CN110964533A

CN110964533A - Composition for preventing soil loss by inducing precipitation of calcium carbonate using microorganism and method for preventing soil loss using same

Info

Publication number: CN110964533A
Application number: CN201910827252.4A
Authority: CN
Inventors: 南景弼; 郑贤溶; 金庠贤
Original assignee: SNU R&DB Foundation
Current assignee: SNU R&DB Foundation
Priority date: 2018-10-01
Filing date: 2019-09-02
Publication date: 2020-04-07
Anticipated expiration: 2039-09-02
Also published as: CN110964533B; KR101949655B1

Abstract

The invention relates to a composition for preventing soil loss, which comprises the following components: a culture solution of Bacillus pasteurii (Sporosarcina pasteurii), urea and calcium, wherein the ratio of urea to calcium is the same, and the concentration of each is 1M or less.

Description

Composition for preventing soil loss by inducing precipitation of calcium carbonate using microorganism and method for preventing soil loss using same

Technical Field

The present invention relates to a soil loss prevention composition for inducing precipitation of calcium carbonate using a microorganism of bacillus pasteurii (Sporosarcina pasteuri) and a soil loss prevention method using the same, and more particularly, to a method for preventing soil loss due to rainfall.

Background

Microbial Induced Calcium Precipitation (MICP) is generally the result of Biomineralization (Biomineralization) by the urease reaction in the natural environment, a reaction that precipitates calcium carbonate (cacite, CaCO3) on the surface of the microorganism. The cell membrane of the microorganism has a (-) charge attracting the surrounding environment to include Ca²⁺Inside, various (+) cations, thereby producing CaCO in its own cell membrane₃The above reaction is achieved by a ureolytic enzyme called urease.

Urease is a catalytic enzyme that hydrolyzes urea into ammonia and carbonate ions, and the ammonia produced can raise the surrounding pH, providing a favorable environment for the production of calcium carbonate. Urea present in nature is decomposed by urease of microorganisms to produce NH₃And H₂CO₃NH formed₃And H₂CO₃The carbonate ions and ammonium ions are decomposed in water, and the carbonate ions generated at this time react with calcium ions attached to cell walls of microorganisms to generate calcium carbonate. The reaction mechanism is as follows:

CO(NH₂)₂+2H₂O→2NH₃+H₂CO₃

Ca²⁺+Cell→Cell-Ca²⁺

Cell-Ca²⁺+CO₃ ^2-→Cell-CaCO₃

examples of the microorganism having the MICP ability include Bacillus pasteurianus (Sporosarcina pasteurii), Bacillus urealyticus (Sporosarcina Ureae), Proteus vulgaris (Proteus vulgaris), Bacillus sphaericus (Bacillus sphaericus), Myxococcus xanthus, Proteus mirabilis, and helicobacter pylori (helicobacter pylori).

MICP can be used as a biological application method for purifying environment and developing building materials, and has the advantage of no associated problems such as environmental pollution and the like unlike a physical and chemical method.

Disclosure of Invention

Technical problem to be solved by the invention

Based on the above background, the present inventors have completed the present invention by finding the optimum concentration and combination ratio of urea and calcium in a composition for preventing soil erosion using bacillus pasteurii (Sporosarcina paseurii) among MICP microorganisms and confirming that the organic matter content and soil particle size of soil have an influence on the amount of calcium carbonate precipitation when it is applied to a method for preventing soil erosion.

The invention aims to provide a composition for preventing soil loss, which improves the efficiency of enhancing the hardness of soil through calcium carbonate precipitation.

It is still another object of the present invention to provide a method for preventing soil erosion, which can adjust the number of times of injecting a composition for preventing soil erosion based on the size of soil particles and the organic matter content of soil.

However, the technical problems to be solved by the present invention are not limited to the above-mentioned technical problems, and other technical problems not mentioned will be clearly understood by those of ordinary skill in the art from the following description.

Means for solving the problems

According to an embodiment of the present invention, there is provided a composition for preventing soil loss, including: a culture solution of Bacillus pasteurii (Sporosarcina pasteurii), urea and calcium, wherein the ratio of urea to calcium is the same, and the concentration of each is 1M or less.

According to one side, the urea and calcium concentrations were 450 mM.

