Soil structure optimization method for poplar plantations based on the combination of biochar and organic fertilizer

Abstract

The present invention relates to the field of electronic digital data processing technology, and specifically discloses a method for optimizing the soil structure of a poplar plantation based on a combination of biochar and organic fertilizer. First, the initial characteristic data of the soil of the poplar plantation are collected, and the soil structure improvement index is evaluated to determine the soil optimization method. Corresponding structural optimization measures are executed according to the optimization method, and a reminder is sent to a preset display port. Afterwards, a biochar persistence evaluation and an organic pollutant cumulative risk evaluation are performed on the optimized poplar plantation area. Finally, the soil optimization configuration is updated based on these evaluation results. This process achieves precise optimization and continuous improvement of the soil structure of the poplar plantation, ensuring that the soil quality meets the growth requirements of the poplars.

Description

Technical Field

[0001] The invention relates to the technical field of electronic digital data processing, and in particular to a method for optimizing soil structure of a poplar plantation based on the combination of biochar and organic fertilizer. Background Art

[0002] Poplars are an important plantation species in northern my country and parts of southern China. They are characterized by rapid growth, strong adaptability, high economic value (such as timber production and papermaking raw materials), and significant ecological benefits (such as windbreak and sand fixation and carbon sequestration). However, the long-term, monoculture and intensive management of poplar plantations (such as continuous cropping, short rotations, and high-intensity harvesting) has led to increasingly serious soil degradation, which directly affects the productivity and sustainability of poplar plantations.

[0003] For example, patent publication CN113190785B discloses a method for determining soil topsoil quality using soil compaction and its optimization. The method includes steps 1: acquiring soil compaction data; 2: processing the data to determine soil topsoil depth; 3: determining soil topsoil quality; and 4: optimizing soil topsoil quality. Soil compaction is used to perform a staged linear regression to create a topsoil compaction curve. The inflection point of the soil compaction is then identified. Soil texture is determined based on the curve's characteristics, and topsoil quality is determined based on thickness and texture. Based on the results of the soil topsoil quality determination, topsoil quality can be optimized.

[0004] For example, the invention patent with publication number CN116258060A discloses a soil testing and formula fertilization method based on machine learning, including: collecting soil physical and chemical characteristics, fertilizer application data and yield data of various crops in each plot from multiple plots; with crop yield as the target, constructing an extreme random tree model based on soil physical and chemical characteristics and fertilizer application amount, and optimizing the parameters of the extreme random tree model; inputting the measured soil physical and chemical characteristics of different plots into the optimized extreme random tree model, with the goal of maximizing crop yield, using the cuckoo search algorithm to iteratively calculate the optimized extreme random tree model to obtain the optimal fertilizer application parameters, and based on the obtained fertilizer application parameters, obtaining a pre-sowing base fertilizer application plan that simultaneously meets the soil nutrient structure specificity and yield maximization of different plots.

[0005] Combining the above technical solutions, it was found that most existing soil structure optimization solutions focus on the short-term effects of soil optimization and are unable to predict the evolution of soil structure under long-term application, resulting in a lack of sustainability of the optimization solutions. At the same time, due to the diversity and complexity of crops and soils, most existing soil structure optimization solutions rely on fixed optimization methods, which are prone to major limitations and reduce the flexibility and adaptability of soil optimization solutions. Summary of the Invention

[0006] In response to the deficiencies of the prior art, the present invention provides a method for optimizing soil structure in poplar plantations based on a combination of biochar and organic fertilizer, which can effectively solve the problems involved in the above-mentioned background technology.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: a poplar plantation soil structure optimization method based on the combination of biochar and organic fertilizer, including: collecting initial soil characteristic data of the poplar plantation area, evaluating the soil structure improvement potential index of the poplar plantation area, and determining the optimization method of the soil in the poplar plantation area; according to the optimization method of the soil in the poplar plantation area, the optimization method is transmitted to a preset display port for soil optimization reminder, and the soil structure optimization is performed on the poplar plantation area; for the poplar plantation area where the soil structure optimization is completed, a biochar persistence evaluation and an organic pollutant cumulative risk assessment are performed; and the soil structure optimization method is configured and updated according to the biochar persistence evaluation and the organic pollutant cumulative risk assessment.

[0008] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects:

[0009] (1) The present invention provides a method for optimizing the soil structure of a poplar plantation based on a combination of biochar and organic fertilizer. First, the initial characteristic data of the soil of the poplar plantation is collected, and the soil structure improvement index is evaluated to determine the soil optimization method. According to the optimization method, corresponding structural optimization measures are executed, and a reminder is sent to a preset display port. Afterwards, the biochar persistence and organic pollutant cumulative risk assessment are performed on the optimized poplar plantation area. Finally, the soil optimization configuration is updated based on these evaluation results. This process achieves accurate optimization and continuous improvement of the soil structure of the poplar plantation, ensuring that the soil quality meets the growth requirements of the poplars.

[0010] (2) The present invention collects the initial characteristic data of the soil in the poplar plantation area and evaluates the soil structure improvement potential index in the poplar plantation area, which can fully understand the initial conditions of the poplar plantation soil, including key indicators such as the fractal dimension of soil microaggregates, soil acoustic conductivity, soil shear strength value, and soil thermal inertia. These data can reflect important information such as the structure, compactness, water and fertilizer retention capacity of the soil, and provide solid data support for the subsequent formulation of accurate soil improvement plans. Based on the comparison of the soil structure improvement potential index with the predefined threshold, it can be accurately determined whether the soil needs to be improved and which improvement method is suitable. If the index is high, it indicates that the soil structure itself is good and only requires slight optimization; if the index is low, in-depth improvement is required, thereby avoiding blind improvement and improving the pertinence and effectiveness of soil improvement.

[0011] (3) The present invention collects growth status data of random sample poplars in the poplar plantation area and evaluates the organic fertilizer growth effect index of each random sample poplar, which can quantify the effect of organic fertilizer on poplar growth into a specific value. This helps to intuitively understand the actual effect of organic fertilizer in promoting poplar growth, including the impact on key growth indicators such as leaf relative water content, malondialdehyde content, net photosynthetic rate and leaf chlorophyll content, so as to more scientifically evaluate the application value of organic fertilizer. At the same time, the optimal application amount of organic fertilizer can be determined. These growth status data and growth effect index can sensitively reflect the growth status of poplars under different soil conditions and different fertilization measures. Based on this information, problems can be discovered in a timely manner to ensure the healthy growth of poplars and improve the growth quality and productivity of the entire poplar plantation.

[0012] (4) The present invention optimizes soil structure by combining biochar with organic fertilizer, which can provide a rich carbon source and energy source for soil microorganisms and promote the reproduction and metabolic activity of soil microorganisms. Active soil microorganisms can decompose organic matter, release nutrients, synthesize soil humus, improve the ecological function of the soil, form a virtuous cycle, and further enhance the fertility and health of the soil. This combined optimization method can improve the soil's buffering capacity against environmental changes and external interference, so that the soil can better maintain the stability of its structure and function when facing adverse environmental conditions such as drought and acid rain, reduce the adverse effects of environmental changes on poplar growth, and enhance the ecological stability and sustainable development capabilities of poplar plantations. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention is further described with reference to the accompanying drawings. However, the embodiments in the accompanying drawings do not constitute any limitation to the present invention. A person skilled in the art can obtain other drawings based on the following drawings without creative effort.

