The relationship between the concentration of arsenic and the hydraulic gradient along the shallow groundwater flow-path of Hetao plain, Northern China

摘要

In order to better understand the relationship between the concentration of arsenic and hydraulic gradient along the shallow groundwater flow-path in Hetao plain, we chose three paths which are established along the groundwater flow direction and collected 231 shallow groundwater samples from the three paths. The result shows that: arsenic concentrations and speciation exhibit systematic changes along the flow path. The hydraulic gradient of the groundwater plays a great role in promoting arsenical enrichment. In the runoff and recharge area of Hetao plain, if hydraulic gradient of groundwater is less than 0.79%o, the concentration of arsenic would be more than 10 g/L. But in the discharge area, the hydraulic gradient and the concentration of arsenic are completely unrelated.