Method for studying the regulation mechanism of micro-nano bubble water coupled with gamma-polyglutamic acid on soil cracks

Abstract

The present application relates to a method for studying the regulation mechanism of micro-nano bubble water coupled with gamma-polyglutamic acid on soil fissures, belonging to the technical field of soil improvement. The method comprises the following steps: S1: collecting and pretreating soil samples; S2: uniformly mixing gamma-polyglutamic acid solution with soil samples; S3: layering the mixed soil into containers and compacting to a preset bulk density; S4: slowly spraying and irrigating the soil with micro-nano bubble water; S5: after the saturated soil is left to stand for a predetermined time, it is placed in a preset temperature and humidity environment for dry-wet cycle treatment; S6: coupling parameter optimization, using an improved ant colony algorithm to generate an initial solution, and introducing a carbon emission factor as heuristic information to optimize the path selection probability formula. The present application can clearly regulate the regulation law of micro-nano bubble water coupled with gamma-polyglutamic acid on soil fissures, screen the optimal coupling parameter combination with low carbon adaptability, and take into account the regulation effect, ecological environmental protection and low carbon demand, thereby providing scientific basis and technical support for soil fissure improvement.

Description

Technical Field

[0001] This invention relates to a research method for studying the regulatory mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid, belonging to the field of soil improvement technology. Background Technology

[0002] Soil fissures are a common phenomenon formed under the influence of factors such as alternating wet and dry periods and external forces. This is especially true in soil types such as saline-alkali soils and degraded alluvial soils in the Loess Plateau irrigation area. The development of fissures leads to a decline in soil water and fertilizer retention capacity, increased deep water infiltration, and restricted crop growth. It can also cause ecological and environmental problems such as soil erosion. Traditional methods for controlling soil fissures often employ single physical or chemical amendments, which have limitations such as limited effectiveness, potential for secondary environmental pollution, and lack of low-carbon compatibility.

[0003] Micro- and nano-bubble water, with its small particle size, large specific surface area, and strong stability, can rapidly penetrate deep into soil layers, breaking up soil compaction and optimizing soil pore distribution. γ-polyglutamic acid, as a biodegradable polymer, possesses excellent water retention and binding properties, improving soil structural stability. Coupling these two technologies for soil fissure regulation holds promise for synergistic effects; however, the lack of systematic and scientific research methods makes it difficult to determine the optimal parameter combination and regulation mechanism, limiting the widespread application of this technology. Therefore, there is an urgent need to develop a research method for studying the regulation mechanism of soil fissures using micro- and nano-bubble water coupled with γ-polyglutamic acid, which balances regulatory effectiveness, environmental protection, and low carbon emissions. Summary of the Invention

[0004] In view of this, the present invention provides a research method for the regulation mechanism of soil fissures by micro-nano bubble water coupled with γ-polyglutamic acid, aiming to clarify the regulation law of soil fissures by the coupling of micro-nano bubble water and γ-polyglutamic acid, screen the optimal coupling parameter combination with low carbon adaptability, and provide scientific basis and technical support for soil fissure improvement.

[0005] This invention provides a method for studying the regulatory mechanism of micro / nano bubble water-coupled γ-polyglutamic acid on soil fissures. The proposed technical solution includes the following steps:

[0006] S1: Collect and preprocess soil samples;

[0007] S2: Mix the γ-polyglutamic acid solution with the soil sample evenly;

[0008] S3: Layer the mixed soil into containers and compact it to the preset bulk density;

[0009] S4: Use micro-nano bubble water to slowly spray and irrigate the soil until the soil moisture content reaches saturation.

[0010] S5: After the saturated soil has been left to stand for a predetermined time, it is placed in a preset temperature and humidity environment for dry-wet cycle treatment.

[0011] S6: Coupling parameter optimization. An improved ant colony algorithm is used to generate an initial solution. The carbon emission factor is introduced as heuristic information to optimize the path selection probability formula and construct a low-carbon adaptability coupling parameter combination scheme.

[0012] Furthermore, in step S1, the soil sample is saline-alkali soil or degraded alluvial soil from the Loess Plateau irrigation area, and the soil texture covers three types: sandy, loamy, and clayey; the pretreatment includes:

[0013] Remove roots, stones, weeds and other impurities from the soil;

[0014] After being sieved through a 2mm standard screen, the soil is air-dried until its moisture content stabilizes to ensure uniform soil particle size.

