Irrigation area water management method and system based on digital twinning

Abstract

The invention relates to the technical field of intelligent agriculture, in particular to a digital twinborn-based irrigation area water management method and system. The digital twinning-based irrigation area water management method comprises the following steps: detecting and obtaining irrigation area soil moisture content data, and constructing soil moisture content curved surfaces of different soil depths according to the soil moisture content data; acquiring crop planting information of each irrigation area unit in the irrigation area, and constructing a crop soil moisture content curve according to the crop information. And according to the weather data in the prediction period, obtaining each coordinate point and a soil depth prediction soil moisture content curve of the irrigation area in the prediction period. Calculating a soil moisture content difference value corresponding to each coordinate point and depth, and constructing a soil moisture content difference value curve. Whether the soil moisture content difference value of the soil moisture content difference value curve is larger than a preset stage standard soil moisture content difference value or not is judged; and if so, sending an alarm signal. The soil moisture content is predicted according to the weather forecast condition, water consumption of an irrigation area is managed in a targeted mode, crop growth can be intervened, and water resources can be effectively utilized.

Description

Technical Field

[0001] The present invention relates to the field of smart agricultural technology, and in particular to an irrigation area water management method and system based on digital twins. Background Art

[0002] Digital twin is a new type of information technology application that combines objects or systems in the real world with the virtual world to form a digital mirror of an entity. Through digital twin technology, the operation status of the physical world can be simulated, tracked and managed in real time, providing strong support for optimizing production processes, improving equipment performance, predicting faults and other issues. The main application scenarios of digital twin include industrial manufacturing, architectural design, medical health, aerospace, transportation and other fields. For example, in the field of industrial manufacturing, through the digital twin of production lines and equipment, key parameters in the production process can be monitored in real time, abnormal conditions can be found, and adjustments can be made in time, thereby improving production efficiency and product quality. The realization of digital twin technology depends on the development of technologies such as big data, cloud computing, the Internet of Things, and artificial intelligence. Among them, the Internet of Things provides a large amount of sensor data for digital twins, making the digital twin model more accurate; and artificial intelligence can automatically optimize the digital twin model through machine learning algorithms. In short, digital twin technology is an important development direction of the new generation of information technology, which will have a profound impact on all walks of life and promote the digital transformation of traditional industries.

[0003] Irrigation in irrigation areas refers to the introduction of water into farmland to meet the water demand for crop growth. This is a very important agricultural production method that can effectively utilize water resources and improve the yield and quality of crops. In irrigation in irrigation areas, many factors need to be considered, such as soil type, climatic conditions, crop water requirements, etc. In addition, it is necessary to select appropriate irrigation technologies, such as sprinkler irrigation, drip irrigation, pipeline water delivery, etc. In order to ensure the effect of irrigation in irrigation areas, it is also necessary to formulate a reasonable irrigation plan and adjust it according to actual conditions. At the same time, it is also necessary to strengthen the management of water resources, and rationally utilize and protect water resources to ensure the sustainability of irrigation in irrigation areas.

[0004] Existing agricultural irrigation is mainly based on the experience of producers, and general irrigation of crops is implemented, which easily leads to waste of water resources and cannot be optimized. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides an irrigation area water management method based on digital twins, which is used to manage the irrigation water in the irrigation area and realize rational water irrigation. The irrigation area water management method based on digital twins may include the following steps: S1. Detect and obtain the soil moisture data of the irrigation area, and construct a soil moisture surface of different soil depths based on the soil moisture data. The soil moisture surface is constructed based on digital twins, and it is necessary to detect the soil moisture data of the irrigation area in real time. The irrigation area is the land in the area that needs to be monitored and managed. Generally, the irrigation area is an arid or semi-arid land area, or the crops planted require frequent or strict water requirements. Crops in these areas cannot rely entirely on rainfall. When the soil moisture value needs to be increased, the land where the crops are located can be irrigated in time. This requires pre-laying irrigation pipes on the land in the irrigation area. The spraying area of ​​the irrigation pipe needs to be able to completely cover the land area of ​​the entire irrigation area, and evenly irrigate all the land in the irrigation area. The soil moisture data of the irrigation area can be detected by the soil moisture detection module on the irrigation area land to obtain the soil moisture data of the irrigation area.

[0006] S2. Obtain information on crops planted in each irrigation unit in the irrigation area, and construct a crop soil moisture curve based on the crop information. It can be learned from the above irrigation unit information that the crops planted in each irrigation unit are of the same type. In actual planting operations, the land is also divided into units, so this method is closer to the actual planting situation. The crop information may include the type of crops planted, the growth stage of the crops, and the soil moisture data required for each growth stage of the crops.

