KR102243902B1 - Heat stress measuring apparatus for plants and heat stress management system and method using the same - Google Patents

Abstract

According to the present invention, provided are a plant heat stress detection device, and a plant heat stress management system and a heat stress management method using the same. The plant heat stress detection device comprises: an incoming radiation amount measurement unit including a green sensor in which an internal temperature sensor is installed inside a green sphere made of plastics and installed between plants requiring measurement of heat stress, and an external temperature sensor which is installed in a space outside the green sensor; an emission radiation amount measurement unit for measuring the leaf temperature of a plant requiring the measurement of the heat stress; and a data analysis unit for calculating the amount of radiation coming into the plant by radiation by a difference between an internal temperature and an external temperature measured by the internal temperature sensor and the external temperature sensor, and calculating the amount of radiant energy emitted from the plant from a leaf temperature measured by the emission radiation amount measurement unit to calculate a thermal stress index by the ratio of the radiant energy emission amount calculated by the emission radiation measurement unit to the incoming radiation amount calculated by the incoming radiation measurement unit.

Description

TECHNICAL FIELD The heat stress measuring apparatus for plants and heat stress management system and method using the same.

The present invention relates to a technology for managing the thermal state of a plant, and more particularly, to a sensing device capable of measuring the thermal stress of a plant, and a management system and a management method for managing the thermal stress of a plant using the same.

Due to extreme weather, the productivity of crops is greatly deteriorating due to high temperature damage due to heatwave in summer and low temperature obstacles such as frost. In this way, it is important to understand physiological characteristics such as thermal characteristics of plants and interactions according to weather conditions in order to alleviate meteorological disasters and promote growth. In particular, the thermal characteristics of leaves are factors that affect photosynthesis efficiency and occurrence of apoptosis.

The thermal characteristics of leaves are determined by mechanisms such as energy inflow such as short-wave radiation and long-wave radiation, latent heat cooling by evaporation, geothermal heat cooling into the soil, sensible heat cooling by the atmosphere, and cooling through long-wave emission from plant leaves.

In particular, latent heat cooling in which energy introduced into plants is converted into heat within the plant and water vapor is discharged to the atmosphere through the evaporation process of plants is mainly affected by solar radiation, and other weather factors such as wind may be affected.

Therefore, since latent heat cooling is reduced under weak solar conditions, ground heat cooling, sensible heat cooling, and long-wave emission from leaves must be increased to balance the energy inflow and outflow of plants, and healthy crop growth can be promoted.

However, until now, various model equations such as the Penmann-Monteith equation for measuring evapotranspiration have been proposed to calculate the potential evapotranspiration, but there is no case of measuring only the transpiration of plants, and Bowen's ratio using the estimated latent and sensible heat. (Bowen ratio) is used to estimate continuous evapotranspiration, but when there is rainfall or when the difference between the temperature and the water vapor pressure in the vertical direction of the atmosphere is small, a large error occurs, so there are many restrictions on the estimation of the evapotranspiration of continuous plants. .

In order to analyze the thermal energy balance of plants, the moisture stress index is determined by investigating various latent heat emission characteristics under conditions that facilitate the discharge of water from plants under favorable weather conditions or poor weather conditions such as rainfall, or under conditions where evaporation is suppressed by applying vaseline, etc. Although it is being calculated and utilized, it is difficult to accurately diagnose the thermal characteristics of plants because there are many differences depending on the type of crop or growth stage.

In order to promote the growth of healthy crops in various weather conditions such as high temperature and low temperature, it is important to understand the thermal characteristics of plants, and continuous observation is required without time constraints.

