Variable rate fertilization control system and method

Abstract

The invention provides a variable-rate fertilization control system and method, and relates to the technical field of variable-rate fertilization control. A soil water quantity diffusion model is established through a water quantity diffusion model module according to soil characteristics of a region to be fertilized, a drip irrigation fertilization range is determined through a drip irrigation range calculation module, and the volume of the drip irrigation fertilization range is calculated; the fertilization amount calculation module is used for performing real-time concentration detection on the types of fertilizer elements in a drip irrigation fertilization range in which the fertilizer element detection plants are located, and judging the demand quantity and the lowest absorption content of the plants on each type of fertilizer elements in a fertilization period; the fertilization safety module calculates the maximum fertilization amount according to the soil inorganic salt content and the volume of the drip irrigation fertilization range, formulates a fertilization strategy through the concentration matching module, calculates the fertilization drip irrigation speed and the fertilization drip irrigation water amount according to the water amount diffusion model and the drip irrigation fertilization range, and calculates the fertilizer preparation concentration of each fertilizer element type according to the fertilization drip irrigation water amount.

Description

Technical Field

[0001] The present invention relates to the technical field of variable-rate fertilization, and in particular to a variable-rate fertilization control system and method. Background Art

[0002] Traditional drip fertigation systems are widely used in agricultural production, but most suffer from uneven fertilization, fertilizer waste, and poor fertilization effectiveness. Due to significant differences between soil water diffusion characteristics and plant root distribution, traditional drip fertigation systems struggle to precisely control fertilization based on specific soil conditions and plant growth stages. Furthermore, existing drip fertigation systems often lack dynamic regulation mechanisms, making it impossible to monitor changes in fertilizer element concentrations and plant fertilizer needs in real time. This can result in excessive or insufficient fertilization, impacting plant growth and soil health.

[0003] Furthermore, soil fertilizer capacity and inorganic salt concentrations significantly impact plant growth, yet variations in these factors are often not fully considered in traditional fertilization programs. Existing technologies, which mostly focus on static fertilization schemes, are unable to adapt to varying soil conditions and plant growth cycles, resulting in inefficient fertilizer utilization and potentially even leading to problems such as soil salinization.

[0004] The existing technology, published as CN 119692952 A, describes a variable-rate fertilization control system and method for tobacco fields. The system includes a sensing data acquisition module that collects soil moisture data via a soil moisture sensor and simultaneously monitors crop growth data to synthesize real-time soil and growth data. Time series analysis is performed on the real-time soil and growth data to identify data trends and anomalies, generating trend analysis results. This system collects soil moisture and crop growth data and combines them with time series analysis to rapidly identify trends and anomalies, improving prediction accuracy. However, core issues include uneven irrigation, low absorption efficiency, failure to consider salt damage risks, and delayed response.

[0005] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the Invention

[0006] The object of the present invention is to provide a variable fertilization control system and method to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A variable fertilization control system, comprising:

[0009] A water diffusion model module is used to establish a water diffusion model between the soil water diffusion range and the drip irrigation position, drip irrigation speed, and drip irrigation water volume during drip irrigation according to the soil characteristics of the area to be fertilized;

[0010] A drip irrigation range calculation module is used to obtain the root growth range of the plant to be fertilized at different growth stages, determine the range of drip irrigation according to the distribution of groundwater layers in the soil characteristics, and calculate the volume of the drip irrigation range;

[0011] A fertilizer amount calculation module is used to randomly select plants in the area to be fertilized as fertilizer element detection plants, perform real-time concentration detection on the fertilizer element types within the drip irrigation fertigation range where the fertilizer element detection plants are located, calculate the rate of change of the content of each type of fertilizer element and the set fertilization cycle, and determine the plant's demand and minimum absorption content for each type of fertilizer element within the fertilization cycle;

[0012] A fertilization safety module is used to obtain the plant's tolerance to inorganic salt concentration and the average soil moisture, calculate the soil's fertilizer element capacity based on the soil's inorganic salt content, and calculate the maximum fertilizer amount based on the capacity and the volume of the drip irrigation range;

[0013] The concentration ratio module is used to formulate a fertilization strategy based on the maximum fertilizer amount, the demand for each type of fertilizer element and the minimum absorption content, calculate the fertilization drip irrigation speed and fertilization drip irrigation water volume based on the water diffusion model and the range of drip irrigation, and calculate the fertilizer concentration of each type of fertilizer element based on the fertilization drip irrigation water volume and fertilization strategy.

[0014] Furthermore, the soil characteristics include soil type, soil gap, soil moisture, distance to groundwater layer, and soil inorganic salt content;

[0015] The specific process of establishing the water diffusion model is as follows:

[0016] With the drip irrigation position during drip fertigation as the center, a three-dimensional coordinate system is established. Humidity sensors are placed equidistantly in four directions of the center position and at different depths. The coordinate positions of the sensor detection points are recorded. Drip irrigation is performed at the center position with different drip irrigation positions, drip irrigation water speeds, and drip irrigation water volumes. The humidity and coordinate positions of each detection point are recorded and combined with soil characteristics to form diffusion data. The drip irrigation position, drip irrigation water volume, and drip irrigation speed form water volume data. The diffusion data is used as the input of the neural network and the water volume data as the output to train the model and obtain a trained water diffusion model.

