A method for determining crop coefficient, computer equipment and medium

Abstract

The present invention provides a method for determining a crop coefficient, a computer device and a medium, which belongs to the field of agricultural technology. The method comprises: obtaining a reference crop evapotranspiration value by acquiring meteorological data of farmland, dynamically monitoring the crop runoff rate and the volumetric water content of farmland soil by using intelligent equipment, and obtaining crop transpiration according to the crop runoff rate; obtaining soil evaporation according to the volumetric water content of farmland soil and meteorological data; calculating the crop transpiration and soil evaporation with the reference crop evapotranspiration value, respectively, to obtain a transpiration crop coefficient and a transpiration crop coefficient; and obtaining a crop coefficient according to the sum of the transpiration crop coefficient and the transpiration crop coefficient. The crop coefficient is combined with the reference crop evapotranspiration to improve the utilization efficiency of water in agriculture, which is conducive to adjusting the irrigation amount and formulating a reasonable irrigation plan.

Description

Technical Field

[0001] The invention belongs to the field of agriculture, and in particular relates to a method for determining a crop coefficient, a computer device and a medium. Background Art

[0002] Water management in the crop production process is crucial to the sustainable development of agriculture. With the diversification of agricultural planting patterns, achieving efficient use of water resources while ensuring high crop yields has become one of the important research directions of agricultural water management. Water in farmland is mainly consumed through crop transpiration and evaporation from the soil surface. Transpiration is the process of plants releasing water through leaf stomata, which is closely related to the growth status and environmental conditions of crops; while soil evaporation is affected by factors such as precipitation, irrigation, sunshine and air humidity. The water balance of farmland involves the interaction of soil moisture, precipitation, irrigation and crop evaporation. In modern agriculture, the rational formulation of irrigation plans needs to take into account the transpiration of crops, evaporation of soil and the impact of meteorological conditions on water demand.

[0003] In agricultural water resource management, the crop coefficient (Kc) reflects the changes in the water demand of specific crops in different growth periods, and is suitable for adjusting irrigation volume and formulating reasonable irrigation plans. Existing Kc values ​​are usually based on empirical data under standard conditions or regional test results, and are given by stage during the growth cycle. The actual transpiration and evaporation of crops are significantly affected by the dynamic changes in meteorological conditions, and the Kc values ​​obtained by traditional methods cannot reflect these changes. Moreover, the calculation of traditional Kc values ​​mostly relies on historical data and estimates, rather than real-time monitoring of crop and soil moisture data. As climate volatility intensifies, the actual water demand cannot be accurately predicted based on average empirical values ​​alone, the Kc value cannot be flexibly adjusted accordingly, and water resources cannot be analyzed and utilized according to actual conditions. Summary of the invention

[0004] In order to solve the problem that the crop coefficient cannot be dynamically adjusted according to the environment and real-time farmland data, the present invention provides a method for determining the crop coefficient, a computer device and a medium.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A method for determining a crop coefficient comprises the following steps:

[0007] Calculate reference crop evapotranspiration values ​​based on daily maximum temperature, daily minimum temperature, relative humidity, precipitation, atmospheric pressure, and sunshine hours of farmland;

[0008] Obtaining the volumetric water content of farmland soil, and calculating the change in the moisture depth of the root layer soil according to the volumetric water content of the farmland soil; monitoring the crop runoff rate, and calculating the crop transpiration according to the runoff rate;

[0009] Calculating soil evaporation through a water balance equation based on the change in the root layer soil moisture depth, farmland precipitation, irrigation water, and crop transpiration;

[0010] The transpiration crop coefficient is calculated according to the reference crop evapotranspiration value and the crop transpiration amount; the evaporation coefficient is calculated according to the reference crop evapotranspiration value and the soil evaporation amount; and the crop coefficient is obtained according to the sum of the transpiration crop coefficient and the evaporation coefficient.

[0011] Preferably, the soil evaporation is calculated according to the water balance equation, specifically:

[0012] E=D+P+I-Tr;

[0013] Among them, E is soil evaporation; D is the change in soil moisture depth in the root layer; P is farmland precipitation; I is the irrigation amount; Tr is crop transpiration.

[0014] Preferably, the calculation formula for the crop transpiration is:

[0015] Tr=Vs*3.14*R 2 *ppd*24*10 -3 ;

[0016] Where R is the crop stem radius; ppd is the crop planting density; Vs is the crop runoff rate.

[0017] Preferably, the calculation formula of the transpiration crop coefficient is specifically:

[0018] K Tr =ET0 / Tr;

[0019] Among them, Tr is crop evapotranspiration; ET0 is the reference crop evapotranspiration value.

[0020] Preferably, the calculation formula of the evaporation coefficient is specifically:

[0021] Ke=ET0 / E;

[0022] Where, E is soil evaporation; ET0 is the reference crop evapotranspiration value.

[0023] Preferably, the monitoring of crop runoff rate comprises installing a stem flow meter at the base of the crop stem to monitor the crop runoff rate.

