Method for analyzing the effect of soil microorganisms on the rhizosphere of crops

Abstract

The application discloses a kind of analysis methods of the influence of soil microorganism to crop rhizosphere, it is related to rhizosphere influence analysis technical field, for solving the problem of identifying high-risk nitrogen loss state probability reduction, by monitoring soil moisture content to assess water saturation state and saturation duration, collection redox potential and calculate the rate of decline, combined with saturation duration to crop rhizosphere state classification, when rhizosphere anoxia, detect the nitrous oxide concentration and nitrate nitrogen content of the land to be measured, based on nitrate nitrogen content analysis nitrogen consumption trend of the land to be measured, combined with nitrous oxide concentration generates the response coefficient of denitrifying bacteria of the land to be measured, according to the response coefficient of denitrifying bacteria, the rhizosphere nitrogen loss grade of the land to be measured is formulated, when rhizosphere nitrogen loss grade is high, drainage treatment is carried out to the land to be measured, the glucose content of crop rhizosphere in the land to be measured is collected to determine whether to apply denitrifying bacteria inhibitor to the land to be measured, accurately identify high-risk nitrogen loss state.

Description

Technical Field

[0001] This invention relates to the field of rhizosphere influence analysis technology, and more specifically, to a method for analyzing the influence of soil microorganisms on crop rhizosphere. Background Technology

[0002] The rhizosphere is a key area for the interaction between plant roots and soil microbial communities. Its biochemical reaction characteristics directly affect crop nutrient absorption efficiency, root metabolic activity, and soil fertility stability. When the soil is in a state of long-term water saturation, the oxygen content in the soil pores decreases, which leads to increased activity of denitrifying bacteria, thereby promoting the reduction of nitrate nitrogen to nitrous oxide or nitrogen gas, resulting in rhizosphere nitrogen loss.

[0003] The existing technology has the following shortcomings:

[0004] Currently, existing technologies lack multi-parameter coupled monitoring and quantitative analysis mechanisms for the dynamic response of soil microorganisms to crop rhizosphere nitrogen cycling. This makes it difficult to reflect the real-time correlation between water saturation, redox potential change rate, and denitrifying bacteria activity, thus affecting the accuracy of scientific assessment and regulation of rhizosphere nitrogen transformation. Consequently, the probability of identifying high-risk nitrogen loss states decreases, and the risk of nitrogen loss increases. Therefore, this paper proposes an analytical method for the impact of soil microorganisms on crop rhizosphere.

[0005] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] To overcome the aforementioned deficiencies of the prior art, embodiments of the present invention provide an analytical method for the influence of soil microorganisms on crop rhizosphere. This method utilizes a multi-parameter comprehensive analysis model constructed by soil moisture monitoring, dynamic calculation of redox potential, and denitrifying bacteria response coefficients to address the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for analyzing the effects of soil microorganisms on crop rhizosphere, comprising the following steps:

[0008] Step S1: Monitor the soil moisture content of the land to be tested, assess whether the land to be tested is in a water saturation state based on the soil moisture content, count the duration of saturation of the land to be tested in a water saturation state, and collect the redox potential of the land to be tested.

[0009] Step S2: Calculate the potential decrease rate based on the redox potential, and classify the rhizosphere state of the test land according to the duration of saturation. When the rhizosphere state of the crop is hypoxic, detect the nitrous oxide concentration and nitrate nitrogen content of the test land.

[0010] Step S3: Analyze the nitrogen consumption trend of the land to be tested based on the nitrate nitrogen content, generate the denitrifying bacteria response coefficient of the land to be tested by combining the nitrous oxide concentration, and determine the rhizosphere nitrogen loss level of the land to be tested based on the denitrifying bacteria response coefficient.

[0011] Step S4: When the rhizosphere nitrogen loss level is high, drain the land to be tested. After draining, collect the glucose content in the rhizosphere of the crops in the land to be tested. Determine whether to apply denitrifying bacteria inhibitors to the land to be tested based on the glucose content.

