【摘要】 重金属因其不易降解、易于在生物体富集和造成二次污染而成为一种重要的环境污染源.对公路旁侧土壤污染最严重的2种重金属铅和镉沿公路垂向的水平迁移及其在公路旁侧土壤中的纵向迁移进行研究,以期为公路沿线农业生态安全提供理论依据.土样中的铅镉含量用原子吸收法测定,铅、镉的生态危害指数用HaKanson的生态危险指数法进行评价.研究表明,铅、镉沿公路垂向的水平迁移距离约为40～60m;二者在土壤中的纵向迁移距离约为20cm.芜(湖)—铜(陵)高速公路繁昌段铅水平已接近轻微污染水平;镉污染则比较严重,各样点镉含量均超出国家环境质量一级标准的上限,其单项污染指数及潜在生态危害单项指数均达到轻微至中等生态危害水平.建议公路沿线两侧不宜种植食根粮食作物与蔬菜.更多还原

【Abstract】 Heavy metals are important environmental pollutants due to their un-decomposability,easy accumulation in biomass and secondary contamination.The current study focused on the horizontal and vertical migration of two important pollutants of Lead and Cadmium in the roadside soils along a highway in order to supply theoretical basis for ecological highway agriculture.Meanwhile,the ecological risk of lead and cadmium by using HaKanson’s index was evaluated results indicated that the horizontal migrating distance of lead and cadmium along the vertical orientation of Wuhu-Tongling highway is about 40～60 m,whereas the distance of vertical migration of both heavy metals in roadside soil is about 20 cm.The roadside soil along Wuhu-Tongling highway has been slightly polluted by lead.The pollution of cadmium,however,is even more serious.The content of cadmium in any of the sampling sites is higher than the upper limit of nation standard of environment quality (grade I).Both the individual pollution index and the potential ecological risk of individual pollution index are approaching to a level of slight-middle ecological risk.In accordance with the present findings and related results available,root-orientated crop plants and vegetables are not suitable to grow in the roadside.更多还原