A method and system for quantitatively determining the water flow rate and flow volume of drip irrigation water and fertilizer integration

Abstract

This invention discloses a method and system for quantitatively determining irrigation volume and flow velocity in drip irrigation fertigation, belonging to the field of agricultural water-saving irrigation technology. The method involves acquiring crop parameters, soil parameters, and irrigation management parameters for the target crop; calculating the irrigation volume based on the crop and soil parameters; determining a first upper limit for flow velocity based on soil infiltration characteristics, a second upper limit based on root depth control, and a lower limit based on the requirement of uniform wet bulb stacking; comparing the first and second upper limits and determining the smaller value as the upper limit; determining the flow velocity constraint range based on the lower and upper limits; and determining the irrigation duration and number of irrigations based on the irrigation volume and the flow velocity constraint range. This invention determines irrigation volume and flow velocity as independent parameters, using the dual constraint of the upper limit to prevent surface water accumulation and deep seepage, and ensuring uniform distribution of drip irrigation through the lower limit, thus achieving precise design of drip irrigation parameters.

Description

Technical Field

[0001] This invention belongs to the field of agricultural water-saving irrigation technology, and in particular relates to a method and system for quantitatively determining irrigation volume and flow rate in drip irrigation fertigation. Background Technology

[0002] Drip irrigation technology, as one of the core technologies of modern water-saving irrigation, plays an increasingly important role in agricultural production. Drip irrigation fertigation technology is a modern agricultural technology that integrates irrigation and fertilization. It delivers a water-fertilizer mixture evenly, regularly, and quantitatively to the soil around the crop roots through a pipeline system, achieving simultaneous water and fertilizer supply. In the design and operation of a drip irrigation system, irrigation volume and flow rate are two of the most critical parameters, directly affecting irrigation effectiveness and water and fertilizer utilization efficiency.

[0003] However, traditional methods for determining drip irrigation system parameters have the following technical problems: First, traditional methods typically determine the irrigation volume based on the crop's water requirements and then work backward to deduce the flow rate. This approach has a fundamental physical flaw: the flow rate is an independent parameter determined by the specifications and operating pressure of the drip irrigation system, rather than a derived parameter derived from the irrigation volume.

[0004] Second, traditional methods determine irrigation volume and flow rate based on different criteria, and there is no inherent physical connection between the two, which may lead to mismatched parameter combinations.

[0005] Third, different types of crops exhibit significant differences in root depth, leaf transpiration characteristics, and nutrient absorption patterns, necessitating different irrigation and fertilization strategies. Existing methods often employ uniform parameter determination rules, failing to adequately consider the impact of crop type on these parameters.

[0006] Fourth, the water and fertilizer requirements of crops at different growth stages are dynamic, while most existing methods use static parameters, which cannot adapt to the dynamic changes in crop requirements during the growth process.

[0007] Fifth, there are significant differences in the infiltration characteristics and water distribution patterns of different soils, and existing methods fail to consider how to ensure that irrigation water is distributed precisely in the root zone to avoid deep seepage or surface water accumulation.

[0008] Sixth, the root depths of different types of crops vary significantly, and existing methods do not consider the constraining effect of root depth on flow velocity.

[0009] Therefore, it is urgent to research and develop a quantitative method for determining irrigation volume and flow velocity, to determine them as independent parameters, and then to verify their compatibility through the water balance equation, so as to provide a scientific and reasonable basis for determining parameters for drip irrigation fertigation systems. Summary of the Invention

[0010] To address the aforementioned technical problems, this invention provides a method for quantitatively determining irrigation volume and flow rate in drip irrigation fertigation, comprising the following steps: Obtain crop parameters, soil parameters, and irrigation management parameters for the target crop; Calculate the irrigation amount based on the crop parameters and the soil parameters; Based on the soil parameters and the planted area in the crop parameters, a first upper limit of flow velocity based on soil infiltration characteristics is determined. Based on the crop parameters and the soil parameters, a second upper limit for flow velocity based on root depth control is determined; Based on the crop parameters and the soil parameters, determine the lower limit of the flow rate based on the requirement of uniform stacking of wet balls; Compare the magnitudes of the first flow velocity limit and the second flow velocity limit, and determine the smaller of the two values ​​as the flow velocity limit; The flow velocity constraint interval is determined based on the lower flow velocity limit and the upper flow velocity limit; Based on the irrigation volume and the flow velocity constraint range, determine the irrigation volume parameters and flow velocity parameters.