According to one aspect, the pasteuria broth is pasteuria cultivated in batch in a composition comprising 6g/L urea and 30g/L Tryptic soy broth (Tryptic soy broth) medium, the volume ratio of said composition to headspace of said batch being from 1: 7.8 to 1: 8.3, performed at 180rpm for 24 hours at 30 ℃.

According to one side, the OD value of the pasteuria bacillus culture is 6.

According to one side, the volume of the pasteuria bacillus culture is 1/6 the volume of the soil loss prevention composition.

According to another embodiment of the present invention, there is provided a soil-loss prevention method including the steps of: step 1, measuring the organic matter content of soil; a step 2 of injecting the composition for preventing soil loss according to any one of claims 1 to 5 into soil, wherein the composition is injected 5 times or more in the step 2 when the organic content of the soil measured in the step 1 is 2.5% or more; when the content of organic matter is 0%, the composition is injected more than 2 times.

According to one aspect, the particle size of the soil is 75 μm to 1000 μm.

According to one side, the soil loss is due to rainfall.

According to one aspect, the soil is heavy metal contaminated soil.

ADVANTAGEOUS EFFECTS OF INVENTION

The soil loss prevention composition of the present invention includes urea and calcium in the same ratio, thereby maximizing the efficiency of enhancing soil hardness by calcium carbonate precipitation.

In addition, the soil erosion prevention method of the present invention considers the organic matter content and the particle size of the soil, adjusts the injection frequency of the composition for preventing soil erosion, and realizes a high erosion reduction rate.

The effects of the present invention are not limited to the above-described effects, and all effects derived from the configuration of the present invention described in the embodiments of the present invention or the claims should be included.

Drawings

FIG. 1 is a graph showing the measurement of the increase in ammonia concentration and the decrease in calcium concentration based on the precipitation of calcium carbonate by Bacillus pasteurii urea hydrolysis in solutions of various urea and calcium concentrations.

FIG. 2 is a graph showing the amounts of precipitated calcium carbonate measured at urea and calcium concentrations of 200mM, 450mM and 1000mM, and the relationship between the amounts of precipitated calcium carbonate and the penetration resistance.

FIG. 3 is a graph showing the amount of precipitated calcium carbonate based on the number of injections into sand and the relationship between the amount of precipitation and penetration resistance when treated with urea and a composition having a calcium concentration of 450 mM.

FIG. 4 is a graph showing the amount of precipitated calcium carbonate based on the particle size of soil when treated with urea and a composition having a calcium concentration of 450mM, and the relationship between the amount of precipitation and penetration resistance.

FIG. 5 is a graph showing the state of precipitation of calcium carbonate based on the organic content of soil when treated with urea and a composition having a calcium concentration of 450 mM.

FIG. 6 is a graph showing the change in the number of injections of the soil erosion preventing composition of the present invention into a plate-shaped test piece of sandy soil or loam.

FIG. 7 is a drawing showing a sandy soil plate formed by injecting a composition for preventing soil loss according to the present invention into a plate-shaped test piece of sandy soil or loam, and observing the cohesive force of the test piece.

Fig. 8 is a diagram showing a comparison of the rainfall-based soil erosion prevention rates when the soil erosion prevention method of the present invention is applied to sandy soil.

FIG. 9 is a graph showing a comparison of the rainfall-based soil loss prevention rates when the soil loss prevention method of the present invention is applied to loam.

Fig. 10 is a graph showing the reduction rate of soil erosion when the method for preventing soil erosion according to the present invention is applied to solid soil having organic matter contents of 2.0% (soil 1), 0.8% (soil 2), and 1.4% (soil 3), and then exposed to rainfall at levels of 8.5 ° and 33 mm/hr.

FIG. 11 shows urea hydrolysis rate and OD based on headspace volume in terms of oxygen amount₆₀₀A graph of the values of (a).

Detailed Description

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, various modifications can be made to the embodiments described below, and the scope of the claims of the present patent application is not limited to the embodiments described below. It is intended that all modifications, equivalents and alternatives to the embodiments be included within the scope of the claims.

The terminology used in the embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments. Where not otherwise stated in the context, singular expressions include plural meanings. In the present specification, the terms "comprising" or "having" are used to express that there are the features, numerals, steps, operations, constituent elements, components or combinations thereof described in the specification, and do not exclude that there are one or more other features, numerals, steps, operations, constituent elements, components or combinations thereof, or additional functions.

