Soil nitrate nitrogen assimilation and remineralization regulation and control method based on nitrogen dynamic adjustment
By accurately controlling soil moisture, temperature and adding organic materials and ammonium nitrogen, monitoring the rate of nitrate nitrogen assimilation and remineralization, the problems of low utilization efficiency of nitrogen fertilizers and environmental pollution have been solved, and green and sustainable development of soil health and crop yields have been achieved.
Patent Information
- Application Number
- CN202510417054.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-03
- Publication Date
- 2025-07-01
AI Technical Summary
In the prior art, nitrogen fertilizer utilization efficiency is low, nitrate nitrogen loss is severe, organic material application effect is unstable, ammonium nitrogen concentration regulation is insufficient, and the dynamics of nitrate nitrogen assimilation and remineralization time are difficult to balance, resulting in soil nitrate nitrogen accumulation and environmental pollution problems.
By regulating soil moisture, temperature and cycle, adding organic materials and ammonium nitrogen, monitoring the assimilation and remineralization rates of nitrate nitrogen, optimizing the addition of organic materials and ammonium nitrogen, ensuring that the carbon-nitrogen ratio, cellulose content and carbon mineralization rates meet a specific range, combining 15N marking tracer technology monitoring and microbial community analysis, precise nitrogen management is achieved.
It has improved the utilization rate of nitrogen fertilizer, reduced nitrate nitrogen loss and environmental pollution, improved soil health and crop yield, and promoted the green and sustainable development of agriculture.
Smart Images
Figure CN120233070A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the field of soil detection technology, and particularly relates to a method for regulating soil nitrate nitrogen assimilation and remineralization based on dynamic nitrogen adjustment. Background Art
[0002] The process of converting nitrate nitrogen in soil into microbial biomass nitrogen (assimilation) and ammonium nitrogen (remineralization) is an important link in the soil nitrogen cycle. The problems and defects existing in the current prior art are as follows:
[0003] 1. Nitrate nitrogen accumulation and environmental risks: In current farmland management technologies, due to the excessive application of nitrogen fertilizers, the lack of precise nitrogen management technologies and means for regulating the dynamic processes of nitrate nitrogen (such as assimilation and remineralization), the nitrogen fertilizer input efficiency is low and nitrogen loss is serious. Moreover, it leads to a large accumulation of soil nitrate nitrogen, triggering a series of environmental problems such as surface water eutrophication and groundwater nitrate pollution, threatening the ecological environment and human health.
[0004] 2. The unstable application effect of existing organic materials: Organic materials are considered an important means to improve soil fertility and enhance nitrogen use efficiency, but their specific effects vary significantly due to factors such as soil type, carbon-nitrogen ratio, and carbon mineralization rate. A scientific application plan for promoting nitrate nitrogen assimilation based on the physical and chemical properties of organic materials (such as carbon mineralization rate, cellulose and lignin content, etc.) has not been formed.
[0005] 3. Insufficient regulation of ammonium nitrogen concentration: Microorganisms preferentially utilize ammonium nitrogen rather than nitrate nitrogen. When the ammonium nitrogen concentration in the soil is too high, the nitrate nitrogen assimilation will be inhibited, which in turn leads to the accumulation of nitrate nitrogen and an increased risk of loss. Existing nitrogen fertilizer application technologies have not effectively considered the inhibitory effect of soil ammonium nitrogen concentration on soil nitrate nitrogen assimilation.
[0006] 4. Difficulty in balancing the time dynamics of nitrate nitrogen assimilation and remineralization: Nitrate nitrogen assimilation occurs in the microbial process, but its remineralization to release ammonium nitrogen is the key nitrogen source for crop absorption. Currently, there is a lack of precise time analysis and regulation means for soil nitrate nitrogen assimilation and remineralization, especially the lack of an optimization plan under the condition of applying organic materials. Summary of the Invention
[0007] To solve the above problems, the present invention proposes a method for regulating soil nitrate nitrogen assimilation and remineralization based on dynamic nitrogen adjustment in view of the problems existing in the prior art, such as low nitrogen fertilizer utilization efficiency, serious nitrate nitrogen loss, unstable application effect of organic materials, insufficient regulation of ammonium nitrogen concentration, and difficulty in balancing the time dynamics of nitrate nitrogen assimilation and remineralization.