[0011] Optionally, obtaining the crop parameters, soil parameters, and irrigation management parameters of the target crop includes: Obtain the target crop's species, planting density, planting area, crop growth period, crop coefficient, and reference crop evapotranspiration. Get the soil texture type; Obtain irrigation duration.

[0012] Optionally, the irrigation amount is calculated based on the crop parameters and the soil parameters, including: Determine the irrigation correction factor based on the soil texture type; The irrigation amount is calculated based on the reference crop evapotranspiration, the crop coefficient, the planting area, and the irrigation amount correction coefficient.

[0013] Optionally, a first upper limit for flow velocity based on soil infiltration characteristics is determined according to the soil parameters and the planted area in the crop parameters, including: Based on the soil texture type, determine the soil saturated hydraulic conductivity and safety factor; The first upper limit of flow velocity is determined based on the soil saturated hydraulic conductivity, the planting area, and the safety factor.

[0014] Optionally, determining a second upper limit for flow velocity based on root depth control, according to the crop parameters and the soil parameters, includes: The upper limit of leakage is determined based on the type of the target crop and the growth period of the crop; Based on the soil texture type, determine the range of variation of effective soil water content; Determine the humidity coefficient based on the root system type of the target crop; The second flow velocity upper limit is determined based on the upper limit of seepage, the range of variation of effective soil moisture content, the planting area, the irrigation duration, and the humidity coefficient.

[0015] Optionally, based on the crop parameters and the soil parameters, a lower limit for the flow rate based on the requirement of uniform stacking of wet bulbs is determined, including: The target radius of the wet ball is determined based on the type of target crop, planting spacing, and soil texture type. The drip irrigation area coefficient is determined based on the target radius of the moistening bulb and the planting spacing; The lower limit of the flow rate is determined based on the target radius of the wetting ball, the range of variation of the effective soil moisture content, the wetting coefficient, the planting area, the drip irrigation area coefficient, and the irrigation duration.

[0016] Optionally, the method further includes: Calculate the amount of water required for each fertilization based on the irrigation volume and fertilization interval; The irrigation duration and number of irrigations are determined based on the amount of water required for each fertilization and the flow rate.

[0017] This invention also provides a quantitative determination system for irrigation volume and flow rate in drip irrigation fertigation, comprising: The data acquisition module is used to acquire crop parameters, soil parameters, and irrigation management parameters for the target crop. An irrigation calculation module is used to calculate the irrigation amount based on the crop parameters and the soil parameters; The flow velocity determination module is used to determine a first upper limit of flow velocity based on soil infiltration characteristics according to the planting area in the soil parameters and crop parameters, a second upper limit of flow velocity based on root depth control according to the crop parameters and soil parameters, a lower limit of flow velocity based on the requirement of uniform stacking of wet bulbs according to the crop parameters and soil parameters, compare the size of the first upper limit of flow velocity and the second upper limit of flow velocity and determine the smaller value of the two as the upper limit of flow velocity, and determine the flow velocity constraint interval according to the lower limit of flow velocity and the upper limit of flow velocity; The parameter output module is used to output the irrigation volume and the flow velocity constraint range.

[0018] The present invention also provides an electronic device including a processor, a memory, and an input / output interface, wherein the processor is configured to execute a computer program stored in the memory to implement the steps of the method.

[0019] The present invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method.

[0020] Compared with the prior art, the present invention has the following advantages and technical effects: This invention determines irrigation volume and flow velocity as independent parameters, overcoming the problem of lost physical meaning caused by the inverse deduction of flow velocity from irrigation volume in traditional methods. Two upper limits for flow velocity are determined based on soil infiltration characteristics and crop root depth, with the smaller value taken as the final upper limit. This effectively prevents surface water accumulation and deep seepage, ensuring irrigation water is concentrated in the crop root layer and avoiding leaching losses of water and fertilizer. Simultaneously, a lower limit for flow velocity is determined based on the requirement for uniform stacking of wet bulbs, ensuring effective overlap between adjacent dripper wet bulbs, avoiding uneven distribution and the formation of dry zones in multi-drip irrigation, and improving irrigation uniformity. Furthermore, by dynamically determining crop coefficients based on crop type, and dynamically determining irrigation volume correction coefficients and soil infiltration parameters based on soil texture, irrigation volume and flow velocity can be adapted to the water and fertilizer requirements of different crops at different growth stages and the infiltration and water-holding characteristics of different soils, achieving precise and scientific design of drip irrigation parameters. The method of this invention has clear steps and rigorous logic, providing a scientific and reasonable basis for determining parameters for drip irrigation fertigation systems and effectively improving water and fertilizer utilization efficiency. Attached Figure Description

