Efficient nitrogen fixation method for orange garden based on cooperation of waste compost and milk vetch

Abstract

The present application relates to waste resource utilization technical field, especially to a kind of orange garden efficient nitrogen fixation method based on waste compost and horsetail cooperation, the method includes waste is pulverized and is handled, adds microbial inoculum to carry out compost fermentation treatment, obtains microbial concentrated solution and fertilizer;The microbial concentrated solution is diluted to obtain microbial inoculum;When horsetail is planted in target area at equal interval, microbial inoculum is sprayed, and the fertilizer obtained by compost fermentation treatment is added in the soil of target area;The soil sample of the target area is obtained, the nitrogen fixation performance characterization value of soil sample is detected, whether the nitrogen fixation capacity of target area is qualified is preliminarily analyzed based on the measured nitrogen fixation performance characterization value, when determining that the nitrogen fixation capacity of target area is unqualified, the reason that the nitrogen fixation capacity of target area is unqualified is determined based on ethylene production variance;Based on the reason that the nitrogen fixation capacity of target area is unqualified, corresponding parameter is adjusted.

Description

Technical Field

[0001] This invention relates to the field of waste resource utilization technology, and in particular to an efficient nitrogen fixation method for orange orchards based on the synergistic effect of waste composting and vetch. Background Technology

[0002] In the field of citrus (orange) cultivation, insufficient soil nitrogen supply is one of the key issues restricting yield and quality. Traditional agriculture relies on chemical nitrogen fertilizers to supplement nitrogen, but long-term excessive application leads to environmental problems such as soil compaction and eutrophication of water bodies, while increasing production costs and reducing fruit flavor. Therefore, the development of ecological nitrogen fixation technology based on agricultural waste recycling and biological nitrogen fixation has become a research hotspot.

[0003] Chinese Patent Application No. CN116854524A discloses a bio-organic fertilizer and its preparation method. The composting raw materials include livestock and poultry manure, rapeseed cake, hay, straw, and a compound composting microbial agent. The compound composting microbial agent is obtained by cultivating a fermentation medium with soybean meal, molasses, and corn flour as the substrate. The livestock and poultry manure, rapeseed cake, hay, and straw are collected and thoroughly mixed. Then, the compound composting microbial agent is added and mixed evenly with water. The mixture is piled into windrows and turned over every 7 days. After composting fermentation, the fertilizer is obtained. This invention uses agricultural waste as raw material and rhizosphere growth-promoting bacteria as the compound composting microbial agent. The production process is simple, the production cycle is short, and the effective viable bacteria count is greater than or equal to 3.5 × 10¹⁰ CFU / ml. It can effectively achieve efficient resource utilization, contribute to environmental protection, and eliminate the hidden dangers and harms of pathogens and insect eggs. It also has the effects of inhibiting bacteria, preventing soil compaction, dissolving phosphorus and releasing potassium, fixing nitrogen, and promoting root growth.

[0004] However, existing technologies still have the following problems: Current nitrogen fixation performance testing relies on static indicators such as total nitrogen and available nitrogen in the soil, which cannot reflect the activity of microbial nitrogenases (such as the dynamic effects of rhizobia and free-living nitrogen-fixing bacteria) in real time. When the nitrogen fixation effect is not up to standard, it is difficult to distinguish whether it is a compost quality problem or a green manure cultivation problem (such as insufficient total nitrogen fixation due to sparse planting of vetch), which leads to blind adjustment strategies and long cycles. Summary of the Invention

[0005] To address this, the present invention provides a highly efficient nitrogen fixation method for orange orchards based on the synergistic effect of waste composting and hairy vetch, which overcomes the limitations of existing technologies that rely on static indicators such as total nitrogen and available nitrogen in the soil for nitrogen fixation performance testing. These methods cannot reflect the dynamic activity of microbial nitrogenases (such as rhizobia and free-living nitrogen-fixing bacteria) in real time. Furthermore, when the nitrogen fixation effect is not up to standard, it is difficult to distinguish whether the problem is due to compost quality or green manure cultivation (such as insufficient total nitrogen fixation caused by sparse hairy vetch planting), leading to blind adjustment strategies and long cycles.

[0006] To achieve the above objectives, this invention provides a highly efficient nitrogen fixation method for orange orchards based on the synergistic effect of waste composting and vetch. It includes:

[0007] Step S1: The waste is crushed and microbial agents are added for composting and fermentation to obtain microbial concentrate and fertilizer.

[0008] Step S2: Dilute the microbial concentrate to obtain a microbial culture solution;

[0009] Step S3: When planting hairy vetch at equal intervals in the target area, spray microbial inoculum and add composted fertilizer to the soil in the target area.

[0010] Step S4: Obtain soil samples from the target area, detect the nitrogen fixation performance characterization value of the soil samples, and preliminarily analyze whether the nitrogen fixation capacity of the target area is qualified based on the measured nitrogen fixation performance characterization value. If the nitrogen fixation capacity of the target area is determined to be unqualified, the reason for the unqualified nitrogen fixation capacity of the target area is determined based on the variance of ethylene production.

