Soil contamination by heavy metals in Jinan City and its biological characteristics

Abstract：The contamination characteristics of heavy metals in urban and rural soil of Jinan City were investigated in this paper, and the results show that heavy metal contamination not only causes deterioration of ecological environment but also reduces soil biodiversity and activity. Meanwhile, the correlation between the number of animal population and the heavy metal content was analyzed statistically, and the results indicate that there is significantly negative correlation either between the number of soil protozoa and the concentration of Co and Ni or between soil nematode amount and Cu and Mo content. So does the correlation between drought–tolerant animal amount and Cu content. On the one hand, these data imply that heavy metals can cause damage to soil biodiversity; on the other hand, the conclusion can be reached that soil nematodes are of pollution-tolerant species while drought–tolerant animals are not. It is thus believed that the density ratio between them can indicate the contamination degree of soil heavy metals. Moreover, sensitive biological indicators of heavy metals were detected by analyzing the correlation between geological element concentrations and biological parameters of soil. For example, soil nematode is a biological indicator of Pb contamination, and PLFA (epiphyte) can indicate As pollution. The authors hold that using soil organisms as indicators of heavy metal contamination has wide application prospect.