Investigation and Fuzzy evaluation of the organic pollution in Songhua River in Jilin City

The research team investigated the drain contamination on the coast of Songhua River from Songhua Lake to Jiuzhan Station.Then 14 monitoring sections were set according to the distribution of the 93 drainage outlets and the characteristics of the Songhua River in Jilin City.Meanwhile,each section had been monitored in the Dry season,Wet season and General water season on the water quality factor of NH3-N,TP,CODMn,BOD5 and DO,etc.Afterwards fuzzy evaluation method was applied to evaluate the monitoring results.The evaluation results indicated that there exist certain degrees of organic pollution as well as some monitoring sections of which the water quality was not up to the standard of the function area.