[0011] Step S5: Adjust the planting interval of hairy vetch, the amount of microbial inoculum, the standard for crushed particle size, and the amount of microbial agent added based on the reasons for the unqualified nitrogen fixation capacity of the target area.

[0012] Further, in step S4, the acetylene production in each soil sample is determined using the acetylene reduction method, the average ethylene production of each soil sample is calculated, and a nitrogen fixation performance characterization value is obtained. Based on the measured nitrogen fixation performance characterization value, a preliminary analysis is conducted to determine whether the nitrogen fixation capacity of the target area is qualified, including:

[0013] If the nitrogen fixation performance characterization value is greater than or equal to the preset nitrogen fixation performance characterization value, then the nitrogen fixation capacity of the target area is deemed qualified.

[0014] If the nitrogen fixation performance characterization value is less than the preset nitrogen fixation performance characterization value, the nitrogen fixation capacity of the target area is determined to be unqualified, and the reason for the unqualified nitrogen fixation capacity is analyzed based on the variance of ethylene production in each soil sample.

[0015] Furthermore, the reasons for the failure of nitrogen fixation capacity based on the variance analysis of ethylene production in each soil sample include:

[0016] If the variance is less than or equal to the preset variance, the reason why the nitrogen fixation capacity of the target area is unqualified is that the composting process is unqualified.

[0017] If the variance is greater than the preset variance, then the reason why the nitrogen fixation capacity of the target area is unqualified is that the cultivation process of vetch is unqualified.

[0018] Furthermore, when the cultivation process of hairy vetch is deemed unqualified, the difference between the preset variance and the variance is calculated to obtain the variance difference value. Based on the variance difference value, the planting interval of hairy vetch is reduced, wherein the amount of reduction in planting interval is positively correlated with the variance difference value.

[0019] Furthermore, after adjusting the planting interval of hairy vetch, the planting interval is corrected based on the microbial content in the compost, and the amount of correction of the planting interval is negatively correlated with the microbial content in the compost.

[0020] Furthermore, after correcting the planting interval of hairy vetch, the amount of microbial inoculum is adjusted based on the distribution density of hairy vetch, and the adjustment amount of the microbial inoculum is positively correlated with the distribution density of hairy vetch.

[0021] Furthermore, after adjusting the amount of microbial inoculum, the nitrogen fixation performance characterization value is retested. If the retested nitrogen fixation performance characterization value is less than the preset nitrogen fixation performance characterization value, the composting process is deemed unqualified. The crushing particle size standard is adjusted based on the difference in the average ethylene production, and the adjustment amount of the crushing particle size standard is positively correlated with the difference in the average ethylene production.

[0022] Furthermore, after adjusting the pulverized particle size standard, the amount of microbial agent added is adjusted based on the adjusted particle size standard, and the adjustment amount of the microbial agent added is negatively correlated with the adjusted particle size standard.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention uses the acetylene reduction method to determine the ethylene production of soil samples. Its principle is based on the fact that nitrogenase, while catalyzing the nitrogen fixation reaction, also catalyzes the reduction of acetylene to ethylene. By detecting the ethylene production, the activity of nitrogenase and the nitrogen fixation intensity can be indirectly reflected. The average value of ethylene production of each soil sample is used as the "nitrogen fixation performance characterization value", which can effectively eliminate the random errors of individual samples (such as local soil disturbance, sampling deviation, etc.), and more accurately reflect the overall level of nitrogen fixation capacity of the target area, avoiding the deviation of the overall judgment of the area due to individual abnormal samples.

[0024] Furthermore, in this invention, if the variance is small (less than or equal to the preset variance), it indicates that the overall ethylene production of each sample is low and the dispersion is small, which meets the characteristics of "global factor influence". As a fertilizer that is uniformly applied to the entire area, if the quality of compost is not up to standard (such as insufficient fermentation or insufficient nutrients), it will cause the nitrogen fixation activity of all samples to decrease synchronously, and the variance will naturally be small. If the variance is large (greater than the preset variance), it indicates that the differences between samples are significant, which meets the characteristics of "local factor influence". Problems such as uneven planting density and deviation of bacterial liquid spraying in the process of hairy vetch cultivation will lead to huge differences in local nitrogen fixation capacity, and the variance will increase significantly. This diagnostic method, which deeply correlates statistical characteristics (variance) with process characteristics (global / local influence), greatly improves the accuracy of cause localization.

[0025] Furthermore, this invention uses variance difference to reflect the dispersion of sample data. A larger variance difference indicates more significant differences in vetch growth, necessitating a reduction in planting interval to increase the number of plants per unit area and enhance the spatial continuity of the nitrogen-fixing microbial community. An adjustment coefficient k ensures a strict positive correlation between the planting interval adjustment and variance difference, avoiding over-density or under-density problems caused by empirical estimation. For example, when the variance difference is... When the system calculates that the planting interval needs to be reduced by 20cm (Δd=100×0.2), the original 40cm×40cm is adjusted to 20cm×20cm, achieving precise density optimization. The formula allows for dynamic adjustment of the planting interval based on the actual variance difference, adapting to the severity of cultivation problems in different farmlands. For example: mild cultivation problems (small variance difference): the reduction Δd is small, avoiding excessive dense planting that leads to resource competition; severe cultivation problems (large variance difference): the interval is significantly shortened, quickly compensating for uneven distribution of nitrogen fixation capacity. Parameter configurability: the adjustment coefficient k can be calibrated through field experiments (e.g., each increase of 0.1 variance difference corresponds to a 10cm reduction in the interval), making the model adaptable to different varieties of hairy vetch or soil types, improving the universality of the solution.