[0014] Figure 1 Schematic diagram of the method of the present invention.

[0015] Figure 2 This is a flow chart for determining soil optimization methods.

[0016] Figure 3 The flowchart is executed for the first soil optimization method. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0018] Reference Figure 1 As shown, the present invention provides a poplar plantation soil structure optimization method based on the combination of biochar and organic fertilizer, including: collecting initial soil characteristic data of the poplar plantation area, evaluating the soil structure improvement potential index of the poplar plantation area, and determining the optimization method of the soil in the poplar plantation area.

[0019] Determine the optimization method, such as Figure 2 As shown, Figure 2 This is a flow chart for determining soil optimization methods. Initial soil characteristic data for the poplar plantation area is collected, and the soil structure improvement potential index is evaluated. Based on the comparison of this index with a predefined threshold, the soil optimization method is determined and the corresponding action is executed. If the soil structure improvement potential index is greater than or equal to the threshold, the first soil optimization method is executed; otherwise, the second soil optimization method is executed.

[0020] According to the optimization method of the soil in the poplar plantation area, the optimization method is transmitted to the preset display port for soil optimization reminder, and structural optimization is performed on the soil in the poplar plantation area.

[0021] For poplar plantation areas where soil structure optimization has been completed, biochar persistence assessment and cumulative risk assessment of organic pollutants are conducted.

[0022] Based on the biochar persistence evaluation and the cumulative risk assessment of organic pollutants, the soil structure optimization method is configured and updated.

[0023] Specifically, the soil structure improvement index of the poplar plantation area is evaluated. The specific evaluation process is as follows:

[0024] The initial soil characteristic data of the poplar plantation area include the fractal dimension of soil microaggregates, the soil acoustic wave conductivity, the soil shear strength value and the soil thermal inertia of the poplar plantation area; the fractal dimension of soil microaggregates can be measured by a laser particle size analyzer to determine the particle size distribution; the soil acoustic wave conductivity can be measured by an acoustic soil compaction meter to emit stress waves, record the arrival time and calculate the conduction rate; the soil shear strength value can be measured by a field direct shear instrument; the soil thermal inertia can be calculated by a soil heat flux sensor to monitor the heat flux changes in the soil in real time.

[0025] The reference fractal dimension of soil microaggregates and the reference soil acoustic conductivity were extracted from the soil optimization information database.

[0026] The soil shear strength value and soil thermal inertia of the poplar plantation area were normalized to obtain normalized results. The soil acoustic wave conductivity of the poplar plantation area was deviated from the reference soil acoustic wave conductivity to obtain a deviated result. The fractal dimension of the soil microaggregate in the poplar plantation area was deviated from the reference soil microaggregate fractal dimension. The deviated results and the normalized results were weighted and aggregated to obtain the soil structure improvement index of the poplar plantation area. The specific analysis process is as follows:

[0027]

[0028] Where, It is the soil structure improvement capacity index of the poplar plantation area. is the normalized value of the fractal dimension of soil microaggregates in the poplar plantation area, is the reference fractal dimension of soil microaggregates, is the soil acoustic conductivity in the poplar plantation area, is the reference conductivity of soil acoustic waves, is the normalized value of soil shear strength in the poplar plantation area, is the normalized value of soil thermal inertia in the poplar plantation area, is the weight element corresponding to the fractal dimension of soil microaggregates predefined in the soil optimization information database, The weight element corresponding to the soil acoustic conductivity predefined in the soil optimization information library, is the weight element corresponding to the soil shear strength value predefined in the soil optimization information library, It is the weight element corresponding to the soil thermal inertia predefined in the soil optimization information library.

[0029] It should be explained that the soil microaggregate fractal dimension mentioned above refers to the fractal geometric parameter of the soil microaggregate particle size distribution. A higher fractal dimension indicates a more complex soil pore network and a rougher surface. Soil acoustic conductivity refers to the speed of sound waves propagating through soil (unit: m / s), which is primarily affected by soil compaction, particle contact density, and water content. Soil shear strength refers to the maximum stress (kPa) at which soil resists shear failure. Soil thermal inertia refers to the soil's ability to withstand temperature fluctuations.

[0030] Among them, the weight element corresponding to the fractal dimension of soil microaggregate, the weight element corresponding to soil acoustic wave conductivity, the weight element corresponding to soil shear strength value and the weight element corresponding to soil thermal inertia are all extracted from the soil optimization information library, and the mapping relationship can be a one-to-one correspondence or a many-to-one relationship. For example, the fractal dimension of soil microaggregate, the soil acoustic wave conductivity, the soil shear strength value and the soil thermal inertia are respectively mapped with the weight element corresponding to the fractal dimension of soil microaggregate, the weight element corresponding to soil acoustic wave conductivity, the weight element corresponding to soil shear strength value and the weight element corresponding to soil thermal inertia preset in the soil optimization information library to form a mapping set. The real-time soil microaggregate fractal dimension, soil acoustic wave conductivity, soil shear strength value and soil thermal inertia are brought into the mapping set to obtain the weight element corresponding to the fractal dimension of soil microaggregate, the weight element corresponding to soil acoustic wave conductivity, the weight element corresponding to soil shear strength value and the weight element corresponding to soil thermal inertia.

[0031] In this embodiment, a multivariate analysis of soil microaggregate fractal dimension, soil acoustic wave conductivity, soil shear strength, and soil thermal inertia was performed, specifically considering the correlation between these parameters. Both the soil microaggregate fractal dimension and soil acoustic wave conductivity were treated at appropriate levels. When the fractal dimension is too high and deviates from the reference value, the soil pore network becomes more complex, resulting in greater energy loss and lower conductivity when acoustic waves propagate through it. Consequently, the soil acoustic wave conductivity easily deviates from the reference value, significantly reducing the soil structure improvement potential in the poplar plantation area. A fractal dimension with a high appropriate level indicates complex soil pores and a rough surface, which increases the contact area between soil particles, enhances interparticle friction and interparticle engagement, and thus improves soil shear strength and enhances soil structure improvement potential in the poplar plantation area. Similarly, when the acoustic wave conductivity is too high and deviates from the reference value, the soil typically has smaller interparticle pores, resulting in a relatively fast heat conduction rate, making it difficult to store and retain heat. Consequently, the soil thermal inertia is relatively low, which also negatively impacts the soil structure improvement potential in the poplar plantation area.

[0032] Furthermore, the optimization method of the soil in the poplar plantation area was determined. The specific determination process is as follows:

[0033] The soil optimization method for the poplar plantation area includes a first soil optimization method and a second soil optimization method.

