PROGRESS IN GEOGRAPHY ›› 2012, Vol. 31 ›› Issue (5): 632-638.doi: 10.11820/dlkxjz.2012.05.012

• Original Articles • Previous Articles     Next Articles

Spatial Distribution and Potential Ecological Risk Assessment of Heavy Metals in Roadside Soils along the Lianyungang-Horgas Highway

GU Lei1,2, SONG Bo1,2, TONG Zhiqi1,2, MA Jianhua1,2   

  1. 1. Institute of Natural Resources and Environment, Henan University, Kaifeng 475004, China;
    2. Henan Open Laboratory for Key Subjects of Environmental Change and Water-Soil Pollution Control, Henan University, Kaifeng 475004, China
  • Received:2011-07-01 Revised:2011-10-01 Online:2012-05-25 Published:2012-05-25

Abstract: On Lianyungang-Horgas highway, two typical sampling transects along the Zhengzhou-Shangqiu section,Wanliu transect operated in 1994 and Xiaowangzhuang transect operated in 2001, were chosen to investigate the distribution and potential ecological risks of heavy metals (Cd, Cu, Pb, Zn, Ni, and Cr) in roadside soils.Soil samples were collected at different distances from the highway. The contents and spatial distribution ofheavy metals in the soils were analyzed. The ecological risks of soil heavy metals were evaluated based on potential ecological risk index (RI) put fowward by Håkanson. The results show that heavy metal concentrations and potential ecological risks on Wanliu transect (at moderate ecological risk level) were higher than those on Xiaowangzhuang transect (at slight ecological risk level) because of longer operated time. Most of the heavy metal concentrations and potential ecological risks present a skew distribution with the distance from highway roadbed. The highest risk indexes for different metals on Wanliu transect are observed at 50~100 m from highway roadbed, while those on Xiaowangzhuang transect at 35 m from the roadbed. The total risk index was mainly contributed by cadmium with the averagely proportion of 61.39% (ECd/RI). Therefore cadmium is the mainfactor influencing potential ecological risks. Potential ecological risk index is a rigorous method, because it includesnot only concentrations of heavy metals, but also ecological effects and toxicological characters. To applythe method of RI in estimating the potential ecological risk of pollutants, the RI standards for different levels of potential ecological risk should be modified according to the pollutant amounts studied and their toxic-response factors.

Key words: different operated time, heavy metals, Lianyungang-Horgas Highway, potential ecologicalrisk, roadside soil