[0008] The specific solutions are as follows:
[0009] A method for regulating soil nitrate nitrogen assimilation and remineralization based on dynamic nitrogen adjustment, characterized in that the carbon-nitrogen ratio of the organic material is 30-50, the cellulose content is 10%-50%, the lignin content is 5%-20%, and the carbon mineralization rate is 0.5-5 mg C kg-1 d-1, comprising the following steps:
[0010] S1. Soil pretreatment;
[0011] S2. Adding organic material to the pretreated soil;
[0012] S3. Continuing to add ammonium nitrogen to the soil and regulating the concentration of ammonium nitrogen in the soil;
[0013] S4. Cultivating the soil by controlling humidity, temperature and cycle;
[0014] S5. Monitoring the rates of nitrate nitrogen assimilation and remineralization in the soil;
[0015] S6. Adjusting the addition amounts of organic material and ammonium nitrogen according to the detection results of step S5.
[0016] Furthermore, the carbon-nitrogen ratio of the organic material is 34-41, the cellulose content is 15%-30%, the lignin content is 8%-15%, and the carbon mineralization rate is 1-3 mg C kg-1 d-1. Its raw materials are plant straws (such as corn straws, wheat straws), crop residues, composts, organic fertilizers, etc.
[0017] Furthermore, step S1 is specifically: Selecting experimental soil: fluvo-aquic soil or red soil (or other farmland soils); and sieving the soil through a 2 mm sieve to remove large debris, and maintaining the field water content at 60%-70%.
[0018] Furthermore, step S2 is specifically: Adding organic material at 0.5%-3% (preferably 1%-2%) of the soil weight, and uniformly mixing it into the soil. The addition ratio and type of organic material can be adjusted according to the specific soil type to meet the requirement of promoting nitrate nitrogen assimilation.
[0019] Furthermore, step S3 is specifically: Calculating the amount of ammonium nitrogen to be supplemented according to the existing nitrogen content in the soil, and uniformly applying ammonium nitrogen to the soil, and regulating the ammonium nitrogen concentration in the soil to 15-50 mg N kg -1 。
[0020] Furthermore, the concentration range of the ammonium nitrogen is 10-100 mg N kg-1 (preferably 15-50 mg N kg-1), and it is derived from nitrogen fertilizers (such as urea, ammonium sulfate, ammonium chloride, etc.).
[0021] Further, step S4 is specifically as follows: Control the humidity, temperature, and cycle of soil cultivation. Among them, the field water content of the soil is 60% - 70%, and deionized water is sprayed for adjustment when necessary; the cultivation temperature is 20 - 30 °C (preferably 25 °C); the cultivation cycle is 10 - 30 days (preferably 15 days), and the specific cycle depends on the growth requirements of the crop and the soil conditions.
[0022] Further, step S5 is specifically as follows: Use the 15N labeling and tracing technique to monitor the rates of conversion of nitrate nitrogen in the soil into microbial biomass nitrogen (assimilation) and ammonium nitrogen (mineralization); analyze the nitrate nitrogen assimilation and mineralization characteristics at different stages by measuring the 15N recovery rates in the nitrate nitrogen pool, ammonium nitrogen pool, microbial biomass nitrogen pool, and insoluble organic nitrogen pool.
[0023] Further, step S6 is specifically as follows: According to the monitoring results of nitrate nitrogen assimilation and mineralization, adjust the addition amount of organic materials and the concentration of ammonium nitrogen. Optimize the regulation plan for different soil types. For example, select plant residues with a C:N ratio of 34 - 41 in fluvo-aquic soil, and select organic materials with a high cellulose content in red soil.
[0024] Further, the detection methods involved in this method include:
[0025] 1. Detection of ammonium nitrogen and nitrate nitrogen concentrations: Use the Kjeldahl method or ion chromatography to quantitatively analyze the contents of ammonium nitrogen and nitrate nitrogen in the soil.
[0026] 2. Monitoring of 15N assimilation and mineralization: Monitor the conversion of nitrate nitrogen into microbial biomass nitrogen (assimilation) and the ammonium nitrogen released by its mineralization through the 15N tracing technique. Measure the 15N recovery rates of the microbial biomass nitrogen pool, ammonium nitrogen pool, and insoluble organic nitrogen pool.