[0015] Furthermore, in step S2, the amount of the γ-polyglutamic acid solution applied is 0.1-0.3 t·ha. -1 .

[0016] Furthermore, in step S3, the soil is layered and filled with a thickness of 1 cm per layer to ensure that the soil bulk density is uniform and consistent, so as to avoid erosion of the soil surface during the spraying of micro-nano bubble water.

[0017] Furthermore, in step S4, the micro-nano bubble water is prepared using a micro-nano bubble generator, and the gas introduced is selected from air, oxygen, or ozone, with an introduction rate of 0.5-1.5 L·min. -1 The micro-nano bubble water has a particle size range of 100nm-50μm, and the micro-nano bubble generator is equipped with a precision flow control valve with a flow rate adjustment range of 0-2L / min.

[0018] Furthermore, in step S5, the saturated soil is left to stand for a predetermined time of 24 hours to ensure that the moisture, soil, and γ-polyglutamic acid are fully integrated.

[0019] Furthermore, in step S5, the wet-dry cycle treatment includes: placing saturated soil in an environment with a temperature of 20±5℃ and a relative humidity of 40±10% to conduct a wet-dry cycle test. During the drying stage, the soil is considered to be dry and stable when the moisture content change is less than 0.2%. During the humidification stage, water is sprayed evenly with a pneumatic sprayer until the soil cracks are completely closed. The wet-dry cycle is repeated 2-4 times.

[0020] Furthermore, in step S6, the path selection probability formula for introducing the carbon emission factor is:

[0021]

[0022] in, Let be the probability that the k-th ant moves from node i to node j at time t; Let t be the pheromone concentration from node i to node j. The function is used as a heuristic to characterize the regulation efficiency of soil fissures by the coupling of micro / nano bubble water and γ-polyglutamic acid. α is the carbon emission factor function, representing the low-carbon adaptability of the coupling parameter combination; α is the pheromone importance factor, β is the regulation efficiency heuristic factor, γ is the carbon emission factor weight coefficient, and α>0, β>0, γ>0; allowedk is the set of nodes to be visited by the k-th ant.

[0023] Furthermore, the carbon emission factor function The expression is:

[0024]

[0025] in, Let be the carbon emissions from node i to node j at time t. The maximum carbon emissions for all combinations of coupling parameters; The minimum carbon emissions for all combinations of coupling parameters, and ∈(0,1).

[0026] The beneficial effects of this invention are:

[0027] Significant synergistic regulation effect: Due to its small size, micro-nano bubble water can preferentially penetrate into the deep soil layer, break up the soil compaction structure, optimize the soil pore distribution, and provide a physical channel for the uniform diffusion of γ-polyglutamic acid; γ-polyglutamic acid forms a stable "water-colloid" structure in the optimized soil pores, and its excellent water retention properties can prolong the stabilization time of micro-nano bubbles. The two work together to achieve the dual goals of "unblocking pores" and "water retention and pore stabilization", effectively inhibiting the development of soil cracks. The regulation effect is better than that of single improvement methods.

[0028] Eco-friendly and pollution-free: The γ-polyglutamic acid used has good biodegradability. The micro-nano bubble water is prepared only from gas and water, without any chemical additives. Neither of them will leave harmful substances in the soil, will not damage the soil microbial community structure, and will not cause secondary environmental pollution, which meets the development needs of ecological agriculture.

[0029] Strong low-carbon adaptability: By introducing carbon emission factors into the ant colony algorithm, a low-carbon adaptability coupling parameter combination scheme is constructed. Under the premise of ensuring the soil fissure regulation effect, the carbon emissions in the experimental process and actual application are minimized, which responds to the concept of low-carbon development and has good sustainability. Attached Figure Description

[0030] Figure 1 This is a framework diagram of the research method for the regulation mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid according to the present invention. Detailed Implementation

[0031] The preferred embodiments of the present invention will now be described in detail.