[0026] Furthermore, when the microbial content in the compost is high, microbial resources are abundant, and increasing the spacing can reduce plant competition, allowing the roots to better utilize microbial nitrogen fixation products (such as ammonium nitrogen). When the microbial content is low, microbial resources are limited, and reducing the spacing promotes dense root distribution, enriching microorganisms through the rhizosphere effect and improving local nitrogen fixation efficiency. High-microbial-content compost combined with larger planting intervals can fully utilize the nitrogen fixation function of microorganisms and reduce the use of chemical nitrogen fertilizers. Low-microbial-content compost improves microbial utilization efficiency by reducing the spacing, avoiding additional composting costs due to insufficient microbial content.

[0027] Furthermore, the microbial inoculum (such as rhizobia and nitrogen-fixing bacteria) of this invention is the core synergistic resource for nitrogen fixation in hairy vetch. Its dosage can be precisely matched with the plant distribution density through a "positive correlation adjustment" (more dosage for higher density, less dosage for lower density). When hairy vetch is densely distributed (e.g., density increased by 30% after interval adjustment), the root system has a wide interlacing area, requiring more inoculum to meet the needs of rhizosphere microbial colonization for a large number of plants. This avoids competition for nitrogen-fixing sites due to insufficient inoculum and ensures that each hairy vetch plant can obtain sufficient symbiotic microorganisms. If the plant distribution is sparse (e.g., density decreased by 20% after correction), reducing the amount of inoculum can avoid resource waste. Excessive inoculum is prone to inactivation at low densities due to lack of host root support, or competition between microorganisms due to excessive concentration, which may reduce nitrogen fixation efficiency.

[0028] Furthermore, this invention re-detects the nitrogen fixation performance characterization value and compares it with a preset value. If the re-detected value is greater than or equal to the preset value, the adjustment is deemed effective, and the process ends. If it is still less than the preset value, a deeper composting process analysis is triggered to avoid long-term substandard nitrogen fixation capacity due to incomplete adjustments in a single instance. The substandard nitrogen fixation performance is attributed to the compost particle size, and the adjustment direction is quantified by the difference in the average ethylene production. If the particle size is too small (e.g., <1cm): the compost particles are too fine, resulting in poor air permeability. Anaerobic fermentation by microorganisms produces harmful substances (such as organic acids), inhibiting the activity of nitrogen-fixing bacteria. In this case, the particle size standard needs to be increased to improve air permeability. If the particle size is too large (e.g., >3cm): fermentation inside the particles is insufficient, and the release of effective nutrients is inadequate. In this case, the particle size standard needs to be decreased to increase the surface area for microbial action.

[0029] Furthermore, the efficiency of the microbial agent of this invention is directly related to the specific surface area of ​​the compost raw material (determined by the particle size). When the particle size is large, the raw material particles are coarse and have a small specific surface area, limiting the contact area between microorganisms and the raw material. If the agent is added at a fixed amount, the excess agent will be idle due to a lack of effective action sites, or even decrease in activity due to excessive competition among microorganisms. When the particle size is small, the raw material particles are fine and have a large specific surface area, providing sufficient action sites for microorganisms. Increasing the amount of agent added at this time can fully utilize the expanded contact area and accelerate the decomposition of the raw material. If the particle size is large but too much agent is added, the local microbial concentration will be too high, leading to rapid decomposition of the raw material and the accumulation of heat, causing local high-temperature inhibition (temperatures exceeding 65°C will kill nitrogen-fixing bacteria). Conversely, if the particle size is small but the agent is insufficient, the raw material will decompose slowly due to insufficient degradation momentum. Attached Figure Description

[0030] Figure 1 This is a flowchart of the efficient nitrogen fixation method in orange orchards based on the synergistic effect of waste composting and hairy vetch according to the present invention;

[0031] Figure 2 A flowchart for determining whether the nitrogen fixation capacity of the target area is up to standard;

[0032] Figure 3 A flowchart for determining the reasons for unqualified nitrogen fixation capacity. Detailed Implementation

[0033] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0034] It should be noted that the data in this embodiment are all derived from a comprehensive analysis and evaluation of historical data from the six months prior to this determination and the corresponding historical determination results by the system described in this invention. Those skilled in the art will understand that the system described in this invention can determine the above-mentioned parameters for a single item by selecting the value with the highest proportion based on the data distribution as the preset standard parameter, using weighted summation to obtain the value as the preset standard parameter, substituting each historical data point into a specific formula and using the value obtained by that formula as the preset standard parameter, or other selection methods, as long as the system described in this invention can clearly define different specific situations in the single-item determination process through the obtained values.