KR 10-2010-0014558 A KR 10-1479685 B1 KR 10-2015-0060749 A KR 10-1927620 B1

Accordingly, the present invention can diagnose the heat stress of the plant regardless of time and place, observe the amount of radiant energy introduced during the cultivation environment, and evaluate the thermal state of the plant without evaluating the amount of transpiration, and do not use expensive radiation measuring equipment. Including a temperature-based radiation inflow measurement sensor that can check the total amount of short-wave radiation and long-wave radiation entering the plant without it, the degree of thermal stress of the plant (index) from the relationship between the long-wave emission amount from the plant and the total radiation amount through the plant temperature measurement. An object of the present invention is to provide a thermal stress sensing device capable of measuring.

In addition, the present invention provides a heat stress management method and a heat stress management system for plants capable of automatically managing high temperature damage or cold damage of plants by managing heat stress of plants in real time based on the measured heat stress level. It aims to do.

The device for detecting heat stress of a plant according to the present invention for solving the above problem,

An internal temperature sensor is installed inside a green sphere made of plastic, which is installed between plants requiring heat stress measurement, and a green sensor that measures the temperature inside the green sphere, and a green sensor installed in the space outside the green sensor Inflow radiation amount measuring unit having an external temperature sensor for measuring the temperature outside the sphere;

An emission radiation amount measuring unit that measures the leaf temperature of a plant that requires the measurement of the heat stress; And

The amount of radiation introduced into the plant by radiation is calculated by the difference between the temperature inside the green sphere and the temperature outside the green sphere measured by the internal temperature sensor and the external temperature sensor,

By calculating the amount of radiant energy emitted from the plant from the leaf temperature measured by the radiated radiation amount measuring unit,

And a data analysis unit for calculating a thermal stress index based on a ratio of the radiant energy emission amount calculated by the radiated radiation amount measuring unit to the radiant inflow amount calculated by the incoming radiation amount measuring unit.

The heat stress management system for plants according to the present invention,

A heat stress sensing device;

A temperature control device for controlling the outside temperature or leaf temperature, including a fine sprinkling device or a shading device, and

When the thermal stress index calculated by the thermal stress sensing device is out of a normal range, a system controller for operating the temperature control device is included.

Using the plant heat stress management system, the method of managing heat stress of plants,

Using the green sensor of the inflow radiation amount measurement unit, the external temperature sensor, and the emission radiation amount measurement unit, the temperature inside the green sphere, the temperature outside the green sphere, and the leaf temperature of the plant are measured in real time or periodically,

Substituting the difference between the temperature inside the green sphere and the temperature outside the green sphere measured by the green sensor into the calibration curve for the amount of radiation inflow, calculates the _{amount of inflow (E I)}

_{The emission radiation amount (E O} ) is calculated from the following equation 1 from the leaf temperature of the plant,

E _O = ε×σ × T ⁴ .......(Equation 1)

ε is emissivity coefficient, 0.95

σ is Stefan-Boltzmann coefficient (5.6704 × 10-8 W m ^-2 )

T is absolute temperature (273.15 + ℃)

_{The thermal stress index (S=E O} /E _I ) is calculated from the ratio of the radiated radiation amount to the calculated radiation inflow amount,

When the thermal stress index is in the range of 0.4 to 0.5, it is determined to be normal, and when the thermal stress index exceeds 0.4 to 0.5, the temperature control device is operated.

According to the present invention, it is possible to diagnose the thermal stress of the plant by measuring the amount of heat energy inflow and outflow at the plant cultivation site regardless of expensive equipment or time.

That is, there is an effect that thermal stress can be analyzed by measuring the energy flowing into the plant and the amount of energy emitted from the leaves of the plant by simply measuring the temperature.

In addition, by operating the temperature control device based on the heat stress index calculated in connection with the heat stress sensing device, there is an effect that it is possible to increase the efficiency of cultivation by preventing high temperature damage or cold damage to the plant.