[0032] This invention provides a method for studying the regulatory mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid. The proposed technical solution includes the following steps:

[0033] S1: Soil sample collection and pretreatment:

[0034] After collecting soil samples, immediately remove visible roots, stones, weeds, plastic and other impurities. Spread the soil evenly on a clean plastic sheet, with a thickness not exceeding 5cm, and place it in a well-ventilated and shady place to air dry naturally. Turn it over twice a day during this period to prevent localized mold growth.

[0035] After air drying, the soil was sieved through a 2mm standard sieve. Impurities on the sieve were removed again. The soil under the sieve was collected and reduced to 5kg using the quartering method. It was then packed into sealed bags for later use. The sealed bags were labeled with the soil type, texture, collection location and collection date.

[0036] The initial moisture content of the pretreated soil was determined by the drying method: 10g of soil sample was weighed, placed in an aluminum box of known mass, dried in an oven at 105℃ for 24h, cooled to room temperature and weighed, and the initial moisture content was calculated to ensure that the difference in initial moisture content among the treatment groups was ≤0.5%.

[0037] S2: γ-polyglutamic acid solution mixed with soil:

[0038] Take the pretreated soil out of the sealed bag, weigh 1021g for each group (corresponding to the container filling amount), and put it into a clean plastic basin;

[0039] According to the preset application rate gradient, the prepared γ-polyglutamic acid solution was evenly sprayed onto the soil surface. While spraying, the solution was stirred with an electric mixer for no less than 15 minutes to ensure that the solution and soil particles were fully mixed and there was no local clumping.

[0040] The mixed soil was placed in a cool place and left to stand for 12 hours to allow the moisture to be evenly distributed in preparation for subsequent filling; a blank control group was set up (no γ-polyglutamic acid solution was added, only an equal amount of deionized water was sprayed).

[0041] S3: Soil layering and compaction:

[0042] First, lay a 1cm thick layer of quartz sand and a layer of filter cloth at the bottom of the test container. Then, place the container on an electronic balance, zero it, and begin filling it with soil.

[0043] A layered filling method was adopted, with each layer containing 102.1g of soil (corresponding to a thickness of 1cm and a bulk density of 1.3g / cm³). 3 After filling, use a special compactor (9.8cm in diameter, 500g in weight) to compact vertically, repeating the compaction three times to ensure uniform soil density in each layer, with a density error ≤ ±0.05g / cm³. 3 ;

[0044] Complete the filling of 10 layers of soil in sequence. After filling, use a ruler to measure the total thickness of the soil to ensure that the total thickness is 10cm ± 0.2cm. Mark the treatment group information (soil type, texture, amount of γ-polyglutamic acid applied, type of aeration, etc.) on the outer wall of the container.

[0045] S4: Micro-nano bubble water spray irrigation:

[0046] Start the micro / nano bubble generator, select the type of gas to be introduced (air, oxygen, or ozone) according to the experimental design, and set the gas flow rate to 0.5 L / min. -1 1.0L·min -1 1.5L·min -1 Three gradients were used to adjust the bubble size to the target range (100nm-50μm) through the particle size monitoring module. After 30 minutes of stable operation, spraying began.

[0047] The test container was placed on a tray and sprayed slowly from the top. The micro-nano bubble water spray flow rate was set to 1L / min. The spraying time was controlled by a timer until the soil moisture content reached saturation (the soil moisture content no longer increased and water began to seep from the bottom permeable holes).

[0048] During the spraying process, the soil moisture content was monitored in real time using a soil moisture meter, and the data was recorded every 5 minutes to ensure that the difference in saturated moisture content between the treatment groups was ≤1%. After saturation, the spraying was stopped, and the container was left to stand for 30 minutes to drain excess free water.

[0049] S5: Saturated soil settling and wet-dry cycle treatment:

[0050] After the soil container is saturated, it is transferred to a constant temperature and humidity incubator and left to stand at room temperature for 24 hours. During this period, direct sunlight and airflow disturbance should be avoided to ensure that the water, soil particles and γ-polyglutamic acid are fully integrated.

[0051] After settling, place the container in a constant temperature and humidity incubator, set the incubator temperature to 20±5℃ and the relative humidity to 40±10%, and begin the wet-dry cycle treatment:

[0052] Drying stage: Turn off the humidification function of the incubator, keep the ventilation, and measure the soil moisture content every 2 hours using a soil moisture meter. When the change value of the moisture content in 4 consecutive measurements is less than 0.2%, it is considered that the drying is stable, and the drying time is recorded.