[0035] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0036] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0037] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0038] Please see Figure 1-3 As shown, Figure 1 This is a flowchart illustrating the efficient nitrogen fixation method in orange orchards based on the synergistic effect of waste composting and hairy vetch, as described in this invention. Figure 2 A flowchart for determining whether the nitrogen fixation capacity of the target area is up to standard. Figure 3 A flowchart for determining the reasons for unqualified nitrogen fixation capacity.

[0039] Step S1: The waste is crushed and microbial agents are added for composting and fermentation to obtain microbial concentrate and fertilizer.

[0040] Step S2: Dilute the microbial concentrate to obtain a microbial culture solution;

[0041] Step S3: When planting hairy vetch at equal intervals in the target area, spray microbial inoculum and add composted fertilizer to the soil in the target area.

[0042] Step S4: Obtain soil samples from the target area, detect the nitrogen fixation performance characterization value of the soil samples, and preliminarily analyze whether the nitrogen fixation capacity of the target area is qualified based on the measured nitrogen fixation performance characterization value. If the nitrogen fixation capacity of the target area is determined to be unqualified, the reason for the unqualified nitrogen fixation capacity of the target area is determined based on the variance of ethylene production.

[0043] Step S5: Adjust the planting interval of hairy vetch, the amount of microbial inoculum, the standard for crushed particle size, and the amount of microbial agent added based on the reasons for the unqualified nitrogen fixation capacity of the target area.

[0044] The waste pulverization process described in this embodiment of the invention includes using a pulverizer to pulverize the waste to a standard particle size. The optimal particle size standard can be determined experimentally. For example, different particle sizes (e.g., 0.5 cm, 1 cm, 2 cm) can be used in composting fermentation experiments to test the fermentation effect, fertilizer quality, and impact on soil nitrogen fixation capacity, thereby determining the optimal particle size standard. The microbial agent includes, but is not limited to, cellulose-decomposing bacteria, lignin-decomposing bacteria, and nitrogen-fixing bacteria. The amount of microbial agent added is equal to the total mass of the pulverized waste. The preferred mass ratio of the added cellulose-decomposing bacteria, lignin-decomposing bacteria, and nitrogen-fixing bacteria is 2:2:1. The optimal planting interval for hairy vetch can be determined by experimentally setting different planting intervals and observing the growth of hairy vetch and changes in soil nitrogen-fixing capacity. In the experiment, the plant height, root length, biomass of hairy vetch, as well as indicators such as nitrogenase activity and nitrogen-fixing bacteria in the soil can be detected to evaluate the effect of different planting intervals. For example, assuming that the soil fertility of the target area is moderate, the climate is a temperate monsoon climate with sufficient sunshine and moderate rainfall. To determine the optimal planting interval for hairy vetch, the following experiment was designed: Planting interval settings: Group A: 30 cm × 30 cm; Group B: 40 cm × 40 cm; Group C: 50 cm × 50 cm; Planting method: Hairy vetch was planted at equal intervals in the target area according to the above planting intervals; During the planting process, diluted microbial inoculum was sprayed, and composted fertilizer was added to the soil; Plant height, root length, and biomass of hairy vetch were measured regularly; After 3 months of planting, soil samples were collected from each group area to test the nitrogenase activity, nitrogen-fixing bacteria count, and soil nutrient content; Group A (30 cm × 30 cm): Hairy vetch plant height was 50 cm, root length was 20 cm, and biomass was 100 g / plant. Due to excessively high planting density, some plants shaded each other, resulting in low photosynthetic efficiency. Group B (40 cm × 40 cm): *Vigna oleifera* plants were 60 cm tall with a root length of 25 cm and a biomass of 120 g / plant. There was good ventilation and light between plants, and their growth was good. Group C (50 cm × 50 cm): *Vigna oleifera* plants were 65 cm tall with a root length of 30 cm and a biomass of 130 g / plant. Although the plants were growing well, the large planting spacing resulted in a small number of plants per unit area, limiting the improvement in soil nitrogen fixation capacity. Group A: Nitrogenase activity was... The number of nitrogen-fixing bacteria is The soil nutrient content is moderate; Group B: Nitrogenase activity is... The number of nitrogen-fixing bacteria is The soil has a high nutrient content; Group C: Nitrogenase activity is... The number of nitrogen-fixing bacteria is The soil has a high nutrient content. Regarding growth and nitrogen fixation capacity: considering both the growth of hairy vetch and the soil's nitrogen fixation capacity, group B (40 cm × 40 cm) showed the best planting interval. This interval ensures sufficient space between plants for photosynthesis and root expansion, while also ensuring a sufficient number of plants per unit area to enhance the soil's nitrogen fixation capacity. Based on the experimental results, the optimal planting interval for hairy vetch was determined to be 40 cm × 40 cm. The amount of microbial inoculant sprayed was the average of several sprays under the same hairy vetch planting conditions (including but not limited to the same planting interval, the same number of hairy vetch plants, and the same soil fertility). However, the above value is not limited to this, and those skilled in the art can adjust it according to actual conditions.

