CN111458394B - Method for measuring acid-base content of soil - Google Patents
Method for measuring acid-base content of soil Download PDFInfo
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- CN111458394B CN111458394B CN202010380059.3A CN202010380059A CN111458394B CN 111458394 B CN111458394 B CN 111458394B CN 202010380059 A CN202010380059 A CN 202010380059A CN 111458394 B CN111458394 B CN 111458394B
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- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
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- G01N27/4167—Systems measuring a particular property of an electrolyte pH
Abstract
The invention is suitable for the technical field of chemical component measurement, and provides a method for measuring the acid-base content of soil. The measuring method comprises the following steps: a. soil sampling: collecting soil as a soil sample in a plot where soil is to be measured; b. soil sample preparation: airing the soil sample, sieving with a sieve, and bagging for later use; C. soil measurement: directly titrating the soil suspension; d. and (3) calculating results: and calculating the acid-base content of the soil. The invention uses the acid-base content of soil as a value, when the value is positive, the acid content is represented, and when the value is negative, the alkali content is represented; the soil or release can reach equilibrium fast when measuring, and soil and leaching solution need not separate, have shortened the survey time of soil sample by a wide margin. The measurement result can be used as an evaluation index of soil acidity and alkalinity, and provides a basis for soil acidification monitoring and farmland soil acidification treatment.
Description
Technical Field
The invention belongs to the technical field of chemical component measurement, and particularly relates to a method for measuring the acid-base content of soil.
Background
The pH value of the soil can reflect the strength of the acidity and alkalinity of the soil, but cannot reflect the content of the acidity or alkalinity in the soil. The acid content of soil is currently generally expressed in terms of soil exchangeable acid content, and the alkaline content of soil is evaluated in terms of soil carbonate content. The content of exchangeable acid in soil refers to exchangeable H adsorbed by colloid in soil + 、Al 3+ The sum of the charge equivalent contents of the acidic cations and the acidic substances such as weak organic acids in the soil, and the carbonate content in the soil refers to the sum of the charge equivalent contents of bicarbonate and carbonate in the soil.
The content of exchangeable acid in soil is closely related to its determination method, and its determination principle is that the leaching or leaching filtration method is adopted, and the salt solution containing a certain cation is used as exchanger to make H on the soil colloid + And Al 3+ The leaching solution or leaching solution is measured and titrated with strong alkali NaOH to a pH value of 8.3 as an end point, and the unit is mol/kg as the ratio of the mol number of the consumed strong alkali to the weight of the soil. Typical extractants include non-pH buffered saline (e.g. KCl, naCl, baCl) 2 、MgCl 2 Etc.) and an acetate solution (NaAc, KAc, cuAc) having pH buffering capacity 2 Etc.), the concentration of the extractant varies from 0.1 to 1.0M. Also, neutral salts and weak organic bases are used as extractant, e.g. BaCl 2 Triethanolamine (TEA). The leaching method comprises leaching, centrifuging and continuous leaching, wherein KCl is continuously leachedThe method is most widely applied, but due to K in the KCl leaching method + Is weak with H + And Al 3+ The exchange of the (C) is not easy to complete, the steps are complicated, and the error between the parallel is larger. BaCl 2 Triethanolamine (TEA) extraction method for H in soil + And Al 3+ The exchange of (c) is complete but the measured acid content is too high, and some substances other than acid are also regarded as acids.
The exchangeable acid content determined by the above methods is not actually the true acid content of the soil, since the soil with pH >7 is alkaline, but these methods cannot represent the alkaline content thereof, but can determine the acid content. Similar problems exist in evaluating the alkali content of the soil by using the carbonate content of the soil, namely, the carbonate content can be measured by using the acid soil with the pH value less than 7, so that the existing method cannot completely and correctly reflect the acid or alkali content of the soil, and the soil is required to be separated from the leaching solution by a filtering or centrifuging method during the measurement, and the measurement method is complex and tedious and has long measurement time.
Disclosure of Invention
The invention provides a method for measuring the acid-base content of soil, which aims to solve the problems that the acid-base content measuring method in the prior art cannot accurately reflect the actual acid or base content of the soil, and the soil is required to be separated from leaching solution by a filtering or centrifuging method during measurement, and the measuring method is complex and tedious and has long measuring time.