[0027] 3. Determination of carbon mineralization rate: Determine the carbon mineralization rate of organic materials by measuring the CO2 release amount to evaluate its impact on nitrate nitrogen assimilation.
[0028] 4. Analysis of soil microbial community: Combine high-throughput sequencing technology and microbial selective inhibition technology (such as streptomycin and cycloheximide) to quantitatively analyze the contributions of bacteria and fungi to nitrate nitrogen assimilation.
[0029] The beneficial effects of the present invention are as follows:
[0030] 1. Improve nitrogen fertilizer utilization rate and crop yield: By optimizing the dynamic regulation of soil nitrogen, promote the assimilation of nitrate nitrogen by soil microorganisms, and improve the utilization rate of nitrogen. Crops can obtain more available nitrogen during the critical growth period, thereby improving crop yield and quality. By reducing the excessive application of nitrogen fertilizer, the amount of nitrogen fertilizer applied is reduced, and the fertilizer utilization rate is effectively improved.
[0031] 2. Reduce nitrate nitrogen loss and environmental pollution. By regulating the ammonium nitrogen concentration in the soil, the present invention avoids the inhibition of nitrate nitrogen assimilation caused by excessive ammonium nitrogen concentration, reduces nitrate nitrogen loss and environmental pollution. It reduces the risk of nitrate nitrogen entering surface water through runoff and infiltrating into groundwater, effectively alleviates the problems of surface water eutrophication and groundwater nitrate pollution, and reduces the emission of greenhouse gases (such as nitrous oxide).
[0032] 3. Improve operation efficiency and save resources. By simplifying the application process of organic materials and the regulation of ammonium nitrogen concentration, the present invention reduces the labor input and operation complexity in farmland management. At the same time, the precise application of organic materials and nitrogen fertilizers reduces fertilizer waste, saves raw materials, and reduces unnecessary agricultural inputs, improving operation efficiency.
[0033] 4. Improve soil health and sustainable development. By reasonably applying organic materials, the present invention promotes the health of soil structure and soil microbial communities, increases the organic carbon content in the soil, and improves soil fertility. At the same time, it reduces the damage of excessive chemical fertilizers to the soil, contributes to the long-term sustainable use of the soil, and promotes the transformation of agriculture towards green and sustainable development.
[0034] 5. Reduce the treatment and radical cure of environmental pollution. By precisely regulating the nitrogen dynamics in the soil, the present invention effectively reduces agricultural non-point source pollution and the excessive accumulation of nitrate nitrogen in the soil, thus avoiding the spread of environmental pollution and protecting the health of water bodies, air and soil. Description of the Drawings
[0035] Figure 1 It is a graph of the average nitrate nitrogen assimilation rate and the organic material carbon mineralization rate of soil after 12 days of cultivation with different carbon sources added. Among them, the grid symbols represent four pure carbon source organic compound treatments (glucose, sodium acetate, sodium lignosulfonate, and cellulose). Different letters indicate significant differences between carbon sources (p<0.05). The error bars represent the standard deviation of the average of three replicates (n = 3).
[0036] Figure 2 It is a graph of the ammonium nitrogen (A - C) and nitrate nitrogen (D - F) concentrations in soil treated with different carbon source types and ammonium nitrogen dosages.
[0037] Among them, 0NH4 + -N, 100NH4 + -N, and 200NH4 + -N represent treatments with 0, 100, and 200 mg N kg-1 ammonium sulfate added respectively. The error bars represent the standard deviation of the average of three replicates (n = 3).
[0038] Figure 3Nitrate nitrogen assimilation rate diagrams of fluvo-aquic soil (a) and red soil (b) after 12 days of cultivation with different carbon sources added under different inhibitor treatments. Among them, different letters represent significant differences in nitrate nitrogen assimilation rate among inhibitor treatments (p<0.05). Error bars represent the standard deviation of three replicates (n = 3).
[0039] Figure 4 Contribution ratio diagrams of bacteria and fungi to nitrate nitrogen assimilation in fluvo-aquic soil (a) and red soil (b) after 12 days of cultivation with different carbon sources added. Among them, different letters represent significant differences in the contribution ratio of bacteria and fungi to nitrate nitrogen assimilation (<0.05). Error bars represent the standard deviation of three replicates (n = 3). Detailed implementation manners
[0040] The present invention will be further clarified below in conjunction with the accompanying drawings and detailed implementation manners. It should be understood that the following detailed implementation manners are only used to illustrate the present invention and not to limit the scope of the present invention.
