Nondestructive testing method and system for heavy metal pollution of camellia oleifera

Abstract

The invention relates to the technical field of soil remediation, in particular to a nondestructive testing method and system for heavy metal pollution of camellia oleifera abel. The method comprises the steps that sample spectrograms of a camellia oleifera abel garden every day are obtained, and a plurality of soil improvement days are selected from the sample spectrograms; obtaining the content of each heavy metal in the sample every day according to the sample spectrogram every day; acquiring the characteristic distance of each soil improvement day according to the content of each heavy metal in the sample every day; according to the characteristic distance between the adjacent soil improvement days, the primary pH value reduction value of the soil improvement days is obtained; according to the characteristic distance between every two adjacent soil improvement days, the primary pH value reduction value of the soil improvement days is corrected, and the pH value reduction value of the soil improvement days is obtained. By detecting the content of various heavy metals in the camellia oleifera garden soil and combining the heavy metal absorption rate of the camellia oleifera trees, the heavy metals in the soil are gradually solidified, and normal growth of the camellia oleifera trees is prevented from being affected when the soil quality is improved.

Description

Technical Field

[0001] The invention relates to the technical field of soil remediation, and in particular to a nondestructive detection method and system for heavy metal pollution in oil tea trees. Background Art

[0002] Heavy metals in the soil of tea gardens will hinder the root development of tea trees in the gardens and inhibit their photosynthesis. At the same time, heavy metals in the soil of tea gardens will also inhibit the activity of beneficial microorganisms in the soil, thereby endangering the growth and development of tea trees. Therefore, it is necessary to detect the heavy metal content in the soil of tea gardens and improve the soil quality of tea gardens. However, the traditional method of improving soil quality by spreading acidifiers does not consider the impact of improving soil quality on tea trees in the gardens. When the pH value of the soil suddenly changes drastically, it will damage the root system of the tea tree and affect the absorption of nutrients by the tea tree. At the same time, it will also change the microbial community in the soil, causing the activity of beneficial microorganisms in the soil to decrease, thereby endangering the growth and health of the tea tree; that is, the traditional method of improving soil quality will endanger the growth and health of the tea tree. Summary of the invention

[0003] The invention provides a nondestructive detection method and system for heavy metal pollution of oil tea trees, so as to solve the existing problem that the traditional method for improving soil quality will harm the growth and health of oil tea trees.

[0004] The present invention discloses a nondestructive detection method and system for heavy metal pollution in tea oil trees using the following technical solutions: One embodiment of the present invention provides a nondestructive detection method for heavy metal pollution in oil tea trees, the method comprising the following steps: Obtain the daily sample spectra of the oil tea garden and select several soil improvement days from them; According to the daily sample spectra, the content of each heavy metal in the daily samples is obtained; According to the content of each heavy metal in the daily sample and the content of each heavy metal in all previous samples, the daily sample space is constructed to obtain several clusters in the daily sample space; according to the several clusters in the sample space of each soil improvement day, the characteristic distance of each soil improvement day is obtained; according to the characteristic distances of adjacent soil improvement days, the primary pH value reduction value of the soil improvement day is obtained; According to the daily characteristic distance between adjacent soil improvement days, the change fitting straight line of the soil improvement day is obtained; according to the change fitting straight line of the soil improvement day, the primary pH value reduction value of the soil improvement day is corrected to obtain the pH value reduction value of the soil improvement day.

[0005] Preferably, the method of obtaining the sample spectra of the oil tea garden every day and selecting several soil improvement days therefrom includes the following specific methods: For Day, randomly selected in the tea garden sampling points, and samples were collected at each sampling point in the oil tea garden. The collected soil was placed in a fume hood to air dry, and the air-dried soil was ground with a mortar to obtain soil powder. The purpose sieve filters the soil powder to obtain the The samples to be tested on the day are detected by spectrometer. The samples to be tested on the day are obtained Sample spectra of the day; , as well as They are the preset number of sampling points, soil collection quality, and sieve specifications; Preset a soil improvement cycle , on the first day and every other day after the first day The date of the day is recorded as the soil improvement day.