[0021] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a flowchart illustrating the method for quantitatively determining irrigation volume and flow rate according to an embodiment of the present invention. Detailed Implementation

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0024] Example 1 like Figure 1 As shown in this embodiment, a method for quantitatively determining irrigation volume and flow rate in drip irrigation fertigation is provided, including the following steps: Obtain the target crop's species, planting density, planting area, crop growth period, crop coefficient, and reference crop evapotranspiration; obtain the soil texture type; and obtain the irrigation duration. The irrigation amount correction coefficient is determined based on the soil texture type, and the irrigation amount is calculated based on the reference crop evapotranspiration, the crop coefficient, the planting area, and the irrigation amount correction coefficient. The soil saturated hydraulic conductivity and safety factor are determined based on the soil texture type. Based on the soil saturated hydraulic conductivity, the planting area, and the safety factor, a first flow velocity upper limit based on soil infiltration characteristics is determined. The upper limit of seepage is determined based on the type of target crop and the growth period of the crop; the range of variation of effective soil moisture content is determined based on the soil texture type; the wetting coefficient is determined based on the root system type of the target crop; and a second upper limit of flow velocity based on root depth control is determined based on the upper limit of seepage, the range of variation of effective soil moisture content, the planting area, the irrigation duration, and the wetting coefficient. The target radius of the wet ball is determined based on the type of target crop, planting spacing and soil texture type. The drip irrigation area coefficient is determined based on the target radius of the wet ball and the planting spacing. The lower limit of the flow rate based on the uniform stacking requirement of the wet balls is determined based on the target radius of the wet ball, the range of variation of the effective soil moisture content, the wetting coefficient, the planting area, the drip irrigation area coefficient and the irrigation duration. Compare the magnitudes of the first flow velocity limit and the second flow velocity limit, and determine the smaller of the two values ​​as the flow velocity limit; The flow velocity constraint interval is determined based on the lower flow velocity limit and the upper flow velocity limit; Based on the irrigation volume and the flow rate constraint range, output the irrigation volume and flow rate.

[0025] Specifically, it can be divided into the following steps: S1: Obtain the target crop's water requirement parameters, planting density, planting area data, soil texture type, and irrigation duration; S2: Determine the irrigation correction coefficient based on the crop type and establish an irrigation calculation model Q=ET0×Kc×A×Fw.

[0026] Where Q is the irrigation amount (L / d), ET0 is the reference crop evapotranspiration (mm / d), Kc is the crop coefficient, reflecting the differences in water requirements among different crops, and A is the planting area (m²). 2 ), where Fw is the irrigation correction factor; S3: Based on crop root depth and soil infiltration characteristics, establish a flow velocity determination model to determine the lower and upper bounds of the flow velocity: S3a: Determine the upper limit of flow velocity v based on soil infiltration characteristics. max-infiltration=Ks×A×F safety ×10, where Ks is the soil saturated hydraulic conductivity and A is the planting area (m²). 2 ), F safety To ensure safety and prevent surface water accumulation; S3b: Determine the upper limit of flow velocity v based on crop root depth. max-leaching =(d max ×Δθ×A×10) / (t×ρ), where d max The upper limit of seepage is given, Δθ is the range of variation of effective soil moisture content, and A is the planting area (m²). 2 ), where t is the irrigation duration and ρ is the wetting coefficient, to prevent deep seepage; S3c: Determine the lower limit of flow velocity v based on the requirement of uniform stacking of wetted spheres. min =(R target ×Δθ×ρ×A×β×10) / t, where R target Let Δθ be the target radius of the wetting ball, Δθ be the range of effective soil moisture content, and A be the irrigated area (m²). 2 ), where t is the irrigation duration, ρ is the humidity coefficient, β is the drip irrigation area coefficient, and β is the proportion of drip irrigation area to planting area; S3d: Comprehensive determination of the upper limit of flow velocity v max =min(v max-infiltration , v max-leaching ); S4: Based on the lower and upper bounds of the flow velocity, control the flow velocity to ensure that the target flow velocity v satisfies v min ≤v≤v max ; S5: Based on the independent calculation results of irrigation volume and flow rate, calculate the amount of water required for each fertilization by means of the fertilization period interval.