[0017] The water diffusion model is based on a multi-layer perceptron, specifically including a hidden layer and an output layer;

[0018] Furthermore, the steps for calculating the volume of the drip fertigation range are as follows:

[0019] With the intersection of the plant and the ground as the center point, a three-dimensional coordinate system of the root coordinate range is established. The distribution of the groundwater layer is mapped to the root coordinate system. The range of drip irrigation is determined according to the coordinates of the root growth range and the water distribution coordinates. Based on the range of drip irrigation, the volume of the drip irrigation range is calculated by the integral calculation method.

[0020] Furthermore, the fertilizer element content is calculated based on the real-time concentration of the fertilizer element and soil moisture;

[0021] The method for determining the minimum absorption content is:

[0022] The real-time changes of fertilizer element content in the historical fertilization cycle are counted to form a change curve, the lowest point of the fertilizer element content in each change curve is obtained, and the lowest value of the fertilizer element content of all tested plants is counted, which is the minimum absorption content.

[0023] Furthermore, the calculation method for the demand for fertilizer elements is:

[0024] The formula for calculating the change rate of fertilizer element content is:

[0025]

[0026] Among them, Qf is the change rate of fertilizer element content, is the differential operation of the fertilizer element content Mf, Mf(t) is the fertilizer element content at time t, and Δt is the differential time period;

[0027] Analyze the stability of the fertilizer element content based on the rate of change of the fertilizer element content. When the current fertilizer element content is in a stable state, compare it with the minimum absorption content to determine whether the current fertilizer element content is the minimum absorption content:

[0028] When Qf=0, the current fertilizer element content is judged to be stable;

[0029] When Mf=Czd, it is determined that the current fertilizer element content is the minimum absorption content.

[0030] Furthermore, when the current fertilizer element content is the minimum absorption content, the fertilizer element demand is calculated based on the change rate of the fertilizer element content, the minimum absorption content, the fertilizer element content, and the volume of the drip fertigation range. The calculation formula is:

[0031] MFx=α*ln(Qf max -1)*(Mf max -Czd)*V

[0032] Among them, MFx is the demand for each type of fertilizer element, Qf max Mf is the maximum value of the change rate of fertilizer element content, max is the fertilizer element content at the maximum change rate of the fertilizer element content, Czd is the minimum absorption content, V is the volume of the drip fertigation range, and α is the correction coefficient;

[0033] When Mf>Czd, it is judged that the current fertilizer element content is not the minimum absorption content;

[0034] According to the change rate of fertilizer element content, the fertilizer element reserve content threshold is set, and fertilizer elements are supplemented according to the fertilizer element reserve content threshold. The calculation formula is:

[0035] MB=(Mf MB -Czd)*V

[0036] Among them, MB is the amount of fertilizer element supplement, Mf MB It is the reserve content threshold of fertilizer elements.

[0037] Furthermore, the fertilizer element holding capacity is calculated based on the average soil moisture, inorganic salt concentration tolerance concentration, and soil inorganic salt content;

[0038] The maximum fertilization amount is calculated based on the volume of the drip fertigation range and the fertilizer element capacity;

[0039] Furthermore, the specific method for formulating the fertilization strategy is:

[0040] When the maximum fertilizer application amount is greater than or equal to the required amount of all types of fertilizer elements, the total fertilizer application amount is calculated based on the required amount of each type of fertilizer element:

[0041]

[0042] Among them, Msf is the total amount of fertilizer, Mflx is the type of fertilizer amount, and according to the fertilizer element content Mf, the fertilizer amount is judged as the fertilizer element demand MFx or the fertilizer element supplement MB, Mflx ic is the amount of fertilizer applied for the icth fertilizer element, and nc is the number of fertilizer element types;

[0043] The method for calculating the fertilizer concentration of each fertilizer element type is:

[0044]

[0045] Among them, cfn ic is the fertilizer concentration of the icth fertilizer element, Vsh is the amount of drip irrigation water for fertilization;

[0046] When the maximum fertilizer amount is less than the requirement of all types of fertilizer elements, the fertilizer amount is calculated based on the holding capacity;

[0047]

[0048] Among them, Msf is the total amount of fertilizer, RQf is the fertilizer element capacity,

[0049] The method for calculating the fertilizer concentration of each fertilizer element type is:

[0050]

[0051] Among them, Cfn ic is the fertilizer concentration of the icth fertilizer element, and Vsh is the amount of drip irrigation water for fertilization.

[0052] The present invention further provides a variable rate fertilization control method, which is obtained by executing the above-mentioned variable rate fertilization control system, and specifically comprises the following steps:

[0053] Step 1: Based on the soil characteristics of the area to be fertilized, a water diffusion model is established between the soil water diffusion range and the drip irrigation position, drip irrigation speed, and drip irrigation water volume during drip irrigation.

