Analysis method for effective states of Pb/Cd in different soils
阅读说明：本技术 一种对不同土壤中Pb/Cd有效态的分析方法 (Analysis method for effective states of Pb/Cd in different soils ) 是由 孙伟 杜丽阳 曹磊 蒋兰 宋贵民 刘翀 苏园 仲崇军 李伟 杨雪昆 佟彤 孙琴 于 2019-11-20 设计创作，主要内容包括：本发明实施例公开了一种对不同土壤中Pb/Cd有效态的分析方法,包括：S100、将至少两种不同的无机酸复配,形成多组复合无机酸提取剂；S200、采用所述复合无机酸提取剂分别对土壤样本进行提取,得到多个待测液；S300、对多个所述待测液中的Pb有效态和Cd有效态各自进行测定,得到多组Pb/Cd有效态含量；S400、将得到的多组Pb/Cd有效态含量各自与土壤中Pb/Cd全量和有机质含量进行相关性分析,筛选得到呈显著正相关或极显著正相关的复合无机酸提取剂。本发明基于无机酸复配体系对不同土壤进行特异性分析,解决现有技术中常规方式在针对Pb/Cd有效态特异性监测中误差较大,对后期监测造成一定影响的问题。(The embodiment of the invention discloses an analysis method for effective states of Pb/Cd in different soils, which comprises the following steps: s100, compounding at least two different inorganic acids to form a plurality of groups of composite inorganic acid extracting agents; s200, extracting soil samples by adopting the composite inorganic acid extractant respectively to obtain a plurality of solutions to be detected; s300, respectively determining the Pb effective state and the Cd effective state in the liquid to be detected to obtain a plurality of groups of Pb/Cd effective state contents; s400, respectively carrying out correlation analysis on the obtained effective state contents of the multiple groups of Pb/Cd and the total content and organic matter content of Pb/Cd in the soil, and screening to obtain the composite inorganic acid extractant which is in a significant positive correlation or a very significant positive correlation. The invention carries out specificity analysis on different soils based on an inorganic acid compound system, and solves the problems that the conventional mode in the prior art has larger error in the specificity monitoring aiming at the effective state of Pb/Cd and causes certain influence on the later monitoring.)
1. An analysis method for effective states of Pb/Cd in different soils is characterized by comprising the following steps:
s100, compounding at least two different inorganic acids to form a plurality of groups of composite inorganic acid extracting agents;
s200, extracting soil samples by adopting the composite inorganic acid extractant respectively to obtain a plurality of solutions to be detected;
s300, respectively determining the Pb effective state and the Cd effective state in the liquid to be detected to obtain a plurality of groups of Pb/Cd effective state contents;
s400, respectively carrying out correlation analysis on the obtained effective state contents of the multiple groups of Pb/Cd and the total content and organic matter content of Pb/Cd in the soil, and screening to obtain the composite inorganic acid extractant which is in a significant positive correlation or a very significant positive correlation.
2. The method according to claim 1, wherein in step S100, the inorganic acid is at least two selected from hydrochloric acid, nitric acid, perchloric acid, sulfuric acid, hydroiodic acid, and hydrobromic acid.
3. The method for analyzing the available state of Pb/Cd in different soils as claimed in claim 1 or 2, wherein the step S200 further comprises sampling a soil sample and then extracting, and the sampling process of the soil sample comprises:
s201, taking the maximum diameter of the surface of a soil area to be detected as a long edge and the maximum diameter of an edge perpendicular to the long edge as a short edge, dividing the long edge into 3-5 equal parts, and dividing the short edge into 2-3 equal parts to construct and form a plurality of sampling areas;
s202, at least two sampling points are selected in each sampling area, and 2-4 samples with different vertical heights are taken from each sampling point;
s203, mixing and screening the samples obtained in each sampling area to form soil samples, wherein each sampling area corresponds to one soil sample.