[0027] Specifically, the formula is explained in detail below: In the irrigation calculation model Q=ET0×Kc×A×Fw, Q is the irrigation amount in L / d; ET0 is the reference crop water requirement, calculated according to the FAO-56 method; Kc is the crop coefficient, reflecting the difference in water requirements of different crops at different growth stages, with a value range of 0.4 to 1.2; A is the planting area, determined according to the actual planting situation, in m²; and Fw is the irrigation correction coefficient, adjusted according to soil texture, with a value range of 0.8 to 1.2.

[0028] The upper limit of flow velocity v is determined based on soil infiltration characteristics. max-infiltration =Ks×A×F safety ×10, where v max-infiltrationThe upper limit of flow velocity is based on infiltration characteristics, in L / h; Ks is the soil saturated hydraulic conductivity, reflecting the soil's ability to absorb water, in cm / h; A is the planting area, determined according to actual planting conditions, in m²; F safety For safety, the value ranges from 0.5 to 0.9. Upper limit of flow velocity v max-infiltration The physical meaning is: when the flow rate is too fast, the water accumulates on the surface and cannot infiltrate in time, which will form surface water accumulation or runoff. Therefore, it is necessary to set an upper limit on the flow rate to prevent surface water accumulation.

[0029] The upper limit of flow velocity v is determined based on the depth of crop roots. max-leaching =(d max ×Δθ×A×10) / (t×ρ), where, v max-leaching The upper limit of flow rate based on leakage control, in L / h; d max The upper limit of seepage is determined based on the crop root depth, in cm; Δθ is the range of effective soil moisture content; A is the planting area, in m²; t is the irrigation duration, in h; ρ is the wetting coefficient. max-leaching The physical meaning is: when the flow rate is too fast, the water penetrates below the root layer during the irrigation time, causing deep seepage loss. Therefore, it is necessary to set an upper limit on the flow rate to prevent deep seepage.

[0030] Determine the upper limit of flow velocity based on comprehensive factors: v max =min(v max-infiltration , v max-leaching Take the smaller of the two upper limits to ensure that the requirements for preventing water accumulation and leakage are met at the same time.

[0031] The lower limit of flow velocity v is determined based on the requirement of uniform stacking of wetted spheres. min =(R target ×Δθ×ρ×A×10) / t, where, v min This is the lower limit of flow rate, in L / h; R target The target radius of the wetting bulb is determined based on soil texture and crop type, ranging from 10 to 30 cm; Δθ represents the range of effective soil moisture content; ρ is the wetting coefficient; A is the planting area in m²; t is the irrigation duration in hours; and β is the drip irrigation area coefficient, which is the proportion of drip-irrigated area to the total planting area: β = (R target / planting spacing) 2 v min The physical meaning is to ensure that the wetted bulbs produced by a single dripper can spread horizontally sufficiently, and that the wetted bulbs from adjacent drippers can overlap well, thus guaranteeing a uniform distribution of irrigation from multiple drippers. If the flow rate is too low, the horizontal diffusion of the wetted bulbs will be insufficient, and a dry zone will form between adjacent drippers, resulting in uneven irrigation.

[0032] Based on the lower and upper limits of the flow velocity, control the flow velocity so that the target flow velocity v satisfies: v min ≤v≤v max The flow rate is determined independently by the specifications and working pressure of the drip irrigation system and is not affected by the amount of water being irrigated.

[0033] The invention also provides a drip irrigation fertigation parameter determination system, including a data acquisition module, an irrigation volume calculation module, a flow rate determination module, and a parameter output module, for implementing the aforementioned method.

[0034] The rules for crop type classification and parameter determination are as follows: Based on crop morphological characteristics and growth habits, crops are divided into three main types: leafy vegetables, root vegetables, and fruit vegetables. Their growth period includes four stages: seedling stage, rapid growth stage, yield formation stage, and late growth stage. Parameters for different growth stages of different crop types are as follows: The crop coefficient Kc is determined as shown in Table 1: Table 1 The biological significance of Kc lies in the fact that even under the same meteorological conditions, different crops consume different amounts of water through transpiration due to differences in leaf morphology, canopy structure, leaf area index, and plant height. Kc is used to quantify these differences—for example, tomatoes have large leaves and high transpiration rates, resulting in a Kc of 1.0-1.2; while wheat leaves turn yellow at maturity, with a Kc of only 0.2-0.3. Kc varies with the crop's growth stage: it is low during the seedling stage, maximum during the vigorous growth stage, and decreases during maturity, reflecting the changing patterns of water requirements during crop growth.