All terms used herein, including technical or scientific terms, have the ordinary meaning as understood by one of ordinary skill in the art without further definition. The terms commonly used in the art and commonly defined by the dictionary should be understood as meaning consistent with the general contents of the related art, and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

In the description with reference to the drawings, the same constituent elements are denoted by the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. In describing the embodiments, when it is judged that a detailed description of the related well-known art may unnecessarily obscure the embodiments, a detailed description thereof will be omitted.

In the present invention, bacillus pasteurii (Sporosarcina pasteurii) is a microorganism belonging to a bacillus strain, and urease (urease) as a urea hydrolase is produced in an environment in which urea exists.

The present inventors have achieved the present invention by finding out the following: the composition for preventing soil loss, which comprises the bacillus pasteurii (sporosarcinapasteruurii), has good hardness improving effect compared with the precipitation amount of calcium carbonate under specific urea concentration and calcium concentration; the soil loss prevention method using the same should consider the organic matter content and particle size of the soil in order to achieve a high soil loss prevention rate.

Accordingly, an embodiment of the present invention provides a composition for preventing soil erosion, comprising a culture solution of bacillus pasteurii (Sporosarcina pasteurii), urea and calcium, wherein the urea and calcium are in the same ratio, and the respective concentrations are 1M or less.

Referring to FIG. 1, when the urea concentration is 1500mM, the injected calcium cannot be removed even if mixed with calcium; when the urea to calcium concentration is below 1000mM, the injected calcium is totally removed, and for optimum efficiency, it is preferred that the urea to calcium concentration ratio be 1: 1. More preferably, the urea and calcium concentration is 450mM, as shown in FIG. 2.

Specifically, the Papanicolaou bacillus culture solution is obtained by batch culturing Papanicolaou bacillus in a composition comprising 6g/L urea and 30g/L Tryptic soy broth (Tryptic soy broth) medium, the batch culture being performed at a volume ratio of the composition to the headspace of 1: 7.8 to 1: 8.3, and at 30 ℃, 180rpm for 24 hours. Culture at 180rpm was also possible for 48 hours when the volume ratio of medium composition to headspace was below 1: 7.

The culture solution comprises urea with the concentration of 0.1M (6g/L), and compared with the culture solution comprising urea with high concentration, the culture solution can inhibit the generation of free (fFee) ammonia, and improve the urea hydrolysis rate and the growth rate of the bacillus pasteurianus, thereby improving the precipitation amount of calcium carbonate.

And, the OD value of the pasteuria bacillus culture solution can be 6, and in preparing the soil loss prevention composition of the present invention, the volume of the pasteuria bacillus culture solution is 1/6 of the volume of the soil loss prevention composition, so that the OD value of the composition is 1.

According to another embodiment of the present invention, there is provided a soil-loss prevention method including the steps of: step 1, measuring the organic matter content of soil; and a step 2 of injecting the composition for preventing soil loss according to an embodiment of the present invention into soil, wherein the composition is injected 5 times or more in the step 2 when the organic content of the soil measured in the step 1 is 2.5%; when the content of organic matter is 0%, the composition is injected more than 2 times.

The soil loss prevention method is mainly suitable for the soil with the sandy soil particle size (75-1000 mu m). However, there is a difference in the effect of increasing the hardness in comparison with the amount of precipitated calcium carbonate based on the size of most particles, and therefore, it is necessary to adjust the level of technical applicability, and in particular, as the particle size is smaller, the penetration resistance in comparison with the amount of precipitated calcium carbonate is lower, and thus the number of uses should be increased.

The soil loss in the present invention can be attributed to wind or rainfall, but is not limited thereto.

The soil to which the composition for preventing soil loss and the method for preventing soil loss of the present invention can be applied may be, for example, sand, heavy metal contaminated soil, or the like, but is not limited thereto.