[0007] S3. According to the weather data within the forecast period, the soil moisture curve of each coordinate point and soil depth forecast in the irrigation area within the forecast period is obtained. The forecast period is the length of time we can predict the future weather, which is generally 5-15 days. This can ensure water management, improve the effective use of water resources, avoid unnecessary waste of water resources, and better meet the needs of crop growth.

[0008] S4. Compare the predicted soil moisture curve with the crop soil moisture curve, calculate the soil moisture difference ΔC corresponding to each coordinate point and depth, and construct a soil moisture difference curve. The soil moisture difference ΔC=C'-C, where C' is the soil moisture value corresponding to the crop soil moisture curve, C is the soil moisture value corresponding to the predicted soil moisture curve, and the horizontal coordinate of the soil moisture difference curve is the period unit within the prediction period, and the vertical coordinate is the soil moisture value.

[0009] S5. Determine whether the soil moisture difference ΔC of the soil moisture difference curve is greater than a preset stage standard soil moisture difference ΔC 标 If yes, an alarm signal is sent, if no, no alarm signal is sent. Stage standard soil moisture difference ΔC 标 This value will change according to the growth stage of the crop and the different soil depth changes. For the same crop, the soil moisture values ​​required at different growth stages are different. 标This value changes according to the growth stage of the crop.

[0010] Preferably, the alarm signal sent may include the corresponding coordinate range, the soil moisture difference ΔC equal to the stage standard soil moisture difference ΔC 标 The corresponding time point and soil depth as well as the soil moisture difference ΔC can be used to obtain the irrigation area unit that needs irrigation and the corresponding time, which is convenient for later water management.

[0011] Preferably: the irrigation area water management method based on digital twins also includes: S6. Irrigate the irrigation area according to the alarm signal.

[0012] Preferably, the unit water consumption of irrigation can be calculated by the soil depth and the soil moisture difference ΔC. The specific unit water consumption of irrigation is the irrigation amount per unit area, which can be determined by the irrigation water depth and can be: , where ρ 土 is the soil density under the current average soil moisture, ρ 水 is the density of water, h 2 is the effective depth of soil evaluation, a is the soil property coefficient, and h is the evaluation depth of the land in the irrigation area. The time point of irrigation can be determined according to the corresponding soil depth, which can be obtained based on experience and will not be elaborated here.

[0013] Preferably, the specific method for obtaining the soil moisture surface may include: constructing a plane coordinate system, which covers the land area of ​​the irrigation area. The soil moisture data of the irrigation area mainly includes the installation coordinates (x i ,y i , z i ) and the detection value C i , where i is the number of the soil moisture detection module. (x i ,y i ) is the plane coordinate of the soil moisture detection module numbered i, z i is the buried depth of the soil moisture detection module numbered i, and the detection value C i Detect the value of the soil moisture detection module numbered i. Calculate the soil moisture value C, and then implant the soil moisture values ​​of each soil depth layer into the plane coordinate system to obtain the soil moisture surface.

[0014] Preferred: Moisture content value , where k and j are the numbers of the coordinate points in the same soil depth coordinate system, j≠k, initially j and k can be the numbers of the soil moisture detection module, (x j ,y j ), (x k ,y k) is the plane coordinate of the soil moisture detection module numbered j or k, z j 、z k is the buried depth of the soil moisture detection module numbered j or k, C j , C k Detect the value for the soil moisture detection module numbered j or k.

[0015] Preferably: the method for constructing a crop soil moisture curve includes constructing a plane coordinate system, the horizontal coordinate of the plane coordinate system is the time point of the crop growth stage, and the vertical coordinate can be the soil moisture value of each soil depth layer. The corresponding time point according to the minimum soil moisture value corresponding to each soil depth required for crop growth is implanted into the coordinate system, and then each point is connected according to time, so that the crop soil moisture curve can be obtained.

[0016] Preferably, weather data may include surface temperature and rainfall, etc. The values ​​of surface temperature and rainfall can be obtained by searching the local meteorological bureau to obtain the weekly weather forecast, etc.

[0017] Preferably, the method for constructing the predicted soil moisture curve may include: constructing a plane coordinate system, the horizontal coordinate is each period unit in the prediction period, the vertical coordinate is the soil moisture value, and calculating the predicted soil moisture value C of each coordinate point in the prediction period. n , and then the predicted soil moisture value C n The periodic units are implanted into the coordinate system and connected in sequence to form the predicted soil moisture curve.