The scientific principle of the invention is as follows: h is produced due to dissociation or hydrolysis of various components in the soil in aqueous solution + Some will generate OH - Wherein H is generated + With OH - The equal portions will neutralize each other to become H 2 O does not exhibit acid-base properties, and therefore H + And OH (OH) - The difference between the two can lead the soil to show actual acid-base property. The invention provides a cH value as an index of the content of the acidity and the alkalinity of soil. Soil cH value refers to H produced by dissociation and hydrolysis of soil in neutral aqueous solution + And OH (OH) - The ratio of the difference in the amount of (C) to the soil weight can be usedThe formula is:
wherein p represents H generated by dissociation and hydrolysis of acidic substances in soil in neutral aqueous solution + In millimoles (mmol), q represents OH produced by dissociation and hydrolysis of alkaline substances in the soil in neutral aqueous solution - M is the weight (kg) of the soil, cH is an indicator of the acid-base content of the soil and is the actual net H produced per kg of soil in a neutral aqueous solution + Or OH (OH) - In mmol/kg. When p is>q is cH>0, the soil is acidic, and the cH value refers to the acid content; when p is<q，cH<0, the soil is alkaline, and the cH value refers to the alkali content; when p=q, ch=0, the soil is neutral.
Because the various components in the soil dissociate or hydrolyze in water to produce H + Or OH (OH) - The invention adopts a set of combination method to accelerate the dissociation and the hydrolysis of various components in the soil, promotes H + Or OH (OH) - The production of (2) reaches equilibrium rapidly, so that the soil sample measurement time can be shortened greatly.
The embodiment of the invention is realized in such a way that the method for measuring the acid-base content of the soil comprises the following steps:
a. soil sampling: collecting soil as a soil sample in a plot where soil is to be measured;
b. soil sample preparation: airing the soil sample, sieving with a sieve, and bagging for later use;
c. soil measurement: pouring 1000ml of 0.01M KCl solution into a beaker, weighing 1-2g of the soil sample into the KCl solution in the beaker, stirring to form a soil suspension, inserting an electrode of a pH meter into the soil suspension in the beaker, measuring the pH value of the soil suspension, titrating with 0.02M HCl standard solution when the pH value of the soil suspension indicates that the soil suspension is alkaline, and recording the volume of the consumed HCl standard solution when the pH value of the soil suspension indicates that the soil suspension is neutral; when the pH value of the soil suspension indicates that the soil suspension is acidic, titrating by using a 0.02M NaOH standard solution, and when the pH value of the soil suspension indicates that the soil suspension is neutral, recording the volume of the consumed NaOH standard solution as a titration end point;
1000ml of 0.01M KCl solution without adding soil sample is used as a control, 0.02M NaOH standard solution is used for titration to be neutral, and the volume of NaOH standard consumed by the control is recorded;
d. calculating the acid-base content measurement result of the soil:
wherein:
V 1 represents the volume of 0.02M NaOH standard solution consumed by the soil sample in ml;
N 1 the accurate concentration of the NaOH standard solution of 0.02M is expressed in mol/L;
V 2 represents the volume of 0.02M HCl standard solution consumed by the soil sample in ml;
N 2 the accurate concentration of the HCl standard solution of 0.02M is expressed in mol/L;
V 3 represents the volume of 0.02M NaOH standard solution consumed by the control, in ml;
w represents the weight of the soil sample in kg;
cH represents the acid-base content of the soil in mmol/kg; when cH >0, cH value refers to acid content; when cH <0, cH value refers to base content.
Further, in the step a, soil samples are collected along the S-shaped route according to the principles of random, equal quantity and multi-point mixing, 20-30 sampling points of each sample are obtained, the soil collected by each sampling point is mixed, and 0.5kg of soil sample is reserved according to the quartering method.
Further, in the step b, after the soil sample is dried, the soil sample is packaged for standby after passing through a 100-mesh sieve.
Further, in the step c, 1g of the soil sample is weighed and put into 1000ml of 0.01M KCl solution, and then the soil suspension is directly titrated under the stirring of a magnetic stirrer.
Compared with the prior art, the invention has the beneficial effects that:
(1) The invention expresses the acid and alkali content of the soil by using the cH value, the acid content is expressed when the cH value is positive, the alkali content is expressed when the cH value is negative, the expression mode is simple and clear, and the problem of how to uniformly express the acid and alkali content of the soil is solved.
