Non-destructive diagnosis of water status and intelligent water supplement method for haloxylon ammodendron plantation based on crown-air temperature difference

Abstract

The application discloses a kind of based on crown air temperature difference's Haloxylon ammodendron artificial forest water non-destructive diagnosis and wisdom water supplement method, belong to forestry irrigation technical technical field.The present application is aimed at traditional soil moisture monitoring low precision, leaf detection is destructive, irrigation blind water shortage and other problems, by infrared temperature sensor acquisition crown temperature, microclimate and soil parameters are observed synchronously, calculate crop water stress index, construct root zone soil moisture prediction model and determine diagnostic threshold, finally rely on intelligent control system realizes automatic accurate water supplement.The present application realizes non-contact, non-destructive, fast water stress diagnosis, avoids soil spatial heterogeneity and salt interference, improves monitoring accuracy and efficiency, can be timely and appropriately watered as needed, greatly saves water resources in arid areas, adapts Taklimakan Desert edge Haloxylon ammodendron artificial forest's management and precise irrigation.

Description

Technical Field

[0001] This invention relates to the field of forestry irrigation technology, and in particular to a non-destructive method for water diagnosis and intelligent water replenishment in Haloxylon ammodendron plantations based on crown temperature difference. Background Technology

[0002] Haloxylon ammodendron, a perennial shrub belonging to the genus Haloxylon in the family Chenopodiaceae, possesses extremely strong drought, salt, and wind erosion resistance, making it a major afforestation species for windbreak and sand-fixing shelterbelts in the arid northwest of my country. In extremely arid regions such as the Taklamakan Desert, artificial irrigation is necessary for Haloxylon ammodendron plantations for 3-5 years after planting. Only after its roots have penetrated deep into the groundwater level or deep, moist sand layers can it rely on natural water for survival. Therefore, scientific and rational irrigation is crucial for ensuring the survival and preservation rate of Haloxylon ammodendron plantations.

[0003] Currently, although drip irrigation and flood irrigation facilities are available in the plantation shelterbelts of Haloxylon ammodendron in arid areas, the determination of irrigation time and water quotas largely relies on experience, resulting in high randomness and widespread phenomena of "blind irrigation and excessive irrigation," leading to serious waste of already extremely scarce groundwater resources. How to achieve "timely and appropriate" intelligent water replenishment while ensuring the normal growth of trees is a pressing technical challenge in the field of desert ecological restoration and efficient water resource utilization.

[0004] Plant canopy temperature is a comprehensive indicator reflecting the water and heat exchange process between vegetation and the atmosphere. When plants are subjected to water stress, stomatal conductance decreases, transpiration cooling weakens, and canopy temperature rises. Since the 1960s, canopy temperature and canopy-air temperature difference (the difference between canopy temperature and air temperature) have been widely used to quantify the degree of plant water deficit and have gradually become a hot topic in plant water status diagnosis research. In recent years, the theoretical model of the Crop Water Stress Index (CWSI) based on the energy balance principle has been developed. This model calculates the baseline without water stress (dTll) and the baseline without transpiration (dTul) using the Penman-Monteith equation, thereby quantitatively assessing the degree of plant water stress.

[0005] However, existing moisture diagnostic technologies based on canopy temperature are mostly focused on crops (such as wheat, corn, and cotton) and some fruit trees, with very little research on their application in desert shrubs, especially Haloxylon ammodendron plantations. Furthermore, most existing technologies remain at the level of revealing the patterns of canopy temperature changes and their response to meteorological factors, and have not yet truly established a closed-loop smart irrigation technology system from "moisture diagnostics" to "automatic water replenishment."