[0018] Preferred: Predicted soil moisture value at each coordinate point , where n is the period unit number within the prediction period, C n is the predicted soil moisture value of the nth period unit, n=1, 2, ...; C 0 is the soil moisture value currently detected, ρ 土 is the soil density under the current average soil moisture, ρ 水 is the density of water, h 2 h is the effective depth of soil evaluation, and its specific value is generally 2-5m, of course, it does not exclude the setting of other values; 1 is the rainfall in the period unit numbered n. a is the soil property coefficient, and its value is generally 1-10. h is the evaluation depth of the land in the irrigation area, which can be the burial depth of the corresponding soil moisture detection module, and h≤h 2 , E is the unit surface evaporation.

[0019] Preferred: Evaporation per unit surface , where ε is the evaporation effectiveness coefficient. The heat absorbed by the soil can be dissipated through evaporation and thermal radiation. The evaporation effectiveness coefficient value is related to the soil moisture retention, air flow and humidity. It can be obtained by looking up a table or experience. Its value is generally 0.1-0.8. b is the temperature influence index of the soil. Its value can be obtained through temperature experiments. Its value is generally between 1-10. The specific details are not repeated here. T 1 is the evaluation standard temperature, T M is the effective surface temperature.

[0020] Preferred: Effective surface temperature , where T max It can be the maximum surface temperature within this period unit.

[0021] Preferably: the calculation method of unit surface evaporation E may also include: constructing a plane coordinate system, the horizontal coordinate is each time point t in the period unit, for example, the period unit is one day, the time point t can be each hour within a day, the vertical coordinate is the surface temperature, the surface temperature value T corresponding to each time point is obtained according to the weather conditions, and then the surface temperature value is implanted into the plane coordinate system according to the time point, and then connected in chronological order, so as to form a surface temperature curve. Integrate the surface temperature curve to obtain the unit surface evaporation , where T is the value of the vertical coordinate of the surface temperature curve, t is the time value of the horizontal coordinate, C 1 is the starting point of the forecast cycle unit. When the forecast cycle unit is one day, C 1 It can be the time when the surface temperature drops to the average temperature at night, C 2 The end point of the prediction cycle unit can be the time point when the surface temperature rises to the average night temperature. 0 In order to reduce the unit evaporation to the average night temperature, this value can be considered as a fixed value. The specific value depends on the surface soil characteristics and temperature. The value is generally 0.001-0.1.

[0022] The present invention also proposes an irrigation area water management system based on digital twin, comprising: The soil moisture detection module is buried in different soil depths in the irrigation area to detect and obtain soil moisture data in the irrigation area. The required soil moisture detection modules are pre-buried in each irrigation unit according to the detection depth. These soil moisture detection modules are installed at different depths, and the depth setting needs to be determined according to the root distribution of the crops.

[0023] The crop information acquisition module is used to obtain the crop planting information of each irrigation unit in the irrigation area. The crops planted in each irrigation unit are the same type of crops. In actual planting operations, the land is also divided into units, so this method is closer to the actual planting situation. The crop information may include the type of crops planted, the growth stage of the crops, and the soil moisture data required for each growth stage of the crops.

[0024] The weather information acquisition module is used to obtain weather data within the forecast period. The forecast period is the length of time we can predict future weather, and the forecast period is generally 5-15 days. Weather data may include surface temperature and rainfall, etc. The values ​​of surface temperature and rainfall can be obtained by looking up the local meteorological bureau to obtain the weekly weather forecast, etc.

[0025] The analysis and construction module is used to construct a crop moisture curve based on crop information; based on the moisture data, a soil moisture surface of different soil depths and a predicted moisture curve of each coordinate point and soil depth in the irrigation area within the prediction period are constructed. This can ensure water management, improve the effective use of water resources, avoid unnecessary waste of water resources, and better meet the needs of crop growth. The predicted moisture curve is compared with the crop moisture curve, and the moisture difference ΔC corresponding to each coordinate point and depth is calculated, and a moisture difference curve is constructed. The moisture difference ΔC=C'-C, wherein C' is the moisture value corresponding to the crop moisture curve, C is the moisture value corresponding to the predicted moisture curve, the horizontal coordinate of the moisture difference curve is the period unit within the prediction period, and the vertical coordinate is the moisture value.

