Abstract: Based on the standard of agricultural soil pollution risk management and control,the potential ecological risk index method was used to evaluate the risk of farmland soil pollution and the quality of the soil,which provided a theoretical basis for farmland soil risk management and control in the North Urad Irrigation Area of Hetao Irrigation Area.The results showed that the content of Cd,Hg,As,Pb and Cr in the soil of the survey area was lower than the risk screening value of soil pollution risk management and control,indicating that the risk of soil pollution was low,and the safe use of agricultural land is subjected to the priority protection.Compared with the regional soil background value,except for Cd,the average content of the other four heavy metals were all lower than the background value,but the content of Cd,Pb and Cr in some sites exceeded the standard,and the exceeding rate was respectively 54.5%,15.2% and 21.4%.The average value of the single potential ecological risk index of Cd,As,Pb,Cr and Hg was 8.39,0.93,0.40,0.38 and 0.28,respectively from high to low,and the average value of the comprehensive potential ecological risk index was 10.39.The potential risk index also showed that the risk of farmland soil pollution in the survey area was low,which is at a slight ecological risk level.

Key words: Urad Irrigation Area, Soil pollution, Farmland soil, Ecological risk, Risk management and control, Heavy metal