[0006] Preferably, the specific method of obtaining the content of each heavy metal in the daily sample according to the daily sample spectrum is as follows: For The sample of the day heavy metal content; obtain the The characteristic band of heavy metals and set the The content limit of the heavy metals in the oil tea garden soil The spectrum when the heavy metal content is at the content limit is recorded as the reference spectrum. The curve segment of the characteristic wave band of the heavy metal is recorded as the reference curve segment; In the sample spectrum of the day, The curve segment of the characteristic wave band of the heavy metal is combined with the reference curve segment and the content limit to obtain the The sample of the day Heavy metal content.

[0007] Preferably, the obtaining The sample of the day The specific calculation formula for the content of heavy metals is as follows: In the formula, Indicates The sample of the day Heavy metal content; Indicates Content limits of various heavy metals; Indicates In the sample spectrum of the day, The definite integral of the curve segment of the characteristic band of the heavy metal; represents the definite integral of the reference curve segment; represents the hyperbolic tangent function.

[0008] Preferably, the method of constructing a daily sample space according to the content of each heavy metal in the daily sample and the content of each heavy metal in all previous samples, and obtaining several clusters in the daily sample space includes the following specific methods: Construct an N-dimensional sample space, where N is the number of heavy metal types; Day, will Heaven and Earth The samples before the day are recorded as target samples. According to the content of each heavy metal in each target sample, all target samples are placed in the sample space, and each target sample is used as a data point in the sample space to obtain the first Sample space of day; Using DBSCAN clustering algorithm The data points in the sample space of the first day are clustered, and the distance metric is the Euclidean distance between the data points. Several clusters in the sample space of the day.

[0009] Preferably, the method of obtaining the characteristic distance of each soil improvement day according to the plurality of clusters in the sample space of each soil improvement day includes: For Soil Improvement Day The sample space of the soil improvement day contains The cluster of data points corresponding to the soil improvement day is recorded as The target clusters in the sample space of the soil improvement day are The distance between the target cluster center and the origin of the sample space in the sample space of the soil improvement day is recorded as Characteristic distance of soil improvement days.

[0010] Preferably, the primary pH value reduction value of the soil improvement day is obtained according to the characteristic distance between adjacent soil improvement days, and the specific calculation formula included is: In the formula, Indicates Primary pH reduction per soil improvement day; Indicates pH reduction value per soil improvement day; Indicates characteristic distance of soil improvement days; Indicates characteristic distance of soil improvement days; Indicates characteristic distance of soil improvement days; Indicates characteristic distance of soil improvement days; Indicates The differences in characteristic distances of all adjacent soil improvement days before the soil improvement day are traversed, and the maximum value function is taken.

[0011] Preferably, the method of obtaining the variation fitting straight line of the soil improvement day according to the daily characteristic distance between adjacent soil improvement days includes: For any soil improvement day, the date between the last soil improvement day and the soil improvement day is recorded as a change day, and the characteristic distance of each change day is obtained; A rectangular coordinate system is constructed with the date as the horizontal axis and the characteristic distance of the change day as the vertical axis. Each change day is taken as a coordinate point and placed in the rectangular coordinate system to obtain a scatter plot of the changes in the soil improvement day. The scatter plot of the changes in the soil improvement day is fitted with a straight line using the least squares method to obtain a fitted straight line of the changes in the soil improvement day.

[0012] Preferably, the fitting straight line according to the change of the soil improvement day, correcting the primary pH value reduction value on the soil improvement day, and obtaining the pH value reduction value on the soil improvement day includes the following specific methods: For any soil improvement day, the primary pH value reduction value on the soil improvement day is corrected according to the root mean square error of the change fitting line on the soil improvement day and the slope of the change fitting line on the soil improvement day to obtain the pH value reduction value on the soil improvement day. The specific calculation formula is: In the formula, represents the pH reduction value on the soil improvement day; represents the decrease in primary pH value on the day of soil improvement; The root mean square error of the fitted straight line representing the variation of the soil improvement day; The slope of the fitted straight line representing the change of the soil improvement day; Represents the sigmoid function.