[0006] In terms of water monitoring methods, traditional methods are mainly divided into two categories: one category uses soil moisture as the independent variable, such as soil moisture sensor methods, time-domain reflectometry, and oven-drying methods. These methods are limited by factors such as strong spatial heterogeneity of soil, significant salinity effects, and high sensor deployment costs, making it difficult to guarantee monitoring accuracy and representativeness in large areas of desert forests. The other category uses plant leaf physiological and biochemical parameters as indicators, such as measuring leaf water potential, relative water content, and photosynthetic rate. These methods require field sampling and indoor analysis, and have disadvantages such as being destructive, having poor timeliness, and being unable to achieve continuous automatic monitoring.

[0007] In summary, existing technologies lack a non-destructive, rapid, and accurate method for water diagnosis specifically targeting Haloxylon ammodendron plantations, and even more so, they lack a smart water replenishment technology system that can directly use the diagnostic results to guide automatic irrigation. Therefore, developing a non-destructive water diagnosis and smart water replenishment method for Haloxylon ammodendron plantations based on crown-temperature difference is of great significance for the ecological restoration of desert vegetation and the efficient utilization of water resources in arid regions. Summary of the Invention

[0008] The purpose of this invention is to provide a non-destructive diagnosis and intelligent water replenishment method for Haloxylon ammodendron plantations based on crown temperature difference, so as to achieve non-contact, non-destructive, and rapid water stress diagnosis, avoid interference from soil spatial heterogeneity and salinity, improve monitoring accuracy and efficiency, and enable timely and appropriate water replenishment as needed, thereby significantly saving water resources in arid areas.

[0009] To achieve the above objectives, this invention provides a non-destructive water diagnosis and intelligent water replenishment method for Haloxylon ammodendron plantations based on crown temperature difference, comprising the following steps:

[0010] S1. Temperature observation of the canopy layer of Haloxylon ammodendron plantation: The temperature of the canopy layer of Haloxylon ammodendron plantation is collected using an infrared temperature sensor, which is installed above the canopy.

[0011] S2. Micro-meteorological data observation: Deploy wind speed and direction sensors, air temperature and humidity sensors, total radiation sensors, net radiation sensors, soil heat flux sensors, and soil moisture sensors. All sensors are connected to the data acquisition unit to collect and store wind speed, wind direction, air temperature, air relative humidity, radiation, soil heat flux, and soil moisture data at preset frequencies.

[0012] S3. Calculation of crop water stress index based on crown temperature difference Baseline crown temperature difference under no water stress was calculated by observing the crown temperature difference and combining the energy balance equation with the Penman-Monteith equation. Baseline crown temperature difference under non-transpiration conditions A theoretical model of crop water stress index was obtained. ;

[0013] S4. Construct a root zone soil moisture prediction model: using the relative available water content (RAW) of the soil as the predicted value, Using micrometeorological parameters as independent variables, a soil moisture forecasting model based on the crown temperature difference in the root zone of Haloxylon ammodendron plantations was established to determine the critical crown temperature difference and critical crop water stress index at different growth stages.

[0014] S5. Smart irrigation for Haloxylon ammodendron plantations: Based on the critical crown temperature difference and the critical crop water stress index, the intelligent control system automatically triggers irrigation equipment to complete the timely and appropriate water replenishment as needed.

[0015] Preferably, in S1, the infrared temperature sensor is an Apogee SI-111 model with a field of view of 22° half angle, a temperature measurement accuracy of ±0.2℃, and a temperature measurement range of -10℃ to 65℃, and is installed 50cm above the canopy of the closed forest stand.

[0016] Preferably, the soil moisture sensor in S2 is an EC-5 model, buried in the soil at depths of 5, 10, 20, 30, 50, 80, 100, 150, and 300 cm on one side of the vegetation roots; the soil heat flux sensor is an HFT-3 model, buried in the 5 cm soil layer; and the data acquisition device is a CR1000 model, which collects data once per minute and stores a set of average data every 10 minutes.

[0017] Preferably, S2 also includes a soil moisture calibration step: every ten days, the soil moisture at depths of 5, 10, and 20 cm around the vegetation is measured using the ring cutter method, with an additional calibration observation after rain.

