CN113642269B - Precise irrigation method and irrigation system - Google Patents
Precise irrigation method and irrigation system Download PDFInfo
- Publication number
- CN113642269B CN113642269B CN202110871205.7A CN202110871205A CN113642269B CN 113642269 B CN113642269 B CN 113642269B CN 202110871205 A CN202110871205 A CN 202110871205A CN 113642269 B CN113642269 B CN 113642269B
- Authority
- CN
- China
- Prior art keywords
- soil
- sensor
- water
- crop
- irrigation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000003973 irrigation Methods 0.000 title claims abstract description 60
- 230000002262 irrigation Effects 0.000 title claims abstract description 60
- 238000000034 method Methods 0.000 title claims abstract description 19
- 239000002689 soil Substances 0.000 claims abstract description 128
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 95
- 238000011160 research Methods 0.000 claims abstract description 5
- 238000012272 crop production Methods 0.000 claims abstract description 4
- 239000000523 sample Substances 0.000 claims description 77
- 241000196324 Embryophyta Species 0.000 claims description 26
- 230000003750 conditioning effect Effects 0.000 claims description 15
- 230000008020 evaporation Effects 0.000 claims description 14
- 238000001704 evaporation Methods 0.000 claims description 14
- 230000005068 transpiration Effects 0.000 claims description 14
- 230000004907 flux Effects 0.000 claims description 9
- 239000003621 irrigation water Substances 0.000 claims description 9
- 230000007246 mechanism Effects 0.000 claims description 9
- 230000008595 infiltration Effects 0.000 claims description 8
- 238000001764 infiltration Methods 0.000 claims description 8
- 238000003780 insertion Methods 0.000 claims description 8
- 230000037431 insertion Effects 0.000 claims description 8
- 239000002352 surface water Substances 0.000 claims description 8
- 230000008635 plant growth Effects 0.000 claims description 7
- 238000010521 absorption reaction Methods 0.000 claims description 6
- 239000002344 surface layer Substances 0.000 claims description 6
- 230000008859 change Effects 0.000 claims description 5
- 238000005286 illumination Methods 0.000 claims description 5
- 238000012545 processing Methods 0.000 claims description 5
- 206010053759 Growth retardation Diseases 0.000 claims description 3
- 231100000001 growth retardation Toxicity 0.000 claims description 3
- 230000000979 retarding effect Effects 0.000 claims description 3
- 229920006395 saturated elastomer Polymers 0.000 claims description 3
- 238000003860 storage Methods 0.000 claims description 3
- 230000005012 migration Effects 0.000 abstract description 5
- 238000013508 migration Methods 0.000 abstract description 5
- 230000012010 growth Effects 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 230000006978 adaptation Effects 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 238000011065 in-situ storage Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000010025 steaming Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
- G06F30/28—Design optimisation, verification or simulation using fluid dynamics, e.g. using Navier-Stokes equations or computational fluid dynamics [CFD]
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01G—HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING
- A01G25/00—Watering gardens, fields, sports grounds or the like
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01G—HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING
- A01G25/00—Watering gardens, fields, sports grounds or the like
- A01G25/16—Control of watering
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01G—HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING
- A01G25/00—Watering gardens, fields, sports grounds or the like
- A01G25/16—Control of watering
- A01G25/167—Control by humidity of the soil itself or of devices simulating soil or of the atmosphere; Soil humidity sensors
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2111/00—Details relating to CAD techniques
- G06F2111/04—Constraint-based CAD
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2111/00—Details relating to CAD techniques
- G06F2111/06—Multi-objective optimisation, e.g. Pareto optimisation using simulated annealing [SA], ant colony algorithms or genetic algorithms [GA]
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2111/00—Details relating to CAD techniques
- G06F2111/10—Numerical modelling
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2113/00—Details relating to the application field
- G06F2113/08—Fluids
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
- G06F2119/14—Force analysis or force optimisation, e.g. static or dynamic forces
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A40/00—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production
- Y02A40/10—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production in agriculture
- Y02A40/22—Improving land use; Improving water use or availability; Controlling erosion
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Physics & Mathematics (AREA)
- Environmental Sciences (AREA)
- Water Supply & Treatment (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Geometry (AREA)
- Mathematical Physics (AREA)
- Pure & Applied Mathematics (AREA)
- Computer Hardware Design (AREA)
- Evolutionary Computation (AREA)
- Mathematical Analysis (AREA)
- General Engineering & Computer Science (AREA)
- Mathematical Optimization (AREA)
- Fluid Mechanics (AREA)
- Computing Systems (AREA)
- Algebra (AREA)
- Soil Sciences (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
The application relates to the field of agricultural irrigation, in particular to a precise irrigation method and system based on an optimal control algorithm. Comprises the steps of collecting relevant parameters of crop production; and constructing a hydrodynamic balance relation model oriented to the soil-plant-environment continuum based on an optimal control theory, and determining a research object, a state variable, a control variable and an external disturbance factor in the model by combining the acquired parameters. On the premise of not affecting the normal production of crops, the soil moisture information and the crop stem moisture information of different depth sections of the root zone of the crops are collected in a non-invasive manner; then, according to the water demand characteristics of different growth stages of crops, comprehensively considering the water migration rule of a soil-plant-environment system, comprehensively deciding by utilizing an optimal control theory to obtain an optimal irrigation index, and realizing the accurate irrigation of the crops by utilizing an irrigation system.