[0013] Another embodiment of the present invention provides a nondestructive detection system for heavy metal pollution in oil tea trees, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any one of the above-mentioned methods for nondestructive detection of heavy metal pollution in oil tea trees when executing the computer program.

[0014] The beneficial effect of the technical solution of the present invention is as follows: the present application obtains the sample spectra of the oil tea garden every day, and selects several soil improvement days therefrom; according to the sample spectra of each day, obtains the content of each heavy metal in the sample of each day; according to the content of each heavy metal in the sample of each day, obtains the characteristic distance of each soil improvement day, the characteristic distance of the soil improvement day represents the content of various heavy metals in the sample of the soil improvement day, the larger the characteristic distance, the greater the content of various heavy metals in the corresponding sample, when the difference in characteristic distance between adjacent soil improvement days is greater, it means that the oil tea tree absorbs more heavy metals from the soil, and the more heavy metals that are not solidified in the soil, so it is more necessary to lower the pH value of the soil to solidify the heavy metals in the soil to prevent the heavy metals from being absorbed by the oil tea tree.

[0015] According to the daily characteristic distance between adjacent soil improvement days, the change fitting straight line of the soil improvement day is obtained. The smaller the slope of the change fitting straight line of the soil improvement day, the more heavy metals the oil tea tree absorbs during this period, which will harm the health of the oil tea tree. Therefore, the pH value should be reduced more. The larger the root mean square error of the change fitting straight line of the soil improvement day, the greater the difference in the amount of heavy metals absorbed by the oil tea tree in the soil every day, which means that the oil tea tree has been harmed by the heavy metals in the soil and cannot absorb energy from the soil stably. Therefore, the pH value should be reduced more. According to the change fitting straight line of the soil improvement day, the primary pH value reduction value of the soil improvement day is corrected to obtain the pH value reduction value of the soil improvement day, so as to gradually solidify the heavy metals in the soil and avoid affecting the normal growth of the oil tea tree when improving the soil quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 The present invention is a flowchart of the steps of a nondestructive detection method for heavy metal pollution in oil tea trees. DETAILED DESCRIPTION

[0018] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of a method and system for nondestructive detection of heavy metal pollution in oil tea trees proposed by the present invention, its specific implementation method, structure, features and effects, in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0019] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0020] The specific scheme of the nondestructive detection method and system for heavy metal pollution in oil tea trees provided by the present invention is described in detail below with reference to the accompanying drawings.

[0021] See also Figure 1 , which shows a flowchart of a method for nondestructive detection of heavy metal pollution in oil tea trees provided by an embodiment of the present invention, the method comprising the following steps: Step S001: Obtain the sample spectra of the oil tea garden every day, and select several soil improvement days therefrom.

[0022] It should be noted that the ultimate goal of this embodiment is to prevent the oil tea tree from absorbing excessive heavy metals during its growth process, which would lead to shortened root length and reduced root and leaf weight, seriously endangering the health of the oil tea tree. At the same time, heavy metals will also affect the photosynthesis of the oil tea tree, thereby hindering the growth and development of the oil tea tree and reducing the environmental adaptability of the oil tea tree. Therefore, this embodiment proposes a nondestructive detection method for heavy metal contamination of oil tea trees, which can gradually improve the degree of heavy metal contamination in the oil tea garden while detecting the heavy metal content in the soil of the oil tea garden.