1 is a block diagram showing the overall configuration of a thermal stress sensing device of a plant and a thermal management system using the same according to the present invention;
Figure 2 is a cross-sectional structure diagram showing the internal structure of the green sensor used in the thermal stress sensing device of the plant according to the present invention and an appearance photograph of the incoming radiation measurement unit;
3 is a calibration curve showing the relationship between the measured value of the amount of radiation inflow and the temperature inside the green sphere measured by the green sensor and the temperature outside the green sphere;
4 is a graph showing the relationship between the measured value of the amount of radiation inflow and the calculated value of the amount of radiation inflow calculated by the thermal stress sensing device according to the present invention;
5 is a graph showing a relationship between a measured value of latent heat emission and a thermal stress index value derived through a thermal stress sensing device according to the present invention;
6 is a photograph of the state of the plant according to the heat stress index calculated according to the present invention;
7 is a graph showing changes over time of the temperature outside the green sphere and the temperature inside the green sphere by the green sensor and the temperature outside the green sphere in a cooling condition at night;

Hereinafter, the present invention will be described in more detail with reference to the drawings.

1 is a block diagram showing the overall configuration of a thermal stress sensing device for plants and a thermal management system using the same according to the present invention, and FIG. 2 is an internal structure of a green sensor used in the thermal stress sensing device for plants according to the present invention. It is a cross-sectional structure diagram and a photograph of the appearance of the incoming radiation measurement unit.

The heat stress management system 1 for plants according to the present invention includes a heat stress sensing device 10, a temperature control device 20, and a system controller 30, as shown in FIG. 1.

Here, the thermal stress sensing device 10 is characterized in that it includes an inlet radiation amount measurement unit 11, an emission radiation amount measurement unit 13, and a data analysis unit 15.

The inflow radiation amount measuring unit 11 is a green sphere made of a plastic material as shown in FIG. 2 (hereinafter referred to as'green ball') installed between plants requiring measurement of heat stress (11A-a) And a green sensor 11A in which an internal temperature sensor 11A-b is installed in the interior of the unit, and an external temperature sensor 11B installed in the space outside of the green ball 11A-a.

The internal temperature sensor 11A-a measures the temperature inside the green ball corresponding to the internal temperature of the plant, and the external temperature sensor 11B measures the temperature outside the green ball corresponding to the temperature outside the plant, Based on the difference in temperature measured by these, the data analysis unit 15 to be described later calculates the amount of inflow due to radiation.

On the other hand, the radiated radiation amount measuring unit 13 measures the leaf temperature of plants that require the measurement of the thermal stress, and the data analysis unit 15 calculates the amount of radiant energy emitted from the plant by using this.

In the measurement of the leaf temperature, an infrared thermometer or a thermal image analyzer is used.

The operation of calculating the inlet radiation amount and the emitted radiation amount from the measured temperatures of the inlet radiation amount measurement unit 11 and the emission radiation amount measurement unit 13, and calculating the thermal stress index by the ratio of the calculated inlet radiation amount and the emission radiation amount is a data analysis unit. It will be performed in (15).

The temperature control device 20 includes a fine sprinkling device, a light shielding device, and the like.

The system control device 30 operates the thermal stress sensing device 10 through the control unit 31 to measure the incoming radiation amount and the emitted radiation amount to calculate a thermal stress index, and based on the calculated thermal stress index The temperature control device 20 is controlled to operate.

In addition, the control unit 31 may display data measured through an external device 40 such as a web of a PC or an app of a smartphone, or the thermal stress sensing device 10 or a temperature control device ( It can be configured to enable control of 20).

The data analysis unit 15 of the thermal stress sensing device 10 may be configured separately from the system control unit 30 to communicate in a wired/wireless manner, but preferably forms a part of the system control unit 30 It can be configured integrally.

When the heat stress sensing device 10 according to the present invention is described in detail, the green sensor 11A of the inflow radiation amount measuring unit 11 has similar radiation characteristics to the plant leaf as shown in FIG. 2, and flows into the plant. Plastic, especially acrylic spheres are used to reflect short-wave and long-wave radiation, and green balls (11A-a) are produced by painting green on the surface to match the radiation characteristics according to color. It is manufactured by inserting an internal temperature sensor 11A-b such as a thermocouple inside.