[0041] As shown in the figure, the present invention provides a method for regulating soil nitrate nitrogen assimilation and remineralization based on nitrogen dynamics, aiming to improve soil nitrogen use efficiency, reduce nitrogen loss and environmental pollution risks, and at the same time achieve the green and sustainable development of agricultural production. This method combines the input of organic materials with modern testing technologies and process means to clarify the microbial regulation mechanism and key factors of nitrate nitrogen assimilation and remineralization, and optimize the application plan of organic materials, thereby enhancing the nitrogen retention capacity and nitrogen use efficiency of the soil. It includes the following steps:
[0042] S1. Soil pretreatment;
[0043] S2. Add organic materials to the pretreated soil;
[0044] S3. Continuously add ammonium nitrogen to the soil and regulate the concentration of ammonium nitrogen in the soil;
[0045] S4. Cultivate the soil by controlling humidity, temperature and cycle;
[0046] S5. Monitor the rates of nitrate nitrogen assimilation and remineralization in the soil;
[0047] S6. Adjust the addition amounts of organic materials and ammonium nitrogen according to the detection results of step S5.
[0048] Example 1
[0049] In this example, the carbon-nitrogen ratio of the organic material is 30-50, the cellulose content is 10%-50%, the lignin content is 5%-20%, and the carbon mineralization rate is 0.5-5 mg C kg-1 d-1.
[0050] Step S1 specifically includes: selecting experimental soil; passing the soil through a 2-mm sieve to remove large debris, and maintaining the field water content at 60%–70%.
[0051] Step S2 specifically includes: adding organic materials at 0.5%–3% of the soil weight and uniformly mixing them into the soil. The addition ratio and type of organic materials can be adjusted according to the specific soil type to meet the requirements for promoting nitrate nitrogen assimilation.
[0052] Step S3 specifically includes: calculating the amount of ammonium nitrogen to be supplemented according to the existing nitrogen content in the soil, and uniformly applying ammonium nitrogen to the soil to regulate the ammonium nitrogen concentration in the soil to 15–50 mg N kg -1 .
[0053] The concentration range of the ammonium nitrogen is 10-100 mg N kg-1 and it is sourced from nitrogen fertilizers (such as urea, ammonium sulfate, ammonium chloride, etc.).
[0054] Step S4 specifically includes: controlling the humidity, temperature, and cycle of soil cultivation. Among them, the field water content of the soil is 60%–70%, and deionized water is sprayed for adjustment when necessary; the cultivation temperature is 20–30 °C; the cultivation cycle is 10–30 days, and the specific cycle depends on the crop growth requirements and soil conditions.
[0055] Step S5 specifically includes: using the 15N-labeled tracer technique to monitor the rates of nitrate nitrogen conversion to microbial biomass nitrogen (assimilation) and ammonium nitrogen (mineralization) in the soil; analyzing the nitrate nitrogen assimilation and mineralization characteristics at different stages by measuring the 15N recovery rates in the nitrate nitrogen pool, ammonium nitrogen pool, microbial biomass nitrogen pool, and recalcitrant organic nitrogen pool.
[0056] Step S6 specifically includes: adjusting the addition amount of organic materials and the ammonium nitrogen concentration according to the monitoring results of nitrate nitrogen assimilation and mineralization. Optimize the regulation plan for different soil types. For example, select plant residues with a C:N ratio of 34–41 in fluvo-aquic soil and organic materials with a high cellulose content in red soil.
[0057] Example 2
[0058] In this example, the carbon-nitrogen ratio of the organic material is 34-41, the cellulose content is 15%–30%, the lignin content is 8%–15%, and the carbon mineralization rate is preferably 1-3 mg C kg-1d-1.
[0059] Step S1 specifically includes: selecting experimental soil; passing the soil through a 2-mm sieve to remove large debris, and maintaining the field water content at 60%–70%.
[0060] Step S2 specifically includes: adding organic materials at 1% - 2% of the soil weight and uniformly mixing them into the soil. The addition ratio and type of organic materials can be adjusted according to the specific soil type to meet the requirement of promoting nitrate nitrogen assimilation.