[0023] It should be further explained that an acidic environment can promote the conversion of heavy metals into insoluble precipitates, thereby reducing the absorption of heavy metals by tea trees in tea gardens. Acidic environments can increase the activity of antioxidant enzymes in plants and reduce the oxidative stress caused by heavy metals. At the same time, acidified soil can improve the living environment of microbial communities in the soil, help the conversion and fixation of heavy metals, and further reduce the harm of heavy metals. However, in the process of improving the soil quality of tea gardens, if the pH value of the soil is suddenly changed significantly, it will damage the root system of tea trees and affect the absorption of nutrients by tea trees. It will also change the microbial community in the soil, reduce the activity of beneficial microorganisms in the soil, and then endanger the growth and health of tea trees. Therefore, improving soil quality by lowering the pH value of the soil should be done slowly to ensure the healthy growth of tea trees.

[0024] Specifically, for Day, randomly selected in the tea garden sampling points, and samples were collected at each sampling point in the oil tea garden. The collected soil was placed in a fume hood to air dry, and the air-dried soil was ground with a mortar to obtain soil powder. The purpose sieve filters the soil powder to obtain the The samples to be tested on the day are detected by spectrometer. The samples to be tested on the day are obtained The sample spectra of the day are obtained, and the sample spectra of each day are obtained similarly; , as well as The preset sampling point quantity, soil collection quality and sieve specifications are respectively , as well as The specific value of can be set according to the actual situation. This embodiment does not make a hard requirement. , , The specific process of collecting the spectrum through the spectrometer is a well-known prior art, so it will not be described in detail in this embodiment.

[0025] Furthermore, an initial pH reduction value is preset and soil improvement cycle , and The specific value of can be set according to the actual situation. This embodiment does not make a hard requirement. , Describe; starting from the first day, after obtaining the sample spectrum of the first day, the pH value of the oil tea garden soil was reduced by spreading acidic substances on the oil tea garden soil , and every After obtaining the spectrum graph, the pH value of the oil tea garden soil is lowered according to the spectrum graph collected before, so as to gradually improve the soil quality of the oil tea garden, and the date on which the pH value of the oil tea garden soil is lowered is recorded as the soil improvement day; the acidic substances spread on the oil tea garden soil include: ferrous sulfate, aluminum sulfate, acetic acid, etc., which are not rigidly required in this embodiment and can be set according to the actual situation; the subsequent content is the processing process of obtaining the pH reduction value on each soil improvement day.

[0026] It should be noted that by acidifying the soil contaminated by heavy metals, the binding rate of heavy metals in the soil with minerals or organic matter in the soil can be increased, making the heavy metals in the soil easier to fix, thereby reducing the absorption of heavy metals by the tea trees in the tea garden and reducing the toxicity of heavy metals in the soil to plants.

[0027] At this point, the sample spectra for each day are obtained.

[0028] Step S002: According to the daily sample spectra, the content of each heavy metal in the daily samples is obtained.

[0029] It should be noted that this embodiment is a nondestructive detection method for heavy metal pollution in oil tea trees. Specifically, it is used to improve the quality of oil tea garden soil by detecting the heavy metal content in the soil. Therefore, it is necessary to first obtain the content of various heavy metals in daily samples. The heavy metals in the sample will absorb light in a specific band. Different heavy metals absorb different light bands. Therefore, the content of heavy metals in the sample can be obtained based on this.

[0030] Preferably, in a specific embodiment of the present invention, for The sample of the day heavy metal content; obtain the The characteristic band of heavy metals and set the The content limit of heavy metals The content limit of each heavy metal can be set according to actual requirements. In this embodiment, it is set according to the requirements of the "Agricultural Land Soil Environmental Quality Standard (Third Draft for Comments)"; the content of the first heavy metal in the oil tea garden soil is obtained. The spectrum when the heavy metal content is at the content limit is recorded as the reference spectrum. The curve segment of the characteristic wave band of the heavy metal is recorded as the reference curve segment; In the sample spectrum of the day, The curve segment of the characteristic wave band of the heavy metal is combined with the reference curve segment and the content limit to obtain the In the sample of the day The specific calculation formula for the content of heavy metals is: In the formula, Indicates In the sample of the day Heavy metal content; Indicates Content limits of various heavy metals; Indicates In the sample spectrum of the day, The definite integral of the curve segment of the characteristic band of the heavy metal; represents the definite integral of the reference curve segment; represents the hyperbolic tangent function, which is used to map the calculation result to the range of (-1, 1) in this embodiment.