[0045] Specifically, in step S4, the acetylene production in each soil sample is determined using the acetylene reduction method, the average ethylene production of each soil sample is calculated, and a nitrogen fixation performance characterization value is obtained. Based on the measured nitrogen fixation performance characterization value, a preliminary analysis is conducted to determine whether the nitrogen fixation capacity of the target area is up to standard, including:

[0046] If the nitrogen fixation performance characterization value is greater than or equal to the preset nitrogen fixation performance characterization value, then the nitrogen fixation capacity of the target area is deemed qualified.

[0047] If the nitrogen fixation performance characterization value is less than the preset nitrogen fixation performance characterization value, the nitrogen fixation capacity of the target area is determined to be unqualified, and the reason for the unqualified nitrogen fixation capacity is analyzed based on the variance of ethylene production in each soil sample.

[0048] The preset nitrogen fixation performance characterization value in this embodiment of the invention is the minimum effective value for agro-symbiotic nitrogen fixation systems as specified in international standards. However, the above values ​​are not limited to these, and those skilled in the art can adjust them according to the actual situation.

[0049] This invention uses the acetylene reduction method to determine the ethylene production of soil samples. The principle is based on the fact that nitrogenase, while catalyzing the nitrogen fixation reaction, also catalyzes the reduction of acetylene to ethylene. By detecting the ethylene production, the activity of nitrogenase and the nitrogen fixation intensity can be indirectly reflected. The average ethylene production of each soil sample is used as the "nitrogen fixation performance characterization value", which can effectively eliminate the random errors of individual samples (such as local soil disturbance, sampling deviation, etc.), and more accurately reflect the overall level of nitrogen fixation capacity of the target area, avoiding the deviation of the overall judgment of the area due to individual abnormal samples.

[0050] Specifically, the reasons for the failure of nitrogen fixation capacity based on the variance analysis of ethylene production in each soil sample include:

[0051] If the variance is less than or equal to the preset variance, the reason why the nitrogen fixation capacity of the target area is unqualified is that the composting process is unqualified.

[0052] If the variance is greater than the preset variance, then the reason why the nitrogen fixation capacity of the target area is unqualified is that the cultivation process of vetch is unqualified.

[0053] The preset variance mentioned in this embodiment of the invention can be determined by the following method: Under laboratory conditions, using homogenized raw materials (such as pure sawdust + chicken manure, C / N=28:1) and a standardized composting process (fixed crushing particle size of 1cm, microbial agent addition of 0.2%, and turning frequency of 3 days / time), 30 parallel compost samples were prepared. After decomposition, they were uniformly applied to 30 potted orange orchards with the same microenvironment (soil texture, pH, and initial nitrogen were consistent). Each potted plant was planted with the same density of hairy vetch (200,000 plants / hectare, simulating uniform planting). An equal amount of microbial inoculum (1:500 dilution) was sprayed, and after 45 days of cultivation, rhizosphere soil was collected, and the ethylene production was detected by the acetylene reduction method. The variance of ethylene production of the 30 samples was calculated, and the minimum variance under uniform composting conditions was obtained as the preset variance. However, the above value is not limited to this, and those skilled in the art can adjust it according to the actual situation.

[0054] Understandably, the core of the composting process is to convert waste into fertilizer through microbial fermentation. The uniformity of its quality (such as nutrient content and microbial activity) is mainly determined by the particle size of the composting raw materials, the distribution of microbial agents, and fermentation conditions (temperature, humidity, etc.). If the composting process is substandard (such as insufficient fermentation, uneven mixing of raw materials, or ineffective microbial agents), it will lead to a lower overall fertilizer quality, and this substandard quality is "global"—that is, the nitrogen fixation activity (ethylene production) of all soil samples in the target area will be generally lower due to insufficient fertilizer quality, and the differences between samples will be small (because fertilizer is usually distributed as evenly as possible when applied). Therefore, when the composting process is substandard, the overall ethylene production of each soil sample will be lower, and the data dispersion will be small (small variance). Vetch is a nitrogen-fixing plant, and its nitrogen fixation capacity depends on its own growth status (such as density and root development) and the synergistic effect of rhizosphere microorganisms (the effect of microbial spraying). If key factors in the cultivation process (planting interval, uniformity of bacterial solution spraying, etc.) are problematic, it can lead to significant differences in the growth of hairy vetch in local areas. For example, planting intervals that are too large or too small, or uneven spraying of bacterial solution, can cause hairy vetch to grow vigorously in some areas (high nitrogen fixation activity and high ethylene production), while other areas may grow sparsely (low nitrogen fixation activity and low ethylene production). Ultimately, this will result in significant differences (large dispersion) in the ethylene production of each soil sample. Therefore, when the hairy vetch cultivation process is not up to standard, the ethylene production of each soil sample will not only be generally low, but the data will also have a large degree of dispersion (large variance).

[0055] In this invention, a small variance (less than or equal to the preset variance) indicates that the overall ethylene production of each sample is low and the dispersion is small, which meets the characteristics of "global factor influence". As a fertilizer that is uniformly applied to the entire area, if the quality of compost is not up to standard (such as insufficient fermentation or insufficient nutrients), it will cause the nitrogen fixation activity of all samples to decrease synchronously, and the variance will naturally be small. A large variance (greater than the preset variance) indicates that the differences between samples are significant, which meets the characteristics of "local factor influence". Problems such as uneven planting density and deviation of bacterial liquid spraying in the process of hairy vetch cultivation will lead to huge differences in local nitrogen fixation capacity, and the variance will increase significantly. This diagnostic method, which deeply correlates statistical characteristics (variance) with process characteristics (global / local influence), greatly improves the accuracy of cause localization.

