Method for repairing continuous cropping obstacle hardened soil through smoldering technology

Abstract

The invention discloses a method for repairing continuous cropping obstacle hardened soil by adopting a smoldering technology, and belongs to the field of solid waste resource utilization and agricultural production. The method for repairing the continuous cropping obstacle hardened soil through the smoldering technology comprises the steps that agriculture and forestry solid waste generated by farming crops serves as fuel, the fuel is smoldered in the continuous cropping obstacle hardened soil, after smoldering is completed, after the soil is completely cooled, a healthy soil biological agent is added, and soil preparation is conducted; and uniformly mixing the soil, the smoldering product and the healthy soil biological agent, and maintaining the soil moist for 7-15 days to complete the remediation of the continuous cropping obstacle hardened soil. The method is easy to operate and low in treatment cost, the soil property can be remarkably improved, and the agricultural yield is increased. The method provided by the invention not only can solve the treatment problem of agriculture and forestry solid wastes, but also can provide a novel cheap and feasible solution for the hardening problem of continuous cropping obstacle soil, realizes the cyclic utilization of resources, and has a wide development prospect.

Description

Technical Field

[0001] The invention belongs to the field of solid waste resource utilization and agricultural production, and specifically relates to a method for repairing compacted soil caused by continuous cropping obstacles by adopting smoldering technology. Background Art

[0002] With the advancement of agricultural modernization, facility agriculture has flourished, the degree of intensive land use has continued to increase, and continuous cropping has become more and more common. However, long-term continuous cropping and the large-scale use of chemical fertilizers and pesticides have gradually caused problems of continuous cropping obstacles and soil compaction. On the one hand, continuous cropping obstacles lead to poor crop growth and development, increased pests and diseases, and reduced yields and quality, seriously affecting the economic benefits of agriculture. On the other hand, soil compaction deteriorates the physical properties of the soil, reduces porosity, deteriorates permeability, and lowers ground temperature, hindering the development of crop roots, affecting their absorption of water and nutrients, and thus restricting the sustainable development of agriculture. Faced with this grim situation, research on continuous cropping obstacles and compaction is urgent in order to explore effective solutions to ensure the stability of agricultural production and the health of the ecological environment.

[0003] In the context of global resource shortage and great pressure on the ecological environment, the resource treatment of agricultural and forestry solid waste is particularly important. With the continuous development of agricultural and forestry production, a large amount of agricultural and forestry solid waste such as crop straw, fruit tree branches, and wood processing residues is constantly generated. For a long time, most of these solid wastes have been incinerated or discarded at will, which not only caused a huge waste of resources, but also caused serious problems such as air pollution, soil damage and fire hazards. At the same time, as people's understanding of sustainable development continues to improve, the demand for efficient use of resources and environmental protection is becoming increasingly strong. Therefore, conducting research on the resource treatment of agricultural and forestry solid waste and converting it into valuable resources, such as biofuels, organic fertilizers, biomass materials, etc., can not only reduce the negative impact on the environment, but also realize the recycling of resources, and provide strong support for the sustainable development of agriculture and forestry. However, the transportation cost has led to its large-scale accumulation in the fields, so the original treatment and disposal technology of agricultural and forestry solid waste needs to be studied.

[0004] At present, scientific researchers have developed a variety of green and effective biological control methods based on the important factors of continuous cropping obstacles, mainly through the development of biological agents, organic fertilizers, soil strong reduction measures and phage therapy to prevent and control continuous cropping obstacles. However, these methods generally have the problems of high material and equipment investment costs, long time consumption and low efficiency, which are not conducive to large-scale promotion and application. The current in-situ treatment technology of agricultural and forestry solid waste is mainly to prepare biochar, and add biochar to the soil to improve the soil condition, but it faces high costs and is prone to air pollution. How to effectively combine the resource treatment of agricultural and forestry solid waste with soil problems while avoiding the generation of secondary pollution is a new challenge facing researchers. Summary of the invention

[0005] In response to the above technical problems, the present invention provides an efficient and low-cost method for repairing soil compaction caused by continuous cropping obstacles, which effectively combines the resource treatment of agricultural and forestry solid waste with soil repair methods, and provides a new way for the resource utilization of agricultural and forestry solid waste.

