Poplar man-made forest soil structure optimization method based on combination of biochar and organic fertilizer

Abstract

The invention relates to the technical field of electric digital data processing, and particularly discloses a poplar man-made forest soil structure optimization method based on combination of charcoal and organic fertilizer, which comprises the following steps: firstly, collecting soil initial characteristic data of a poplar man-made forest, and evaluating a soil structure improvement now force index to determine a soil optimization mode; and executing corresponding structure optimization measures according to the optimization mode, and sending a prompt to a preset display port. And then performing charcoal persistence evaluation and organic pollutant accumulation risk evaluation on the optimized poplar man-made forest area. And finally, updating the soil optimization configuration according to the evaluation results. The process realizes accurate optimization and continuous improvement of the soil structure of the artificial poplar forest, and ensures that the soil quality meets the growth requirements of poplar.

Description

Technical Field

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

[0002] Poplar is an important tree species for plantation forests in northern China and some southern regions. It has characteristics such as fast growth rate, strong adaptability, high economic value (such as wood production, papermaking raw materials), and significant ecological benefits (such as wind prevention and sand fixation, carbon sequestration function). However, the long-term single and intensive management mode of poplar plantations (such as continuous cropping, short rotation period, high-intensity harvesting) has led to increasingly prominent problems of soil structure degradation, which directly affects the productivity sustainability of poplar plantations.

[0003] For example, the invention patent with the publication number CN113190785B discloses a method for judging the quality of the cultivated layer of soil and optimizing it using compactness, including step one, obtaining soil compactness data; step two, processing the data to obtain the depth of the cultivated layer of soil: step three, judging the quality of the cultivated layer of soil; step four, optimizing the quality of the cultivated layer of soil. Using soil compactness for stepwise linear regression, making a compactness curve of the cultivated layer, finding the inflection point of soil compactness, judging the soil texture according to the curve characteristics, judging the quality of the cultivated layer by thickness and texture, and according to the judgment result of the quality of the cultivated layer of soil, the quality of the cultivated layer of soil can be optimized.

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

[0005] Combining the above technical solutions, it is found that most of the existing soil structure optimization schemes focus on the short-term effects of soil optimization and cannot predict the evolution of soil structure under long-term application, resulting in the lack of sustainability of the optimization scheme; at the same time, due to the diversity and complexity of crops and soil, and most of the existing soil structure optimization schemes rely on fixed optimization methods, there are easily large limitations, reducing the flexibility and adaptability of the soil optimization scheme. Summary of the Invention

[0006] In view of the deficiencies of the prior art, the present invention provides a method for optimizing the soil structure of poplar plantations based on the 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 realized through the following technical solutions: A method for optimizing the soil structure of poplar plantations based on the combination of biochar and organic fertilizer, including: collecting the initial soil characteristic data of the poplar plantation area, evaluating the current soil structure improvement index of the poplar plantation area, and determining the optimization method for the soil in the poplar plantation area; according to the optimization method of the soil in the poplar plantation area, and transmitting the optimization method to a preset display port for soil optimization reminder, and performing soil structure optimization on the soil in the poplar plantation area; for the poplar plantation area where the soil structure optimization is completed, conducting an evaluation of the long-term effectiveness of biochar and an evaluation of the cumulative risk of organic pollutants; according to the evaluation of the long-term effectiveness of biochar and the evaluation of the cumulative risk of organic pollutants, configuring and updating the soil structure optimization method.

[0008] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects: (1) By providing a method for optimizing the soil structure of poplar plantations based on the combination of biochar and organic fertilizer, the present invention first collects the initial soil characteristic data of the poplar plantation, evaluates the current soil structure improvement index to determine the soil optimization method. According to the optimization method, corresponding structure optimization measures are implemented, and a reminder is sent to a preset display port. Subsequently, an evaluation of the long-term effectiveness of biochar and an evaluation of the cumulative risk of organic pollutants are conducted on the poplar plantation area where the optimization is completed. Finally, the soil optimization configuration is updated based on these evaluation results. This process realizes the precise optimization and continuous improvement of the soil structure of poplar plantations, ensuring that the soil quality meets the growth requirements of poplars.

[0009] (2) By collecting the initial soil characteristic data of the poplar plantation area and evaluating the current soil structure improvement index of the poplar plantation area, the present invention can comprehensively understand the initial conditions of the soil in the poplar plantation, 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 soil structure, compactness, water and fertilizer retention capacity, etc., providing solid data support for formulating precise soil improvement plans in the future. By comparing the current soil structure improvement index with a predefined threshold, it is possible to accurately determine whether the soil needs to be improved and which improvement method is suitable. If the index is high, it indicates that the soil structure is good and only minor optimization is required; if the index is low, in-depth improvement is needed, thus avoiding blind improvement and improving the pertinence and effectiveness of soil improvement.

[0010] (3) By collecting the growth status data of each randomly sampled poplar tree in the poplar plantation area, the present invention evaluates the growth effect index of organic fertilizer for each randomly sampled poplar tree, and can quantify the impact of organic fertilizer on poplar growth into specific values. This helps to intuitively understand the actual effect of organic fertilizer in promoting poplar growth, including the impact on key growth indicators such as relative water content of leaves, 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 rate of organic fertilizer can be determined. These growth status data and growth effect indexes can sensitively reflect the growth status of poplar trees 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 poplar trees and improve the growth quality and productivity of the entire poplar plantation.

[0011] (4) By jointly optimizing the soil structure with biochar and organic fertilizer, the present invention can provide rich carbon sources and energy for soil microorganisms, promoting the reproduction and metabolic activities of soil microorganisms. Active soil microorganisms can decompose organic substances, release nutrients, synthesize soil humus, improve the ecological function of the soil, form a virtuous cycle, and further enhance the fertility and health status of the soil. This combined optimization method can improve the buffering capacity of the soil against environmental changes and external disturbances, enabling the soil to better maintain the stability of its structure and function when facing adverse environmental conditions such as drought and acid rain, reducing the adverse impact of environmental changes on poplar growth, and enhancing the ecological stability and sustainable development ability of the poplar plantation. Brief Description of the Drawings

[0012] The present invention is further described with reference to the accompanying drawings. However, the embodiments in the drawings do not constitute any limitation to the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the following drawings.

[0013] Figure 1 It is a schematic flowchart of the method of the present invention.

[0014] Figure 2 It is a flowchart for determining the soil optimization method.