4. The method for analyzing the effective state of Pb/Cd in different soils as claimed in claim 1 or 2, wherein the extraction process in step S200 adopts a microwave digestion instrument, or adopts the following steps:
s204, adding concentrated nitric acid into the wet soil sample, and evaporating to dryness at the temperature of 110-130 ℃ to obtain a dried substance;
s205, adding a composite inorganic acid extracting agent into the dried material, and evaporating to dryness at the temperature of 140-160 ℃;
s206, repeating the step S205 for not less than 2 times, and adding at least one inorganic acid in the composite inorganic acid extracting agent into the obtained residue until the residue is dissolved to obtain a liquid to be detected.
5. The method for analyzing the available state of Pb/Cd in different soils as claimed in claim 1 or 2, wherein in step S400, the correlation analysis step specifically comprises:
s401, determining the extraction rate of the Pb/Cd effective state in each soil sample;
s402, respectively constructing fitting curves of the obtained Pb available state content and the Pb total amount in soil, the obtained Cd available state content and the Cd total amount in soil, the obtained Pb available state content and the organic matter content in soil, and the obtained Cd available state content and the obtained Cd organic matter content in soil, and comparing the fitting curves of soil samples extracted by different composite inorganic acid extracting agents on the fitting curves;
s403, verifying the comparison result in the steps S401 and S402, and screening to determine a composite inorganic acid extractant; wherein, the calculation formula of the extraction rate of the Pb/Cd effective state is as follows: w is m/n multiplied by 100 percent, m is the effective state content of Pb/Cd, and n is the total content of Pb/Cd in the soil.
6. The method for analyzing the available state of Pb/Cd in different soils as claimed in claim 5, wherein the verification of step S403 specifically comprises:
s4031, verifying the extraction rate of the Pb/Cd effective state: when the absolute values of the extraction rate of the Pb effective state and the extraction rate of the Cd effective state in each soil sample adopting the same composite inorganic acid extractant are respectively not less than 85 percent and the absolute values of the extraction rates of the Pb effective state and the Cd effective state are respectively not less than 90 percent, the soil samples are considered to be in extremely obvious positive correlation; when the absolute value of each is not less than 80% and the homogeneity is not less than 85% and less than 90%, it is considered to be significantly positively correlated;
s4032, alignment of the fitted curves: when the deviation values of the four fitting curves in each soil sample adopting the same composite inorganic acid extractant are less than 0.01, the soil samples are considered to be in extremely obvious positive correlation; when no more than two of the deviation values are greater than 0.01 and less than 0.05, and the others are less than 0.01, it is considered that a significant positive correlation is present.
7. The method for analyzing the available state of Pb/Cd in different soils according to claim 3, wherein in step S202, a soil sampler is used for sampling the soil, and the soil sampler comprises a sampling storage part (1) and a soil drilling part (2) which are sequentially arranged from top to bottom, the sampling storage part (1) at least comprises a storage cavity (12) and a shell (13) which are sequentially sleeved from inside to outside and connected through an elastic resetting element (11), and a gap is formed between the storage cavity (12) and the shell (13);
a plurality of soil loosening blocks (121) which are inclined towards the shell (13) and are formed into a wedge shape are arranged on the outer surface of the storage cavity (12), the gap is used for placing the soil loosening blocks (121), and a plurality of through holes which are used for accommodating the soil loosening blocks (121) to penetrate through and extend to the outside of the shell (13) are formed in the side wall of the shell (13) in a penetrating manner;
the storage cavity (12) is internally formed into a plurality of soil storage cavities (122) from top to bottom, a sampling port (123) penetrating to the outside of the shell (13) is formed in each soil storage cavity (122), a sampling plate (124) is slidably arranged in each soil storage cavity (122), and at least part of the sampling plate (124) is used for sampling from the outside of the shell (13) through the sampling port (123).
8. A method for analyzing the available state of Pb/Cd in different soils as claimed in claim 7, wherein the elastic restoring element (11) comprises a torsion spring and a tension spring, the torsion spring and the tension spring are connected in sequence from the housing (13) to the storage chamber (12), and the tension spring extends along the horizontal direction along the elastic direction.
