Corn field water and fertilizer integrated water and fertilizer utilization efficiency optimization method and system

Abstract

The invention relates to the technical field of water and fertilizer integration, in particular to a water and fertilizer utilization efficiency optimization method and system for water and fertilizer integration in a corn field, which comprises the following steps: judging whether a soil water content prediction curve has a soil lower limit water content, if so, determining an irrigation selection time period according to the soil lower limit water content, and determining simulated irrigation parameters according to the irrigation selection time period; performing soil irrigation simulation by using the soil water content prediction curve to obtain a soil water content simulation curve set, selecting a soil water content target curve in the soil water content simulation curve set, and identifying a target irrigation time point and a target irrigation water amount corresponding to the soil water content target curve; selecting target fertilization time and target fertilization amount from the soil water content target curve, and fertilizing the corn field according to the target irrigation time point, the target irrigation water amount, the target fertilization time and the target fertilization amount. The water and fertilizer efficiency and the regulation and control precision of current water and fertilizer integrated fertilization of the corn field can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated water and fertilizer management, and particularly to a method and system for optimizing the water and fertilizer utilization efficiency of integrated water and fertilizer management in corn fields. Background Art

[0002] There are significant differences in the water and fertilizer requirements of corn at different growth stages. For example, the nitrogen demand surges during the jointing stage, and the potassium demand increases during the filling stage. However, the traditional methods of flood irrigation and broadcasting cannot accurately match the crop requirements, resulting in nutrient leaching in the early stage and fertilizer deficiency in the later stage.

[0003] During the current process of integrated water and fertilizer management in corn fields, it is mainly based on the water and fertilizer requirements of corn. At key nodes such as the sowing stage, jointing stage, tasseling stage, and filling stage, it is supplied in batches and quantitatively. For example, in the summer maize area of the North China Plain and the Huang-Huai Plain, when the soil moisture content at 0-20 cm is lower than 65% after sowing, drip irrigation is started, and 3-5 kg / mu of water-soluble fertilizer with high phosphorus and medium nitrogen is used to ensure the uniformity of seedling emergence. However, this method of batch and quantitative supply does not dynamically predict the soil moisture content in combination with rainfall, resulting in lag and limitations in the selection of drip irrigation time and fertilization time. Therefore, the current integrated water and fertilizer management in corn fields has problems such as low water and fertilizer efficiency and poor regulation accuracy. Summary of the Invention

[0004] The present invention provides a method and system for optimizing the water and fertilizer utilization efficiency of integrated water and fertilizer management in corn fields, and its main purpose is to improve the water and fertilizer efficiency and regulation accuracy of the current integrated water and fertilizer management in corn fields.

[0005] To achieve the above object, a method for optimizing the water and fertilizer utilization efficiency of integrated water and fertilizer management in corn fields provided by the present invention includes: Obtain the optimal soil moisture range corresponding to the current fertilization stage, and identify the lower limit soil moisture content in the optimal soil moisture range; Obtain the current rainfall prediction curve, and perform soil moisture prediction according to the current rainfall prediction curve to obtain a soil moisture prediction curve; Judge whether the lower limit soil moisture content exists in the soil moisture prediction curve; If the lower limit soil moisture content does not exist in the soil moisture prediction curve, return to the step of obtaining the current rainfall prediction curve; If the lower limit soil moisture content exists in the soil moisture prediction curve, determine the irrigation selection period according to the lower limit soil moisture content, where the end point of the irrigation selection period is the time point corresponding to the lower limit soil moisture content; Determine the simulated irrigation parameters according to the irrigation selection period, and perform soil irrigation simulation using the simulated irrigation parameters and the soil moisture prediction curve to obtain a set of soil moisture simulation curves, where the simulated irrigation parameters include: simulated irrigation time points and simulated irrigation water volumes; Select a target soil water content curve from the set of soil water content simulation curves according to a preset soil water content standard, and identify the target irrigation time point and target irrigation water volume corresponding to the target soil water content curve; Select the target fertilization time and target fertilization amount from the target soil water content curve according to a preset fertilization standard; Apply fertilizer to the corn field according to the target irrigation time point, target irrigation water volume, target fertilization time and target fertilization amount, and complete the optimization of the water and fertilizer utilization efficiency of the water and fertilizer integration in the corn field.

[0006] Optionally, the soil water content prediction based on the current rainfall prediction curve to obtain the soil water content prediction curve includes: Obtain the current soil water content, and calculate the current soil water storage according to the current soil water content using the following formula: ; Where, represents the current soil water storage, represents the current soil water content, represents the soil bulk density, represents the soil layer depth; Extract the first predicted rainfall amount from the current rainfall prediction curve, where the first predicted rainfall amount refers to the rainfall amount predicted for the next day in the current rainfall prediction curve; Judge whether the first predicted rainfall amount is 0; If the first predicted rainfall amount is 0, calculate the iterative soil water storage using a pre-constructed first soil water storage formula and a preset crop evapotranspiration amount and reference deep percolation amount, where the first soil water storage formula is as follows: ; Where, represents the iterative soil water storage, represents the crop evapotranspiration amount, represents the reference deep percolation amount, represents the field capacity; If the first predicted rainfall amount is not 0, calculate the first surface runoff amount according to the first predicted rainfall amount using a pre-constructed surface runoff formula; Calculate the first deep percolation amount using a pre-constructed deep percolation amount formula according to a preset unsaturated hydraulic conductivity; Calculate the iterative soil water storage according to the current soil water storage, the first predicted rainfall amount, the first surface runoff amount, the first deep percolation amount and the crop evapotranspiration amount using a pre-constructed second soil water storage formula, where the second soil water storage formula is as follows: ; Among them, represents the first predicted rainfall, represents the first surface runoff, represents the first deep percolation; Using the iterative soil water storage, calculate the iterative soil water content using the following formula: ; Among them, represents the iterative soil water content; Judge whether there is a preset predicted rainfall for the next day for the first predicted rainfall, where the predicted rainfall for the next day refers to the predicted rainfall on the day after the first predicted rainfall; If there is a predicted rainfall for the next day for the first predicted rainfall, identify the predicted rainfall for the next day of the first predicted rainfall; Update the current soil water storage and the first predicted rainfall respectively using the iterative soil water storage and the predicted rainfall for the next day, and return to the above step of judging whether the first predicted rainfall is 0; If there is no predicted rainfall for the next day for the first predicted rainfall, draw a soil water content prediction curve according to the current soil water content and the iterative soil water content.

[0007] Optionally, the surface runoff formula is as follows: ; Among them, represents the number of curves.

[0008] Optionally, the deep percolation formula is as follows: ; Among them, represents the unsaturated hydraulic conductivity, represents the hydraulic gradient.

[0009] Optionally, the determination of the irrigation selection period according to the lower limit soil water content includes: Judge whether there is only one lower limit soil water content in the soil water content prediction curve; If there is only one lower limit soil water content in the soil water content prediction curve, identify the soil water content prediction time point corresponding to the lower limit soil water content; If there is more than one lower limit soil water content in the soil water content prediction curve, identify the first lower limit soil water content in the soil water content prediction curve, where the first lower limit soil water content refers to the first lower limit soil water content in the soil water content prediction curve; Identify the soil water content prediction time point corresponding to the first lower limit soil water content; Obtain the current time point, and determine the irrigation selection period according to the current time point and the soil water content prediction time point.