Description
Technical Field
The application relates to the field of agricultural irrigation, in particular to a precise irrigation method and system based on an optimal control algorithm.
Background
When the soil is in an unsaturated moisture state, the dominance of the soil to moisture migration by the plant is established on the competing relationship of soil water suction and plant root suction. The moisture migration is always in the dynamic balance of the two suction forces. Therefore, the irrigation decision is more scientific by comprehensively considering the moisture information of the soil-plant system. At present, research on accurate irrigation methods of crops at home and abroad is mostly based on selecting reasonable irrigation indexes, and the indexes are generally limited to water information of soil or a single plant object, so that the method has larger limitation. If soil moisture at a certain depth is measured or a plurality of soil sensors are placed at different depths of soil to obtain multi-point soil moisture, obviously the existing soil sensing technology tends to cause disturbance to the in-situ soil environment of crops, and the consistency of sensor probes is difficult to ensure; the common practice for obtaining plant moisture information is to measure leaf water potential, stem flow rate, etc. However, such methods generally have some effect on the normal growth of plants, and the obtained moisture information is not representative. Therefore, the soil-plant and environmental moisture information of the crops are obtained in a non-invasive manner, and the reasonable irrigation index is selected to be a basic premise for realizing accurate irrigation by combining the characteristics of the growth stage of the crops.
Disclosure of Invention
The application aims to overcome the defects in the prior art, and provides a precise irrigation method and an irrigation system, which are used for collecting soil moisture information and crop stem moisture information of different depth sections of a crop root zone in a non-invasive manner on the premise of not affecting the normal production of crops; then, according to the water demand characteristics of different growth stages of crops, comprehensively considering the water migration rule of a soil-plant-environment system, comprehensively deciding by utilizing an optimal control theory to obtain an optimal irrigation index, and realizing the accurate irrigation of the crops by utilizing an irrigation system.
The technical scheme of the application is as follows: the precise irrigation method comprises the following steps:
s1, collecting relevant parameters related to crop production, including microclimate information of farmlands, soil environment information, key moisture information of crops, surface water evaporation and infiltration information and irrigation water quantity;
s2, constructing a hydrodynamic balance relation model oriented to a soil-plant-environment continuum based on an optimal control theory, and determining a research object, a state variable, a control variable and external disturbance factors in the model by combining the parameters acquired in the step S1, wherein the state variable comprises surface water evaporation, infiltration, root zone soil water storage, crop stem flow, crop stem moisture and leaf transpiration, the control variable comprises irrigation water quantity, and the external disturbance factors comprise temperature, illumination, wind speed and rainfall values;
s3, establishing a relation between a model and parameters, determining an optimal irrigation decision and an optimal control objective function, wherein in a farmland which is covered by vegetation and is in an unsaturated soil water state, the hydrodynamic balance relation model of the soil-plant-environment continuum is as follows
Wherein θ (t) is soil water content, q (t) is three-dimensional water flow flux of soil water in x, y and z directions, S (t) is a source and sink item, the source and sink item depends on absorption of soil water by plant root system or leaf water transpiration and water evaporation of soil surface layer, wherein the absorption of soil water by plant root system or leaf water transpiration is represented by stem flow parameters, the stem flow parameters are detected by a stem flow sensor, the water evaporation of soil surface layer is detected by a transpiration instrument, and the source and sink item is the sum of the two;
respectively selecting points outside plant root zone and root zone, the coordinates of root zone point are (x 1 ,y 1 ,z 1 ) The coordinates of points outside the root zone are (x 1 ,y 1 ,z 2 ) Respectively placing soil moisture sensors at the two points to obtain two one-dimensional soil water equation sets under different depths
Wherein θz 1 、θz 2 For the soil moisture content, q, measured by two soil moisture sensors z1 、q z2 For the z-direction water flux, S (z 1 T) is a source sink item;
the switch decision function of the irrigation valve is
Wherein, threshold 1 And threshold 2 For z-direction water flux value q determined according to specific constraint conditions z The corresponding soil water content value is used for detecting the thetaz detected by the soil water content sensor in real time 1 Value and threshold 1 In contrast, θz 2 And threshold 2 In contrast, the on-off of the irrigation valve is precisely controlled according to the formula (3);
s4, selecting different objective functions or multiple objective functions according to actual requirements, wherein threshold in the formula (3) 1 And threshold 2 The joint solution of the system equations is determined depending on equation (2), the objective function and the specific constraints.
In the application, the limiting constraint conditions of the state variable and the control variable are as follows: valve flow Q has an upper bound; (ii) The soil water change takes the water content of plant growth retarding soil or plant wilting water content as a variable lower bound; (iii) The soil water change takes the water content of saturated soil or the maximum field water holding capacity as an upper limit;
wherein the critical point for plant growth retardation soil moisture content or plant wilting moisture content in (ii) is from plant stem moisture information.
