A method suitable for paddy field scale irrigation and drainage simulation

Abstract

The application discloses a method suitable for paddy field scale irrigation and drainage simulation and belongs to the technical field of agricultural irrigation model application. The method comprises the following steps: a formula for the relationship between the water content of the plough layer soil of paddy and the water level of the plough layer soil is established through field measurement; field irrigation test measured data and corresponding irrigation mode index data are acquired; the measured data are taken as model input data; aiming at the input data, index data are used for simulation calculation to acquire daily scale field water quantity change data; the water quantity change data are used for model training according to the measured field water level change data to generate a paddy field irrigation and drainage model; target data are acquired and input into the paddy field irrigation and drainage model for operation to acquire paddy field scale irrigation and drainage simulation data, and irrigation and drainage are simulated according to the simulation data. The application solves the problem that the paddy field irrigation and drainage process simulation is difficult due to the frequent changes of the wet layer and the non-water layer of the paddy field caused by the dry-wet alternate irrigation of the paddy field in the plain river network area in the south.

Description

Technical Field

[0001] This invention relates to the field of agricultural irrigation model application technology, and more specifically, to a method for simulating irrigation and drainage at the field scale in rice paddies. Background Technology

[0002] The main sources of water in paddy fields are rainfall, irrigation, and groundwater recharge. Water consumption in the field mainly includes evaporation, transpiration, seepage, and drainage. While some water parameters can be obtained through field experiments, these are time-consuming and costly. Modeling the process of water changes in paddy fields can simulate the variations of various water parameters under different climatic conditions and irrigation patterns in a short time. This not only guides the design of field experiments but also provides a reference for various field water management issues such as the selection of regional irrigation patterns, the formulation of irrigation systems, and the assessment of agricultural water use. However, simulating paddy field water balance faces three main challenges: First, the frequent exchange of water levels between the water layer and the dry layer significantly impacts evaporation, transpiration, and seepage. Second, when there is no water layer in the field, soil moisture content needs to be calculated, which is complex, highly random, and less convenient and accurate than water level observation. Third, paddy field water changes frequently and significantly, involving many water parameters with complex conversion relationships, making simulation difficult. Summary of the Invention

[0003] To address the above problems, this invention proposes a method for simulating irrigation and drainage at the field scale in rice paddies, comprising:

[0004] A formula relating soil moisture content and soil water level in the rice tillage layer was established through field measurements.

[0005] Obtain measured data from field irrigation experiments and corresponding irrigation model index data. Use the measured data as model input data. Based on the index data, perform simulation calculations to obtain daily field water volume change data. Train the model based on the measured field water level change data to generate a rice field irrigation and drainage model.

[0006] The target data is obtained and input into the paddy field irrigation and drainage model for calculation to obtain simulated data of paddy field-scale irrigation and drainage. The simulation data is then used to simulate irrigation and drainage.

[0007] Optional experimental data include: meteorological data, rainfall data, irrigation data, and drainage data.

[0008] Optional data include meteorological data, rainfall data, irrigation data, and drainage data.

[0009] The rainfall and meteorological data were obtained through meteorological stations near the fields.

[0010] The irrigation and drainage data were obtained through field trials.

[0011] Optional target data includes: meteorological, rainfall, and irrigation pattern data.

[0012] Optional, simulation data, including: daily-scale water level change data in the field and daily-scale data of water quantity elements.

[0013] Optional daily-scale data for water quantity elements include:

[0014] Evaporation and transpiration of water in the field, deep seepage, and groundwater recharge.

[0015] Optional irrigation modes include conventional irrigation and water-saving irrigation, and their indicators mainly include: upper limit of irrigation, lower limit of irrigation, and upper limit of rainwater storage.

[0016] Alternatively, the methods for obtaining evapotranspiration, deep seepage, and groundwater recharge are as follows:

[0017] When there is a water layer on the surface of the field and evaporation is not restricted:

[0018] Evaporation ET c The calculation method is as follows:

[0019]

[0020] in K is used as a reference for crop evapotranspiration. cmax The maximum crop coefficient;

[0021] The deep permeability DP is selected based on the field soil type and the type of crop.