(2) H is generated by dissociation or hydrolysis of various components in the soil in water + Or OH (OH) - The process of the invention is slow, the time for reaching equilibrium is too long, the invention adopts a set of combination method to accelerate the dissociation and the hydrolysis of various components in the soil, and promote H + Or OH (OH) - The production of the method reaches balance rapidly, so that the soil sample measuring time can be shortened greatly, the method is simple and efficient, and the measuring result is accurate.
(3) By measuring the acid-base content of the soil, the acid-base property of the soil can be quantitatively evaluated, and a basis is provided for soil acidification monitoring and application of soil acid modifying agents such as lime and the like in agricultural production.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the following examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
The embodiment of the invention provides a method for measuring the acid-base content of soil, which comprises the following steps:
a. soil sampling: collecting soil as a soil sample in a plot where soil is to be measured;
b. soil sample preparation: airing the soil sample, sieving with a sieve, and bagging for later use;
c. soil measurement: pouring 1000ml of 0.01M KCl solution (namely potassium chloride solution with the concentration of 0.01 mol/L) into a beaker, weighing 1-2g of the soil sample into the KCl solution in the beaker, stirring into a soil suspension, inserting an electrode of a pH meter into the soil suspension in the beaker, measuring the pH value of the soil suspension, titrating with 0.02M HCl standard solution (namely hydrogen chloride solution with the concentration of 0.02 mol/L) when the pH value of the soil suspension indicates that the soil suspension is alkaline, and recording the volume of the consumed HCl standard solution when the pH value of the soil suspension indicates that the soil suspension is neutral; when the pH value of the soil suspension indicates that the soil suspension is acidic, 0.02M HCl standard solution (namely 0.02mol/L sodium hydroxide solution) is used for titration, and when the pH value of the soil suspension indicates that the soil suspension is neutral, the titration end point is used for recording the volume of the consumed NaOH standard solution.
1000ml of 0.01M KCl solution without adding soil sample is used as a control, 0.02M NaOH standard solution is used for titration until the pH value is neutral, and the volume of the NaOH standard solution consumed by the control is recorded;
d. calculating the acid-base content measurement result of the soil:
wherein:
V 1 represents the volume of 0.02M NaOH standard solution consumed by the soil sample in ml;
N 1 the accurate concentration of the NaOH standard solution of 0.02M is expressed in mol/L;
V 2 represents the volume of 0.02M HCl standard solution consumed by the soil sample in ml;
N 2 the accurate concentration of the HCl standard solution of 0.02M is expressed in mol/L;
V 3 represents the volume of 0.02M NaOH standard solution consumed by the control, in ml;
w represents the weight of the soil sample in kg;
cH represents the acid-base content of the soil in mmol/kg; when cH >0, cH value refers to acid content; when cH <0, cH value refers to base content.
In the above embodiment, in step a, in the plot where the soil is to be measured, soil samples are collected along the S-type route according to the principles of "random", "equal amount" and "multipoint mixing", 20 to 30 sampling points of each sample are collected, the soil collected at each sampling point is mixed, and 0.5kg of soil sample is left according to the quartering method. In the step b, after the soil sample is dried, the soil sample is packaged for standby after passing through a 100-mesh sieve. In step c, 1g of the soil sample is weighed and put into 1000ml of 0.01M KCl solution, and then the soil suspension is directly titrated under the stirring of a magnetic stirrer.
The method for measuring the acid-base content of the soil is illustrated by the following two examples:
example 1
The method for measuring the acid-base content of soil of a cultivated layer of a certain sugarcane field comprises the following steps:
step 1: sampling soil; and collecting soil of a cultivated layer as soil samples along an S-shaped route according to the principles of 'random', 'equal quantity' and 'multi-point mixing', wherein 20-30 sampling points of each soil sample are used for collecting soil samples, and the collected soil is mixed to leave 0.5kg of soil samples according to a quartering method.
Step 2: preparing a soil sample; and (5) airing the soil sample, sieving with a 100-mesh sieve, and bagging for later use.
Step 3: 1000ml of 0.01M KCl solution is poured into a beaker, the beaker is placed on a magnetic stirrer, then 1g of soil sample which is sieved by a 100-mesh sieve is weighed and placed into the beaker, the magnetic stirrer is started to stir the soil sample into a soil suspension, then an electrode of a pH meter is inserted into the beaker, and the pH value of the soil suspension is measured to be 3.3.