In step S4, the objective function is to reduce the leakage of soil water below the root zone
Solving according to the formula (4) to obtain q for ensuring minimum soil water leakage z2 Value, q z2 The corresponding threshold is obtained by taking the formula (1) 2 Value of θz to be actually detected 2 And threshold 2 And (3) controlling whether to start or stop the irrigation valve according to the formula.
The application also comprises a precise irrigation system, wherein the precise irrigation system comprises a water pipe, an electromagnetic valve is arranged at a water inlet of the water pipe, a flowmeter is arranged at the electromagnetic valve, and the precise irrigation system further comprises a stem moisture sensor, a stem flow sensor, a three-depth soil moisture sensor, an electromagnetic valve, a lysimeter, a microclimate station and a main control box, wherein the stem moisture sensor and the stem flow sensor are fixed at crop stems, the three-depth soil moisture sensor is positioned in crop root zone soil, the lysimeter is positioned below the crop root zone soil, and the stem moisture sensor, the stem flow sensor, the three-depth soil moisture sensor, the electromagnetic valve, the flowmeter at the electromagnetic valve, the lysimeter and the microclimate station are respectively connected with the main control box;
the stem moisture sensor comprises a signal conditioning circuit board and a sensor probe supporting mechanism, wherein the signal conditioning circuit board is electrically connected with the sensor probe supporting mechanism, the sensor probe supporting mechanism comprises a crop stem fixing sliding block, a sliding support rod of the sliding block, a sensor probe supporting block and a sensor probe, the crop stem fixing sliding block and the sensor probe supporting block are oppositely arranged, the crop stem fixing sliding block and the sensor probe supporting block are in sliding connection through the sliding support rod of the sliding block, one end of the sliding support rod of the sliding block is fixedly connected with the sensor probe supporting block, and the crop stem fixing sliding block is sleeved on the outer side of the sliding support rod of the sliding block in a sliding manner;
the crop stalk fixing sliding block is internally provided with crop stalk jacks used for fixing crop stalks, one side of the sensor probe supporting block, facing the crop stalk fixing sliding block, is provided with a sensor probe, the sensor probe is arranged in the sensor probe supporting block in a sliding manner, the sensor probe is electrically connected with the signal conditioning circuit board, the sensor probe is in contact with the crop stalks, the sensor probe supporting block is internally provided with sensor supporting rod jacks, and the sensor supporting rod jacks are internally provided with inserted bars used for fixing the sensor probe supporting block;
the three-depth soil moisture sensor comprises a PVC connecting rod, wherein the head of the PVC connecting rod is provided with a PVC conical head, three groups of soil moisture sensor electrodes with different depths are arranged along the height direction of the PVC connecting rod at intervals, and the soil moisture sensor electrodes are respectively connected with a signal processing circuit through coaxial cables.
The crop stalks are positioned in the crop stalk insertion holes, stalk fastening screws are arranged at the crop stalk insertion holes, and the crop stalks are fixed in the crop stalk insertion holes by screwing the stalk fastening screws;
the crop stalk fixing slide block is further provided with a support rod fastening screw, the support rod fastening screw is located at a through hole in the crop stalk fixing slide block, the slide block slides on the support rod, and the support rod fastening screw is screwed to achieve fixed connection of the slide block sliding support rod and the crop stalk fixing slide block.
The signal conditioning circuit board is connected with the main controller through a data cable.
The outside of the sensor probe is provided with a probe guide rod, the sensor probe is arranged in the probe guide rod in a sliding way, and the probe guide rod is fixed in the jack of the sensor probe supporting block.
The beneficial effects of the application are as follows:
(1) Compared with the existing irrigation decision by relying on experience values or single indexes, the precise irrigation method and the irrigation system comprehensively consider the water migration rule of the soil-plant-environment system, and the optimal irrigation index is obtained by comprehensively deciding by utilizing the optimal control theory, so that the precise irrigation of crops is realized;
(2) On the premise of not affecting the normal production of crops, the stem moisture information of the crops is collected by using a stem moisture sensor in a non-invasive way, and the soil moisture of the soil in different depth sections is collected by using a three-depth soil moisture sensor in a non-invasive way;
(3) The stem moisture sensor, the stem flow sensor and the three-depth soil moisture sensor in the irrigation system are simple to install and detach, high in precision and relatively low in cost, not only can the irrigation precision be improved and water is saved, but also the high quality and high yield of crops can be guaranteed, and the method has very important significance for reducing the agricultural energy consumption, improving the economic benefit and promoting the sustainable and high-quality and high-efficiency development of agriculture.
Drawings
FIG. 1 is a schematic installation diagram of a precision irrigation system.