[0031] It needs to be further explained that The characteristic band of heavy metals represents the The specific wavelength band of light absorbed by the heavy metal in the sample; the reference curve segment indicates that when the When the content of a heavy metal reaches the limit, The spectral curve under the characteristic band of the heavy metal; In the sample spectrum of the day, The larger the area enclosed by the curve segment of the characteristic waveband of the heavy metal and the horizontal axis (the definite integral of the curve segment) is than the area enclosed by the reference curve segment and the horizontal axis (the definite integral of the curve segment), the greater the area enclosed by the reference curve segment and the horizontal axis (the definite integral of the curve segment). In the sample spectrum of the day, The higher the heavy metal content, the The content limit of various heavy metals is determined to obtain the content of various heavy metals in the sample.

[0032] At this point, the content of each heavy metal in the samples for each day was obtained.

[0033] Step S003: According to the content of each heavy metal in each daily sample and the content of each heavy metal in all previous samples, a daily sample space is constructed to obtain several clusters in the daily sample space; according to the several clusters in the sample space of each soil improvement day, a characteristic distance of each soil improvement day is obtained; according to the characteristic distances of adjacent soil improvement days, a primary pH reduction value of the soil improvement day is obtained.

[0034] It should be noted that, usually, soil is always contaminated by a variety of heavy metals, and different heavy metals have different effects on plants growing in the soil. For example, microbial biomass carbon and nitrogen in soil contaminated by heavy metals copper, zinc, chromium, and lead are significantly negatively correlated with the content of heavy metals copper, zinc, chromium, and lead, while heavy metal chromium can seriously affect the bacterial community structure in the soil; therefore, this embodiment clusters the samples by the content of each heavy metal in the samples of each day to reflect the content of various heavy metals in different samples.

[0035] Preferably, in a specific embodiment of the present invention, an N-dimensional sample space is constructed, wherein N is the number of heavy metal species; Day, will Heaven and Earth The samples before the day are recorded as target samples. According to the content of each heavy metal in each target sample, all target samples are placed in the sample space, and each target sample is used as a data point in the sample space to obtain the first Sample space of day; Furthermore, using the DBSCAN clustering algorithm, The data points in the sample space of the first day are clustered, and the distance metric is the Euclidean distance between the data points. Since the DBSCAN clustering algorithm is a well-known prior art, it will not be described in detail in this embodiment.

[0036] Similarly, several clusters in the sample space of each day are obtained.

[0037] It should be noted that the samples in the cluster have similar metal contents; the acidic environment will increase the degree of binding between heavy metal elements and organic matter in the soil. Organic matter, as a soluble organic mixture with rich functional groups and complex structure, has a huge impact on the changes in the form of heavy metals in the soil. It can provide adsorption sites for heavy metals, which is beneficial to the solidification of heavy metals in the soil, thereby reducing the absorption of heavy metals by plants and further weakening the impact of heavy metals on tea trees in tea gardens.

[0038] It needs to be further explained that, when the soil is acidified to solidify the heavy metals in the soil, the content of heavy metals in the soil is not reduced, but the heavy metals in the soil are prevented from being absorbed by the tea oil tree. When the content of heavy metals in the soil is reduced, it means that the heavy metals in the soil are absorbed by the tea oil tree. Therefore, when the content of heavy metals in the soil is reduced after the soil is acidified, it means that there are unsolidified heavy metals in the soil that are absorbed by the tea oil tree, and the heavy metals in the soil need to be further solidified.