[0010] Optionally, determine the simulated irrigation parameters according to the irrigation selection period, and perform soil irrigation simulation using the simulated irrigation parameters and the soil water content prediction curve to obtain a set of soil water content simulation curves, including: Select a set of simulated irrigation time points at preset time intervals within the irrigation selection period, and sequentially select simulated irrigation time points from the set of simulated irrigation time points. Identify the simulated irrigation date corresponding to the simulated irrigation time point. Identify the simulated predicted rainfall corresponding to the simulated irrigation date in the current rainfall prediction curve. Obtain a set of simulated irrigation water volumes, sequentially extract the simulated irrigation water volumes from the set of simulated irrigation water volumes, and update the first soil water storage formula and the second soil water storage formula using the simulated irrigation water volumes. Among them, the updated first soil water storage formula is as follows: ; Among them, represents the simulated irrigation water volume; The updated second soil water storage formula is as follows: ; Update the first predicted rainfall using the simulated predicted rainfall, and return to the above step of judging whether the first predicted rainfall is 0 to obtain the soil water content simulation curve corresponding to the simulated irrigation parameters. Collect the soil water content simulation curves corresponding to each simulated irrigation parameter to obtain a set of soil water content simulation curves.

[0011] Optionally, select the soil water content target curve in the set of soil water content simulation curves according to the preset soil water content standard, including: Sequentially extract the soil water content simulation curves from the set of soil water content simulation curves. Determine the intermediate soil water content according to the best soil water content interval, where the intermediate soil water content refers to the median of the best soil water content interval. Construct an intermediate soil water content line segment according to the intermediate soil water content. Judge whether there is an intersection between the soil water content simulation curve and the intermediate soil water content line segment. If there is no intersection between the soil water content simulation curve and the intermediate soil water content line segment, judge whether the soil water content simulation curve is above the intermediate soil water content line segment. If the soil water content simulation curve is above the middle line segment of the soil water content, the recommended degree of the simulation irrigation parameter is calculated using the following formula: ; Wherein, represents the recommended degree of the simulation irrigation parameter, represents the first recommended weight, represents the integral area of the soil water content simulation curve, represents the integral area of the middle line segment of the soil water content; If the soil water content simulation curve is not above the middle line segment of the soil water content, the recommended degree of the simulation irrigation parameter is calculated using the following formula: ; Wherein, represents the second recommended weight; If there is an intersection point between the soil water content simulation curve and the middle line segment of the soil water content, the soil water content simulation curve and the middle line segment of the soil water content are segmented using the intersection point to obtain a first time zone line pair and a second time zone line pair; Calculate the recommended degree of the simulation irrigation parameter according to the first time zone line pair and the second time zone line pair; Collect the recommended degrees of the simulation irrigation parameters corresponding to each soil water content simulation curve to obtain a set of recommended degrees of the simulation irrigation parameters, identify the maximum recommended degree of the simulation irrigation parameter in the set of recommended degrees of the simulation irrigation parameters, and identify the soil water content target curve corresponding to the maximum recommended degree of the simulation irrigation parameter.

[0012] Optionally, the calculating the recommended degree of the simulation irrigation parameter according to the first time zone line pair and the second time zone line pair includes: Identify the first target recommended weight of the first time zone line pair and the second target recommended weight of the second time zone line pair respectively; Calculate the first absolute area difference of the first time zone line pair and the second absolute area difference of the second time zone line pair respectively; Calculate the recommended degree of the first time zone according to the first target recommended weight and the first absolute area difference, and calculate the recommended degree of the second time zone according to the second target recommended weight and the second absolute area difference; Calculate the recommended degree of the simulation irrigation parameter according to the recommended degree of the first time zone and the recommended degree of the second time zone, wherein the recommended degree of the simulation irrigation parameter is the sum of the recommended degree of the first time zone and the recommended degree of the second time zone.

[0013] Optionally, the selecting the target fertilization time and the target fertilization amount in the soil water content target curve according to the preset fertilization standard includes: Obtain the rainfall prediction duration of the current rainfall prediction curve and the fertilization stage duration of the current fertilization stage; Calculate the number of fertilization nodes according to the duration of the fertilization stage and the duration of rainfall prediction using the following formula: ; Wherein, represents the number of fertilization nodes, represents the floor function symbol, represents the duration of the fertilization stage, represents the duration of rainfall prediction; Obtain the total fertilization amount of the current fertilization stage; Calculate the target fertilization amount according to the number of fertilization nodes and the total fertilization amount, wherein the target fertilization amount is equal to the ratio of the total fertilization amount to the number of fertilization nodes; Set the target fertilization time equidistantly within the preset current fertilization period according to the number of fertilization nodes.

[0014] To achieve the above object, the present invention also provides a water and fertilizer utilization efficiency optimization system for integrated water and fertilizer management in corn fields, comprising: A soil lower limit water content judgment module, configured to obtain the optimal soil water content range corresponding to the current fertilization stage, identify the soil lower limit water content in the optimal soil water content range; obtain the current rainfall prediction curve, perform soil water content prediction according to the current rainfall prediction curve to obtain a soil water content prediction curve; judge whether the soil lower limit water content exists in the soil water content prediction curve; if the soil lower limit water content does not exist in the soil water content prediction curve, return to the step of obtaining the current rainfall prediction curve above; An irrigation parameter determination module, configured to, if the soil lower limit water content exists in the soil water content prediction curve, determine the irrigation selection period according to the soil lower limit water content, wherein the end point of the irrigation selection period is the time point corresponding to the soil lower limit water content; determine the simulated irrigation parameters according to the irrigation selection period, perform soil irrigation simulation using the simulated irrigation parameters and the soil water content prediction curve to obtain a set of soil water content simulation curves, wherein the simulated irrigation parameters include: simulated irrigation time points, simulated irrigation water volumes; select a target soil water content curve from the set of soil water content simulation curves according to the preset soil water content standard, and identify the target irrigation time point and target irrigation water volume corresponding to the target soil water content curve; A fertilization parameter determination module, configured to select the target fertilization time and target fertilization amount from the target soil water content curve according to the preset fertilization standard; An integrated fertilization module, configured to perform fertilization in the corn field according to the target irrigation time point, target irrigation water volume, target fertilization time and target fertilization amount.

[0015] To solve the above problems, the present invention also provides an electronic device, the electronic device comprising: A memory that stores at least one instruction; and a processor that executes the instruction stored in the memory to implement the method for optimizing the water and fertilizer utilization efficiency of integrated water and fertilizer in a corn field as described above.

[0016] To solve the above problems, the present invention also provides a computer-readable storage medium, in which at least one instruction is stored, and the at least one instruction is executed by a processor in an electronic device to implement the method for optimizing the water and fertilizer utilization efficiency of integrated water and fertilizer in a corn field as described above.