[0018] Preferably, in S3, the theoretical model of crop water stress index The calculation formula is:

[0019] (1)

[0020] in, The observed crown temperature difference, in °C; The baseline crown temperature difference under no-moisture stress is expressed in °C. The baseline crown temperature difference under non-transpiration conditions, in °C; The value range is 0-1.

[0021] Preferably, in S3, the baseline crown temperature difference under water stress-free conditions... Baseline crown temperature difference under no-transpiration conditions Calculate as follows:

[0022] The expression is obtained by assuming that the canopy resistance is under potential evapotranspiration conditions:

[0023] (2)

[0024] In the formula, Net radiation absorbed by plants G represents soil heat flux. ; For aerodynamic impedance, ; air density, ; The air heat capacity is taken as 1013. ; This is the constant of the wet and dry meter. ; The slope of the saturated water vapor pressure as a function of temperature. ; For canopy resistance under potential evapotranspiration conditions, The calculation formula is:

[0025] (3)

[0026] In the formula, The minimum porosity of the blade is taken as 90. ; The effective leaf area index is calculated as follows:

[0027] (4)

[0028] In the formula, Leaf area index;

[0029] The expression is obtained by assuming that the canopy resistance is infinite:

[0030] (5)

[0031] Aerodynamic impedance The calculation formula is:

[0032] (6)

[0033] in, For reference height, in meters (m); The zero-plane displacement is m; The roughness length is in meters (m). For wind speed, .

[0034] Preferably, in S4, the formula for calculating the relative effective water content (RAW) of the soil is:

[0035] (9)

[0036] Where SWC is soil moisture content and FC is field capacity.

[0037] Preferably, in S4, the root zone soil moisture prediction model is determined through regression analysis, specifically including:

[0038] (1) Full meteorological parameter model:

[0039] (10)

[0040] Where F represents the functional relationship obtained by fitting through multiple linear regression or nonlinear regression.

[0041] Net radiation absorbed by plants RH is relative humidity; WS is wind speed. ;

[0042] (2) Simplified model without meteorological data:

[0043] (11)

[0044] Where P is the functional relationship obtained by fitting through univariate regression analysis;

[0045] The specific expression of the model and the critical RAW values ​​for different growth stages were determined by regression analysis, and then the critical crown temperature difference dT and the critical crop water stress index were derived by reverse calculation. .

[0046] Preferably, in S5, the intelligent control system is powered by solar energy and automatically starts and stops the irrigation equipment according to the critical thresholds of different growth stages of the Haloxylon ammodendron plantation.

[0047] A non-destructive water diagnosis and intelligent water replenishment system for Haloxylon ammodendron plantations based on crown temperature difference, used in the above method, includes:

[0048] An infrared temperature sensor, mounted above the canopy of Haloxylon ammodendron, is used to continuously collect canopy temperature data.

[0049] The micro-meteorological sensor group includes wind speed and direction sensors, air temperature and humidity sensors, total radiation sensors, net radiation sensors, soil heat flux sensors, and soil moisture sensors.

[0050] The data acquisition unit is connected to the infrared temperature sensor and the micro-meteorological sensor group respectively, and is configured to calculate the crown temperature difference and crop water stress index, and establish a soil moisture forecasting model.

[0051] The intelligent controller is connected to the data acquisition unit and controls the start and stop of the irrigation equipment based on the relative effective water content of the soil output by the soil moisture forecasting model or the preset critical stress index.

[0052] The solar power unit provides power to all components.

[0053] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0054] 1. Non-destructive rapid diagnosis: Based on infrared temperature sensors to obtain canopy temperature, it does not require contact with plants or destructive sampling, and does not require field sampling and indoor analysis. It can achieve continuous monitoring and real-time diagnosis around the clock, avoiding the lag and destructiveness of traditional physiological and biochemical techniques.