[0012] In a preferred embodiment, in step S1, soil moisture sensors are deployed in the land to be tested at a preset sampling depth to monitor the soil moisture content of the land to be tested.

[0013] Soil moisture content is the volume ratio of water contained in a unit volume of soil.

[0014] Soil moisture content is used to determine whether the land to be tested is in a water-saturated state. A water-saturated state refers to a state in which the soil pores are filled with water and air is expelled.

[0015] When the soil moisture content is greater than or equal to the preset soil saturation threshold, the land to be tested is determined to be in a state of water saturation.

[0016] Otherwise, the land to be tested is determined to be in a state of unsaturated moisture.

[0017] In a preferred embodiment, in step S1, when it is determined that the land to be tested is in a state of water saturation, the duration of the water saturation state is statistically analyzed to obtain the saturation duration.

[0018] The potential difference between the measuring electrode and the reference electrode of the potential measuring device is recorded by a high impedance potentiometer, and the potential difference is used as the redox potential of the soil to be tested.

[0019] In a preferred embodiment, in step S2, the redox potential within a continuous monitoring time series is obtained, and the potential decrease rate is calculated based on the redox potential at two adjacent monitoring time points.

[0020] The absolute value of the potential decrease rate and the saturation duration are standardized to obtain the potential decrease factor and the duration factor.

[0021] The hypoxia discrimination index of the land under test is obtained by weighted summation of the potential drop factor and the duration factor.

[0022] In a preferred embodiment, in step S2, when the hypoxia discrimination index is greater than or equal to the preset hypoxia discrimination threshold, the rhizosphere state of the crop in the test land is determined to be hypoxic.

[0023] Conversely, when the hypoxia discrimination index is less than the preset hypoxia discrimination threshold, the rhizosphere state of the crop in the test land is determined to be oxygenated.

[0024] When the rhizosphere of the crop in the test land is determined to be hypoxic, the concentration of nitrous oxide is collected by an infrared gas sensor deployed in the test land.

[0025] Nitrate nitrogen content is collected by a nitrate nitrogen biosensor deployed in the rhizosphere soil layer of the land to be tested. The nitrate nitrogen content is a continuously collected time series value, forming nitrate nitrogen content data.

[0026] In a preferred embodiment, in step S3, after sorting the nitrate nitrogen content data of the land to be tested in chronological order, each nitrate nitrogen content and the corresponding collection time are input into the least squares regression model for fitting processing to obtain the fitting intercept and fitting slope.

[0027] The absolute value of the fitted slope is used as the nitrogen consumption trend of the land under test.

[0028] In a preferred embodiment, in step S3, the nitrogen consumption trend and nitrous oxide concentration are standardized to obtain the nitrogen consumption trend coefficient and nitrous oxide coefficient, respectively.

[0029] The product of the nitrogen consumption trend coefficient, the nitrous oxide coefficient, and the preset adjustment factor is used as the denitrifying bacteria response coefficient.

[0030] If the response coefficient of denitrifying bacteria is greater than the preset denitrifying bacteria coefficient threshold, the rhizosphere nitrogen loss level of the tested land is judged to be high.

[0031] Conversely, if the rhizosphere nitrogen loss level of the tested land is determined to be low.

[0032] In a preferred embodiment, in step S4, when the rhizosphere nitrogen loss level is high, the land to be tested is drained.

[0033] After drainage treatment, the sampling period was preset and divided into multiple sampling times. The glucose content of the crop rhizosphere in the soil to be tested was collected by glucose oxidase immobilized electrode.

[0034] The glucose content at each sampling time is sorted in chronological order. If the glucose content at the current sampling time is higher than the glucose content at the previous and next sampling times, then the current sampling time is recorded as a local peak point.

[0035] Conversely, the current sampling time is not recorded.

[0036] In a preferred embodiment, in step S4, the average value of the glucose content corresponding to each local peak point is taken to obtain the peak average content.

[0037] Within a preset sampling period, the number of local peak points is counted as the number of glucose peaks, and the product of the average peak content and the number of glucose peaks is used as the glucose pulse index.

[0038] If the glucose pulse index is greater than the preset glucose pulse threshold, it is determined that a denitrifying bacteria inhibitor has been applied to the land to be tested.

[0039] Conversely, no denitrifying bacteria inhibitors are applied to the land to be tested.

[0040] The technical effects and advantages of this invention are as follows:

[0041] This invention assesses the water saturation state of a test land by monitoring its soil moisture content and duration. It also collects the redox potential of the test land and calculates the rate of potential decrease. Based on the duration of saturation, the rhizosphere state of the test land is classified. When the rhizosphere state is hypoxic, the concentrations of nitrous oxide and nitrate nitrogen in the test land are measured. The nitrogen consumption trend of the test land is analyzed based on the nitrate nitrogen content. A denitrifying bacteria response coefficient is generated based on the nitrous oxide concentration. The rhizosphere nitrogen loss level of the test land is determined according to the denitrifying bacteria response coefficient. When the rhizosphere nitrogen loss level is high, the test land is drained. The glucose content in the rhizosphere of the test land is collected to determine whether denitrifying bacteria inhibitors should be applied. This achieves dynamic quantitative analysis of the rhizosphere denitrification process, accurately identifies high-risk nitrogen loss states, and provides a basis for crop rhizosphere nitrogen management and microbial activity regulation. Attached Figure Description

[0042] Figure 1 This is a flowchart illustrating the implementation of an analytical method for the effects of soil microorganisms on crop rhizosphere according to the present invention.

[0043] Figure 2 This is a schematic diagram illustrating the steps of an analytical method for the effects of soil microorganisms on crop rhizosphere according to the present invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] This invention assesses the water saturation state of a test land by monitoring its soil moisture content and duration. It also collects the redox potential of the test land and calculates the rate of potential decrease. Based on the duration of saturation, the rhizosphere state of the test land is classified. When the rhizosphere state is hypoxic, the concentrations of nitrous oxide and nitrate nitrogen in the test land are measured. The nitrogen consumption trend of the test land is analyzed based on the nitrate nitrogen content. A denitrifying bacteria response coefficient is generated based on the nitrous oxide concentration. The rhizosphere nitrogen loss level of the test land is determined according to the denitrifying bacteria response coefficient. When the rhizosphere nitrogen loss level is high, the test land is drained. The glucose content in the rhizosphere of the test land is collected to determine whether denitrifying bacteria inhibitors should be applied. This achieves dynamic quantitative analysis of the rhizosphere denitrification process and accurately identifies high-risk nitrogen loss states.

[0046] Example 1, such as Figures 1 to 2 As shown, an analytical method for the effects of soil microorganisms on crop rhizosphere includes the following steps:

[0047] Step S1: Monitor the soil moisture content of the land to be tested, assess whether the land to be tested is in a water saturation state based on the soil moisture content, count the duration of saturation of the land to be tested in a water saturation state, and collect the redox potential of the land to be tested.

[0048] Step S2: Calculate the potential decrease rate based on the redox potential, and classify the rhizosphere state of the test land according to the duration of saturation. When the rhizosphere state of the crop is hypoxic, detect the nitrous oxide concentration and nitrate nitrogen content of the test land.

[0049] Step S3: Analyze the nitrogen consumption trend of the land to be tested based on the nitrate nitrogen content, generate the denitrifying bacteria response coefficient of the land to be tested by combining the nitrous oxide concentration, and determine the rhizosphere nitrogen loss level of the land to be tested based on the denitrifying bacteria response coefficient.

[0050] Step S4: When the rhizosphere nitrogen loss level is high, drain the land to be tested. After draining, collect the glucose content in the rhizosphere of the crops in the land to be tested. Determine whether to apply denitrifying bacteria inhibitors to the land to be tested based on the glucose content.

[0051] The specific implementation is as follows:

[0052] In step S1, soil moisture sensors are deployed at a preset sampling depth within the land to be tested to monitor the soil moisture content.

[0053] Soil moisture content is the volume ratio of water contained in a unit volume of soil. Based on the crop type and root distribution characteristics of the land to be tested, the sampling depth range is determined. Soil moisture sensors are vertically buried at the depth position to ensure that the sensing probe of the soil moisture sensor is in close contact with the soil, avoiding gaps or looseness. After the soil moisture sensor is powered on, it measures the change in soil dielectric constant in real time and converts it into the corresponding volumetric moisture content through the built-in calibration curve. The measured volumetric moisture content is taken as the soil moisture content of the land to be tested.

[0054] It should be noted that a soil moisture sensor is an electromagnetic measuring device used to determine the moisture content in soil media. It is a sensing device that calculates and outputs the volumetric water content of soil by sensing changes in soil physical parameters (such as dielectric constant).

[0055] Soil moisture content is used to determine whether the land to be tested is in a water-saturated state. A water-saturated state refers to a state in which the soil pores are completely filled with water and air is expelled. The soil moisture content is then compared with a preset soil saturation threshold.

[0056] When the soil moisture content is greater than or equal to the preset soil saturation threshold, the land to be tested is determined to be in a state of water saturation.

[0057] Otherwise, the land to be tested is determined to be in a state of unsaturated moisture.

[0058] It should be noted that the soil saturation threshold is the maximum water content of soil under saturated conditions, which is obtained through experimental determination. The determination method is to gradually increase the soil water content under laboratory conditions until the seepage stabilizes, and record the limiting water content as the soil saturation threshold.

[0059] When the land to be tested is determined to be in a state of water saturation, the duration of water saturation is statistically analyzed to obtain the saturation duration, which reflects the degree of persistence of the land under the state of oxygen deficiency potential.

[0060] Simultaneously, the redox potential of the land to be tested is collected. The redox potential is an electrochemical index that reflects the intensity of the redox reaction in the soil system of the land to be tested. Specifically, a potential measuring device consisting of a measuring electrode and a reference electrode is inserted into the land to be tested. The potential difference between the measuring electrode and the reference electrode is recorded by a high impedance potentiometer, and the potential difference is used as the redox potential of the land to be tested.

[0061] Redox potential characterizes the availability of electron acceptors and the direction of redox reactions in the soil system. The higher the value, the better the oxidation environment and the more abundant the soil oxygen supply; the lower the value, the stronger the reduction reaction, indicating insufficient soil oxygen supply and a higher possibility of denitrification.

[0062] It should be noted that the potentiometer is an electrochemical measuring instrument used to determine the redox potential in a soil system. It reflects the relative intensity of the redox reaction in the soil solution by detecting the potential difference between the measuring electrode and the reference electrode. The measuring electrode is the signal sensing element in the potentiometer, used to respond to changes in electron activity in the soil system and generate a potential signal. It is made of an inert metal material with stable chemical properties and repeatable electrode potential. The reference electrode is the reference potential element in the potentiometer, possessing the characteristics of stable electrochemical potential, small temperature drift, and good long-term repeatability. It is used to provide a constant reference potential for the measuring electrode. The high-impedance potentiometer is an electronic instrument used to measure weak potential differences and to record the instantaneous potential difference between the measuring electrode and the reference electrode.

[0063] In step S2, the redox potential within the continuous monitoring time series is obtained. Using the redox potential at two adjacent monitoring time points as the basis for calculation, the rate of potential decrease is calculated to reflect the rate of change in soil oxygen supply. The calculation formula is as follows:

[0064] ;

[0065] in, The rate of decrease in potential, and At the monitoring time points respectively and The measured redox potential, and These are the previous monitoring time point and the next monitoring time point, respectively.

[0066] It should be noted that the potential decrease rate characterizes the soil oxygen diffusion rate and the trend of rhizosphere aeration. When the potential decrease rate is negative and the larger the absolute value, it indicates that the oxygen supply is continuously weakening and the soil environment is tending to be in a hypoxic state. When the potential decrease rate is close to zero or positive, it indicates that the oxygen supply is stable or gradually recovering. In this embodiment, the land to be tested is in a state of water saturation, and the potential decrease rate is negative. Its absolute value is used in subsequent calculations.

[0067] The absolute value of the potential decrease rate and the saturation duration are standardized to obtain the potential decrease factor and the duration factor.

[0068] The hypoxia discriminant index of the tested land is obtained by weighted summation of the potential drop factor and the duration factor, which characterizes the rhizosphere aeration status of the tested land. The calculation formula is as follows:

[0069] ;

[0070] in, The hypoxia discrimination index, The potential decrease factor, As a duration factor, α and β are weighting coefficients used to balance the relative influence of the rate of change of potential and the duration of water saturation on the formation of hypoxia.

[0071] The hypoxia discriminant index reflects the overall hypoxia trend of the soil in the tested land. The higher the value, the higher the risk of hypoxia in the rhizosphere.

[0072] The hypoxia discrimination index is compared with the preset hypoxia discrimination threshold:

[0073] When the hypoxia discrimination index is greater than or equal to the preset hypoxia discrimination threshold, the rhizosphere state of the crop in the test land is determined to be hypoxic.

[0074] Conversely, when the hypoxia discrimination index is less than the preset hypoxia discrimination threshold, the rhizosphere state of the crop in the tested land is determined to be oxygenated.

[0075] It should be noted that standardization refers to the process of mapping raw data of different physical quantities or different dimensions to a unified dimension, unified numerical range or unified statistical distribution through specific mathematical transformations. Standardization methods include, but are not limited to, standard linear transformation based on interval scaling, Z-Score standardization based on statistics, or normalization method based on nonlinear mapping functions. The application methods of standardization will not be elaborated here. The weighting coefficients α and β are obtained by multiple linear regression analysis of the contribution of potential drop factor and duration factor to rhizosphere hypoxia in historical monitoring data. The hypoxia discrimination threshold is determined by the percentile method based on the statistical relationship between the hypoxia discrimination index and rhizosphere hypoxia in a large number of soil samples.

[0076] When the rhizosphere of the crop in the test land is determined to be hypoxic, the concentration of nitrous oxide is collected by an infrared gas sensor deployed in the test land. The probe of the infrared gas sensor is inserted into the rhizosphere gas space to ensure that the probe is in full contact with the gas in the test land. The infrared gas sensor obtains the concentration of nitrous oxide in the rhizosphere gas in the test land by emitting a beam of light of a specific wavelength and measuring the absorption intensity of light by nitrous oxide.

[0077] Meanwhile, nitrate nitrogen content is collected by a nitrate nitrogen biosensor deployed in the rhizosphere soil layer of the land to be tested. The nitrate nitrogen biosensor fixes denitrifying bacteria that can specifically reduce nitrate on the transducer surface. When nitrate nitrogen is reduced by these microorganisms or enzymes, it consumes electrons and produces specific metabolites, thereby causing changes in electrical signals. The changes in electrical signals are proportional to the concentration of nitrate nitrogen, thus converting the nitrate nitrogen content into a continuously collected time series value.

[0078] It should be noted that an infrared gas sensor is an electronic measuring device based on the principle of infrared light absorption at a specific wavelength, used to determine the concentration of gas components; a nitrate nitrogen biosensor is an analytical device that combines specific biorecognition elements with physical or chemical transducers, used to specifically detect and quantify the concentration of nitrate ions in environmental samples. Its working principle is to use biorecognition elements to specifically recognize or catalytically convert nitrate ions, and convert this biological reaction into a measurable electrical signal.

[0079] In step S3, after sorting the nitrate nitrogen content data of the land to be tested in chronological order, the nitrate nitrogen content and the corresponding collection time are input into the least squares regression model for fitting, and the fitting intercept and fitting slope are obtained.

[0080] The absolute value of the fitted slope is used as the nitrogen consumption trend of the land under test;

[0081] When the absolute value of the fitting slope is large, it indicates that the nitrate nitrogen content decreases rapidly and the nitrogen consumption trend is fast. When the absolute value of the fitting slope is small, it indicates that the nitrate nitrogen content changes slowly and the nitrogen is in a stable state.

[0082] It should be explained that the least squares regression model is a statistical fitting method based on the principle of minimizing the squared error, used to solve the linear relationship between the independent and dependent variables. In this embodiment, the linear fitting algorithm used to establish the quantitative relationship between time and nitrate nitrogen content calculates the fitting intercept and the fitting slope.

[0083] The nitrogen consumption trend reflects the rate of decrease in nitrate nitrogen content in the tested soil over time. The larger the nitrogen consumption trend, the more significant the decrease in nitrate nitrogen content, the more active the denitrification or nitrogen absorption process in the rhizosphere, and the higher the nitrogen loss. The smaller the nitrogen consumption trend, the slower the change in nitrate nitrogen content, the more stable the rhizosphere nitrogen, and the lower the nitrogen loss.

[0084] After standardizing the nitrogen consumption trend and nitrous oxide concentration respectively, the nitrogen consumption trend coefficient and nitrous oxide coefficient were obtained.

[0085] The product of the nitrogen consumption trend coefficient, the nitrous oxide coefficient, and the preset adjustment factor is used as the denitrifying bacteria response coefficient.

[0086] The larger the response coefficient of denitrifying bacteria, the stronger the activity of denitrifying bacteria and the higher the level of nitrogen loss in the rhizosphere; the smaller the response coefficient of denitrifying bacteria, the weaker the activity of denitrifying bacteria, the inhibited denitrification and the lower the nitrogen loss.

[0087] A higher nitrous oxide concentration indicates a more active denitrification reaction and a higher risk of nitrogen loss in gaseous form; a lower nitrous oxide concentration indicates a weaker denitrification process and a lower degree of nitrogen loss.

[0088] The rhizosphere nitrogen loss level of the land to be tested is determined by comparing the preset denitrifying bacteria coefficient threshold with the denitrifying bacteria response coefficient.

[0089] If the response coefficient of denitrifying bacteria is greater than the preset denitrifying bacteria coefficient threshold, the rhizosphere nitrogen loss level of the tested land is judged to be high.

[0090] Conversely, if the rhizosphere nitrogen loss level of the tested land is determined to be low.

[0091] It should be explained that the preset adjustment factor is used to eliminate the influence of differences in soil type and crop root secretion on the calculation results of denitrifying bacteria response coefficient. It can be set according to soil texture and moisture content. For example, under high temperature and high humidity conditions, the denitrification process is naturally enhanced, and the preset adjustment factor can be selected with a smaller value. The preset denitrifying bacteria coefficient threshold is used to determine the rhizosphere nitrogen loss level of the land to be tested. It can be set according to historical monitoring data. For example, the average value of the denitrifying bacteria response coefficient within the historical monitoring period can be used as the preset denitrifying bacteria coefficient threshold.

[0092] In step S4, when the rhizosphere nitrogen loss level is high, the land to be tested is drained. Drainage treatment refers to removing the accumulated water in the soil to be tested through drainage channels.

[0093] After drainage treatment, the sampling period is preset and divided into multiple sampling times. The glucose concentration signal in the rhizosphere of crops in the land to be tested is collected by glucose oxidase immobilized electrodes deployed in the land to be tested. The glucose concentration signal is converted into glucose content by the signal processing module of the glucose oxidase immobilized electrode.

[0094] Glucose content reflects the supply level of degradable carbon sources in the crop rhizosphere and the sufficiency of energy available to microorganisms. The higher the glucose content, the more degradable carbon sources in the crop rhizosphere, the more vigorous the microbial metabolic activity, the active stage of the denitrification process, and the greater the nitrogen loss. The lower the glucose content, the less degradable carbon sources in the crop rhizosphere, the weaker the microbial activity, the limited denitrification process, and the lower the nitrogen loss.

