CN-122022316-A - Potash fertilizer supply regulation and control method based on rhizosphere ion migration

CN122022316ACN 122022316 ACN122022316 ACN 122022316ACN-122022316-A

Abstract

The invention belongs to the technical field of crop fertilization control, and particularly relates to a potassium fertilizer supply regulation and control method based on rhizosphere ion migration. Firstly, constructing a reference potassium-demand intensity curve of crops based on historical data, and determining a potassium-demand time window and a reference potassium-supply time point. And analyzing the moisture state data acquired in real time through a moisture pulse identification criterion library, and identifying and quantifying a moisture pulse event. And then, accurately predicting an effective arrival time window of potassium ions under the pulse condition by utilizing a multiple linear regression model of the rhizosphere moisture pulse correction factor and a potassium ion rhizosphere migration model. And finally, calculating the time deviation between the arrival time window and the potassium-requiring time window, and dynamically correcting the reference potassium-supplying time point by using the deviation to realize the accurate synchronization of the fertilization time and the potassium-requiring absorption of crops, thereby effectively improving the utilization efficiency of potassium fertilizer.

Inventors

HAN CHUNXIAO
LI JIAHANG
HUANG LILI
JIANG YAN
LI SHOUJIANG
HOU JIANHUA
DENG XIAOYONG
ZHANG YIPENG
HE YONGFENG
Yuan Kaize
LIU JINGSEN
WANG JIALONG

Assignees

国投(四川)农业科技有限责任公司
国投新疆罗布泊钾盐有限责任公司

Dates

Publication Date: 20260512
Application Date: 20260128

Claims (10)

