EZIZ Mamattursun1, MAMUT Ajigul1, MOHAMMAD Anwar2
(1.College of Geographical Science and Tourism, Xinjiang Normal University, Urumqi 830054, China;
2. College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, China)
Abstract：Total of 82 farmland soil samples were collected from Hoshut oasis, Xinjiang Autonomous Region, China, and contents of eight heavy metal elements (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) were determined by standard methods. Heavy metal pollution level and potential ecological risks of farmland soils were analyzed based on geostatistical analysis, pollution load index (PLI) and ecological risk index (RI), and the main sources of heavy metals were also discussed. Results indicate that: ① The average contents of all elements in farmland soils of Hoshut oasis have not exceeded the National Soil Environmental Quality Standard (Grade II). Average contents of Cd, Cr, Ni, Pb and Zn exceed 2.0, 1.51, 1.18, 2.13 and 8.47 times of the background values for irrigation soil of Xinjiang, respectively; ② Cd and Pb fell into moderate pollution level, whereas Cr, Cu, Ni and Pb fell into light pollution level, with slightly pollution of Mn and no pollution of As for farmland soils. Average PLI value of heavy metal in farmland soil shows a light pollution level; ③ Average value of individual ecological risk index for each heavy metal elements of farmland soil from high to low follow the order as Cd, Ni, As, Cu, Cr, Zn and Pb. Average RI value shows a slight ecological risk situation. The spatial distributions of heavy metal contents, pollution levels and potential ecological risks are different; ④ As, Pb and Zn in farmland soil are affected mainly by human activities. Cr, Cu, Mn and Ni are affected mainly by geochemical background of soil. Cd may be affected by the interaction of human activities and natural factors. Cd is one of the main pollution factors for farmland soil that has considerable influences on contamination and ecological risks of farmland soils. Cd pollution in farmland soil should be a major concern.
Key words：soil heavy metal；pollution assessment；ecological risk；spatial analysis；Hoshut oasis
EARTH AND ENVIRONMENT Vol.46, No.1, Tot No.321, 2018, Page 66-75