[0017] To solve the problems described in the background art, the present invention first uses the lower limit soil water content to determine whether irrigation is required. Since obtaining the lower limit soil water content requires predicting the soil water content of the corn field, it is necessary to first obtain the optimal soil water content interval corresponding to the current fertilization stage, and then identify the lower limit soil water content in the optimal soil water content interval. At this time, it is necessary to obtain the current rainfall prediction curve, and then perform soil water content prediction according to the current rainfall prediction curve to obtain the soil water content prediction curve. At this time, it can be determined whether the lower limit soil water content exists in the soil water content prediction curve. If the lower limit soil water content does not exist in the soil water content prediction curve, it indicates that irrigation is not required, so directly return to the step of obtaining the current rainfall prediction curve above. If the lower limit soil water content exists in the soil water content prediction curve, it indicates that irrigation is required. Since it is necessary to first determine the irrigation time point, the irrigation selection period can be determined according to the lower limit soil water content, and then the simulated irrigation parameters can be determined according to the irrigation selection period. In order to identify the target irrigation time point and the target irrigation water volume, it is necessary to use the simulated irrigation parameters and the soil water content prediction curve to perform soil irrigation simulation to obtain a set of soil water content simulation curves, and then select the target soil water content curve in the set of soil water content simulation curves according to the preset soil water content standard, so as to identify the target irrigation time point and the target irrigation water volume corresponding to the target soil water content curve. When the target irrigation time point and the target irrigation water volume are determined, it is necessary to select the target fertilization time and the target fertilization amount in the target soil water content curve according to the preset fertilization standard, and finally perform fertilization on the corn field according to the target irrigation time point, the target irrigation water volume, the target fertilization time and the target fertilization amount, so as to complete the optimization of the water and fertilizer utilization efficiency of integrated water and fertilizer in the corn field. Therefore, the present invention can improve the water and fertilizer efficiency and regulation accuracy of current integrated water and fertilizer fertilization in corn fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flowchart showing the method for optimizing the water and fertilizer utilization efficiency of integrated water and fertilizer in a corn field provided by an embodiment of the present invention; Figure 2 It is a functional module diagram of the system for optimizing the water and fertilizer utilization efficiency of integrated water and fertilizer in a corn field provided by an embodiment of the present invention; Figure 3 Schematic structural diagram of an electronic device for implementing the optimization method of water and fertilizer utilization efficiency of integrated water and fertilizer in corn fields according to an embodiment of the present invention.

[0019] Description of reference numerals: 1. Electronic device; 10. Processor; 11. Memory; 12. Bus.

[0020] The realization, functional characteristics and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0021] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] An embodiment of the present application provides an optimization method for water and fertilizer utilization efficiency of integrated water and fertilizer in corn fields. The execution subject of the optimization method for water and fertilizer utilization efficiency of integrated water and fertilizer in corn fields includes, but is not limited to, at least one of electronic devices such as a server, a terminal, etc. that can be configured to execute the method provided in the embodiments of the present application. In other words, the optimization method for water and fertilizer utilization efficiency of integrated water and fertilizer in corn fields can be executed by software or hardware installed on a terminal device or a server device, and the software can be a blockchain platform. The server includes, but is not limited to: a single server, a server cluster, a cloud server, or a cloud server cluster, etc.

[0023] Refer to Figure 1 As shown, it is a flowchart of an optimization method for water and fertilizer utilization efficiency of integrated water and fertilizer in corn fields provided by an embodiment of the present invention. In this embodiment, the optimization method for water and fertilizer utilization efficiency of integrated water and fertilizer in corn fields includes: S1. Obtain the optimal soil water content range corresponding to the current fertilization stage, and identify the lower limit soil water content in the optimal soil water content range.

[0024] It can be understood that the current fertilization stage refers to the fertilization stage where the current corn field is located, and the fertilization stage includes: seedling stage, jointing stage, tasseling stage, filling stage, maturity stage. The optimal soil water content range refers to the optimal soil water content range of the current fertilization stage. For example: when the current fertilization stage is the seedling stage, the optimal soil water content range can be 16% - 20%; when the current fertilization stage is the jointing stage, the optimal soil water content range can be 22 - 26%; when the current fertilization stage is the tasseling stage, the optimal soil water content range can be 22 - 26%. The lower limit soil water content refers to the lowest water content in the optimal soil water content range. For example: when the optimal soil water content range is 16% - 20%, the lower limit soil water content is 16%.

[0025] S2. Obtain the current rainfall prediction curve, and perform soil water content prediction according to the current rainfall prediction curve to obtain a soil water content prediction curve.

[0026] Interpretably, the current rainfall prediction curve refers to the rainfall prediction curve graph of the area where the corn field is located at the current time. For example, if the current time is January 1st, the prediction time of the current rainfall prediction curve can be from January 1st to January 7th, that is, the rainfall prediction duration of the current rainfall prediction curve is one week. The soil water content prediction curve refers to the graph of the change in soil water content of the corn field predicted under the current rainfall prediction curve.

[0027] In the embodiment of the present invention, the performing soil water content prediction according to the current rainfall prediction curve to obtain a soil water content prediction curve includes: Obtain the current soil water content, and calculate the current soil water storage according to the current soil water content by using the following formula: ; Wherein, represents the current soil water storage, represents the current soil water content, represents the soil bulk density, represents the soil layer depth; Extract the first predicted rainfall in the current rainfall prediction curve, wherein the first predicted rainfall refers to the rainfall predicted for the next day in the current rainfall prediction curve; Judge whether the first predicted rainfall is 0; If the first predicted rainfall is 0, then calculate the iterative soil water storage by using a pre-constructed first soil water storage formula and a preset crop evapotranspiration amount and a reference deep percolation amount. The first soil water storage formula is as follows: ; Wherein, represents the iterative soil water storage, represents the crop evapotranspiration amount, represents the reference deep percolation amount, represents the field capacity; If the first predicted rainfall is not 0, then calculate the first surface runoff by using a pre-constructed surface runoff formula according to the first predicted rainfall; Calculate the first deep percolation amount by using a pre-constructed deep percolation amount formula according to a preset unsaturated hydraulic conductivity; Calculate the iterative soil water storage by using a pre-constructed second soil water storage formula according to the current soil water storage, the first predicted rainfall, the first surface runoff, the first deep percolation amount and the crop evapotranspiration amount. The second soil water storage formula is as follows: ; Wherein, represents the first predicted rainfall amount, represents the first surface runoff amount, represents the first deep percolation amount; Using the iterative soil water storage, calculate the iterative soil water content using the following formula: ; Wherein, represents the iterative soil water content; Judge whether there is a preset predicted rainfall amount for the next day for the first predicted rainfall amount, wherein the predicted rainfall amount for the next day refers to the predicted rainfall amount on the day after the first predicted rainfall amount; If there is a predicted rainfall amount for the next day for the first predicted rainfall amount, identify the predicted rainfall amount for the next day of the first predicted rainfall amount; Update the current soil water storage and the first predicted rainfall amount respectively using the iterative soil water storage and the predicted rainfall amount for the next day, and return to the above step of judging whether the first predicted rainfall amount is 0; If there is no predicted rainfall amount for the next day for the first predicted rainfall amount, draw a soil water content prediction curve according to the current soil water content and the iterative soil water content.

[0028] Furthermore, the current soil water content refers to the water content of the corn field soil at the current time. The current soil water storage refers to the soil water storage corresponding to the preset soil layer depth of the corn field soil at the current time. The soil layer depth can be 60 cm. The soil bulk density can be 1.35 . For example, when the current rainfall prediction curve is the rainfall prediction curve from January 1st to January 7th, the first predicted rainfall amount is the predicted rainfall amount on January 1st. Since there may be days without rainfall during the prediction period, therefore, the first predicted rainfall amount may be 0. When the first predicted rainfall amount is 0, there will be no surface runoff amount in the first soil water storage formula.

[0029] It can be explained that the iterative soil water storage refers to the soil water storage of each future day during the prediction period calculated according to the current rainfall prediction curve. The crop evapotranspiration amount can be set to 5 mm / day. The reference deep percolation amount refers to the deep percolation amount when the first predicted rainfall amount is 0, which can be set to 15 mm / day. The field capacity can be set to 28%. Only when the current soil water content is greater than the field capacity, there will be deep percolation. Therefore, when the reference deep percolation amount does not exist in the calculation formula of the iterative soil water storage.