[0034] The soil structure improvement potential index of the poplar plantation area is checked against the predefined soil structure improvement potential index threshold. If the soil structure improvement potential index of the poplar plantation area is greater than or equal to the soil structure improvement potential index threshold, the soil optimization method of the poplar plantation area is determined to be the first soil optimization method, and the first soil optimization method is executed on the soil of the poplar plantation area. If the soil structure improvement potential index of the poplar plantation area is less than the soil structure improvement potential index threshold, the soil optimization method of the poplar plantation area is determined to be the second soil optimization method, and the second soil optimization method is executed on the soil of the poplar plantation area.

[0035] When the soil structure improvement potential index in a poplar plantation area is greater than or equal to the predefined soil structure improvement potential index threshold, it indicates that the soil itself has a certain foundation and potential for structural improvement. Large-scale soil improvement is not necessary, and soil quality can be improved by further optimizing the soil structure. When the soil structure improvement potential index in a poplar plantation area is less than the predefined soil structure improvement potential index threshold, it indicates that the soil structure is poor and requires more in-depth improvement to improve soil quality and productivity. In this case, relying solely on the application of organic fertilizer or biochar may not achieve the desired improvement effect. A combination of organic fertilizer and biochar is needed to achieve improved soil structure.

[0036] Specifically, the first soil optimization method is implemented for the soil in the poplar plantation area, and the specific implementation process is as follows:

[0037] The execution process of the first soil optimization method is as follows: Figure 3 As shown, Figure 3 This is a flowchart for executing the first soil optimization method. During this method, the amount of organic fertilizer to be applied and the soil profile to be adjusted are determined based on the percentage of deviation between the soil structure improvement index and the threshold, combined with factors such as average stand age. Subsequently, during the growth monitoring cycle, the need for biochar application is determined by evaluating the organic fertilizer growth effect index and comparing it with the predicted index. If the growth effect index does not reach the predicted value, the amount of biochar to be applied is determined based on the deviation from the growth quality estimate, and soil profile optimization is performed. This allows for dynamic adjustment and precise control of the soil improvement process.

[0038] The deviation ratio of the soil structure improvement current force index in the poplar plantation area and the soil structure improvement current force index threshold is processed to obtain the first ratio of the soil structure improvement current force index in the poplar plantation area, and the adaptation factor of the organic fertilizer application amount is mapped. The average forest age of the poplar plantation area is collected, where the average forest age can be obtained by extracting the forest age of each random sample poplar from the poplar planting record and performing mean processing, and the correction factor of the organic fertilizer application amount is mapped.

[0039] The organic fertilizer application amount adaptation factor and the organic fertilizer application amount correction factor are coupled with the default organic fertilizer application amount to obtain the organic fertilizer reference application amount, which is used to adjust the default organic fertilizer application amount to the organic fertilizer reference application amount and configure the soil in the poplar plantation area.

[0040] The above-mentioned deviation proportion processing is specifically to perform difference processing on the soil structure improvement current strength index of the poplar plantation area and the soil structure improvement current strength index threshold to obtain the first deviation of the soil structure improvement current strength index of the poplar plantation area, and perform ratio processing on it with the soil structure improvement current strength index threshold to obtain the first proportion of the soil structure improvement current strength index of the poplar plantation area.

[0041] The above mapping obtains the adaptation factor of the amount of organic fertilizer application. Specifically, a mapping set between the first proportion of the soil structure improvement current force index and the adaptation factor of the amount of organic fertilizer application is obtained from the soil optimization information database, and the existing first proportion of the soil structure improvement current force index is input into the mapping set to obtain the adaptation factor of the amount of organic fertilizer application.

[0042] The above mapping obtains the organic fertilizer application correction factor. Specifically, a mapping set between the average forest age and the organic fertilizer application correction factor is obtained from the soil optimization information library, and the average forest age of the existing poplar plantation area is input into the mapping set to obtain the organic fertilizer application correction factor.

[0043] The above-mentioned organic fertilizer application amount adaptation factor and organic fertilizer application amount correction factor are coupled with the default organic fertilizer application amount. Specifically, the organic fertilizer application amount adaptation factor and organic fertilizer application amount correction factor are multiplied with the default organic fertilizer application amount to obtain the organic fertilizer reference application amount.

[0044] According to the reference application amount of organic fertilizer, a mapping set between the reference application amount of organic fertilizer and the period correction element is obtained from the soil optimization information library, the existing reference application amount of organic fertilizer is input into the mapping set, the period correction element is obtained by mapping, and the growth monitoring preset period and the growth monitoring period correction element are coupled. Specifically, the growth monitoring preset period and the growth monitoring period correction element are multiplied to obtain the growth monitoring period.

[0045] During the growth monitoring period, growth status data of randomly sampled poplars in the poplar plantation area were collected, and the organic fertilizer growth effect index of each random sample poplar was evaluated. The organic fertilizer growth effect index of the poplar plantation area was obtained by mean processing. According to the reference application amount of organic fertilizer, the corresponding organic fertilizer growth effect prediction index was found and compared with the organic fertilizer growth effect index of the poplar plantation area to determine whether biochar should be applied.

[0046] The above search obtains the corresponding organic fertilizer growth effect prediction index, specifically obtaining a mapping set between the organic fertilizer reference application amount and the organic fertilizer growth effect prediction index from the soil optimization information library, inputting the existing organic fertilizer reference application amount into the mapping set, and thereby searching for the organic fertilizer growth effect prediction index.

[0047] By comparing the soil structure improvement potential index with the threshold, the appropriate amount of organic fertilizer application is mapped and corrected based on the average forest age. This allows for precise determination of the amount of organic fertilizer to meet the soil improvement needs of poplar plantations, avoid excessive or insufficient application of organic fertilizer, and improve the efficiency and effectiveness of soil improvement. Simultaneously, during the growth monitoring cycle, poplar growth data is collected to evaluate the organic fertilizer growth effect index and compare it with the predicted index. This allows for dynamic assessment of the effect of organic fertilizer application and, based on the comparison results, timely determination of whether biochar application is necessary. This allows for dynamic adjustment and optimization of the soil improvement process, improving the flexibility and adaptability of soil improvement.

[0048] Furthermore, whether to apply biochar is determined. The specific determination process is as follows:

[0049] If the organic fertilizer growth effect index in the poplar plantation area is greater than or equal to the organic fertilizer growth effect prediction index, it is determined that there is no need to apply biochar, the reference application amount of organic fertilizer is maintained, and the reference application amount of organic fertilizer is uploaded to the soil optimization information database to update the default application amount of organic fertilizer.

[0050] If the organic fertilizer growth effect index of the poplar plantation area is less than the organic fertilizer growth effect prediction index, it is determined that biochar needs to be applied, and the organic fertilizer growth effect index of the poplar plantation area is subtracted from the organic fertilizer growth effect prediction index to obtain the growth quality estimated deviation of the poplar plantation area, and the biochar adaptation application amount is mapped to obtain the corresponding biochar application correction factor according to the reference application amount of organic fertilizer. The biochar adaptation application amount and the biochar application correction factor are coupled. Specifically, the biochar adaptation application amount is multiplied by the biochar application correction factor to obtain the biochar reference application amount to configure the soil in the poplar plantation area.

