Abstract: The study with pot culture experiment showed that Equisetum ramosissimum did not appear obvious poisoning symptoms when treated with low concentration Cu (500 mg·kg^-1),while serious injuries were found when treated with high concentration Cu (1 000～3 000 mg·kg^-1),which reflected in the severe damage of cell membrane and cytoarchitecture as well as the structure and function of main organelles,and the significant decrease of the contents of leaf chlorophyll a and b and stem soluble monosaccharose.The cell membrane osmolarity and the average MDA content of the plant exposed to heavy copper pollution was 1～2 and 1～3 times greater than the control,respectively.It could be concluded that high concentration Cu disturbed the physiological metabolism,and critically threatened the normal growth of E.ramosissimum.The activities of protective enzyme,especially of SOD and POD,were enhanced with increasing Cu concentration,and had a positive correlation with Cu concentration (r_POD=0.978,r_SOD=0.926,P<0.05).

Key words: Okhotsk Sea, Walleye pollock, Distribution, Environment of fishing ground