[0055] 2. Accurate and reliable diagnosis: Using plant canopy temperature as the core indicator, it directly reflects the plant's transpiration state and water stress level, avoiding interference from the strong spatial heterogeneity of soil moisture and the obvious salt retention effect, and overcoming the shortcomings of traditional soil moisture monitoring such as low accuracy and high cost.

[0056] 3. Closed-loop intelligent irrigation: The crown temperature difference diagnostic model is linked with the intelligent controller to realize a complete technical closed loop of "sensing-diagnosis-decision-execution". Irrigation is automatically started and stopped according to the actual water needs of plants. Compared with experience-based or timed irrigation, it can significantly reduce ineffective water use and improve water resource utilization efficiency.

[0057] 4. High adaptability and easy to promote: It provides both full meteorological parameter models and simplified models that only rely on crown temperature difference. Users can flexibly choose according to meteorological data conditions. The model parameters can be calibrated locally through regression analysis, which is convenient for large-scale application in Haloxylon ammodendron plantations in arid areas.

[0058] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0059] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0060] Figure 1 This is a schematic diagram of the process for non-destructive diagnosis and intelligent water replenishment of Haloxylon ammodendron plantations based on crown temperature difference, according to an embodiment of the present invention.

[0061] Figure 2 This is a schematic diagram illustrating the observation of temperature and micrometeorological elements in the canopy of a Haloxylon ammodendron plantation according to an embodiment of the present invention.

[0062] Figure 3 This is a schematic diagram of the intelligent water replenishment control system according to an embodiment of the present invention; (a) is a solar power supply unit, and (b) is an intelligent control terminal and irrigation execution equipment. Detailed Implementation

[0063] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0064] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0065] Example

[0066] like Figure 1 As shown, the specific steps of the non-destructive water diagnosis and intelligent water replenishment method for Haloxylon ammodendron plantations based on crown temperature difference are as follows:

[0067] S1, Temperature observation of the canopy layer in Haloxylon ammodendron plantation

[0068] like Figure 2 As shown, an Apogee (SI-111 type) canopy infrared temperature sensor and a smart water replenishment technology system control system were deployed in the observation area. The infrared temperature sensor has a field of view of 22.5° and a temperature measurement accuracy of ±0.2℃. It is installed in a waterproof shell and mounted on a bracket 50 cm above the canopy of the closed forest stand for continuous collection of the canopy temperature of the Haloxylon ammodendron plantation.

[0069] S2: Micrometeorological data observation

[0070] Micro-meteorological observation sensors were deployed, including wind speed and direction sensors, air temperature and humidity sensors, total radiation sensors, net radiation sensors, soil heat flux sensors, and soil moisture sensors. The soil moisture sensors (EC-5 type) were installed in soil layers at depths of 5, 10, 20, 30, 50, 80, 100, 150, and 300 cm on one side of the vegetation roots. Two soil heat flux sensors (HFT-3 type) were installed in the 5 cm soil layer.

[0071] All the instruments mentioned above are connected to the CR1000 data acquisition unit, which collects data once per minute and stores a set of average data every 10 minutes.

[0072] To calibrate the soil moisture sensor, soil moisture at depths of 5, 10, and 20 cm in three quadrats around the vegetation was measured every ten days using the ring cutter method, with an additional observation after rain.

[0073] S3. Calculation of Crop Water Stress Index Based on Crown Temperature Difference

[0074] Crop water stress index based on crown temperature difference calculate

[0075] (1)

[0076] In equation (1), The observed crown temperature difference (°C) is given. The lower baseline represents the crown temperature difference (°C) under conditions of no water stress. The upper baseline represents the crown temperature difference (°C) under no-transpiration conditions. Theoretically, The range of 0-1 represents the water condition from fully irrigated to no transpiration.

[0077] Based on different calculation methods for upper and lower baselines, this invention adopts the theoretical crop water stress index model. As .

