Urban soil pollution degree detection method

Abstract

The invention discloses an urban soil pollution degree detection method, particularly relates to the technical field of soil detection, and comprises a sampling area division stage, a sampling stage, a soil pollutant content analysis stage and a data processing stage. The sampling area division stage is used for performing detailed area division according to different use purposes of local soil, performing soil sampling by adopting a snakelike point distribution sampling method, and detecting types and corresponding contents of pollutants in the soil by adopting physical and chemical means; the soil pollution index and the comprehensive pollution degree are calculated according to the detected data, the pollution degree is divided into five levels, and finally the urban soil pollution degree is obtained.By detecting the content of the pollutants in the soil and calculating and dividing the soil pollution index, the urban soil pollution degree can be known more visually, and the urban soil pollution degree can be obtained more accurately. And the environmental awareness of people is improved.

Description

Technical Field

[0001] This invention relates to the field of soil testing technology, and more specifically, to a method for detecting the degree of soil pollution in urban areas. Background Technology

[0002] Existing methods for detecting urban soil pollution levels include the following stages: determining the sampling area, developing the sampling method, detecting pollutants in the soil, and data analysis. Specific advantages include: the large-spacing, uniformly distributed sampling method used in existing technologies solves the problem of sampling difficulties caused by excessively large testing areas; the sampling method is simple and easy to implement, does not cause large-scale damage to the land itself, is suitable for open areas, and the test results are relatively accurate and can be used as a reference; existing technologies comprehensively analyze the degree of soil pollution from two aspects: heavy metal content and pesticide residue content, ensuring the reliability of the test results.

[0003] However, the above-mentioned technologies still have shortcomings, specifically as follows: Existing methods for detecting urban soil pollution levels, which employ large-spacing, uniformly distributed sampling, are prone to overlooking areas with potential pollution risks. The sample size is limited, and the results obtained from these sampling methods cannot be used as the final data for the entire city's soil pollution detection. Therefore, the applicable sampling range is relatively small, making large-scale promotion impossible. Sampling points in these methods are primarily located around factories, underground pipelines, and sewage outlets, making them unsuitable for large-scale farmland and green space construction sites. The detected data lacks universality and cannot be used as the basis for the entire city's soil detection. Among the three evaluation indicators, the engineering properties of soil are easily affected by the external environment, impacting the accuracy of the experimental results. Regarding the indicator of the corrosiveness of contaminated soil to building materials, the soil corrosion test is conducted under ideal conditions; when the external environment changes, the experimental results cannot be used as final data. Summary of the Invention

[0004] To overcome the aforementioned deficiencies of existing methods, this invention provides a method for detecting the degree of urban soil pollution. Based on the different uses of urban soil, the urban soil is divided into five regions. Sampling is conducted in each region to comprehensively detect various organic and inorganic pollutants, as well as harmful and beneficial microorganisms. The content of organic and inorganic pollutants and the proportion of harmful microorganisms are measured and calculated to determine the degree of soil pollution in different regions, thereby solving the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] In a preferred embodiment, the specific steps for obtaining five different sampling regions during the sampling region division stage are as follows:

[0007] 001. In this embodiment, the sampling area is divided according to different land use purposes, specifically into residential areas, agricultural areas, industrial areas, transportation areas, and vegetation green areas.

[0008] In a preferred embodiment, soil sampling is performed by dividing the sampling area into regions to obtain soil samples from different regions.

[0009] The data processing procedure in this embodiment includes the following steps:

[0010] 001. A serpentine sampling method is adopted based on the areas divided in the sampling area division stage;

[0011] 002. Surface sediment was collected from soil at a depth of 0-10cm. Each sampling point was sampled 5 times in parallel. The samples were stored in a vehicle refrigerator at 4 degrees Celsius, freeze-dried, ground and passed through a 100-mesh sieve, and then sealed for storage.

[0012] 003. After freeze-drying the precipitate, grind it to remove impurities such as plants and stones. Take one-quarter of the sample as an experimental sample, pass it through a 200-mesh sieve, and put it into a polyethylene bottle for later use.

[0013] In a preferred embodiment, the soil pollutant content analysis stage involves sending soil samples obtained during the sampling stage to the laboratory for testing and recording the soil pollutant content data.

[0014] The specific steps are as follows:

[0015] 001: Spectrophotometry is used to measure the types and contents of heavy metals in soil;

[0016] 002. Gas chromatography is used to determine the amount of organic pollution in soil;

[0017] 003. The MPN method is used to determine the count of microorganisms in soil.

