CN110947754A - Method for restoring farmland soil polluted by DDTs by using plant-reinforced microorganisms - Google Patents

Abstract

A method for restoring farmland soil polluted by DDTs by plant-reinforced microorganisms relates to a method for restoring the polluted farmland soil, and is characterized in that celery is planted on the basis of adding DDTs efficient degrading bacteria DC-1, the DDTs in the soil are efficiently degraded by the degrading bacteria DC-1, meanwhile, root exudates of the celery in the growth process can provide a good living environment for the microorganisms, the activity and the quantity of the microorganisms are improved, the DDTs efficient degrading bacteria can be activated and strengthened, and the DDTs in the soil can be absorbed, converted, decomposed and the like in the microbial metabolism process, so that the restoration of the farmland soil polluted by the DDTs is realized. The repairing method provided by the invention has the characteristics of low repairing cost, simplicity and convenience in operation and large-area popularization, and meanwhile, the quality and the yield of celery are not obviously influenced in the repairing process, and the aim of repairing while producing can be realized.

Description

Method for restoring farmland soil polluted by DDTs by using plant-reinforced microorganisms

Technical Field

The invention relates to a method for restoring polluted farmland soil, in particular to a method for restoring DDTs polluted farmland soil by using plant-reinforced microorganisms.

Background

With the development of social economy, people's environmental awareness is continuously strengthened, and people's demand for safe agricultural products is continuously increased. Meanwhile, China is a country with less per capita cultivated land area, and limited cultivated lands are influenced by various pollutants discharged by chemical fertilizers, pesticides and industrial and agricultural production, so that farmland soil is polluted to different degrees, and the soil environment quality is reduced. Among them, DDTs have serious harm to human health and environment due to their long-term residue, semi-volatility and high toxicity, and organic pollutants which have been prioritized and reduced by numerous international organizations and countries may enter human bodies through agricultural crops, causing food safety problems and causing harm to human bodies. With the development of social economy, people's awareness of environmental protection is continuously strengthened, and people's demand for safe agricultural products is continuously increased. The contradiction between the increasing demand of people and the continuous decline of the soil environment quality is continuously outstanding, people and governments pay general attention to the method, and a safe, reliable, high-quality and low-cost method which does not influence normal agricultural production and repairs the polluted farmland soil while producing is urgently needed to be found.

Disclosure of Invention

The invention aims to provide a method for restoring soil of a farmland polluted by DDTs by using plant-reinforced microorganisms, and relates to an in-situ restoration method for restoring the soil of the farmland polluted by DDTs by using celery-reinforced efficient degrading bacteria. Adding high-efficiency degrading bacteria, namely arthrobacter globiformis, into the soil of the farmland polluted by the DDTs, then planting celery, and utilizing the activation and enhancement effects of the celery on the high-efficiency degrading bacteria to fulfill the aim of restoring the DDTs in the soil of the farmland while producing.

The purpose of the invention is realized by the following technical scheme:

a method for restoring farmland soil polluted by DDTs by using plant-enhanced microorganisms comprises the following operation processes:

(1) preparing high-efficiency degrading bacterium liquid: inoculating Arthrobacter globiformis (Arthrobacter globiformis) into LB liquid culture medium, culturing at 30 deg.C and 100 rpm in a shaking table at constant temperature until the bacterial liquid concentration is 1.0 × 10⁸-10¹⁰CFU·mL^-1Then, obtaining high-efficiency degradation bacterial liquid for later use;

(2) celery cultivation: culturing parsley seedlings in a greenhouse in advance, and reserving when the parsley seedlings grow to be about 8-9cm high;

(3) and (3) repairing process:

leveling the contaminated farmland soil to be restored, uniformly spraying the prepared high-efficiency degrading bacteria liquid to the farmland soil according to the proportion of 500mL per square meter, turning the farmland soil with the depth of 0-20cm, enabling the degrading bacteria to be uniformly distributed in the soil to be restored as much as possible, and then transplanting the cultivated celery seedlings, wherein the plant spacing and the row spacing are both 4-5 cm; the water content of the soil is kept to be 30% of the maximum field water capacity, and in order to improve and ensure the remediation efficiency, the temperature of the soil can be kept to be 25-30 ℃ by using a greenhouse or plastic film mulching mode; after three months of remediation, collecting a soil sample after remediation, determining the concentration of DDTs in the soil sample, and if the concentration of DDTs does not reach the remediation target, performing remediation for multiple times until the DDTs in the farmland soil reaches the soil environment safety standard.