[0078] Estimate using the Penman-Monteith equation and the energy balance equation and .in, The calculation method is as follows, which assumes that the canopy resistance is under potential evapotranspiration conditions:

[0079] (2)

[0080] In the formula, Net radiation absorbed by plants ( ), Soil heat flux ( ), Aerodynamic impedance ( ), air density ( ), air heat capacity (1013) ), The constant of the wet and dry surface ( ), The slope of saturated water vapor pressure as a function of temperature ( ), Canopy drag under potential evapotranspiration conditions ( The calculation formula is:

[0081] (3)

[0082] In the formula, Minimum porosity of the blade (90) ), The effective leaf area index is calculated as follows:

[0083] (4)

[0084] In the formula, Leaf area index (LAI) can be obtained by measuring leaf area using a leaf area instrument.

[0085] This is obtained by assuming that the canopy resistance is infinite, i.e. :

[0086] (5)

[0087] The calculation was performed using a semi-empirical formula proposed by Thom and Oliver, which is also the method recommended by Jackson et al., as follows:

[0088] (6)

[0089] in, Reference height (m) The zero-plane displacement is (m). Roughness length (m). Wind speed ( ).

[0090] The temperature difference between the canopy and dT and the net radiation absorbed by the plant canopy Plant canopy resistance Aerodynamic impedance It is closely related to the saturated vapor pressure difference (VPD). VPD can be reflected by the relative humidity (RH) and aerodynamic impedance. It is closely related to plant height and wind speed (WS). Plant canopy drag. It is mainly controlled by leaf surface resistance and stomatal resistance, and is directly related to the effective leaf area index (LAIe), stomatal characteristics (SC), and plant water potential. Plant water potential is closely related to the available soil water content (SWC). Therefore, plant canopy resistance... This can be represented by the effective leaf area index (LAIe), stomatal characteristics (SC), and available soil water content (SWC). This relationship can be expressed as:

[0091] (7)

[0092] For mature Haloxylon ammodendron plantations, the plant height H remains almost unchanged. Assuming that the stomatal water conduction capacity per unit leaf area is the same throughout the entire growth period of Haloxylon ammodendron, then the influence of a unit area of ​​Haloxylon ammodendron leaves on the canopy temperature difference is the same throughout the entire growth stage, and equation (7) can be simplified to:

[0093] (8)

[0094] S4. Construct a root zone soil moisture forecasting model

[0095] Field holding capacity (FC) is the upper limit of available water for plants and is usually used as the standard for calculating irrigation quotas. Soil moisture status is expressed using relative available water content (RAW).

[0096] (9)

[0097] Using soil relative water content (RAW) as the predicted value, and the crop water stress index based on canopy temperature difference as the predicted value. Net radiation absorbed by the plant canopy With relative humidity (RH) and wind speed (WS) as independent variables, a soil moisture prediction model based on the crown-temperature difference in Haloxylon ammodendron plantations can be established.

[0098] (10)

[0099] In the absence of meteorological data, the relative available soil water content (RAW) was used as the predicted value, and the crop water stress index based on the canopy temperature difference was used. Using the temperature difference between the canopy and the air as the independent variable, a soil moisture prediction model for the root zone of Haloxylon ammodendron plantations was established:

[0100] (11)

[0101] Since the exact relationship between equations (10) and (11) is still unclear, regression analysis was used to determine the expression of the soil moisture prediction model for the root zone of Haloxylon ammodendron plantations based on the canopy-temperature difference. Based on the critical effective soil water content at different growth stages, the critical canopy-temperature difference dT and crop water stress index at different stages were determined. This provides guidance for scientific irrigation in the arid areas on the edge of the Taklamakan Desert in Xinjiang Uygur Autonomous Region and for the diagnosis of water deficit in Haloxylon ammodendron plantations based on crown temperature difference.

