高速公路路面沉积物的污染特性

对湖南省长潭西高速公路不同采样点的路面沉积物进行取样分析,并检测了样品的颗粒级配、COD、重金属(Cu、Zn、Pb和Cd)和有机质。结果表明,路面沉积物主要以粒径<0.15 mm的颗粒为主;较小颗粒物中的COD含量高于较大颗粒中的COD含量;粒径在0.15 mm以下的颗粒物所含重金属Cu、Zn、Pb和Cd的浓度普遍高于所选的土壤标准值,降雨一旦形成径流将会产生严重的污染危害;沉积物中的有机质含量对重金属的吸附有一定的影响,有机质含量越高,沉积物中重金属含量相对也高。

Pollution features of highway road sediments

The particle size distribution, COD, heavy metals (Cu, Zn, Pb, Cd) and organic matters of road sediments were analyzed at different sampling points of West Changtan Highway in Hunan. The results showed that the particle size distribution of sediments was generally less than 0.15 mm and the content of COD in smaller particles was higher than that of larger particles. The concentrations of heavy metals (Cu, Zn, Pb, Cd) in particles with diameter less than 0.15 mm generally exceed standards of the selected soil. Hence, serious pollution would be caused by storm runoff. The content of organic matters in sediments had certain influence on adsorption of heavy metals. The higher content of organic matters was, the higher content of heavy metals would be.