[0056] Specifically, when the cultivation process of hairy vetch is deemed unqualified, the difference between the preset variance and the variance is calculated to obtain the variance difference value. Based on the variance difference value, the planting interval of hairy vetch is reduced, wherein the amount of reduction in planting interval is positively correlated with the variance difference value.

[0057] The method for reducing the planting interval of hairy vetch based on variance difference in this embodiment of the invention includes setting a specific adjustment formula to quantify the adjustment amount of the planting interval, for example: Δd=k×Δσ2, where: Δd is the reduction amount of the planting interval (unit: cm); k is the adjustment coefficient (set according to experimental data or experience, for example...). Δσ² is the variance difference; the adjustment coefficient k is determined based on experimental data. For example, suppose experiments show that for every increase... If the variance difference needs to be reduced by 10 cm, then the adjustment factor is... ;Calculate the reduction in planting interval based on the variance difference and adjustment coefficient: Δd=k×Δσ2; Adjust the planting interval of hairy vetch based on the calculation results. For example, if the original planting interval is 40 cm×40 cm and the calculated reduction in planting interval is 10 cm, then the new planting interval is 30 cm×30 cm.

[0058] This invention uses variance difference to reflect the dispersion of sample data. A larger variance difference indicates more significant differences in vetch growth, necessitating a reduction in planting interval to increase the number of plants per unit area and enhance the spatial continuity of the nitrogen-fixing microbial community. An adjustment coefficient k ensures a strict positive correlation between the planting interval adjustment and the variance difference, avoiding over-density or under-density problems caused by empirical estimation. For example, when the variance difference is... When the system calculates that the planting interval needs to be reduced by 20cm (Δd=100×0.2), the original 40cm×40cm is adjusted to 20cm×20cm, achieving precise density optimization. The formula allows for dynamic adjustment of the planting interval based on the actual variance difference, adapting to the severity of cultivation problems in different farmlands. For example: mild cultivation problems (small variance difference): the reduction Δd is small, avoiding excessive dense planting that leads to resource competition; severe cultivation problems (large variance difference): the interval is significantly shortened, quickly compensating for uneven distribution of nitrogen fixation capacity. Parameter configurability: the adjustment coefficient k can be calibrated through field experiments (e.g., each increase of 0.1 variance difference corresponds to a 10cm reduction in the interval), making the model adaptable to different varieties of hairy vetch or soil types, improving the universality of the solution.

[0059] Specifically, when adjusting the planting interval of hairy vetch, the planting interval is corrected based on the microbial content in the compost, and the amount of correction of the planting interval is negatively correlated with the microbial content in the compost.

[0060] The correction amount of the planting interval in this embodiment of the invention can be determined by the following method. In this embodiment of the invention, the correction amount of the planting interval is determined based on the microbial content in the compost, because the microbial content in the compost directly affects the nitrogen fixation capacity and growth status of vetch. The following are the specific methods and implementation steps for determining the correction amount of the planting interval. First, it is necessary to measure the microbial content in the compost. This can be accomplished through laboratory analysis or rapid on-site testing methods. Commonly used methods include: plate counting: diluting compost samples and spreading them on a culture medium, then counting colonies to determine the microbial content; quantitative real-time PCR: using specific DNA or RNA markers to quantitatively analyze the microbial content in compost. The correction amount for planting intervals is negatively correlated with the microbial content in compost. High microbial content indicates strong nitrogen fixation and nutrient supply capacity of the soil, allowing for an appropriate increase in planting intervals to avoid competition between plants. Low microbial content indicates weak nitrogen fixation and nutrient supply capacity of the soil, requiring a reduction in planting intervals to increase mutual support between plants. A specific correction formula can be used to quantify the correction amount for planting intervals, for example: Δd′=k′×(C1) where: Δd′ is the correction amount for planting intervals (unit: cm); k′ is the correction coefficient (set based on experimental data or experience, for example...). C represents the microbial content in the compost (unit: g / kg); the microbial content C in the compost is determined through laboratory analysis or rapid on-site testing methods; based on the experimental data, a correction coefficient k′ is determined. For example, assuming that experiments show that for every 1 g / kg increase in microbial content, a 50 cm increase in planting spacing is required, then the correction coefficient k′ is... Based on the microbial inoculum content and correction coefficient, calculate the correction amount for the planting interval: Δd′=k′×(C1); Based on the calculation results, correct the planting interval of hairy vetch. For example, if the original planting interval is 30 cm × 30 cm and the calculated correction amount for the planting interval is 10 cm, then the new planting interval is 40 cm × 40 cm.

