Abstract:

Hetao Plain is a typical kind of irrigated agriculture area in Inner Mongolia. This study focused on the Tuoketuo area located in the eastern part of Hetao Plain. Totally 1,564 samples of the surface soil were analyzed based on the GeoExpl system, and eight heavy metal elements including Cd, Hg, As, Cu, Pb, Cr, Zn and Ni in the top soil were analyzed. Among these heavy metal elements, the maximum of variable index is Hg and the minimum of it is Pb. The high concentration of these heavy metal elements has been found in the northwestern part of the study area. Based on these data, a fuzzy comprehensive assessment is carried out. The results can reasonably reflect the region’s soil quality. The paper concludes that the soil in the Tuoketuo area is not contaminated by heavy metals while it is high in some area, especially along the Heihe River area. Irrigation and the improper usage of pesticides and chemical fertilizers containing heavy metals are considered to be the cause of the heavy metal contamination in the soil.

Key words: heavy metal contamination, fuzzy comprehensive assessment, Tuoketuo area in Inner Mongolia