[0030] It is understandable that the first surface runoff refers to the surface runoff volume under the first predicted rainfall. The unsaturated hydraulic conductivity can be set to 15 mm / day. The first deep percolation volume refers to the deep percolation volume under the first predicted rainfall. Since there is surface runoff when the first predicted rainfall is not 0, therefore, compared with the first soil water storage formula, the second soil water storage formula has the first surface runoff volume and the first predicted rainfall.

[0031] Furthermore, the iterative soil water content refers to the soil water content of each future day during the prediction period calculated according to the current rainfall prediction curve. For example, when the first predicted rainfall is the predicted rainfall on January 1st, the day-after prediction rainfall is the predicted rainfall on January 2nd. Since when the current rainfall prediction curve is the rainfall prediction curve from January 1st to January 7th, and the date corresponding to the updated first predicted rainfall is January 7th, there is no day-after prediction rainfall for the first predicted rainfall.

[0032] In the embodiment of the present invention, the surface runoff formula is as follows: ; Wherein, represents the number of curves.

[0033] It is understandable that when the corn field is flat-tilled, the number of curves can take the value of 75, and when the corn field is ridge-tilled and covered, the number of curves can take the value of 65.

[0034] In the embodiment of the present invention, the deep percolation volume formula is as follows: ; Wherein, represents the unsaturated hydraulic conductivity, represents the hydraulic gradient.

[0035] Furthermore, the hydraulic gradient can take the value of 1.

[0036] S3. Determine whether the soil water content prediction curve has the soil lower limit water content.

[0037] It is understandable that since the soil water content prediction curve changes continuously under the influence of factors such as the current rainfall prediction curve, therefore, at one or more time points during the change process, the soil water content corresponding to the soil water content prediction curve may be equal to the soil lower limit water content.

[0038] If the soil water content prediction curve does not have the soil lower limit water content, return to the above step of obtaining the current rainfall prediction curve.

[0039] If there is a lower soil water content in the soil water content prediction curve, then execute S4 to determine the irrigation selection period according to the lower soil water content, where the end point of the irrigation selection period is the time point corresponding to the lower soil water content.

[0040] It can be understood that when there is a lower soil water content in the soil water content prediction curve, it indicates that the water content of the soil cannot meet the requirements of the current fertilization stage. Therefore, artificial irrigation is required. The irrigation selection period refers to the period before the time point corresponding to the lower soil water content during the rainfall prediction period. For example, when the prediction time of the current rainfall prediction curve can be from January 1st to January 7th, and the time point corresponding to the lower soil water content is 16:00 on January 5th, then the irrigation selection period is from January 1st to 16:00 on January 5th.

[0041] In the embodiment of the present invention, determining the irrigation selection period according to the lower soil water content includes: Judging whether there is only one lower soil water content in the soil water content prediction curve; If there is only one lower soil water content in the soil water content prediction curve, then identify the soil water content prediction time point corresponding to the lower soil water content; If there is more than one lower soil water content in the soil water content prediction curve, then identify the first lower water content in the soil water content prediction curve, where the first lower water content refers to the first lower soil water content in the soil water content prediction curve; Identify the soil water content prediction time point corresponding to the first lower water content; Obtain the current time point, and determine the irrigation selection period according to the current time point and the soil water content prediction time point.

[0042] Furthermore, the soil water content prediction time point refers to the time point corresponding to the lower soil water content.

[0043] S5. Determine the simulated irrigation parameters according to the irrigation selection period, and use the simulated irrigation parameters and the soil water content prediction curve to perform soil irrigation simulation to obtain a set of soil water content simulation curves, where the simulated irrigation parameters include: simulated irrigation time point, simulated irrigation water volume.

[0044] It can be understood that the simulated irrigation parameters refer to the irrigation parameters during the soil simulated irrigation process. The simulated irrigation water volume refers to the irrigation water level volume per unit area. For example, when the irrigation water volume per unit area of the simulated irrigation water volume is 1 , the irrigation water level volume is 1 mm. The set of soil water content simulation curves refers to the curve set formed according to the soil water content prediction curve under the influence of the simulated irrigation parameters.

[0045] In the embodiments of the present invention, determining the simulated irrigation parameters according to the selected irrigation time period, and performing soil irrigation simulation by using the simulated irrigation parameters and the soil water content prediction curve to obtain a set of soil water content simulation curves, including: Selecting a set of simulated irrigation time points at preset time intervals within the selected irrigation time period, and sequentially selecting simulated irrigation time points from the set of simulated irrigation time points, Identifying the simulated irrigation date corresponding to the simulated irrigation time point; Identifying the simulated predicted rainfall corresponding to the simulated irrigation date in the current rainfall prediction curve; Obtaining a set of simulated irrigation water volumes, sequentially extracting simulated irrigation water volumes from the set of simulated irrigation water volumes, and updating the first soil water storage formula and the second soil water storage formula by using the simulated irrigation water volumes. Among them, the updated first soil water storage formula is as follows: ; Wherein, represents the simulated irrigation water volume; The updated second soil water storage formula is as follows: ; Updating the first predicted rainfall by using the simulated predicted rainfall, and returning to the above step of judging whether the first predicted rainfall is 0 to obtain the soil water content simulation curve corresponding to the simulated irrigation parameters; Collecting the soil water content simulation curves corresponding to each simulated irrigation parameter to obtain a set of soil water content simulation curves.

[0046] It can be understood that when the selected irrigation time period is from January 1st to 16:00 on January 5th, the set of simulated irrigation time points can be selected as 16:00 on January 1st, 16:00 on January 2nd, 16:00 on January 3rd, 16:00 on January 4th, and 16:00 on January 5th. The simulated irrigation date refers to the date corresponding to the simulated irrigation time point, and the simulated predicted rainfall refers to the predicted rainfall corresponding to the simulated irrigation date in the current rainfall prediction curve. The set of simulated irrigation water volumes refers to the set of irrigation water volumes preset for soil simulated irrigation.

[0047] S6. Selecting a target soil water content curve from the set of soil water content simulation curves according to a preset soil water content standard, and identifying the target irrigation time point and the target irrigation water volume corresponding to the target soil water content curve.

[0048] It is understandable that the soil water content standard refers to a preset standard for measuring the quality of the soil water content simulation curve. The soil water content target curve refers to the best soil water content simulation curve in the set of soil water content simulation curves. The target irrigation time point refers to the simulated irrigation time point corresponding to the soil water content target curve, and the target irrigation water volume refers to the simulated irrigation water volume corresponding to the soil water content target curve.

[0049] In an embodiment of the present invention, the selection of the soil water content target curve from the set of soil water content simulation curves according to the preset soil water content standard includes: Sequentially extract the soil water content simulation curves from the set of soil water content simulation curves; Determine the intermediate soil water content according to the best soil water content interval, where the intermediate soil water content refers to the median value of the best soil water content interval; Construct an intermediate soil water content line segment according to the intermediate soil water content; Determine whether there is an intersection between the soil water content simulation curve and the intermediate soil water content line segment; If there is no intersection between the soil water content simulation curve and the intermediate soil water content line segment, then determine whether the soil water content simulation curve is above the intermediate soil water content line segment; If the soil water content simulation curve is above the intermediate soil water content line segment, then calculate the recommended degree of simulation irrigation parameters using the following formula: ; Wherein, represents the recommended degree of simulation irrigation parameters, represents the first recommended weight, represents the integral area of the soil water content simulation curve, represents the integral area of the intermediate soil water content line segment; If the soil water content simulation curve is not above the intermediate soil water content line segment, then calculate the recommended degree of simulation irrigation parameters using the following formula: ; Wherein, represents the second recommended weight; If there is an intersection between the soil water content simulation curve and the intermediate soil water content line segment, then use the intersection to divide the soil water content simulation curve and the intermediate soil water content line segment to obtain a first time zone line pair and a second time zone line pair; Calculate the recommended degree of simulation irrigation parameters according to the first time zone line pair and the second time zone line pair; Collect the recommended degrees of the simulated irrigation parameters corresponding to each soil water content simulation curve to obtain a set of recommended degrees of the simulated irrigation parameters. Identify the maximum recommended degree of the simulated irrigation parameters in the set of recommended degrees of the simulated irrigation parameters, and identify the soil water content target curve corresponding to the maximum recommended degree of the simulated irrigation parameters.