The method for restoring farmland soil polluted by DDTs by using plant enhanced microorganisms comprises the step of preparing celery into parsley (celery)Libanotis seseloides (Fisch. & C. A. Mey. ex Turcz.) Turcz.）。

The invention has the advantages and effects that:

the invention firstly uses the parsley reinforced high-efficiency degrading bacterium arthrobacterium globosum to repair the soil of the farmland polluted by the DDTs, and is an in-situ repair method for repairing the soil of the farmland polluted by the DDTs. The method utilizes the efficient degradation effect of the degrading bacteria on the DDTs in the farmland soil, and simultaneously plants celery, so that the activity of the efficient degrading bacteria is enhanced, the microbial quantity is increased, the degrading bacteria are activated and enhanced, and the efficient remediation of the DDTs-polluted farmland soil is realized. The repairing method has the advantages of low cost, simple and convenient operation, no use of chemical agents, safe repairing process, no obvious influence on celery quality and yield in the process of repairing DDTs, realization of the aim of repairing while producing, and large-area popularization.

Drawings

FIG. 1 is a schematic diagram of an in-situ remediation method for remediating DDTs contaminated farmland soil by using celery enhanced efficient degrading bacteria DC-1;

FIG. 2 shows the average repairing efficiency of DDTs in the blank control group, the celery enhanced high-efficiency degrading bacteria and the experiment group only adding the high-efficiency degrading bacteria.

Detailed Description

The present invention will be described in detail with reference to the embodiments shown in the drawings.

The invention relates to a method for restoring farmland soil polluted by DDTs (dichloro-diphenyl-trichloroethane) by using plant-enhanced microorganisms, which adopts an in-situ restoration mode for the farmland soil polluted by the DDTs, and the high-efficiency degrading bacteria used in the polluted soil are arthrobacter globiformis (Arthrobacter globiformis)Arthrobacter globiformis) Wherein the concentration of the bacterial liquid is 1.0 multiplied by 10⁸-10¹⁰CFU·mL^-1The celery used is parsley (Libanotis seseloides (Fisch. & C. A. Mey. ex Turcz.) Turcz.) (ii) a Uniformly spraying the prepared high-efficiency degradation bacterium liquid in surface farmland soil of 0-20cm according to the proportion of 500mL per square meter, and uniformly mixing; adding degrading bacteria, transplanting into the celery seedlings cultivated in advance, wherein the plant spacing and the row spacing are 4-5cm, watering regularly during the growth period of the celery to ensure that the water content of the soil is kept at 30% of the maximum water holding capacity of the field, and the growth period is 3 months. And (4) measuring the concentration of the DDTs in the soil after repairing, and repeating the process until the concentration reaches the corresponding standard if the concentration does not reach the soil environment safety standard.

Arthrobacter globiformis (Arthrobacter globiformis), deposited at the China general microbiological culture Collection center on 3, 16 th month in 2016, with the collection number: CGMCC No.12220, preservation Address: xilu No.1 Hospital No. 3, Beijing, Chaoyang, North.

Example 1

The laboratory simulation experiment was as follows:

(1) preparing high-efficiency degradation bacterial liquid: inoculating active high-efficiency degrading bacterium Arthrobacter globiformis (Arthrobacter globiformis) into LB liquid culture medium, culturing at 30 deg.C and constant temperature in a shaker at 100 rpm until the concentration of the bacterium liquid is 1.0 × 10⁸-10¹⁰CFU·mL^-1And then obtaining the high-efficiency degradation bacterial liquid for later use.