[0006] The technical solution adopted by the present invention to solve its technical problem is: a method for repairing soil compaction caused by continuous cropping obstacles by using smoldering technology: using agricultural and forestry solid waste generated by agricultural crops as fuel, causing the fuel to smolder in the soil compaction caused by continuous cropping obstacles, waiting for the soil to completely cool after the smoldering is completed, and then adding healthy soil biological bacteria agents and performing soil preparation, so that the soil, smoldering products, and healthy soil biological bacteria agents are evenly mixed, and the soil is kept moist for 7 to 15 days, thereby completing the repair of the soil compaction caused by continuous cropping obstacles.

[0007] In the above method, the continuous cropping barrier compacted soil is any one of nutrient element loss soil, acidic soil, saline-alkali soil, rocky desertification soil and sandy soil.

[0008] In the above method, the agricultural and forestry solid waste generated by agricultural crops is at least one of corn stalks, bean stalks, pine needles, sunflower stalks, dead grass, tobacco stalks and dead branches and leaves.

[0009] In the above method, the healthy soil biological agent is any one of forest soil, organic fertilizer, activated sludge and EM agent.

[0010] The above method of repairing soil compaction caused by continuous cropping obstacles by using smoldering technology specifically comprises the following steps:

[0011] A. Loosen the soil compacted by continuous cropping and pile it in strips and ridges to reduce the soil moisture content through natural drying;

[0012] B. Dry and crush the agricultural and forestry solid waste generated by agricultural crops, and evenly pile the crushed agricultural and forestry solid waste in the ridge ditch at a mass ratio of 1:1 to 3 between agricultural and forestry solid waste and soil;

[0013] C. Ignite agricultural and forestry solid waste, wait for it to burn for 0.5 to 2 minutes, cover it with a layer of loose soil to extinguish the open flame, and let it smolder;

[0014] D. After the agricultural and forestry solid waste is completely burned, wait for the soil to cool down completely, then add 0.1% to 0.5% of healthy soil biological bacteria agent to mix the soil, smoldering products and healthy soil biological bacteria agent evenly, keep the soil moist and maintain for 7 to 15 days to complete the repair of soil compaction caused by continuous cropping obstacles.

[0015] Furthermore, in the above step A, the moisture content of the soil compacted due to continuous cropping obstacles is 10% to 30%.

[0016] Furthermore, in the above step B, the moisture content of the crushed agricultural and forestry solid waste is less than 10%.

[0017] Furthermore, in the above step C, a layer of 3 to 10 cm of ridge soil is evenly covered.

[0018] Furthermore, in the above step D, the soil moisture content is maintained at 10-30%.

[0019] The carbon content of the soil in the continuous cropping obstacle repaired by the above method is more than 20%, the N content is 0.4% to 0.6%, the P content is 0.9% to 1.3%, the K content is 3.8% to 4.2%, and the soil density is 3.1 to 4.6 g / cm 3 , water retention rate>80%.

[0020] The beneficial effects of the present invention are as follows: in the traditional planting process, most of them are ridge planting, and all need to be turned over and air-dried; the method of the present invention directly utilizes the soil morphology of the traditional planting mode, controls the soil moisture content by natural drying, reduces the manpower and material effects of the preliminary preparation process, and reduces the construction cost; the present invention is to naturally dry the agricultural and forestry solid waste generated in the planting process, crush it on the spot and place it in the ridge ditch, cover the soil on the ridge on its surface after ignition, extinguish its open fire, and make the agricultural and forestry solid waste in a smoldering state, the heat generated by the smoldering will kill the pests hidden in the soil, and the biochar generated by the smoldering will supplement the soil with carbon, increase the carbon content of the soil, and provide conditions for the attachment of microorganisms and the maintenance of nutrients; at the same time, the smoldering can release the plant-usable state elements in the compacted soil and agricultural and forestry solid waste, and improve the soil vitality; by adding healthy soil microorganisms, the soil microecological reconstruction is realized after long-term cultivation. The method of the present invention does not require complex equipment, nor does it use expensive reagents, so as to realize the in-situ disposal of agricultural and forestry solid waste, and at the same time reduce the cost of managing the compacted soil of continuous cropping obstacles.