9. The method for analyzing the available state of Pb/Cd in different soils is characterized in that a sliding groove extending along the circumferential direction of the outer side wall in the track direction is formed on the outer side wall of the storage cavity (12), and the elastic reset element (11) comprises an extension spring with one end connected with the inner side wall of the shell (13) and one end arranged in the sliding groove through a sliding block and extending along the horizontal direction in the elastic direction.
10. The method for analyzing the available state of Pb/Cd in different soils as claimed in any one of claims 7 to 9, wherein a pushing mechanism for pushing the sampling plate (124) in a horizontal direction is connected to the sampling plate (124).
Technical Field
The embodiment of the invention relates to the field of analysis methods for effective states of Pb/Cd in soil, in particular to an analysis method for the effective states of Pb/Cd in different soils.
Background
With the rapid development of the industry and mining industry in China and unreasonable use of heavy metal nuclides by human beings, the heavy metal pollution of soil is increasingly aggravated; heavy metals have the characteristics of poor mobility, long residence time, difficulty in being degraded by microorganisms and the like in soil, and once entering a food chain through media such as water, plants and the like, the heavy metals can seriously threaten human health. In the past, the higher the total amount of heavy metals in soil, the greater the potential environmental hazard, however, with the increasingly deep research on the forms of heavy metal elements, people increasingly recognize that the correlation between the environmental behavior and the ecological effect of heavy metals and the total amount of heavy metals in soil is not significant, but mainly depends on the existing forms of heavy metals in soil and the quantitative proportion of various form components, namely the effective states of heavy metal elements. Therefore, the effective state content of the elements in the soil can provide specific quantitative indexes for the ploughing-suitable degree, basic data are provided for environment monitoring and pollution evaluation, and meanwhile, for an agricultural environment system, the effective state content of the heavy metals in the soil is analyzed, and the purpose of effectively monitoring the agricultural environment can be achieved.
In the agricultural environment system of China, Cd and Pb are typical heavy metal pollutants harmful to crops, so that the effective state monitoring of Cd and Pb heavy metal ions is particularly important in the agricultural environment monitoring of China.
In the process of monitoring the effective state of heavy metals, extraction is also one of the key links, and at present, chemical reagent extraction methods are mostly adopted for the effective state of heavy metals in soil at home and abroad, such as common chelating extractant, neutral salt extractant and single dilute acid extractant. The extraction method of the chelating extractant (such as a DPTA extractant) is adopted, and because the chelating property of heavy metal ions in soil is strong, other heavy metal ions which cannot be absorbed and utilized by plants are often extracted by the chelating extractant, and the specificity aiming at the effective state of Pb/Cd is often relatively deficient, so that the measurement result is larger; neutral salt extractant is adopted for leaching, and the extraction amount is low, and high background value is easily caused by high salt concentration, so that later-stage measurement is difficult and errors are large; and a single dilute acid extractant is adopted for leaching, so that the leaching rate is low, the numerical value is easily lower than the actual value, the actual effective state contents of Cd and Pb in the environment cannot be well reflected, and certain influence and misjudgment are caused on the monitoring of the later environment.
Disclosure of Invention
Therefore, the embodiment of the invention provides an analysis method for effective states of Pb/Cd in different soils, which is used for carrying out specificity analysis on different soils based on an inorganic acid compound system and solving the problem that a conventional mode in the prior art has a large error in specificity monitoring for the effective states of Pb/Cd and causes certain influence on later-stage monitoring.
In order to achieve the above object, an embodiment of the present invention provides the following:
in an embodiment of the present invention, a method for analyzing effective states of Pb/Cd in different soils is provided, including:
s100, compounding at least two different inorganic acids to form a plurality of groups of composite inorganic acid extracting agents;
s200, extracting soil samples by adopting the composite inorganic acid extractant respectively to obtain a plurality of solutions to be detected;
s300, respectively determining the Pb effective state and the Cd effective state in the liquid to be detected to obtain a plurality of groups of Pb/Cd effective state contents;
s400, respectively carrying out correlation analysis on the obtained effective state contents of the multiple groups of Pb/Cd and the total content and organic matter content of Pb/Cd in the soil, and screening to obtain the composite inorganic acid extractant which is in a significant positive correlation or a very significant positive correlation.