The green sensor manufactured in this way measures the temperature that rises inside the plant by radiation.

The size of the green ball 11A-a is not particularly limited, and the green ball shown in FIG. 2 and used in the test described below used a sphere having a diameter of 70 mm.

Depending on the diameter of the green ball (11A-a) to be used, there may be a slight difference in the relationship between the temperature inside the green sphere measured through the green sensor (11A) and the actual amount of radiation. In the case of changes such as, it is necessary to create a new calibration curve representing the relationship between temperature and total radiated inflow, which will be described later through an experiment.

Meanwhile, according to the present invention, at the same time as measuring the temperature inside the green ball, the outside temperature sensor 11B installed outside the green ball 11A-a is used to measure the temperature outside the green ball. The difference between the temperature of and inside the green ball measured through the green sensor 11A is defined as the total amount of energy introduced into the plant by radiation, that is, the rising temperature generated by the incoming radiation. Calculate the total amount.

In order to verify the correspondence between the temperature difference and the amount of incoming radiation, the total incoming radiation amount (short wave + long wave) actually measured through the separately installed long wave radiation sensor and the short wave radiation sensor, and the temperature between the inside temperature of the green ball and the outside temperature of the green ball. A calibration curve was prepared to know the relationship of the difference.

That is, the total incoming radiation amount (short wave + long wave) actually measured through the long-wave radiation sensor and the short-wave radiation sensor is set as the X-axis, and measured by the external temperature sensor 11B at the internal temperature of the green ball measured by the green sensor 11A. The calibration curve of FIG. 3 was created by using the value minus the external temperature (that is, the temperature difference) as the Y-axis.

3, the difference between the temperature inside the green ball measured using the green sensor 11A and the temperature outside the green ball measured using the external temperature sensor 11B, and the long-wave radiation sensor and the short-wave radiation sensor. Since the total amount of the measured radiant energy inflow has a constant proportional relationship, the temperature inside the green ball and the outside of the green ball by the inflow radiation amount measuring unit 11 of the thermal stress sensing device 10 according to the present invention using a green sensor By measuring the temperature, it is possible to confirm the suitability of calculating the incoming radiation.

In addition, from the calibration curve of FIG. 3 ^{, a relational expression of Y=0.012X-4.679 (r 2} =0.9740) was derived, and the temperature difference between the temperature inside the green ball of the green sensor 11A and the temperature outside the green ball was 1°C. When ascending, the total radiant inflow combined with the long wave and the short wave was calculated to be 83.3W/m².

Therefore, according to the present invention, the green sensor 11A using the green ball 11A-a and the external temperature sensor 11B without measuring the amount of incoming radiation by installing a short-wave radiation sensor or a long-wave radiation sensor at the plant cultivation site. ) To measure the temperature inside the green ball and outside the green ball, and substitute the difference into the calibration curve as shown in FIG. 3 to calculate the inflow radiation, so it is possible to measure the inflow radiation in real time with only temperature measurement. do.

In this way, using the internal temperature of the green ball measured by the green sensor 11A and the temperature outside the green ball measured by the external temperature sensor 11B, the inflow radiation amount calculated using the calibration curve of FIG. The calculated value (Y-axis) is shown in the graph of FIG. 4 in comparison to the measured inflow radiation amount (X-axis) measured using a short-wave radiation sensor and a long-wave radiation sensor.

As shown in Fig. 4, the amount of incoming radiation calculated using the green sensor 11A and the external temperature sensor 11B of the thermal stress sensing device 10 of the present invention is measured using a short-wave radiation sensor and a long-wave radiation sensor. It shows a linear proportional relationship with the measured value of inflow radiation, ^{and it can be confirmed that the relationship of Y=1.004X+12.90 (r 2} =0.9750) is established, so it is a simple thermometer measuring device without using a long-wave radiation sensor and a short-wave radiation sensor. It can be seen that the total amount of radiation can be calculated using only the green sensor and the external temperature sensor.