[0050] Further, when the optimal soil water content range is 16% - 20%, the intermediate soil water content is 18%. The intermediate soil water content line segment refers to the line segment indicating that the soil water content is always 18% within the predicted time in the coordinate system with the abscissa representing time and the ordinate representing soil water content. The recommended degree of the simulated irrigation parameter refers to the recommended degree of selecting the soil water content simulation curve as the soil water content target curve. The first recommended weight can take a value of 0.6, and the second recommended weight can take a value of 0.4. The integral area refers to the integral area of the soil water content simulation curve or the intermediate soil water content line segment with respect to time. The first time zone line pair refers to the partial soil water content simulation curve and the partial intermediate soil water content line segment located on the left side of the intersection point after being segmented by the intersection point. The second time zone line pair refers to the partial soil water content simulation curve and the partial intermediate soil water content line segment located on the right side of the intersection point after being segmented by the intersection point.

[0051] In the embodiment of the present invention, calculating the recommended degree of the simulated irrigation parameter according to the first time zone line pair and the second time zone line pair includes: Identify the first target recommended weight of the first time zone line pair and the second target recommended weight of the second time zone line pair respectively; Calculate the first area absolute difference and the second area absolute difference of the first time zone line pair and the second time zone line pair respectively; Calculate the first time zone recommended degree according to the first target recommended weight and the first area absolute difference, and calculate the second time zone recommended degree according to the second target recommended weight and the second area absolute difference; Calculate the recommended degree of the simulated irrigation parameter according to the first time zone recommended degree and the second time zone recommended degree, where the recommended degree of the simulated irrigation parameter is the sum of the first time zone recommended degree and the second time zone recommended degree.

[0052] It is understandable that the first target recommendation weight refers to the recommendation weight determined according to the vertical relationship between the partial soil water content simulation curve and the partial soil water content intermediate line segment in the first time zone pair. When the partial soil water content simulation curve in the first time zone pair is above the partial soil water content intermediate line segment, the first target recommendation weight is equal to the first recommendation weight; when the partial soil water content simulation curve in the first time zone pair is below the partial soil water content intermediate line segment, the first target recommendation weight is equal to the second recommendation weight. The second target recommendation weight refers to the recommendation weight determined according to the vertical relationship between the partial soil water content simulation curve and the partial soil water content intermediate line segment in the second time zone pair, and the determination method is the same as that of the first target recommendation weight, which will not be elaborated here.

[0053] Furthermore, the first area absolute difference refers to the absolute value of the integral area difference between the partial soil water content simulation curve and the partial soil water content intermediate line segment in the first time zone pair. The second area absolute difference refers to the absolute value of the integral area difference between the partial soil water content simulation curve and the partial soil water content intermediate line segment in the second time zone pair. The first time zone recommendation degree refers to the recommendation degree of selecting the soil water content simulation curve corresponding to the first time zone pair as the soil water content target curve, and the second time zone recommendation degree refers to the recommendation degree of selecting the soil water content simulation curve corresponding to the second time zone pair as the soil water content target curve.

[0054] S7. Select the target fertilization time and target fertilization amount from the soil water content target curve according to the preset fertilization standard.

[0055] It is understandable that the fertilization standard refers to the standard for determining the target fertilization time and target fertilization amount according to the soil water content target curve. The target fertilization time refers to the time for fertilization, and the target fertilization amount refers to the fertilization amount at the target fertilization time.

[0056] In the embodiment of the present invention, the step of selecting the target fertilization time and target fertilization amount from the soil water content target curve according to the preset fertilization standard includes: Obtain the rainfall prediction duration of the current rainfall prediction curve and the fertilization stage duration of the current fertilization stage; Use the following formula to calculate the number of fertilization nodes according to the fertilization stage duration and the rainfall prediction duration: ; where represents the number of fertilization nodes, represents the floor function symbol, represents the fertilization stage duration, represents the rainfall prediction duration; Obtain the total fertilization amount of the current fertilization stage; Calculate the target fertilization amount according to the number of fertilization nodes and the total fertilization amount, where the target fertilization amount is equal to the ratio of the total fertilization amount to the number of fertilization nodes; Set the target fertilization time at equal intervals within the preset current fertilization period according to the number of fertilization nodes.

[0057] It can be understood that the rainfall prediction duration refers to the prediction time length of the current rainfall prediction curve. For example, when the current rainfall prediction curve is the rainfall prediction curve from January 1st to January 7th, the rainfall prediction duration is h. The fertilization stage duration refers to the stage duration of the current fertilization stage. For example, when the current fertilization stage is the jointing stage, the fertilization stage duration can be 20 days (i.e., h). The number of fertilization nodes refers to the number of times of fertilization in the current fertilization stage.

[0058] S8. Perform corn field fertilization according to the target irrigation time point, target irrigation water volume, target fertilization time, and target fertilization amount to complete the optimization of the water and fertilizer utilization efficiency of the water and fertilizer integration in the corn field.

[0059] It can be understood that when the target irrigation time point is 16:00 on January 5th, the target irrigation water volume is 1 mm, the target fertilization time is 15:00 on January 3rd, and the target fertilization amount is 1 kg urea / mu (or 2 kg / mu nitrogen, phosphorus, and potassium compound fertilizer, etc.), corn field fertilization can be carried out according to the target irrigation time point, target irrigation water volume, target fertilization time, and target fertilization amount.

[0060] To solve the problems described in the background art, the present invention first uses the lower limit soil water content to determine whether irrigation is required. Since obtaining the lower limit soil water content requires predicting the soil water content of the corn field, it is necessary to first obtain the optimal soil water content range corresponding to the current fertilization stage, and then identify the lower limit soil water content within the optimal soil water content range. At this time, it is necessary to obtain the current rainfall prediction curve, and then perform soil water content prediction according to the current rainfall prediction curve to obtain the soil water content prediction curve. At this time, it can be determined whether the lower limit soil water content exists in the soil water content prediction curve. If the lower limit soil water content does not exist in the soil water content prediction curve, it indicates that irrigation is not required, so the step of obtaining the current rainfall prediction curve is directly returned. If the lower limit soil water content exists in the soil water content prediction curve, it indicates that irrigation is required. Since it is necessary to first determine the irrigation time point, the irrigation selection period can be determined according to the lower limit soil water content, and then the simulated irrigation parameters can be determined according to the irrigation selection period. In order to identify the target irrigation time point and the target irrigation water volume, it is necessary to use the simulated irrigation parameters and the soil water content prediction curve to perform soil irrigation simulation to obtain a set of soil water content simulation curves, and then select the target soil water content curve in the set of soil water content simulation curves according to the preset soil water content standard, so as to identify the target irrigation time point and the target irrigation water volume corresponding to the target soil water content curve. After determining the target irrigation time point and the target irrigation water volume, it is necessary to select the target fertilization time and the target fertilization amount in the target soil water content curve according to the preset fertilization standard, and finally perform fertilization on the corn field according to the target irrigation time point, the target irrigation water volume, the target fertilization time and the target fertilization amount, so as to complete the optimization of the water and fertilizer utilization efficiency of the water and fertilizer integration in the corn field. Therefore, the present invention can improve the water and fertilizer efficiency and regulation accuracy of the current water and fertilizer integration fertilization in the corn field.