[0021] From an environmental protection perspective: this method does not produce secondary pollution. During the smoldering process of agricultural and forestry solid waste, the fly ash, NOx, SO2, VOCs and other gas components in the flue gas generated will be adsorbed and captured by soil colloids, providing the soil with necessary nutrients, achieving flue gas treatment while providing the soil with the elements needed for crop growth.

[0022] From the perspective of sustainable development: This method has important strategic significance. On the one hand, this method can realize the resource utilization of agriculture and forestry, reduce pollution to the environment, and meet the strategic requirements of national sustainable development. On the other hand, this method can significantly control the soil compaction caused by the long-term application of fertilizers and pesticides, and improve the development of agriculture. The by-products produced by smoldering provide nutrients for agricultural production and realize the recycling of resources. In addition, this method can also drive the development of related industries, such as agricultural and forestry solid waste treatment industry and agriculture, and create more employment opportunities and economic benefits.

[0023] The method of the present invention uses local materials, is simple to operate, and can be used to treat the soil during the process of agricultural land management, greatly reducing the cost of treatment; the porosity and water retention rate of the compacted soil treated by the method are significantly increased, and the introduction of biochar improves the fertility of the soil, which can significantly increase the seed germination rate and increase agricultural output; the method realizes the treatment of agricultural and forestry solid waste while preventing the soil from being compacted due to continuous cropping obstacles, which affects the yield of grain crops; during the smoldering treatment process, the gaseous pollutants generated by the smoldering are filtered through the soil, reducing the risk of environmental pollution. The method of the present invention can not only solve the problem of treating agricultural and forestry solid waste, but also provide a new, cheap and feasible solution to the problem of soil compaction caused by continuous cropping obstacles, realize the recycling of resources, and has broad development prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a flow chart of a method for repairing soil compaction caused by continuous cropping using smoldering technology according to the present invention;

[0025] Figure 2 This is the comparison result before and after the treatment of typical continuous cropping obstacle soil in implementation case 1;

[0026] Figure 3 Comparison results before and after the rocky desertification soil treatment for implementation case 2;

[0027] Figure 4 This is the comparison result before and after the saline-alkali soil treatment in implementation case 3. DETAILED DESCRIPTION

[0028] The technical solution of the present invention can be specifically implemented in the following manner.

[0029] The present invention provides a method for treating the smoldering of soil compacted by continuous cropping. The specific process is as follows: Figure 1 As shown. The main steps of the method are: first, loosen the compacted soil, pile the soil in strip-chopped ridges, and keep the moisture content at 10% to 30% through natural drying; dry the agricultural and forestry solid waste, reduce its moisture content to less than 10%, and crush it; secondly, put the crushed agricultural and forestry solid waste in the ridge ditch according to the mass ratio of 1:1 to 3 with the soil, and ignite it with an open flame; after the ignited agricultural and forestry solid waste burns for 0.5 to 2 minutes, cover 3 to 10 cm of soil on the ridge, extinguish the open flame, and keep the soil loose; finally, after the agricultural and forestry solid waste is completely burned out and completely cooled, add 0.1% to 0.5% healthy soil biological bacteria agent, fully mix the generated ash, biochar and covering soil, keep the moisture content at 10% to 30%, and plant it after idle maintenance for 7 to 15 days, so as to realize the ecological reconstruction of the compacted soil with continuous cropping obstacles.