[0051] The above mapping obtains the biochar adaptation application amount. Specifically, a mapping set between the estimated growth quality deviation of the poplar plantation area and the biochar adaptation application amount is obtained from the soil optimization information library, and the existing estimated growth quality deviation of the poplar plantation area is input into the mapping set to obtain the biochar adaptation application amount through mapping.

[0052] The above search obtains the corresponding biochar application correction factor, specifically obtaining a mapping set between the reference application amount of organic fertilizer and the biochar application correction factor from the soil optimization information library, inputting the existing reference application amount of organic fertilizer into the mapping set, and thereby finding the corresponding biochar application correction factor.

[0053] This program clarifies under what circumstances biochar needs to be applied and how to determine the amount of biochar to be applied, avoiding the blind application of biochar, improving the scientificity and rationality of biochar application, and further optimizing the soil structure improvement effect. By calculating the growth quality estimation deviation to map the biochar application adaptation amount, and combining it with the biochar application correction amount for correction, the amount of biochar applied can be accurately adjusted according to the actual needs of the soil and poplars, effectively utilizing biochar resources and avoiding waste. This forms an optimization closed loop with the above-mentioned organic fertilizer application and effect evaluation, making the soil improvement process more systematic and coherent, and being able to timely adjust the next application strategy based on the evaluation results of the previous step, continuously optimizing the soil structure improvement plan, and improving the sustainability of soil improvement.

[0054] Specifically, the organic fertilizer growth effect index of each random sample of poplar trees was evaluated. The specific evaluation process is as follows:

[0055] Growth status data for each randomly sampled poplar tree in the poplar plantation area, including the deviation values ​​for leaf relative water content, net photosynthetic rate, and chlorophyll content. This growth status data can be extracted from the poplar monitoring report. Specifically, this data refers to the growth status of each randomly sampled poplar tree at the end of the growth monitoring period.

[0056] The leaf relative adaptive water content, net light adaptive rate and leaf chlorophyll adaptive content were extracted from the soil optimization information database.

[0057] In this embodiment, the deviation degree value is specifically obtained by deviating the relative water content of the leaves of each random sample poplar, the net photosynthetic rate of each random sample poplar, and the chlorophyll content of the leaves of each random sample poplar from the relative adapted water content of the leaves, the net photosynthetic rate of each random sample poplar, and the adapted chlorophyll content of the leaves, respectively, to obtain the deviation degree value of the relative water content of the leaves of each random sample poplar, the deviation degree value of the net photosynthetic rate of each random sample poplar, and the deviation degree value of the chlorophyll content of the leaves of each random sample poplar.

[0058] Extract initial growth status data for each randomly sampled poplar tree in the poplar plantation area, including the deviation values ​​for the initial leaf relative water content, the initial net photosynthetic rate, and the initial leaf chlorophyll content. Growth status data can be obtained from the poplar monitoring report. Specifically, the growth status data for each randomly sampled poplar tree at the start of the growth monitoring period is extracted.

[0059] In this embodiment, the deviation degree value is specifically obtained by deviating the initial leaf relative water content of each random sample poplar, the initial net photosynthetic rate of each random sample poplar, and the initial leaf chlorophyll content of each random sample poplar from the leaf relative adaptive water content, the net photosynthetic adaptive rate, and the leaf chlorophyll adaptive content, respectively, to obtain the deviation degree value of the initial leaf relative water content of each random sample poplar, the deviation degree value of the initial net photosynthetic rate of each random sample poplar, and the deviation degree value of the initial leaf chlorophyll content of each random sample poplar.

[0060] The deviation values ​​of the leaf relative water content of each random sample poplar from the initial leaf relative water content of each random sample poplar, the deviation values ​​of the net photosynthetic rate of each random sample poplar from the initial net photosynthetic rate of each random sample poplar, and the deviation values ​​of the leaf chlorophyll content of each random sample poplar from the initial leaf chlorophyll content of each random sample poplar were processed separately and weighted and aggregated in sequence to obtain the organic fertilizer growth effect index of each random sample poplar. The specific analysis process is as follows:

[0061]

[0062]

[0063]

[0064] Where, is the organic fertilizer growth effect index of the jth random sample poplar, j is the code of each random sample poplar, , M is the total number of random sample poplars, is the first sub-index of the organic fertilizer growth effect of the jth random sample poplar, is the second sub-index of the organic fertilizer growth effect of the j-th random sample poplar, is the deviation value of the relative water content of the leaves of the jth random sample poplar, is the deviation value of the initial leaf relative water content of the jth random sample poplar, To adapt the water content of the leaves relatively, is the deviation value of the net photosynthetic rate of the jth random sample poplar, is the deviation value of the initial net photosynthetic rate of the jth random sample poplar, For net light matching speed, is the deviation value of the chlorophyll content of the leaves of the jth random sample poplar, is the deviation value of the initial leaf chlorophyll content of the jth random sample poplar, is the adaptive content of leaf chlorophyll, is the weight element corresponding to the deviation value of leaf relative water content predefined in the soil optimization information library, is the weight element corresponding to the net photosynthetic rate deviation value predefined in the soil optimization information database, is the weight element corresponding to the deviation value of leaf chlorophyll content predefined in the soil optimization information database. is the weight element corresponding to the deviation degree value of the initial leaf relative water content predefined in the soil optimization information library, is the weight element corresponding to the initial net photosynthetic rate deviation value predefined in the soil optimization information library, is the weight element corresponding to the deviation value of the initial leaf chlorophyll content predefined in the soil optimization information library, It is the regulating factor corresponding to the growth effect index of organic fertilizer.

[0065] It should be explained that the regulating factor corresponding to the above-mentioned organic fertilizer growth effect index refers to the variable that needs to be included in the regulating factor to control environmental heterogeneity when evaluating the independent effect of organic fertilizer on poplar growth. It helps to improve the accuracy of organic fertilizer effect evaluation and reduce the environmental dependence of organic fertilizer effect. Specifically, the regulating factor corresponding to the organic fertilizer growth effect index can be obtained by: extracting the soil structure improvement current strength index of the poplar plantation area in each period of the growth monitoring cycle in real time, performing mean processing to obtain the mean of the soil structure improvement current strength index of the poplar plantation area, obtaining a mapping set between the mean of the soil structure improvement current strength index and the regulating factor from the soil optimization information database, inputting the existing mean of the soil structure improvement current strength index of the poplar plantation area into the mapping set, and mapping to obtain the regulating factor corresponding to the organic fertilizer growth effect index.

[0066] The mean value of the soil structure improvement potential index reflects the overall structural improvement potential and quality status of the soil in the poplar plantation area. The mean value of the soil structure improvement potential index can serve as an important basis for determining the adjustment factor. Under different soil structure improvement potentials, the growth effect of organic fertilizer will be affected by environmental factors to varying degrees. Therefore, it is necessary to adjust the adjustment factor according to the mean value of the soil structure improvement potential index to more accurately evaluate the independent effect of organic fertilizer.

