Contaminative Conditions Of Main Sixteen Rivers Around Bohai Sea And Pollutant Flux Flowing Into Sea In Summer Of 2005

The land and ocean interaction has been the focus of global environmental changes research. Water quality and pollutant flux of rivers flowing to rivers which are regarded as central questions of land influencing ocean have increasing come to people's attention. The Bohai Sea is an only typical enclosed surrounded by Chinese mainland and supports economy development of areas around Bohai Sea. The rivers flowing into sea are the main pollution origin of coast area. Meanwhile, riverine carbon flux is an important joint constituting global carbon cycle. Therefore, pollutant flux flowing into sea of rivers around Bohai Sea is significative to administer Bohai's environmental pollution and perfect global carbon system database. The conclusions are following:1.Among sixteen rivers around Bohai sea, there are four rivers whose water quality isⅣclass, one river whose water quality isⅤclass, eight rivers whose water quality is lessⅤclass and only three rivers whose water quality isⅡclass. Liuguhe river'water quality is better than any other rivers and Ziyaxinhe river'water quality is worse than any other rivers. By analyzing the sharing ratio of pollution, the first is petroleum which is the key pollutant of eleven rivers, the second is nutrients, and the third is permanganate index.Seven rivers such as Daliaohe river,yellow river and so on are eutrophic, the other seven rivers such as Xiaoqinghe River and Jiyunhe River and so on are extreme-eutrophic. As a result, the eutrophic conditions of rivers around Bohai Sea are far serious. The organic pollutant investigation indicated that the average concentration of TOC in sixteen rivers is 16.41 mg/L, the average permanganate index is 6.04 mg/L, the average weight percentage of the readily biodegradable organism in total is only 15.18%, which suggests that total organic pollution is quite serious. 2. In summer of 2005, the pollutant flux flowing into sea of yellow river basin,which is 98757t, is most; the pollutant flux of Liaohe river basin, which is 61499t, is next; the pollutant flux of Haihe river basin, which is 34035t, is least.3.In summer of 2005, the PAHs in TSS of Shuangtaizihe river is 25.41mg/kg; the PAHs in TSS of Jiyunhe river is 17.59mg/kg; the PAHs in TSS of Dalinghe river is 32.43mg/kg; the PAHs in TSS of yellow river is 1.64mg/kg. As a result, the PAHs in TSS of Dalinghe river is most, and yellow river is least.4. The DOC in sixteen rivers around Bohai Sea mostly originates from the wastes which are generated by human; The POC of Ziyaxinhe, Chaobaixinhe, Xiaoqinghe, Xiaolinghe, ,Haihe, ,Majiahe and Luanhe mostly originates from the wastes which are generated by human, the POC of Daliaohe, Huanghe, Shuangtaizihe, Tuhaihe, Dalinghe, Daqinghe and Liuguhe mostly originates from soil erosion. The DIC concentration of Ziyaxinhe, Chaobaixinhe, Xiaoqinghe, Duliujianhe and Jiyunhe is high because of industrial alkali's massive discharge and its lower recovery rate. In addition, the DIC and eutrophication have the same source.In summer of 2005, the average concentration of DOC in sixteen rivers is 8.66mg/L; the average of POC is 7.88 mg/L; the average of DIC is 44.07mg/L; the average of pCO2 is 2032μatm. In summer of 2005, the carbon flux flowing into Sea of rivers around Bohai Sea flowing into Sea is 7.37×10~5t. Analyzing carbon flux in terms of river basin, the result shows that the carbon flux of yellow river basin, which is 3.07×10~5t and accounts for the total 42%, is most; the carbon flux of Liaohe river basin, which is 2.46×10~5t and accounts for the total 33%, is the second; the carbon flux of Haihe river basin , which is 1.84×10~5t and accounts for the total 25%, is the least. In short, the carbon flux of yellow river basin flowing into Bohai Sea is the most, but he carbon flux of Haihe river basin should be put attention to.