FIG. 2 is a schematic diagram of the structure of a stalk moisture sensor;
FIG. 3 is a schematic diagram of a three-depth soil moisture sensor;
in the figure: 1. a water pipe;
2. a stem moisture sensor; 201. a data cable; 202. a crop stalk fixing slide block; 203. the sliding block slides the supporting rod; 204. crop stalk insertion holes; 205. a stalk fastening screw; 206. a support rod fastening screw; 207. a sensor probe; 209. a sensor probe support block; 210. a sensor support rod jack; 211. a signal conditioning circuit board;
3. a stem flow sensor;
4. a three-depth soil moisture sensor; 401. a sensor circuit board mounting hole; 402. a coaxial cable; 403. a soil moisture sensor electrode of a first depth; 404. a second depth soil moisture sensor electrode; 405. a third depth soil moisture sensor electrode; 406. PVC cone head; 407. a PVC connecting rod;
5. an electromagnetic valve; 6. a steaming and infiltrating instrument; 7. a microclimate station; 8. and a main control box.
Detailed Description
In order that the above-recited objects, features and advantages of the present application will become more readily apparent, a more particular description of the application will be rendered by reference to the appended drawings.
In the following description, specific details are set forth in order to provide a thorough understanding of the present application. The present application may be embodied in many other forms than those herein described, and those skilled in the art may readily devise numerous other arrangements that do not depart from the spirit of the application. Therefore, the present application is not limited by the specific embodiments disclosed below.
The application comprises a precise irrigation method based on an optimal control theory, which comprises the following steps of.
And in the first step, the related parameters of crop production are collected, wherein the parameters comprise microclimate information of farmland, soil environment information, key moisture information of crops, surface water evaporation and infiltration information and irrigation water quantity.
As shown in fig. 1, microclimate information of the farmland, including temperature, illumination, wind speed, rainfall, etc. of the environment of the farmland, can be collected by the microclimate station 7. The diameter of the crop stalks is acquired in real time by the stalk moisture sensor 2, thereby obtaining the moisture information, such as the moisture content, of the crop stalks. The information of crop stem flow, leaf transpiration and the like is acquired in real time through the stem flow sensor 3. And collecting surface water evaporation and infiltration parameter information through a lysimeter 6. The irrigation water quantity is collected by the electromagnetic valve 5 and the flowmeter at the electromagnetic valve.
Secondly, constructing a hydrodynamic balance relation model oriented to a soil-plant-environment continuum based on an optimal control theory, and determining a research object, a state variable, a control variable and an external disturbance factor in the model by combining the data acquired in the first step; wherein the state variables comprise surface water evaporation, infiltration, soil water storage in root zone, crop stem flow, crop stem moisture and leaf transpiration; the control variables include irrigation water quantity; external disturbance factors include specific values of temperature, illumination, wind speed, rainfall, etc.
The defining constraints of the state variables and the control variables are as follows: valve flow Q has an upper bound; (ii) The soil water change takes the water content of plant growth retarding soil or plant wilting water content as a variable lower bound; (iii) The soil water variation is bounded by saturated soil water content or maximum field water holding capacity.
Wherein the critical point for plant growth retardation soil moisture content or plant wilting moisture content in (ii) is from plant stem moisture information.
Thirdly, establishing a relation between the model and the sensor data, and determining an optimal irrigation decision and an objective function of control. In a vegetation covered farmland in an unsaturated soil water state, the soil-plant-environment continuum has a hydrodynamic balance relationship model of
Wherein θ (t) is soil water content, q (t) is three-dimensional water flow flux of soil water in x, y and z directions, S (t) is a source and sink item, the source and sink item mainly depends on absorption of soil water by plant root system or leaf water transpiration and water evaporation of soil surface layer, wherein absorption of soil water by plant root system or leaf water transpiration is represented by stem flow parameters, the stem flow parameters are detected by a stem flow sensor, water evaporation of soil surface layer is detected by a transpiration instrument, and the source and sink item is the sum of the two.
Further, points are selected from the root zone and the outer part of the root zone of the plant in a certain place in the field, the point of the root zone is set as point A, and the coordinates are (x 1 ,y 1 ,z 1 ) Outside the root zone is the point B, the coordinates are (x 1 ,y 1 ,z 2 ) Point B may be located above or below point a. A soil moisture sensor is respectively arranged at the two points, and two one-dimensional soil water equation sets under different depths, namely a z-direction soil water equation set, can be approximately obtained in consideration of limited influence space of the moisture sensor
Wherein θz 1 、θz 2 For the soil moisture content, q, measured by two soil moisture sensors z1 、q z2 For the z-direction water flux, S (z 1 T) is a source sink term, θz 1 、θz 2 And S (z) 1 T) are observable variables.
As known from classical optimal control theory, whether the energy consumption is optimal, the time is optimal, and the energy consumption and the time are both optimal, a generalized optimal solution of an actual engineering problem is generally a switch decision function to be determined, namely:
wherein, threshold 1 And threshold 2 For z-direction water flux value q determined according to specific constraint conditions z The corresponding soil water content value is used for detecting the thetaz detected by the soil water content sensor in real time 1 Value and threshold 1 In contrast, θz 2 And threshold 2 And comparing, determining whether to open or stop the irrigation valve finally according to the comparison condition, namely determining the optimal irrigation time point for opening and closing the electromagnetic valve, so as to realize the accurate irrigation of the electromagnetic valve.