[0015] Figure 3 It is a flowchart for implementing the first soil optimization method. Detailed Embodiments

[0016] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0017] Reference Figure 1 As shown, the present invention provides a method for optimizing the soil structure of a poplar plantation based on the combination of biochar and organic fertilizer, including: collecting the initial soil characteristic data of the poplar plantation area, evaluating the current soil structure improvement index of the poplar plantation area, and determining the optimization method for the soil in the poplar plantation area.

[0018] Determining the optimization method, specifically as Figure 2 shown, Figure 2 is a flow chart for determining the soil optimization method. Collect the initial soil characteristic data of the poplar plantation area, evaluate the current soil structure improvement index, and based on the comparison result between this index and the predefined threshold, determine the soil optimization method and perform corresponding operations. If the current soil structure improvement index is greater than or equal to the threshold, perform the first soil optimization method; otherwise, perform the second soil optimization method.

[0019] According to the optimization method of the soil in the poplar plantation area, transmit the optimization method to the preset display port for soil optimization reminder, and perform soil structure optimization on the soil in the poplar plantation area.

[0020] For the poplar plantation area where the soil structure optimization is completed, conduct an evaluation of the biochar persistence and an assessment of the cumulative risk of organic pollutants.

[0021] According to the evaluation of the biochar persistence and the assessment of the cumulative risk of organic pollutants, configure and update the soil structure optimization method.

[0022] Specifically, evaluate the current soil structure improvement index of the poplar plantation area. The specific evaluation process is as follows: The initial soil characteristic data of the poplar plantation area includes the fractal dimension of soil micro-aggregates in the poplar plantation area, the acoustic wave conductivity of the soil in the poplar plantation area, the shear strength value of the soil in the poplar plantation area, and the soil thermal inertia in the poplar plantation area; among them, the fractal dimension of soil micro-aggregates can be measured by a laser particle size analyzer for particle size distribution; the acoustic wave conductivity of the soil can emit stress waves through an acoustic soil compactness meter, record the arrival time and calculate the conduction rate; the shear strength value of the soil can be measured by a field direct shear instrument; the soil thermal inertia can be calculated by monitoring the change of heat flux in the soil in real time through a soil heat flux sensor.

[0023] Extract the reference fractal dimension of soil micro-aggregates and the reference acoustic wave conductivity of the soil from the soil optimization information database.

[0024] Normalize the soil shear strength value and the soil thermal inertia in the poplar plantation area respectively to obtain the normalization results. Deviate the soil acoustic wave conductivity in the poplar plantation area from the soil acoustic wave reference conductivity to obtain the deviation result. Deviate the fractal dimension of soil microaggregates in the poplar plantation area from the reference fractal dimension of soil microaggregates, and then weight-aggregate the deviation results and the normalization results in sequence to obtain the soil structure improvement potential index in the poplar plantation area. The specific analysis process is as follows: In the formula, is the soil structure improvement potential index in 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 wave conductivity in the poplar plantation area, is the soil acoustic wave reference conductivity, is the normalized value of the soil shear strength value in the poplar plantation area, is the normalized value of the 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 library, is the weight element corresponding to the soil acoustic wave 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, is the weight element corresponding to the soil thermal inertia predefined in the soil optimization information library.

[0025] It should be noted that the above fractal dimension of soil microaggregates refers to the fractal geometric parameter of the particle size distribution of soil microaggregates. The higher the fractal dimension, the more complex the soil pore network and the rougher the surface. The soil acoustic wave conductivity refers to the propagation speed of sound waves in the soil (unit: m / s), which is mainly affected by soil compactness, particle contact tightness and water content; the soil shear strength value refers to the maximum stress (kPa) that the soil resists shear failure; the soil thermal inertia refers to the ability of the soil to resist temperature fluctuations.

[0026] Among them, the weight elements corresponding to the fractal dimension of soil micro-aggregates, the weight elements corresponding to the soil acoustic conductivity, the weight elements corresponding to the soil shear strength value, and the weight elements corresponding to the soil thermal inertia are all extracted from the soil optimization information database. The mapping relationship therein can be one-to-one or many-to-one. For example, the fractal dimension of soil micro-aggregates, the soil acoustic conductivity, the soil shear strength value, and the soil thermal inertia respectively form a mapping set with the weight elements corresponding to the fractal dimension of soil micro-aggregates, the weight elements corresponding to the soil acoustic conductivity, the weight elements corresponding to the soil shear strength value, and the weight elements corresponding to the soil thermal inertia preset in the soil optimization information database. Substituting the real-time fractal dimension of soil micro-aggregates, the soil acoustic conductivity, the soil shear strength value, and the soil thermal inertia into the mapping set, the weight elements corresponding to the fractal dimension of soil micro-aggregates, the weight elements corresponding to the soil acoustic conductivity, the weight elements corresponding to the soil shear strength value, and the weight elements corresponding to the soil thermal inertia are obtained.

[0027] In this embodiment, through the multivariate analysis of the fractal dimension of soil micro-aggregates, the soil acoustic conductivity, the soil shear strength value, and the soil thermal inertia, specifically, the correlation between these parameters is considered. Both the fractal dimension of soil micro-aggregates and the soil acoustic conductivity are at appropriate levels. When the fractal dimension is too high and deviates from the reference value, the soil pore network becomes more complex. When sound waves propagate in it, more energy is lost and the conductivity is lower. As a result, the soil acoustic conductivity is extremely likely to deviate from the reference value, greatly reducing the soil structure improvement ability in the poplar plantation area. And a higher fractal dimension at an appropriate level means that the soil pores are complex and the surface is rough, which increases the contact area between soil particles, enhances the friction and biting force between particles, thereby improving the soil shear strength and increasing the soil structure improvement ability in the poplar plantation area. Similarly, for soil with a soil acoustic conductivity that is too high and deviates from the reference value, the pores between particles are usually smaller, and the heat conduction speed in it is relatively fast, and the heat is not easily stored and retained. Therefore, the soil thermal inertia is relatively low, which will also have a negative impact on the soil structure improvement ability in the poplar plantation area.

[0028] Furthermore, the optimization method of the soil in the poplar plantation area is determined. The specific determination process is as follows: The optimization method of the soil in the poplar plantation area includes the first soil optimization method and the second soil optimization method.

[0029] The soil structure improvement potential index of the poplar plantation area is verified 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, it is determined that the soil optimization method for the poplar plantation area is 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, it is determined that the soil optimization method for the poplar plantation area is the second soil optimization method, and the second soil optimization method is executed on the soil of the poplar plantation area.