[0061] Step S3 specifically includes: calculating the amount of ammonium nitrogen to be supplemented according to the existing nitrogen content in the soil, uniformly applying ammonium nitrogen to the soil, and regulating the ammonium nitrogen concentration in the soil to 15 - 50 mg N kg -1 .
[0062] The concentration range of the ammonium nitrogen is 15 - 50 mg N kg-1 and it is sourced from nitrogen fertilizers (such as urea, ammonium sulfate, ammonium chloride, etc.).
[0063] Step S4 specifically includes: controlling the humidity, temperature and cultivation period of the soil cultivation. Among them, the field water content of the soil is 60% - 70%, and deionized water is sprayed for adjustment when necessary; the cultivation temperature is 25°C; the cultivation period is 15 days, and the specific period depends on the crop growth requirements and soil conditions.
[0064] Step S5 specifically includes: using the 15N-labeled tracer technique to monitor the rates of nitrate nitrogen conversion to microbial biomass nitrogen (assimilation) and ammonium nitrogen (mineralization) in the soil; analyzing the nitrate nitrogen assimilation and mineralization characteristics at different stages by measuring the 15N recovery rates in the nitrate nitrogen pool, ammonium nitrogen pool, microbial biomass nitrogen pool and recalcitrant organic nitrogen pool.
[0065] Step S6 specifically includes: adjusting the addition amount of organic materials and the ammonium nitrogen concentration according to the monitoring results of nitrate nitrogen assimilation and mineralization. Optimize the regulation plan for different soil types. For example, select plant residues with a C:N ratio of 34 - 41 in fluvo-aquic soil and select organic materials with a high cellulose content in red soil.
[0066] Through the above embodiments, the experimental results of the present invention are as follows:
[0067] 1. The significant improvement in the nitrate nitrogen assimilation rate. After adding plant residues with a carbon-nitrogen ratio of 34 - 41, the nitrate nitrogen assimilation rate is significantly increased, reaching 1.56 - 5.79 mg N kg-1d-1, which is about 5 times higher than that of the inorganic fertilizer control treatment.
[0068] 2. The critical threshold of the ammonium nitrogen concentration. When the ammonium nitrogen concentration is 15 - 50 mg N kg-1, the nitrate nitrogen assimilation reaches the best level; when it exceeds 50 mg N kg-1, the nitrate nitrogen assimilation rate significantly decreases.
[0069] 3. The significant contribution of fungi to nitrate nitrogen assimilation. Under the condition of applying organic materials with a higher cellulose content, the contribution rate of fungi to nitrate nitrogen assimilation reaches 98% - 100%, which is significantly higher than that of bacteria.
[0070] 4. Optimized dynamic balance of nitrate nitrogen. In both fluvo-aquic soil and red soil, significant improvement in the temporal dynamics of nitrate nitrogen assimilation and remineralization was observed, with reduced nitrate nitrogen accumulation, stable ammonium nitrogen supply, and sustainable nitrogen source provided for crops.
[0071] The present invention solves the following technical problems:
[0072] 1. Reducing nitrate nitrogen accumulation and loss. By precisely regulating the ammonium nitrogen concentration in the soil and scientifically applying organic materials, the assimilation of nitrate nitrogen is enhanced, the migration of nitrate nitrogen to surface water, groundwater, and the atmosphere is reduced, and agricultural non-point source pollution and environmental risks are lowered.
[0073] 2. Improving nitrogen fertilizer utilization efficiency. By regulating the soil nitrogen dynamics, optimizing the balance of nitrate nitrogen assimilation and remineralization, reducing nitrogen loss, achieving the matching of nitrogen release and crop absorption requirements, enhancing nitrogen fertilizer utilization efficiency, and reducing the over-reliance on chemical nitrogen fertilizers.
[0074] 3. Optimizing the application effect of organic materials. For different soil types (such as fluvo-aquic soil and red soil), analyzing the key physical and chemical properties of organic materials (such as carbon-nitrogen ratio, carbon mineralization rate, cellulose content, etc.), optimizing the application plan, and enhancing the role and adaptability of organic materials in promoting nitrate nitrogen assimilation.
