ZN AND FE CONTAMINATION INDEX FOR RIVER USING RIVER INSECTS AND WATER PLANTS IN THE KINOKAWA RIVER CATCHMENT.

It has not been studied whether river insects and water plants are useful for an index of Zn and Fe contamination in the Kinokawa River catchment. Useful species as an index of Zn and Fe contamination needs a high concentration in a contaminated area, a low concentration in a non-contaminated area and a high and a wide range of their concentrations. Zn and Fe concentrations of crane fly larva around the closed Cu mine were high (88 to 420 and 1,300 to 9,300 mg/kg-dry for Zn and Fe). Zn and Fe concentrations of bryophyte around the closed Cu mine were high (34 to 8,900 and 110 to 58,000 mg/kg-dry for Zn and Fe). Crane fly larva (81 to 420 and 110 to 9,300 mg/kg-dry for Zn and Fe) in river insects and bryophyte (24 to 8,900 and 110 to 58,000 mg/kg-dry for Zn and Fe) in water plants had high and a wide range of Zn and Fe concentration. Therefore, it was thought that crane fly larva and bryophyte were useful species for an index of Zn and Fe contamination. Zn concentrations of Pottiaceae and Fe concentrations of Brachytheciaceae around the Cu mine area (75 to 8,900 for Pottiaceae and 940 to 58,000 mg/kg-dry for Brachytheciaceae) were high. Pottiaceae (75 to 8,900 mg/kg-dry for Zn) and Brachytheciaceae (220 to 58,000 mg/kg-dry for Fe) had high and a wide range of metal concentration. Therefore, Pottiaceae for Zn and Brachytheciaceae for Fe were useful species for an index of metal contamination. [ABSTRACT FROM AUTHOR]