[0102] S5, Smart Water Replenishment for Haloxylon ammodendron Plantations

[0103] Based on the critical canopy temperature difference and critical crop water stress index at different growth stages of Haloxylon ammodendron plantations, intelligent control technology is employed to automatically trigger irrigation equipment, achieving intelligent water replenishment for the plantations. The intelligent control system is solar-powered and automatically determines irrigation needs based on real-time monitoring data, enabling on-demand, timely, and appropriate water replenishment. Figure 3 As shown, (a) is a solar power supply unit, and (b) is an intelligent control terminal and irrigation execution equipment.

[0104] Through the above steps, a non-contact, rapid, and non-destructive diagnosis of the water status of Haloxylon ammodendron plantations on the edge of the Taklamakan Desert was achieved, and automatic water replenishment was carried out according to the actual water requirements of the plants.

[0105] The remaining technical features in the above embodiments can be flexibly selected by those skilled in the art to meet different specific practical needs according to actual circumstances. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims. In the above description, numerous specific details have been set forth to provide a thorough understanding of the present invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to implement the present invention. In other instances, to avoid obscuring the present invention, well-known techniques, such as specific construction details, operating conditions, and other technical conditions, have not been specifically described.

[0106] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A non-destructive water diagnosis and intelligent water replenishment method for Haloxylon ammodendron plantations based on crown-temperature difference, characterized in that, Includes the following steps: S1. Temperature observation of the canopy layer of Haloxylon ammodendron plantation: The temperature of the canopy layer of Haloxylon ammodendron plantation is collected using an infrared temperature sensor, which is installed above the canopy. S2. Micro-meteorological data observation: Deploy wind speed and direction sensors, air temperature and humidity sensors, total radiation sensors, net radiation sensors, soil heat flux sensors, and soil moisture sensors. All sensors are connected to the data acquisition unit to collect and store wind speed, wind direction, air temperature, air relative humidity, radiation, soil heat flux, and soil moisture data at preset frequencies. S3. Calculation of crop water stress index based on crown temperature difference Baseline crown temperature difference under no water stress was calculated by observing the crown temperature difference and combining the energy balance equation with the Penman-Monteith equation. Baseline crown temperature difference under non-transpiration conditions A theoretical model of crop water stress index was obtained. ; S4. Construct a root zone soil moisture prediction model: using the relative available water content (RAW) of the soil as the predicted value, Using micrometeorological parameters as independent variables, a soil moisture forecasting model based on the crown temperature difference in the root zone of Haloxylon ammodendron plantations was established to determine the critical crown temperature difference and critical crop water stress index at different growth stages. S5. Smart irrigation for Haloxylon ammodendron plantations: Based on the critical crown temperature difference and the critical crop water stress index, the intelligent control system automatically triggers irrigation equipment to complete the timely and appropriate water replenishment as needed.

2. The method for non-destructive water diagnosis and intelligent water replenishment of Haloxylon ammodendron plantations based on crown temperature difference according to claim 1, characterized in that: In S1, the infrared temperature sensor is an Apogee SI-111 model with a field of view of 22.5° and a temperature measurement accuracy of [missing information]. 0.2℃, temperature measurement range -10℃~65℃, set up 50cm above the canopy of a closed forest stand.

3. The method for non-destructive water diagnosis and intelligent water replenishment of Haloxylon ammodendron plantations based on crown temperature difference according to claim 1, characterized in that: The soil moisture sensor mentioned in S2 is an EC-5 model, buried in the soil at depths of 5, 10, 20, 30, 50, 80, 100, 150, and 300 cm on one side of the vegetation roots; the soil heat flux sensor is an HFT-3 model, buried in the soil layer at 5 cm depth; the data acquisition device is a CR1000 model, which collects data once per minute and stores a set of average data every 10 minutes.

4. The method for non-destructive water diagnosis and intelligent water replenishment of Haloxylon ammodendron plantations based on crown temperature difference according to claim 1, characterized in that: S2 also includes a soil moisture calibration step: every ten days, the soil moisture at depths of 5, 10, and 20 cm around the vegetation is measured using the ring cutter method, with an additional calibration observation after rain.