[0018] In a preferred embodiment, the comprehensive pollution index and the degree of soil pollution are calculated by using the data on the content of pollutants in the sampled soil obtained through the data processing stage in conjunction with the soil pollutant content analysis stage.

[0019] The algorithm for determining this during the data processing stage in this embodiment is as follows:

[0020] 001. Based on the individual pollutant indices in the Nemerow pollution index. Calculate the pollution index of heavy metal and organic pollutants in each soil sample according to the formula. Calculate the total pollution index of heavy metals and organic pollutants in the soil of this region. T1, T2, T3, T4, and T5 are the total pollution indices of heavy metal pollution and organic pollution in five regions.

[0021] 002. Use the MPN counting method to count the microorganisms in the soil and calculate the ratio G of harmful microorganisms to the total number of microorganisms in the soil;

[0022] 003. Based on the above steps, the comprehensive pollution index P of soil in different regions is obtained. 区 = kTi + (1-k)G; where the value of k is specifically defined according to the different land use purposes in different regions;

[0023] 004. The degree of soil pollution in cities, P = αP 区1 +βP 区2 +δP 区3 +εP 区4 +φP 区5 P 区1 To P 区5 The comprehensive pollution index is defined for the five regions, where α, β, δ, ε, and φ represent the proportion of each region's area to the total area of ​​the city.

[0024] 005. The degree of urban soil pollution, P, is divided into 5 levels. The calculated value of urban soil pollution, P, is compared with the classified soil pollution level values ​​to obtain the final measured degree of soil pollution.

[0025] The technical effects and advantages of this invention are as follows:

[0026] This invention assesses the degree of soil pollution from three aspects: heavy metal content, organic matter content, and harmful microorganism content. It also divides cities into regions, effectively solving the problem of inaccurate experimental results caused by uneven sampling. By calculating according to different weights, the data results are more reliable. Attached Figure Description

[0027] Figure 1 This is a block diagram of the method structure of the present invention.

[0028] Figure 2 This is a flowchart of the method of the present invention. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Example 1

[0031] This embodiment provides, for example Figure 1 This paper describes a method for detecting urban soil pollution levels, comprising a sampling area division stage, a sampling stage, a soil pollutant content analysis stage, and a data processing stage. The sampling area division stage involves detailed regional division based on different local soil uses, currently divided into five areas: residential area, agricultural area, industrial area, transportation area, and vegetated green area. The sampling stage employs a serpentine sampling method based on the areas defined in the sampling area division stage. This method is suitable for large areas with uneven terrain and uneven soil, ensuring random and uniform sampling. The soil pollutant content analysis stage uses physical and chemical methods to detect the types and corresponding contents of pollutants in the soil. The data processing stage performs corresponding calculations on the data obtained from the soil pollutant content analysis stage, including individual pollutant indices. The total pollution index T is calculated using the following formula: in The total pollution index for residential areas is T1, for agricultural areas it is T2, for industrial areas it is T3, for transportation areas it is T4, and for vegetated green areas it is T5. Microorganisms in the soil are counted, and the ratio G of harmful microorganisms to the total number of microorganisms in the soil is calculated. The comprehensive pollution index P of the soil in a single area is then determined. 区 =kTi+(1-k)G, where the value of k is specifically defined according to the different land use purposes in different areas; calculate the degree of soil pollution in the city P=αP 区1 +βP 区2 +δP 区3 +εP 区4 +φP 区5 , where α, β, The values ​​of δ and φ are determined by the proportion of the soil area contained in each region to the total area of ​​the city.

[0032] The difference between this implementation and existing technologies lies in the sampling area division stage, the soil pollutant content analysis stage, and the data processing stage. Specifically, in the sampling area division stage, urban land is divided into different areas according to different usage types, thus expanding the soil sampling range and increasing its applicability, not being limited to a specific environment. In the soil pollutant content analysis stage, a comprehensive analysis of soil pollutants is conducted, including soil heavy metal pollution indicators, soil organic matter pollution indicators, and soil microbial indicators, not limited to the analysis of the content of a few pollutants. In the data processing stage, the soil pollution index is still calculated, and the comprehensive urban soil pollution index is calculated according to different regional weights to classify the degree of soil pollution. This entire process is not available in existing methods.

[0033] like Figure 2 This embodiment provides a method for detecting the degree of urban soil pollution, which specifically includes the following steps:

[0034] 101. Five different sampling regions were obtained by performing the sampling region division stage.