Fourth, according to the actual requirement, different objective functions or multiple objective functions can be selected, thresh in formula (3)old 1 And threshold 2 The joint solution of the system equations is determined depending on equation (2), the objective function and the specific constraints.
The application also comprises a precise irrigation system. As shown in fig. 1 to 3, the precise irrigation system comprises a water pipe 1, a stem moisture sensor 2, a stem flow sensor 3, a three-depth soil moisture sensor 4, an electromagnetic valve 5, a lysimeter 6, a microclimate station 7 and a main control box 8, wherein the stem of a plant to be tested is provided with the stem moisture sensor 2 and the stem flow sensor 3, in this embodiment, the stem moisture sensor 2 is located above the stem flow sensor 3, the stem moisture sensor 2 is used for collecting stem moisture information of crops, the stem flow sensor 3 is used for collecting stem flow information of crops, and key moisture information such as stem moisture, stem flow and leaf transpiration of crops can be obtained through the stem moisture sensor and the stem flow legend. The soil of the root zone of the plant to be detected is internally provided with a three-depth soil moisture sensor 4, and the three-depth soil moisture sensor 4 is used for collecting the soil moisture contents of different depths in the soil where the root zone of the crop is located. The soil top of plant to be measured is equipped with several water pipe 1, and water pipe 1's water inlet department is equipped with solenoid valve 5, and solenoid valve 5 department is equipped with the flowmeter, and solenoid valve 5 is used for the switching in the automatic control water pipe 1, can detect the flow of the interior irrigation water of water pipe 1 through the flowmeter simultaneously, through the switching time of control flow and solenoid valve 5, automatic control irrigation water yield. A lysimeter 6 is arranged below the root of the plant to be detected and is used for collecting the evaporation and infiltration amount of the surface water. The microclimate station 7 is used for collecting microclimate information of farmland, including temperature, illumination, wind speed, rainfall, etc. The stem moisture sensor 2, the stem flow sensor 3, the three-depth soil moisture sensor 4, the electromagnetic valve 5, the flowmeter at the electromagnetic valve, the lysimeter 6 and the microclimate station 7 are respectively connected with the main control box 8.
The stem moisture sensor collects the stem moisture information of the crop by measuring the diameter of the crop stem. As shown in fig. 2, the stalk moisture sensor 2 includes a signal conditioning circuit board 211 and a sensor probe supporting mechanism, the signal conditioning circuit board 211 is connected with the main controller 8 through a data cable 201, and the signal conditioning circuit board 211 is electrically connected with the sensor probe supporting mechanism. The sensor probe supporting mechanism comprises a crop stalk fixing slide block 202, a slide block sliding supporting rod 203, a sensor probe supporting block 209 and a sensor probe 207, wherein the crop stalk fixing slide block 202 and the sensor probe supporting block 209 are oppositely arranged, the crop stalk fixing slide block 202 and the sensor probe supporting block 209 are in sliding connection through the slide block sliding supporting rod 203, one end of the slide block sliding supporting rod 203 is fixedly connected with the sensor probe supporting block 209, and the crop stalk fixing slide block 202 is sleeved outside the slide block sliding supporting rod 203 in a sliding manner. In the sliding process of the sliding support rod 203, the distance between the sensor probe support block 209 and the crop stalk fixing sliding block 202 is adjustable, so that the sensor probe 207 is driven to move towards or away from the crop stalk to be detected.
A crop stalk jack 204 is arranged in the crop stalk fixing slider 202, the crop stalk is positioned in the crop stalk jack 204, a stalk fastening screw 205 is arranged at the crop stalk jack 204, and the crop stalk can be fixed in the crop stalk jack 204 by screwing the stalk fastening screw 205. Meanwhile, a support rod fastening screw 206 is further arranged on the crop stalk fixing slide block 202, the support rod fastening screw 206 is located at a through hole in the crop stalk fixing slide block 202 for enabling the slide block sliding support rod 203 to slide, and the support rod fastening screw 206 is screwed to achieve fixed connection between the slide block sliding support rod 203 and the crop stalk fixing slide block 202.
The sensor probe support block 209 is equipped with the sensor probe 207 towards the one side of crop stalk fixed slider 202, and the sensor probe 207 slides and sets up in the sensor probe support block 209, and in this embodiment, the outside of sensor probe 207 is equipped with the probe guide arm, and the sensor probe 207 slides and sets up in the probe guide arm, and the probe guide arm is fixed in the jack of sensor probe support block 209. The sensor probe is electrically connected with the signal conditioning circuit board 211, when the sensor probe 207 is propped against the crop stalks, the diameter parameters of the crop stalks are collected and transmitted to the signal conditioning circuit board 211, and finally transmitted to the main control box 8, and the moisture information of the crop stalks can be obtained according to the diameter of the crop stalks. The sensor probe supporting block 209 is also internally provided with a sensor supporting rod jack 210, the sensor supporting rod jack 210 is internally provided with an inserting rod, the inserting rod is fixed in the sensor supporting rod jack 210 by screwing a bolt, and the sensor probe supporting block 209 is fixed in soil by the inserting rod.
