Abstract:

In this paper, the pollution of anomalous elements in soil in MinheHaishiwan，Qinghai and its potential ecological hazard were evaluated quantitatively through single factor pollution index method, Nemerow pollution index method and Hakanson potential ecological risk index method. Additionally, the ecological effect in anomalous areas was also discussed. The results show that the pollution factors of heavy metals are in order of Hg＞Cd＞Pb=Cr in the soil. The bioavailability of the anomalous elements follows the sequence of Cd＞Hg＞Pb. The potential ecological hazard of anomalous elements was as follows: Hg＞Cd＞Pb＞Cr. Although the concentration of anomalous elements in crops such as wheat and corn was far below the required food security limits, the situation of pollution control was still severe due to the high potential ecological hazard of Hg and high bioavailability of Cd.

Key words: multipurpose regional geochemical survey, Nemerow pollution index, potential ecological risk index, heavy metals in soil, MinheHaishiwan, Qinghai