On the one hand, for heavy metal contaminated soil, urea hydrolysis of the bacillus pasteurii can be inhibited by different heavy metal concentrations. Various heavy metals such As Cu, Cd, Pd, Zn, Ni, As, Cr (VI) and the like can exist in the polluted soil, and the enzyme activity can be reduced by the heavy metals existing in a soil solution, soil pore water, soil interstitial water and the like. The urea hydrolysis rate results, measured as the concentration of heavy metals included in the solution, are as follows:

[ Table 1]

* -: there was no statistically significant difference

As shown in table 1, the effect of inhibiting urea hydrolysis of Cu was most remarkable, and urea hydrolysis was severely inhibited when the Cu concentration was increased to 1000 μm or more, making it difficult to apply the soil erosion prevention technique using MICP. Before applying the method for preventing soil loss, the concentration of heavy metals in soil should be confirmed in advance, and the number of times of injection of the composition for preventing soil loss is set in accordance with the effect of inhibiting the hydrolysis rate of urea.

The present invention will be described in more detail with reference to examples. The following examples are intended to illustrate the invention, the scope of which is not limited thereto.

Example 1: preparation of composition for preventing soil loss

Example 1-1: preparation of Bacillus pasteurii culture solution

Triple distilled water was added to Tryptic Soy Broth (TSB) (BD Korea) to make the TSB concentration of the medium composition for culture 30 g/L. Thereafter, autoclaving (autoclaves) was performed at 121 ℃ under 1.45atm for 15 minutes, and the autoclaved medium composition was naturally cooled to 40 ℃ in a clean bench (clean bench). After preparing a urea solution having a concentration of 1M (60g/L) in a volume corresponding to 10% of the volume of the medium composition, the urea solution prepared on a clean bench (clean bench) was filtered through a 0.2 μ M filter and injected into the naturally cooled medium composition to prepare a medium composition having a final urea concentration of 0.1M (6 g/L). After inoculating Bacillus pasteurii (KCTC 3558 strain) into the prepared medium composition, the mixture was put into a batch (batch), and as shown in Table 2 below, the ratio of the medium composition to the headspace volume ("volume ratio") was set to 1: 0, 1: 1.6, 1: 3, 1: 5, 1: 7, 1: 7.8, 1: 8.3, 1: 14, 1: 26, 1: 52, and the culture was performed at 30 ℃ and 30rpm on the side sealed with a lid.

[ Table 2]

The culture time was 48 hours when the volume ratio was 1: 7 or less, and 24 hours when the volume ratio exceeded 1: 7. After completion of the culture, OD of the final medium composition was measured₆₀₀The values and urea hydrolysis ratios are shown in FIG. 11.

As shown in FIG. 11, it was confirmed that the value of 0D was the maximum value at a volume ratio of 1: 7.8; the urea hydrolysis rate is maximum at a volume ratio of 1: 8.3. Therefore, the growth rate and urea hydrolysis rate of the Bacillus pasteurii are most prominent when the volume ratio is 1: 7.8 to 1: 8.3.

According to the above results, after inoculating the Paenibacillus pasteurii solution to the medium composition having urea concentration of 0.1M (6g/L) in 1/100 volume of the medium composition, the volume ratio of the composition to the headspace was set to 1: 8.3, and the mixture was filled in a sealable bottle (bottle) and cultured for 24 hours while stirring at a temperature of 30 ℃, thereby preparing a Paenibacillus pasteurii culture solution. The culture solution was mixed with distilled water at a volume ratio of 1: 2, and the OD value of the mixed culture solution was about 2.

Examples 1 to 2: preparation of a cementation solution

Cementing (cementation) solutions (400, 900, 2000mM) having a concentration 2 times the final target concentration were prepared so that the final urea concentration and calcium concentration of the soil loss prevention composition were 200mM (sample 1), 450mM (sample 2), and 1000mM (sample 3), respectively. The cementation solution is prepared by steaming three timesAdding the distilled water into urea and calcium reagent, completely melting, and adjusting the pH value of the solution. To prepare solutions of each target concentration, the amounts of urea and calcium reagents to be injected per 1L of cementation solution were as follows: 200 mM: urea (urea)24g, calcium (CaCl)₂·2H₂O)59.2 g; 450 mM: 54g of urea (urea) and calcium (CaCl)₂·2H₂O)132.4 g; 1000 mM: 120g of urea (urea) and calcium (CaCl)₂·2H₂O)294 g. The pH of the solution was adjusted by injecting 2N HCl solution or 2N NaOH solution.

The pasteuria cultures and cementation solutions prepared in examples 1-1 and 1-2 were mixed at a ratio of 1: 1 to prepare the final soil erosion prevention composition.