1. The potassium fertilizer supply regulation and control method based on rhizosphere ion migration is characterized by comprising the following steps of: fitting a standard potassium-demand intensity curve of crops according to soil basic index data, crop growth characteristic data and production data of a plurality of target fields in a plurality of historical years; Defining a continuous time period, in which the potassium demand intensity is more than or equal to a potassium demand intensity threshold value, in the reference potassium demand intensity curve as a potassium demand time window of crops; setting a plurality of potassium ion migration days before the starting time of the potassium-requiring time window as a reference potassium-supplying time point; collecting water state data of a target field, wherein the water state data comprises a water input quantity and a soil water content; the method comprises the steps of constructing a moisture pulse identification criterion library, wherein the moisture pulse identification criterion library comprises the criteria under each layered identification scene, and the criteria are that the change amount of the moisture content of soil is more than or equal to a preset proportion and the moisture input amount is more than or equal to a minimum threshold value of the moisture input amount; Screening out corresponding criteria from a water pulse identification criterion library according to the layering identification scene of the target field block; matching the moisture state data with a criterion, and if the matching is successful, judging that the target field has moisture pulse; under the condition that the moisture pulse occurs, establishing a multiple linear regression model of the rhizosphere moisture pulse correction factor according to the moisture pulse intensity, the moisture pulse duration and the moisture pulse influence depth of the target field block; calculating a rhizosphere water pulse correction factor of the target field according to the multiple linear regression model, and establishing a rhizosphere migration model of potassium ions by using the rhizosphere water pulse correction factor of the target field; calculating an effective arrival time window of potassium ions by using a rhizosphere migration model of the potassium ions; Calculating the time deviation between the effective rhizosphere arrival time window and the potassium-requiring time window of crops; correcting a reference potassium supply time point in a crop reference potassium supply strategy according to the time deviation; And adding potash fertilizer into the target field according to the corrected potassium supply time point.
2. The potassium fertilizer supply regulation method based on rhizosphere ion migration according to claim 1, wherein fitting a reference potassium demand intensity curve of crops comprises: Extracting target parameters meeting the requirement of not triggering the moisture-free pulse from a basic database; acquiring the average potassium demand intensity of crops in a target field at each growth period stage according to the target parameters; and fitting a standard potassium demand intensity curve of the crops in the whole growth period according to the average potassium demand intensity.
3. The method for regulating and controlling potassium fertilizer supply based on rhizosphere ion migration according to claim 2, wherein the target parameters comprise the start and stop time of each growth period stage, the potassium absorption amount of crops and the average biomass of single crops; Obtaining the average potassium demand intensity of crops in a target field in each growth period stage, comprising the following steps: calculating the stage duration of crops in each growth period stage in each historical year according to the start-stop time; calculating the potassium demand intensity of the crops in each growth period stage in each historical year according to the stage duration, the potassium absorption amount of the crops and the average biomass of the single crops, wherein the potassium demand intensity= (the potassium absorption amount of the crops is multiplied by 10 6 ) and/or (the average biomass of the crops is multiplied by the stage duration); for each growth stage, the potassium demand intensity for a plurality of historical years is averaged to obtain an average potassium demand intensity for each growth stage.
4. A potassium fertilizer supply control method based on rhizosphere ion migration according to claim 3, wherein the curve of the standard potassium demand intensity of crops in the whole growth period is fitted, comprising the steps of: According to the method for obtaining the average potassium demand intensity of crops in the target field at each growth period stage, obtaining the average potassium demand intensity of crops in the test field at each growth period stage; according to the average potassium demand intensity of crops in the test field at each growth period stage, calculating the average potassium demand intensity of crops in the target field at the midpoint of each growth period stage by an average method; linear interpolation is carried out by utilizing the average potassium demand intensity of crops at the midpoint time of adjacent growth period stages to obtain the average potassium demand intensity of crops in a target field at the start-stop time point of each growth period stage, and a potassium demand intensity database table is established; And (3) establishing a potassium-demand intensity fitting function of crops in the target field at each growth stage according to the potassium-demand intensity database table.
5. The potassium fertilizer supply regulation and control method based on rhizosphere ion migration as claimed in claim 1, wherein the construction of the water pulse identification criterion library comprises the following steps: Constructing a plurality of layered identification scenes of the water pulse according to the soil type, the slope and the irrigation mode; collecting effective historical data under each hierarchical recognition scene; extracting a minimum threshold value of the moisture input quantity triggering the moisture pulse from the effective historical data of each layering identification scene; the minimum threshold value of the change amount of the water content of the soil and the minimum threshold value of the water input amount are used as criteria, and the criteria are stored into a structured database according to the layered identification scene, so that a water pulse identification criterion library is obtained; Dividing all the moisture input quantities meeting the criteria in the historical effective data into a plurality of numerical intervals by using a quantile method, assigning a corresponding pulse intensity value for each numerical interval, and adding the pulse intensity value corresponding to each numerical interval assignment into a moisture pulse identification criterion library.