(2) Celery cultivation: and (4) cultivating the celery seedlings in a greenhouse in advance, and reserving the celery seedlings when the celery seedlings grow to be about 8-9cm high.

(3) And (3) repairing process:

collecting DDTs polluted farmland soil, removing stones and impurities, uniformly mixing after passing through a 2mm sieve, putting the soil into a flowerpot to enable the soil depth to be 20cm, and determining the physical and chemical properties of the soil as follows: the organic content is 54.37 g.kg^-1The cation exchange capacity was 13.09cmol kg^-1The pH value is 7.17, and the proportion of clay, powder and sand is respectively 26.11%, 72.82% and 1.07%. Uniformly spraying the prepared degrading bacteria liquid according to the proportion of 500mL per square meter, and turning and uniformly mixing farmland soil with the depth of 0-20 cm. Transplanting into the celery seedlings cultivated in advance, wherein the plant spacing and the row spacing are both 4-5cm, the water content is kept at 30% of the maximum water holding capacity in the field, and the indoor temperature is kept at 25-30 ℃. Meanwhile, a blank group, a control experiment group only added with efficient degrading bacteria and only planted with celery are set. Soil samples before and 3 months after remediation were collected to determine the content of DDTs and the plant weight of celery in the soil. The plant weight of the experimental group for planting celery and the celery intensified high-efficiency degrading bacteria is 69.46 +/-3.21 g and 65.89 +/-6.42 g, and the plant weight is not changed obviously. The average repairing efficiency of DDTs in the blank control group, the celery enhanced high-efficiency degrading bacteria and the experiment group only adding the high-efficiency degrading bacteria is shown in figure 2. As can be seen from FIG. 2, compared with the blank control group, the average repair efficiency of the enhanced efficient degradation bacteria of celery and the DDTs of the experimental group only added with the efficient degradation bacteria is significantly improved. Average repairing efficiency of DDTs in experimental group only adding efficient degrading bacteria44.68 percent and 60.50 percent of celery reinforced high-efficiency degradation bacterium group, so that the celery can obviously improve the repairing efficiency of the high-efficiency degradation bacterium on DDTs in soil.

Claims (2)

1. A method for restoring farmland soil polluted by DDTs by using plant-enhanced microorganisms is characterized by comprising the following operation processes:

(1) preparing high-efficiency degrading bacterium liquid: inoculating Arthrobacter globiformis (Arthrobacter globiformis) into LB liquid culture medium, culturing at 30 deg.C and 100 rpm in a shaking table at constant temperature until the bacterial liquid concentration is 1.0 × 10⁸-10¹⁰CFU·mL^-1Then, obtaining high-efficiency degradation bacterial liquid for later use;

(2) celery cultivation: culturing parsley seedlings in a greenhouse in advance, and reserving when the parsley seedlings grow to be about 8-9cm high;

(3) and (3) repairing process:

leveling the contaminated farmland soil to be restored, uniformly spraying the prepared high-efficiency degrading bacteria liquid to the farmland soil according to the proportion of 500mL per square meter, turning the farmland soil with the depth of 0-20cm, enabling the degrading bacteria to be uniformly distributed in the soil to be restored as much as possible, and then transplanting the cultivated celery seedlings, wherein the plant spacing and the row spacing are both 4-5 cm; the water content of the soil is kept to be 30% of the maximum field water capacity, and in order to improve and ensure the remediation efficiency, the temperature of the soil can be kept to be 25-30 ℃ by using a greenhouse or plastic film mulching mode; after three months of remediation, collecting a soil sample after remediation, determining the concentration of DDTs in the soil sample, and if the concentration of DDTs does not reach the remediation target, performing remediation for multiple times until the DDTs in the farmland soil reaches the soil environment safety standard.

2. The method for phytoenhancement and microbial remediation of farmland soil contaminated with DDTs as claimed in claim 1, wherein said celery used is parsley (celery)Libanotis seseloides (Fisch. & C. A. Mey. ex Turcz.) Turcz.）。

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