[0026] The analysis and judgment module is used to judge whether the soil moisture difference ΔC of the soil moisture difference curve is greater than a preset stage standard soil moisture difference ΔC 标 If yes, an alarm signal is sent, if no, no alarm signal is sent. Stage standard soil moisture difference ΔC 标 This value will change according to the growth stage of the crop and the different soil depth changes. For the same crop, the soil moisture values ​​required at different growth stages are different. 标 This value changes according to the growth stage of the crop.

[0027] An irrigation control module is used to irrigate the irrigation area according to the alarm signal; Irrigation water consumption , where ρ 土 is the soil density under the current average soil moisture, ρ 水 is the density of water, h 2is the effective depth of soil evaluation, a is the soil property coefficient, and h is the evaluation depth of the land in the irrigation area. The time point of irrigation can be determined according to the corresponding soil depth and soil penetration time.

[0028] The technical effects and advantages of the present invention are as follows: the management method proposed by the present invention can manage the water use in the irrigation area, intervene in the growth of crops, effectively utilize water resources, and avoid the impact of lack of water on the yield of crops, thus achieving effective control, and can irrigate the irrigation area coordinates in a targeted manner, thus avoiding the waste of water resources and growth interference caused by excessive soil moisture. The utilization rate of water resources and the reasonable allocation and utilization are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a flow chart of an irrigation district water management method based on digital twin proposed in the present invention.

[0030] Figure 2 This is a flow chart of constructing a soil moisture surface in an irrigation area water management method based on digital twins proposed in the present invention.

[0031] Figure 3 This is a flow chart for constructing a crop soil moisture curve in an irrigation area water management method based on digital twins proposed in the present invention.

[0032] Figure 4 This is a flow chart for constructing a soil moisture curve prediction method in an irrigation area water management method based on digital twins proposed in the present invention.

[0033] Figure 5 This is a structural schematic diagram of an irrigation area water management system based on digital twin proposed in the present invention. DETAILED DESCRIPTION

[0034] Embodiments of the present disclosure are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present disclosure, and are not to be construed as limitations of the present disclosure. On the contrary, the embodiments of the present disclosure include all changes, modifications, and equivalents that fall within the spirit and connotation of the appended claims.

[0035] Example 1 Reference Figure 1 In this embodiment, a method for managing irrigation water in an irrigation area based on digital twins is proposed to manage irrigation water in an irrigation area and realize rational water use. The method for managing irrigation water in an irrigation area based on digital twins may include the following steps: S1. Detect and obtain the soil moisture data of the irrigation area, and construct a soil moisture surface of different soil depths based on the soil moisture data. The soil moisture surface is constructed based on digital twins, and it is necessary to detect the soil moisture data of the irrigation area in real time. The irrigation area is the land in the area that needs to be monitored and managed. Generally, the irrigation area is an arid or semi-arid land area, or the crops planted require frequent or strict water requirements. The crops in these areas cannot rely entirely on rainfall. When the crops need to supplement the soil moisture values, the land where the crops are located can be irrigated in time. This requires pre-laying irrigation pipes on the land in the irrigation area. The spraying area of ​​the irrigation pipes needs to be able to completely cover the land area of ​​the entire irrigation area and evenly irrigate all the land in the irrigation area. The laying of pipes is an existing technology, and the details will not be repeated here. The soil moisture data of the irrigation area can be obtained by detecting the irrigation area land through the soil moisture detection module. Reference Figure 2 , the specific method of obtaining the soil moisture data of the irrigation area may include: the irrigation area may be pre-divided into several irrigation area units. The specific division method of the irrigation area units may be determined according to the area and distribution environment of the irrigation area land, the effective coverage area of ​​the soil moisture detection module and the types of crops planted. The details will not be elaborated here. The required soil moisture detection modules are pre-buried in each irrigation area unit according to the detection depth. These soil moisture detection modules are installed at different depths. The depth setting needs to be determined according to the root distribution of the crops. The details will not be elaborated here. Then construct a plane coordinate system, which covers the area of ​​the irrigation area land. The burial depth and coordinate position of the soil moisture detection module can be determined according to the actual situation. Generally, it is installed in the most representative position and cannot be installed at the edge, corner and other positions of the irrigation area unit. The soil moisture data of the irrigation area mainly includes the installation coordinates (x i ,y i , z i ) and the detection value C i , where i is the number of the soil moisture detection module. (x i ,y i ) is the plane coordinate of the soil moisture detection module numbered i, z i is the buried depth of the soil moisture detection module numbered i, and the detection value C i Detect the value for the soil moisture detection module numbered i. The soil moisture data of each point is not a soil moisture surface. The construction method of the soil moisture surface can directly diffuse and cover the data. Of course, it can also analyze and calculate the soil moisture values ​​at the same depth. The specific soil moisture values , where k and j are the numbers of the coordinate points in the same soil depth coordinate system, j≠k, and at the beginning j and k can be the numbers of the soil moisture detection module, and then the calculation is performed to obtain the soil moisture values ​​of each point in the coordinate system, and then the calculation is performed in a loop to obtain the soil moisture values ​​corresponding to each coordinate in the coordinate system, and then the soil moisture values ​​of each soil depth layer are implanted into a plane coordinate system to obtain the soil moisture surface. The soil moisture values ​​calculated by this method are evenly distributed, there is no large soil moisture gradient, which is in line with the actual situation and can fully reflect the soil moisture distribution.