When the stalk moisture sensor 2 works, firstly, the sliding support rod 203 of the sliding block slides to drive the sensor probe support block 209 to move towards the direction of the crop stalk, and after the sensor probe support block 209 slides in place approximately, the support rod fastening screw 206 is screwed to fix the sliding support rod 203 in the crop stalk fixing sliding block 202; then, the position of the sensor probe 207 is adjusted to enable the sensor probe 207 to be in contact with the stalks of the crops to be detected, the sensor probe 207 is used for monitoring diameter parameters of the stalks of the crops to be detected in real time, the diameter parameters are transmitted to the main controller 8 through the signal conditioning circuit board 211, and moisture information of the stalks of the crops to be detected can be monitored in real time through the diameter parameters.
As shown in fig. 3, the three-depth soil moisture sensor 4 includes a PVC connecting rod 407, and a head of the PVC connecting rod 407 is provided with a PVC cone 406 to facilitate insertion of the PVC connecting rod 407 into soil. Three groups of soil moisture sensor electrodes are arranged at intervals along the height direction of the PVC connecting rod 407, namely an I depth soil moisture sensor electrode 403, an II depth soil moisture sensor electrode 404 and an III depth soil moisture sensor electrode 405 from top to bottom respectively, the three electrodes are used for monitoring the soil moisture content of different depths, and the soil moisture sensor electrodes are connected with a signal processing circuit through coaxial cables 402 respectively. During installation, the sensor circuit board mounting holes 401 are drilled at the mounting points of the soil moisture sensor electrodes, and the soil moisture sensor electrodes are inserted into the mounting holes, so that the soil moisture sensor electrodes and soil are ensured to be in reliable and tight contact, and the in-situ soil is hardly disturbed. In order to reduce the power consumption, the signal processing circuit can supply power through solar energy, and soil moisture sensor electrodes with different depths and the signal processing circuit thereof adopt time-sharing power-on to collect soil moisture parameters. In this embodiment, the data collected by the soil moisture sensor electrodes may be transmitted to the main control box 8 by wireless means.
The stem flow sensor 3 in the application can adopt a probe type stem flow sensor and a wrapped stem flow sensor, which are all in the prior art, so the structure is not repeated.
Example 1
In the embodiment, an objective function oriented to water-saving irrigation is provided as
J 1 The physical meaning of (2) is to reduce the leakage of soil water below the root zone as much as possible.
Solving according to the formula (4) to obtain q for ensuring minimum soil water leakage z2 Value, q z2 And is brought into the formula (1) to obtain the corresponding θz 2 And (3) determining whether to finally start or stop the irrigation valve according to the formula (3).
The precise irrigation method and the irrigation system provided by the application are described in detail. The principles and embodiments of the present application have been described herein with reference to specific examples, the description of which is intended only to facilitate an understanding of the method of the present application and its core ideas. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the application can be made without departing from the principles of the application and these modifications and adaptations are intended to be within the scope of the application as defined in the following claims. The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (7)
1. The precise irrigation method is characterized by comprising the following steps of:
s1, collecting relevant parameters related to crop production, including microclimate information of farmlands, soil environment information, key moisture information of crops, surface water evaporation and infiltration information and irrigation water quantity;
s2, constructing a hydrodynamic balance relation model oriented to a soil-plant-environment continuum based on an optimal control theory, and determining a research object, a state variable, a control variable and external disturbance factors in the model by combining the parameters acquired in the step S1, wherein the state variable comprises surface water evaporation, infiltration, root zone soil water storage, crop stem flow, crop stem moisture and leaf transpiration, the control variable comprises irrigation water quantity, and the external disturbance factors comprise temperature, illumination, wind speed and rainfall values;
s3, establishing a relation between a model and parameters, determining an optimal irrigation decision and an optimal control objective function, wherein in a farmland which is covered by vegetation and is in an unsaturated soil water state, a hydrodynamic balance relation model of the soil-plant-environment continuum is as follows
Wherein θ (t) is soil water content, q (t) is three-dimensional water flow flux of soil water in x, y and z directions, S (t) is a source and sink item, the source and sink item depends on absorption of soil water by plant root system or leaf water transpiration and water evaporation of soil surface layer, wherein the absorption of soil water by plant root system or leaf water transpiration is represented by stem flow parameters, the stem flow parameters are detected by a stem flow sensor, the water evaporation of soil surface layer is detected by a transpiration instrument, and the source and sink item is the sum of the two;
respectively selecting points outside plant root zone and root zone, setting the coordinates of root zone point as (x 1 ,y 1 ,z 1 ) The coordinates of points outside the root zone are (x 1 ,y 1 ,z 2 ) Respectively placing soil moisture sensors at the two points to obtain two one-dimensional soil water equation sets under different depths
Wherein θz 1 、θz 2 Two are twoSoil moisture content, q measured by individual soil moisture sensors z1 、q z2 For the z-direction water flux, S (z 1 T) is a source sink item;
the switch decision function of the irrigation valve is
Wherein, threshold 1 And threshold 2 For z-direction water flux value q determined according to specific constraint conditions z The corresponding soil water content value is used for detecting the thetaz detected by the soil water content sensor in real time 1 Value and threshold 1 In contrast, θz 2 And threshold 2 In contrast, the opening and closing of the irrigation valve is controlled according to the formula (3);
s4, selecting different objective functions or multiple objective functions according to actual requirements, wherein threshold in the formula (3) 1 And threshold 2 The joint solution of the system equations is determined depending on equation (2), the objective function and the specific constraints.