[0039] Preferably, in a specific embodiment of the present invention, for Soil Improvement Day The sample space of the soil improvement day contains The cluster of data points corresponding to the soil improvement day is recorded as The target clusters in the sample space of the soil improvement day are The distance between the target cluster center and the origin of the sample space in the sample space of the soil improvement day is recorded as characteristic distance of soil improvement days; Furthermore, for the Soil improvement day, according to and The characteristic distance of the soil improvement day, combined with the The pH value decreased by the soil improvement day, and the The specific calculation formula for the reduction of primary pH value on soil improvement day is: In the formula, Indicates Primary pH reduction per soil improvement day; Indicates pH reduction value per soil improvement day; Indicates characteristic distance of soil improvement days; Indicates characteristic distance of soil improvement days; Indicates characteristic distance of soil improvement days; Indicates characteristic distance of soil improvement days; Indicates The differences in characteristic distances of all adjacent soil improvement days before the soil improvement day are traversed, and the maximum value function is taken.

[0040] It should be noted that the characteristic distance of the soil improvement day represents the content of various heavy metals in the samples on the soil improvement day. The larger the characteristic distance, the greater the content of various heavy metals in the corresponding samples. The larger the value is, the more heavy metals the tea oil tree absorbs from the soil, and the more heavy metals that are not solidified in the soil. Therefore, it is more necessary to lower the pH value of the soil to solidify the heavy metals in the soil and prevent the heavy metals from being absorbed by the tea oil tree.

[0041] Thus, the primary pH reduction value on each soil improvement day was obtained.

[0042] Step S004: obtaining a fitted straight line of change on the soil improvement day based on the daily characteristic distances between adjacent soil improvement days; correcting the primary pH value reduction value on the soil improvement day based on the fitted straight line of change on the soil improvement day to obtain the pH value reduction value on the soil improvement day.

[0043] It should be noted that in the process of improving the soil quality of tea oil gardens, if the pH value of the soil is suddenly changed drastically, it will damage the root system of the tea oil tree and affect the absorption of nutrients by the tea oil tree. The microbial community in the soil will also change accordingly, causing the activity of beneficial microorganisms in the soil to decrease, thereby endangering the growth and health of the tea oil tree. Also, due to the differences in the absorption of heavy metals in the soil due to the growth of the plants themselves, in order to avoid excessive adjustments to the soil pH value, which will have an adverse effect on plant growth, the pH value adjustment should be corrected.

[0044] Preferably, in a specific embodiment of the present invention, for any soil improvement day, the date between the last soil improvement day of the soil improvement day and the soil improvement day is recorded as a change day (the change day includes the soil improvement day and the last soil improvement day of the soil improvement day), and the characteristic distance of each change day is obtained; since the process of obtaining the characteristic distance of the change day is the same as that of obtaining the characteristic distance of the soil improvement day, it will not be repeated in this embodiment; Furthermore, a rectangular coordinate system is constructed with the date as the horizontal axis and the characteristic distance of the change day as the vertical axis, and each change day is taken as a coordinate point and placed in the rectangular coordinate system to obtain a scatter plot of the changes on the soil improvement day; the scatter plot of the changes on the soil improvement day is fitted with a straight line using the least squares method to obtain a fitted straight line of the changes on the soil improvement day; since the least squares method is a well-known prior art, it will not be described in detail in this embodiment.

[0045] It should be further explained that the fitting straight line of the change on the soil improvement day represents the change in the content of various heavy metals in the soil every day between two adjacent soil improvement days. The smaller the slope of the fitting straight line, the more heavy metals the oil tea tree absorbs during this period, which will harm the health of the oil tea tree. The greater the reduction in its pH value, the more it should be used as a basis for obtaining the pH reduction value on the soil improvement day.

[0046] Preferably, in a specific embodiment of the present invention, for any soil improvement day, the primary pH value reduction value on the soil improvement day is corrected according to the root mean square error of the change fitting line on the soil improvement day and the slope of the change fitting line on the soil improvement day to obtain the pH value reduction value on the soil improvement day, and the specific calculation formula is: In the formula, represents the pH reduction value on the soil improvement day; represents the decrease in primary pH value on the day of soil improvement; The root mean square error of the fitted straight line representing the variation of the soil improvement day; The slope of the fitted straight line representing the change of the soil improvement day; represents a sigmoid function, which is used for normalization processing in this embodiment.