On the other hand, the emission radiation amount measurement unit 12 measures the amount of radiant energy emitted from the plant by irradiating the plant with an infrared thermometer or a thermal image analyzer to measure the leaf temperature.

The leaf temperature is measured, for example, by a method described later.

From plants (Chungoong colony) For observation of long-wave emission changes, a thermal imaging camera (TE-Q1 Pro, i3systems, Korea) with a resolution of 384 × 288 pixels was installed at a height of 2.5 m above the colony, and 4 crests planted in the center of the colony were selected for 10 minutes. The average temperature of the colony is observed by observing the temperature change of the leaves at intervals.

The amount of radiant energy emitted per unit area can be obtained by multiplying the measured leaf temperature by the Stefan-Boltzmann constant and the emissivity by the following (Equation 1).

E _O = ε×σ × T ⁴ .......(Equation 1)

ε is emissivity coefficient, 0.95

σ is Stefan-Boltzmann coefficient (5.6704 × 10 ^-8 W m ^-2 )

T is absolute temperature (273.15 + ℃)

The calculation of the radiation inflow amount E _I and the radiation emission amount E _O is performed by the data analysis unit 15.

In addition, the data analysis unit 15 calculates the thermal stress index (S) of the plant community by using _{the calculated total radiation inflow amount E I and the radiation emission amount.}

The heat stress index (S) is calculated by the ratio of the radiant energy emission amount (E _{O ) emitted from the plant community to the total radiation inflow amount (E I ).}

5 shows the relationship between the thus calculated thermal stress index (Y-axis) and the amount of latent heat released by transpiration (X-axis), which has been used as an index of heat stress of plants.

At this time, the amount of latent heat released by the transpiration was observed by making a lysimeter. Specifically, 4 load cells with a capacity of 250 kg having a resolution of 0.01% were installed, and a container in which plants (cheonggung) were planted was placed on the top of the load cell, and the change in weight of the cultivation container was measured. The load cell signal was directly connected to a data logger (CR1000, Campbell Scientific Inc., Logan, UT, USA) to measure the signal value every 1 minute, and then the average value of the observation data was recorded at 10 minute intervals. The reduction in weight measured at 10-minute intervals by the lysimeter was considered as an increase in production, and the amount of latent heat emission was calculated from this.

In a state in which the plant does not have heat stress, since evaporation is active and the amount of latent heat released by evaporation is high, it can be determined that there is no thermal stress of the plant as the value of the X-axis in FIG. 5 increases, and the thermal stress index at this time is 0.4 ~ It appears to be in the range of 0.5. On the other hand, when the latent heat release by evaporation is low, the thermal stress index exceeds 0.5 and reaches 0.9.

Based on this, according to the present invention, it is determined that the thermal stress index value (S=E ₀ /E _I ) expressed as the ratio of the amount of radiation inflow and the amount of radiation emitted is determined to be in a normal healthy plant state from 0.4 to 05. If it is higher than that, the plant It is judged to be under heating stress.

In addition, it is determined that the degree of thermal stress is higher as the value exceeds the normal range.

As described above, by using the thermal stress sensing device 10 of the present invention, it is possible to analyze the thermal stress by measuring the energy introduced into the plant and the amount of energy emitted from the leaf of the plant by simple temperature measurement.

Using the crest, the total radiant inflow and radiant emission are calculated from the temperature inside the green ball, the temperature outside the green ball, and the leaf temperature measured by the green sensor 11A, respectively, and thermal stress defined as the amount of radiated emission/the amount of radiated inflow. The index was calculated and shown in Table 1 below.