Example 2: determining optimum concentrations of urea and calcium for a soil loss prevention composition

The calcium carbonate concentration (precipitation amount) was measured by injecting 3 soil loss prevention compositions prepared in the example 1 (15 mL of the composition per 50g of the sandy soil at 1 injection) into a test piece prepared by filling sandy soil having a particle size of 150-. Penetration resistance is the hardness of the surface soil measured using a needle penetrometer (needle penetrometer).

As a result, as shown in FIG. 2, the amount of precipitated calcium carbonate increased as the urea concentration and the calcium concentration of the composition increased, but the efficiency of the amount of precipitated calcium with respect to the penetration resistance was the same in sample 1(200mM) and sample 2(450mM), and the efficiency was decreased in sample 3(1000 mM).

From this, it was found that the composition of sample 2 containing 450mM of urea and calcium had a high calcium carbonate precipitation amount per injection and a high penetration resistance with respect to the precipitation amount, and was capable of rapidly forming calcium carbonate in the soil.

Example 3: evaluation of calcium carbonate precipitation amount and penetration resistance based on soil particle size

Example 3-1: amount of precipitated calcium carbonate

A test piece with a height of 2cm was prepared in a cylindrical flask (flask) using sand with a particle size of 75-150 μm, 150-. The composition of sample 2 prepared in example 1 was injected into 4 test pieces (15 mL of the composition per 50g of sand in 1 injection), and the amount of precipitated calcium carbonate after each injection was measured.

As a result, calcium carbonate precipitation occurred in all of the 4 kinds of particle sizes, and the amount of calcium carbonate precipitation was the same based on the injection solution, as shown in FIG. 4.

Example 3-2: penetration resistance to precipitation amount

A test piece having a height of 2cm was prepared in a cylindrical flask (bottle) using sand having a particle size of 75 to 150 μm, 150-.

Referring to fig. 3, the amount of calcium carbonate precipitation increased with the increase of the number of injections, and it was confirmed that the soil hardness could be enhanced only by calcium carbonate forming Effective bridge by maintaining 25N/mm for the penetration resistance when the number of injections was 7 or more. Also, as shown in fig. 4, the smaller the soil particle size, the lower the penetration resistance against the amount of precipitated calcium carbonate. Based on the above test results, when the soil erosion prevention method of the present invention is used, the number of times of injection of the composition should be increased for soil having a small particle size.

Example 4: calcium carbonate precipitation and penetration resistance evaluation based on soil organic matter content

A test piece having a height of 2cm was prepared by mixing sand and Peat (Peat) having a particle size of 150-. Test pieces with organic matter contents of 0%, 1%, 2.5% and 5% were prepared by using different mixing ratios of Peat (Peat) and sand. The composition of sample 2 prepared in example 1 was injected into 4 test pieces (15 mL of the composition per 50g of sand in 1 injection), and the amount of calcium carbonate precipitation per injection and the penetration resistance to the amount of calcium carbonate precipitation were measured.

As a result, as shown in FIG. 5, calcium carbonate precipitation occurred in all of the 4 kinds of peat (peat), and the amount of calcium carbonate precipitation was similar based on the injected solution. As for the penetration resistance, as shown in fig. 5, the higher the organic matter content is, the lower the penetration resistance is for the same amount of precipitated calcium carbonate because the organic matter contained in the soil hinders the growth of calcium carbonate crystals.

Example 5: evaluation of effect of preventing soil loss based on wind and rainfall

Example 5-1: preparation of a plate-shaped test piece

Sandy soil (Sand, organic matter content 0%) and Loamy sandy soil (Loamy Sand, organic matter content 2.6%) were prepared, and the soil was loaded on plates of 30cm x 30cm and 20cm x 20cm, respectively, to prepare plate-like test pieces.

The composition of sample 2 prepared in example 1 was sprayed onto a plate-like test piece, and sandy soil test pieces were sprayed 1, 2, 3, 4, 5 times; and spraying loam sandy soil test pieces for 1, 3, 5, 7 and 8 times, and observing whether the soil is condensed. As a result, as shown in fig. 6 and 7, when the sandy soil was sprayed 2 times, the aggregation of the loamy sandy soil was observed when the sandy soil was sprayed 5 times, and the aggregated soil was not dispersed in water.