[0054] Step 2: Obtain the root growth range of the plants to be fertilized at different growth stages, determine the range of drip irrigation according to the distribution of groundwater layers in the soil characteristics, and calculate the volume of the drip irrigation range;

[0055] Step 3: Randomly select plants in the fertilization area as fertilizer element detection plants, conduct real-time concentration detection of fertilizer element types within the drip irrigation fertigation range where the fertilizer element detection plants are located, calculate the change rate of each type of fertilizer element content and set the fertilization cycle, and determine the plant's demand for each type of fertilizer element and the minimum absorption content within the fertilization cycle;

[0056] Step 4: Obtain the plant's tolerance to inorganic salt concentration and the average soil moisture, calculate the soil's fertilizer element capacity based on the soil's inorganic salt content, and calculate the maximum fertilizer amount based on the capacity and the volume of the drip irrigation range;

[0057] Step 5: Formulate a fertilization strategy based on the maximum fertilizer amount, the required amount of each type of fertilizer element and the minimum absorption content; calculate the fertilization drip irrigation rate and fertilization drip irrigation water volume based on the water diffusion model and the scope of drip irrigation; calculate the fertilizer concentration of each type of fertilizer element based on the fertilization drip irrigation water volume and fertilization strategy.

[0058] Compared with the prior art, the present invention has the following beneficial effects: the present invention establishes a soil water diffusion model according to the soil characteristics of the area to be fertilized through the water diffusion model module, determines the range of drip fertigation through the drip irrigation range calculation module, and calculates the volume of the drip fertigation range; the fertilizer amount calculation module performs real-time concentration detection on the fertilizer element types within the drip fertigation range where the fertilizer element detection plant is located, and judges the plant's demand for each type of fertilizer element and the minimum absorption content within the fertilization cycle; the fertilization safety module calculates the maximum fertilizer amount according to the soil inorganic salt content and the volume of the drip fertigation range; the fertilization strategy is formulated through the concentration ratio module; the fertilization drip irrigation speed and the fertilization drip irrigation water volume are calculated according to the water diffusion model and the drip fertigation range; and the fertilizer concentration of each fertilizer element type is calculated according to the fertilization drip irrigation water volume;

[0059] This invention establishes an intelligent control system that comprehensively considers soil characteristics, plant root distribution, water diffusion models, and fertilizer needs. It accurately calculates the range, amount, and concentration of fertigation, effectively addressing the uneven application and fertilizer waste associated with traditional fertigation systems. By monitoring changes in soil fertilizer element concentrations in real time and factoring in the plant's growth stage and root distribution, the system dynamically adjusts the amount and rate of fertilizer application to ensure that plants receive the required amount of fertilizer throughout their growth cycle.

[0060] Furthermore, this solution considers the tolerance range of inorganic salt concentrations in the soil and the fertilizer capacity, avoiding soil salt accumulation caused by excessive fertilization and ensuring the safety and effectiveness of fertilization. By precisely controlling the ratio of fertilizer concentration and quantity, the system not only improves fertilizer utilization but also effectively reduces soil pollution, promoting sustainable agricultural development. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 Schematic diagram of the overall system structure of the present invention;

[0062] Figure 2 Schematic diagram of the overall method of the present invention. DETAILED DESCRIPTION

[0063] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to specific embodiments.

[0064] It should be noted that, unless otherwise defined, the technical or scientific terms used in the present invention should have the usual meanings understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0065] Example:

[0066] See also Figure 1 , the present invention provides a technical solution:

[0067] A variable fertilization control system includes a water diffusion model module, a drip irrigation range calculation module, a fertilizer amount calculation module, a fertilizer safety module, and a concentration ratio module, wherein:

[0068] The water diffusion model module is used to establish a water diffusion model between the soil water diffusion range and the drip irrigation position, drip irrigation water speed, and drip irrigation water volume during drip irrigation according to the soil characteristics of the area to be fertilized.

[0069] Based on the soil characteristics of the area to be fertilized, a water diffusion model is established to accurately simulate the distribution and diffusion of water in the soil, which relates the soil water diffusion range to the drip irrigation position, drip irrigation rate, and drip irrigation volume during drip irrigation. This model not only takes into account the physical properties of the soil (such as soil permeability, moisture, and structure), but also integrates the specific parameters of the drip irrigation equipment, such as drip irrigation position, drip irrigation rate, and drip irrigation volume. This model can accurately calculate the diffusion of fertilization water flow in the soil under dynamically changing environmental conditions, ensuring that the drip irrigation water flow can cover the area required by the plant root system, thereby improving the utilization efficiency of water and fertilizer.

[0070] Existing drip irrigation systems typically use simple models to estimate water diffusion, lacking comprehensive analysis of soil characteristics and drip irrigation equipment parameters, or employ static fertilization patterns that fail to adapt to dynamic changes in soil conditions and fertilization needs. Such systems often result in wasted water and fertilizer, or uneven fertilization, impacting plant growth.

[0071] The establishment of a water diffusion model allows fertilizing water to more precisely penetrate the vicinity of plant roots, maximizing water and fertilizer absorption efficiency. This precise water and fertilizer distribution not only reduces water and fertilizer loss but also improves plant nutrient absorption, promoting healthy plant growth. It also prevents excessive fertilizer from entering groundwater or soil, potentially causing pollution.