[0036] S2. Obtain information on crops planted in each irrigation unit in the irrigation area, and construct a crop soil moisture curve based on the crop information. It can be learned from the above irrigation unit information that the crops planted in each irrigation unit are the same type of crops. In actual planting operations, the land is also divided into units, so this method is closer to the actual planting situation. The crop information may include the type of crops planted, the growth stage of planting, and the soil moisture data required for each growth stage of the crops. For example, corn is planted in an irrigation unit, and the growth stages of corn include sowing, emergence, jointing, earing, grains, etc. Of course, this is a simple distinction. The best way to distinguish is that the growth cycle of corn is 100-120 days. Specifically, it can be divided according to days, and the best soil moisture data for corn can be obtained every day or every week based on experience or experiments. It is specifically a prior art, not the subject of protection of this application, and will not be elaborated here. Reference Figure 3 , construct a plane coordinate system, the horizontal coordinate of the plane coordinate system is the time point of the growth stage of the crop, and the vertical coordinate can be the soil moisture value of each soil depth layer, which can be covered for each depth of soil moisture value, so that the soil moisture value corresponding to each depth can be implanted into the coordinate system according to the corresponding time point, and then the points are connected according to time, so that the crop moisture curve can be obtained. The moisture value suitable for crop growth should be a range. In order to facilitate analysis, the crop moisture curve selected here is the optimal lower limit curve, that is, above this moisture curve, crops can grow optimally and will not affect the yield due to moisture reasons. The crop moisture curve obtained by this method can clearly display the moisture value of each soil depth layer, and the display is clearer. In order to display more clearly and not easy to confuse, the vertical coordinate can also be divided and accumulated for display, which will not be described in detail here.