[0022] Groundwater recharge CR is set to 0;

[0023] When there is no water layer on the surface of the field, transpiration and evaporation are limited:

[0024] Evaporation ET c The calculation method is as follows:

[0025]

[0026] in, This refers to the evapotranspiration of rice. Evapotranspiration is the evapotranspiration of a reference crop under standard conditions. The basic crop coefficient, It is the soil evaporation coefficient.

[0027] The calculation method for deep leakage (DP) is as follows:

[0028]

[0029] Where WT is the root zone soil water level, H is the root zone soil water level when the soil moisture content reaches field capacity, and DP is the root zone soil water level. max WT represents the maximum value of the water level-related deep seepage component when WT equals H, and m is the seepage constant;

[0030] Groundwater recharge CR is set to 0;

[0031] When under water stress:

[0032] When there is no water layer on the field surface:

[0033] Evaporation ET c The calculation method is as follows:

[0034]

[0035] Among them, ET c This represents the actual evaporation and transpiration of rice during that period. This represents the crop coefficient for a given time period. The soil moisture stress coefficient for that period;

[0036] The deep seepage rate DP is calculated according to the above-mentioned calculation formula when there is no water layer on the field surface.

[0037] The calculation method for groundwater recharge CR is as follows:

[0038]

[0039] Where b and n are fitting coefficients, CR max WT represents the maximum groundwater recharge, and WT represents the root zone soil water level.

[0040] This invention solves the problem that frequent exchanges of water levels between water-bearing and waterless layers in the field can have a significant impact on evaporation, seepage, and other factors. It also addresses the issue of shallow groundwater depth and close hydraulic connection between soil water and groundwater. Attached Figure Description

[0041] Figure 1 This is a flowchart of a method for simulating irrigation and drainage at the field scale in rice paddies according to the present invention. Detailed Implementation

[0042] Exemplary embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0043] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0044] To address the above problems, this invention proposes a method suitable for field-scale irrigation and drainage simulation in rice paddies, such as... Figure 1 As shown, it includes:

[0045] A method for simulating irrigation and drainage at the field scale in rice paddies includes:

[0046] A formula relating soil moisture content and soil water level in the rice tillage layer was established through field measurements.

[0047] Obtain measured data from field irrigation experiments and corresponding irrigation model index data. Use the measured data as model input data. Based on the index data, perform simulation calculations to obtain daily field water volume change data. Train the model based on the measured field water level change data to generate a rice field irrigation and drainage model.

[0048] The target data is obtained and input into the paddy field irrigation and drainage model for calculation to obtain simulated data of paddy field-scale irrigation and drainage. The simulation data is then used to simulate irrigation and drainage.

[0049] The experimental data include: meteorological data, rainfall data, irrigation data, and drainage data.

[0050] Meteorological data, rainfall data, irrigation data, and drainage data;

[0051] The rainfall and meteorological data were obtained through meteorological stations near the fields.

[0052] The irrigation and drainage data were obtained through field trials.

[0053] The target data includes: meteorological, rainfall, and irrigation pattern data.

[0054] The simulation data includes: daily-scale water level change data in the field and daily-scale data of water quantity elements.

[0055] Daily-scale data for water quantity elements include:

[0056] Evaporation and transpiration of water in the field, deep seepage, and groundwater recharge.

[0057] Optional irrigation modes include conventional irrigation and water-saving irrigation, and their indicators mainly include: upper limit of irrigation, lower limit of irrigation, and upper limit of rainwater storage.

[0058] The methods for obtaining evapotranspiration, deep seepage, and groundwater recharge are as follows:

[0059] When there is a water layer on the surface of the field and evaporation is not restricted:

[0060] Evaporation ET c The calculation method is as follows:

[0061]

[0062] in K is used as a reference for crop evapotranspiration. cmax The maximum crop coefficient;

[0063] The deep permeability DP is selected based on the field soil type and the type of crop.