[0035] Leakage limit d max The determination is shown in Table 2: d max It is the maximum depth to which water is allowed to penetrate. The core principle is that water can only reach the root layer and cannot penetrate below the roots.

[0036] Table 2 d max Biological significance: It characterizes the effective depth of crop root distribution—it determines the maximum depth irrigation water should reach, essentially "keeping water where the roots can absorb it." If water penetrates beyond this depth, the roots cannot utilize it, resulting in deep seepage losses and fertilizer leaching; conversely, if water remains at a depth of d... max The above demonstrates that irrigation was even and just right. max The specific requirements vary depending on the crop type and growth stage, and therefore need to be dynamically determined based on the actual planting conditions.

[0037] Soil texture type classification and parameter determination rules: Soil is classified into four types based on its texture: sandy soil, sandy loam, loam, and clay loam. The parameters for each type of soil texture are as follows: The irrigation water correction factor Fw is shown in Table 3: Table 3 The physical meaning of Fw: Sandy soil has poor water retention, while clay has strong water retention. Therefore, sandy soil requires high irrigation volume and low flow rate to ensure sufficient moisture and prevent nutrient leaching. Clay soil requires low irrigation volume and high flow rate to prevent flooding and expand the moist body.

[0038] The saturated hydraulic conductivity Ks is shown in Table 4: Table 4 The physical significance of Ks: Saturated hydraulic conductivity Ks is a core parameter in soil science, representing the ability of water to pass through the soil per unit time when the soil is fully saturated. Water passes through quickly in coarse-porous soils (sandy soils), while water has difficulty passing through in fine-porous soils (clay soils). Ks determines the upper limit of the flow rate in a drip irrigation system: if the flow rate is higher than Ks, the water will infiltrate completely and accumulate on the surface; if the flow rate is lower than Ks, the water can be properly absorbed by the soil.

[0039] Safety factor F safety As shown in Table 5: Table 5 F safety The physical meaning of safety factor F: safety This is an empirical compensation for soil heterogeneity. In reality, the permeability of soil varies greatly in the field—in the same plot of land, some areas infiltrate quickly while others infiltrate slowly, and even the Ks at different depths in the same location can differ by several times. Therefore, when designing the flow rate, the theoretical Ks value cannot be used directly, but must be multiplied by a coefficient less than 1 to leave a margin, ensuring that even in local "weak points," there will be no surface water accumulation or deep seepage.

[0040] The effective soil water content Δθ is shown in Table 6: Table 6 The physical meaning of Δθ: Soil effective water content Δθ is the difference between soil field capacity and wilting coefficient, representing the actual amount of water available to crops in the soil. Sandy soil has coarse particles and large pores, so water flows away easily and can retain less, hence Δθ is small; clay soil has fine particles and can hold more water, hence Δθ is large.

[0041] The wetting coefficient ρ is shown in Table 7: Table 7 The physical meaning of ρ: ρ is the wetting coefficient, which describes the ratio of vertical infiltration to lateral diffusion of water in the soil: when the ρ value is large, water mainly infiltrates vertically downwards; when the ρ value is small, water mainly diffuses laterally.

[0042] Target radius R of the wetted sphere target As shown in Table 8: R target It is the target radius of the wetting ball, which refers to the radius of the wetting area formed by a single dripper in the soil.

[0043] Table 8 R target The physical meaning of the wetted sphere target radius R target R refers to the radius of the moistened area formed by a single dripper in the soil. During drip irrigation, each dripper supplies water to the soil, and the water diffuses outwards under gravity and capillary action, forming a nearly spherical moistened area. target The size of the wetted bulbs determines whether adjacent drippers can be effectively stacked—too small and the drying zone separates; too large and excessive overlap wastes water. Meanwhile, R... target Closely related to soil texture: Sandy soil has a predominantly vertical water infiltration and weak lateral diffusion, resulting in a deeper and narrower wetting ball; clay soil, on the other hand, has a shallower and wider wetting ball.