[0072] The diffusion of water in the soil is a complex process, which is affected by many factors. The drip irrigation position determines the initial distribution of water in the soil. The drip irrigation water rate will directly affect the diffusion rate of water. The drip irrigation water volume refers to the total amount of water applied to the soil during a certain fertilization cycle. It is closely related to the diffusion range and depth of water in the soil. Different types of soil have different water retention and infiltration capabilities, which directly affect the diffusion behavior of water in the soil. Soil gaps refer to the gaps between soil particles, which directly determine the penetration and diffusion rate of water. The inorganic salt content in the soil affects the permeability of water, especially in soils with higher salinity.

[0073] In this embodiment, the soil characteristics include soil type, soil gap, soil moisture, distance to groundwater layer, and soil inorganic salt content;

[0074] The specific process of establishing the water diffusion model is as follows:

[0075] With the drip irrigation position during drip fertigation as the center, a three-dimensional coordinate system is established. Humidity sensors are placed equidistantly in four directions of the center position and at different depths. The coordinate positions of the sensor detection points are recorded. Drip irrigation is performed at the center position with different drip irrigation positions, drip irrigation water speeds, and drip irrigation water volumes. The humidity and coordinate positions of each detection point are recorded and combined with soil characteristics to form diffusion data. The drip irrigation position, drip irrigation water volume, and drip irrigation speed form water volume data. The diffusion data is used as the input of the neural network and the water volume data as the output to train the model and obtain a trained water diffusion model.

[0076] The water diffusion model is based on a multi-layer perceptron, which specifically includes a hidden layer and an output layer:

[0077] Hidden layer:

[0078] h=σ(W1*x+b1)

[0079] Where g is the output of the hidden layer, σ(·) is the nonlinear activation function, W1 is the weight matrix of the hidden layer, b1 is the bias vector of the hidden layer, and x is the diffusion data input to the model;

[0080] Output layer:

[0081] y=Softmax(W2*h+b2)

[0082] Among them, y is the water volume data output by the model, Softmax is the activation function of the output layer, W2 is the weight matrix of the output layer, and b2 is the bias vector of the output layer.

[0083] The diffusion of water in soil is a complex physical process, involving the interplay of multiple factors, including soil type, moisture, and drip irrigation parameters. This process is often nonlinear and time-varying, with water diffusion behavior varying significantly depending on soil type and environmental conditions. Multilayer perceptrons (MPPs) are well-suited to handling these complex nonlinear relationships, capable of learning nonlinear mappings between multidimensional input features and outputs through training. For water diffusion models, MPPs can automatically learn the most important features for water diffusion from raw input data (such as soil type, moisture, temperature, and salinity). By processing and mapping information through multiple hidden layers, the complex hierarchical structure of the data can be captured. For example, certain soil types may exhibit unique diffusion behaviors under certain conditions, and MPPs can learn these complex relationships through their hidden layers.

[0084] The drip irrigation range calculation module is used to obtain the root growth range of the plant to be fertilized at different growth stages, determine the drip irrigation range according to the distribution of groundwater layers in the soil characteristics, and calculate the volume of the drip irrigation range.

[0085] The root growth range of a plant is a key factor in fertilization effectiveness. A mismatch between the fertilization range and the root growth zone can result in fertilizer waste or suboptimal fertilization results. By considering the root growth patterns of plants at different growth stages, it is possible to accurately determine the appropriate fertilizer placement area. The distribution of groundwater layers in different soils significantly influences the soil's water retention capacity, permeability, and root absorption capacity. By analyzing groundwater distribution, drip irrigation water flow and fertilizer dosage can be more precisely determined, avoiding over- or under-fertilization.

[0086] In this embodiment, the steps for calculating the volume of the drip fertigation range are as follows:

[0087] With the intersection of the plant and the ground as the center point, a three-dimensional coordinate system of the root coordinate range is established. The distribution of the groundwater layer is mapped to the root coordinate system. The range of drip irrigation is determined according to the coordinates of the root growth range and the water distribution coordinates. Based on the range of drip irrigation, the volume of the drip irrigation range is calculated by the integral calculation method:

[0088] The expression formula of the root coordinate range is:

[0089] Gxz=fg(x g ,y g ,z g )

[0090] Among them, Gxz is the root coordinate range, (x g ,y g ,z g ) is the root coordinate, fg is the coordinate range function;

[0091] The expression formula of the groundwater layer distribution is:

[0092] Scz=fs(x s ,y s ,z s )

[0093] Among them, Scz is the distribution of groundwater layers, (x s ,y s ,z s ) is the groundwater layer coordinate, fs is the groundwater layer coordinate range;

[0094] The expression formula of the range of drip irrigation fertigation is:

[0095] Dsz=fd{min(x g ,x s ),min(y g ,y s ),min(z g ,z s )}

[0096] Where Dsz is the range of fertigation, and fd is the function of the range of fertigation;

[0097] The method for calculating the volume of the drip irrigation range is:

[0098]

[0099] Where V is the volume of the drip fertigation range, d represents the min(z g ,z s ) is used for integration operation, and the value of π is 3.14.