[0064] Groundwater recharge CR is set to 0;

[0065] When there is no water layer on the surface of the field, transpiration and evaporation are limited:

[0066] Evaporation ET c The calculation method is as follows:

[0067]

[0068] in, This refers to the evapotranspiration of rice. Evapotranspiration is the evapotranspiration of a reference crop under standard conditions. The basic crop coefficient, It is the soil evaporation coefficient.

[0069] The calculation method for deep leakage (DP) is as follows:

[0070]

[0071] Where WT is the root zone soil water level, H is the root zone soil water level when the soil moisture content reaches field capacity, and DP is the root zone soil water level. maxWT represents the maximum value of the water level-related deep seepage component when WT equals H, and m is the seepage constant;

[0072] Groundwater recharge CR is set to 0;

[0073] When under water stress:

[0074] When there is no water layer on the field surface:

[0075] Evaporation ET c The calculation method is as follows:

[0076]

[0077] Among them, ET c This represents the actual evaporation and transpiration of rice during that period. This represents the crop coefficient for a given time period. The soil moisture stress coefficient for that period;

[0078] The deep seepage rate DP is calculated according to the above-mentioned calculation formula when there is no water layer on the field surface.

[0079] The calculation method for groundwater recharge CR is as follows:

[0080]

[0081] Where b and n are fitting coefficients, CR max WT represents the maximum groundwater recharge, and WT represents the root zone soil water level.

[0082] The formula for the relationship between positions;

[0083] The present invention will be further described below with reference to embodiments:

[0084] Obtain measured data from field irrigation experiments and corresponding irrigation model index data. Use measured meteorological data, rainfall data, irrigation data, drainage data, etc. as input data for the model. Based on the principle of water balance, simulate and calculate the daily field water volume changes. Use measured field water level change data as a basis to train the model, obtain the optimal parameter combination, and generate a rice field irrigation and drainage model.

[0085] After the model is built, input the meteorological, rainfall and irrigation pattern data that need to be simulated and calculated, and output the daily water level changes in the field. If necessary, the daily scale data of water volume elements such as irrigation water volume, drainage water volume, evaporation and transpiration, and seepage volume during the simulation period can also be calculated.

[0086] The formula relating soil moisture content in the topsoil layer (approximately 0-20cm) to soil water level needs to be obtained through field measurements. These measurements require installing a 30cm water gauge in the field to record the water level. A cylindrical PVC pipe, approximately 6cm in diameter and 40cm long, is selected. A cylindrical area 15cm below the field surface is drilled with 5mm diameter perforations every 2cm, maintaining connectivity within the topsoil layer to observe changes in soil water level. Another PVC pipe of the same diameter, 60cm long, is selected. A cylindrical area 15cm below the pipe wall is drilled with 5mm diameter perforations every 2cm to observe changes in groundwater level. Irrigation begins at the dry layer (where only groundwater level readings are available), continues above the surface, and then gradually recedes downwards. A fitting curve is established between the topsoil moisture content (0-20cm) and soil water level in the topsoil layer. Soil moisture content is measured using the oven-drying method.

[0087] The above measured data includes: field rainfall data, irrigation data, drainage data, meteorological data, and water quantity data;

[0088] Water quantity data, including:

[0089] Evaporation and transpiration of water in the field, deep seepage, and groundwater recharge.

[0090] Irrigation modes include conventional irrigation and water-saving irrigation, and their main indicators include: upper limit of irrigation, lower limit of irrigation, and upper limit of rainwater storage.