[0024] The present invention also provides a computer device, comprising a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps described in the method for determining a crop coefficient.

[0025] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is loaded by a processor, the steps described in the method for determining a crop coefficient can be executed.

[0026] The method for determining a crop coefficient provided by the present invention has the following beneficial effects:

[0027] The present invention obtains reference crop evapotranspiration values ​​by acquiring meteorological data of farmland, dynamically monitors crop runoff rate and farmland soil volume water content, and performs calculations based on dynamically changing data, thereby overcoming the static deficiency of the traditional Kc value, obtaining crop transpiration based on crop runoff rate; obtaining soil evaporation based on farmland soil volume water content and meteorological data, realizing dynamic calculation of soil evaporation, and solving the defect that transpiration and evaporation cannot be decoupled in traditional crop coefficient calculation. Crop transpiration and soil evaporation are calculated with reference crop evapotranspiration values ​​respectively to obtain transpiration crop coefficients and transpiration crop coefficients, and the crop coefficients can be dynamically adjusted to adapt to environmental changes according to meteorological conditions and different growth stages of crops. The crop coefficient is combined with the reference crop evapotranspiration, which is conducive to subsequent adjustment of irrigation volume and formulation of irrigation plans. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiment of the present invention and its design scheme, the following briefly introduces the drawings required for this embodiment. The drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 The present invention is a flowchart of a method for determining a crop coefficient according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the technical solution of the present invention and implement it, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the scope of protection of the present invention.

[0031] Example

[0032] The present invention provides a method for determining a crop coefficient, such as Figure 1 As shown, the specific steps include:

[0033] S1. Use the meteorological station to monitor the daily maximum temperature (Tmax, ℃), daily minimum temperature (Tmin, ℃), relative humidity (RH, %), precipitation (P, mm), atmospheric pressure (p, KPa) and sunshine hours (n, h) of the farmland.

[0034] S2. Use a stem flow meter to monitor the stem flow rate of crops (Vs, cm h1). The stem flow meter is installed at the base of the crop stem.

[0035] S3. Use soil moisture sensors to monitor the volumetric moisture content of farmland soil (θv,%). Calculate the change in the depth of the root layer soil moisture (D, mm) using the following formula:

[0036] D = θv*Z;

[0037] Where Z is the soil thickness at the root layer;

[0038] S4, crop transpiration (Tr, mm) is calculated from the crop stem flow rate in S2. The calculation formula is as follows:

[0039] Tr=Vs*3.14*R 2 *ppd*24*10 -3 ;

[0040] Where R is the crop stem radius, ppd is the crop planting density, and Vs is the stem flow rate.

[0041] S5. Calculate soil evaporation (E, mm) using the water balance equation. The calculation formula is as follows:

[0042] E=D+P+I-Tr;

[0043] Among them, E is soil evaporation; D is the change in soil moisture depth in the root layer; P is farmland precipitation; I is the irrigation amount; Tr is crop transpiration.

[0044] S6. The reference crop evapotranspiration (ET0, mm) is calculated using the Penman formula based on the meteorological data observed in S1.

[0045] S7, transpiration crop coefficient (Kc Tr ) is obtained from the reference crop evapotranspiration (ET0) calculated by S6 and the crop transpiration (Tr, mm) calculated by S4, and the calculation formula is as follows:

[0046] K Tr =ET0 / Tr;

[0047] Among them, Tr is crop evapotranspiration; ET0 is the reference crop evapotranspiration value.

[0048] S8, evaporation coefficient (Ke) is obtained by the reference crop evapotranspiration (ET0) calculated by S6 and the soil evaporation (E, mm) calculated by S5, and the calculation formula is as follows:

[0049] Ke=ET0 / E;

[0050] Where, E is soil evaporation; ET0 is the reference crop evapotranspiration value.

[0051] S9, the crop coefficient Kc is obtained by the transpiration crop coefficient (KcTr) calculated in step 7 and the evaporation coefficient (Ke) calculated in step 8. The calculation formula is: Kc=Kc Tr +Ke.

[0052] The present invention has the following beneficial effects: (1) The traditional Kc value adopts a fixed or staged empirical value, which is difficult to adapt to the dynamic changes of climate and crop growth. The present invention dynamically calculates the transpiration coefficient (Kc) by real-time monitoring of crop transpiration (Tr) and soil evaporation (E). Tr ) and evaporation coefficient (Ke), thereby obtaining a more accurate Kc value and improving the scientific nature of irrigation management. (2) The crop transpiration and soil evaporation are monitored and calculated separately, which effectively solves the problem that the traditional Kc calculation cannot accurately distinguish between the two. This improvement helps the irrigation system to better respond to different environmental and soil conditions and ensure the effective use of water. (3) The traditional Kc model has poor applicability in multi-crop planting environments. The present invention can cope with a variety of planting patterns, especially in complex planting systems, by independently calculating the water requirements of different crops to achieve precise irrigation. (4) By integrating weather stations, stem flow meters, soil moisture sensors and other equipment, the present invention realizes real-time data collection and analysis, supports the irrigation system to automatically adjust the irrigation plan according to the current weather and crop conditions, and improves the response speed and intelligence level of the system.