[0053] Humidification stage: Take out the container and use a pneumatic sprayer to spray water evenly onto the soil surface (spraying flow rate is 0.5L / min). While spraying water, observe the changes in soil cracks and take real-time pictures through the crack image acquisition system. When the image analysis software shows that the crack closure rate is ≥98%, stop spraying water and record the humidification amount.

[0054] Repeat the above drying-humidification process, performing 2, 3, and 4 dry-wet cycles respectively. After each cycle, use a crack image acquisition system to capture images of cracks on the soil surface and profile, and measure indicators such as crack density, crack width, and crack area ratio.

[0055] S6: Coupling Parameter Optimization and Data Monitoring

[0056] Parameter combination design: Using γ-polyglutamic acid application amounts (A: 0.1, 0.2, 0.3 t·ha) -1 Micro-nano bubble water aeration types (B: air, oxygen, ozone), aeration rates (C: 0.5, 1.0, 1.5 L·min) -1 The number of wet-dry cycles (D: 2, 3, 4 times) were considered as influencing factors. An orthogonal experimental design was adopted, and a total of 3×3×3×3=81 sets of coupling parameter combinations were set.

[0057] Initial solution generation: An improved ant colony algorithm is adopted, with 81 sets of parameter combinations as nodes to be visited. The initial number of ants is 50, the initial value of pheromone concentration is τ0=0.1, the pheromone importance factor is α=1.5, the regulation efficiency heuristic factor is β=2.0, the carbon emission factor weight coefficient is γ=1.0, and the number of iterations is set to 100.

[0058] Heuristic function calculation for control efficiency: The crack control efficiency η for each parameter combination is obtained using crack image analysis software. ij (t), calculated as follows: η ij (t) = (Percentage of fracture area in the blank control group - Percentage of fracture area in this group) / Percentage of fracture area in the blank control group × 100%, η ij The larger the value of (t), the higher the regulation efficiency;

[0059] Carbon emission factor calculation: The carbon emissions (CO) of each parameter combination during the entire experimental process (solution preparation, bubble preparation, wet-dry cycle) were measured using a carbon emission monitor. ij (t), calculate the maximum carbon emissions CO for all combinations. maxand minimum carbon emissions CO min Substituting into the formula, the carbon emission factor S is calculated. ij (t):

[0060]

[0061] Path selection and parameter optimization: Each ant selects a path based on the probability formula:

[0062]

[0063] After moving from the current node to the next node and completing one iteration, update the pheromone concentration (τ). ij (t+1)=(1-ρ)τ ij (t)+∑ k =1 n Δτ ij ᵏ, where ρ is the pheromone evaporation coefficient, with a value of 0.1; Δτ ij ᵏ represents the pheromone increment left by the k-th ant at node ij).

[0064] After the iteration is completed, select the regulation efficiency η. ij (t)≥80% and carbon emission factor S ij (t)≥0.

[0065] In summary, the present invention has the following advantages:

[0066] Significant synergistic regulation effect: Due to its small size, micro-nano bubble water can preferentially penetrate into the deep soil layer, break up the soil compaction structure, optimize the soil pore distribution, and provide a physical channel for the uniform diffusion of γ-polyglutamic acid. γ-polyglutamic acid forms a stable "water-colloid" structure in the optimized soil pores. Its excellent water retention properties can prolong the stabilization time of micro-nano bubbles. The two work together to achieve the dual goals of "unblocking pores" and "water retention and pore stabilization", effectively inhibiting the development of soil cracks. The regulation effect is better than that of single improvement methods.

[0067] Eco-friendly and pollution-free: The γ-polyglutamic acid used has good biodegradability. The micro-nano bubble water is prepared only from gas and water, without any chemical additives. Neither of them will leave harmful substances in the soil, will not damage the soil microbial community structure, and will not cause secondary environmental pollution, which meets the development needs of ecological agriculture.

[0068] Strong low-carbon adaptability: By introducing carbon emission factors into the ant colony algorithm, a low-carbon adaptability coupling parameter combination scheme is constructed. Under the premise of ensuring the soil fissure regulation effect, the carbon emissions in the experimental process and actual application are minimized, which responds to the concept of low-carbon development and has good sustainability.