[0091] The methods for obtaining evapotranspiration, deep seepage, and groundwater recharge are as follows:

[0092] (1) When there is a water layer on the surface of the field and evaporation is not restricted:

[0093] Evaporation ET c The calculation method is as follows:

[0094]

[0095] in, To reference crop evapotranspiration, the Penman-Monteith formula recommended in FAO-56 (Allen et al., 1998) was used for calculation. The calculations were based on a reference surface defined by the FAO as a grassland with uniform height, vigorous growth, complete soil cover, and adequate water supply, at a height of 0.12m and a surface resistance of 70sm. -1 Reflectivity 0.23 The standard state. The calculation is independent of the water level in the field; at the same location and time, it depends only on the meteorological data of that day. The calculation formula is as follows:

[0096]

[0097] In the formula G represents net radiation at the canopy surface (mm / d), G represents soil heat flux (MJ / m2d), and T represents daily average air temperature (°C). The wind speed (m / s) is at a height of 2m. The saturated vapor pressure is (kPa). This represents the actual water vapor pressure (kPa). The slope of the water vapor pressure curve (kPa / ℃) is given. This is the hygrometer constant (kPa / ℃). These parameters can be calculated from meteorological observation data and geographical information. The data to be observed include daily maximum temperature, daily minimum temperature, wind speed, relative humidity, sunshine duration, latitude and elevation of the test area, etc.

[0098] Parameter calculation:

[0099] (1) Atmospheric pressure (P)

[0100] Atmospheric pressure P is the pressure exerted by the weight of the Earth's atmosphere. It is related to altitude, but the effect is relatively small; in calculation programs, using the average value from a single location is sufficient to meet accuracy requirements. For standard atmosphere, the temperature is assumed to be 20°C. P can be calculated using a simplified, idealized law of air:

[0101]

[0102] (2) Latent heat of vaporization )

[0103] The latent heat of vaporization, λ, represents the energy required to convert a unit mass of water from a liquid state to water vapor under constant pressure and temperature conditions. As a function of temperature, the latent heat of vaporization varies with temperature; less energy is required at higher temperatures than at lower temperatures. Since λ varies slightly with temperature within the normal temperature range, a single value is used in the simplification of the Penman-Monteith formula, i.e., λ = λ / 2. =2.45 MJ / kg, this value is equivalent to an air temperature of approximately 20 degrees Celsius. Latent heat at that time.

[0104] (3) Hygrometer constant (γ)

[0105] The hygrometer constant γ is expressed by the formula:

[0106]

[0107] In the formula: Hygrometer constant (kPa / P is atmospheric pressure (kPa); The ratio of water vapor to dry air molecular weight is 0.622; Latent heat of vaporization: 2.45 (MJ / kg); Specific heat at constant pressure (MJ / kg·℃).

[0108] (4) Average temperature over the period

[0109] For the standardization case, the average temperature over a 24-hour period is defined as the average of the daily maximum temperature (Tmax) and the daily minimum temperature (Tmin), rather than as the average of hourly temperature observations.

[0110] (5) Mean saturated vapor pressure (es)

[0111] When establishing a correlation between saturated vapor pressure and air temperature, saturated vapor pressure can be calculated using air temperature, and the relationship expression is as follows:

[0112]

[0113] In the formula: is the saturated water vapor pressure (kPa) at air temperature T; T is the air temperature (°C).

[0114] Due to the nonlinearity of the above equations, the average saturated vapor pressure for each ten-day period or month should be calculated using the average vapor pressure at the corresponding daily average maximum and minimum temperatures during that period.

[0115]

[0116] (6) The slope of the curve relating saturated water vapor pressure to temperature ( )

[0117] When calculating water demand, the slope Δ of the curve relating saturated vapor pressure and temperature is required. The slope of the curve at different temperatures is given by the following formula:

[0118]

[0119] (7) Actual water vapor pressure (ea):

[0120]

[0121] In the formula: This represents the average relative humidity over a given period.

[0122] (8) Net radiation (Rn)

[0123] Net radiation (Rn) is the difference between the received net shortwave radiation (Rns) and the lost net longwave radiation (Rnl):

[0124]

[0125] in:

[0126]

[0127]

[0128]

[0129]

[0130]

[0131]

[0132]

[0133]

[0134]

[0135] In the formula: Total solar radiation over clear sky (MJ / m2·d); The solar constant is 0.0820 min⁻¹. It is the reciprocal of the relative distance between the Earth and the Sun; Geographical latitude, The magnetic declination of the sun; For solar or shortwave radiation (MJ / m2·d); is the solar hour angle; n is the actual sunshine duration; N is the maximum astronomical sunshine duration; The regression constant represents the portion of outer space radiation that reaches the Earth's surface on a dark day; This refers to the portion of outer space radiation that reaches the Earth's surface on a clear, cloudless day. Solar radiation under clear skies; This refers to reflectivity or canopy reflectivity.