6. The potassium fertilizer supply control method based on rhizosphere ion migration of claim 5, wherein the step of quantifying the water pulse intensity, the water pulse duration and the water pulse influence depth of the output target field block comprises the steps of: judging a numerical value interval to which the moisture input amount in the moisture state data belongs, and taking a pulse intensity value corresponding to the numerical value interval to which the moisture input amount belongs as the moisture pulse intensity of the target field; taking the duration time of which the change amount of the water content of the soil is not less than the preset proportion as the water pulse duration time of the target field; And establishing a relation model between the response depth of the soil moisture content and the moisture input quantity through regression analysis, and acquiring the response depth of the soil moisture content corresponding to the moisture input quantity according to the relation model.
7. The potassium fertilizer supply regulation method based on rhizosphere ion migration according to claim 1, wherein a multiple linear regression model of rhizosphere moisture pulse correction factors is established, comprising the steps of: Determining the ratio of potassium ion migration efficiency in each experimental scene to potassium ion migration efficiency in a pulse-free scene by adopting an isotope tracking method to obtain an initial correction factor of rhizosphere water pulse in each experimental scene, wherein the experimental scene simultaneously comprises a plurality of influence factors of the rhizosphere water pulse correction factor, the plurality of influence factors comprise the combination of soil type, initial water content of the soil, water pulse intensity and water pulse duration, the initial correction factor is the ratio of potassium ion migration efficiency, the ratio of potassium ion migration efficiency = the potassium ion migration rate of the experimental scene +.; And establishing a multiple linear regression model of the rhizosphere water pulse correction factor and a plurality of influence factors.
8. The method for regulating and controlling potassium fertilizer supply based on rhizosphere ion migration of claim 1, wherein the rhizosphere migration model of potassium ions comprises the time when potassium ions reach the rhizosphere and the time when the concentration of potassium ions reaches a peak value; The time T 1 =T base ×Fw for potassium ions to reach the rhizosphere, wherein T base represents the basic arrival time of potassium ions from the potassium fertilizer application position to the rhizosphere under the pulse-free condition; the time T 2 =T 1 × (1+fw) at which the potassium ion concentration reached the peak.
9. The method for regulating and controlling potash fertilizer supply based on rhizosphere ion migration according to claim 1, wherein the time deviation comprises a time deviation amount and a time window position relation; calculating the time deviation between the effective rhizosphere arrival time window and the potassium-requiring time window of crops, comprising the following steps: calculating the length of the overlapping time period of the rhizosphere effective arrival time window and the potassium-requiring time window of crops, wherein the length of the overlapping time period = the ending time of the overlapping time period-the starting time of the overlapping time period; Calculating the time deviation amount by the length of the rhizosphere overlapping period, wherein the time deviation amount=the migration duration of potassium ions (1-the length of the rhizosphere overlapping period ≡the length of a potassium-requiring time window W k of crops); determining a time window positional relationship, comprising: If the whole effective rhizosphere arrival time window is positioned before the potassium-requiring time window of the crops, determining that potassium ions arrive at the rhizosphere in advance; if the rhizosphere effective arrival time is wholly located behind a potassium-requiring time window of crops, determining that potassium ions lag to reach the rhizosphere; if the time of the potassium ion concentration reaching the peak value is between the starting time of the potassium-requiring time window of the crop and the ending time of the potassium-requiring time window of the crop, judging that the rhizosphere effective reaching time window is partially overlapped with the potassium-requiring time window of the crop; If the time of potassium ion reaching the rhizosphere is between the starting time of the potassium-requiring time window of the crop and the ending time of the potassium-requiring time window of the crop, the effective rhizosphere reaching time window is determined to be partially overlapped with the potassium-requiring time window of the crop.
10. The potassium fertilizer supply regulation and control method based on rhizosphere ion migration according to claim 9, wherein the reference potassium supply time point in the crop reference potassium supply strategy is corrected according to the time deviation, comprising the following steps: acquiring the time point deviation correction amount of potassium ions according to the time deviation amount, the water pulse intensity and the soil type; correcting a reference potassium supply time point in a crop reference potassium supply strategy by utilizing the time point deviation correction quantity according to the time deviation direction; The method comprises the steps of establishing a multi-element nonlinear regression model taking the time deviation correction as a dependent variable and taking the time deviation, the water pulse intensity and the soil type as independent variables, wherein the multi-element nonlinear regression model can be expressed as DeltaT=k 1 ×△T w ×ln（I）+k 2 ×r+k 3 , wherein I is the water pulse intensity, r is the soil type coefficient, and k 1 、k 2 、k 3 is a fitting coefficient; correcting a reference potassium supply time point in a crop reference potassium supply strategy, comprising the following steps of: If the potassium ions reach the rhizosphere in advance or the starting time of the potassium-needed time window is less than the time of the potassium ions reaching the rhizosphere is less than the ending time of the potassium-needed time window, delaying the potassium supply time point, wherein the delayed potassium supply time point T=T 0 +△T;T 0 is taken as a reference potassium supply time point; If the potassium ion reaches the rhizosphere after the delay, or if the starting time of the potassium ion time window is less than the time of the potassium ion concentration reaching the peak value is less than the ending time of the potassium ion time window, the potassium supply time point is advanced, and the advanced potassium supply time point T=T 0 -DeltaT.