[0044] This embodiment also provides a quantitative determination system for irrigation volume and flow rate in drip irrigation fertigation, including: The data acquisition module is used to acquire crop parameters, soil parameters, and irrigation management parameters for the target crop. An irrigation calculation module is used to calculate the irrigation amount based on the crop parameters and the soil parameters; The flow velocity determination module is used to determine a first upper limit of flow velocity based on soil infiltration characteristics according to the planting area in the soil parameters and crop parameters, a second upper limit of flow velocity based on root depth control according to the crop parameters and soil parameters, a lower limit of flow velocity based on the requirement of uniform stacking of wet bulbs according to the crop parameters and soil parameters, compare the size of the first upper limit of flow velocity and the second upper limit of flow velocity and determine the smaller value of the two as the upper limit of flow velocity, and determine the flow velocity constraint interval according to the lower limit of flow velocity and the upper limit of flow velocity; The parameter output module is used to output the irrigation volume and the flow velocity constraint range.

[0045] On the other hand, this embodiment also provides an electronic device, including a memory, a processor, and a computing program stored in the memory and executable on the processor, wherein the processor implements the method when executing the computing program.

[0046] On the other hand, this embodiment also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the method.

[0047] Example 2 This embodiment provides a method for quantitatively determining the irrigation volume and flow rate in drip irrigation fertigation, including the following steps: S1: Obtain the basic parameters of the target crop.

[0048] S2: Calculate the irrigation volume according to the FAO-56 method.

[0049] S3: Determine the flow velocity constraint range based on soil infiltration characteristics, crop root depth, and the requirement for uniform stacking of wet bulbs.

[0050] S4: Select the drip irrigation system specifications to ensure the target flow rate is within the constraints.

[0051] S5: Plan the flow rate and calculate the drip irrigation duration by determining the fertilization interval.

[0052] Specifically, it includes: In step S1, the basic parameters of the target crop include: crop type is tomato (medium-root / fruiting vegetable), planting area is 1000 m², soil type is loam, and growth stage is fruiting stage. The reference crop water requirement ET0 is calculated to be 1 mm / d according to the FAO-56 method.

[0053] In step S2, the irrigation correction coefficient Fw is determined to be 0.9 (soil), the tomato fruiting period crop coefficient Kc is 1.1, and the irrigation calculation model Q=ET0×Kc×A×Fw is applied for calculation: Q = 1 × 1.1 × 1000 × 0.9 = 990 L / d; In step S3, the flow velocity constraint range is determined based on soil infiltration characteristics, crop root depth, and the requirement for uniform stacking of wet bulbs: Soil infiltration characteristics analysis: The saturated hydraulic conductivity of the loam is Ks = 3 cm / h, the effective water content varies within a range of Δθ = 0.15, and the safety factor F... safety =0.7; Root depth determination: Tomatoes are medium-root crops, with an upper limit of permeability d. max =60cm, wetting coefficient ρ=0.5; Flow rate limit (to prevent water accumulation): v max-infiltration =Ks×A×F safety ×10=3×1000×0.7×10=21000L / h; Flow rate limit (leakage prevention): Set irrigation duration t=3h, then vmax-leaching =(dmax×Δθ×A×10) / (t×ρ)=(60×0.15×1000×10) / (3×0.5)=60000 L / h; Overall flow rate limit: v max =min(21000, 60000)=21000L / h; Drip irrigation characteristic analysis: target radius R of the wet bulb target =25cm; Drip irrigation area coefficient β=0.25; Lower limit of flow velocity (uniformity): v min =(R target ×Δθ×ρ×A×β×10) / t=(25×0.15×0.5×1000×0.25×10) / 3=1652.5L / h.

[0054] In step S4, the selected drip irrigation system specifications should meet the constraint that 1652.5 ≤ v ≤ 21000.

[0055] In step S5, fertilization during the peak fruiting period of tomatoes is generally done every 14-20 days, with a 15-day interval chosen: Q_actual = Q × T = 990 × 15 = 14850L; The daily irrigation water volume for fertilization is Q=14850L. Based on 3 hours of irrigation, the irrigation rate is 4950L / h.

[0056] Example 3 This embodiment provides a quantitative determination system for irrigation volume and flow rate in drip irrigation fertigation, including: 1. Data acquisition module; The data acquisition module is the foundation of the entire system, responsible for collecting and acquiring various types of raw data. This module includes the following sub-units: Crop information acquisition unit: used to input and store basic crop information, including crop type, variety, planting date, planting density, and other data; Meteorological data interface unit: used to connect to meteorological data sources and obtain meteorological parameters such as temperature, humidity, wind speed, and radiation; Soil parameter acquisition unit: used to acquire soil parameter data such as soil texture, soil moisture content, and soil fertility; Irrigation system parameter storage unit: used to store drip irrigation system management parameters, including planting area, fertilization duration and other parameters.

