Evaluation Of Soil Pollution And Accumulation Characteristics Of Heavy Metals In Crops Around Yangzonghai Thermal Power Plant

Taking Yangzonghai Thermal Power Plant in Kunming City as the sampling area for soil and crop sampling survey,the contents of Pb,Zn,Ni,Cu,Cd,Cr,As,Hg in soil and crops were determined and analyzed.The results showed that the Hg content in the soil exceeded 4.14 times relative to the background value,and the Cr content exceeded 1.06 times relative to the background.From the Nairobi comprehensive pollution index,the Cd in the study area had reached moderate pollution in the soil;the results of the potential risk index showed that Cd The highest value of ecological risk coefficient is 132.3 at 50 meters,and the highest is 351.2 at 500 meters;correlation analysis results show that Ni,Cd,Cr,As and other heavy metals are significantly correlated(P <0.01)and Ni,Cd,Cr and As are significantly correlated with each other(P <0.01).In the study area,corn,butter beans,and cabbage were all contaminated with heavy metals to varying degrees.Among them,Cr,Zn,Hg,Cr in corn,Cr,Zn,Hg in butter beans,and Zn and Cr in cabbage all exceeded the national pollutant limits for food safety.The calculation of BAC and BTC on the roots,stems and leaves of crops shows that the maize roots have a strong absorption and enrichment capacity for Cd and Hg,and the transfer capacity of butter beans to heavy metals is higher than that of other crops.Correlation analysis of heavy metal content in crop soil showed that corn and cabbage were positively correlated with Ni and Cr in soil(P <0.05),indicating that most of Ni and Cr in corn and cabbage came from soil,and the correlation between Cr in cabbage leaf soil was significant(P <0.01).Ni,Cr and Cd in butter bean soil were correlated(P <0.05),indicating that most of Ni,Cr and Cd in butter bean came from soil.