[0100] The fertilizer amount calculation module is used to randomly select plants in the fertilization area as fertilizer element detection plants, perform real-time concentration detection on the fertilizer element types within the drip irrigation fertigation range where the fertilizer element detection plants are located, calculate the rate of change of the content of each type of fertilizer element and the set fertilization cycle, and determine the plant's demand for each type of fertilizer element and the minimum absorption content within the fertilization cycle.

[0101] By randomly selecting a few plants for testing fertilizer elements, we ensure that these plants represent the diverse growth conditions and fertilizer absorption patterns within the fertilized area. Different plants may have different growth requirements, sizes, and root development. Selecting a variety of plants for testing provides a more comprehensive and accurate understanding of fertilizer absorption dynamics across the fertilized area.

[0102] Plant fertilizer requirements are not static; they vary depending on factors such as growth stage, climate, and soil conditions. Therefore, monitoring the rate of change in fertilizer element concentrations can provide real-time insights into a plant's actual fertilizer needs. For example, during certain growth stages, particularly during peak growth, a plant may have a higher demand for elements like nitrogen and phosphorus. Monitoring the rate of change in concentrations allows timely identification of these changes in demand and subsequent adjustments to fertilizer application rates. The rate of change in fertilizer element concentrations within a fertilization cycle can reveal how fertilizer is consumed in the soil. This data can be used to determine whether fertilizer has been absorbed or consumed by the plant within the fertilization cycle, helping to accurately determine fertilizer application levels for the next fertilization cycle and avoid over- or under-fertilization. The minimum absorption level (MBL) refers to the lowest concentration at which a plant can effectively absorb a particular fertilizer element. If the fertilizer concentration falls below this level, the plant may not be able to effectively absorb the element, resulting in nutrient deficiencies. By monitoring changes in fertilizer element concentrations, fertilizer applicators can determine whether the soil concentration of a particular fertilizer element is above the minimum for plant absorption, ensuring effective fertilization.

[0103] In this embodiment, the fertilizer element content is calculated based on the real-time concentration of the fertilizer element and soil moisture, and the calculation formula is:

[0104] Mf=Cnd*Hsd

[0105] Among them, Mf is the fertilizer element content, Hsd is the soil moisture, and Cnd is the real-time concentration of the fertilizer element.

[0106] In this embodiment, the method for determining the minimum absorption content is:

[0107] The real-time changes of fertilizer element content in the historical fertilization cycle were counted to form a change curve. The lowest point of the fertilizer element content in each change curve was obtained. The lowest value of the fertilizer element content of all tested plants was counted, which was the minimum absorption content. The calculation formula is:

[0108]

[0109] Among them, Czd is the minimum absorption content, is the minimum fertilizer element content of the iath tested plant.

[0110] In this embodiment, the calculation method for the demand for fertilizer elements is:

[0111] The formula for calculating the change rate of fertilizer element content is:

[0112]

[0113] Among them, Qf is the change rate of fertilizer element content, is the differential operation of the fertilizer element content Mf, Mf(t) is the fertilizer element content at time t, and Δt is the differential time period.

[0114] Analyze the stability of the fertilizer element content based on the rate of change of the fertilizer element content. When the current fertilizer element content is in a stable state, compare it with the minimum absorption content to determine whether the current fertilizer element content is the minimum absorption content:

[0115] When Qf=0, the current fertilizer element content is judged to be stable;

[0116] When Mf=Czd, it is judged that the current fertilizer element content is the minimum absorption content;

[0117] When the current fertilizer element content is the minimum absorption content, the fertilizer element demand is calculated based on the fertilizer element content change rate, the minimum absorption content, the fertilizer element content and the volume of the drip fertigation range. The calculation formula is:

[0118] MFx=α*ln(qf max -1)*(Mf max -Czd)*V

[0119] Among them, MFx is the demand for each type of fertilizer element, Qf max Mf is the maximum value of the change rate of fertilizer element content, max is the fertilizer element content at the maximum change rate of the fertilizer element content, Czd is the minimum absorption content, V is the volume of the drip fertigation range, and α is the correction coefficient;

[0120] When Mf>Czd, it is judged that the current fertilizer element content is not the minimum absorption content;

[0121] According to the change rate of fertilizer element content, the fertilizer element reserve content threshold is set, and fertilizer elements are supplemented according to the fertilizer element reserve content threshold. The calculation formula is:

[0122] MB=(Mf MB -Czd)*V

[0123] Among them, MB is the amount of fertilizer element supplement, Mf MB It is the reserve content threshold of fertilizer elements.

[0124] The fertilization safety module is used to obtain the plant's tolerance to inorganic salt concentration and the average soil moisture, calculate the fertilizer element capacity in the soil based on the soil inorganic salt content, and calculate the maximum fertilizer amount based on the capacity and the volume of the drip irrigation range.

[0125] Different plants have different tolerances to inorganic salts. By understanding the limits of a plant's tolerance to inorganic salt concentrations, you can avoid applying excessive amounts of inorganic salt fertilizers. This helps prevent soil salinization and plant salt damage, ensuring that plants can grow in suitable salt concentrations, and improving plant health and yield.

[0126] The level of inorganic salts in the soil determines how much fertilizer it can hold. By measuring the soil's inorganic salt content, we can accurately determine the soil's fertilizer capacity and ensure that the amount of fertilizer applied is within the soil's tolerance. This precise calculation avoids over-fertilization, thereby reducing fertilizer waste and negative environmental impacts.