[0030] The technical solution and effects of the present invention are further illustrated below through practical examples.

[0031] Example

[0032] Example 1

[0033] 1. Treatment of soil compaction caused by continuous cropping

[0034] (1) Pretreatment of compacted soil and agricultural and forestry solid waste caused by continuous cropping: First, loosen the compacted soil, pile the soil in strips and ridges, and keep the moisture content at 10% to 30% through natural drying; dry the agricultural and forestry solid waste to reduce its moisture content to less than 10%, and crush it; then place the crushed agricultural and forestry solid waste in the ridge ditch at a ratio of 1:1 to 3 with the soil, and ignite it with an open flame; the specific process is shown in Table 1.

[0035] Table 1 Pretreatment process

[0036] Example 1 Example 2 Example 3 Soil Type Typical continuous cropping obstacle soil Rocky desert soil Saline soil Moisture content 10％ 20％ 30％ Biomass Type Corn stalks Pine Needles Cigarette rod Moisture content 10％ 5％ 3％ Ratio 1：3 1：1 1：2

[0037] (2) Smoldering: After the ignited agricultural and forestry solid waste burns for 0.5 to 2 minutes, it is covered with 3 to 10 cm of soil on the ridge to extinguish the open flame and keep the soil loose. The specific process is shown in Table 2.

[0038] Table 2 Smoldering process

[0039] Ignition time Soil cover thickness Example 1 0.5min 10cm Example 2 2min 3cm Example 3 1min 6cm

[0040] (3) Microecological reconstruction: After the agricultural and forestry solid waste is completely burned and cooled down, add 0.1% to 0.5% healthy soil biological agent, mix the generated ash, biochar and topsoil thoroughly, keep the moisture content at 10% to 30%, and leave it idle for 7 to 15 days before planting. The specific process is shown in Table 3.

[0041] Table 3 Microecological reconstruction

[0042] Example 1 Example 2 Example 3 Types of healthy soil organisms Understory soil Organic Fertilizer EM bacteria agent Amount of microbial agent added 0.1％ 0.5％ 0.2％ Moisture content 10％ 20％ 30％ Idle time 7d 15d 10d

[0043] 2. Performance test of treated soil

[0044] Example 1 Typical continuous cropping obstacle soil smoldering treatment soil test results are as follows Figure 2As shown in the figure, it can be seen that the color of the soil with continuous cropping obstacles has obviously changed to brown after treatment, and the content of granular soil is relatively high. Through testing, it was found that the carbon content after treatment was 30%, which was about 20% higher than before treatment; the water retention rate after treatment was 80%, which was 50% higher than before treatment; the soil density was 3.1g / cm3, the N content was 0.5%, the P content was 0.9%, and the K content was 3.8%; the seed germination rate after treatment was 92%, which was 47% higher than before treatment. It can be seen that the treatment method of the present invention significantly improves the properties of the soil with continuous cropping obstacles and increases the nutrients in the soil.

[0045] Example 2 The test results of the soil after the rocky desertification soil smoldering treatment are as follows Figure 3 As shown in the figure, it can be seen that after treatment, the rocky desertification soil changes from gray dispersed sandy soil to brown granular soil. From the appearance, the treatment method can improve the soil structure. Through testing, it was found that the carbon content after treatment was 35%, which was about 30% higher than before treatment; the water retention rate after treatment was 91%, which was 57% higher than before treatment; the soil density was 4.6g / cm3, the N content was 0.6%, the P content was 1.3%, and the K content was 4.2%; the seed germination rate after treatment was 95%, which was 65% higher than before treatment. It can be seen that the treatment method of the present invention also has a significant improvement effect on the treatment of rocky desertification soil.