Description

Potash fertilizer supply regulation and control method based on rhizosphere ion migration Technical Field The invention belongs to the technical field of crop fertilization control, and particularly relates to a potassium fertilizer supply regulation and control method based on rhizosphere ion migration. Background Potassium is a macronutrient element essential for the growth and development of crops. For quality-oriented crops, the core requirement of potassium ion supply is not simply 'meeting the yield requirement', but 'accurately matching the potassium demand rhythm in the growing period of the crops', so that the effective supply of potassium ions in the key period of the crop quality is ensured. In actual field production, potassium ions mainly migrate in soil in a diffusion manner, the migration speed is low (the daily average migration distance is only a few millimeters), and the potassium ions are limited by factors such as soil adsorption-desorption balance, soil water content and the like. Particularly "water pulses" of rainfall, irrigation, etc. are key contributors to exacerbation of potassium imbalance. The water pulse can change the soil environment at the minute-hour level, remarkably improve the water content of the soil, enlarge the thickness of a rhizosphere water film and accelerate the diffusion and convection migration of potassium ions. At present, a potash fertilizer regulation strategy is generally a field scale averaging and experience dependence strategy, and a specific implementation mode comprises the steps of determining the total application amount according to a soil quick-acting potassium detection result before sowing, distributing fertilizer according to a fixed base fertilizer-topdressing ratio (such as a base dressing ratio of 6:4 and 5:5), and referring to a universal time node of a crop growing period (such as first topdressing 30 days after flue-cured tobacco transplanting) or recommended application amount released by regional agricultural technology popularization departments. The potassium fertilizer regulation strategy is established on three bottom layer assumptions, namely a macroscopic detection value (field mixed sampling detection) of quick-acting potassium of soil can truly reflect potassium ion accessibility of a root absorption area (rhizosphere micro-area) of crops, risks such as chloride ion accumulation and exceeding standard of soil salinity possibly generated after fertilization can be avoided through empirical rules such as 'high Wen Shifei', 'single use amount control', and the like, and potassium requirement rhythms of the same crop in the same growth period under different years and different meteorological conditions are consistent without dynamic regulation. According to the specific embodiment, the current potash fertilizer regulation and control strategy makes a fertilization plan by taking day or week as a time unit, and cannot respond to the rhizosphere potassium ion migration time sequence fluctuation of the minute-hour level under the driving of the water pulse. Specifically, under the drive of the water pulse, the high water content of the soil accelerates the migration of potassium ions, so that the time for the potassium ions to reach the rhizosphere is not matched with the potassium-requiring time of crops, the same fertilization dosage and the same fertilization position are enabled to show distinct effects under the condition of different water pulses, and the quality of crops is greatly fluctuated. Disclosure of Invention In order to solve the technical problems, the invention is realized by the following technical scheme: a potassium fertilizer supply regulation and control method based on rhizosphere ion migration comprises the following steps: fitting a standard potassium-demand intensity curve of crops according to soil basic index data, crop growth characteristic data and production data of a plurality of target fields in a plurality of historical years; Defining a continuous time period, in which the potassium demand intensity is more than or equal to a potassium demand intensity threshold value, in the reference potassium demand intensity curve as a potassium demand time window of crops; setting a plurality of potassium ion migration days before the starting time of the potassium-requiring time window as a reference potassium-supplying time point; collecting water state data of a target field, wherein the water state data comprises a water input quantity and a soil water content; the method comprises the steps of constructing a moisture pulse identification criterion library, wherein the moisture pulse identification criterion library comprises the criteria under each layered identification scene, and the criteria are that the change amount of the moisture content of soil is more than or equal to a preset proportion and the moisture input amount is more than or equal to a minimum threshold value of the moisture input amount;