[0057] 2. Irrigation volume calculation module; The irrigation calculation module calculates the crop irrigation amount based on the raw data provided by the data acquisition module. This module includes the following functional components: Crop water requirement calculation unit: The reference crop water requirement ET0 is calculated based on the FAO-56 method and meteorological data; Crop coefficient determination unit: Determine the crop coefficient Kc by referring to tables or calculation based on crop type and growth period; Unit for determining irrigation correction coefficient: Determine the irrigation correction coefficient Fw based on crop type and soil texture; Irrigation volume calculation unit: Based on the irrigation volume calculation model Q=ET0×Kc×A×Fw, it calculates and outputs the irrigation volume Q.

[0058] 3. Flow rate calculation module; The flow rate calculation module calculates the irrigation rate based on the raw data provided by the data acquisition module. This module includes the following functional components: Unit for determining the upper limit parameter of infiltration velocity: Determine the soil saturated hydraulic conductivity Ks and safety factor F based on soil texture type. safety ; Unit for determining the upper limit parameter of seepage velocity: Determine the upper limit of seepage d based on crop type and growth stage. max The effective water content Δθ and the wetting coefficient ρ are determined based on the soil texture type. Unit for determining the lower limit parameter of flow velocity: Based on crop type, planting spacing and soil texture type, determine the target radius R of the wetted bulb. target The drip irrigation area coefficient β is determined based on the target radius of the wetted bulb and the planting spacing. Flow velocity range determination unit: based on formula v max-infiltration =Ks×A×F safety ×10 confirms the upper limit of the infiltration velocity, according to the formula v max-leaching =(d max ×Δθ×A×10) / (t×ρ) confirms the upper limit of the leakage velocity, according to the formula v max =min(v max-infiltration , v max-leaching The upper limit of the flow velocity is determined comprehensively based on the formula v. min =(R target ×Δθ×ρ×A×β×10) / t confirms the lower limit of flow velocity. Based on the determined lower and upper limits of flow velocity, the appropriate range of flow velocity is determined.

[0059] 4. Parameter output module; The parameter output module is responsible for visualizing the calculation and optimization results and supports parameter export and printing. This module includes the following functional components: Data display unit: Displays the results of parameters such as irrigation volume and flow rate in the form of charts; Report generation unit: Automatically generates parameter determination reports, including input parameters, calculation process, output results, etc. Parameter export unit: Supports exporting parameter results to standard format files, facilitating integration with irrigation control systems; Historical record unit: Stores historical parameter records to facilitate data tracing and comparative analysis.

[0060] This embodiment also included comparative verification of parameter determination for different crops: To verify the universality and effectiveness of the method of this invention, three typical crops were used as examples for comparative verification. Cabbage (leafy vegetable), radish (root vegetable), and tomato (fruit vegetable) were selected as the research objects, with a planting area of ​​1000m². 2 The irrigation period is 3 hours.

[0061] Table 9 The parameter determination results for the three crops are shown in Table 9. As can be seen from Table 9, the method of the present invention can automatically adjust the flow rate adjustment coefficient and irrigation volume correction coefficient according to the water requirement characteristics of different crop types, and calculate the optimal irrigation volume and flow rate parameters suitable for various crops.

[0062] Analysis of dynamic changes during the reproductive period: Taking tomatoes as an example, this study analyzes the variation patterns of parameters at different growth stages. The growth cycle of tomatoes can be divided into four stages: seedling stage, flowering stage, fruiting stage, and ripening stage. The crop coefficient, flow rate regulation coefficient, and coupling index differ significantly at each stage.

[0063] Table 10 The parameter changes of tomatoes at different growth stages are shown in Table 10. The above analysis results show that the method of the present invention can dynamically adjust various parameters according to the changes in the water requirement characteristics of crops at different growth stages, so as to ensure that the irrigation strategy matches the crop growth needs.

[0064] Based on the verification of the above three embodiments, the following conclusions can be drawn: First, the method of the present invention can automatically adjust parameters according to different crop types, and is applicable to the determination of drip irrigation system parameters for various crops such as leafy vegetables, root vegetables, and fruit vegetables; Second, the method of the present invention can dynamically adjust parameters according to the crop growth period to achieve precise matching between irrigation strategy and crop growth needs; Third, the system structure provided by the method of the present invention is complete and the functions are well-defined, and it can be easily integrated into the existing drip irrigation and fertigation control system.