5. The method for non-destructive water diagnosis and intelligent water replenishment of Haloxylon ammodendron plantations based on crown temperature difference according to claim 1, characterized in that: In S3, the Crop Water Stress Index (CWSI) theoretical model dTt The calculation formula is: （1）； in, The observed crown temperature difference, in °C; The baseline crown temperature difference under no-moisture stress is expressed in °C. The baseline crown temperature difference under non-transpiration conditions, in °C; The value range is 0-1.

6. The method for non-destructive water diagnosis and intelligent water replenishment of Haloxylon ammodendron plantations based on crown temperature difference according to claim 5, characterized in that: In S3, the baseline crown temperature difference under no-moisture stress Baseline crown temperature difference under no-transpiration conditions Calculate as follows: The expression is obtained by assuming that the canopy resistance is under potential evapotranspiration conditions: （2）； In the formula, Net radiation absorbed by plants ; For soil heat flux, ; For aerodynamic impedance, ; air density, ; The air heat capacity is taken as 1013. ; This is the constant of the wet and dry meter. ; The slope of the saturated water vapor pressure as a function of temperature. ; For canopy resistance under potential evapotranspiration conditions, The calculation formula is: （3）； In the formula, The minimum porosity of the blade is taken as 90. ; The effective leaf area index is calculated as follows: （4）； In the formula, Leaf area index; The expression is obtained by assuming that the canopy resistance is infinite: （5）； Aerodynamic impedance The calculation formula is: （6）； in, For reference height, in meters (m); The zero-plane displacement is m; The roughness length is in meters (m). For wind speed, .

7. The method for non-destructive water diagnosis and intelligent water replenishment of Haloxylon ammodendron plantations based on crown temperature difference according to claim 1, characterized in that: In S4, the formula for calculating the relative available water content (RAW) of the soil is: （9）； Where SWC is soil moisture content and FC is field capacity.

8. The method for non-destructive water diagnosis and intelligent water replenishment of Haloxylon ammodendron plantations based on crown temperature difference according to claim 1, characterized in that: In S4, the root zone soil moisture prediction model is determined through regression analysis, specifically including: (1) Full meteorological parameter model: （10）； in, This refers to the functional relationship obtained through multiple linear regression or nonlinear regression. Net radiation absorbed by plants RH is relative humidity; WS is wind speed. ; (2) Simplified model without meteorological data: （11）； Where P is the functional relationship obtained by fitting through univariate regression analysis; The specific expression of the model and the critical RAW values ​​for different growth stages were determined by regression analysis, and then the critical crown temperature difference dT and the critical crop water stress index were derived by reverse calculation. .

9. The method for non-destructive water diagnosis and intelligent water replenishment of Haloxylon ammodendron plantations based on crown temperature difference according to claim 1, characterized in that: In S5, the intelligent control system is powered by solar energy and automatically starts and stops the irrigation equipment according to the critical thresholds of different growth stages of the Haloxylon ammodendron plantation.

10. A non-destructive water diagnosis and intelligent water replenishment system for Haloxylon ammodendron plantations based on crown temperature difference for implementing the method of any one of claims 1-9, characterized in that, include: An infrared temperature sensor, mounted above the canopy of Haloxylon ammodendron, is used to continuously collect canopy temperature data. The micro-meteorological sensor group includes wind speed and direction sensors, air temperature and humidity sensors, total radiation sensors, net radiation sensors, soil heat flux sensors, and soil moisture sensors. The data acquisition unit is connected to the infrared temperature sensor and the micro-meteorological sensor group respectively, and is configured to calculate the crown temperature difference and crop water stress index, and establish a soil moisture forecasting model. The intelligent controller is connected to the data acquisition unit and controls the start and stop of the irrigation equipment based on the relative effective water content of the soil output by the soil moisture forecasting model or the preset critical stress index. The solar power unit provides power to all components.

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