Example 5-2: effect of preventing soil loss due to rainfall-subject to test piece

The composition of sample 2 prepared in example 1 was sprayed on the sandy soil and loam test pieces with a plate size of 20cm × 20cm prepared in example 5-1, and 0, 1, 2, 3, 4, 5 times (sandy soil) and 0, 1, 3, 5, 7, 8 times (loam) were sprayed on the surface, respectively. The results of measuring the amount of soil lost in the inclined direction at rainfall intensities of 13.5mm/hr, 33mm/hr, and 75mm/hr and inclination conditions of 5.1 °, 8.5 °, and 15 ° for the test piece to which MICP was applied are shown in FIGS. 8 and 9.

As shown in fig. 8, the sandy soil test piece showed the effect of preventing the soil loss due to rainfall from 2 injections, and as shown in fig. 9, the loamy sandy soil test piece showed the effect of preventing the soil loss due to rainfall from 5 injections. The same results as in example 4 were obtained because the loamy sandy soil had a higher organic content.

Thereafter, the effect of preventing soil loss due to rainfall was evaluated. The loss reduction rate was calculated using the following formula, and the results are shown in Table 3.

[ Table 3]

As shown in Table 3, the loss reduction rate of sandy soil is higher than that of loamy sandy soil, and under the conditions of the inclination of more than 8.5 degrees and the rainfall intensity of 33mm/hr and 75mm/hr, the loss reduction rate of loamy sandy soil is 64-73%; the loss reduction rate of the sandy soil is 70-90%.

Examples 5 to 3: prevention effect of soil loss due to rainfall-targeting on-site soil

The results of collecting 3 kinds of soil from the surface of the heavy metal contaminated soil and analyzing the soil characteristics (organic matter content, CEC, soil property) and the total content concentration (US EPA 3052) are shown in tables 4 and 5.

[ Table 4]

[ Table 5]

From the measurement results, the composition of sample 2 prepared in example 1 was injected into the

soil

1, 2 and 35 times, 3 times and 4 times, respectively, in consideration of the organic matter content, and then the runoff reduction rate was derived under the rainfall conditions of 8.5 ° and 33 mm/hr. As a result, as shown in fig. 10, the soil loss reduction rates of the soils 1 to 3 were 56%, 69%, and 82%, respectively, and the soil loss due to rainfall was effectively prevented for the solid soil.

In summary, the embodiments have been described with limited reference to the accompanying drawings, and those skilled in the art will be able to make various modifications and variations based on the description. For example, the techniques described may be performed in a different order than the methods described, and/or components of systems, structures, devices, circuits, etc. described may be combined or combined in a different manner than the methods described, or may be replaced or substituted with other components or equivalents thereof, to achieve suitable results.

Accordingly, other embodiments, other examples, and equivalents of the scope of the claims, are intended to fall within the scope of the claims.

Claims

1. A composition for preventing soil loss comprising:

a bacillus pasteurii culture solution, urea and calcium,

the urea and calcium are in the same ratio, and the respective concentrations are 1M or less.

2. The composition for preventing soil loss according to claim 1,

the concentration of the urea and the calcium is 450 mM.

3. The composition for preventing soil loss according to claim 1,

the pasteuria bacillus culture solution is pasteuria bacillus cultured in batch in a composition comprising 6g/L urea and 30g/L pancreatin soybean broth culture medium,

the volume ratio of the composition to the headspace of the batch culture is 1: 7.8 to 1: 8.3, and is performed at 180rpm at 30 ℃ for 24 hours.

4. The composition for preventing soil loss according to claim 1,

the 0D value of the pasteuria bacillus culture solution is 6.

5. The composition for preventing soil loss according to claim 1,

the volume of the pasteuria bacillus culture was 1/6 of the volume of the soil loss prevention composition.

6. A method of preventing soil loss comprising the steps of:

step 1, measuring the organic matter content of soil;

step 2 of injecting the soil loss prevention composition according to any one of claims 1 to 5 into soil,

in the step 2, when the organic matter content of the soil measured in the step 1 is 2.5% or more, injecting the composition 5 times or more; when the content of organic matter is 0%, the composition is injected more than 2 times.

7. The method for preventing soil loss according to claim 6,

the particle size of the soil is 75 μm to 1000 μm.

8. The method for preventing soil loss according to claim 6,

the soil loss is due to rainfall.

9. The method for preventing soil loss according to claim 6,

the soil is heavy metal contaminated soil.