In a preferred embodiment of the present invention, in step S100, the inorganic acid is at least two selected from the group consisting of hydrochloric acid, nitric acid, perchloric acid, sulfuric acid, hydroiodic acid, and hydrobromic acid.
As a preferable scheme of the present invention, the step S200 further includes sampling the soil sample and then extracting, and the sampling process of the soil sample includes:
s201, taking the maximum diameter of the surface of a soil area to be detected as a long edge and the maximum diameter of an edge perpendicular to the long edge as a short edge, dividing the long edge into 3-5 equal parts, and dividing the short edge into 2-3 equal parts to construct and form a plurality of sampling areas;
s202, at least two sampling points are selected in each sampling area, and 2-4 samples with different vertical heights are taken from each sampling point;
s203, mixing and screening the samples obtained in each sampling area to form soil samples, wherein each sampling area corresponds to one soil sample.
As a preferred scheme of the present invention, the extraction process in step S200 adopts a microwave digestion apparatus, or adopts the following steps:
s204, adding concentrated nitric acid into the wet soil sample, and evaporating to dryness at the temperature of 110-130 ℃ to obtain a dried substance;
s205, adding a composite inorganic acid extracting agent into the dried material, and evaporating to dryness at the temperature of 140-160 ℃;
s206, repeating the step S205 for not less than 2 times, and adding at least one inorganic acid in the composite inorganic acid extracting agent into the obtained residue until the residue is dissolved to obtain a liquid to be detected.
As a preferred embodiment of the present invention, in step S400, the correlation analysis step specifically includes:
s401, determining the extraction rate of the Pb/Cd effective state in each soil sample;
s402, respectively constructing fitting curves of the obtained Pb available state content and the Pb total amount in soil, the obtained Cd available state content and the Cd total amount in soil, the obtained Pb available state content and the organic matter content in soil, and the obtained Cd available state content and the obtained Cd organic matter content in soil, and comparing the fitting curves of soil samples extracted by different composite inorganic acid extracting agents on the fitting curves;
s403, verifying the comparison result in the steps S401 and S402, and screening to determine a composite inorganic acid extractant; wherein, the calculation formula of the extraction rate of the Pb/Cd effective state is as follows: w is m/n multiplied by 100 percent, m is the effective state content of Pb/Cd, and n is the total content of Pb/Cd in the soil.
As a preferred embodiment of the present invention, the verification in step S403 specifically includes:
s4031, verifying the extraction rate of the Pb/Cd effective state: when the absolute values of the extraction rate of the Pb effective state and the extraction rate of the Cd effective state in each soil sample adopting the same composite inorganic acid extractant are respectively not less than 85 percent and the absolute values of the extraction rates of the Pb effective state and the Cd effective state are respectively not less than 90 percent, the soil samples are considered to be in extremely obvious positive correlation; when the absolute value of each is not less than 80% and the homogeneity is not less than 85% and less than 90%, it is considered to be significantly positively correlated;
s4032, alignment of the fitted curves: when the deviation values of the four fitting curves in each soil sample adopting the same composite inorganic acid extractant are less than 0.01, the soil samples are considered to be in extremely obvious positive correlation; when no more than two of the deviation values are greater than 0.01 and less than 0.05, and the others are less than 0.01, it is considered that a significant positive correlation is present.
