Heavy metal characteristics and ecological risk assessment of soil in the hilly river type drinking water source protection area in central Sichuan
In order to study the distribution characteristics,sources,and ecological risks of heavy metals in the soil of the river type drinking water source protection zone in the red layer hilly area of central Sichuan,a total of 40 surface soil samples were collected from the Mengxi River centralized drinking water source protection zone,and the distribution characteristics and differences of heavy metals were statistically analyzed.Correlation analysis,cluster analysis,and principal component analysis were used to study the sources and influencing factors of heavy metals.Single factor pollution index was used ecological risk assessment of heavy metals in soil of water source protection areas based on land accumulation index and potential ecological risks.The results showed that the average content of heavy metals in the soil of the study area was Cr>Ni>Pb>Cu>As>Cd>Hg.Among them,the average content of Cu and Cd in the first level protection zone was higher than that in the second level protection zone,while the average content of Cr,Ni,Pb,As,Hg in the second level protection zone was relatively higher.The main source of heavy metals in soil is the soil parent material,and they are also affected by human agricultural production activities.Cu,Cd,Ni,Pb,As,Hg,and Cd in the soil of the first level protection zone did not exceed the standard,while Cd elements in the soil of the left bank of the second level protection zone exceeded the standard at two points,with a small multiple of exceeding the standard.The comprehensive potential risk index rated it as a slight ecological hazard,with Cu,Ni,Pb,As,and Cr being low risk.Only Cd and Hg have medium and high risks,and there is no distribution of high and extremely high risk levels.Among them,Cd produces a higher risk,accounting for 2.5%,and Cd and Hg will not have an impact on the ecology.In addition,based on historical monitoring data of water quality in the water source area,it is difficult for heavy metals in the soil within the water source protection zone to have an impact on the safety of drinking water source water quality.
Water source protection areasoilcharacteristics of heavy metalsecological risk
NETL
NSTL
万方数据