[0030] When the soil structure improvement potential index of the 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 structure improvement, and there is no need for large-scale soil improvement. Only by further optimizing the soil structure can the soil quality be improved. When the soil structure improvement potential index of the poplar plantation area is less than the predefined soil structure improvement potential index threshold, it indicates that the soil structure is poor and more in-depth improvement is needed to improve the soil quality and productivity. In this case, relying solely on the application of single organic fertilizer or biochar may not achieve the ideal improvement effect, and the method of applying a combination of organic fertilizer and biochar needs to be adopted to achieve the improvement and optimization of the soil structure.

[0031] Specifically, the first soil optimization method is executed on the soil of the poplar plantation area. The specific execution process is as follows: The specific execution process of the above first soil optimization method is as Figure 3 shown, Figure 3 As shown in the first soil optimization method execution flowchart, when executing the first soil optimization method, according to the deviation ratio of the soil structure improvement potential index to the threshold, combined with factors such as the average forest age, the application amount of organic fertilizer is determined and the soil is configured. Subsequently, within the growth monitoring period, by evaluating the organic fertilizer growth effect index and comparing it with the predicted index, it is decided whether to apply biochar. If the growth effect index does not reach the predicted value, the application amount of biochar is determined according to the estimated deviation of the growth quality and the soil configuration is optimized to achieve the dynamic adjustment and precise control of the soil improvement process.

[0032] The deviation ratio of the soil structure improvement potential index of the poplar plantation area to the soil structure improvement potential index threshold is processed to obtain the first ratio of the soil structure improvement potential index of the poplar plantation area, which is mapped to the organic fertilizer application amount adaptation factor. The average forest age of the poplar plantation area is collected, and the average forest age can be obtained by averaging the forest ages of each random sample poplar extracted from the poplar planting records, and then mapped to the organic fertilizer application amount correction factor.

[0033] Couple the organic fertilizer application amount adaptation factor and the organic fertilizer application amount correction factor with the default organic fertilizer application amount to obtain the reference organic fertilizer application amount, which is used to adjust the default organic fertilizer application amount to the reference organic fertilizer application amount and configure the soil in the poplar plantation area.

[0034] The above-mentioned deviation ratio processing is specifically to perform a difference processing on the soil structure improvement current index in the poplar plantation area and the soil structure improvement current index threshold to obtain the first deviation of the soil structure improvement current index in the poplar plantation area, and perform a ratio processing with the soil structure improvement current index threshold to obtain the first ratio of the soil structure improvement current index in the poplar plantation area.

[0035] The above-mentioned mapping to obtain the organic fertilizer application amount adaptation factor is specifically to obtain the mapping set between the first ratio of the soil structure improvement current index and the organic fertilizer application amount adaptation factor from the soil optimization information database, and input the existing first ratio of the soil structure improvement current index into the mapping set to obtain the organic fertilizer application amount adaptation factor.

[0036] The above-mentioned mapping to obtain the organic fertilizer application amount correction factor is specifically to obtain the mapping set between the average forest age and the organic fertilizer application amount correction factor from the soil optimization information database, and input the existing average forest age in the poplar plantation area into the mapping set to obtain the organic fertilizer application amount correction factor.

[0037] The above-mentioned coupling of the organic fertilizer application amount adaptation factor and the organic fertilizer application amount correction factor with the default organic fertilizer application amount is specifically to multiply the organic fertilizer application amount adaptation factor and the organic fertilizer application amount correction factor with the default organic fertilizer application amount to obtain the reference organic fertilizer application amount.

[0038] According to the reference organic fertilizer application amount, obtain the mapping set between the reference organic fertilizer application amount and the cycle correction element from the soil optimization information database, input the existing reference organic fertilizer application amount into the mapping set, map to obtain the cycle correction element, and couple the preset growth monitoring cycle with the growth monitoring cycle correction element, specifically multiply the preset growth monitoring cycle with the growth monitoring cycle correction element to obtain the growth monitoring cycle.

[0039] During the growth monitoring cycle, collect the growth status data of each random sample poplar in the poplar plantation area, evaluate the organic fertilizer growth effect index of each random sample poplar, perform mean processing to obtain the organic fertilizer growth effect index in the poplar plantation area, and according to the reference organic fertilizer application amount, find the corresponding organic fertilizer growth effect prediction index, and compare it with the organic fertilizer growth effect index in the poplar plantation area to determine whether to apply biochar.

[0040] The above search yields the corresponding prediction index for the growth effect of organic fertilizer. Specifically, a mapping set between the reference application rate of organic fertilizer and the prediction index for the growth effect of organic fertilizer is obtained from the soil optimization information database. The existing reference application rate of organic fertilizer is input into the mapping set to search for the prediction index for the growth effect of organic fertilizer.

[0041] By performing a ratio processing on the current index of soil structure improvement and the threshold value, mapping to obtain the suitable application rate of organic fertilizer, and making corrections in combination with the average forest age, the application rate of organic fertilizer can be accurately determined to meet the requirements of soil improvement for poplar plantations, avoid over-application or under-application of organic fertilizer, and improve the efficiency and effect of soil improvement. At the same time, during the growth monitoring period, data on the growth status of poplars is collected, the growth effect index of organic fertilizer is evaluated, and compared with the prediction index, which can dynamically evaluate the application effect of organic fertilizer, timely determine whether biochar needs to be applied based on the comparison results, realize the dynamic adjustment and optimization of the soil improvement process, and improve the flexibility and adaptability of soil improvement.

[0042] Furthermore, the determination of whether to apply biochar is as follows: If the growth effect index of organic fertilizer in the poplar plantation area is greater than or equal to the prediction index for the growth effect of organic fertilizer, it is determined that no biochar needs to be applied, the reference application rate of organic fertilizer is maintained, and the reference application rate of organic fertilizer is uploaded to the soil optimization information database for updating the default application rate of organic fertilizer.

[0043] If the growth effect index of organic fertilizer in the poplar plantation area is less than the prediction index for the growth effect of organic fertilizer, it is determined that biochar needs to be applied. The growth effect index of organic fertilizer in the poplar plantation area is subtracted from the prediction index for the growth effect of organic fertilizer to obtain the estimated deviation of growth quality in the poplar plantation area, which is mapped to obtain the suitable application rate of biochar. According to the reference application rate of organic fertilizer, the corresponding correction factor for biochar application is found. The suitable application rate of biochar and the correction factor for biochar application are coupled. Specifically, the suitable application rate of biochar is multiplied by the correction factor for biochar application to obtain the reference application rate of biochar for configuring the soil in the poplar plantation area.