As a preferred scheme of the present invention, in step S202, a soil sampler is used to sample soil, and the soil sampler includes a sampling storage portion and a soil drilling portion sequentially arranged from top to bottom, the sampling storage portion at least includes a storage cavity and a housing sequentially sleeved from inside to outside and connected by an elastic resetting element, and a gap is formed between the storage cavity and the housing;
a plurality of soil loosening blocks which are inclined towards the shell and form a wedge shape are arranged on the outer surface of the storage cavity, the gap is used for placing the soil loosening blocks, and a plurality of through holes which are used for accommodating the soil loosening blocks to penetrate through and extend to the outer part of the shell are formed in the side wall of the shell in a penetrating manner;
the inside top-down of storage chamber forms a plurality of soil and deposits the chamber, and every be formed with in the soil deposits the chamber and link up to the outside sample connection of shell, every be provided with the sampling plate in the soil deposits the chamber slidable, just the sampling plate is used for partly at least the process the sample connection extends to the outside sample of shell.
As a preferable aspect of the present invention, the elastic restoring member includes a torsion spring and an extension spring, which are sequentially connected from the housing to the storage chamber and have an elastic direction extending in a horizontal direction.
As a preferable aspect of the present invention, a sliding groove extending along a track direction along a circumferential direction of the outer side wall is formed on the outer side wall of the storage chamber, and the elastic reset element includes an extension spring having one end connected to the inner side wall of the housing and one end extending along a horizontal direction through an elastic direction in which a slider is disposed in the sliding groove.
As a preferable aspect of the present invention, the sampling plate is connected with a pushing mechanism for pushing the sampling plate in a horizontal direction.
The embodiment of the invention has the following advantages:
1. compounding at least two inorganic acids to form an extractant of a compound system, effectively ensuring the extraction of the effective state of Pb/Cd in soil, and improving the accuracy of later-stage monitoring;
2. the screening method is adopted according to different soil samples, the extractant of the Pb/Cd effective state is obtained in a targeted manner according to the specificity difference of each soil sample, and the influence of other heavy metal ions on the extraction process is reduced;
3. the correlation analysis of the effective state content, the total amount and the organic matter content is adopted to carry out targeted identification, so that the accuracy of the obtained extractant for soil extraction at the later stage is ensured.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.
FIG. 1 is a flowchart of a method for analyzing the available state of Pb/Cd according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a soil sampler according to an embodiment of the present invention;
FIG. 3 is a partial top view of a reservoir in accordance with an embodiment of the present invention;
FIG. 4 is a schematic view of a partial structure of a spacer and a card slot in an embodiment of the present invention;
FIG. 5 is a schematic view of a portion of a storage cavity and a ripping block according to an embodiment of the present disclosure;
FIG. 6 is a graph showing the average Pb extraction of three complex inorganic acid extractants according to the embodiment of the present invention;
FIG. 7 is a graph showing the mean Cd extraction yield of three complex inorganic acid extractants according to the embodiment of the present invention;
FIG. 8 is a graph comparing the extraction yields of three complex inorganic acid extractants in accordance with an embodiment of the present invention;
FIG. 9 is a graph fitted with a correlation between the heavy metal Pb extracted by three extractants and the total amount of Pb in a soil sample according to an embodiment of the present invention;
FIG. 10 is a fitting graph of the correlation between heavy metal Cd extracted by three extractants and the total amount of Cd in a soil sample according to the embodiment of the invention;
FIG. 11 is a fitted graph of the correlation between the heavy metal Pb extracted by three extractants and the organic matter in a soil sample according to an embodiment of the invention;
fig. 12 is a fitting graph of the correlation between heavy metal Cd extracted by three extractants and organic matter in a soil sample according to an embodiment of the present invention.
In the figure:
1-a sampling storage part; 2-drilling the soil part;
11-an elastic return element; 12-a storage chamber; 13-a housing;
121-loose soil blocks; 122-a soil storage chamber; 123-a sampling port; 124-a sampling plate; 125-a separator plate; 126-card slot; 127-a handheld wand;
1241-a stop block; 1251-fastener; 1261-cartridge;
21-tooth-shaped earth drilling member.