[0037] S3. According to the weather data within the prediction period, the soil moisture curves of each coordinate point and soil depth in the irrigation area within the prediction period are obtained. The prediction period is the length of time we can predict the future weather. Generally, it is based on the current weather forecast data or the soil moisture requirements of crops. In theory, the longer the prediction period, the better, so that the water use management of crops can be more flexible, but the difficulty of prediction will be greater, and the data will be inaccurate. The shorter the prediction period, the smaller the difficulty of prediction, and the more accurate the calculated data will be. However, if the prediction period is too short, water use cannot be effectively managed organically. The prediction period is generally 5-15 days, which can ensure water use management, improve the effective use of water resources, avoid unnecessary waste of water resources, and better meet the needs of crop growth. Weather data can include surface temperature and rainfall, etc. The values ​​of surface temperature and rainfall can be obtained by looking up the local meteorological bureau's weekly weather forecast, etc., which will not be described in detail here. Then, these data are used to construct the soil moisture curve of the irrigation area unit within the prediction period. Reference Figure 4 , which can specifically include calculating the predicted soil moisture value of each coordinate point , where n is the period unit number in the forecast period. In general, in order to facilitate calculation, we can divide the forecast period in advance and define a period unit as 1 day. Of course, other settings are not excluded. C n is the predicted soil moisture value of the nth period unit, n=1, 2, …, N; C 0 is the soil moisture value currently detected, ρ 土 is the soil density under the current average soil moisture, ρ 水 is the density of water, h 2 h is the effective depth of soil evaluation, and its specific value is generally 2-5m, of course, it does not exclude the setting of other values; 1 is the rainfall in the period unit numbered n. a is the soil property coefficient, and its value is generally 1-10. h is the evaluation depth of the land in the irrigation area, which can be the burial depth of the corresponding soil moisture detection module, and h≤h 2 , E is the unit surface evaporation. The soil moisture data calculated by this method can take into account various influencing factors, and the factors are comprehensive. It can be comprehensively evaluated according to different depths and soil properties through factors such as current soil moisture value and rainfall. This evaluation method conforms to the situation that the greater the depth, the greater the difficulty of evaporation. The analysis is accurate and in line with reality. Moreover, this superposition calculation has accurate results and can reflect the changes in cumulative data. The unit surface evaporation E is the evaporation of water that needs to be evaporated through the surface temperature. Its specific value can be calculated according to the surface temperature. The unit surface evaporation can be , where ε is the evaporation effectiveness coefficient. The heat absorbed by the soil can be dissipated through evaporation and thermal radiation. The evaporation effectiveness coefficient value is related to the soil moisture retention, air flow and humidity. It can be obtained by looking up a table or experience. Its value is generally 0.1-0.8. b is the temperature influence index of the soil. Its value can be obtained through temperature experiments. Its value is generally between 1-10. The specific details are not repeated here. T 1 is the evaluation standard temperature, T M The effective surface temperature can be calculated based on the surface temperature of the weather forecast, and the details are not described here. , where T max It can be the maximum surface temperature in this period unit, T 1 and T M It can be absolute temperature in K. In theory, T 1 The value can be 273K. Of course, this is a theoretical value and does not exclude the setting of other values. This calculation method is an estimate of the effective surface temperature, and there will be certain errors. The calculation method of the unit surface evaporation E can also include: constructing a plane coordinate system, the horizontal coordinate is each time point t in the period unit, for example, the period unit is one day, the time point t can be every hour within a day, the vertical coordinate is the surface temperature, and the surface temperature value T corresponding to each time point is obtained through weather conditions, and then the surface temperature value is implanted into the plane coordinate system according to the time point, and then connected in chronological order, so as to form a surface temperature curve. Integrate the surface temperature curve to obtain the unit surface evaporation , where T is the value of the vertical coordinate of the surface temperature curve, t is the time value of the horizontal coordinate, C 1 is the starting point of the forecast cycle unit. When the forecast cycle unit is one day, C 1 It can be the time when the surface temperature drops to the average temperature at night, C 2 The end point of the prediction cycle unit can be the time point when the surface temperature rises to the average night temperature. 0 In order to reduce the unit evaporation to the average night temperature, this value can be considered as a fixed value. The specific value depends on the surface soil characteristics and temperature. The value is generally 0.001-0.1. The specific details are not elaborated here. This method can be used to calculate the relationship between surface evaporation and temperature, which reflects that the higher the temperature, the exponential growth of evaporation, which is more in line with the actual situation of water evaporation.

[0038] S4. Compare the predicted soil moisture curve with the crop soil moisture curve, calculate the soil moisture difference ΔC corresponding to each coordinate point and depth, and construct a soil moisture difference curve. The soil moisture difference ΔC=C'-C, where C' is the soil moisture value corresponding to the crop soil moisture curve, C is the soil moisture value corresponding to the predicted soil moisture curve, the horizontal coordinate of the soil moisture difference curve is the period unit within the prediction period, and the vertical coordinate is the soil moisture value. It can be calibrated in advance according to the current time and the growth time point of the crop, so that the horizontal coordinate can be normalized for easy analysis and processing, which will not be described in detail here. By constructing a soil moisture difference curve, the soil moisture can be displayed more intuitively, which is convenient for analyzing countermeasures.

[0039] S5. Determine whether the soil moisture difference ΔC of the soil moisture difference curve is greater than a preset stage standard soil moisture difference ΔC 标 If yes, an alarm signal is sent, if no, no alarm signal is sent. Stage standard soil moisture difference ΔC 标 This value will change according to the growth stage of the crop and the different soil depths. For the same crop, different growth stages require different moisture values. For example, the soil moisture required within 0.5m for wheat sowing is 16-20%, and the moisture required within 1-3m for wheat pollination is 6-10%. The specific details are not described here. Therefore, the standard moisture difference ΔC 标 This value changes according to the growth stage of the crop. Its specific value can be obtained based on experience or experiments, and will not be elaborated here. The alarm signal sent may include the coordinate range corresponding to the point, the soil moisture difference ΔC equal to the stage standard soil moisture difference ΔC 标 The corresponding time point and soil depth can be obtained so that we can obtain the irrigation area unit that needs irrigation and the corresponding time, which is convenient for later water management.