[0047] It should be further explained that the larger the root mean square error of the fitted straight line of soil improvement day changes, the greater the difference in the amount of heavy metals absorbed by the tea tree in the soil every day, which means that the tea tree has been harmed by the heavy metals in the soil and cannot absorb energy from the soil stably. Therefore, the larger the root mean square error of the fitted straight line of soil improvement day changes, the greater the pH value should be reduced; and because the smaller the slope of the fitted straight line of soil improvement day changes, the greater the pH value should be reduced; therefore The larger the value, the greater the pH reduction should be.

[0048] Furthermore, a soil improvement termination threshold is preset , The specific value of can be set according to the actual situation. This embodiment does not make a hard requirement. Narrate; when you get to the Within the soil improvement days, the improvement of the oil tea garden soil was completed and the heavy metals in the oil tea garden soil were solidified.

[0049] Another embodiment of the present invention provides a nondestructive detection system for heavy metal pollution in oil tea trees, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, a nondestructive detection method for heavy metal pollution in oil tea trees in steps S001 to S004 is implemented.

[0050] 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 principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A nondestructive detection method for heavy metal pollution in oil tea trees, characterized in that: The method comprises the following steps: Obtain the daily sample spectra of the oil tea garden and select several soil improvement days from them; According to the daily sample spectra, the content of each heavy metal in the daily samples is obtained; According to the content of each heavy metal in the daily sample and the content of each heavy metal in all previous samples, the daily sample space is constructed to obtain several clusters in the daily sample space; according to the several clusters in the sample space of each soil improvement day, the characteristic distance of each soil improvement day is obtained; according to the characteristic distances of adjacent soil improvement days, the primary pH value reduction value of the soil improvement day is obtained; According to the daily characteristic distance between adjacent soil improvement days, the change fitting straight line of the soil improvement day is obtained; according to the change fitting straight line of the soil improvement day, the primary pH value reduction value of the soil improvement day is corrected to obtain the pH value reduction value of the soil improvement day.

2. According to claim 1, a nondestructive detection method for heavy metal pollution in oil tea trees is characterized in that: The specific method of obtaining the sample spectrum of the oil tea garden every day and selecting several soil improvement days therefrom includes: For Day, randomly selected in the tea garden sampling points, and samples were collected at each sampling point in the oil tea garden. The collected soil was placed in a fume hood to air dry, and the air-dried soil was ground with a mortar to obtain soil powder. The purpose sieve filters the soil powder to obtain the The samples to be tested on the day are detected by spectrometer. The samples to be tested on the day are obtained Sample spectrum of the day; , as well as They are the preset number of sampling points, soil collection quality, and sieve specifications; Preset a soil improvement cycle , on the first day and every The date of the day is recorded as the soil improvement day.

3. According to claim 1, a nondestructive detection method for heavy metal pollution in oil tea trees is characterized in that: The specific method of obtaining the content of each heavy metal in the sample every day according to the sample spectrum every day is as follows: For In the sample of the day heavy metal content; obtain the The characteristic band of heavy metals and set the The content limit of the heavy metals in the oil tea garden soil The spectrum when the heavy metal content is at the content limit is recorded as the reference spectrum. The curve segment of the characteristic wave band of the heavy metal is recorded as the reference curve segment; In the sample spectrum of the day, The curve segment of the characteristic wave band of the heavy metal is combined with the reference curve segment and the content limit to obtain the In the sample of the day Heavy metal content.

4. According to claim 3, a nondestructive detection method for heavy metal pollution in oil tea trees is characterized in that: The acquisition In the sample of the day The specific calculation formula for the content of heavy metals is as follows: In the formula, Indicates In the sample of the day Heavy metal content; Indicates Content limits of various heavy metals; Indicates In the sample spectrum of the day, The definite integral of the curve segment of the characteristic band of the heavy metal; represents the definite integral of the reference curve segment; represents the hyperbolic tangent function.

