Research On Heavy Metals Pollution In Soil And Sediment Of The Aojiang River Basin

Since the reform and opening up,with the rapid development of China’s economy,in recent years,industrial pollution emissions continue to intensify,Wenzhou Aojiang River pollution is becoming increasingly serious.Wenzhou Pingyang County was the largest raw leather processing base in China.With hundreds of years of leather processing history,it has caused great damage to the water environment.Therefore,it is necessary to carry out its water environment research.In this paper,field sampling and laboratory analysis were used to collect the soil and surface sediments of the Aojiang River Basin,and the total amount was 62,and the total amount of the samples was 10.The contents of Cr,Ni,Cu,Zn and Pb were investigated and investigated.In this paper,the watershed is divided into three sections: non-industrial area,industrial agglomeration area and seawater tide area,and the spatial distribution and correlation analysis are carried out.From the Nemero index method,the cumulative index method,the potential ecological hazard index method And pollution load index method were used to evaluate the pollution of soil and surface sediment in each river bank of the study area.At the same time,through the study of the heavy metal of dyestuff dyeing and dyeing,it is judged whether there is heavy metal damage and whether it is related to the heavy metal content in the soil and sediment of the river basin,and then the pollution source is analyzed.Finally,The Research indicates:(1)Through the study of the dyeing and finishing of leather,it is found that Cr is a major pollutant in the dyeing and finishing of leather and has a strong ecological hazard and needs to be properly treated.Otherwise,it will seriously pollute the environment.(2)The content characteristic analysis found that: the aojiang river middle reaches of industry clusters and with heavy metal enrichment degree is higher,the brook in 3 different sections of high concentration of Cr content.(2)The results showed that the enrichment of heavy metals in the middle reaches of the Aojiang River Basin and the heavy water in the Xihe River Basin were higher than those in the non-industrial zone and the seawater region,and the Cr content was highly enriched.(3)The distribution characteristics and correlation analysis showed that the trend of heavy metal content in the basin showed a trend of increasing from non-industrial area to industrial agglomeration area,and then the trend of seawater tide area decreased.It is determined that the high concentration of Cr,Cu and Zn in the soil and sediment of the industrial agglomeration area is derived from the waste residue discharged from the tanning industry,and the correlation between Cu and Ni is from the local electroplating industry.The reason for the decrease of heavy metal content in seawater tide area is due to the intrusion of sea water in Haikou,dilute the soil and sediment in this section.(4)Evaluation of heavy metal pollution: The comprehensive pollution index method,the cumulative index index method and the potential ecological risk index method all point to the most serious heavy metal pollution in industrial agglomeration area,and the contribution of Cr pollution in each element is the largest;the pollution load index method is more The ecological risk index method further refined the comprehensive pollution situation at each sampling point,and the trend of pollution change was consistent with the distribution trend of spatial content obtained in the above analysis.The middle reaches of Aojiang River and Zuoxi Strong pollution or strong pollution,the urgent need to take appropriate measures.