[0040] S6. Irrigate the irrigation area according to the alarm signal, because the alarm signal contains the coordinate range corresponding to the point and the soil moisture difference ΔC is equal to the stage standard soil moisture difference ΔC. 标 We can irrigate according to the irrigation unit corresponding to the coordinate area based on the time point and soil depth. The unit water consumption of irrigation can be calculated by the soil depth and soil moisture difference ΔC. The specific unit water consumption of irrigation can be , where ρ 土 is the soil density under the current average soil moisture, ρ 水 is the density of water, h 2is the effective depth of soil evaluation, a is the soil property coefficient, and h is the evaluation depth of the land in the irrigation area. The time point of irrigation can be determined according to the corresponding soil depth and soil penetration time. The specific time can be obtained based on experience, and the details will not be repeated here. By managing the water use in the irrigation area through this method, the growth of crops can be intervened, and water resources can be effectively utilized. At the same time, the yield of crops is avoided due to lack of water, and effective control is achieved. The irrigation area coordinates can be irrigated in a targeted manner, avoiding water resource waste and excessive soil moisture causing growth interference. Improve the utilization rate of water resources and reasonable allocation and utilization.

[0041] Example 2 Reference Figure 5 The present invention also proposes an irrigation area water management system based on digital twins, comprising: The soil moisture detection module is buried in different soil depths in the irrigation area to detect and obtain soil moisture data in the irrigation area. The required soil moisture detection modules are pre-buried in each irrigation unit according to the detection depth. These soil moisture detection modules are installed at different depths, and the depth setting needs to be determined according to the root distribution of the crops.

[0042] The crop information acquisition module is used to obtain the crop planting information of each irrigation unit in the irrigation area. The crops planted in each irrigation unit are the same type of crops. In actual planting operations, the land is also divided into units, so this method is closer to the actual planting situation. The crop information may include the type of crops planted, the growth stage of the crops, and the soil moisture data required for each growth stage of the crops.

[0043] The weather information acquisition module is used to obtain weather data within the forecast period. The forecast period is the length of time we can predict future weather, and the forecast period is generally 5-15 days. Weather data may include surface temperature and rainfall, etc. The values ​​of surface temperature and rainfall can be obtained by looking up the local meteorological bureau to obtain the weekly weather forecast, etc.

[0044] The analysis and construction module is used to construct a crop moisture curve based on crop information; based on the moisture data, a soil moisture surface of different soil depths and a moisture curve predicted for each coordinate point and soil depth in the irrigation area within the measurement period are constructed. This can ensure water management, improve the effective use of water resources, avoid unnecessary waste of water resources, and better meet the needs of crop growth. The predicted moisture curve is compared with the crop moisture curve, and the moisture difference ΔC corresponding to each coordinate point and depth is calculated, and a moisture difference curve is constructed. The moisture difference ΔC=C'-C, wherein C' is the moisture value corresponding to the crop moisture curve, C is the moisture value corresponding to the predicted moisture curve, the horizontal coordinate of the moisture difference curve is the period unit within the prediction period, and the vertical coordinate is the moisture value.

[0045] The analysis and judgment module is used to judge whether the soil moisture difference ΔC of the soil moisture difference curve is greater than a preset stage standard soil moisture difference ΔC 标 If yes, an alarm signal is sent, if no, no alarm signal is sent. Stage standard soil moisture difference ΔC 标 This value will change according to the growth stage of the crop and the different soil depth changes. For the same crop, the soil moisture values ​​required at different growth stages are different. 标 This value changes according to the growth stage of the crop.

[0046] An irrigation control module is used to irrigate the irrigation area according to the alarm signal; Irrigation water consumption , where ρ 土 is the soil density under the current average soil moisture, ρ 水 is the density of water, h 2 is the effective depth of soil evaluation, a is the soil property coefficient, and h is the evaluation depth of the land in the irrigation area. The time point of irrigation can be determined according to the corresponding soil depth and soil penetration time. The specific time can be obtained based on experience, and the details will not be repeated here. By managing the water use in the irrigation area through this method, the growth of crops can be intervened, and water resources can be effectively utilized. At the same time, the yield of crops is avoided due to lack of water, and effective control is achieved. The irrigation area coordinates can be irrigated in a targeted manner, avoiding water resource waste and excessive soil moisture causing growth interference. Improve the utilization rate of water resources and reasonable allocation and utilization.