2. The precision irrigation method as recited in claim 1, wherein the defined constraints of the state variables and control variables are: valve flow Q has an upper bound; (ii) The soil water change takes the water content of plant growth retarding soil or plant wilting water content as a variable lower bound; (iii) The soil water change takes the water content of saturated soil or the maximum field water holding capacity as an upper limit;
wherein the critical point for plant growth retardation soil moisture content or plant wilting moisture content in (ii) is from plant stem moisture information.
3. The method according to claim 1, wherein in step S4, the objective function is an objective function for reducing leakage of soil water below the root zone
Solving according to the formula (4) to obtain q for ensuring minimum soil water leakage z2 Value, q z2 The corresponding threshold is obtained by taking the formula (1) 2 Value of θz to be actually detected 2 And threshold 2 And (3) controlling whether to start or stop the irrigation valve according to the formula.
4. The precise irrigation system utilizing the precise irrigation method of any one of claims 1-3 comprises a water pipe (1), wherein an electromagnetic valve (5) is arranged at a water inlet of the water pipe (1), and a flowmeter is arranged at the electromagnetic valve (5), and the precise irrigation system is characterized by further comprising a stem moisture sensor (2), a stem flow sensor (3), a three-depth soil moisture sensor (4), an electromagnetic valve (5), a lysimeter (6), a microclimate station (7) and a main control box (8), wherein the stem moisture sensor (2) and the stem flow sensor (3) are fixed at crop stems, the three-depth soil moisture sensor (4) is positioned in crop root zone soil, the lysimeter (6) is positioned below the crop root zone soil, and the stem moisture sensor (2), the stem flow sensor (3), the three-depth soil moisture sensor (4), the electromagnetic valve (5), the flowmeter at the electromagnetic valve, the lysimeter (6) and the microclimate station (7) are respectively connected with the main control box (8);
the stem moisture sensor (2) comprises a signal conditioning circuit board (211) and a sensor probe supporting mechanism, the signal conditioning circuit board (211) is electrically connected with the sensor probe supporting mechanism, the sensor probe supporting mechanism comprises a crop stem fixing sliding block (202), a sliding block sliding supporting rod (203), a sensor probe supporting block (209) and a sensor probe (207), the crop stem fixing sliding block (202) and the sensor probe supporting block (209) are oppositely arranged, the crop stem fixing sliding block (202) and the sensor probe supporting block (209) are in sliding connection through the sliding block sliding supporting rod (203), one end of the sliding block sliding supporting rod (203) is fixedly connected with the sensor probe supporting block (209), and the crop stem fixing sliding block (202) is sleeved on the outer side of the sliding block sliding supporting rod (203) in a sliding manner;
crop stalk jack (204) for fixing crop stalk is arranged in the crop stalk fixing slide block (202), sensor probe (207) is arranged on one side of the sensor probe supporting block (209) facing the crop stalk fixing slide block (202), the sensor probe (207) is arranged in the sensor probe supporting block (209) in a sliding mode, the sensor probe is electrically connected with the signal conditioning circuit board (211), the sensor probe (207) is in contact with the crop stalk, sensor support rod jack (210) is further arranged in the sensor probe supporting block (209), and inserted bars for fixing the sensor probe supporting block are arranged in the sensor support rod jack (210);
the three-depth soil moisture sensor (4) comprises a PVC connecting rod (407), wherein the head of the PVC connecting rod (407) is provided with a PVC conical head (406), three groups of soil moisture sensor electrodes with different depths are arranged at intervals along the height direction of the PVC connecting rod (407), and the soil moisture sensor electrodes are connected with a signal processing circuit through coaxial cables (402) respectively.
5. The precise irrigation system according to claim 4, wherein the crop stalks are positioned in crop stalk insertion holes (204), stalk fastening screws (205) are arranged at the crop stalk insertion holes (204), and the crop stalks are fixed in the crop stalk insertion holes (204) by screwing the stalk fastening screws (205);
the crop stalk fixing slide block (202) is further provided with a support rod fastening screw (206), the support rod fastening screw (206) is located at a through hole in the crop stalk fixing slide block (202) for enabling the slide block to slide, and the support rod fastening screw (206) is screwed, so that the fixed connection of the slide block sliding support rod (203) and the crop stalk fixing slide block (202) is achieved.
6. The precision irrigation system as recited in claim 4, wherein the signal conditioning circuit board (211) is connected to the master controller (8) by a data cable (201).
