Research On The Arrangement Technology Of Soil Environmental Background Area And Background Point

The soil environmental background value refers to the content of a certain chemical element or a certain compound in the soil,which is not or less affected by human activities.The background value of soil environment is the basic data of soil environmental science and the basis for evaluating soil environmental quality.The scientific and reasonable arrangement of soil environmental background points is an important condition for obtaining soil environmental background values.There has put forward many technical specifications for soil environmental monitoring in China,and the content mentions the requirements for soil environmental background point sampling,but it is not a standard based on the soil environmental background point layout,which lacks systematicity and operability.Therefore,it is very necessary to carry out the research on soil environmental background point placement technology.In this paper,taking granite brown soil in Fushun City as an example,it combined Arc GIS software with field sampling and indoor analysis to study the technical methods for demarcating the soil environmental background area and the arrangement of the soil environmental background points.By collecting 45 soil samples and comparing them with the background values of granite brown soil in Liaoning Province,the rationality of the arrangement of the soil environmental background areas and background points was verified,in order to provide technical support for the investigation of the soil environmental background values.The main research conclusions were as follows:1.The specific procedure of soil environmental background point layout was as follows:(1)Using the soil genus map to identify the distribution area of granite brown soil.(2)The distribution map of urban and rural residential land,the distribution map of industrial and mining enterprises,the distribution map of traffic roads,and the distribution map of water areas and water conservancy facilities were successively superimposed to identify environmental interference sources in the granite brown soil distribution area.According to the influence range of each environmental interference source,each environmental interference area was generated;each environmental interference area was removed,and the soil environment background area was obtained.(3)According to the size of each background area,each soil environment background area was divided into 3～5 units,and a soil environment background point was placed in the center of the unit.2.The content distribution range of Cd element in granite brown soil in Fushun City was 0.18～0.24 mg/kg,Pb was 20.56～24.46 mg/kg,Cr was 23.36～25.87 mg/kg,Cu was 11.29～13.56 mg/kg,Zn was 56.63～62.05 mg/kg,Ni was 14.81～17.02 mg/kg,Mn was 395.88～468.55 mg/kg,Co was 6.44～7.36 mg/kg,and V was 44.97～48.78 mg/kg.3.The content of various elements in the granite brown soil in Fushun city was relatively low,and the soil environmental quality maintained the level of natural background.Compared with the background value of granite brown soil in Liaoning Province,the contents of Cd,Pb,Cr,Cu,Zn,Ni,Mn,Co and V were all within the 95% confidence interval of the background value of granite brown soil in Liaoning Province in this study,which conformed to the background level.In summary,this paper proposed that the method of setting soil environmental background area and soil environmental background point was feasible.