Research On Pollution Characteristics And Risk Assessment Of Heavy Metal In Soil Of Urban Fringe Area

In the rapid development of urbanization,the soil has been suffering from the activity of human.Which is the most everlasting and deepgoing.The heavy metal pollution of soil is harmful to Human settlement the health of the residents.Therefore,the feature analysis and risk evaluate of the pollution to soil heavy mental can intuitively reflect the influence of urbanization on soil environmental quality.Taking the YunLong Demonstration Area of ZhuZhou as the research object.Through research many literature and take some samples in the specified area.Meanwhile,combing with correlative soil datas to carry out the risk assessment of heavy metals in soil.It mainly includes:a)Summarizing risk assessment of heavy metals in soil in China and abroad,analying its development trend to determine the risk assessment methods of heavy metals in YunLong demonstration area;b)Implementing soil survey and sampling work in YunLong demonstation area,analying its horizontal and vertical pollution characteristics:c)The risk assessment of five heavy metals in As,Pb,Cu,Zn and Cd in the study area is carried out by single factor index method-the Nemero index method,cumulative index method and potential ecological hazard index method.The result shows that :1)The cotents of As,Pb,Cu and Zn are in the non-polluted level in the study area,but the individual samples of As is above the national secondary quality standard and the Cd have a seriously overproof problem,whose over-standard rate run up to thirty percent.2)WuXing village and YunFeng lake community have a worse soil heavy mental pollution`s phenomenon than other ares,and the Cd is quitely difference between the soil of 0-20 cm ftom 20-40 cm.The study shows that Cd in the study area is mainly come from external factors;3)The soil environmental quality in the study area is within the acceptable range,but it has been polluted by the heavy metal Cd element,and there may be lightly polluted by As,Pb and Cu elements,and the pollution of the Zn elements is almost not affected in the study area.The study indicates that the heavy metal Cd element in the YunLong area may enter into the soil by the atmosphere settlement and agricultual activities and industrial pollution etc.4)Only combine with single factor index method,the Nemero index method,cumulative index method and potential ecological hazard index method to assess the soil heavy method,can roundly respond the soil heavy mental pollution's level.