[0061] When the microbial content in the compost is high, microbial resources are abundant, and increasing the spacing can reduce plant competition, allowing the roots to better utilize microbial nitrogen fixation products (such as ammonium nitrogen). When the microbial content is low, microbial resources are limited, and reducing the spacing promotes dense root distribution, enriching microorganisms through the rhizosphere effect and improving local nitrogen fixation efficiency. High-microbial-content compost combined with larger planting intervals can fully utilize the nitrogen fixation function of microorganisms and reduce the use of chemical nitrogen fertilizers. Low-microbial-content compost improves microbial utilization efficiency by reducing the spacing, avoiding additional composting costs due to insufficient microbial content.

[0062] Specifically, when correcting the planting interval of hairy vetch, the amount of microbial inoculum is adjusted based on the distribution density of hairy vetch, and the adjustment amount of the microbial inoculum is positively correlated with the distribution density of hairy vetch.

[0063] The method for determining the adjustment amount of the microbial inoculum dosage in this embodiment of the invention is the same as the method for determining the correction amount of the planting interval and the reduction amount of the planting interval. The adjustment amount of the microbial inoculum dosage is positively correlated with the distribution density of hairy vetch. It can be understood that if the distribution density of hairy vetch is high, it means that there are more plants per unit area, and more microbial inoculum is needed to support the growth and nitrogen fixation capacity of each hairy vetch plant; if the distribution density of hairy vetch is low, it means that there are fewer plants per unit area, and the required amount of microbial inoculum can be appropriately reduced.

[0064] The microbial inoculum (such as rhizobia and nitrogen-fixing bacteria) of this invention is the core synergistic resource for nitrogen fixation in hairy vetch. Its dosage can be precisely matched with the plant distribution density through a "positive correlation adjustment" (more dosage for higher density, less dosage for lower density). When hairy vetch is densely distributed (e.g., density increased by 30% after interval adjustment), the root system has a wide interlacing area, requiring more inoculum to meet the needs of rhizosphere microbial colonization for a large number of plants. This avoids competition for nitrogen fixation sites due to insufficient inoculum and ensures that each hairy vetch plant can obtain sufficient symbiotic microorganisms. If the plant distribution is sparse (e.g., density decreased by 20% after correction), reducing the amount of inoculum can avoid resource waste. Excessive inoculum is prone to inactivation at low densities due to lack of host root support, or competition between microorganisms due to excessive concentration, which may reduce nitrogen fixation efficiency.

[0065] Specifically, after adjusting the amount of microbial inoculum, the nitrogen fixation performance characterization value is retested. If the retested nitrogen fixation performance characterization value is less than the preset nitrogen fixation performance characterization value, the composting process is deemed unqualified. The crushing particle size standard is adjusted based on the difference in the average ethylene production, and the adjustment amount of the crushing particle size standard is positively correlated with the difference in the average ethylene production.

[0066] The method for determining the adjustment amount of the crushed particle size standard in this embodiment of the invention is the same as the method for determining the correction amount of the planting interval and the reduction amount of the planting interval. It can be understood that if the retested nitrogen fixation performance characterization value is much lower than the preset value, it indicates that the crushed particle size may be too small, resulting in insufficient compost fermentation. At this time, it is necessary to increase the crushed particle size standard to improve the compost fermentation effect. If the retested nitrogen fixation performance characterization value is close to the preset value, it indicates that the crushed particle size is appropriate.

[0067] This invention re-detects nitrogen fixation performance characteristics and compares them with preset values. If the re-detected value is greater than or equal to the preset value, the adjustment is deemed effective, and the process ends. If it is still less than the preset value, a deeper analysis of the composting process is triggered to avoid long-term substandard nitrogen fixation capacity due to incomplete adjustments in a single instance. Substandard nitrogen fixation performance is attributed to the particle size of the compost particles, and the adjustment direction is quantified by the difference in the average ethylene production. If the particle size is too small (e.g., <1cm), the compost particles are too fine, resulting in poor aeration. Anaerobic fermentation by microorganisms produces harmful substances (such as organic acids), inhibiting the activity of nitrogen-fixing bacteria. In this case, the particle size standard needs to be increased to improve aeration. If the particle size is too large (e.g., >3cm), internal fermentation is insufficient, leading to inadequate release of effective nutrients. In this case, the particle size standard needs to be decreased to increase the surface area for microbial interaction.

[0068] Specifically, after adjusting the pulverized particle size standard, the amount of microbial agent added (the amount of microbial agent added before fermentation) is adjusted based on the adjusted particle size standard. The adjustment amount of the microbial agent added is negatively correlated with the adjusted particle size standard.

[0069] The method for determining the adjustment amount of the microbial agent added in this embodiment of the invention is the same as the method for determining the correction amount and the reduction amount of the planting interval. It can be understood that if the standard particle size of the crushed material increases, it means that the waste particles are larger and the contact area between microorganisms and organic matter is relatively reduced. In this case, it is necessary to appropriately reduce the amount of microbial agent added to avoid resource waste and uneven fermentation caused by excessively high microbial concentration. If the standard particle size of the crushed material decreases, it means that the waste particles are smaller and the contact area between microorganisms and organic matter increases. In this case, it is necessary to appropriately increase the amount of microbial agent added to ensure that enough microorganisms can decompose the fine particles and improve fermentation efficiency.

