution at almost all sites corresponds to a-oligosaprobic in the former saprobic level. 2.From the
more » ... ical water pollution chart for this river using the DAIpo value of each sampling site,the main course of this river was classified into next three course. (1) Clean upper course from site 1 to site 7, DAIpo values over 80. (2) Clean middle course from site 8 to site 17, DAIpo values from 70 to 79. (3) Polluted lower course from site 18 to site 20, DAIpo values bellow 70.
doi:10.2521/jswtb.33.171 fatcat:4ym5mu2x55aspjd7q5w3rg6qjy