[0044] The above mapping to obtain the suitable application rate of biochar is specifically to obtain the mapping set between the estimated deviation of growth quality in the poplar plantation area and the suitable application rate of biochar from the soil optimization information database, and input the existing estimated deviation of growth quality in the poplar plantation area into the mapping set to map and obtain the suitable application rate of biochar.

[0045] The above search to obtain the corresponding correction factor for biochar application is specifically to obtain the mapping set between the reference application rate of organic fertilizer and the correction factor for biochar application from the soil optimization information database, and input the existing reference application rate of organic fertilizer into the mapping set to search for the corresponding correction factor for biochar application.

[0046] This solution clarifies under what circumstances biochar needs to be applied and how to determine the application rate of biochar, avoiding the blind application of biochar, improving the scientificity and rationality of biochar application, and further optimizing the effect of soil structure improvement. By calculating the predicted deviation of growth quality to map the appropriate application rate of biochar and making corrections in combination with the correction amount of biochar application, the application rate of biochar can be accurately adjusted according to the actual needs of the soil and poplar trees, effectively utilizing biochar resources and avoiding waste. This forms an optimized closed loop with the above-mentioned application and effect evaluation of organic fertilizer, making the soil improvement process more systematic and coherent, being able to timely adjust the next application strategy according to the evaluation results of the previous step, continuously optimizing the soil structure improvement plan, and improving the sustainability of soil improvement.

[0047] Specifically, evaluate the organic fertilizer growth effect index of each randomly sampled poplar tree. The specific evaluation process is as follows: The growth status data of each randomly sampled poplar tree in the poplar plantation area, including the deviation degree value of the relative water content of the leaves of each randomly sampled poplar tree, the deviation degree value of the net photosynthetic rate of each randomly sampled poplar tree, and the deviation degree value of the leaf chlorophyll content of each randomly sampled poplar tree; among them, the growth status data can be obtained by extracting from the monitoring report of the poplar tree. Specifically, it is the growth status data of each randomly sampled poplar tree at the end time point of the growth monitoring period.

[0048] Extract the relative appropriate water content of the leaves, the appropriate net photosynthetic rate, and the appropriate leaf chlorophyll content from the soil optimization information database.

[0049] In this embodiment, the deviation degree value is specifically obtained by respectively performing deviation processing on the relative water content of the leaves of each randomly sampled poplar tree, the net photosynthetic rate of each randomly sampled poplar tree, and the leaf chlorophyll content of each randomly sampled poplar tree with the relative appropriate water content of the leaves, the appropriate net photosynthetic rate, and the appropriate leaf chlorophyll content, so as to obtain the deviation degree value of the relative water content of the leaves of each randomly sampled poplar tree, the deviation degree value of the net photosynthetic rate of each randomly sampled poplar tree, and the deviation degree value of the leaf chlorophyll content of each randomly sampled poplar tree.

[0050] Extract the initial growth status data of each randomly sampled poplar tree in the poplar plantation area, including the initial deviation degree value of the relative water content of the leaves of each randomly sampled poplar tree, the initial deviation degree value of the net photosynthetic rate of each randomly sampled poplar tree, and the initial deviation degree value of the leaf chlorophyll content of each randomly sampled poplar tree; among them, the growth status data can be obtained by extracting from the monitoring report of the poplar tree. Specifically, it is the growth status data of each randomly sampled poplar tree at the start time point of the growth monitoring period.

[0051] In this embodiment, the deviation degree value is specifically obtained by performing deviation processing on the initial leaf relative water content, the initial net photosynthetic rate, and the initial leaf chlorophyll content of each randomly sampled poplar tree, respectively, with the leaf relative adaptation water content, the net photosynthesis adaptation rate, and the leaf chlorophyll adaptation content, to obtain the initial leaf relative water content deviation degree value, the initial net photosynthetic rate deviation degree value, and the initial leaf chlorophyll content deviation degree value of each randomly sampled poplar tree.

[0052] Perform deviation processing on the leaf relative water content deviation degree value of each randomly sampled poplar tree and the initial leaf relative water content deviation degree value of each randomly sampled poplar tree, the net photosynthetic rate deviation degree value of each randomly sampled poplar tree and the initial net photosynthetic rate deviation degree value of each randomly sampled poplar tree, and the leaf chlorophyll content deviation degree value of each randomly sampled poplar tree and the initial leaf chlorophyll content deviation degree value of each randomly sampled poplar tree, respectively, and then perform weighted aggregation in sequence to obtain the organic fertilizer growth effect index of each randomly sampled poplar tree. The specific analysis process is as follows: In the formula, is the organic fertilizer growth effect index of the j-th randomly sampled poplar tree, where j is the code of each randomly sampled poplar tree, , M is the total amount of randomly sampled poplar trees, is the first sub-index of the organic fertilizer growth effect of the j-th randomly sampled poplar tree, is the second sub-index of the organic fertilizer growth effect of the j-th randomly sampled poplar tree, is the leaf relative water content deviation degree value of the j-th randomly sampled poplar tree, is the initial leaf relative water content deviation degree value of the j-th randomly sampled poplar tree, is the leaf relative adaptation water content, is the net photosynthetic rate deviation degree value of the j-th randomly sampled poplar tree, is the initial net photosynthetic rate deviation degree value of the j-th randomly sampled poplar tree, is the net photosynthesis adaptation rate, is the leaf chlorophyll content deviation degree value of the j-th randomly sampled poplar tree, is the initial leaf chlorophyll content deviation degree value of the j-th randomly sampled poplar tree, is the leaf chlorophyll adaptation content, is the weight element corresponding to the leaf relative water content deviation degree value predefined in the soil optimization information database, It is the weight element corresponding to the predefined deviation degree value of net photosynthetic rate in the soil optimization information database. It is the weight element corresponding to the predefined deviation degree value of leaf chlorophyll content in the soil optimization information database. It is the weight element corresponding to the predefined deviation degree value of initial relative water content of leaves in the soil optimization information database. It is the weight element corresponding to the predefined deviation degree value of initial net photosynthetic rate in the soil optimization information database. It is the weight element corresponding to the predefined deviation degree value of initial leaf chlorophyll content in the soil optimization information database. It is the adjustment factor corresponding to the growth effect index of organic fertilizer.