[0035] In this embodiment, the sampling area is divided according to different land use purposes, specifically into residential areas, agricultural areas, industrial areas, transportation areas, and vegetated green areas.

[0036] 102. Soil sampling was conducted based on the regional classification obtained through the sampling area division stage, resulting in soil samples from different regions.

[0037] The data processing procedure in this embodiment includes the following steps:

[0038] A1. A serpentine sampling method is adopted based on the areas divided in the sampling area division stage;

[0039] A2. Take surface sediment samples from soil at a depth of 0-10cm. Collect samples at each point 5 times in parallel. Store the samples in a vehicle refrigerator at 4 degrees Celsius, freeze-dry, grind them through a 100-mesh sieve, and seal them for storage.

[0040] A3. After freeze-drying the precipitate, grind it to remove impurities such as plants and stones. Take one-quarter of the sample as an experimental sample, pass it through a 200-mesh sieve, and put it into a polyethylene bottle for later use.

[0041] It has the following functions: The sampling stage adopts a serpentine sampling method, which can still be used to sample in large areas with uneven terrain, and the data obtained is highly accurate, ensuring the average in the experimental process. Random sampling and parallel collection of soil at each sampling point ensure the fairness and accuracy of the sampling results. Removing impurities and plants reduces the possibility of external interference in the final analysis results.

[0042] 103. In the soil pollutant content analysis stage, the soil samples obtained in the sampling stage are sent to the laboratory for testing, and the soil pollutant content data are recorded.

[0043] The specific steps are as follows:

[0044] B1: Spectrophotometry is used to measure the types and contents of heavy metals in soil;

[0045] B2. Gas chromatography is used to determine organic pollution in soil;

[0046] B3, the MPN method is used to determine the count of microorganisms in soil;

[0047] Its functions are as follows: to determine the types and contents of pollutants in the soil, obtain corresponding data, and provide data support for the data processing stage.

[0048] 104. The comprehensive pollution index and soil pollution level are calculated from the data on the pollutant content of the sampled soil obtained in the data processing stage in conjunction with the soil pollutant content analysis stage.

[0049] The algorithm for determining this during the data processing stage in this embodiment is as follows:

[0050] C1. Based on the individual pollutant indices in the Nemerow pollution index. Calculate the pollution index of heavy metal and organic pollutants in each soil sample according to the formula. Calculate the total pollution index of heavy metals and organic pollutants in the soil of this region. T1, T2, T3, T4, and T5 are the total pollution indices of heavy metal pollution and organic pollution in five regions.

[0051] C2. Use the MPN counting method to count the microorganisms in the soil and calculate the ratio G of harmful microorganisms to the total number of microorganisms in the soil.

[0052] C3. Based on the above steps, obtain the comprehensive pollution index P of soil in different regions. 区 = kTi + (1-k)G; where the value of k is specifically defined according to the different land use purposes in different regions;

[0053] C4. The degree of soil pollution in the city, P = αP 区1 +βP 区2 +δP 区3 +εP 区4 +φP 区5 P 区1 To P 区5 The comprehensive pollution index is defined for the five regions, where α, β, δ, ε, and φ represent the proportion of each region's area to the total area of ​​the city.

[0054] C5. The degree of urban soil pollution, P, is divided into 5 levels. The calculated value of urban soil pollution, P, is compared with the classified soil pollution level values ​​to obtain the final measured degree of soil pollution.

[0055] Specifically, the data processing module can calculate the comprehensive pollution index and pollution level of the sampled land, making data extraction more accurate, less affected by external factors, and visualizing the soil pollution level for easier land management.

[0056] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for detecting the degree of urban soil pollution, characterized in that: The sampling area division stage, the sampling stage, the soil pollutant content analysis stage, and the data processing stage; the sampling area division stage divides the city into five areas according to different soil utilization purposes, namely, residential area, agricultural area, industrial area, transportation area, and vegetation green area; the sampling stage samples the five areas by using the snake-shaped sampling method; the soil pollutant content analysis stage analyzes the soil pollutants collected in the sampling stage, including heavy metal pollutants, organic pollutants, and harmful microorganisms; and the data processing stage analyzes the pollutant content data obtained in the soil pollutant content analysis stage and calculates the single pollution index T of different areas and the total pollution index P 区 The calculation of the urban soil comprehensive pollution index P and the urban soil pollutant index P is the addition of the total pollution indexes of the areas according to the different weights of the areas, and the urban soil pollution degree is divided into levels according to the comprehensive pollution index, i.e., a total of 1-5 levels.