5. According to claim 1, a nondestructive detection method for heavy metal pollution in oil tea trees is characterized in that: The method of constructing a daily sample space according to the content of each heavy metal in the daily sample and the content of each heavy metal in all previous samples, and obtaining several clusters in the daily sample space, includes the following specific methods: Construct an N-dimensional sample space, where N is the number of heavy metal types; Day, will Heaven and Earth The samples before the day are recorded as target samples. According to the content of each heavy metal in each target sample, all target samples are placed in the sample space, and each target sample is used as a data point in the sample space to obtain the first Sample space of days; Using DBSCAN clustering algorithm The data points in the sample space of the first day are clustered, and the distance metric is the Euclidean distance between the data points. Several clusters in the sample space of the day.

6. A nondestructive detection method for heavy metal pollution in oil tea trees according to claim 1, characterized in that: The specific method of obtaining the characteristic distance of each soil improvement day according to the plurality of clusters in the sample space of each soil improvement day includes: For Soil Improvement Day The sample space of the soil improvement day contains The cluster of data points corresponding to the soil improvement day is recorded as The target clusters in the sample space of the soil improvement day are The distance between the target cluster center and the origin of the sample space in the sample space of the soil improvement day is recorded as Characteristic distance of soil improvement days.

7. A nondestructive detection method for heavy metal pollution in oil tea trees according to claim 1, characterized in that: The specific calculation formula for obtaining the primary pH value reduction value on the soil improvement day according to the characteristic distance between adjacent soil improvement days is as follows: In the formula, Indicates Primary pH reduction per soil improvement day; Indicates pH reduction value per soil improvement day; Indicates characteristic distance of soil improvement days; Indicates characteristic distance of soil improvement days; Indicates characteristic distance of soil improvement days; Indicates characteristic distance of soil improvement days; Expressing the The differences in characteristic distances of all adjacent soil improvement days before the soil improvement day are traversed, and the maximum value function is taken.

8. A nondestructive detection method for heavy metal pollution in oil tea trees according to claim 6, characterized in that: The specific method of obtaining the change fitting straight line of the soil improvement day according to the daily characteristic distance between adjacent soil improvement days is as follows: For any soil improvement day, the date between the last soil improvement day and the soil improvement day is recorded as a change day, and the characteristic distance of each change day is obtained; A rectangular coordinate system is constructed with the date as the horizontal axis and the characteristic distance of the change day as the vertical axis. Each change day is taken as a coordinate point and placed in the rectangular coordinate system to obtain a scatter plot of the changes in the soil improvement day. The scatter plot of the changes in the soil improvement day is fitted with a straight line using the least squares method to obtain a fitted straight line of the changes in the soil improvement day.

9. A nondestructive detection method for heavy metal pollution in oil tea trees according to claim 1, characterized in that: The method of fitting a straight line according to the change of the soil improvement day, correcting the primary pH value reduction value on the soil improvement day, and obtaining the pH value reduction value on the soil improvement day includes the following specific methods: For any soil improvement day, the primary pH value reduction value on the soil improvement day is corrected according to the root mean square error of the change fitting line on the soil improvement day and the slope of the change fitting line on the soil improvement day to obtain the pH value reduction value on the soil improvement day. The specific calculation formula is: In the formula, represents the pH decrease on the soil improvement day; represents the primary pH reduction on the soil improvement day; The root mean square error of the fitted straight line representing the variation of the soil improvement day; The slope of the fitted straight line representing the change of the soil improvement day; Represents the sigmoid function.

10. A nondestructive detection system for heavy metal pollution in oil tea trees, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the computer program is executed by a processor, the steps of a nondestructive detection method for heavy metal pollution in oil tea trees as described in any one of claims 1 to 9 are implemented.

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