[0061] As Figure 2 shown, it is a functional module diagram of a system for optimizing the water and fertilizer utilization efficiency of water and fertilizer integration in a corn field provided by an embodiment of the present invention.

[0062] The system 100 for optimizing the water and fertilizer utilization efficiency of water and fertilizer integration in the corn field according to the present invention can be installed in an electronic device. According to the functions to be realized, the system 100 for optimizing the water and fertilizer utilization efficiency of water and fertilizer integration in the corn field can include a lower limit soil water content judgment module 101, an irrigation parameter determination module 102, a fertilization parameter determination module 103, and an integrated fertilization module 104. The modules in the present invention can also be referred to as units, which refer to a series of computer program segments that can be executed by a processor of an electronic device and can complete fixed functions, and are stored in the memory of the electronic device.

[0063] The soil lower limit water content judgment module 101 is used to obtain the optimal soil water content range corresponding to the current fertilization stage, identify the soil lower limit water content in the optimal soil water content range; obtain the current rainfall prediction curve, predict the soil water content according to the current rainfall prediction curve to obtain a soil water content prediction curve; judge whether the soil lower limit water content exists in the soil water content prediction curve; if the soil lower limit water content does not exist in the soil water content prediction curve, return to the step of obtaining the current rainfall prediction curve above; The irrigation parameter determination module 102 is used to, if the soil lower limit water content exists in the soil water content prediction curve, determine the irrigation selection period according to the soil lower limit water content, where the end point of the irrigation selection period is the time point corresponding to the soil lower limit water content; determine the simulated irrigation parameters according to the irrigation selection period, and perform soil irrigation simulation using the simulated irrigation parameters and the soil water content prediction curve to obtain a set of soil water content simulation curves, where the simulated irrigation parameters include: simulated irrigation time points, simulated irrigation water volumes; select a soil water content target curve from the set of soil water content simulation curves according to a preset soil water content standard, and identify the target irrigation time point and target irrigation water volume corresponding to the soil water content target curve; The fertilization parameter determination module 103 is used to select the target fertilization time and target fertilization amount in the soil water content target curve according to a preset fertilization standard; The integrated fertilization module 104 is used to select the target fertilization time and target fertilization amount in the soil water content target curve according to a preset fertilization standard.

[0064] Specifically, each module in the water and fertilizer utilization efficiency optimization system 100 for integrated water and fertilizer management in corn fields in the embodiments of the present invention adopts the same technical means as those in the above-mentioned Figure 1 The water and fertilizer utilization efficiency optimization method for integrated water and fertilizer management in corn fields described, and can produce the same technical effects, which will not be elaborated here.

[0065] As Figure 3 shown, it is a schematic structural diagram of an electronic device for implementing the water and fertilizer utilization efficiency optimization method for integrated water and fertilizer management in corn fields provided by an embodiment of the present invention.

[0066] The electronic device 1 may include a processor 10, a memory 11, and a bus 12, and may further include a computer program stored in the memory 11 and executable on the processor 10, such as a water and fertilizer utilization efficiency optimization method program for integrated water and fertilizer management in corn fields.

[0067] Among them, the memory 11 includes at least one type of readable storage medium, and the readable storage medium includes flash memory, mobile hard disk, multimedia card, card-type memory (such as SD or DX memory, etc.), magnetic memory, magnetic disk, optical disc, etc. The memory 11 can be an internal storage unit of the electronic device 1 in some embodiments, such as the mobile hard disk of the electronic device 1. The memory 11 can also be an external storage device of the electronic device 1 in some other embodiments, such as a plug-in mobile hard disk, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc. equipped on the electronic device 1. Further, the memory 11 also includes the internal storage unit of the electronic device 1 and also includes an external storage device. The memory 11 can be used not only to store application software installed in the electronic device 1 and various types of data, such as the code of the method program for optimizing the water and fertilizer utilization efficiency of the integrated water and fertilizer in the corn field, etc., but also to temporarily store the data that has been output or will be output.

[0068] The processor 10 can be composed of integrated circuits in some embodiments. For example, it can be composed of a single packaged integrated circuit, or can be composed of multiple integrated circuits with the same or different functions packaged together, including the combination of one or more Central Processing Units (CPUs), microprocessors, digital processing chips, graphics processors, and various control chips, etc. The processor 10 is the control core (Control Unit) of the electronic device, connecting various components of the entire electronic device through various interfaces and lines, and by running or executing the programs or modules stored in the memory 11 (such as the method program for optimizing the water and fertilizer utilization efficiency of the integrated water and fertilizer in the corn field, etc.), and calling the data stored in the memory 11, to execute various functions of the electronic device 1 and process data.

[0069] The bus 12 can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This bus 12 can be divided into an address bus, a data bus, a control bus, etc. The bus 12 is set to realize the connection and communication between the memory 11 and at least one processor 10, etc.

[0070] Figure 3 Only the electronic device with components is shown. Those skilled in the art can understand that, Figure 3The structures shown do not constitute a limitation on the electronic device 1, and it may include fewer or more components than shown, or combine certain components, or have different component arrangements.

[0071] For example, although not shown, the electronic device 1 may further include a power source (such as a battery) for supplying power to each component. Preferably, the power source can be logically connected to the at least one processor 10 through a power management device, so as to implement functions such as charge management, discharge management, and power consumption management through the power management device. The power source may also include any components such as one or more DC or AC power sources, a recharge device, a power failure detection circuit, a power converter or inverter, and a power status indicator. The electronic device 1 may also include various sensors, a Bluetooth module, a Wi-Fi module, etc., which will not be elaborated here.

[0072] Furthermore, the electronic device 1 may further include a network interface. Optionally, the network interface may include a wired interface and / or a wireless interface (such as a WI-FI interface, a Bluetooth interface, etc.), which is generally used to establish a communication connection between the electronic device 1 and other electronic devices.

[0073] Optionally, the electronic device 1 may further include a user interface. The user interface may be a display, an input unit (such as a keyboard), and optionally, the user interface may also be a standard wired interface or a wireless interface. Optionally, in some embodiments, the display may be an LED display, a liquid crystal display, a touch liquid crystal display, and an OLED (Organic Light-Emitting Diode) toucher, etc. Among them, the display may also be appropriately referred to as a display screen or a display unit, which is used to display the information processed in the electronic device 1 and to display a visual user interface.