Detailed Description
The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in FIG. 1, the invention provides an analysis method for effective states of Pb/Cd in different soils, which comprises the following steps:
s100, compounding at least two different inorganic acids to form a plurality of groups of composite inorganic acid extracting agents;
s200, extracting soil samples by adopting the composite inorganic acid extractant respectively to obtain a plurality of solutions to be detected;
s300, respectively determining the Pb effective state and the Cd effective state in the liquid to be detected to obtain a plurality of groups of Pb/Cd effective state contents;
s400, respectively carrying out correlation analysis on the obtained effective state contents of the multiple groups of Pb/Cd and the total content and organic matter content of Pb/Cd in the soil, and screening to obtain the composite inorganic acid extractant which is in a significant positive correlation or a very significant positive correlation.
In a preferred embodiment of the present invention, in step S100, the inorganic acid is selected from at least two of hydrochloric acid, nitric acid, perchloric acid, sulfuric acid, hydroiodic acid, and hydrobromic acid.
In a further preferred embodiment, in order to make the obtained soil sample more referential and better reflect the soil characteristics in the area, the step S200 further includes sampling the soil sample and then extracting, and the sampling process of the soil sample includes:
s201, taking the maximum diameter of the surface of a soil area to be detected as a long edge and the maximum diameter of an edge perpendicular to the long edge as a short edge, dividing the long edge into 3-5 equal parts, and dividing the short edge into 2-3 equal parts to construct and form a plurality of sampling areas;
s202, at least two sampling points are selected in each sampling area, and 2-4 samples with different vertical heights are taken from each sampling point;
s203, mixing and screening the samples obtained in each sampling area to form soil samples, wherein each sampling area corresponds to one soil sample.
In a preferred embodiment of the present invention, the extraction process in step S200 is performed by using a microwave digestion apparatus, or by using the following steps:
s204, adding concentrated nitric acid into the wet soil sample, and evaporating to dryness at the temperature of 110-130 ℃ to obtain a dried substance;
s205, adding a composite inorganic acid extracting agent into the dried material, and evaporating to dryness at the temperature of 140-160 ℃;
s206, repeating the step S205 for not less than 2 times, and adding at least one inorganic acid in the composite inorganic acid extracting agent into the obtained residue until the residue is dissolved to obtain a liquid to be detected.
In a further preferred embodiment, in order to make the whole correlation analysis more fit with the characteristics of the existing form of Pb/Cd in the soil, so as to further more effectively control the whole monitoring process and screen a better extracting agent, in step S400, the correlation analysis step specifically is:
s401, determining the extraction rate of the Pb/Cd effective state in each soil sample;
s402, respectively constructing fitting curves of the obtained Pb available state content and the Pb total amount in soil, the obtained Cd available state content and the Cd total amount in soil, the obtained Pb available state content and the organic matter content in soil, and the obtained Cd available state content and the obtained Cd organic matter content in soil, and comparing the fitting curves of soil samples extracted by different composite inorganic acid extracting agents on the fitting curves;
s403, verifying the comparison result in the steps S401 and S402, and screening to determine a composite inorganic acid extractant; wherein, the calculation formula of the extraction rate of the Pb/Cd effective state is as follows: w is m/n multiplied by 100 percent, m is the effective state content of Pb/Cd, and n is the total content of Pb/Cd in the soil.
In a further preferred embodiment, the verification in step S403 specifically includes:
s4031, verifying the extraction rate of the Pb/Cd effective state: when the absolute values of the extraction rate of the Pb effective state and the extraction rate of the Cd effective state in each soil sample adopting the same composite inorganic acid extractant are respectively not less than 85 percent and the absolute values of the extraction rates of the Pb effective state and the Cd effective state are respectively not less than 90 percent, the soil samples are considered to be in extremely obvious positive correlation; when the absolute value of each is not less than 80% and the homogeneity is not less than 85% and less than 90%, it is considered to be significantly positively correlated;
s4032, alignment of the fitted curves: when the deviation values of the four fitting curves in each soil sample adopting the same composite inorganic acid extractant are less than 0.01, the soil samples are considered to be in extremely obvious positive correlation; when no more than two of the deviation values are greater than 0.01 and less than 0.05, and the others are less than 0.01, it is considered that a significant positive correlation is present.