[0127] Excessive fertilization can lead to salt accumulation in the soil, which in turn affects the plant's ability to absorb water through its roots and can even cause salt damage. By calculating the amount of fertilizer to be applied based on the plant's tolerance concentration, soil moisture, and inorganic salt content, you can effectively avoid overfertilization and ensure optimal use of fertilizer.

[0128] Existing traditional fertilization methods are often based on experience or fixed formulas, ignoring the differences in soil conditions and plant needs. By designing personalized fertilization plans based on plant salt tolerance, soil moisture, and inorganic salt content, we can more accurately meet the growth needs of different plants in different soil conditions. Existing technologies often rely on fixed fertilizer application patterns and are unable to adjust in real time to soil changes or plant needs. By combining real-time soil and plant data to adjust fertilizer dosage, this solution can dynamically respond to soil and plant changes, achieving precise and flexible fertilization.

[0129] In this embodiment, the fertilizer element holding capacity is calculated by the average soil moisture, the inorganic salt concentration tolerance concentration and the soil inorganic salt content, and the calculation formula is:

[0130] RQf=Hpsd*Cnw-Qwj

[0131] Among them, RQf is the fertilizer element holding capacity, HPsd is the average soil moisture, Cnw is the inorganic salt concentration tolerance concentration, and Qwj is the soil inorganic salt content.

[0132] In this embodiment, the maximum fertilizer amount is calculated by the volume of the drip fertigation range and the fertilizer element capacity, and the specific calculation formula is:

[0133] Msf=RQf*V

[0134] Among them, Msf is the maximum fertilizer amount, and V is the volume of the drip fertigation range.

[0135] The concentration ratio module is used to formulate a fertilization strategy based on the maximum fertilizer amount, the required amount of each type of fertilizer element and the minimum absorption content, calculate the fertilization drip irrigation speed and fertilization drip irrigation water volume based on the water diffusion model and the range of drip irrigation, and calculate the fertilizer concentration of each type of fertilizer element based on the fertilization drip irrigation water volume and fertilization strategy.

[0136] Based on the plant's requirement for each fertilizer element, the amount of fertilizer applied matches the plant's actual needs, avoiding fertilizer waste or poor crop growth due to excessive or insufficient fertilizer. By considering the required and absorbed content of each type of fertilizer, the fertilizer ratio can be adjusted more precisely to ensure that the plant receives all the nutrients it needs, while avoiding excessive accumulation of certain elements in the fertilizer, which can prevent imbalanced fertilizer from affecting crop growth.

[0137] When the maximum fertilizer application rate is greater than or equal to the required amount for all fertilizer types, applying fertilizer according to the required amount for each fertilizer type ensures that the crop receives sufficient amounts of each nutrient element, preventing growth restriction due to insufficient fertilizer. This approach ensures that the amount of each fertilizer element meets the plant's growth needs, thus avoiding fertilizer waste and ensuring that the crop receives adequate nutrition, promoting healthy growth. When the maximum fertilizer application rate is limited, adjusting the fertilizer application rate according to the capacity allows for more efficient utilization of limited fertilizer resources and improves the efficiency of each unit of fertilizer.

[0138] When the maximum fertilizer application limit is less than the crop's total fertilizer element requirement, the system adjusts the amount based on capacity to prevent over-fertilization and avoid plant damage from excessive fertilizer concentrations, such as root burn and leaf wilting. Excessive inorganic salt concentrations can inhibit plant absorption and even cause toxicity. This strategy limits fertilizer application, ensuring that even with high fertilizer application rates, plants are not adversely affected by excessive fertilizer.

[0139] In this embodiment, the specific method for formulating the fertilization strategy is:

[0140] When the maximum fertilizer application amount is greater than or equal to the required amount of all types of fertilizer elements, the total fertilizer application amount is calculated based on the required amount of each type of fertilizer element:

[0141]

[0142] Among them, Msf is the total amount of fertilizer, Mflx is the type of fertilizer amount, and according to the fertilizer element content Mf, the fertilizer amount is judged as the fertilizer element demand MFx or the fertilizer element supplement MB, Mflx ic is the amount of fertilizer applied for the icth fertilizer element, and nc is the number of fertilizer element types;

[0143] The method for calculating the fertilizer concentration of each fertilizer element type is:

[0144]

[0145] Among them, Cfn ic is the fertilizer concentration of the icth fertilizer element, Vsh is the amount of drip irrigation water for fertilization;

[0146] When the maximum fertilizer amount is less than the requirement of all types of fertilizer elements, the fertilizer amount is calculated based on the holding capacity;

[0147]

[0148] Among them, Msf is the total amount of fertilizer, RQf is the fertilizer element capacity,

[0149] The method for calculating the fertilizer concentration of each fertilizer element type is:

[0150]

[0151] Among them, Cfn ic is the fertilizer concentration of the icth fertilizer element, and Vsh is the amount of drip irrigation water for fertilization.