Step 4: titration was performed with 0.02M NaOH standard solution, and the change in pH of the soil suspension was observed, and when titrated to pH neutral, the volume of NaOH standard solution consumed was 15.30ml.
Step 5: 1000ml of 0.01M KCl solution without soil sample was used as a control, and when titrated to neutral pH with 0.02M NaOH standard solution, the volume of NaOH standard solution consumed by the control was 1.3ml.
Step 6: the acid-base content measurement result of the soil of the cultivated layer of the sugarcane field is calculated:
V 1 represents the volume of 0.02M NaOH standard solution consumed by the soil sample, in ml, V 1 ＝15.30ml。
N 1 Represents the accurate concentration of 0.02M NaOH standard solution, and the unit is mol/L and N 1 ＝0.02mol/L。
V 2 Represents the volume of 0.02M HCl standard solution consumed by the soil sample in ml, V 2 ＝0ml。
N 2 Represents the accurate concentration of 0.02M HCl standard solution, and the unit is mol/L and N 2 ＝0.02mol/L。
V 3 Represents the volume of 0.02M NaOH standard solution consumed by the control, in ml, V 3 ＝1.35ml。
W represents the weight of the soil sample in kg, w=0.001 kg.
From the above data, cH=276 mmol/kg was calculated, and it was found that the sugar cane ground cultivation layer soil was acidic and contained 276mmol/kg of acid.
Example two
The method for measuring the acid-base content of the soil of the cultivated layer of the banana field comprises the following steps:
step 1: sampling soil; and collecting cultivated soil as soil samples along an S-shaped route according to the principles of 'random', 'equal quantity' and 'multi-point mixing', wherein 20-30 sampling points of each soil sample are adopted, and collecting soil samples of 0.5kg are reserved according to a quartering method after mixing the collected soil.
Step 2: preparing a soil sample; and (5) airing the soil sample, sieving with a 100-mesh sieve, and bagging for later use.
Step 3: 1000ml of 0.01M KCl solution was poured into a beaker, placed on a magnetic stirrer, then 1g of the soil sample having been sieved with a 100-mesh sieve was weighed and placed into the beaker, the magnetic stirrer was started, an electrode of a pH meter was inserted into the beaker, and the pH value of the soil suspension was measured to be 8.3.
Step 4: titration was performed with 0.02M HCl standard solution, changes in pH of the soil suspension were observed, and when titrated to pH neutral, the volume of HCl standard solution consumed was 3.95ml.
Step 5: 1000ml of 0.01M KCl solution without soil sample was used as a control, and when titrated to neutral pH with 0.02M NaOH standard solution, the volume of NaOH standard solution consumed by the control was 1.3ml.
Step 6: the acid-base content measurement result of the cultivated layer soil of the banana field is calculated:
V 1 represents the volume of 0.02M NaOH standard solution consumed by the soil sample, in ml, V 1 ＝0ml。
N 1 Represents the accurate concentration of 0.02M NaOH standard solution, and the unit is mol/L and N 1 ＝0.02mol/L。
V 2 Represents the volume of 0.02M HCl standard solution consumed by the soil sample in ml, V 2 ＝3.95ml。
N 2 Represents the accurate concentration of 0.02M HCl standard solution, and the unit is mol/L and N 2 ＝0.02mol/L。
V 3 Represents the volume of 0.02M NaOH standard solution consumed by the control, in ml, V 3 ＝1.35ml。
W represents the weight of the soil sample in kg, w=0.001 kg.
From the above data, cH= -106mmol/kg was calculated, whereby the banana field soil was alkaline and the alkali content was 106mmol/kg of banana field plough layer soil.
In summary, the method for measuring the acid-base content of the soil has the following advantages:
(1) The invention expresses the acid-base content of the soil by using the cH value, the cH value is positive value and expresses the acid content, and the cH value is negative value and expresses the alkaline content, so that the expression mode is simple and clear, and the problem of how to quantitatively express the acid-base content of the soil is solved.
(2) The invention can obtain the acid-base content of the soil through simple measuring steps, the soil and the leaching liquid are not required to be separated during the measurement, the measuring time of the soil sample can be greatly shortened, the measuring method is simple and efficient, and the measuring result is accurate.