[0136] (9) Soil heat flux (G)

[0137] Compared to Rn, soil heat flux is smaller, especially when the surface is covered by vegetation. Therefore, when the calculation time step is 24 hours or longer, it is based on the idea that soil temperature follows the degassing temperature conduction principle.

[0138]

[0139] In the formula: G is the soil heat flux. For soil heat capacity, Let i be the air temperature at time i. Let i be the air temperature at time i-1; The length of the time interval; Effective soil depth.

[0140] (10) Wind speed

[0141] Wind speeds vary at different heights above the soil surface. Surface friction tends to slow wind speeds above the surface. Wind speeds are lowest at the surface and increase with altitude. Therefore, anemometers are placed at a standard height, such as 10m for meteorology and 2m or 3m for agro-meteorology. For water requirement calculations, wind speeds must be measured at a height of 2m above the surface. To adjust for wind speed values ​​measured at heights other than the standard height, measurements on mowed pasture surfaces can be calculated using logarithmic wind speed profile analysis.

[0142]

[0143] In the formula: The wind speed is 2 meters above the ground. Let be the wind speed measured at a point zm above the ground, where z is the measurement height above the ground.

[0144] For the maximum crop coefficient, where K cmax The following formula can be used to calculate:

[0145]

[0146] in The wind speed (m / s) is at a height of 2m. The minimum relative humidity is given by h, where h is the crop height (mm). The basic crop coefficient varies with different growth stages of the crop. The FAO provides the basic crop coefficient values ​​for rice under standard conditions at the initial growth stage, mid-growth stage, and late growth stage: , , .

[0147] The deep permeability DP is selected based on the field soil type and the type of crop.

[0148] Groundwater recharge CR is set to 0;

[0149] (2) When there is no water layer on the field surface, transpiration and evaporation are restricted:

[0150] Evaporation ET c The calculation method is as follows:

[0151]

[0152] In the formula This refers to the evapotranspiration of rice. Evapotranspiration is the evapotranspiration of a reference crop under standard conditions. The basic crop coefficient, It is the soil evaporation coefficient.

[0153] Under non-standard conditions (i.e., the minimum daily relative humidity is not 45%, and the wind speed is not 2 m / s), it is necessary to... Make corrections:

[0154]

[0155] In the formula The wind speed (m / s) is at a height of 2m. is the minimum daily relative humidity (%), and h is the height of the rice plant (m).

[0156] Ke is used to describe soil evaporation, and the calculation formula is as follows:

[0157]

[0158] In the formula, De,i-1 represents the cumulative soil evaporation (mm) from rainfall or irrigation day i to the previous calculation day; REW represents the soil evaporation (mm) during the atmospheric evaporation control phase; and TEW represents the total evaporation (mm) after rainfall or irrigation. The FAO provides corresponding reference values ​​for different soil texture types.

[0159] The calculation method for deep leakage (DP) is as follows:

[0160]

[0161] In the formula, WT is the root zone soil water level, H is the soil water level corresponding to the soil moisture content reaching field capacity, and DP is the soil water level. max WT represents the maximum value of the deep seepage component related to water level when WT equals H, and m is the seepage constant.

[0162] Groundwater recharge CR is set to 0;

[0163] (3) When under water stress:

[0164] When there is no water layer on the field surface:

[0165] The calculation method for evapotranspiration (ETC) is as follows:

[0166]

[0167] In the formula, ETc represents the actual evaporation and transpiration of rice during the specified time period. This represents the crop coefficient for a given time period. The soil moisture stress coefficient for that period is given.

