Soil Heavy Metal Pollution and Risk Evaluation in Black Soil Areas of Heilongjiang Province
In order to investigate the current status and ecological risk of soil heavy metal pollution in the black soil areas of Heilongjiang Province,we collected samples(N=303)of top soil(0～15 cm)from farmland in the black soil areas,and then detected the heavy metal content and pH value of the soil samples.Soil heavy metal pollution level and ecological risk in the study area were thereby evaluated by using the ground accumulation index approach,potential ecological risk index method and geo-statistical method,and traceability analyses were carried out by use of the APCS-MLR(absolute principal component scores-multiple linear regression)model and PMF(positive matrix factorization)model.The findings of the inves-tigation showed that the soil in the study areas was mainly weakly acidic,and the concentrations of the heavy metals:Cr was(50.60±9.16)mg/kg,Ni(18.35±5.25)mg/kg,Cu(26.49±6.35)mg/kg,Zn(55.71±12.26)mg/kg,As(11.73±3.75)mg/kg,Pb(20.47±5.12)mg/kg and Cd(0.13±0.077)mg/kg,and concentrations of all these heavy metals(except for Cd)did not exceed the related national standard,the concentration of Cd in 3％of the black-soil points being monitored had exceeded the standard about soil contamination risk screening value of agricultural land,furthermore the results of geocumulative index showed that Cd pollution dominated the areas with a pollution rate of 41％,and the result obtained by potential ecological risk index method indicated that Cd was the main risk factor,and the mean value of RI(i.e.,comprehensive potential ecological risk index)was 77.10 so the risk was low.As for the pollution sources,the analytic result of APCS-MLR was consistent with that of PMF model,which suggested three pollution sources,namely,the mixed natural/traffic sources,the agricultural sourc-es,and the industrial sources;according to APCS-MLR,the above-mentioned pollution sources'contributions accounted for 42.02％,15.70％and 14.82％,respectively,while according to PMF model,37.64％,28.82％and 33.54％,respectively.In con-clusion,the environmental quality of soil in the black soil areas of Heilongjiang Province is fine,but the potential pollution risk of Cd should be paid attention to.
black soilheavy metalspollution assessmentecological risk assessment
万方数据
维普