7. The precision irrigation system as recited in claim 4, wherein a probe guide rod is provided on an outer side of the sensor probe (207), the sensor probe (207) is slidably disposed within the probe guide rod, and the probe guide rod is secured within a receptacle of the sensor probe support block (209).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110871205.7A CN113642269B (en) | 2021-07-30 | 2021-07-30 | Precise irrigation method and irrigation system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110871205.7A CN113642269B (en) | 2021-07-30 | 2021-07-30 | Precise irrigation method and irrigation system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113642269A CN113642269A (en) | 2021-11-12 |
| CN113642269B true CN113642269B (en) | 2023-11-14 |
Family
ID=78419221
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110871205.7A Active CN113642269B (en) | 2021-07-30 | 2021-07-30 | Precise irrigation method and irrigation system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113642269B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114680029B (en) * | 2022-02-17 | 2023-05-16 | 广东省科学院广州地理研究所 | Irrigation method, device, equipment and storage medium based on soil and crop root system |
| CN114885702B (en) * | 2022-05-25 | 2023-05-26 | 广州大学 | Crop and soil monitoring and root system data collection system for layered irrigation |
| CN117296689B (en) * | 2023-11-17 | 2024-04-09 | 锦玉电力科技有限公司 | Energy-saving irrigation method and system based on well electricity double control |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102726273A (en) * | 2012-06-15 | 2012-10-17 | 中农先飞（北京）农业工程技术有限公司 | Decision-making method for soil moisture monitoring and intelligent irrigation of root zone of crop |
| EP3179319A1 (en) * | 2015-12-10 | 2017-06-14 | Sysman Progetti & Servizi S.r.l. | Method for irrigation planning and system for its implementation |
| CN107302875A (en) * | 2016-04-20 | 2017-10-31 | 青岛农业大学 | A kind of water-saving irrigation method based on the crucial moisture information of soil-plant system |
-
2021
- 2021-07-30 CN CN202110871205.7A patent/CN113642269B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102726273A (en) * | 2012-06-15 | 2012-10-17 | 中农先飞（北京）农业工程技术有限公司 | Decision-making method for soil moisture monitoring and intelligent irrigation of root zone of crop |
| EP3179319A1 (en) * | 2015-12-10 | 2017-06-14 | Sysman Progetti & Servizi S.r.l. | Method for irrigation planning and system for its implementation |
| CN107302875A (en) * | 2016-04-20 | 2017-10-31 | 青岛农业大学 | A kind of water-saving irrigation method based on the crucial moisture information of soil-plant system |
Non-Patent Citations (2)
| Title |
|---|
| 土壤-植物-大气连续体水分传输动力学及其应用;康绍忠;力学与实践;第15卷(第1期);第11-19页 * |
| 基于模糊控制理论的温室茶树灌溉控制策略研究;韩沙等;陕西农业科学;第67卷(第5期);第65-70页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113642269A (en) | 2021-11-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113642269B (en) | Precise irrigation method and irrigation system | |
| CN102726273B (en) | Decision-making method for soil moisture monitoring and intelligent irrigation of root zone of crop | |
| CN205175456U (en) | Quick analyzer for soil moisture content | |
| CN113049750B (en) | Method and system for diagnosing water stress of plant based on high-flux stomata conductivity | |
| CN103293200B (en) | A kind of soil moisture distribution measurement system and measuring method | |
| CN111742825A (en) | Construction and application of farmland accurate irrigation control model | |
| CN108802105A (en) | A kind of section type soil moisture content monitor being adapted to agricultural irrigation | |
| CN105738597A (en) | Soil moisture detecting instrument for detecting deep soil humidity | |
| CN105353106A (en) | Soil water distribution measurement system and method with wireless transmission function | |
| CN112931167B (en) | Plant irrigation decision system and method | |
| CN111406606B (en) | Intelligent water-saving irrigation system and irrigation method considering rice crop growth period | |
| Hermawan et al. | A quick dielectric method to determine insitu soil water content for precision water use under sustainable agricultural practices | |
| CN106910022B (en) | Wheat colony lodging-resistant critical wind speed determination and calculation method | |
| Werner | Measuring soil moisture for irrigation water management | |
| CN109239027A (en) | A kind of plant physiology water deficiency diagnosis method and system | |
| CN215836322U (en) | Device for providing accurate irrigation of paddy field crops | |
| CN106771056A (en) | A kind of crop coefficient evaluation method based on Plant stress index | |
| CN206557030U (en) | A kind of the soil moisture content sensor and automatic irrigation system of real-time monitoring soil moisture content | |
| CN109030786A (en) | A kind of farmland irrigation water measuring device and measuring method | |
| CN111727767B (en) | Tea tree monitoring cultivation system | |
| CN107302875A (en) | A kind of water-saving irrigation method based on the crucial moisture information of soil-plant system | |
| CN208705326U (en) | A kind of farmland irrigation water measuring device | |
| NL2029818B1 (en) | Water-saving irrigation method based on critical moisture information of soil-plant system | |
| Sui | Use of soil moisture sensors for irrigation scheduling | |
| CN112730800A (en) | Online measuring method for field water holding capacity |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |