Application method and system of bacterial fertilizer for promoting phosphorus absorption of medicago sativa

Abstract

The invention discloses a bacterial fertilizer application method and system for promoting phosphorus absorption of medicago sativa L. The method comprises the steps that the bacterial fertilizer application amount of each medicago sativa L. area is determined based on the plant phosphorus content, the soil total phosphorus content and the soil available phosphorus content; the method comprises the following steps: starting sensor equipment which is installed in an alfalfa field in advance, acquiring growth environment information of alfalfa, and calculating daily irrigation amount of the alfalfa field by utilizing the growth environment information; a fertilizer solution of a drip irrigation fertilization system is prepared based on the application amount of the bacterial fertilizer and the daily irrigation amount, and the fertilizer solution is used for irrigating and fertilizing the alfalfa field so as to complete the application of the bacterial fertilizer for promoting phosphorus absorption of the alfalfa. By means of the scheme, dissolution and release of phosphorus in soil can be promoted, and then the phosphorus absorption efficiency of alfalfa is promoted.

Description

Technical Field

[0001] The present application relates to the field of agriculture, and in particular to a method and system for applying bacterial fertilizer for promoting phosphorus absorption by alfalfa. Background Art

[0002] In recent years, global agriculture has faced the challenge of soil nutrient management, especially the effective utilization of phosphorus (P). Alfalfa (Medicago sativa L.) is an important forage crop, and its growth and productivity are directly related to the development of animal husbandry. However, the absorption efficiency of phosphorus by alfalfa is relatively low, which seriously restricts its yield and quality. Therefore, how to promote the absorption of phosphorus by alfalfa has become an important research topic. Promoting the absorption of phosphorus by alfalfa not only helps to increase its growth rate and nutritional value, but also reduces the application of chemical fertilizers, reduces agricultural costs, and alleviates environmental pollution. In existing technologies, the utilization rate of phosphorus is mainly improved by applying chemical phosphorus fertilizers and improving fertilization methods. However, these methods have some limitations, such as the limited effectiveness of chemical phosphorus fertilizers in soil, and long-term use can lead to soil acidification, structural deterioration, and environmental pollution. In addition, phosphorus fertilizers have poor mobility in soil and are easily fixed by soil particles, resulting in ineffective absorption by plants. These problems seriously affect the absorption efficiency of phosphorus by alfalfa and the sustainable development of agriculture.

[0003] In response to these problems, researchers have proposed a variety of solutions. For example, improved fertilization techniques, such as staged fertilization and drip fertigation, are applied to improve phosphorus utilization efficiency. However, these methods have limited effectiveness in improving phosphorus utilization and are costly. In addition, soil conditioners, such as organic fertilizers and lime, are used to improve soil structure and chemical properties, thereby increasing phosphorus availability. But these measures usually take a long time to be effective and are difficult to implement in large-scale agricultural production.

[0004] Therefore, there is an urgent need for a technical solution that can promote the dissolution and release of phosphorus in the soil, thereby promoting the phosphorus absorption efficiency of alfalfa. Summary of the invention

[0005] In order to solve the deficiencies of the prior art, the embodiment of the present application provides a method and system for applying bacterial fertilizer to promote phosphorus absorption by alfalfa. The present application solves the technical problems of low phosphorus absorption efficiency in the prior art.

[0006] The present application provides a method for applying bacterial fertilizer to promote phosphorus absorption by alfalfa, comprising: receiving an irrigation and fertilization instruction to promote phosphorus absorption by alfalfa, and performing grid division on an alfalfa field according to the irrigation and fertilization instruction to obtain a plurality of alfalfa areas; performing alfalfa plant sampling in the alfalfa areas in turn, and measuring the phosphorus content of the plants in the alfalfa areas; performing alfalfa soil sampling in the alfalfa areas in turn, and measuring the total phosphorus content and the effective phosphorus content of the soil in the alfalfa areas; amount; based on the phosphorus content of the plants, the total phosphorus content of the soil and the available phosphorus content of the soil, determining the amount of bacterial fertilizer applied in each of the alfalfa areas; starting the sensor equipment pre-installed in the alfalfa field to obtain the growth environment information of the alfalfa, and using the growth environment information to calculate the daily irrigation amount of the alfalfa field; based on the bacterial fertilizer application amount and the daily irrigation amount, preparing the fertilizer solution of the drip irrigation fertigation system, the fertilizer solution is used to perform irrigation fertilization on the alfalfa field to complete the application of bacterial fertilizer that promotes phosphorus absorption by alfalfa.

[0007] In a possible implementation, the method of determining the amount of microbial fertilizer to be applied in each alfalfa area based on the plant phosphorus content, the soil total phosphorus content and the soil effective phosphorus content includes: constructing a phosphorus utilization efficiency model to calculate the phosphorus utilization efficiency using the plant phosphorus content, the soil total phosphorus content and the soil effective phosphorus content; constructing a constraint relationship between phosphorus utilization efficiency and microbial fertilizer application amount; constructing a microbial fertilizer application amount optimization model based on the phosphorus utilization efficiency model and the constraint relationship, and setting an objective function that maximizes the sum of the phosphorus utilization efficiencies of all areas to obtain a target microbial fertilizer application amount optimization problem; and using a target numerical optimization algorithm to solve the target microbial fertilizer application amount optimization problem to obtain the optimal microbial fertilizer application amount.

[0008] In a possible implementation, the sensor equipment pre-installed in the alfalfa field is started to obtain the growth environment information of the alfalfa, and the daily irrigation amount of the alfalfa field is calculated using the growth environment information, including: obtaining the target meteorological data of the day from the sensor to calculate the water vapor parameter group of each field; substituting the water vapor parameter group into the Penman-Monteith equation to calculate the reference crop evapotranspiration of each field; and calculating the daily irrigation amount of each field based on the reference crop evapotranspiration and the alfalfa crop coefficient.

[0009] In a possible implementation, the fertilizer solution of the drip irrigation fertigation system is prepared based on the bacterial fertilizer application amount and the daily irrigation amount, and the fertilizer solution is used to perform irrigation fertilization on alfalfa fields to complete the application of bacterial fertilizer to promote phosphorus absorption by alfalfa, including: dissolving the bacterial fertilizer and compound fertilizer in batches to prepare a low-concentration mother solution, and the mother solution is used to prepare the required fertilizer solution; determining the target volume of the mother solution according to the bacterial fertilizer application amount and the daily irrigation amount, and adding the target volume of the mother solution to the water of the daily irrigation amount to obtain a fertilizer solution; dividing the fertilizer solution into equal parts of a preset application cycle, so as to apply a portion of fertilizer solution in each cycle.

[0010] In a possible implementation, the constructing of a phosphorus utilization efficiency model to calculate phosphorus utilization efficiency using plant phosphorus content, soil total phosphorus content, and soil available phosphorus content includes: in, represents the phosphorus utilization efficiency of the ith region, represents the soil available phosphorus content in the ith region, represents the total phosphorus content of the soil in the ith area, represents the phosphorus content of plants in the i-th area, θ1 represents the first efficiency parameter, whose value is 5, θ2 represents the second efficiency parameter, whose value is 2, and θ3 represents the third efficiency parameter, whose value is 3.

[0011] In a possible implementation, the step of constructing a constraint relationship between phosphorus utilization efficiency and bacterial fertilizer application amount includes: in, represents the soil available phosphorus content in the ith region, μ i represents the amount of fertilizer applied in the ith area, β1 represents the first constraint parameter, which is 50, and β2 represents the second constraint parameter, which is 0.1.

[0012] In a possible implementation, based on the phosphorus utilization efficiency model and the constraint relationship, a microbial fertilizer application amount optimization model is constructed, and an objective function of maximizing the sum of phosphorus utilization efficiencies in all regions is set to obtain a target microbial fertilizer application amount optimization problem, including:

[0013] Where N represents the number of soil regions.

[0014] The present application also provides a bacterial fertilizer application system for promoting phosphorus absorption by alfalfa, comprising: a sampling unit, an optimization unit and a configuration unit; wherein the sampling unit is used to receive an irrigation and fertilization instruction for promoting phosphorus absorption by alfalfa, and to perform grid division on an alfalfa field according to the irrigation and fertilization instruction to obtain a plurality of alfalfa areas; to perform alfalfa plant sampling on the alfalfa areas in turn, and to measure the phosphorus content of the plants in the alfalfa areas; to perform alfalfa soil sampling on the alfalfa areas in turn, and to measure the total phosphorus content and the phosphorus content of the soil in the alfalfa areas; The optimization unit is used to determine the amount of bacterial fertilizer applied in each alfalfa area based on the plant phosphorus content, the total phosphorus content in the soil and the effective phosphorus content in the soil; the configuration unit is used to start the sensor equipment pre-installed in the alfalfa field, obtain the growth environment information of the alfalfa, and calculate the daily irrigation amount of the alfalfa field using the growth environment information; based on the bacterial fertilizer application amount and the daily irrigation amount, a fertilizer solution of the drip irrigation system is prepared, and the fertilizer solution is used to perform irrigation and fertilization on the alfalfa field to complete the application of bacterial fertilizer to promote phosphorus absorption by alfalfa.

[0015] In the bacterial fertilizer application method and system for promoting phosphorus absorption by alfalfa as provided above, the embodiment of the present application promotes the dissolution and release of phosphorus in the soil through the secretion of organic acids and enzymes by the microorganisms in the bacterial fertilizer, and also forms a symbiotic relationship with the plant roots, thereby improving the plant's phosphorus absorption efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 A schematic flow chart of a method for applying a bacterial fertilizer to promote phosphorus absorption by alfalfa provided in an embodiment of the present application;

[0018] Figure 2 A schematic block diagram of a bacterial fertilizer application system for promoting phosphorus absorption by alfalfa provided in an embodiment of the present application. DETAILED DESCRIPTION

[0019] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0020] Those skilled in the art will appreciate that the terms "first", "second" and the like in the embodiments of the present application are only used to distinguish different steps, devices or modules, etc., and do not represent any specific technical meaning, nor do they represent the necessary logical order between them. It should also be understood that in the embodiments of the present application, "multiple" may refer to two or more, and "at least one" may refer to one, two or more. It should also be understood that for any component, data or structure mentioned in the embodiments of the present application, in the absence of explicit limitation or contrary revelation given in the context, it can generally be understood as one or more. In addition, the term "and / or" in the present application is only a kind of association relationship describing the associated objects, indicating that there can be three kinds of relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present application generally indicates that the associated objects before and after are an "or" relationship. It should also be understood that the description of each embodiment in the present application emphasizes the differences between the embodiments, and the same or similar parts can refer to each other. For the sake of brevity, they will not be repeated one by one.

[0021] At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present application and its application or use. The techniques, methods and devices known to ordinary technicians in the relevant fields may not be discussed in detail, but where appropriate, the techniques, methods and devices should be considered as part of the specification. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0022] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0023] Figure 1 The present invention provides a schematic flow chart of a method for applying a bacterial fertilizer to promote phosphorus absorption by alfalfa. Figure 1As shown, at step S101, a fertigation instruction for promoting phosphorus absorption of alfalfa is received, and grid division is performed on the alfalfa field according to the fertigation instruction to obtain multiple alfalfa areas. It should be understood that the instruction can be issued by a remote control center, or it can be set by a field staff according to actual conditions. The instruction can include basic information such as the specific location and area of ​​the alfalfa field. Then, according to the fertigation instruction, grid division is performed on the alfalfa field to obtain multiple alfalfa areas. The purpose of grid division is to more accurately measure and control the fertigation situation of each area. Grid division can adopt automatic partitioning technology based on GPS, or it can be manually measured and marked by staff.

[0024] In step S102, the alfalfa area is sampled in turn to obtain the phosphorus content of the plants in the alfalfa area. Specifically, in one embodiment, 3-5 alfalfa plants with uniform growth are selected in the alfalfa area, and the above-ground part of the alfalfa is cut 2 cm above the soil surface where the alfalfa is located; the above-ground part is placed in a drying box, wherein the drying box intelligently displays the quality data of the material in the box, and sets the drying temperature to 105°C and the drying time to 30 minutes.

[0025] After the drying operation is completed, the drying temperature of the drying box is set to 60°C-75°C again, and the drying operation is continued until the quality data of the material in the box is stable and no longer changes; the dried above-ground part is taken out of the drying box, and the dried above-ground part is weighed with an electronic balance to obtain the dry matter mass; the dried above-ground part is crushed to obtain dry matter crumbs, and the dry matter crumbs are prepared by a h2SO4-H2O2 digestion method to generate a sample test liquid; the sample test liquid is measured by a UV-visible spectrophotometer, and the plant phosphorus concentration of the sample test liquid is obtained by analysis; the plant phosphorus content of the sample test liquid is calculated according to the dry matter mass and the plant phosphorus concentration, and the plant phosphorus content determination of the alfalfa area is completed.

[0026] In step S103, the soil of the alfalfa area is sampled in turn, and the total phosphorus content and the effective phosphorus content of the soil in the alfalfa area are measured. Specifically, in one implementation scenario, in the alfalfa area, soil is collected from three locations at depths of 5 cm, 10 cm, and 15 cm below the soil surface where the alfalfa is located, and a sample of soil is obtained after uniform mixing; the sampled soil is placed in a drying box, wherein the drying box intelligently displays the quality data of the material in the box, and sets the drying temperature to 10°C to 30°C, and the drying time is set to 60 minutes.

[0027] After the drying operation is completed, the dried sampled soil is sequentially rolled, crushed and sieved to obtain a fine-grained soil sample, wherein the sieve hole size of the sieving treatment is 2.00 mm; two portions of fine-grained soil samples, each weighing 2.00 g to 5.00 g, are weighed, and the total phosphorus content of one of the fine-grained soil samples is determined by the H2SO4-HCIO digestion method, and the effective phosphorus content of the soil of the other fine-grained soil sample is determined by the antimony-molybdenum anticolorimetric method, thereby completing the determination of the total phosphorus content and the effective phosphorus content of the soil in the alfalfa area.

[0028] In step S104, the amount of microbial fertilizer applied to each alfalfa region is determined based on the plant phosphorus content, the soil total phosphorus content, and the soil available phosphorus content. Specifically, a phosphorus utilization efficiency model is first constructed to calculate the phosphorus utilization efficiency using the plant phosphorus content, the soil total phosphorus content, and the soil available phosphorus content. It is a key indicator for evaluating the level of regional phosphorus absorption and utilization. Total phosphorus content in soil and soil available phosphorus content There is the following nonlinear relationship:

[0029]

[0030] in, represents the phosphorus utilization efficiency of the ith region, represents the soil available phosphorus content in the ith region, represents the total phosphorus content of the soil in the ith area, represents the plant phosphorus content in the i-th region, θ1 represents the first efficiency parameter, with a value of 5, θ2 represents the second efficiency parameter, with a value of 2, and θ3 represents the third efficiency parameter, with a value of 3. It should be noted that the parameters θ1, θ2, and θ3 can also be model parameters to be trained, and in the form of Sigmoid function, the effects of plant phosphorus content, soil total phosphorus content, and soil available phosphorus content on phosphorus utilization efficiency can be better captured.

[0031] Furthermore, the phosphorus content of the plants Reflects the actual absorption capacity of plants for phosphorus in the area; soil total phosphorus content and available phosphorus content It reflects the soil's ability to supply phosphorus. By analyzing the relationship between these three indicators, the utilization efficiency of phosphorus can be evaluated. The model parameters θ1, θ2, and θ3 can be determined by training historical data through machine learning algorithms (such as gradient descent method).

[0032] Then, the constraint relationship between phosphorus utilization efficiency and the amount of bacterial fertilizer applied is constructed. Applying an appropriate amount of bacterial fertilizer can promote the conversion of insoluble phosphorus in the soil into effective phosphorus, thereby improving the absorption and utilization of phosphorus by plants. The applicant found through experiments that the amount of bacterial fertilizer applied μ i Available phosphorus content in soil There is the following logarithmic relationship:

[0033]

[0034] in, represents the soil available phosphorus content in the ith region, μ i represents the amount of bacterial fertilizer applied in the ith region, β1 represents the first constraint parameter, which is 50, and β2 represents the second constraint parameter, which is 0.1. This also shows that with the increase in the amount of bacterial fertilizer applied, the available phosphorus content in the soil will gradually tend to saturation.

[0035] Next, based on the phosphorus utilization efficiency model and the constraint relationship, a fertilizer application optimization model is constructed, and an objective function that maximizes the sum of phosphorus utilization efficiencies in all regions is set to obtain a target fertilizer application optimization problem. Specifically, the optimization problem can be described as:

[0036]

[0037] Where N represents the number of soil regions. Specifically, the objective function is to maximize the sum of the phosphorus utilization efficiencies of all regions. The constraints are: the phosphorus utilization efficiency of each region satisfies the pre-trained model; the soil available phosphorus content in each region satisfies a known logarithmic relationship with the amount of microbial fertilizer applied; and the amount of microbial fertilizer applied must be non-negative.

[0038] Because the optimization problem belongs to a nonlinear programming problem, the target fertilizer application amount optimization problem is solved using a target numerical optimization algorithm to obtain the optimal fertilizer application amount. In one embodiment, the problem can be solved by a numerical optimization algorithm (such as an interior point method, a sequential quadratic programming method, etc.). In the solution process, the known plant phosphorus content, soil total phosphorus content, and model parameters θ1, θ2, θ3, β1, and β2 in each region need to be used as input.

[0039] In order to explain this method more intuitively, we take a certain alfalfa planting area as an example for analysis. The area is divided into 5 areas, and the relevant data of each area are as follows:

[0040]

[0041] Through a series of experiments and machine learning training, this application obtained the following model parameter values: θ1 = 5, θ2 = 2, θ3 = 3, β1 = 50, β2 = 0.1. Substituting these data and parameters into the optimization model and solving it using the sequential quadratic programming algorithm, the following optimal fertilizer application amount can be obtained:

[0042]

[0043]

[0044] The corresponding soil available phosphorus content is:

[0045]

[0046] Substituting the optimized soil available phosphorus content into the phosphorus utilization efficiency model, the phosphorus utilization efficiency of each region can be calculated:

[0047]

[0048] The total phosphorus utilization efficiency is 3.62, which is 27% higher than 2.85 when no fertilizer is applied. It can be seen that by establishing a mathematical model and optimizing the calculation based on actual data, this application can more accurately determine the optimal fertilizer application amount for each area, thereby maximizing the phosphorus utilization efficiency of the entire planting area. The advantage of this model is that it comprehensively considers the three key factors of plant phosphorus content, soil total phosphorus content and soil effective phosphorus content; the machine learning method is used to train the model parameters, which can better fit the actual situation; the fertilizer application optimization model is modeled as a mathematical programming problem, and the solution process is rigorous; not only can the optimal fertilizer application amount be output, but also the corresponding soil effective phosphorus content and phosphorus utilization efficiency prediction values ​​can be given.

[0049] At step S105, the sensor equipment pre-installed in the alfalfa field is started to obtain the growth environment information of the alfalfa, and the daily irrigation amount of the alfalfa field is calculated using the growth environment information. In order to accurately control the irrigation amount of the alfalfa field and improve the efficiency of water resource utilization, various environmental sensors pre-installed in the field can be used to obtain the key environmental parameters required for crop growth in real time, and the daily irrigation amount can be dynamically calculated and adjusted using a mathematical model.

[0050] Specifically, first, the target meteorological data of the day is obtained from the sensor to calculate the water vapor parameter group of each field. In one embodiment, the following environmental sensors are installed in the alfalfa field: soil moisture sensor, which is used to measure the soil volume moisture content and reflect the soil moisture condition. Air temperature and humidity sensor, which measures air temperature and relative humidity, can be used to calculate auxiliary parameters such as atmospheric saturated vapor pressure. Light sensor, which measures solar radiation intensity and is used to evaluate photosynthesis conditions. Wind speed and direction sensor, which detects wind speed and wind direction and is used to estimate field water evaporation.

[0051] These sensors all use wireless transmission technology to upload detection data to the cloud server in real time. At the same time, several groups of sensors of the same type are installed in each field to ensure comprehensive coverage of the entire planting area. Then, the water vapor parameter group is substituted into the Penman-Monteith equation to calculate the reference crop evapotranspiration of each field.

[0052] In order to calculate the daily irrigation amount based on the sensor data, the following mathematical model is established in the embodiment of the present application: i: field number, with values ​​of 1, 2, ..., N; I i : Solar radiation intensity of the i-th field (W / m 2 );T i : Average temperature of the i-th field ℃; RH i : Average relative humidity of the i-th field %; W i : average wind speed in the ith field m / s; θ i : Average soil volume moisture content in the i-th field %; ET i : Reference crop evapotranspiration of the i-th field mm / day; K c : Alfalfa crop coefficient, used to convert reference crop evapotranspiration into actual crop evapotranspiration; IR i : Daily irrigation amount of the ith field (mm / day).

[0053] Daily irrigation amount IR i Modeled as reference crop evapotranspiration ET i and alfalfa crop coefficient K c The product of IR i =K c ×ET i , where the reference crop evapotranspiration ET i Calculated by FAO Penman-Monteith equation: This equation comprehensively considers the influence of multiple environmental factors such as radiation, temperature, humidity and wind speed on evapotranspiration. Among them: Δ is the slope of the saturated water vapor pressure curve in kPa / ℃; R n is the net radiation on the crop surface MJ / m 2 / day; G is the soil heat flux density MJ / m 2 / day; γ is a constant 0.067 kPa / ℃; T i is the average temperature of the ith field in °C; U2 is the wind speed at a height of 2 m in m / s; e s is the saturated water vapor pressure kPa; e a is the actual water vapor pressure in kPa.

[0054] The above parameters can be calculated by a series of auxiliary equations using sensor measurement data. For example:

[0055]

[0056] R n =R ns -R nl ,

[0057] Where R ns and R nl They are short-wave radiation and long-wave radiation, which can be determined by the solar radiation intensity I i and other environmental parameters were estimated.

[0058] As for the crop coefficient K c , it is necessary to establish an empirical formula or find a ready-made reference value table based on a large amount of field test data, combined with factors such as crop growth stage and vegetation coverage. Generally speaking, for medium-sized crops such as alfalfa, its K c The value is about 0.4 in the early growth stage, about 1.0 in the middle stage, and about 0.6 in the late stage.

[0059] Secondly, based on the reference crop evapotranspiration and the alfalfa crop coefficient, the daily irrigation amount of each field is calculated. In general, the specific steps for calculating the daily irrigation amount are as follows: obtain the solar radiation intensity I of the day from each sensor i , average temperature T i , average relative humidity RH i , average wind speed Wi and average soil volume moisture content θ i Using the auxiliary equation above, the saturated water vapor pressure e of each field is calculated. s , actual water vapor pressure e a , the slope of the saturated water vapor pressure curve Δ, the net radiation R n and other intermediate parameters; Substitute these intermediate parameters into the Penman-Monteith equation to calculate the reference crop evapotranspiration for each field; According to the crop growth stage, check or estimate the current alfalfa crop coefficient; ET i and K c Substitute into the formula IR i =K c ×ET i, we can get the daily irrigation amount IR of the i-th field i .

[0060] In order to explain the whole calculation process more specifically, a specific field is used as an example. Assume that the measured environmental parameters of the field on that day are:

[0061] Solar radiation intensity I = 650W / m 2 ; Average temperature T = 28℃; Average relative humidity RH = 65%; Average wind speed W = 1.8m / s; Average soil volume moisture content θ = 25%; At the same time, alfalfa is currently in the middle growth stage, and the crop coefficient K c =1.0. First, calculate the auxiliary parameters based on the measured values:

[0062]

[0063] Assume R ns =20MJ / m 2 / day,R nl =5MJ / m 2 / day, G=0, then: R n =R ns -R nl =20-5=15MJ / m 2 / day.

[0064] Substitute the above intermediate parameters into the Penman-Monteith equation:

[0065]

[0066] Finally, substitute the reference crop evapotranspiration and crop coefficient into the formula: IR = K c ×ET=1.0×5.83=5.83mm / day.

[0067] Therefore, under the above environmental conditions, the daily irrigation amount of alfalfa in this field should be controlled at around 5.83 mm / day.

[0068] At step S106, a fertilizer solution of the drip irrigation fertigation system is prepared based on the amount of bacterial fertilizer applied and the daily irrigation amount, and the fertilizer solution is used to perform fertigation on the alfalfa field to complete the application of bacterial fertilizer to promote phosphorus absorption by alfalfa. In order to promote the absorption and utilization of phosphorus by alfalfa, bacterial fertilizer containing phosphorus-dissolving bacteria can be applied, and the fertilizer solution after the bacterial fertilizer is mixed with chemical fertilizers can be evenly transported to the field through the drip irrigation system to achieve accurate and efficient irrigation and fertilization operations.

[0069] Specifically, first, the bacterial fertilizer and the compound fertilizer are dissolved in batches to prepare a low-concentration mother solution, and the mother solution is used to prepare the required fertilizer solution; then, the target volume of the mother solution is determined according to the application amount of the bacterial fertilizer and the daily irrigation amount, and the target volume of the mother solution is added to the water of the daily irrigation amount to obtain a fertilizer solution; finally, the fertilizer solution is divided into equal parts according to a preset application cycle, so that one portion of the fertilizer solution is applied in each cycle.

[0070] In an implementation scenario, the amount of fertilizer required per hectare of field must first be determined based on the growth of alfalfa and the phosphorus content in the soil. Through field investigation and soil testing, the following data was obtained: Phosphorus requirement of alfalfa: 60kg / hm 2 ; Available phosphorus content in soil: 20mg / kg; Number of phosphorus-dissolving bacteria in fertilizer: 10 8 CFU / g; effective phosphorus content in the bacterial fertilizer: 8%. Then the amount of bacterial fertilizer applied per hectare of field M can be calculated according to the following formula: For the convenience of calculation, take M = 7500kg / hm 2 =750kg / hectare.

[0071] According to the model for calculating daily irrigation volume based on environmental sensor data introduced above, assuming that the environmental parameter measurement value of a field on that day is: solar radiation intensity I = 650W / m 2 ; Average temperature T = 28℃; Average relative humidity RH = 65%; Average wind speed W = 1.8m / s; Average soil volume moisture content θ = 25%. At the same time, the alfalfa in the field is currently in the middle and late growth stage, and the crop coefficient K c =0.8. According to the above calculation steps, we can get:

[0072] e s =3.37kPa

[0073] e a =2.36kPa

[0074] Δ=0.221kPa / ℃,

[0075] R n=16MJ / m 2 / day

[0076] Substituting these intermediate parameters into the Penman-Monteith equation, the reference crop evapotranspiration can be calculated: Then multiply the reference crop evapotranspiration by the crop coefficient to get the irrigation amount for the field on that day: IR = K c ×ET=0.8×5.12=4.10mm / day. Converted into volume units, the daily irrigation volume per hectare is: V=IR×10000m2 / hm 2 =4.10×10000=41000L / hm 2 =41m 3 / hm 2 .

[0077] Next, prepare the drip irrigation fertilizer solution. To achieve the combined application of bacterial fertilizer and chemical fertilizer, the bacterial fertilizer can be dissolved in water first, and then an appropriate amount of compound fertilizer can be added. Assume that the compound fertilizer selected is N: P2O5: K2O = 15: 15: 15, and the application amounts of the three elements of nitrogen, phosphorus and potassium are required to be:

[0078] Nitrogen requirement: 180kg / hm 2 ; Phosphorus P2O5 requirement: 90kg / hm 2 ; Potassium K2O requirement: 120kg / hm 2 The application amount of compound fertilizer is:

[0079]

[0080] In order to avoid the impact of excessive fertilizer concentration on crop growth, the bacterial fertilizer and compound fertilizer can be dissolved in batches, first prepared into a low-concentration "mother solution", and then the mother solution is used to prepare the required fertilization solution.

[0081] Assume that 1 / 4 of the bacterial fertilizer and compound fertilizer is dissolved in 10m 3 In water, the concentration of bacterial fertilizer in the "mother solution" is: The concentration of compound fertilizer is:

[0082] Then, prepare the fertilizer solution according to the daily irrigation volume of 41m 3 / hm 2 The volume of mother liquor required for preparing the fertilization solution is calculated based on the total application amount of bacterial fertilizer and compound fertilizer.

[0083] The total amount of bacterial fertilizer is 750kg / hm 2 , then the mother solution is needed: The total amount of compound fertilizer is 2600kg / hm 2 , then the mother solution is needed: Add these two parts of mother liquor to 41m 3 The daily irrigation volume can be used to obtain a fertilization solution containing bacterial fertilizer and compound fertilizer. At the same time, in order to fully mix the bacterial fertilizer and compound fertilizer, a stirring device can be installed in the liquid mixing tank, or two-way infusion pipelines can be used to transport the bacterial fertilizer mother solution and the compound fertilizer mother solution to the mixer respectively for mixing, and then the fertilizer solution can be evenly transported to the field through the drip irrigation system.

[0084] Since the total application amount of bacterial fertilizer and compound fertilizer is large, if all of them are applied at once, the fertilizer concentration will be too high, which will affect the growth of crops. Therefore, the total application amount can be applied in batches, that is, only a part of the fertilizer solution is prepared each time, and it is applied in several cycles.

[0085] In one embodiment, assuming that the total application amount is divided into 5 equal parts, and 1 / 5 of the fertilizer amount is applied in each cycle, the fertilizer amount applied in each cycle is: Fertilizer application amount: Compound fertilizer application amount: According to the above method, the fertilizer solution to be prepared in each cycle contains: Fertilizer mother solution: Compound fertilizer mother solution: This 16m 3 Add the mother liquor to 41m 3 The fertilizer solution for this cycle can be obtained from the daily irrigation volume.

[0086] After 5 cycles of application, the total amount of bacterial fertilizer and compound fertilizer can be applied to the field. There can be a 7-10 day interval between each cycle to give the crops enough time to absorb and utilize the applied nutrients.

[0087] Through the above process, the application amount of bacterial fertilizer and chemical fertilizer can be determined scientifically and reasonably, and according to factors such as daily irrigation volume and crop growth stage, suitable drip irrigation fertilizer solution can be prepared to implement refined irrigation and fertilization operations for alfalfa fields.

[0088] This precise fertilization model based on environmental data can not only effectively promote the absorption and utilization of phosphorus by alfalfa, but also avoid resource waste and environmental pollution caused by excessive fertilization. It has high economic and ecological value.

[0089] Of course, in actual application, the fertilization plan needs to be appropriately adjusted according to the specific situation. At the same time, attention should be paid to regular monitoring of crop growth conditions and soil nutrient changes, and timely feedback adjustments should be made to obtain the best fertilization effect.

[0090] Figure 2 A schematic block diagram of a bacterial fertilizer application system for promoting phosphorus absorption by alfalfa provided in an embodiment of the present application. It should be understood that the system shown in the figure is exemplary and not restrictive. This means that the system architecture involved is not limited to a specific form or design, but is presented as an example. In other words, the architecture shown in the figure can be regarded as a way of expression to clearly describe related concepts and relationships, and does not exclude other forms of architecture. Therefore, when explaining the architecture in the picture, it should be understood that the model has flexibility and diversity, and its purpose is to provide an exemplary description rather than a restrictive provision on a specific form.

[0091] Specifically, the system includes a sampling unit 201, an optimization unit 202 and a configuration unit 203. The sampling unit 201 is used to receive an irrigation and fertilization instruction for promoting phosphorus absorption by alfalfa, and to perform grid division on the alfalfa field according to the irrigation and fertilization instruction to obtain multiple alfalfa areas; to perform alfalfa plant sampling on the alfalfa area in turn, and to measure the plant phosphorus content of the alfalfa area; to perform alfalfa soil sampling on the alfalfa area in turn, and to measure the soil total phosphorus content and soil available phosphorus content of the alfalfa area. The optimization unit 202 is used to determine the amount of bacterial fertilizer to be applied in each alfalfa area based on the plant phosphorus content, the soil total phosphorus content and the soil available phosphorus content. The configuration unit 203 is used to start the sensor equipment pre-installed in the alfalfa field, obtain the growth environment information of the alfalfa, and use the growth environment information to calculate the daily irrigation amount of the alfalfa field; based on the application amount of the bacterial fertilizer and the daily irrigation amount, the fertilizer solution of the drip irrigation system is prepared, and the fertilizer solution is used to perform irrigation and fertilization on the alfalfa field to complete the application of bacterial fertilizer to promote phosphorus absorption by alfalfa.

[0092] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description.

[0093] It should also be noted that, in this article, relational terms such as first and second, etc. are only used 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. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0094] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for applying bacterial fertilizer to promote phosphorus absorption by alfalfa, characterized in that: include: receiving an irrigation and fertilization instruction for promoting phosphorus absorption by alfalfa, and performing grid division on the alfalfa field according to the irrigation and fertilization instruction to obtain a plurality of alfalfa areas; Sampling alfalfa plants in the alfalfa area in sequence to determine the phosphorus content of the plants in the alfalfa area; The alfalfa soil is sampled in turn in the alfalfa area, and the total phosphorus content and the available phosphorus content of the soil in the alfalfa area are measured; Determining the amount of bacterial fertilizer to be applied in each alfalfa area based on the plant phosphorus content, the soil total phosphorus content and the soil available phosphorus content; activating a sensor device installed in advance in an alfalfa field to obtain growth environment information of the alfalfa, and using the growth environment information to calculate a daily irrigation amount for the alfalfa field; A fertilizer solution of a drip fertigation system is prepared based on the amount of bacterial fertilizer applied and the daily irrigation amount. The fertilizer solution is used to perform fertigation on an alfalfa field to complete the application of bacterial fertilizer to promote phosphorus absorption by alfalfa.