[0053] It should be noted that the adjustment factor corresponding to the above-mentioned growth effect index of organic fertilizer refers to the variable of the adjustment factor that needs to be incorporated to control environmental heterogeneity when evaluating the independent effect of organic fertilizer on the growth of poplar. It helps to improve the accuracy of the evaluation of the effect of organic fertilizer and reduce the environmental dependence of the effect of organic fertilizer. Specifically, the adjustment factor corresponding to the growth effect index of organic fertilizer can be obtained by: real-time extracting the soil structure improvement potential index of the poplar plantation area at each time period of the growth monitoring cycle, performing mean processing to obtain the mean value of the soil structure improvement potential index of the poplar plantation area, obtaining the mapping set between the mean value of the soil structure improvement potential index and the adjustment factor from the soil optimization information database, and inputting the existing mean value of the soil structure improvement potential index of the poplar plantation area into the mapping set to map and obtain the adjustment factor corresponding to the growth effect index of organic fertilizer.

[0054] The mean value of the soil structure improvement potential index reflects the overall soil structure improvement potential and quality status of the poplar plantation area. The mean value of the soil structure improvement potential index can be used 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 different 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.

[0055] Among them, the weight element corresponding to the deviation degree value of relative water content of leaves, the weight element corresponding to the deviation degree value of net photosynthetic rate, the deviation degree value of leaf chlorophyll content, the weight element corresponding to the deviation degree value of initial relative water content of leaves, the weight element corresponding to the deviation degree value of initial net photosynthetic rate, and the deviation degree value of initial leaf chlorophyll content are all extracted from the soil optimization information database. The mapping relationship among them can be one-to-one or many-to-one. For example, the deviation of relative water content of leaves forms a mapping set with the weight element corresponding to the predefined deviation degree value of relative water content of leaves in the soil optimization information database, and the real-time deviation degree value of relative water content of leaves is brought into the mapping set to obtain the weight element corresponding to the deviation degree value of relative water content of leaves.

[0056] In this embodiment, through the multivariate analysis of the relative water content of leaves, net photosynthetic rate, and leaf chlorophyll content, specifically considering the correlation between these parameters, when the relative water content of leaves is too high and deviates from the reference value, it may lead to excessive water in the cells, cell swelling, and the stability of the cell membrane may be affected. At this time, excessive water may dilute the substance concentration in the cells, affect the enzyme activity and metabolic process related to photosynthesis, thereby reducing the net photosynthetic rate and causing it to deviate from the reference value, so as to reduce the growth effect of organic fertilizer; at the same time, excessive water may lead to poor air permeability of the leaf tissue, affect the diffusion of oxygen, and further affect the normal progress of photosynthesis. In addition, too high relative water content of leaves may inhibit the synthesis of chlorophyll or accelerate the degradation rate of chlorophyll, resulting in a decrease in leaf chlorophyll content. When the relative water content of leaves is insufficient, the water in the cells decreases, which will cause the stomata to close to reduce water loss. The closure of stomata will limit the entry of carbon dioxide, directly affecting the dark reaction of photosynthesis and also resulting in a decrease in the net photosynthetic rate.

[0057] Furthermore, a second soil optimization method is implemented for the soil in the poplar plantation area. The specific implementation process is as follows: The deviation ratio of the soil structure improvement present force index in the poplar plantation area to the threshold of the soil structure improvement present force index is processed to obtain the second ratio of the soil structure improvement present force index in the poplar plantation area. The corresponding 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 the soil in the poplar plantation area is jointly configured.

[0058] The above-mentioned matching of the adaptation ratio of the biochar-organic fertilizer combination is specifically to match the second ratio of the soil structure improvement present force index in the poplar plantation area with the adaptation ratio of the biochar-organic fertilizer combination corresponding to each predefined second ratio interval of the soil structure improvement present force index, determine the specific interval of the second ratio of the soil structure improvement present force index in the poplar plantation area, and obtain the second ratio of the soil structure improvement present force index in the poplar plantation area corresponding to this interval.

[0059] After the joint configuration of the soil in the poplar plantation area is completed, during the implementation adjustment period, the soil organic matter in the poplar plantation area is extracted. 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.

[0060] When the soil organic matter in the poplar plantation area does not belong to the soil organic matter reference range, adjust the proportion of the biochar-organic fertilizer combination.

[0061] Match the adaptation proportion of the biochar-organic fertilizer combination according to the second proportion of the soil structure improvement potential index. It can accurately adjust the combined application proportion of biochar and organic fertilizer for soils with different improvement potentials, give full play to the advantages of both, and improve the effect and efficiency of soil improvement. During the implementation of the adjustment cycle, by comparing the soil organic matter with the predefined reference range, the abnormal changes in the soil organic matter content can be detected in a timely manner, and the proportion of the biochar-organic fertilizer combination can be adjusted accordingly to maintain the soil organic matter content within an appropriate range and ensure the soil fertility and ecological functions. This way of dynamically adjusting the combined application proportion according to the soil organic matter helps to enhance the stability of soil improvement, avoid the re-degradation of soil structure caused by large fluctuations in soil organic matter content, and ensure the long-term effect of soil improvement.

[0062] Specifically, the adjustment of the proportion of the biochar-organic fertilizer combination is as follows: Extract the maximum value and the minimum value of the soil organic matter reference range.

[0063] If the soil organic matter in the poplar plantation area is less than the minimum value of the soil organic matter reference range, perform a difference operation on the soil organic matter in the poplar plantation area and the minimum value of the soil organic matter reference range to obtain the minimum value deviation of the soil organic matter in the poplar plantation area, and map it to obtain the organic fertilizer proportion adjustment factor, which is used to increase the proportion of organic fertilizer in the biochar-organic fertilizer combination to obtain the corrected proportion 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 range, then match the biochar proportion adjustment factor according to the maximum value deviation of the soil organic matter in the poplar plantation area, which is used to reduce the proportion of organic fertilizer in the biochar-organic fertilizer combination to obtain the corrected proportion of the biochar-organic fertilizer combination, and reconfigure the soil in the poplar plantation area based on the corrected proportion of the biochar-organic fertilizer combination.

[0064] When the soil organic matter is less than the minimum value of the soil organic matter reference range, it indicates that the soil organic matter content is too low. Organic fertilizer is one of the important sources to increase soil organic matter. Increasing the proportion of organic fertilizer in the biochar-organic fertilizer combination can quickly supplement organic matter to the soil, improve the soil fertility status, promote the formation and stability of soil aggregates, and optimize the soil structure. For example, components such as humus in organic fertilizer can combine with soil particles to increase the water retention and air permeability of the soil.

[0065] When the soil organic matter is greater than the maximum value of the soil organic matter reference range, it indicates that the soil organic matter content is too high. Biochar itself has relatively stable chemical properties and can exist in the soil for a long time after being applied. Reducing the proportion of organic fertilizer in the biochar-organic fertilizer combination and increasing the proportion of biochar accordingly can appropriately reduce the accumulation rate of organic matter in the soil and prevent problems that may be caused by excessive accumulation of soil organic matter, such as poor soil aeration. At the same time, it can also avoid the waste of biochar resources.