[0047] The above specific implementations do not constitute a limitation on the protection scope of the present disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A method for irrigation area water management based on digital twins, characterized in that: The irrigation area water management method based on digital twins includes the following steps: S1. Detect and obtain soil moisture data of the irrigation area, and construct soil moisture surfaces of different soil depths based on the soil moisture data; S2, obtaining crop planting information of each irrigation unit in the irrigation area, and constructing a crop soil moisture curve based on the crop information; S3. Obtain the soil moisture curve for each coordinate point and soil depth prediction within the prediction period according to the weather data within the prediction period; S4, comparing the predicted soil moisture curve with the crop soil moisture curve, calculating the soil moisture difference ΔC corresponding to each coordinate point and depth, and constructing a soil moisture difference curve; S5. Determine whether the soil moisture difference ΔC of the soil moisture difference curve is greater than a preset stage standard soil moisture difference ΔC 标 ; If yes, an alarm signal is sent, if no, no alarm signal is sent.

2. The irrigation area water management method based on digital twin according to claim 1 is characterized in that: The alarm signal sent includes the corresponding coordinates, the soil moisture difference ΔC equal to the stage standard soil moisture difference ΔC 标 The corresponding time point and soil depth as well as the soil moisture difference ΔC.

3. The irrigation area water management method based on digital twin according to claim 2 is characterized in that: The irrigation area water management method based on digital twins also includes: S6. irrigate the irrigation area according to the alarm signal; Water consumption per unit of irrigation , where ρ 土 is the soil density under the current average soil moisture, ρ 水 is the density of water, h2 is the effective depth of soil evaluation, a is the soil property coefficient, and h is the evaluation depth of the land in the irrigation area.

4. The irrigation area water management method based on digital twin according to claim 1 is characterized in that: The specific method of obtaining the soil moisture surface includes: constructing a plane coordinate system, the soil moisture data of the irrigation area mainly includes the installation coordinates of the soil moisture detection module (x i ,y i , z i ) and the detection value C i , where i is the number of the soil moisture detection module; (x i ,y i ) is the plane coordinate of the soil moisture detection module numbered i, z i is the buried depth of the soil moisture detection module numbered i, and the detection value C i Detect the value for the soil moisture detection module numbered i; calculate and obtain the soil moisture value C, and then implant the soil moisture values ​​of each soil depth layer into the plane coordinate system to obtain the soil moisture surface.

5. The irrigation area water management method based on digital twin according to claim 1 is characterized in that: The method for constructing a crop soil moisture curve includes: constructing a plane coordinate system, the horizontal coordinate of the plane coordinate system is the time point of the crop growth stage, and the vertical coordinate is the soil moisture value of each soil depth layer, the minimum soil moisture value corresponding to each soil depth required for crop growth is implanted into the coordinate system, and then each point is connected according to time to obtain the crop soil moisture curve.

6. The irrigation area water management method based on digital twin according to claim 1 is characterized in that: Weather data includes surface temperature and rainfall.

7. The irrigation area water management method based on digital twin according to claim 1 is characterized in that: The method for constructing a predicted soil moisture curve includes: constructing a plane coordinate system, the horizontal coordinate is each period unit in the prediction period, the vertical coordinate is the soil moisture value, and calculating the predicted soil moisture value C of each coordinate point in the prediction period. n , and then the predicted soil moisture value C n The periodic units are implanted into the coordinate system and connected in sequence to form the predicted soil moisture curve.

8. The irrigation area water management method based on digital twin according to claim 7 is characterized in that: The cycle unit is 1 day.

9. An irrigation area water management system based on digital twins, characterized in that: include: The soil moisture detection module is buried in different soil depths of the irrigation area and is used to detect and obtain soil moisture data of the irrigation area; A crop information acquisition module is used to obtain crop planting information of each irrigation unit in the irrigation area; A weather information acquisition module, which is used to obtain weather data within the forecast period; An analysis and construction module is used to construct a crop moisture curve based on crop information; to construct a soil moisture surface at different soil depths and a predicted moisture curve for each coordinate point and soil depth in the irrigation area within the prediction period based on the moisture data; The analysis and judgment module is used to judge whether the soil moisture difference ΔC of the soil moisture difference curve is greater than a preset stage standard soil moisture difference ΔC 标 ; If yes, an alarm signal is sent, if no, no alarm signal is sent.

10. The irrigation area water management system based on digital twin according to claim 9, characterized in that: The irrigation area water management system based on digital twin also includes: An irrigation control module, which is used to irrigate the irrigation area according to the alarm signal; Irrigation water consumption , where ρ 土 is the soil density under the current average soil moisture, ρ 水 is the density of water, h2 is the effective depth of soil evaluation, a is the soil property coefficient, and h is the evaluation depth of the land in the irrigation area.

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