Acta Geographica Sinica ›› 2017, Vol. 72 ›› Issue (9): 1680-1694.doi: 10.11821/dlxb201709012

• Orginal Article • Previous Articles     Next Articles

Assessment of heavy metal pollution and its potential ecological risks of farmland soils of oasis in Bosten Lake Basin

EZIZ Mamattursun1,2(), MAMUT Ajigul1, MOHAMMAD Anwar3, Guofei MA1   

  1. 1.College of Geographical Science and Tourism, Xinjiang Normal University, Urumqi 830054, China
    2. Xinjiang Laboratory of Lake Environment and Resources in Arid Zone, Xinjiang Normal University, Urumqi 830054, China
    3. College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, China
  • Received:2016-11-14 Revised:2017-05-19 Online:2017-09-30 Published:2017-09-30
  • Supported by:
    National Natural Science Foundation of China, No.41561073;Fund for Training Program of Distinguished Young Scientists of Xinjiang, No.qn2015jq003


A total of 195 soil samples of farmland were collected from oasis in the Bosten Lake Basin, Xinjiang, and the concentrations of eight heavy metal elements (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) were identified by standard methods. The spatial distribution of soil heavy metals in farmland was analyzed based on geostatistical analysis, while the pollution load index (PLI) and potential ecological risk index (RI) were employed to the assessment of the soil heavy metal pollution levels and potential ecological risk. Then the main sources of heavy metals were discussed. Results showed that: (1) The average value of the contents of Cd, Cr, Cu, Ni, Pb and Zn exceeded by 1.67, 1.13, 1.15, 1.29, 2.11 and 1.65 times of the soil background value of Xinjiang, respectively. (2) The spatial distribution of eight heavy metals showed an island-like pattern, and all the heavy metal elements showed high value areas in some parts of the study area, indicating the negative effects of human activities on soil environment of farmlands. (3) Pb presented a moderate pollution, whereas Cd, Zn, Ni, Cu and Cr a light pollution, Mn a slight pollution and As no pollution for farmland soils. The average PLI value of the heavy metals was 1.09, which showed a slight pollution. (4) The average E value for each heavy metal element was ranked as: Cd > Ni > As > Cu > Pb > Cr > Zn. The average RI value was 18.63, which showed a slight ecological risk situation. In terms of regional differences, the ecological risk index was ranked as: Hoshut County > Baghrash County > Karashahar County > Hejing County. (5) Cr, Cu, Mn, Ni and Zn contents were controlled mainly by the soil geochemical genesis and As, Cd and Pb were mainly affected by human activities. Cd and Pb were the main pollution sources of farmland soils, which should be given more attention.

Key words: farmland, soil heavy metal, pollution assessment, ecological risk, Bosten Lake Basin