[0075] 4. Precisely regulating the ammonium nitrogen concentration. Clarifying the key influencing mechanism and threshold range of ammonium nitrogen concentration in the soil on nitrate nitrogen assimilation, avoiding the inhibition of nitrate nitrogen assimilation by excessive ammonium nitrogen concentration, and achieving the balanced management of ammonium nitrogen and nitrate nitrogen.
[0076] 5. Balancing the temporal dynamics of nitrate nitrogen assimilation and remineralization. Clarifying the temporal rules of nitrate nitrogen assimilation and remineralization, optimizing the temporal dynamics of the two processes, synchronizing nitrogen release and crop absorption requirements, and ensuring sufficient nitrogen supply for crops during the critical growth period.
Claims
1. A method for regulating soil nitrate nitrogen assimilation and remineralization based on dynamic adjustment of nitrogen, characterized in that: The organic material has a carbon-nitrogen ratio of 30-50, a cellulose content of 10%-50%, a lignin content of 5%-20%, and a carbon mineralization rate of 0.5-5 mg C kg-1d-1, and comprises the following steps: S1. Soil pretreatment; S2. adding organic materials to the pretreated soil; S3, continue to add ammonium nitrogen to the soil and regulate the concentration of ammonium nitrogen in the soil; S4. Cultivate soil by controlling humidity, temperature and cycle; S5. Monitor the rate of nitrate assimilation and remineralization in soil; S6. According to the detection result of step S5, the addition amount of organic material and ammonium nitrogen is adjusted.
2. The method for preparing the magnetic organic framework-ionic liquid composite material according to claim 1, characterized in that: The organic material has a carbon-nitrogen ratio of 34-41, a cellulose content of 15%-30%, a lignin content of 8%-15%, and a carbon mineralization rate of 1-3 mg C kg-1d-1.
3. The method for regulating soil nitrate nitrogen assimilation and remineralization based on dynamic adjustment of nitrogen according to claim 1, characterized in that: Step S1 specifically includes: selecting experimental soil; and sieving the soil through a 2 mm sieve to remove large debris and maintain the field moisture content at 60%-70%.
4. The method for regulating soil nitrate nitrogen assimilation and remineralization based on dynamic nitrogen adjustment according to claim 1, characterized in that: Step S2 specifically includes: adding organic materials at 0.5%-3% of the weight of the soil and uniformly mixing them into the soil, wherein the organic materials are preferably added at 0.5%-3% of the weight of the soil.
5. The method for regulating soil nitrate nitrogen assimilation and remineralization based on dynamic adjustment of nitrogen according to claim 1, characterized in that: Step S3 specifically includes: calculating the amount of ammonium nitrogen required to be supplemented according to the existing nitrogen content in the soil, and evenly applying ammonium nitrogen to the soil to adjust the ammonium nitrogen concentration in the soil to 15–50 mg N kg -1 .
6. A method for regulating soil nitrate nitrogen assimilation and remineralization based on dynamic adjustment of nitrogen according to claim 5, characterized in that: The concentration of ammonium nitrogen is in the range of 10-100 mg N kg-1, preferably 15-50 mg N kg-1.
7. The method for regulating soil nitrate nitrogen assimilation and remineralization based on dynamic adjustment of nitrogen according to claim 1, characterized in that: Step S4 specifically includes: controlling the humidity, temperature and cycle of soil cultivation, wherein the field moisture content of the soil is 60%-70%; the cultivation temperature is 20-30°C, preferably 25°C; and the cultivation cycle is 10-30 days, preferably 15 days.
8. The method for regulating soil nitrate nitrogen assimilation and remineralization based on dynamic nitrogen adjustment according to claim 1, characterized in that: Step S5 is specifically as follows: using 15N labeling and tracing technology to monitor the rate of conversion of nitrate nitrogen in the soil into microbial biomass nitrogen and ammonium nitrogen; by measuring the recovery rate of 15N in the nitrate nitrogen pool, ammonium nitrogen pool, microbial biomass nitrogen pool and insoluble organic nitrogen pool, analyzing the nitrate nitrogen assimilation and remineralization characteristics at different stages.
9. The method for regulating soil nitrate nitrogen assimilation and remineralization based on dynamic nitrogen adjustment according to claim 1, characterized in that: Step S6 specifically includes: adjusting the amount of organic material added and the ammonium nitrogen concentration according to the monitoring results of nitrate nitrogen assimilation and remineralization.