[0168] The formula for calculating Ks is as follows:

[0169]

[0170] In the formula, TAW is the total effective water volume in the root zone (mm); Dr is the water consumption volume in the root zone (mm); and p is the ratio of the effective water absorbed by the crop from the root zone to the total effective water volume TAW when the crop is not under water stress.

[0171] The deep seepage rate DP is calculated according to the above-mentioned calculation formula when there is no water layer on the field surface.

[0172] The calculation method for groundwater recharge CR is as follows:

[0173]

[0174] In the formula, b and n are fitting coefficients, CRmax is the maximum groundwater recharge, and WT is the root zone soil water level.

[0175] Rainfall data, irrigation data, drainage data, and meteorological data;

[0176] The rainfall and meteorological data were obtained through meteorological stations near the fields.

[0177] Irrigation and drainage data were obtained through field trials.

[0178] This invention solves the problem that frequent exchanges of water levels between water-bearing and waterless layers in the field can have a significant impact on evaporation, seepage, and other factors. It also addresses the issue of shallow groundwater depth and close hydraulic connection between soil water and groundwater.

[0179] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can 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. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0180] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0181] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0182] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0183] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0184] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for simulating irrigation and drainage at the field scale in rice paddies, the method comprising: A formula relating soil moisture content and soil water level in the rice tillage layer was established through field measurements. Obtain measured data from field irrigation experiments and corresponding irrigation model index data. Use the measured data as model input data. Based on the index data, perform simulation calculations to obtain daily field water volume change data. Train the model based on the measured field water level change data to generate a rice field irrigation and drainage model. The target data is obtained and input into the paddy field irrigation and drainage model for calculation to obtain the simulation data of paddy field-scale irrigation and drainage. The simulation data is used to simulate irrigation and drainage. The simulation data includes daily water level change data and daily water quantity data. The daily water quantity data includes: evaporation and transpiration of paddy field water, deep seepage and groundwater recharge. The methods for obtaining the evaporation, deep seepage, and groundwater recharge are as follows: When there is a water layer on the surface of the field and evaporation is not restricted: Evaporation ET c The calculation method is as follows: ； in K is used as a reference for crop evapotranspiration. cmax The maximum crop coefficient; The deep permeability DP is selected based on the field soil type and the type of crop. Groundwater recharge CR is set to 0; When there is no water layer on the surface of the field, transpiration and evaporation are limited: Evaporation ET c The calculation method is as follows: ； in, This refers to the evapotranspiration of rice. Evapotranspiration is the evapotranspiration of a reference crop under standard conditions. The basic crop coefficient, It is the soil evaporation coefficient; The calculation method for deep leakage (DP) is as follows: ； Where WT is the root zone soil water level, H is the root zone soil water level when the soil moisture content reaches field capacity, and DP is the root zone soil water level. max WT represents the maximum value of the water level-related deep seepage component when WT equals H, and m is the seepage constant; Groundwater recharge CR is set to 0; When under water stress: When there is no water layer on the field surface: Evaporation ET c The calculation method is as follows: ； Among them, ET c This represents the actual evaporation and transpiration of rice during that period. This represents the crop coefficient for a given time period. The soil moisture stress coefficient for that period; The deep seepage rate DP is calculated according to the above-mentioned calculation formula when there is no water layer on the field surface. The calculation method for groundwater recharge CR is as follows: ； Where b and n are fitting coefficients, CR max WT represents the maximum groundwater recharge, and WT represents the root zone soil water level.

2. The method according to claim 1, wherein the experimentally measured data includes: Meteorological data, rainfall data, irrigation data, and drainage data.

3. The method according to claim 2, wherein the meteorological data, rainfall data, irrigation data, and drainage data are acquired in the following ways: The rainfall and meteorological data were obtained through meteorological stations near the fields; The irrigation and drainage data were obtained through field trials.

4. The method according to claim 1, wherein the target data comprises: Meteorological, rainfall, and irrigation pattern data.

5. The method according to claim 1, wherein the irrigation mode includes: Conventional irrigation and water-saving irrigation Its main indicators include: upper limit of irrigation, lower limit of irrigation, and upper limit of rainwater storage.

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