[0152] See also Figure 2 The present invention further provides a variable rate fertilization control method, which is obtained by executing the above-mentioned variable rate fertilization control system, and the specific steps include:

[0153] Step 1: Based on the soil characteristics of the area to be fertilized, a water diffusion model is established between the soil water diffusion range and the drip irrigation position, drip irrigation speed, and drip irrigation water volume during drip irrigation.

[0154] Step 2: Obtain the root growth range of the plants to be fertilized at different growth stages, determine the range of drip irrigation according to the distribution of groundwater layers in the soil characteristics, and calculate the volume of the drip irrigation range;

[0155] Step 3: Randomly select plants in the fertilization area as fertilizer element detection plants, conduct real-time concentration detection of fertilizer element types within the drip irrigation fertigation range where the fertilizer element detection plants are located, calculate the change rate of each type of fertilizer element content and set the fertilization cycle, and determine the plant's demand for each type of fertilizer element and the minimum absorption content within the fertilization cycle;

[0156] Step 4: Obtain the plant's tolerance to inorganic salt concentration and the average soil moisture, calculate the soil's fertilizer element capacity based on the soil's inorganic salt content, and calculate the maximum fertilizer amount based on the capacity and the volume of the drip irrigation range;

[0157] Step 5: Formulate a fertilization strategy based on the maximum fertilizer amount, the required amount of each type of fertilizer element and the minimum absorption content; calculate the fertilization drip irrigation rate and fertilization drip irrigation water volume based on the water diffusion model and the scope of drip irrigation; calculate the fertilizer concentration of each type of fertilizer element based on the fertilization drip irrigation water volume and fertilization strategy.

[0158] The above formulas are all dimensionless and calculated using numerical values. Their original dimension units are meters for length, kilograms for mass, seconds for time, liters for liquid volume, and moles per liter for concentration. The formulas are obtained by collecting a large amount of data and performing software simulation to obtain the most recent real situation. The preset parameters in the formulas are set by technicians in this field according to actual conditions.

[0159] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software depends on the specific application and design constraints of the technical solution.

[0160] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, and may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment as needed.

[0161] The above is only a specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be covered by the scope of protection of the present application.

Claims

1. A variable fertilization control system, characterized in that: include: A water diffusion model module is used to establish a water diffusion model between the soil water diffusion range and the drip irrigation position, drip irrigation speed, and drip irrigation water volume during drip irrigation according to the soil characteristics of the area to be fertilized; A drip irrigation range calculation module is used to obtain the root growth range of the plant to be fertilized at different growth stages, determine the range of drip irrigation according to the distribution of groundwater layers in the soil characteristics, and calculate the volume of the drip irrigation range; A fertilizer amount calculation module is used to randomly select plants in the area to be fertilized as fertilizer element detection plants, perform real-time concentration detection on the fertilizer element types within the drip irrigation fertigation range where the fertilizer element detection plants are located, calculate the rate of change of the content of each type of fertilizer element and the set fertilization cycle, and determine the plant's demand and minimum absorption content for each type of fertilizer element within the fertilization cycle; A fertilization safety module is used to obtain the plant's tolerance to inorganic salt concentration and the average soil moisture, calculate the soil's fertilizer element capacity based on the soil's inorganic salt content, and calculate the maximum fertilizer amount based on the capacity and the volume of the drip irrigation range; The concentration ratio module is used to formulate a fertilization strategy based on the maximum fertilizer amount, the demand for each type of fertilizer element and the minimum absorption content, calculate the fertilization drip irrigation speed and fertilization drip irrigation water volume based on the water diffusion model and the range of drip irrigation, and calculate the fertilizer concentration of each type of fertilizer element based on the fertilization drip irrigation water volume and fertilization strategy.

2. A variable fertilization control system according to claim 1, characterized in that: The soil characteristics include soil type, soil gap, soil moisture, distance to groundwater layer, and soil inorganic salt content; The specific process of establishing the water diffusion model is as follows: With the drip irrigation position during drip fertigation as the center, a three-dimensional coordinate system is established. Humidity sensors are placed equidistantly in four directions of the center position and at different depths. The coordinate positions of the sensor detection points are recorded. Drip irrigation is performed at the center position with different drip irrigation positions, drip irrigation water speeds, and drip irrigation water volumes. The humidity and coordinate positions of each detection point are recorded and combined with soil characteristics to form diffusion data. The drip irrigation position, drip irrigation water volume, and drip irrigation speed form water volume data. The diffusion data is used as the input of the neural network and the water volume data as the output to train the model and obtain a trained water diffusion model. The water diffusion model is based on a multi-layer perceptron, specifically including a hidden layer and an output layer.

3. A variable fertilization control system according to claim 1, characterized in that: The steps for calculating the volume of the fertigation range are: With the intersection of the plant and the ground as the center point, a three-dimensional coordinate system of the root coordinate range is established, and the distribution of the groundwater layer is mapped to the root coordinate system. The range of drip irrigation and fertigation is determined according to the coordinates of the root growth range and the water distribution coordinates. According to the range of drip irrigation and fertigation, the volume of the drip irrigation and fertigation range is calculated by the integral calculation method.