[0070] The effectiveness of the microbial agent of this invention is directly related to the specific surface area of ​​the compost raw material (determined by the particle size). When the particle size is large, the raw material particles are coarse with a small specific surface area, limiting the contact area between microorganisms and the raw material. If the agent is added at a fixed amount, the excess agent will remain idle due to a lack of effective action sites, or even decrease in activity due to excessive competition among microorganisms. When the particle size is small, the raw material particles are fine with a large specific surface area, providing sufficient action sites for microorganisms. Increasing the amount of agent added at this time can fully utilize the expanded contact area and accelerate the decomposition of the raw material. If the particle size is large but too much agent is added, the local microbial concentration will be too high, leading to rapid decomposition of the raw material and the accumulation of heat, causing local high-temperature inhibition (temperatures exceeding 65°C will kill nitrogen-fixing bacteria). Conversely, if the particle size is small but the agent is insufficient, the decomposition of the raw material will be slow due to insufficient degradation momentum.

[0071] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0072] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A highly efficient nitrogen fixation method for orange orchards based on the synergistic effect of waste composting and vetch, characterized in that, include: Step S1: The waste is crushed and microbial agents are added for composting and fermentation to obtain microbial concentrate and fertilizer. Step S2: Dilute the microbial concentrate to obtain a microbial culture solution; Step S3: When planting hairy vetch at equal intervals in the target area, spray microbial inoculum and add composted fertilizer to the soil in the target area. Step S4: Obtain soil samples from the target area, detect the nitrogen fixation performance characterization value of the soil samples, and preliminarily analyze whether the nitrogen fixation capacity of the target area is qualified based on the measured nitrogen fixation performance characterization value. If the nitrogen fixation capacity of the target area is determined to be unqualified, the reason for the unqualified nitrogen fixation capacity of the target area is determined based on the variance of ethylene production. Step S5: Adjust the planting interval of hairy vetch, the amount of microbial inoculum, the standard for crushed particle size, and the amount of microbial agent added based on the reasons for the unqualified nitrogen fixation capacity of the target area. In step S4, the acetylene reduction method is used to determine the acetylene production in each soil sample, and the average ethylene production of each soil sample is calculated to obtain the nitrogen fixation performance characterization value. Based on the measured nitrogen fixation performance characterization value, a preliminary analysis is conducted to determine whether the nitrogen fixation capacity of the target area is qualified, including: If the nitrogen fixation performance characterization value is greater than or equal to the preset nitrogen fixation performance characterization value, then the nitrogen fixation capacity of the target area is deemed qualified. If the nitrogen fixation performance characterization value is less than the preset nitrogen fixation performance characterization value, the nitrogen fixation capacity of the target area is determined to be unqualified, and the reasons for the unqualified nitrogen fixation capacity are analyzed based on the variance of ethylene production in each soil sample. The reasons for the unsatisfactory nitrogen fixation capacity based on the variance analysis of ethylene production in each soil sample include: If the variance is less than or equal to the preset variance, the reason why the nitrogen fixation capacity of the target area is unqualified is that the composting process is unqualified. If the variance is greater than the preset variance, then the reason why the nitrogen fixation capacity of the target area is unqualified is that the cultivation process of vetch is unqualified.

2. The efficient nitrogen fixation method for orange orchards based on the synergistic effect of waste composting and vetch as described in claim 1, characterized in that, When the cultivation process of hairy vetch is deemed unqualified, the difference between the preset variance and the variance is calculated to obtain the variance difference value. Based on the variance difference value, the planting interval of hairy vetch is reduced, wherein the amount of reduction in planting interval is positively correlated with the variance difference value.

3. The efficient nitrogen fixation method for orange orchards based on the synergistic effect of waste composting and vetch as described in claim 2, characterized in that, When adjusting the planting interval of hairy vetch, the planting interval is corrected based on the microbial content in the compost, and the amount of correction of the planting interval is negatively correlated with the microbial content in the compost.

4. The efficient nitrogen fixation method for orange orchards based on the synergistic effect of waste composting and vetch as described in claim 3, characterized in that, When correcting the planting interval of hairy vetch, the amount of microbial inoculum solution is adjusted based on the distribution density of hairy vetch, and the adjustment amount of microbial inoculum solution is positively correlated with the distribution density of hairy vetch.

5. The efficient nitrogen fixation method for orange orchards based on the synergistic effect of waste composting and vetch as described in claim 4, characterized in that, When adjusting the amount of microbial inoculum, the nitrogen fixation performance characterization value is retested. If the retested nitrogen fixation performance characterization value is less than the preset nitrogen fixation performance characterization value, the composting process is deemed unqualified. The crushing particle size standard is adjusted based on the difference in the average ethylene production, and the adjustment amount of the crushing particle size standard is positively correlated with the difference in the average ethylene production.

6. The efficient nitrogen fixation method for orange orchards based on the synergistic effect of waste composting and vetch as described in claim 5, characterized in that, After adjusting the pulverized particle size standard, the amount of microbial agent added is adjusted based on the adjusted particle size standard, and the adjustment amount of the microbial agent added is negatively correlated with the adjusted particle size standard.

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