[0095] The glucose content at each sampling time is sorted in chronological order. If the glucose content at the current sampling time is higher than that at the previous and next sampling times, the current sampling time is recorded as a local peak point; otherwise, the current sampling time is not recorded.

[0096] The average peak content is obtained by taking the average of the glucose contents corresponding to each local peak point.

[0097] Within a preset sampling period, the number of local peak points is counted as the number of glucose peaks, and the product of the average peak content and the number of glucose peaks is used as the glucose pulse index.

[0098] The glucose pulse index reflects the combined frequency and intensity of the release of biodegradable carbon sources from the rhizosphere of crops in the tested soil. The larger the glucose pulse index, the more frequent and higher the peak glucose content in the rhizosphere of crops; the smaller the glucose pulse index, the more gradual the fluctuation of glucose content and the lower the activity of denitrifying bacteria.

[0099] A preset glucose pulse threshold is compared with the glucose pulse index to determine whether to apply a denitrifying bacteria inhibitor to the land to be tested.

[0100] If the glucose pulse index is greater than the preset glucose pulse threshold, it is determined that a denitrifying bacteria inhibitor has been applied to the land to be tested.

[0101] Conversely, no denitrifying bacteria inhibitors are applied to the land to be tested.

[0102] It should be explained that the preset sampling period is a fixed time length for collecting glucose content data, which can be set according to crop type, growth stage, and monitoring accuracy requirements; the glucose oxidase immobilized electrode is an enzyme biosensor deployed in the soil solution environment of the crop rhizosphere to detect changes in the content of soluble glucose in the soil solution in real time; the preset glucose pulse threshold is a reference critical value used to determine the intensity of carbon source release in the crop rhizosphere, which can be set according to crop type, soil texture, and historical data. For example, the glucose pulse index distribution under the same soil conditions and normal nitrogen cycle can be obtained, and the mean of the glucose pulse index can be selected as the preset glucose pulse threshold.

[0103] Finally, it should be noted that in this paper, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0104] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0105] In this document, the singular forms “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that terms such as “comprising / including” or “having” specify the presence of the stated features, integrals, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, integrals, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0106] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.

[0107] The above description of the disclosed embodiments will enable those skilled in the art to make or use various modifications to these embodiments. It will be readily apparent to those skilled in the art that the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for analyzing the effects of soil microorganisms on crop rhizosphere, characterized in that: Includes the following steps: Step S1: Monitor the soil moisture content of the land to be tested, assess whether the land to be tested is in a water saturation state based on the soil moisture content, count the duration of saturation of the land to be tested in a water saturation state, and collect the redox potential of the land to be tested. Step S2: Calculate the potential decrease rate based on the redox potential, and classify the rhizosphere state of the test land according to the duration of saturation. When the rhizosphere state of the crop is hypoxic, detect the nitrous oxide concentration and nitrate nitrogen content of the test land. Step S3: Analyze the nitrogen consumption trend of the land to be tested based on the nitrate nitrogen content, generate the denitrifying bacteria response coefficient of the land to be tested by combining the nitrous oxide concentration, and determine the rhizosphere nitrogen loss level of the land to be tested based on the denitrifying bacteria response coefficient. Step S4: When the rhizosphere nitrogen loss level is high, drain the land to be tested. After draining, collect the glucose content in the rhizosphere of the crops in the land to be tested. Determine whether to apply denitrifying bacteria inhibitors to the land to be tested based on the glucose content.

2. The method for analyzing the effects of soil microorganisms on crop rhizosphere according to claim 1, characterized in that: In step S1, soil moisture sensors are deployed at a preset sampling depth within the land to be tested to monitor the soil moisture content. Soil moisture content is the volume ratio of water contained in a unit volume of soil. Soil moisture content is used to determine whether the land to be tested is in a water-saturated state. A water-saturated state refers to a state in which the soil pores are filled with water and air is expelled. When the soil moisture content is greater than or equal to the preset soil saturation threshold, the land to be tested is determined to be in a state of water saturation. Otherwise, the land to be tested is determined to be in a state of unsaturated moisture.

