Water Pollution Trend in Shanghai Seacoast

The pollutants in Shanghai sea area come mainly from the Yangtze river, Huangpu river and city wastewater discharging in coast.To research water pollution trend in Shanghai sea coast,the data of Shanghai water qualities are extracted from authorized communiques and reports on ocean,environment and water in 1981-2006,which include pollutant discharge of city wastewater,Yangtze river and Huangpu river.It can be found that the city wastewater,which includes industry wastewater and living wastewater,was around 1775～2420 million tons per year in past 25 years.The industry wastewater was decreasing by years.The concentrations of cyanide,heavy metal and arsenic in the industry wastewater has been controlled to a low level from 2000.The living wastewater has been increasing by years for past 25 years.The main pollutant in living wastewater was organic compound.There was relationship between discharge of living wastewater and population.The averaging living wastewater per person-year was increase 2.7 times in past 25 years,the largest increasing ratio in one year on living wastewater per year was 25%.The discharge pollutant flux in month from the Yangtze river was around 0.259～2.096 million tons in recent years,with the minimal at the end of winter and maximal in the summer.The difference between winter and summer was 2.3～8.1 times.There was relationship between discharge pollutant flux and runoff in the Yangtze river for seasons,but no relationship for years.The discharge pollutant flux from Huangpu river is about 1.2%～4% from the Yangtze river contemporarily.In the pollutants discharged to Shanghai sea-area in recent years,the organic compound from city wastewater was about 8%～25% from the Yangtze river,the heavy metal from city wastewater was less than 0.03% from the Yangtze river.The pollutants in Shanghai sea-area were mainly nitrogen compound,phosphate and oil.The pollution in Shanghai sea-area was the most seriously around China coast.The pollution would be increasing at Shanghai sea-area with increasing population in Shanghai city and around areas.