river pollution
4.During1996～2000,the pollution of heavy metal in bottom mud in Harbin part of Songhua river was researched,and it was found that the difference was not visible between each broken surface of Songhua river. The pollution of Ashi river was heavier than it of Songhua river,and the pollution of Hulan river was as heavy as it of Songhua river.
7.WATER POLLUTION CONTROL PLANNING OF YONGTZE RIVER AND JIALING RIVER IN CHONGQING
