Miyajimanuma, Tegatanuma (Bibai City), Misuminuma (Iwamisawa City), Urausunuma, Shinnuma (Urausu Town), Chashinainuma (Naie Town), Fukurochinuma (Shintotsukawa Town, Sunagawa City) are mainly crescentic lakes located at the middle Ishikarigawa river basin. Surrounding areas are agricultural lands, mainly for rice crop, and lowland swamp vegetation such as Alnus japonica, Salix and Phragmites australis are found around lakes and marshes. At Tsukigase swamp including Ohnuma and Konuma, highland swamp flora is left in part.