(3) By measuring the acid-base content of the soil, the acid-base property of the soil can be quantitatively evaluated, and a basis is provided for soil acidification monitoring and application of soil acid modifying agents such as lime and the like in agricultural production.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.
Claims (4)
1. The method for measuring the acid-base content of the soil is characterized by comprising the following steps of:
a. soil sampling: collecting soil as a soil sample in a plot where soil is to be measured;
b. soil sample preparation: airing the soil sample, sieving with a sieve, and bagging for later use;
c. soil measurement: pouring 1000ml of 0.01M KCl solution into a beaker, weighing 1-2g of the soil sample into the KCl solution in the beaker, stirring to form a soil suspension, inserting an electrode of a pH meter into the soil suspension in the beaker, measuring the pH value of the soil suspension, titrating with 0.02M HCl standard solution when the pH value of the soil suspension indicates that the soil suspension is alkaline, and recording the volume of the consumed HCl standard solution when the pH value of the soil suspension indicates that the soil suspension is neutral; when the pH value of the soil suspension indicates that the soil suspension is acidic, titrating by using a 0.02M NaOH standard solution, and when the pH value of the soil suspension indicates that the soil suspension is neutral, recording the volume of the consumed NaOH standard solution as a titration end point;
1000ml of 0.01M KCl solution without adding soil sample is used as a control, 0.02M NaOH standard solution is used for titration to be neutral, and the volume of NaOH standard consumed by the control is recorded;
d. calculating the acid-base content measurement result of the soil:
wherein:
V 1 represents the volume of 0.02M NaOH standard solution consumed by the soil sample in ml;
N 1 the accurate concentration of the NaOH standard solution of 0.02M is expressed in mol/L;
V 2 represents the volume of 0.02M HCl standard solution consumed by the soil sample in ml;
N 2 the accurate concentration of the HCl standard solution of 0.02M is expressed in mol/L;
V 3 represents the volume of 0.02M NaOH standard solution consumed by the control, in ml;
w represents the weight of the soil sample in kg;
cH represents the acid-base content of the soil in mmol/kg; when cH >0, cH value refers to acid content; when cH <0, cH value refers to base content.
2. The method for measuring the acid-base content of soil according to claim 1, wherein in the step a, soil samples are collected along an S-shaped route according to the principles of 'random', 'equal quantity' and 'multi-point mixing', 20-30 sampling points of each sample are obtained, the soil collected at each sampling point is mixed, and 0.5kg of soil sample is left according to a quartering method.
3. The method for measuring the acid-base content of soil according to claim 1, wherein in the step b, the soil sample is dried, and is packed for standby after passing through a 100-mesh sieve.
4. The method for measuring the acid-base content of soil according to claim 1, wherein in the step c, 1g of the soil sample is weighed and put into 1000ml of 0.01M KCl solution, and then the soil suspension is directly titrated under the stirring of a magnetic stirrer.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102788791A (en) * | 2012-08-10 | 2012-11-21 | 青岛农业大学 | Fast determination method for soil acidity and alkalinity and determination device thereof |
| CN103196905A (en) * | 2013-03-21 | 2013-07-10 | 中国农业大学 | Method for calculating lime application amount in acidified soil |
| CN104713996A (en) * | 2013-12-11 | 2015-06-17 | 中国科学院沈阳应用生态研究所 | Method for determining pH value of soil |
| CN107121522A (en) * | 2017-06-06 | 2017-09-01 | 深圳市华星光电技术有限公司 | A kind of method for detecting photoresistance acid-base value |
-
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102788791A (en) * | 2012-08-10 | 2012-11-21 | 青岛农业大学 | Fast determination method for soil acidity and alkalinity and determination device thereof |
| CN103196905A (en) * | 2013-03-21 | 2013-07-10 | 中国农业大学 | Method for calculating lime application amount in acidified soil |
| CN104713996A (en) * | 2013-12-11 | 2015-06-17 | 中国科学院沈阳应用生态研究所 | Method for determining pH value of soil |
| CN107121522A (en) * | 2017-06-06 | 2017-09-01 | 深圳市华星光电技术有限公司 | A kind of method for detecting photoresistance acid-base value |
Non-Patent Citations (1)
| Title |
|---|
| 不同植茶年限茶园土壤pH缓冲容量;苏有健 等;《应用生态学报》;20141031;第25卷(第10期);第2915-2916页 * |
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