[0067] Among them, the weight element corresponding to the leaf relative water content deviation value, the weight element corresponding to the net photosynthetic rate deviation value, the leaf chlorophyll content deviation value, the weight element corresponding to the initial leaf relative water content deviation value, the weight element corresponding to the initial net photosynthetic rate deviation value and the initial leaf chlorophyll content deviation value are all extracted from the soil optimization information library, and the mapping relationship can be a one-to-one correspondence or a many-to-one relationship. For example, the leaf relative water content deviation and the weight element corresponding to the leaf relative water content deviation value preset in the soil optimization information library form a mapping set, and the real-time leaf relative water content deviation value is brought into the mapping set to obtain the weight element corresponding to the leaf relative water content deviation value.

[0068] In this embodiment, a multivariate analysis of leaf relative water content, net photosynthetic rate, and leaf chlorophyll content was performed, specifically considering the correlation between these parameters. When the leaf relative water content is too high and deviates from the reference value, it may lead to excessive water in the cells, cell swelling, and possible impact on the stability of the cell membrane. In this case, excessive water may dilute the concentration of substances in the cells, affecting the activity of enzymes related to photosynthesis and metabolic processes, thereby reducing the net photosynthetic rate and causing it to deviate from the reference value, thereby reducing the growth effect of organic fertilizer. At the same time, excessive water may cause the aeration of leaf tissue to deteriorate, affecting oxygen diffusion, and thus affecting the normal progress of photosynthesis. In addition, excessively high leaf relative water content may inhibit chlorophyll synthesis or accelerate the degradation rate of chlorophyll, thereby reducing the chlorophyll content of the leaves. When the leaf relative water content is insufficient, the water content in the cells decreases, causing the stomata to close to reduce water loss. Stomatal closure restricts the entry of carbon dioxide, directly affecting the dark reaction of photosynthesis, and also leading to a decrease in the net photosynthetic rate.

[0069] Furthermore, the second soil optimization method is implemented for the soil in the poplar plantation area. The specific implementation process is as follows:

[0070] The deviation ratio of the soil structure improvement current capacity index in the poplar plantation area and the soil structure improvement current capacity index threshold are processed to obtain the second ratio of the soil structure improvement current capacity index in the poplar plantation area, and the adaptation ratio of the biochar-organic fertilizer combination is matched to adjust the default ratio of the biochar-organic fertilizer combination to the adaptation ratio of the biochar-organic fertilizer combination, and jointly configure the soil in the poplar plantation area.

[0071] The above matching obtains the adaptation ratio of the biochar-organic fertilizer combination, specifically, matching the second proportion of the soil structure improvement current force index of the poplar plantation area with the adaptation ratio of the biochar-organic fertilizer combination corresponding to each predefined second proportion interval of the soil structure improvement current force index, determining the specific interval of the second proportion of the soil structure improvement current force index of the poplar plantation area, and obtaining the second proportion of the soil structure improvement current force index of the poplar plantation area corresponding to the interval.

[0072] After completing the joint configuration of the soil in the poplar plantation area, during the implementation adjustment period, the soil organic matter in the poplar plantation area is extracted, and the soil organic matter in the poplar plantation area is compared with the predefined soil organic matter reference interval. When the soil organic matter in the poplar plantation area belongs to the soil organic matter reference interval, the adaptation ratio of the biochar-organic fertilizer combination is maintained, and the adaptation ratio of the biochar-organic fertilizer combination is uploaded to the soil optimization information database to update the default ratio of the biochar-organic fertilizer combination.

[0073] When the soil organic matter in the poplar plantation area did not belong to the soil organic matter reference interval, the ratio of biochar-organic fertilizer combination was adjusted.

[0074] By matching the adaptive ratio of the biochar-organic fertilizer combination to the second proportion of the soil structure improvement potential index, the combined application ratio of biochar and organic fertilizer can be precisely adjusted for soils with different improvement potentials, giving full play to the advantages of both and improving the effect and efficiency of soil improvement. During the implementation adjustment cycle, by comparing the soil organic matter with the predefined reference interval, abnormal changes in the soil organic matter content can be detected in a timely manner, and the ratio of the biochar-organic fertilizer combination can be adjusted accordingly to maintain the soil organic matter content within an appropriate range and safeguard the soil's fertility and ecological functions. This method of dynamically adjusting the combined application ratio based on soil organic matter helps to enhance the stability of soil improvement, avoid further degradation of soil structure due to large fluctuations in soil organic matter content, and ensure the long-term effect of soil improvement.

[0075] Specifically, the ratio of biochar-organic fertilizer combination is adjusted, and the specific adjustment process is as follows:

[0076] Extract the maximum value and minimum value of the soil organic matter reference interval.

[0077] If the soil organic matter in the poplar plantation area is less than the minimum value of the soil organic matter reference interval, the soil organic matter in the poplar plantation area is differenced from the minimum value of the soil organic matter reference interval to obtain the minimum deviation of the soil organic matter in the poplar plantation area, and the organic fertilizer ratio adjustment factor is mapped to increase the proportion of organic fertilizer in the biochar-organic fertilizer combination to obtain the correction ratio of the biochar-organic fertilizer combination. If the soil organic matter in the poplar plantation area is greater than the maximum value of the soil organic matter reference interval, the biochar ratio adjustment factor is matched according to the maximum deviation of the soil organic matter in the poplar plantation area to reduce the proportion of organic fertilizer in the biochar-organic fertilizer combination to obtain the correction ratio of the biochar-organic fertilizer combination, and the soil in the poplar plantation area is reconfigured based on the correction ratio of the biochar-organic fertilizer combination.

[0078] When soil organic matter is below the minimum value of the soil organic matter reference range, it indicates that the soil organic matter content is too low. Organic fertilizer is an important source of increasing soil organic matter. Increasing the proportion of organic fertilizer in the biochar-organic fertilizer combination can quickly replenish organic matter in the soil, improve soil fertility, promote the formation and stability of soil aggregates, and optimize soil structure. For example, components such as humus in organic fertilizer can bind to soil particles, increasing soil water retention and air permeability.

[0079] When soil organic matter exceeds the maximum value of the reference range, it indicates excessive soil organic matter content. Biochar itself has relatively stable chemical properties and can persist long-term after being applied to the soil. Reducing the proportion of organic fertilizer in the biochar-organic fertilizer combination, while increasing the proportion of biochar, can appropriately slow the accumulation of organic matter in the soil, preventing problems that can arise from excessive soil organic matter accumulation, such as reduced soil aeration, while also avoiding waste of biochar resources.

[0080] For example, assuming the default ratio of biochar-organic fertilizer combination is 5:5 and the adapted ratio of biochar-organic fertilizer combination is 4:6, the soil in the poplar plantation area is configured according to this ratio (40% biochar, 60% organic fertilizer), and the soil organic matter is extracted for monitoring during the implementation adjustment period.