[0065] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for quantitatively determining irrigation volume and flow rate in drip irrigation fertigation, characterized in that, Includes the following steps: Obtain crop parameters, soil parameters, and irrigation management parameters for the target crop; Calculate the irrigation amount based on the crop parameters and the soil parameters; Based on the soil parameters and the planted area in the crop parameters, a first upper limit of flow velocity based on soil infiltration characteristics is determined. Based on the crop parameters and the soil parameters, a second upper limit for flow velocity based on root depth control is determined; Based on the crop parameters and the soil parameters, determine the lower limit of the flow rate based on the requirement of uniform stacking of wet balls; Compare the magnitudes of the first flow velocity limit and the second flow velocity limit, and determine the smaller of the two values ​​as the flow velocity limit; The flow velocity constraint interval is determined based on the lower flow velocity limit and the upper flow velocity limit; Based on the irrigation volume and the flow velocity constraint range, determine the irrigation volume parameters and flow velocity parameters.

2. The method according to claim 1, characterized in that, The acquisition of crop parameters, soil parameters, and irrigation management parameters for the target crop includes: Obtain the target crop's species, planting density, planting area, crop growth period, crop coefficient, and reference crop evapotranspiration. Get the soil texture type; Obtain irrigation duration.

3. The method according to claim 1, characterized in that, Calculate the irrigation amount based on the crop parameters and the soil parameters, including: Determine the irrigation correction factor based on the soil texture type; The irrigation amount is calculated based on the reference crop evapotranspiration, the crop coefficient, the planting area, and the irrigation amount correction coefficient.

4. The method according to claim 1, characterized in that, Based on the soil parameters and the planted area in the crop parameters, a first upper limit for flow velocity based on soil infiltration characteristics is determined, including: Based on the soil texture type, determine the soil saturated hydraulic conductivity and safety factor; The first upper limit of flow velocity is determined based on the soil saturated hydraulic conductivity, the planting area, and the safety factor.

5. The method according to claim 1, characterized in that, Based on the crop parameters and the soil parameters, a second upper limit for flow velocity controlled by root depth is determined, including: The upper limit of leakage is determined based on the type of the target crop and the growth period of the crop; Based on the soil texture type, determine the range of variation of effective soil water content; Determine the humidity coefficient based on the root system type of the target crop; The second flow velocity upper limit is determined based on the upper limit of seepage, the range of variation of effective soil moisture content, the planting area, the irrigation duration, and the humidity coefficient.

6. The method according to claim 5, characterized in that, Based on the crop parameters and the soil parameters, determine the lower limit of the flow velocity according to the requirement of uniform stacking of wet bulbs, including: The target radius of the wet ball is determined based on the type of target crop, planting spacing, and soil texture type. The drip irrigation area coefficient is determined based on the target radius of the moistening bulb and the planting spacing; The lower limit of the flow rate is determined based on the target radius of the wetting ball, the range of variation of the effective soil moisture content, the wetting coefficient, the planting area, the drip irrigation area coefficient, and the irrigation duration.

7. The method according to claim 1, characterized in that, Also includes: Calculate the amount of water required for each fertilization based on the irrigation volume and fertilization interval; The irrigation duration and number of irrigations are determined based on the amount of water required for each fertilization and the flow rate.

8. A quantitative determination system for irrigation volume and flow rate in drip irrigation fertigation, characterized in that, include: The data acquisition module is used to acquire crop parameters, soil parameters, and irrigation management parameters for the target crop. An irrigation calculation module is used to calculate the irrigation amount based on the crop parameters and the soil parameters; The flow velocity determination module is used to determine a first upper limit of flow velocity based on soil infiltration characteristics according to the planting area in the soil parameters and crop parameters, a second upper limit of flow velocity based on root depth control according to the crop parameters and soil parameters, a lower limit of flow velocity based on the requirement of uniform stacking of wet bulbs according to the crop parameters and soil parameters, compare the size of the first upper limit of flow velocity and the second upper limit of flow velocity and determine the smaller value of the two as the upper limit of flow velocity, and determine the flow velocity constraint interval according to the lower limit of flow velocity and the upper limit of flow velocity; The parameter output module is used to output the irrigation volume and the flow velocity constraint range.

9. An electronic device, characterized in that, It includes a processor, a memory, and an input / output interface, wherein the processor is configured to execute a computer program stored in the memory to implement the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The storage medium stores a computer program that, when executed by a processor, implements the steps of the method according to any one of claims 1 to 7.

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