In step S202, a soil sampler is used for sampling soil, and as shown in fig. 2-5, the soil sampler includes a sampling storage part 1 and a soil drilling part 2 which are sequentially arranged from top to bottom, the sampling storage part 1 at least includes a
a plurality of soil loosening blocks 121 which are formed in a wedge shape with the inclined surfaces facing the housing 13 are arranged on the outer surface of the
the interior of the
Of course, since the gap between the
As mentioned above, the elastic restoring element 11 is required to be able to be twisted and to be able to be stretched to adjust the size of the gap, and at the same time, the twisted arrangement is able to ensure that the
Further, in order to enable the
In another preferred embodiment of the present invention, a sliding groove extending along a track direction along a circumferential direction of an outer side wall is formed on the outer side wall of the
In a further preferred embodiment, in order to enable the sampling plate 124 to better protrude out of the sampling port 123 for sampling, a pushing mechanism for pushing the sampling plate 124 in a horizontal direction is connected to the sampling plate 124.
Meanwhile, in order to prevent the soil between two adjacent soil storage cavities 122 from interfering with each other, in a preferred embodiment, two adjacent soil storage cavities 122 are separated by a
a
In a further preferred embodiment, in order to enable a plurality of sampling plates 124 to be pushed simultaneously, the pushing mechanism includes a handheld rod 127 disposed in the
In a further preferred embodiment, a through hole is formed in the
In order to better realize sampling and avoid the falling-off of the sampling plate 124, a stop 1241 is formed at an upward protrusion of one end of the sampling plate 124, which is far away from the sampling port 123, and the height of the stop 1241 is greater than that of the sampling port 123, and the height of the sampling plate 124, which is not provided with the stop 1241, is less than that of the sampling port 123. Of course, the side of the sampling plate 124 may also be provided with a baffle plate with a height higher than the height of the soil-containing portion of the sampling plate 124 and lower than the height of the sampling port 123, so as to prevent the taken soil sample from falling off.
In a preferred embodiment of the present invention, a plurality of the soil blocks 121 are disposed at equal intervals along the outer circumferential surface of the
a gap is formed in a surface portion of each of the loose soil blocks 121 connected to the
In a further preferred embodiment, in order to enable the earth-boring portion 2 to better bore into the soil, the width of the end of the earth-boring portion 2 remote from the sample storage portion 1 is smaller than the width of the sample storage portion 1, and the end of the earth-boring portion 2 remote from the sample storage portion 1 is provided with a toothed earth-boring member 21.
The following is further illustrated by specific examples. And measuring the contents of the Pb effective state and the Cd effective state by using graphite furnace atomic absorption spectroscopy.
A certain piece of barren land soil of a forest near a cold water river basin in Tongzhou district of Beijing is selected as an object, and the research land block historically belongs to a sewage irrigation area. Since the last 60 th century, part of agricultural land in Tongzhou district begins to irrigate by using the Tonghui river, the cool water river and the water from the general channel, mainly receives the domestic and industrial wastewater in Beijing, the largest sewage receiving river in Beijing and the main irrigation water source in the south suburb in Beijing, and the history of pollution irrigation is over 50 years by now.
And (3) carrying out point collection on 6 mixed soil samples with the surface layer of 0-20 cm in the research area range, wherein each soil sample weighs about 1 kg. After the soil sample is recovered, firstly removing plant residues, stones and other invaders in the soil, naturally drying and grinding the soil in a shady and cool and ventilated place, and sealing and storing the soil for later use after passing through a nylon screen of 20 meshes and 100 meshes. The 6 soil samples were respectively designated as S1, S2, S3, S4, S5 and S6, and the physicochemical properties thereof are shown in table 1. Wherein, the total amount of Pb and the total amount of Cd in the soil sample are calculated according to a method for measuring the total amount of Pb/Cd in the soil by a mixed acid digestion method described in GB/T17141-1997.