[0046] Example 3 The test results of the soil after the smoldering treatment of saline-alkali soil are as follows Figure 4 As shown in the figure, it can be seen that the treated saline-alkali soil has changed from gray to granular black. Through testing, it was found that the carbon content after treatment was 41%, which was about 25% higher than before treatment; the water retention rate after treatment was 96%, which was 36% higher than before treatment; the soil density was 4.0g / cm3, the N content was 0.4%, the P content was 1.2%, and the K content was 4.1%; the seed germination rate after treatment was 98%, which was 37% higher than before treatment. It can be seen that the saline-alkali soil treated by the method of the present invention meets the standard of healthy soil.

Claims

1. A method for repairing soil compaction caused by continuous cropping using smoldering technology, characterized in that: Use agricultural and forestry solid waste produced by cultivated crops as fuel, and let the fuel smolder in the compacted soil caused by continuous cropping. After the smoldering is completed, wait for the soil to cool completely, then add healthy soil biological bacteria agent and organize the soil to make the soil, smoldering products, and healthy soil biological bacteria agent evenly mixed. Keep the soil moist and leave it idle for 7 to 15 days to complete the repair of the compacted soil caused by continuous cropping.

2. The method for repairing soil compaction caused by continuous cropping using smoldering technology according to claim 1, characterized in that: The soil compacted by continuous cropping obstacles is any one of the soils with nutrient loss, acidic soil, saline-alkali soil, rocky desertification soil and sandy soil.

3. The method for repairing soil compaction caused by continuous cropping using smoldering technology according to claim 1, characterized in that: The agricultural and forestry solid waste generated by agricultural crops is at least one of corn stalks, bean stalks, pine needles, sunflower stalks, dead grass, tobacco stalks and dead branches and leaves.

4. The method for repairing soil compaction caused by continuous cropping using smoldering technology according to claim 1, characterized in that: The healthy soil biological agent is any one of forest soil, organic fertilizer, activated sludge and EM agent.

5. The method for repairing soil compaction caused by continuous cropping using smoldering technology according to any one of claims 1 to 4, characterized in that: The specific steps include: A. Loosen the soil compacted by continuous cropping and pile it in strips and ridges to reduce the soil moisture content through natural drying; B. Dry and crush the agricultural and forestry solid waste generated by agricultural crops, and evenly pile the crushed agricultural and forestry solid waste in the ridge ditch at a mass ratio of 1:1 to 3 between agricultural and forestry solid waste and soil; C. Ignite agricultural and forestry solid waste, wait for it to burn for 0.5 to 2 minutes, cover it with a layer of loose soil to extinguish the open flame, and let it smolder; D. After the agricultural and forestry solid waste is completely burned, wait for the soil to cool down completely, then add 0.1% to 0.5% of healthy soil biological bacteria agent to mix the soil, smoldering products and healthy soil biological bacteria agent evenly, keep the soil moist, and after 7 to 15 days of idleness, the repair of soil compaction caused by continuous cropping obstacles will be completed.

6. The method for repairing soil compaction caused by continuous cropping using smoldering technology according to claim 5, characterized in that: In step A, the moisture content of the soil compacted by continuous cropping is 10% to 30%.

7. The method for repairing soil compaction caused by continuous cropping using smoldering technology according to claim 5, characterized in that: In step B, the moisture content of the crushed agricultural and forestry solid waste is less than 10%.

8. The method for repairing soil compaction caused by continuous cropping using smoldering technology according to claim 5, characterized in that: In step C, a 3-10 cm layer of ridge soil is evenly covered.

9. The method for repairing soil compaction caused by continuous cropping using smoldering technology according to claim 5, characterized in that: In step D, the soil moisture content is maintained at 10-30%.

10. The method for repairing soil compaction caused by continuous cropping using smoldering technology according to any one of claims 1 to 9, characterized in that: The carbon content of the repaired soil is >20%, the N content is 0.4%-0.6%, the P content is 0.9%-1.3%, the K content is 3.8%-4.2%, and the soil density is 3.1-4.6 g / cm 3 , water retention rate>80%.

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