[0081] Assume that the mapping results in an adjustment factor of +10% for the organic fertilizer ratio. Therefore, the new composition ratio is adjusted to 60% + 10% = 70% for organic fertilizer, and the corresponding biochar ratio is adjusted to 30%. Based on this revised ratio (30% biochar, 70% organic fertilizer), the soil in the poplar plantation area is reconfigured to increase soil organic matter content and optimize soil structure.

[0082] In this way, the soil organic matter content can be more accurately controlled within an appropriate range. This helps maintain good physical, chemical, and biological properties of the soil, providing a stable and high-quality soil environment for the growth of poplars. Reasonable adjustment of the ratio of biochar and organic fertilizer can give full play to the respective advantages of organic fertilizer in supplementing organic matter and biochar in improving soil structure, while avoiding unnecessary waste of resources. Different soil initial conditions and poplar growth stages may have different requirements for soil organic matter. By dynamically adjusting the ratio of the combination, soil improvement measures can be made more adaptable and flexible, thereby improving the success rate and sustainability of soil improvement.

[0083] Furthermore, the biochar sustainability evaluation process is as follows:

[0084] Real-time determination of stable carbon in biochar during the application and planting cycle 14 C content, of which 14 The C content can be monitored by accelerator mass spectrometry, based on the stability 14 The residual amount of biochar was found by looking up the content of C, and the residual amount threshold of biochar was matched according to the organic fertilizer growth effect index of the poplar plantation area.

[0085] The above-mentioned application and planting cycle specifically refers to the period of time during which the biochar-organic fertilizer combination takes effect. If the effectiveness of biochar decreases during the application and planting cycle, it is necessary to reapply the biochar. If the effectiveness of biochar decreases after the application and planting cycle, it is the normal effect of the biochar-organic fertilizer combination, and there is no need to reapply the biochar.

[0086] The actual amount of biochar applied is the amount of biochar that should be applied based on the biochar-organic fertilizer ratio. This can be obtained from the allocation records of the poplar plantation area. The residual amount of biochar is the amount remaining after application to the soil, reflecting its long-term effectiveness. It represents the amount of biochar remaining after its effect has been achieved.

[0087] The above search results in the residual amount of biochar, specifically the stability obtained from the soil optimization information library 14 The mapping set between the C content and the residual amount of biochar is used to convert the existing stability 14 The C content is input into the mapping set to find the residual amount of biochar.

[0088] The above matching obtains the biochar residue threshold, specifically, matching the organic fertilizer growth effect index of the poplar plantation area with the residue threshold corresponding to each predefined organic fertilizer growth effect index interval, determining the specific interval of the organic fertilizer growth effect index of the poplar plantation area, and obtaining the biochar residue threshold corresponding to the interval.

[0089] The organic fertilizer growth effect index reflects the effect of organic fertilizer on poplar growth, while the biochar residue threshold is related to the soil's ability to sustainably support poplar growth. Generally speaking, a high organic fertilizer growth effect index indicates a favorable soil environment and nutrient supply. At this time, less biochar is needed to maintain the soil's ability to support poplar growth, so the corresponding biochar residue threshold is relatively high. Conversely, a low organic fertilizer growth effect index suggests potential problems with soil fertility or structure, requiring more biochar to improve soil conditions to better support poplar growth, resulting in a lower biochar residue threshold. The two establish a correlation between biochar application, which is determined by matching soil fertility to poplar growth requirements.

[0090] By matching the biochar residue threshold with the organic fertilizer growth effect index, precise regulation of biochar application can be achieved. This ensures the rational use of biochar resources while meeting the growth needs of poplar trees, avoiding excessive biochar application that could lead to resource waste or potential soil ecological problems. It also helps maintain long-term soil fertility and stability, optimizes soil structure improvement, and enhances the sustainability of soil improvement measures.

[0091] The starting time point of biochar application is obtained, wherein the starting time point is specifically extracted from the configuration record of the poplar plantation area, and when the biochar residue is less than the biochar residue threshold, the persistence of the biochar is determined to have decreased, and the time point of the biochar persistence decrease is obtained. The time interval between the starting time point of biochar application and the time point of the biochar persistence decrease is recorded as the persistence maintenance duration of the biochar, and the biochar addition amount is mapped to obtain the biochar addition amount correction element. The corrected biochar addition amount is coupled with the biochar addition amount correction element, specifically, the corrected biochar addition amount is multiplied by the biochar addition amount correction element to obtain the corrected biochar addition amount. At the time point of the biochar persistence decrease, the configuration of the soil in the poplar plantation area is optimized based on the corrected biochar addition amount.

[0092] The above mapping obtains the amount of biochar added. Specifically, a mapping set between the persistence maintenance time of biochar and the amount of biochar added is obtained from the soil optimization information library, the existing persistence maintenance time of biochar is input into the mapping set, and the amount of biochar added is obtained by searching.

[0093] The above matching obtains the biochar addition amount correction element, specifically, matching the actual application amount of biochar with the addition amount correction elements corresponding to each predefined actual application amount interval, determining the specific interval of the actual application amount of biochar, and obtaining the biochar addition amount correction element corresponding to the interval.

[0094] Real-time determination of stable carbon in biochar 14 By assessing the C content, we can accurately understand the residual amount of biochar in the soil and how long it lasts, thereby determining the optimal time for biochar application, avoiding blind application, and improving the efficiency and effectiveness of soil improvement. Furthermore, based on the results of the biochar persistence assessment, we can scientifically determine the biochar addition ratio and correction ratio, rationally allocate biochar resources, and avoid resource waste. This helps ensure the long-term stability and sustainability of soil improvement, maintain good soil structure and fertility, provide protection for the continued growth of poplar trees, and prevent further degradation of soil structure due to a decrease in biochar persistence.

[0095] Specifically, the cumulative risk assessment of organic pollutants has the following specific assessment process:

[0096] During the application and planting cycle, the PAH content of the soil is collected in real time. The PAH content can be monitored by gas chromatography-mass spectrometry and compared with the predefined PAH definition content. When the PAH content of the soil is less than or equal to the PAH definition content, the cumulative risk assessment of organic pollutants is continuously performed. When the PAH content of the soil is greater than the PAH definition content, the PAH content of the soil is proportional to the PAH definition content to obtain the PAH content deviation ratio of the soil, which is compared with the predefined PAH content deviation ratio threshold:

[0097] If the polycyclic aromatic hydrocarbons (PAHs) content deviation ratio in the soil is less than or equal to the PAHs content deviation ratio threshold, the amount of iron oxide-loaded biochar applied is mapped according to the PAHs content deviation ratio in the soil, and the soil configuration in the poplar plantation area is optimized based on the amount of iron oxide-loaded biochar applied.

[0098] The above mapping obtains the application amount of iron oxide-loaded biochar. Specifically, a mapping set between the polycyclic aromatic hydrocarbon content deviation ratio of the soil and the application amount of iron oxide-loaded biochar is obtained from the soil optimization information library, and the existing polycyclic aromatic hydrocarbon content deviation ratio of the soil is input into the mapping set to obtain the application amount of iron oxide-loaded biochar.