2. The method for detecting the degree of urban soil pollution according to claim 1, characterized in that: The sampling area division stage, the division steps of different areas are specifically as follows: A1: According to the different use purposes of local soil, detailed regional division is carried out, and at present, five regions are divided, i.e. residential area, agricultural area, industrial area, traffic area and vegetation green area.

3. The method for detecting the degree of urban soil pollution according to claim 1, characterized in that: The data acquisition process in the sampling stage includes the following steps: B1, according to the regions divided in the sampling area division stage, the snake-shaped point distribution sampling method is adopted; B2, the surface sediments are taken, 5 times of parallel sampling are carried out at each sampling point, the vehicle-mounted refrigerator is used for preservation, freeze-drying is carried out, grinding and sieving are carried out, and sealing preservation is carried out; B3, after the sediments are freeze-dried, the plant and stone impurities are removed by grinding, one fourth of the experimental sample is taken, sieving is carried out, and the polyethylene bottle is used for storage.

4. The method for detecting the degree of urban soil pollution according to claim 1, characterized in that: The analysis process in the soil pollutant content analysis stage is specifically as follows: C1: Spectrophotometry is used to measure the types and contents of heavy metals in soil; C2, gas chromatography is used to measure the determination of organic matter pollution in soil; C3, MPN method is used to determine the count of microorganisms in soil.

5. The method for detecting the degree of urban soil pollution according to claim 1, characterized in that: The specific steps of the data processing stage are as follows: D1. The individual pollutant index according to the Nemeroi pollution index The pollution index of heavy metal and organic pollutants in each soil sample was calculated according to the formula The total pollution index of heavy metal and organic pollutants in the soil of the area was calculated; D2, the MPN counting method is used to complete the count of microorganisms in soil, and the ratio G of the number of harmful microorganisms to the total number of microorganisms in soil is calculated; D3. The comprehensive pollution index P of the soil in different regions is obtained according to the above steps 区 = kTi + (1 - k)G; D4, the degree of soil pollution P of the city = αP 区1 + βP 区2 + δP 区3 + εP 区4 + φP 区5 ; D5, the urban soil pollution degree P is divided into five levels, the calculated urban soil pollution degree value P is compared with the divided soil pollution degree value, and the final determined soil pollution degree is obtained.

6. The method for detecting the degree of urban soil pollution according to claims 1-5, characterized in that: The specific steps are as follows: E1, five different sampling areas are obtained by operating through the sampling area division stage; E2, soil sampling is carried out through the region classification obtained through the sampling area division stage, and soil samples of different regions are obtained. E3, the soil samples obtained through the sampling stage are sent to the laboratory for detection in the soil pollutant content analysis stage, and the soil pollutant content data are recorded; E4, the comprehensive pollution index and the soil pollution degree are calculated through the data processing stage and the soil pollutant content data obtained through the soil pollutant content analysis stage.

7. The urban soil pollution degree detection method according to claim 6, wherein: The data processing stage processes and calculates the data obtained by the soil pollutant content analysis stage, wherein the single pollutant index The total pollution index T is calculated by the formula Wherein The total pollution index of the residential area is T1, the total pollution index of the agricultural area is T2, the total pollution index of the industrial area is T3, the total pollution index of the traffic area is T4, and the total pollution index of the vegetation green area is T5. The number of harmful microorganisms in the soil is counted, and the ratio of the number of harmful microorganisms to the number of microorganisms in the soil is calculated as G. The comprehensive pollution index P of the soil in a single area is calculated 区 = kTi + (1-k)G, wherein the value of k is specified according to the different purposes of land use in different areas; the soil pollution degree P of the city is calculated as αP 区1 + βP 区2 + δP 区3 + εP 区4 + φP 区5 , wherein the values of α, β, δ, and φ are determined by the proportion of the soil area in each area to the total area of the city. The soil pollution degree is divided into 5 levels: level 1 (pollution comprehensive index P≤0.7) is the safety level, the soil is not polluted; level 2 (0.7 to 1) is the warning level, the soil is still clean; level 3 (1 to 2) is the light pollution, crops and fruit trees begin to be polluted; level 4 (2 to 3) is the medium pollution, crops or fruit trees are moderately polluted; and level 5 (P>3) is the heavy pollution, crops or fruit trees are severely polluted. The data processing module can calculate the comprehensive pollution index and the pollution degree of the sampled land, the data extraction is more accurate, the influence degree of the external environment is smaller, the soil pollution degree is visualized, and land management is facilitated.

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