3. The method for analyzing the effects of soil microorganisms on crop rhizosphere according to claim 1, characterized in that: In step S1, when it is determined that the land to be tested is in a state of water saturation, the duration of water saturation is statistically analyzed to obtain the saturation duration. The potential difference between the measuring electrode and the reference electrode of the potential measuring device is recorded by a high impedance potentiometer, and the potential difference is used as the redox potential of the soil to be tested.

4. The method for analyzing the effects of soil microorganisms on crop rhizosphere according to claim 1, characterized in that: In step S2, the redox potential within the continuous monitoring time series is obtained, and the potential decrease rate is calculated based on the redox potential of two adjacent monitoring time points; The absolute value of the potential decrease rate and the saturation duration are standardized to obtain the potential decrease factor and the duration factor. The hypoxia discrimination index of the land under test is obtained by weighted summation of the potential drop factor and the duration factor.

5. The method for analyzing the effects of soil microorganisms on crop rhizosphere according to claim 1, characterized in that: In step S2, when the hypoxia discrimination index is greater than or equal to the preset hypoxia discrimination threshold, the rhizosphere state of the crop in the test land is determined to be hypoxic. Conversely, when the hypoxia discrimination index is less than the preset hypoxia discrimination threshold, the rhizosphere state of the crop in the test land is determined to be oxygenated. When the rhizosphere of the crop in the test land is determined to be hypoxic, the concentration of nitrous oxide is collected by an infrared gas sensor deployed in the test land. Nitrate nitrogen content is collected by a nitrate nitrogen biosensor deployed in the rhizosphere soil layer of the land to be tested. The nitrate nitrogen content is a continuously collected time series value, forming nitrate nitrogen content data.

6. The method for analyzing the effects of soil microorganisms on crop rhizosphere according to claim 5, characterized in that: In step S3, after sorting the nitrate nitrogen content data of the land to be tested in chronological order, the nitrate nitrogen content and the corresponding collection time are input into the least squares regression model for fitting, and the fitting intercept and fitting slope are obtained. The absolute value of the fitted slope is used as the nitrogen consumption trend of the land under test.

7. The method for analyzing the effects of soil microorganisms on crop rhizosphere according to claim 6, characterized in that: In step S3, the nitrogen consumption trend and nitrous oxide concentration are standardized to obtain the nitrogen consumption trend coefficient and nitrous oxide coefficient, respectively. The product of the nitrogen consumption trend coefficient, the nitrous oxide coefficient, and the preset adjustment factor is used as the denitrifying bacteria response coefficient. If the response coefficient of denitrifying bacteria is greater than the preset denitrifying bacteria coefficient threshold, the rhizosphere nitrogen loss level of the tested land is judged to be high. Conversely, if the rhizosphere nitrogen loss level of the tested land is determined to be low.

8. The method for analyzing the effects of soil microorganisms on crop rhizosphere according to claim 1, characterized in that: In step S4, when the rhizosphere nitrogen loss level is high, the land to be tested is drained. After drainage treatment, the sampling period was preset and divided into multiple sampling times. The glucose content of the crop rhizosphere in the soil to be tested was collected by glucose oxidase immobilized electrode. The glucose content at each sampling time is sorted in chronological order. If the glucose content at the current sampling time is higher than the glucose content at the previous and next sampling times, then the current sampling time is recorded as a local peak point. Conversely, the current sampling time is not recorded.

9. The method for analyzing the effects of soil microorganisms on crop rhizosphere according to claim 8, characterized in that: In step S4, the average value of the glucose content corresponding to each local peak point is taken to obtain the peak average content; Within a preset sampling period, the number of local peak points is counted as the number of glucose peaks, and the product of the average peak content and the number of glucose peaks is used as the glucose pulse index. If the glucose pulse index is greater than the preset glucose pulse threshold, it is determined that a denitrifying bacteria inhibitor has been applied to the land to be tested. Conversely, no denitrifying bacteria inhibitors are applied to the land to be tested.

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