[0099] If the PAH content deviation ratio of the soil is greater than the PAH content deviation ratio threshold, the application ratio of biochar loaded with iron oxides is mapped according to the PAH content deviation ratio of the soil, which is used to correct the proportion of biochar in the biochar-organic fertilizer combination ratio, and the application ratio of biochar loaded with iron oxides is added to maintain the biochar-organic fertilizer combination ratio. The configuration optimization of the soil in the poplar plantation area is completed based on the biochar-organic fertilizer combination ratio.

[0100] For example, assuming the original biochar-organic fertilizer combination consisted of 40% biochar and 60% organic fertilizer, and the iron oxide-loaded biochar was applied at 15%, the new biochar application ratio would be 25% + 15% = 40%. Accordingly, the organic fertilizer ratio would remain unchanged at 60%. Using this new ratio (25% biochar + 15% iron oxide-loaded biochar, 60% organic fertilizer) in the poplar plantation soil, the combination would be adjusted.

[0101] By collecting polycyclic aromatic hydrocarbon (PAH) levels in the soil, an indicator of organic pollutants, in real time and comparing them with predefined limits, we can promptly detect the accumulation of organic pollutants in the soil, take proactive measures to prevent the expansion of pollution risks, and protect the soil ecosystem. Based on the results of the cumulative risk assessment of organic pollutants, we can rationally adjust the ratio of biochar-organic fertilizer combinations or add iron oxide-loaded biochar, optimize fertilization strategies, reduce further accumulation of organic pollutants, and improve soil safety and stability. Preventing the excessive accumulation of organic pollutants in the soil can avoid adverse effects on soil microorganisms, plant growth, and the surrounding ecological environment, thereby ensuring the health and safety of the poplar plantation ecosystem.

[0102] The above content is merely an example and explanation of the structure of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the present invention, they should all fall within the scope of protection of the present invention.

Claims

1. A method for optimizing soil structure in poplar plantations based on a combination of biochar and organic fertilizer, characterized in that: include: Collect initial soil characteristic data in the poplar plantation area, evaluate the soil structure improvement index in the poplar plantation area, and determine the optimization method for the soil in the poplar plantation area; According to the optimization method of the soil in the poplar plantation area, the optimization method is transmitted to the preset display port for soil optimization reminder, and the soil structure optimization is performed on the poplar plantation area; Conduct biochar persistence assessments and organic pollutant cumulative risk assessments in poplar plantation areas where soil structure optimization has been completed. Based on the biochar persistence assessment and the cumulative risk assessment of organic pollutants, the soil structure optimization method is configured and updated; The first soil optimization method is performed on the soil in the poplar plantation area, and the specific execution process is as follows: The soil structure improvement index of the poplar plantation area and the soil structure improvement index threshold were processed for deviation ratio, and the first ratio of the soil structure improvement index of the poplar plantation area was obtained. The organic fertilizer application amount adaptation factor was mapped and the average forest age of the poplar plantation area was collected to obtain the organic fertilizer application amount correction factor. The organic fertilizer application rate adaptation factor and the organic fertilizer application rate correction factor are coupled with the default organic fertilizer application rate to obtain the organic fertilizer reference application rate, which is used to adjust the default organic fertilizer application rate to the organic fertilizer reference application rate and configure the soil in the poplar plantation area; According to the reference application amount of organic fertilizer, a period correction element is obtained by mapping, and the growth monitoring preset period is coupled with the growth monitoring period correction element to obtain the growth monitoring period; The organic fertilizer application amount adaptation factor and the organic fertilizer application amount correction factor are coupled together with the organic fertilizer default application amount, specifically, the organic fertilizer application amount adaptation factor and the organic fertilizer application amount correction factor are multiplied together with the organic fertilizer default application amount to obtain the organic fertilizer reference application amount; According to the reference application amount of organic fertilizer, a mapping set between the reference application amount of organic fertilizer and the period correction element is obtained from the soil optimization information library, the existing reference application amount of organic fertilizer is input into the mapping set, the period correction element is obtained by mapping, and the growth monitoring preset period and the growth monitoring period correction element are coupled. Specifically, the growth monitoring preset period and the growth monitoring period correction element are multiplied to obtain the growth monitoring period.

2. The method for optimizing soil structure of poplar plantations based on the combination of biochar and organic fertilizer according to claim 1, characterized in that: The specific evaluation process for evaluating the soil structure improvement index in the poplar plantation area is as follows: The initial soil characteristic data of the poplar plantation area include the fractal dimension of soil microaggregates in the poplar plantation area, the soil acoustic wave conductivity in the poplar plantation area, the soil shear strength value in the poplar plantation area, and the soil thermal inertia in the poplar plantation area; The soil microaggregate reference fractal dimension and soil acoustic wave reference conductivity were extracted from the soil optimization information database; The soil shear strength value and soil thermal inertia of the poplar plantation area were normalized respectively to obtain the normalized results. The soil acoustic wave conductivity of the poplar plantation area was deviated from the soil acoustic wave reference conductivity to obtain the deviation results. The fractal dimension of the soil microaggregate in the poplar plantation area was deviated from the soil microaggregate reference fractal dimension. The deviation results and the normalized results were weightedly aggregated in turn to obtain the soil structure improvement capacity index of the poplar plantation area.

3. The method for optimizing soil structure of poplar plantations based on the combination of biochar and organic fertilizer according to claim 1, characterized in that: The optimization method for determining the soil in the poplar plantation area is as follows: The soil optimization method of the poplar plantation area includes a first soil optimization method and a second soil optimization method; The soil structure improvement potential index of the poplar plantation area is checked against the predefined soil structure improvement potential index threshold. If the soil structure improvement potential index of the poplar plantation area is greater than or equal to the soil structure improvement potential index threshold, the soil optimization method of the poplar plantation area is determined to be the first soil optimization method, and the first soil optimization method is executed on the soil of the poplar plantation area. If the soil structure improvement potential index of the poplar plantation area is less than the soil structure improvement potential index threshold, the soil optimization method of the poplar plantation area is determined to be the second soil optimization method, and the second soil optimization method is executed on the soil of the poplar plantation area.

4. The method for optimizing soil structure of poplar plantations based on the combination of biochar and organic fertilizer according to claim 3, characterized in that: The first soil optimization method is performed on the soil in the poplar plantation area, and the specific execution process further includes: During the growth monitoring period, growth status data of randomly sampled poplars in the poplar plantation area were collected, and the organic fertilizer growth effect index of each random sample poplar was evaluated. The organic fertilizer growth effect index of the poplar plantation area was obtained by mean processing. According to the reference application amount of organic fertilizer, the corresponding organic fertilizer growth effect prediction index was found and compared with the organic fertilizer growth effect index of the poplar plantation area to determine whether biochar should be applied.