[0074] The program for optimizing the water and fertilizer utilization efficiency of the integrated water and fertilizer in the corn field stored in the memory 11 of the electronic device 1 is a combination of multiple instructions. When running in the processor 10, it can implement: Obtain the optimal soil water content range corresponding to the current fertilization stage, and identify the lower limit soil water content in the optimal soil water content range; Obtain the current rainfall prediction curve, perform soil water content prediction according to the current rainfall prediction curve, and obtain a soil water content prediction curve; Judge whether the lower limit soil water content exists in the soil water content prediction curve; If the lower limit soil water content does not exist in the soil water content prediction curve, return to the step of obtaining the current rainfall prediction curve above; If the soil water content prediction curve has a lower limit of soil water content, determine the irrigation selection period according to the lower limit of soil water content, where the end point of the irrigation selection period is the time point corresponding to the lower limit of soil water content; Determine the simulated irrigation parameters according to the irrigation selection period, and perform soil irrigation simulation using the simulated irrigation parameters and the soil water content prediction curve to obtain a set of soil water content simulation curves, where the simulated irrigation parameters include: simulated irrigation time points and simulated irrigation water volumes; Select a target soil water content curve from the set of soil water content simulation curves according to a preset soil water content standard, and identify the target irrigation time point and target irrigation water volume corresponding to the target soil water content curve; Select the target fertilization time and target fertilization amount from the target soil water content curve according to a preset fertilization standard; Perform fertilization on the corn field according to the target irrigation time point, target irrigation water volume, target fertilization time, and target fertilization amount to complete the optimization of the water and fertilizer utilization efficiency of the water and fertilizer integration in the corn field.

[0075] Specifically, the specific implementation method of the above instructions by the processor 10 can refer to Figures 1 to 3 the description of the relevant steps in the corresponding embodiment, which will not be elaborated here.

[0076] Further, if the module / unit integrated in the electronic device 1 is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. The computer-readable storage medium can be volatile or non-volatile. For example, the computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a mobile hard disk, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM, Read-Only Memory).

[0077] The present invention also provides a computer-readable storage medium, where the readable storage medium stores a computer program, and when the computer program is executed by a processor of an electronic device, it can implement: Obtain the optimal soil water content range corresponding to the current fertilization stage, and identify the lower limit of soil water content in the optimal soil water content range; Obtain the current rainfall prediction curve, and perform soil water content prediction according to the current rainfall prediction curve to obtain a soil water content prediction curve; Determine whether the soil water content prediction curve has the lower limit of soil water content; If the soil water content prediction curve does not have the lower limit of soil water content, return to the step of obtaining the current rainfall prediction curve above; If there is a lower soil water content in the predicted soil water content curve, determine the irrigation selection period according to the lower soil water content, where the end point of the irrigation selection period is the time point corresponding to the lower soil water content; Determine the simulated irrigation parameters according to the irrigation selection period, and perform soil irrigation simulation using the simulated irrigation parameters and the predicted soil water content curve to obtain a set of simulated soil water content curves, where the simulated irrigation parameters include: simulated irrigation time points and simulated irrigation water volumes; Select the target soil water content curve from the set of simulated soil water content curves according to the preset soil water content standard, and identify the target irrigation time point and target irrigation water volume corresponding to the target soil water content curve; Select the target fertilization time and target fertilization amount from the target soil water content curve according to the preset fertilization standard; Perform fertilization on the corn field according to the target irrigation time point, target irrigation water volume, target fertilization time, and target fertilization amount to complete the optimization of the water and fertilizer utilization efficiency of the water and fertilizer integration in the corn field.

[0078] In several embodiments provided by the present invention, it should be understood that the disclosed devices, systems, and methods can be implemented in other ways. For example, the system embodiments described above are only illustrative, and there can be other division methods in actual implementation.

[0079] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical units, that is, they can be located in one place, or they can be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0080] In addition, the functional modules in each embodiment of the present invention can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above integrated units can be implemented in the form of hardware, or in the form of hardware plus software functional modules.

[0081] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for optimizing water and fertilizer utilization efficiency of corn fields with integrated water and fertilizer, characterized in that: The method comprises: Obtaining an optimal soil moisture range corresponding to the current fertilization stage, and identifying a lower limit of soil moisture in the optimal soil moisture range; Obtaining a current rainfall prediction curve, and performing soil moisture prediction according to the current rainfall prediction curve to obtain a soil moisture prediction curve; Determine whether the soil moisture prediction curve has the soil lower limit moisture content; If the soil moisture prediction curve does not have a lower limit of soil moisture content, return to the above step of obtaining the current rainfall prediction curve; If the soil moisture prediction curve has a lower limit of soil moisture content, the irrigation selection period is determined according to the lower limit of soil moisture content, wherein the end point of the irrigation selection period is the time point corresponding to the lower limit of soil moisture content; Determine simulated irrigation parameters according to the irrigation selection period, perform soil irrigation simulation using the simulated irrigation parameters and the soil moisture prediction curve, and obtain a soil moisture simulation curve set, wherein the simulated irrigation parameters include: simulated irrigation time point and simulated irrigation water volume; Selecting a soil moisture target curve from the soil moisture simulation curve set according to a preset soil moisture standard, and identifying a target irrigation time point and a target irrigation water volume corresponding to the soil moisture target curve; Selecting a target fertilization time and a target fertilization amount from the soil moisture target curve according to a preset fertilization standard; The corn field is fertilized according to the target irrigation time point, target irrigation water volume, target fertilization time and target fertilization volume, thereby optimizing the water and fertilizer utilization efficiency of the corn field through integrated water and fertilizer integration.

2. The method for optimizing water and fertilizer utilization efficiency of corn fields according to claim 1, characterized in that: The step of performing soil moisture prediction according to the current rainfall prediction curve to obtain the soil moisture prediction curve includes: The current soil moisture content is obtained, and the current soil water storage capacity is calculated according to the current soil moisture content using the following formula: ； in, Indicates the current soil water storage capacity, Indicates the current soil moisture content. It represents the soil bulk density. Indicates the depth of soil layer; Extracting a first predicted rainfall from the current rainfall prediction curve, wherein the first predicted rainfall refers to the rainfall predicted for the next day from the current rainfall prediction curve; Determining whether the first predicted rainfall is 0; If the first predicted rainfall is 0, the iterative soil water storage is calculated using the pre-constructed first soil water storage formula, the preset crop evapotranspiration, and the reference deep infiltration, wherein the first soil water storage formula is as follows: ； in, represents the iterative soil water storage, is the crop evapotranspiration, Indicates the reference deep leakage, It indicates field capacity; If the first predicted rainfall is not 0, calculating a first surface runoff amount using a pre-constructed surface runoff formula according to the first predicted rainfall; According to the preset unsaturated hydraulic conductivity, the first deep layer leakage is calculated using the pre-constructed deep layer leakage formula; According to the current soil water storage, the first predicted rainfall, the first surface runoff, the first deep seepage and the crop evapotranspiration, the iterative soil water storage is calculated using a pre-constructed second soil water storage formula, wherein the second soil water storage formula is as follows: ； in, represents the first predicted rainfall, represents the first surface runoff, Indicates the first deep layer leakage; Using the iterative soil water storage, the iterative soil water content is calculated using the following formula: ； in, represents the iterated soil moisture content; Determine whether the first predicted rainfall has a preset predicted rainfall for the next day, wherein the predicted rainfall for the next day refers to the predicted rainfall for the day after the first predicted rainfall; If the first predicted rainfall amount has a predicted rainfall amount for the day after next, identifying the predicted rainfall amount for the day after next of the first predicted rainfall amount; Respectively update the current soil water storage and the first predicted rainfall using the iterative soil water storage and the predicted rainfall for the next day, and return to the above step of determining whether the first predicted rainfall is 0; If the first predicted rainfall does not include the predicted rainfall for the next day, a soil moisture prediction curve is drawn according to the current soil moisture content and the iterative soil moisture content.

3. The method for optimizing water and fertilizer utilization efficiency of corn fields according to claim 2, characterized in that: The surface runoff formula is as follows: ； in, Indicates the number of curves.

4. The method for optimizing water and fertilizer utilization efficiency of corn fields according to claim 3, characterized in that: The formula for deep leakage is as follows: ； in, represents the unsaturated hydraulic conductivity, Represents the hydraulic gradient.