4. A variable fertilization control system according to claim 1, characterized in that: The fertilizer element content is calculated based on the real-time concentration of the fertilizer element and soil moisture; The method for determining the minimum absorption content is: The real-time changes of fertilizer element content in the historical fertilization cycle are counted to form a change curve, the lowest point of the fertilizer element content in each change curve is obtained, and the lowest value of the fertilizer element content of all tested plants is counted, which is the minimum absorption content.

5. A variable fertilization control system according to claim 4, characterized in that: The calculation method for the demand for fertilizer elements is: The formula for calculating the change rate of fertilizer element content is: Among them, Qf is the change rate of fertilizer element content, is the differential operation of the fertilizer element content Mf, Mf(t) is the fertilizer element content at time t, and Δt is the differential time period; Analyze the stability of the fertilizer element content based on the rate of change of the fertilizer element content. When the current fertilizer element content is in a stable state, compare it with the minimum absorption content to determine whether the current fertilizer element content is the minimum absorption content: When Qf=0, the current fertilizer element content is judged to be stable; When Mf=Czd, it is determined that the current fertilizer element content is the minimum absorption content.

6. A variable rate fertilization control system according to claim 5, characterized in that: When the current fertilizer element content is the minimum absorption content, the fertilizer element demand is calculated based on the fertilizer element content change rate, the minimum absorption content, the fertilizer element content and the volume of the drip fertigation range. The calculation formula is: MFx=α*ln(Qf max -1)*(Mf max -Czd)*V Among them, MFx is the demand for each type of fertilizer element, Qf max Mf is the maximum value of the change rate of fertilizer element content, max is the fertilizer element content at the maximum change rate of the fertilizer element content, Czd is the minimum absorption content, V is the volume of the drip fertigation range, and α is the correction coefficient; When Mf>Czd, it is judged that the current fertilizer element content is not the minimum absorption content; According to the change rate of fertilizer element content, the fertilizer element reserve content threshold is set, and fertilizer elements are supplemented according to the fertilizer element reserve content threshold. The calculation formula is: MB=(Mf MB -Czd)*V Among them, MB is the amount of fertilizer element supplement, Mf MB It is the reserve content threshold of fertilizer elements.

7. A variable rate fertilization control system according to claim 1, characterized in that: The fertilizer element holding capacity is calculated based on the average soil moisture, inorganic salt concentration tolerance concentration and soil inorganic salt content; The maximum fertilizer application amount is calculated based on the volume of the drip fertigation range and the fertilizer element holding capacity.

8. The variable rate fertilization control system according to claim 1, characterized in that: The specific method of formulating the fertilization strategy is: When the maximum fertilizer application amount is greater than or equal to the required amount of all types of fertilizer elements, the total fertilizer application amount is calculated based on the required amount of each type of fertilizer element: Among them, Msf is the total amount of fertilizer, Mflx is the type of fertilizer amount, and according to the fertilizer element content Mf, the fertilizer amount is judged as the fertilizer element demand MFx or the fertilizer element supplement MB, Mflx ic is the amount of fertilizer applied for the icth fertilizer element, and nc is the number of fertilizer element types; The method for calculating the fertilizer concentration of each fertilizer element type is: Among them, Cfn ic is the fertilizer concentration of the icth fertilizer element, Vsh is the amount of drip irrigation water for fertilization; When the maximum fertilizer amount is less than the requirement of all types of fertilizer elements, the fertilizer amount is calculated based on the holding capacity; Among them, Msf is the total amount of fertilizer, RQf is the fertilizer element capacity, The method for calculating the fertilizer concentration of each fertilizer element type is: Among them, Cfn ic is the fertilizer concentration of the icth fertilizer element, and Vsh is the amount of drip irrigation water for fertilization.

9. A variable fertilization control method, characterized in that: The detection method is obtained by executing a variable rate fertilization control system according to any one of claims 1 to 8, and the specific steps include: Step 1: Based on the soil characteristics of the area to be fertilized, a water diffusion model is established between the soil water diffusion range and the drip irrigation position, drip irrigation speed, and drip irrigation water volume during drip irrigation. Step 2: Obtain the root growth range of the plants to be fertilized at different growth stages, determine the range of drip irrigation according to the distribution of groundwater layers in the soil characteristics, and calculate the volume of the drip irrigation range; Step 3: Randomly select plants in the fertilization area as fertilizer element detection plants, conduct real-time concentration detection of fertilizer element types within the drip irrigation fertigation range where the fertilizer element detection plants are located, calculate the change rate of each type of fertilizer element content and set the fertilization cycle, and determine the plant's demand for each type of fertilizer element and the minimum absorption content within the fertilization cycle; Step 4: Obtain the plant's tolerance to inorganic salt concentration and the average soil moisture, calculate the soil's fertilizer element capacity based on the soil's inorganic salt content, and calculate the maximum fertilizer amount based on the capacity and the volume of the drip irrigation range; Step 5: Formulate a fertilization strategy based on the maximum fertilizer amount, the required amount of each type of fertilizer element and the minimum absorption content; calculate the fertilization drip irrigation rate and fertilization drip irrigation water volume based on the water diffusion model and the scope of drip irrigation; calculate the fertilizer concentration of each type of fertilizer element based on the fertilization drip irrigation water volume and fertilization strategy.

Images