5. The method for optimizing soil structure of poplar plantations based on the combination of biochar and organic fertilizer according to claim 4, characterized in that: The specific process of determining whether to apply biochar is as follows: If the organic fertilizer growth effect index of the poplar plantation area is greater than or equal to the organic fertilizer growth effect prediction index, it is determined that biochar is not needed, the reference application amount of organic fertilizer is maintained, and the reference application amount of organic fertilizer is uploaded to the soil optimization information database to update the default application amount of organic fertilizer; If the organic fertilizer growth effect index of the poplar plantation area is less than the organic fertilizer growth effect prediction index, it is determined that biochar needs to be applied. The organic fertilizer growth effect index of the poplar plantation area is subtracted from the organic fertilizer growth effect prediction index to obtain the growth quality estimation deviation of the poplar plantation area. The biochar adaptation application amount is mapped to obtain the corresponding biochar application correction factor based on the reference application amount of organic fertilizer. The biochar adaptation application amount and the biochar application correction factor are coupled to obtain the biochar reference application amount to configure the soil in the poplar plantation area.

6. The method for optimizing soil structure of poplar plantations based on the combination of biochar and organic fertilizer according to claim 4, characterized in that: The specific evaluation process of evaluating the organic fertilizer growth effect index of each random sample of poplar is as follows: Growth status data of each randomly sampled poplar in the poplar plantation area, including a deviation value of a leaf relative water content of each randomly sampled poplar, a deviation value of a net photosynthetic rate of each randomly sampled poplar, and a deviation value of a leaf chlorophyll content of each randomly sampled poplar; Extract the initial growth status data of each random sample poplar in the poplar plantation area, including the deviation degree value of the initial leaf relative water content of each random sample poplar, the deviation degree value of the initial net photosynthetic rate of each random sample poplar, and the deviation degree value of the initial leaf chlorophyll content of each random sample poplar; The deviation values ​​of leaf relative water content of each random sample poplar and its initial leaf relative water content, the deviation values ​​of net photosynthetic rate of each random sample poplar and its initial net photosynthetic rate, and the deviation values ​​of leaf chlorophyll content of each random sample poplar and its initial leaf chlorophyll content were processed respectively, and weighted aggregation was performed in sequence to obtain the organic fertilizer growth effect index of each random sample poplar.

7. The method for optimizing soil structure of poplar plantations based on the combination of biochar and organic fertilizer according to claim 3, characterized in that: The second soil optimization method is performed on the soil in the poplar plantation area, and the specific execution process is as follows: The soil structure improvement current capacity index of the poplar plantation area and the soil structure improvement current capacity index threshold are processed for deviation proportion to obtain the second proportion of the soil structure improvement current capacity index of the poplar plantation area, and the adaptation ratio of the biochar-organic fertilizer combination is obtained by matching. The default ratio of the biochar-organic fertilizer combination is adjusted to the adaptation ratio of the biochar-organic fertilizer combination, and the soil in the poplar plantation area is jointly configured; After completing the joint configuration of the soil in the poplar plantation area, within the implementation adjustment period, extract the soil organic matter in the poplar plantation area, compare the soil organic matter in the poplar plantation area with a predefined soil organic matter reference interval, and when the soil organic matter in the poplar plantation area falls within the soil organic matter reference interval, maintain the adapted ratio of the biochar-organic fertilizer combination, and upload the adapted ratio of the biochar-organic fertilizer combination to the soil optimization information database to update the default ratio of the biochar-organic fertilizer combination; When the soil organic matter in the poplar plantation area did not belong to the soil organic matter reference interval, the ratio of biochar-organic fertilizer combination was adjusted.

8. The method for optimizing soil structure of poplar plantations based on the combination of biochar and organic fertilizer according to claim 7, characterized in that: The ratio of the biochar-organic fertilizer combination is adjusted, and the specific adjustment process is as follows: Extract the maximum value and minimum value of the soil organic matter reference interval; If the soil organic matter in the poplar plantation area is less than the minimum value of the soil organic matter reference interval, the soil organic matter in the poplar plantation area is differenced from the minimum value of the soil organic matter reference interval to obtain the minimum deviation of the soil organic matter in the poplar plantation area, and the organic fertilizer ratio adjustment factor is mapped to increase the proportion of organic fertilizer in the biochar-organic fertilizer combination to obtain the correction ratio of the biochar-organic fertilizer combination. If the soil organic matter in the poplar plantation area is greater than the maximum value of the soil organic matter reference interval, the biochar ratio adjustment factor is matched according to the maximum deviation of the soil organic matter in the poplar plantation area to reduce the proportion of organic fertilizer in the biochar-organic fertilizer combination to obtain the correction ratio of the biochar-organic fertilizer combination, and the soil in the poplar plantation area is reconfigured based on the correction ratio of the biochar-organic fertilizer combination.

9. The method for optimizing soil structure of poplar plantations based on the combination of biochar and organic fertilizer according to claim 1, characterized in that: The specific evaluation process of the biochar persistence evaluation is as follows: Real-time determination of stable carbon in biochar during the application and planting cycle 14 C content, based on stability 14 C content, find the residual amount of biochar, and match the residual threshold of biochar according to the organic fertilizer growth effect index of the poplar plantation area; The starting time point of biochar application is obtained, and when the residual amount of biochar is less than the residual amount threshold of biochar, the persistence of biochar is determined to have decreased, and the time point of biochar persistence decrease is obtained. The time interval between the starting time point of biochar application and the time point of biochar persistence decrease is recorded as the persistence maintenance duration of biochar, and the biochar addition amount is mapped to obtain the biochar addition amount correction element according to the actual application amount of biochar. The corrected biochar addition amount is coupled with the biochar addition amount correction element to obtain the corrected biochar addition amount. At the time point of biochar persistence decrease, the soil configuration of the poplar plantation area is optimized based on the corrected biochar addition amount.

10. The method for optimizing soil structure of poplar plantations based on the combination of biochar and organic fertilizer according to claim 1, characterized in that: The specific assessment process of the cumulative risk assessment of organic pollutants is as follows: During the application and planting cycle, the PAH content of the soil is collected in real time and compared with the predefined PAH limit content. When the PAH content of the soil is less than or equal to the PAH limit content, the cumulative risk assessment of organic pollutants is continuously performed. When the PAH content of the soil is greater than the PAH limit content, the PAH content of the soil and the PAH limit content are processed as a ratio to obtain the PAH content deviation ratio of the soil, which is compared with the predefined PAH content deviation ratio threshold: If the polycyclic aromatic hydrocarbon content deviation ratio of the soil is less than or equal to the polycyclic aromatic hydrocarbon content deviation ratio threshold, the application amount of iron oxide-loaded biochar is mapped according to the polycyclic aromatic hydrocarbon content deviation ratio of the soil, and the soil configuration of the poplar plantation area is optimized based on the application amount of iron oxide-loaded biochar; If the PAH content deviation ratio of the soil is greater than the PAH content deviation ratio threshold, the application ratio of biochar loaded with iron oxides is mapped according to the PAH content deviation ratio of the soil, which is used to correct the proportion of biochar in the biochar-organic fertilizer combination ratio, and the application ratio of biochar loaded with iron oxides is added to maintain the biochar-organic fertilizer combination ratio. The configuration optimization of the soil in the poplar plantation area is completed based on the biochar-organic fertilizer combination ratio.

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