扬州古运河沉积物污染物释放强度与特征研究  

Study on contaminant release intensity and characteristic of sediment of Yangzhou ancient canal

作　　者：王改[1] 黄廷林[1] 周真明[1,2] 董玉华[1] 辛清梅[1] 徐金兰[1] 

机构地区：[1]西安建筑科技大学环境与市政工程学院,陕西西安710055 [2]华侨大学土木工程学院,福建厦门361021

出　　处：《环境污染与防治》2012年第11期25-29,共5页Environmental Pollution & Control

基　　金：国家水体污染控制与治理科技重大专项(No.2009ZX07317-007-1-2)

摘　　要：研究了扬州古运河沉积物中氮、磷、铁和锰等污染物释放强度与特征,着重考察了上覆水中DO和污染物负荷对污染物释放强度的影响,分析了氮、磷、铁和锰等污染物释放条件。结果表明:扬州古运河有一定的自净能力,且呈现初期释放NH4+-N、后期转化为NO3--N的特征;随着水环境条件改变,沉积物NH4+-N、PO34-、铁和锰平均释放强度变化范围是123.14～445.68、13.50～32.45、25.20～198.47、19.97～25.02mg/(m2.d);上覆水DO浓度越低,污染物平均释放强度越大;上覆水污染物浓度越小,污染物(除铁外)平均释放强度越大;在DO<5mg/L条件下,沉积物向上覆水释放NH4+-N;在DO<1mg/L条件下,沉积物向上覆水释放PO34-、铁和锰;在DO为2～5mg/L条件下,上覆水PO34-和铁向沉积物中汇入,但锰则呈现释放和汇入的交替变化。The release intensity and characteristic of contaminant such as nitrogen, phosphorus, iron and manga- nese from sediments of Yangzhou ancient canal were investigated, the effects of DO concentration and contaminant load on contaminant released intensity were specially studied, meanwhile, the release conditions of contaminant were analyzed. The results showed that Yangzhou ancient canal had certain self-purification capacity; the ammonia nitrogen was initially released from sediment and later transformed into the nitrate nitrogen. As the change of water environ- ment elements, the average release intensity of nitrogen, phosphorus, iron and manganese from sediment was 123.14 445.68,13.50-32.45,25.20-198.47,19.97-25.02 mg/（m2· d） ,respectively. The lower the DO concentration or the higher the contaminants load of overlying water,the higher the contaminants releasing intensity. Nitrogen contaminant of sediments was released into the overlying water when the DO less than 5 mg/L; phosphorus,iron and manganese contaminant were released from sediments when the DO concentration less than 1 mg/L. When DO was 2-5 mg/L, phosphorus and iron contaminant in the overlying water were absorbed into sediments, however, manganese contami- nant behaved alternately released into the overlying water and absorbed into sediments.

关 键 词：沉积物 污染物释放 释放强度 扬州古运河 

分 类 号：X524[环境科学与工程—环境工程]