5. The method for optimizing water and fertilizer utilization efficiency of corn fields according to claim 4, characterized in that: The step of determining the irrigation selection period according to the soil lower limit water content comprises: Determining whether there is only one lower limit soil moisture content in the soil moisture prediction curve; If there is only one soil lower limit moisture content in the soil moisture prediction curve, identifying the soil moisture prediction time point corresponding to the soil lower limit moisture content; If there is more than one soil lower limit moisture content in the soil moisture prediction curve, identifying a first lower limit moisture content in the soil moisture prediction curve, wherein the first lower limit moisture content refers to the first soil lower limit moisture content in the soil moisture prediction curve; Identifying a soil moisture prediction time point corresponding to the first lower limit moisture content; The current time point is obtained, and the irrigation selection period is determined according to the current time point and the soil moisture prediction time point.

6. The method for optimizing water and fertilizer utilization efficiency of corn fields according to claim 5, characterized in that: The step of determining the simulated irrigation parameters according to the irrigation selection period, and performing soil irrigation simulation using the simulated irrigation parameters and the soil moisture prediction curve to obtain a soil moisture simulation curve set includes: A set of simulated irrigation time points is selected according to a preset time interval within the irrigation selection period, and simulated irrigation time points are selected in sequence from the set of simulated irrigation time points. Identify a simulated irrigation date corresponding to the simulated irrigation time point; Identifying the simulated predicted rainfall corresponding to the simulated irrigation date in the current rainfall prediction curve; A simulated irrigation water volume set is obtained, simulated irrigation water volumes are sequentially extracted from the simulated irrigation water volume set, and the first soil water storage formula and the second soil water storage formula are updated using the simulated irrigation water volumes, wherein the updated first soil water storage formula is as follows: ； in, represents the simulated irrigation water volume; The updated second soil water storage formula is as follows: ； Using the simulated predicted rainfall to update the first predicted rainfall, and returning to the above step of determining whether the first predicted rainfall is 0, to obtain a soil moisture simulation curve corresponding to the simulated irrigation parameter; The soil moisture simulation curves corresponding to various simulated irrigation parameters are collected to obtain a soil moisture simulation curve set.

7. The method for optimizing water and fertilizer utilization efficiency of corn fields according to claim 6, characterized in that: The step of selecting a soil moisture target curve from the soil moisture simulation curve set according to a preset soil moisture standard includes: Extracting soil moisture simulation curves in sequence from the soil moisture simulation curve set; Determining the soil intermediate moisture content according to the optimal soil moisture range, wherein the soil intermediate moisture content refers to the median value of the optimal soil moisture range; Constructing a soil moisture middle line segment according to the soil middle moisture content; Determine whether the soil moisture simulation curve and the soil moisture middle line segment have an intersection; If there is no intersection between the soil moisture simulation curve and the soil moisture middle line segment, determining whether the soil moisture simulation curve is located above the soil moisture middle line segment; If the soil moisture simulation curve is above the soil moisture middle line segment, the recommended degree of simulated irrigation parameters is calculated using the following formula: ； in, Indicates the recommended degree of simulated irrigation parameters, represents the first recommendation weight, represents the integral area of ​​the soil moisture simulation curve, represents the integrated area of ​​the middle line segment containing soil moisture; If the soil moisture simulation curve is not located above the soil moisture middle line segment, the recommended degree of simulated irrigation parameters is calculated using the following formula: ； in, represents the second recommendation weight; If there is an intersection between the soil moisture simulation curve and the soil moisture middle line segment, the soil moisture simulation curve and the soil moisture middle line segment are segmented using the intersection to obtain a first time zone line pair and a second time zone line pair; Calculate the recommended degree of simulated irrigation parameters according to the first time zone line pair and the second time zone line pair; The simulated irrigation parameter recommendation degrees corresponding to the various soil moisture simulation curves are collected to obtain a simulated irrigation parameter recommendation degree set, a maximum simulated irrigation parameter recommendation degree is identified in the simulated irrigation parameter recommendation degree set, and a soil moisture target curve corresponding to the maximum simulated irrigation parameter recommendation degree is identified.

8. The method for optimizing water and fertilizer utilization efficiency of corn fields according to claim 7, characterized in that: The step of calculating the recommended degree of simulated irrigation parameters according to the first time zone line pair and the second time zone line pair comprises: Respectively identifying a first target recommendation weight for the first time zone line pair and a second target recommendation weight for the second time zone line pair; Calculating a first absolute area difference and a second absolute area difference of the first time zone line pair and the second time zone line pair respectively; Calculate the first time zone recommendation degree according to the first target recommendation weight and the first area absolute difference, and calculate the second time zone recommendation degree according to the second target recommendation weight and the second area absolute difference; The simulated irrigation parameter recommendation degree is calculated according to the first time zone recommendation degree and the second time zone recommendation degree, wherein the simulated irrigation parameter recommendation degree is the sum of the first time zone recommendation degree and the second time zone recommendation degree.

9. The method for optimizing water and fertilizer utilization efficiency of corn fields according to claim 8, characterized in that: The step of selecting a target fertilization time and a target fertilization amount from the soil moisture target curve according to a preset fertilization standard includes: Obtaining the rainfall prediction duration of the current rainfall prediction curve and the fertilization phase duration of the current fertilization phase; The number of fertilization nodes is calculated according to the duration of the fertilization phase and the rainfall prediction duration using the following formula: ； in, Indicates the number of fertilization nodes, Indicates the floor symbol, Indicates the duration of the fertilization phase, Indicates the duration of rainfall forecast; Obtaining the total amount of fertilizer applied in the current fertilization stage; Calculating a target fertilization amount according to the number of fertilization nodes and the total fertilization amount, wherein the target fertilization amount is equal to the ratio of the total fertilization amount to the number of fertilization nodes; The target fertilization time is equidistantly set within a preset current fertilization period according to the number of fertilization nodes.

10. A water-fertilizer integrated water and fertilizer utilization efficiency optimization system for corn fields, characterized in that: The system comprises: The soil lower limit moisture content judgment module is used to obtain the optimal soil moisture content interval corresponding to the current fertilization stage, and identify the soil lower limit moisture content in the optimal soil moisture content interval; obtain the current rainfall prediction curve, and perform soil moisture prediction according to the current rainfall prediction curve to obtain the soil moisture prediction curve; determine whether the soil moisture prediction curve has the soil lower limit moisture content; if the soil moisture prediction curve does not have the soil lower limit moisture content, return to the above step of obtaining the current rainfall prediction curve; An irrigation parameter determination module is used to determine an irrigation selection period according to the soil lower limit moisture content if the soil moisture prediction curve has a soil lower limit moisture content, wherein the end point of the irrigation selection period is the time point corresponding to the soil lower limit moisture content; determine a simulated irrigation parameter according to the irrigation selection period, perform soil irrigation simulation using the simulated irrigation parameter and the soil moisture prediction curve, and obtain a soil moisture simulation curve set, wherein the simulated irrigation parameter includes: a simulated irrigation time point and a simulated irrigation water volume; select a soil moisture target curve from the soil moisture simulation curve set according to a preset soil moisture standard, and identify a target irrigation time point and a target irrigation water volume corresponding to the soil moisture target curve; A fertilization parameter determination module, used to select a target fertilization time and a target fertilization amount from the soil moisture target curve according to a preset fertilization standard; The integrated fertilization module is used to fertilize the corn field according to the target irrigation time point, target irrigation water volume, target fertilization time and target fertilization volume.

Images