[0066] Example: Suppose the default ratio of the biochar-organic fertilizer combination is 5:5, and the suitable ratio of the biochar-organic fertilizer combination is 4:6. Configure the soil in the poplar plantation area according to this ratio (40% biochar and 60% organic fertilizer), and extract and monitor the soil organic matter during the implementation adjustment period.

[0067] Suppose the mapped adjustment factor for the proportion of organic fertilizer is +10%. Therefore, the proportion of organic fertilizer in the new combination is adjusted to 60% + 10% = 70%, and the corresponding proportion of biochar is adjusted to 30%. Based on the corrected ratio (30% biochar and 70% organic fertilizer), reconfigure the soil in the poplar plantation area to increase the soil organic matter content and optimize the soil structure.

[0068] In this way, the soil organic matter content can be more accurately controlled within an appropriate range. This helps to maintain good physical, chemical, and biological properties of the soil, providing a stable and high-quality soil environment for the growth of poplars. Reasonably adjusting 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 resource waste. Different initial soil conditions and poplar growth stages may have different requirements for soil organic matter. By dynamically adjusting the ratio of the combination, the soil improvement measures can be made more adaptable and flexible, improving the success rate and sustainability of soil improvement.

[0069] Furthermore, for the evaluation of the long-term effectiveness of biochar, the specific evaluation process is as follows: During the application and planting cycle, the content of stable carbon 14 C in biochar is measured in real time, where 14 the content of 14 C can be monitored and obtained by an accelerator mass spectrometer. Based on the content of stable

[0070] The above-mentioned application planting cycle specifically refers to a period of time during which the biochar-organic fertilizer combination takes effect. If the long-term effectiveness of biochar decreases during the application planting cycle, additional application of biochar is required. If the long-term effectiveness of biochar decreases after the end of the application planting cycle, it is a normal function of the biochar-organic fertilizer combination, and no additional application of biochar is needed.

[0071] The actual application amount of biochar is expressed as the required application amount of biochar corresponding to its proportion in the biochar-organic fertilizer combination. It can be obtained by extracting from the configuration records of the poplar plantation area. The residual amount of biochar is expressed as the remaining amount after it is applied to the soil, reflecting its long-term effectiveness. It represents the remaining quantity after the biochar has played its role.

[0072] The above-mentioned residual amount of biochar found is specifically obtained from the soil optimization information database for the stability 14 mapping set between the content of C and the residual amount of biochar, and inputting the existing stability 14 content of C into the mapping set to find the residual amount of biochar.

[0073] The above-mentioned residual amount threshold of biochar obtained by matching is specifically to match the growth effect index of organic fertilizer in the poplar plantation area with the residual amount thresholds corresponding to each predefined interval of the growth effect index of organic fertilizer, determine the specific interval of the growth effect index of organic fertilizer in the poplar plantation area, and obtain the residual amount threshold of biochar corresponding to this interval.

[0074] The growth effect index of organic fertilizer reflects the promoting effect of organic fertilizer on the growth of poplars, while the residual amount threshold of biochar is related to the continuous supporting ability of the soil for the growth of poplars. Generally speaking, when the growth effect index of organic fertilizer is relatively high, it indicates that the soil environment and nutrient supply conditions are good. At this time, not much biochar needs to be consumed to maintain the soil's supporting ability for the growth of poplars, so the corresponding residual amount threshold of biochar will be relatively high; on the contrary, if the growth effect index of organic fertilizer is relatively low, it indicates that there may be problems with soil fertility or structure, and more biochar needs to be consumed to improve the soil conditions to better support the growth of poplars, so the corresponding residual amount threshold of biochar will be relatively low. There is a correlation between the two to match the application amount of biochar according to the soil fertility status and the growth requirements of poplars.

[0075] Matching the residual amount threshold of biochar based on the growth effect index of organic fertilizer can achieve precise regulation of the application amount of biochar. This can ensure that, on the premise of meeting the growth requirements of poplars, biochar resources are rationally utilized, avoiding waste of resources or potential soil ecological problems caused by excessive application of biochar. At the same time, it also helps to maintain the long-term fertility and stability of the soil, optimize the effect of soil structure improvement, and improve the sustainability of soil improvement measures.

[0076] Obtain the starting time point of biochar application, where the starting time point is specifically extracted from the configuration record of the poplar plantation area. When the residual amount of biochar is less than the residual amount threshold of biochar, it is determined that the persistence of biochar decreases. Obtain the time point when the persistence of biochar decreases. Record the time interval between the starting time point of biochar application and the time point when the persistence of biochar decreases as the persistence maintenance duration of biochar. Map to obtain the supplementary amount of biochar. According to the actual application amount of biochar, match to obtain the supplementary amount correction element of biochar. Couple the corrected supplementary amount of biochar with the supplementary amount correction element of biochar. Specifically, multiply the corrected supplementary amount of biochar by the supplementary amount correction element of biochar to obtain the corrected supplementary amount of biochar. At the time point when the persistence of biochar decreases, optimize the configuration of the soil in the poplar plantation area based on the corrected supplementary amount of biochar.

[0077] The above-mentioned mapping to obtain the supplementary amount of biochar is specifically to obtain the mapping set between the persistence maintenance duration of biochar and the supplementary amount of biochar from the soil optimization information database. Input the existing persistence maintenance duration of biochar into the mapping set to find the supplementary amount of biochar.

[0078] The above-mentioned matching to obtain the supplementary amount correction element of biochar is specifically to match the actual application amount of biochar with the supplementary amount correction elements corresponding to each predefined actual application amount interval, determine the specific interval of the actual application amount of biochar, and obtain the supplementary amount correction element of biochar corresponding to this interval.

[0079] By measuring the content of stable carbon 14 C in biochar in real time, the residual amount and persistence maintenance duration of biochar in the soil can be accurately understood, so as to determine the best time for supplementary application of biochar, avoid blind application, and improve the efficiency and effect of soil improvement. And according to the evaluation results of biochar persistence, the supplementary ratio and supplementary correction ratio of biochar can be scientifically determined, rationally allocate biochar resources, avoid waste of resources, which helps to ensure the long-term stability and sustainability of soil improvement, maintain the good structure and fertility of the soil, provide guarantee for the continuous growth of poplars, and avoid the re-degradation of soil structure caused by the decrease of biochar persistence.

