目的 了解蓬莱区农田土壤重金属含量,评价土壤污染状况。方法 采用分层随机抽样方法,于2011—2020年在蓬莱区每年选取20个不同监测点,每个监测点采集村中农田土壤1份,共采集200份土样进行铅、镉、铬的测定。依据《土壤环境质量农用地土壤污染风险管控标准(试行)》(GB 15618—2018),采用累积指数法、单因子污染指数法、内梅罗综合污染指数法评价铅、镉、铬的污染程度。结果 2011—2020年,不同年份土壤Pb含量差异无统计学意义(H=16.626,P=0.055),而Cd、Cr含量差异具有统计学意义(H_Cd=31.882,P＜0.001;H_Cr=2.750,P=0.015)。其中38份土壤镉含量超出农用地土壤污染风险筛选值;单因子污染指数分析,土壤中镉污染最为严重;内梅罗综合污染指数评价显示,监测区大部分土壤存在轻度污染,小部分土壤存在中、重度污染。 结论 蓬莱区部分农田镉污染较重,应加强防范,减少土壤镉污染。

Objective To understand the heavy metal content of agricultural land soil in Penglai District,and to evaluate the soil pollution status. Methods Using stratified random sampling method,20 different monitoring sites were selected in Penglai District each year from 2011 to 2020,and one copy of soil was collected from each monitoring site in the village agricultural land.Finally,a total of 200 soil samples were collected for the determination of lead (Pb),cadmium (Cd) and chromium (Cr).According to the Soil Environmental Quality: Risk Control Standard for Soil Contamination of Agricultural Land (Trial) (GB 15618—2018),the pollution levels of Pb,Cd and Cr were evaluated by cumulative index method,single factor pollution index method and Nemerow Comprehensive pollution index method. Results The differences in Pb content in soil between years were not statistically significant (H=16.626,P=0.055),while the differences in Cd and Cr content were statistically significant (H_Cd=31.882,P＜0.001;H_Cr=2.750,P=0.015) from 2011 to 2020.The content of Cd in 38 soil samples exceeded the risk screening value of agricultural land in the study area.The single factor pollution index analysis showed that Cd pollution was the most serious in soil.Nemero Comprehensive pollution index evaluation showed that most of the soil were slightly polluted,and a small portion were moderately or heavily polluted in the study area. Conclusion The Cd pollution of some agricultural land in Penglai District is serious.Therefore,the prevention of Cd pollution should be strengthened.