2. The method for applying bacterial fertilizer according to claim 1, characterized in that: in, The method of determining the amount of bacterial fertilizer to be applied in each alfalfa region based on the plant phosphorus content, the soil total phosphorus content and the soil available phosphorus content comprises: A phosphorus utilization efficiency model was constructed to calculate phosphorus utilization efficiency using plant phosphorus content, soil total phosphorus content and soil available phosphorus content; Establish the constraint relationship between phosphorus utilization efficiency and the amount of bacterial fertilizer applied; Based on the phosphorus utilization efficiency model and the constraint relationship, a microbial fertilizer application amount optimization model is constructed, and an objective function of maximizing the sum of phosphorus utilization efficiencies in all regions is set to obtain a target microbial fertilizer application amount optimization problem; The target numerical optimization algorithm is used to solve the target fertilizer application amount optimization problem to obtain the optimal fertilizer application amount.

3. The bacterial fertilizer application method according to claim 1, characterized in that: in, The step of starting the sensor device installed in advance on the alfalfa field to obtain the growth environment information of the alfalfa and using the growth environment information to calculate the daily irrigation amount of the alfalfa field includes: Obtain the target meteorological data of the day from the sensor to calculate the water vapor parameter group for each field; Substituting the water vapor parameter set into the Penman-Monteith equation to calculate the reference crop evapotranspiration for each field; Based on the reference crop evapotranspiration and the alfalfa crop coefficient, the daily irrigation amount for each field was calculated.

4. The bacterial fertilizer application method according to claim 1, characterized in that: in, The method comprises preparing a fertilizer solution of a drip fertigation system based on the amount of bacterial fertilizer applied and the amount of daily irrigation, wherein the fertilizer solution is used to perform fertigation on an alfalfa field to complete the application of bacterial fertilizer to promote phosphorus absorption by alfalfa, and comprising: Dissolving the bacterial fertilizer and the compound fertilizer in batches to prepare a low-concentration mother solution, wherein the mother solution is used to prepare a required fertilizer solution; Determining the target volume of the mother solution according to the amount of bacterial fertilizer applied and the daily irrigation amount, and adding the target volume of the mother solution to the water of the daily irrigation amount to obtain a fertilizer solution; Divide the fertilizer solution into equal portions for a preset application period so as to apply one portion of the fertilizer solution in each period.

5. The bacterial fertilizer application method according to claim 2, characterized in that: in, The phosphorus utilization efficiency model is constructed to calculate the phosphorus utilization efficiency using the plant phosphorus content, the soil total phosphorus content and the soil available phosphorus content, including: in, represents the phosphorus utilization efficiency of the ith region, represents the soil available phosphorus content in the ith area, represents the total phosphorus content of the soil in the ith area, represents the phosphorus content of plants in the i-th area, θ1 represents the first efficiency parameter, whose value is 5, θ2 represents the second efficiency parameter, whose value is 2, and θ3 represents the third efficiency parameter, whose value is 3.

6. The bacterial fertilizer application method according to claim 5, characterized in that: in, Construct the constraint relationship between phosphorus utilization efficiency and fertilizer application amount, including: in, represents the soil available phosphorus content in the ith region, μ i represents the amount of fertilizer applied in the ith area, β1 represents the first constraint parameter, which is 50, and β2 represents the second constraint parameter, which is 0.

1.

7. The bacterial fertilizer application method according to claim 6, characterized in that: in, Based on the phosphorus utilization efficiency model and the constraint relationship, a microbial fertilizer application amount optimization model is constructed, and an objective function for maximizing the sum of phosphorus utilization efficiencies in all regions is set to obtain a target microbial fertilizer application amount optimization problem, including: Where N represents the number of soil regions.

8. A bacterial fertilizer application system for promoting phosphorus absorption by alfalfa, characterized in that: include: Sampling unit, optimization unit and configuration unit; wherein, The sampling unit is used to receive an irrigation and fertilization instruction for promoting phosphorus absorption by alfalfa, and to perform grid division on the alfalfa field according to the irrigation and fertilization instruction to obtain a plurality of alfalfa areas; to perform alfalfa plant sampling on the alfalfa areas in turn, and to measure the phosphorus content of the plants in the alfalfa areas; to perform alfalfa soil sampling on the alfalfa areas in turn, and to measure the total phosphorus content and the available phosphorus content of the soil in the alfalfa areas; The optimization unit is used to determine the amount of bacterial fertilizer to be applied in each alfalfa area based on the plant phosphorus content, the soil total phosphorus content and the soil available phosphorus content; The configuration unit is used to start the sensor equipment pre-installed in the alfalfa field, obtain the growth environment information of the alfalfa, and use the growth environment information to calculate the daily irrigation amount of the alfalfa field; based on the application amount of the bacterial fertilizer and the daily irrigation amount, the fertilizer solution of the drip irrigation system is prepared, and the fertilizer solution is used to perform irrigation and fertilization on the alfalfa field to complete the application of bacterial fertilizer to promote phosphorus absorption by alfalfa.

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