To evaluate the heavy metal contamination of soil and plants in Dunhua sewage irrigation area (DIA),the area used wastewater for irrigation at least 20 years. 270 samples in different depth (0-120 cm) and23 plant samples were collected at five different sites. Physical and chemical properties of the long- term sewage irrigation soil were analyzed, including soil texture, bulk density, pH, cation exchangecapacity (CEC), organic matter; the heavy metal total concentrations were measured using AAS andAES. The average value of soil pH was 8.01, the soil was alkaline; the soil CEC changes from 59.35mmol to 118.95 mmol, average value was 80.96 mmol; content of organic matter in surface soil3 maintained 1.27% to 2.18%; the bulk density of soil ranges from 0.94 to 1.57 g/cm ; averageconcentrations of heavy metals in surface samples were: Cr, 28.249 mg/kg; Cd, 1.247 mg /kg; Pb,37.468 mg/kg; heavy metal concentration in the three different crops of different portions was:root>stem>leaf>grain; the vertical distribution and migration the concentration of 0-20 cm soil wassignificantly higher than other soil layers, showing the characteristic of enrichment at surface,relatively stable in deep. Heavy metals pollution degree was Cd(2.069)>Cr(0.113)>Pb(0.107),pollution risk degree of different sample point range was EC>MF>Xg>WD>XG. Irrigation bywastewater has increased the heavy metal concentrations in soil and plants of receiving area.
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