[0080] Specifically, the cumulative risk assessment of organic pollutants, the specific assessment process is as follows: During the application planting cycle, the polycyclic aromatic hydrocarbon content of the soil is collected in real time. The polycyclic aromatic hydrocarbon content can be monitored by a gas chromatography-mass spectrometry instrument and compared with the predefined polycyclic aromatic hydrocarbon defined content. When the polycyclic aromatic hydrocarbon content of the soil is less than or equal to the polycyclic aromatic hydrocarbon defined content, the cumulative risk assessment of organic pollutants is continuously carried out. When the polycyclic aromatic hydrocarbon content of the soil is greater than the polycyclic aromatic hydrocarbon defined content, the polycyclic aromatic hydrocarbon content of the soil is processed for proportion calculation with the polycyclic aromatic hydrocarbon defined content to obtain the proportion deviation of the polycyclic aromatic hydrocarbon content of the soil, and it is compared with the predefined polycyclic aromatic hydrocarbon content deviation proportion threshold: If the proportion deviation of the polycyclic aromatic hydrocarbon content of the soil is less than or equal to the polycyclic aromatic hydrocarbon content deviation proportion threshold, the application amount of the biochar loaded with iron oxide is mapped according to the proportion deviation of the polycyclic aromatic hydrocarbon content of the soil, and the soil in the poplar plantation area is configured and optimized based on the application amount of the biochar loaded with iron oxide.

[0081] The above-mentioned mapping to obtain the application amount of the biochar loaded with iron oxide is specifically to obtain the mapping set between the proportion deviation of the polycyclic aromatic hydrocarbon content of the soil and the application amount of the biochar loaded with iron oxide from the soil optimization information database, and input the existing proportion deviation of the polycyclic aromatic hydrocarbon content of the soil into the mapping set to obtain the application amount of the biochar loaded with iron oxide.

[0082] If the proportion deviation of the polycyclic aromatic hydrocarbon content of the soil is greater than the polycyclic aromatic hydrocarbon content deviation proportion threshold, the application proportion of the biochar loaded with iron oxide is mapped according to the proportion deviation of the polycyclic aromatic hydrocarbon content of the soil, which is used to correct the proportion of the biochar in the biochar-organic fertilizer combination, add the application proportion of the biochar loaded with iron oxide, maintain the biochar-organic fertilizer combination proportion, and complete the configuration optimization of the soil in the poplar plantation area based on the biochar-organic fertilizer combination proportion.

[0083] Example, assume that the proportion of biochar in the original biochar-organic fertilizer combination is 40% and the proportion of organic fertilizer is 60%. The application proportion of the biochar loaded with iron oxide is 15%. That is, the new biochar application proportion is 25% + 15% = 40%. Correspondingly, the proportion of organic fertilizer remains 60% unchanged. Configure the soil in the poplar plantation area with this new proportion (biochar proportion 25% + biochar loaded with iron oxide proportion 15%, organic fertilizer proportion 60%) to complete the proportion adjustment of the combination.

[0084] By collecting in real time the content of polycyclic aromatic hydrocarbons, an organic pollutant index of the soil, and comparing it with a predefined defined content, the accumulation of organic pollutants in the soil can be detected in a timely manner, and measures can be taken in advance to prevent the expansion of pollution risks and protect the soil ecological environment. Based on the results of the cumulative risk assessment of organic pollutants, reasonably adjust the ratio of the biochar-organic fertilizer combination or add biochar loaded with iron oxides, optimize the fertilization strategy, reduce the further accumulation of organic pollutants, and improve the safety and stability of the soil. Prevent the excessive accumulation of organic pollutants in the soil, avoid adverse effects on soil microorganisms, plant growth, and the surrounding ecological environment, and ensure the health and safety of the poplar plantation ecosystem.

[0085] The above content is only an example and illustration of the structure of the present invention. Those skilled in the art of the present technology can make various modifications or supplements to the described specific embodiments or use similar methods for substitution. As long as they do not deviate from the structure of the invention or exceed the scope defined by the present invention, they should fall within the protection scope of the present invention.

Claims

1. A method for optimizing the soil structure of a poplar plantation based on the combination of biochar and organic fertilizer, characterized in that Including: Collect the initial soil characteristic data of the poplar plantation area, evaluate the soil structure improvement potential index of the poplar plantation area, and determine the optimization method of the soil in the poplar plantation area; According to the optimization method of the soil in the poplar plantation area, and transmit the optimization method to the preset display port for soil optimization reminder, and perform structure optimization on the soil in the poplar plantation area; For the poplar plantation area where the soil structure optimization is completed, conduct an evaluation of the long-term effectiveness of biochar and an assessment of the cumulative risk of organic pollutants; According to the evaluation of the long-term effectiveness of biochar and the assessment of the cumulative risk of organic pollutants, configure and update the soil structure optimization method.

2. The method for optimizing the soil structure of a poplar plantation based on the combination of biochar and organic fertilizer according to claim 1, wherein: The specific evaluation process of the soil structure improvement potential index of the poplar plantation area is as follows: The initial soil characteristic data of the poplar plantation area includes the fractal dimension of soil microaggregates in the poplar plantation area, the soil acoustic 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; Extract the reference fractal dimension of soil microaggregates and the reference acoustic conductivity of soil from the soil optimization information database; Normalize the soil shear strength value and the soil thermal inertia in the poplar plantation area respectively to obtain the normalization result, perform deviation processing on the soil acoustic conductivity in the poplar plantation area and the reference acoustic conductivity of soil to obtain the deviation result, perform deviation processing on the fractal dimension of soil microaggregates in the poplar plantation area and the reference fractal dimension of soil microaggregates, and then perform weighted aggregation on the deviation results and the normalization results in sequence to obtain the soil structure improvement potential index of the poplar plantation area.

3. The method for optimizing the soil structure of a poplar plantation based on the combination of biochar and organic fertilizer according to claim 1, wherein: The specific determination process of the optimization method of the soil in the poplar plantation area is as follows: The optimization method of the soil in the poplar plantation area includes the first soil optimization method and the second soil optimization method; Verify the soil structure improvement potential index of the poplar plantation area with 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, then determine that the optimization method of the soil in the poplar plantation area is the first soil optimization method, and perform the first soil optimization method on the soil in 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, then determine that the optimization method of the soil in the poplar plantation area is the second soil optimization method, and perform the second soil optimization method on the soil in the poplar plantation area.