[0069] The research methodology is scientific and systematic: This invention forms a complete research process from soil sample pretreatment, coupling system construction, environmental simulation to parameter optimization. The experimental conditions are precisely controlled and the parameters are set reasonably, which can comprehensively and deeply reveal the regulatory mechanism of micro-nano bubble water coupled with γ-polyglutamic acid on soil fissures, and provide a reliable scientific basis for the practical application of this technology.

[0070] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A method for studying the regulatory mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid, characterized in that... Includes the following steps: S1: Collect and preprocess soil samples; S2: Mix the γ-polyglutamic acid solution with the soil sample evenly; S3: Layer the mixed soil into containers and compact it to the preset bulk density; S4: Use micro-nano bubble water to slowly spray and irrigate the soil until the soil moisture content reaches saturation. S5: After the saturated soil has been left to stand for a predetermined time, it is placed in a preset temperature and humidity environment for dry-wet cycle treatment. S6: Coupling parameter optimization. An improved ant colony algorithm is used to generate an initial solution. The carbon emission factor is introduced as heuristic information to optimize the path selection probability formula and construct a low-carbon adaptability coupling parameter combination scheme.

2. The method for studying the regulatory mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid according to claim 1, characterized in that: In step S1, the soil sample is saline-alkali soil or degraded alluvial soil from the Loess Plateau irrigation area, and the soil texture covers three types: sandy, loamy, and clayey; the pretreatment includes: Remove roots, stones, weeds and other impurities from the soil; After being sieved through a 2mm standard screen, the soil is air-dried until its moisture content stabilizes to ensure uniform soil particle size.

3. The method for studying the regulatory mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid according to claim 1, characterized in that: In step S2, the amount of the γ-polyglutamic acid solution applied is 0.1-0.3 t·ha. -1 .

4. The method for studying the regulatory mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid according to claim 1, characterized in that: In step S3, the soil is layered and filled with a thickness of 1 cm per layer to ensure that the soil bulk density is uniform.

5. The method for studying the regulatory mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid according to claim 1, characterized in that: In step S4, the micro-nano bubble water is prepared using a micro-nano bubble generator, and the gas introduced is selected from air, oxygen, or ozone, with an introduction rate of 0.5-1.5 L·min. -1 The micro-nano bubble water has a particle size range of 100nm-50μm, and the micro-nano bubble generator is equipped with a precision flow control valve with a flow rate adjustment range of 0-2L / min.

6. The method for studying the regulatory mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid according to claim 1, characterized in that: In step S5, the saturated soil is left to stand for a predetermined time of 24 hours to ensure that the moisture, soil, and γ-polyglutamic acid are fully integrated.

7. The method for studying the regulatory mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid according to claim 1, characterized in that: In step S5, the wet-dry cycle treatment includes: placing saturated soil in an environment with a temperature of 20°C and a relative humidity of 40% to conduct a wet-dry cycle test. During the drying stage, the soil is considered to be dry and stable when the moisture content change is less than 0.2%. During the humidification stage, water is sprayed evenly with a pneumatic sprayer until the soil cracks are completely closed. The wet-dry cycle is repeated 2-4 times.

8. The method for studying the regulatory mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid according to claim 1, characterized in that: In step S6, the path selection probability formula for introducing the carbon emission factor is: in, Let be the probability that the k-th ant moves from node i to node j at time t; Let t be the pheromone concentration from node i to node j. The function is used as a heuristic to characterize the efficiency of the coupling between micro / nano bubble water and γ-polyglutamic acid in regulating soil fissures. α is the carbon emission factor function, representing the low-carbon adaptability of the coupling parameter combination; α is the pheromone importance factor, β is the regulation efficiency heuristic factor, γ is the carbon emission factor weight coefficient, and α>0, β>0, γ>0; allowedk is the set of nodes to be visited by the k-th ant.

9. The method for studying the regulatory mechanism of soil fissures by micro / nano bubble water coupled with γ-polyglutamic acid according to claim 8, characterized in that: The carbon emission factor function The expression is: in, Let be the carbon emissions from node i to node j at time t. The maximum carbon emissions for all combinations of coupling parameters; The minimum carbon emissions for all combinations of coupling parameters, and ∈(0,1).

Images