[0053] At the same time, the present invention is applicable to a variety of agricultural planting systems, especially in complex planting systems, and can accurately monitor and manage the water requirements of different crops. By separating transpiration and evaporation, the present invention overcomes the shortcomings of traditional crop coefficient calculations that cannot cope with multi-crop systems, and has strong practicality and flexibility. It can be used for: Monocropping agriculture: suitable for irrigation management in precision agriculture, helping farmers make scientific decisions based on real-time data; intercropping system: particularly suitable for mixed planting of multiple crops, by independently monitoring the transpiration rate of each crop, and reasonably allocating irrigation water; drought and rain-fed agriculture: by dynamically adjusting the irrigation amount, limited water resources can be reasonably allocated under drought conditions.

[0054] The present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps in an embodiment of a method for determining a crop coefficient. The specific implementation method can be found in the method embodiment, which will not be described in detail here.

[0055] Furthermore, the present invention also provides a non-temporary computer-readable storage medium containing instructions, and a computer program is stored on the storage medium. For example, a memory containing instructions, the above instructions can be executed by a processor of a computer device to complete the above method. For example, the non-temporary computer-readable storage medium can be a ROM, a random access memory (RAM), a CD-ROM, a tape, a floppy disk, and an optical data storage device. When the computer program is executed by the processor, the steps in an embodiment of a method for determining a crop coefficient can be implemented. The specific implementation method can be referred to the method embodiment, which will not be repeated here.

[0056] It should be understood by those skilled in the art that embodiments of the present invention may provide methods, systems or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware aspects. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0057] The present invention is described with reference to flowcharts and / or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as a combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0058] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0059] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1The steps for the functions specified in one or more boxes.

[0060] It should be pointed out that the specific implementation methods described above can enable those skilled in the art to understand the invention more comprehensively, but do not limit the invention in any way. Therefore, although the invention has been described in detail in this specification and embodiments, those skilled in the art should understand that the invention can still be modified or replaced by equivalents; and all technical solutions and improvements that do not deviate from the spirit and scope of the invention are included in the protection scope of the patent for the invention. Any figure mark in the claims should not be regarded as limiting the claims involved. Any simple change or equivalent replacement of the technical solution that can be obviously obtained by any technician familiar with the field within the technical scope disclosed in the present invention belongs to the protection scope of the present invention.

Claims

1. A method for determining a crop coefficient, characterized in that: The following steps are involved: Calculate reference crop evapotranspiration values ​​based on daily maximum temperature, daily minimum temperature, relative humidity, precipitation, atmospheric pressure, and sunshine hours of farmland; Obtain the volumetric water content of farmland soil, and calculate the change in the moisture depth of the root layer soil according to the volumetric water content of the farmland soil; monitor the crop runoff rate, and calculate the crop transpiration according to the runoff rate. The specific calculation formula of the crop transpiration is: Tr = Vs*3.14*R 2 *ppd*24*10 -3 , where R is the crop stem radius; ppd is the crop planting density; Vs is the crop runoff rate; Calculating soil evaporation through a water balance equation based on the change in the root layer soil moisture depth, farmland precipitation, irrigation water, and crop transpiration; The transpiration crop coefficient is calculated according to the reference crop evapotranspiration value and the crop transpiration amount; the evaporation coefficient is calculated according to the reference crop evapotranspiration value and the soil evaporation amount; and the crop coefficient is obtained according to the sum of the transpiration crop coefficient and the evaporation coefficient.

2. A method for determining a crop coefficient according to claim 1, characterized in that: The soil evaporation is calculated by the water balance equation, specifically: E=D+P+I-Tr; Among them, E is soil evaporation; D is the change in soil moisture depth in the root layer; P is farmland precipitation; I is the irrigation amount; Tr is crop transpiration.

3. A method for determining a crop coefficient according to claim 1, characterized in that: The calculation formula of the transpiration crop coefficient is specifically: Kc Tr =ET0 / Tr; Among them, Tr is crop evapotranspiration; ET0 is the reference crop evapotranspiration value.

4. A method for determining a crop coefficient according to claim 1, characterized in that: The calculation formula of the evaporation coefficient is specifically: Ke=ET0 / E; Where, E is soil evaporation; ET0 is the reference crop evapotranspiration value.

5. A method for determining a crop coefficient according to claim 1, characterized in that: The monitoring of crop runoff rate specifically involves installing a stem flow meter at the base of a crop stem to monitor the crop runoff rate.

6. A computer device comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to any one of claims 1 to 5.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is loaded into a processor, it can execute the steps of the method according to any one of claims 1 to 5.

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