4. The method for optimizing the soil structure of a poplar plantation based on the combination of biochar and organic fertilizer according to claim 3, wherein: The specific implementation process of the first soil optimization method for the soil in the poplar plantation area is as follows: Perform deviation ratio processing on the soil structure improvement potential index of the poplar plantation area and the soil structure improvement potential index threshold to obtain the first ratio of the soil structure improvement potential index of the poplar plantation area, map it to obtain the organic fertilizer application amount adaptation factor, collect the average forest age of the poplar plantation area, and map it to obtain the organic fertilizer application amount correction factor; Couple the organic fertilizer application amount adaptation factor and the organic fertilizer application amount correction factor with the default organic fertilizer application amount to obtain the reference organic fertilizer application amount, which is used to adjust the default organic fertilizer application amount to the reference organic fertilizer application amount and configure the soil in the poplar plantation area; Map the periodic correction element according to the reference organic fertilizer application amount, and couple the preset growth monitoring period with the growth monitoring period correction element to obtain the growth monitoring period; During the growth monitoring period, collect the growth status data of each randomly sampled poplar tree in the poplar plantation area, evaluate the organic fertilizer growth effect index of each randomly sampled poplar tree, perform mean processing to obtain the organic fertilizer growth effect index of the poplar plantation area, and find the corresponding organic fertilizer growth effect prediction index according to the reference organic fertilizer application amount. Compare it with the organic fertilizer growth effect index of the poplar plantation area to determine whether to apply biochar.

5. The method for optimizing the soil structure of a poplar plantation based on the combination of biochar and organic fertilizer according to claim 4, characterized in that: The 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 there is no need to apply biochar, maintain the reference organic fertilizer application amount, and upload the reference organic fertilizer application amount to the soil optimization information database for updating the default organic fertilizer application amount; 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 subtract the organic fertilizer growth effect index of the poplar plantation area from the organic fertilizer growth effect prediction index to obtain the estimated growth quality deviation of the poplar plantation area. Map the corresponding biochar application amount, find the corresponding biochar application correction factor according to the reference organic fertilizer application amount, and couple the biochar application amount with the biochar application correction factor to obtain the reference biochar application amount to configure the soil in the poplar plantation area.

6. The method for optimizing the soil structure of a poplar plantation based on the combination of biochar and organic fertilizer according to claim 4, characterized in that: The process of evaluating the organic fertilizer growth effect index of each randomly sampled poplar tree is as follows: The growth status data of each randomly sampled poplar tree in the poplar plantation area includes the deviation degree value of the relative water content of the leaves of each randomly sampled poplar tree, the deviation degree value of the net photosynthetic rate of each randomly sampled poplar tree, and the deviation degree value of the chlorophyll content of the leaves of each randomly sampled poplar tree; Extract the initial growth status data of each randomly sampled poplar tree in the poplar plantation area, including the initial deviation degree value of the relative water content of the leaves of each randomly sampled poplar tree, the initial deviation degree value of the net photosynthetic rate of each randomly sampled poplar tree, and the initial deviation degree value of the chlorophyll content of the leaves of each randomly sampled poplar tree; Perform deviation processing on the deviation degree value of the relative water content of the leaves of each randomly sampled poplar tree and the initial deviation degree value of the relative water content of the leaves of each randomly sampled poplar tree, the deviation degree value of the net photosynthetic rate of each randomly sampled poplar tree and the initial deviation degree value of the net photosynthetic rate of each randomly sampled poplar tree, and the deviation degree value of the chlorophyll content of the leaves of each randomly sampled poplar tree and the initial deviation degree value of the chlorophyll content of the leaves of each randomly sampled poplar tree, and then perform weighted aggregation in sequence to obtain the organic fertilizer growth effect index of each randomly sampled poplar tree.

7. The method for optimizing the soil structure of a poplar plantation based on the combination of biochar and organic fertilizer according to claim 3, characterized in that: The specific implementation process of performing the second soil optimization method on the soil in the poplar plantation area is as follows: The deviation ratio of the soil structure improvement presentability index in the poplar plantation area to the soil structure improvement presentability index threshold is processed to obtain the second ratio of the soil structure improvement presentability index in the poplar plantation area, and the adaptation ratio of the biochar-organic fertilizer combination is obtained, which is used to adjust the default ratio of the biochar-organic fertilizer combination to the adaptation ratio of the biochar-organic fertilizer combination, and the soil in the poplar plantation area is jointly configured; After the joint configuration of the soil in the poplar plantation area is completed, 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 for updating the default ratio of the biochar-organic fertilizer combination; When the soil organic matter in the poplar plantation area does not belong to the soil organic matter reference interval, the ratio of the biochar-organic fertilizer combination is adjusted.

8. The method for optimizing the soil structure of a poplar plantation based on the combination of biochar and organic fertilizer according to claim 7, wherein: The adjustment of the ratio of the biochar-organic fertilizer combination is specifically carried out as follows: Extract the maximum value and the 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 difference between the soil organic matter in the poplar plantation area and the minimum value of the soil organic matter reference interval is processed to obtain the minimum value deviation of the soil organic matter in the poplar plantation area, and the organic fertilizer proportion adjustment factor is mapped, which is used to increase the proportion of organic fertilizer in the biochar-organic fertilizer combination to obtain the corrected 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 proportion adjustment factor is obtained according to the maximum value deviation of the soil organic matter in the poplar plantation area, which is used to reduce the proportion of organic fertilizer in the biochar-organic fertilizer combination to obtain the corrected ratio of the biochar-organic fertilizer combination. Based on the corrected ratio of the biochar-organic fertilizer combination, the soil in the poplar plantation area is reconfigured.

9. The method for optimizing the soil structure of a poplar plantation based on the combination of biochar and organic fertilizer according to claim 1, wherein: The specific evaluation process of the biochar persistence evaluation is as follows: During the application planting cycle, the stable carbon in biochar is measured in real time 14 The content of C is determined, and based on the content of stable 14 C, the residual amount of biochar is found. According to the organic fertilizer growth effect index in the poplar plantation area, the residual amount threshold of biochar is matched; Obtain the start time point of biochar application, and when the residual amount of biochar is less than the residual amount threshold of biochar, it is determined that the persistence of biochar decreases. Obtain the time point of biochar persistence decrease, and record the time interval between the start time point of biochar application and the time point of biochar persistence decrease as the persistence maintenance duration of biochar, map to obtain the supplementary amount of biochar, match the supplementary amount correction element of biochar according to the actual application amount of biochar, couple the corrected supplementary amount of biochar with the supplementary amount correction element of biochar to obtain the corrected supplementary amount of biochar, and optimize the configuration of the soil in the poplar plantation area based on the corrected supplementary amount of biochar at the time point of biochar persistence decrease.

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

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