Green ball
Internal temperature
(℃) Green ball
Outside air temperature
(℃) Temperature difference
(℃) Radiation inflow
(W/㎥) Leaf temperature
(℃) Radiation Emission Amount
(W/㎥) Heat stress index 14.80 14.73 0.01 387.2 15.47 373.8 0.97 16.88 16.45 0.43 405.3 17.74 385.7 0.95 17.91 17.46 0.45 410.8 18.82 391.5 0.95 19.89 19.28 0.61 426.6 20.31 399.5 0.94 21.98 21.26 0.72 447.8 22.27 410.3 0.92 24.01 22.52 1.50 507.2 23.54 417.4 0.82 25.91 23.51 2.40 560.2 23.84 419.1 0.77 28.01 22.21 5.80 855.4 26.54 434.62 0.52 29.89 24.87 5.02 792.7 26.87 436.5 0.58 31.71 25.93 5.75 855.0 28.05 443.4 0.53 33.92 28.39 5.53 852.3 28.52 446.5 0.54 35.05 28.10 6.95 967.0 28.63 446.9 0.47 37.84 31.11 6.73 930.9 30.73 459.4 0.50

As can be seen in Table 1 above, the heat stress of a plant is not simply high when the outside temperature is high or low, and it is determined by changes in the radiant energy absorbed into the plant and the radiant energy emitted through the leaves. Using the thermal stress sensing device according to the invention, the green ball internal temperature corresponding to the temperature inside the plant and the temperature and leaf temperature outside the green ball corresponding to the temperature outside the plant are measured using a green sensor, respectively, and managed through it. Appears to be effective.

In addition, by using a medicinal crop, a medicinal crop that has a lot of damage due to suppression of evaporation under heat stress conditions such as high temperature and drought, the heat stress index is calculated using the heat stress detection device according to the present invention, and a little stress is performed in a healthy state. In the case of receiving and severely stressed, the conditions of the crops were respectively photographed and shown in FIG. 6.

As shown in FIG. 6, when it is determined that the heat stress is high as a result of the calculation of the heat stress index, it can be confirmed that the state of the plant is also markedly deteriorated, so that the heat stress sensing device according to the present invention is the actual heat stress of the plant. It can be seen that it can be usefully used to check the degree of.

Meanwhile, since the temperature of the surface of the plant is determined according to the change in the inflow amount of long-wave radiation at night without sunlight, the heat stress sensing device 10 according to the present invention may be used to diagnose cold damage to the plant.

That is, when long-wave radiation flows out to the upper atmosphere along with the temperature, the temperature of the surface of the plant, etc., decreases below the temperature. Since the green sensor 11A has similar physical properties to the leaves of the plant, the green sensor 11A The temperature inside the green ball measured by) changes similarly to the temperature of the leaf of the plant.

In FIG. 7, the temperature outside the green ball and the leaf temperature measured at 10-minute intervals in the night cooling condition using the thermal stress sensing device 10 of the present invention, and the temperature inside the green ball by the green sensor are shown for each time period.

As shown in FIG. 7, even if the temperature outside the green ball records the image, the leaf temperature and the temperature inside the plant (the temperature inside the green ball of the green sensor) may drop below zero and cause cold damage, so it is not the temperature outside the green ball. If the temperature inside the green ball measured by the green sensor goes below zero, it is necessary to operate the temperature control device 20 so as not to receive cold damage.

When explaining the action of the plant heat stress management system 1 according to the present invention consisting of the above configuration,

Under the control of the system control unit 30, the green sensor 11A and the external temperature sensor 11B constituting the incoming radiation amount measuring unit 11 are each time the temperature inside the plant (the temperature inside the green ball) and the temperature outside the plant. (The temperature outside the green ball) is measured, and the data analysis unit 15 calculates the total amount of radiation inflow from the difference in temperature.

In addition, at the same time as the measurement of the inflow radiation amount, the emission radiation amount measuring unit 13 made of an infrared thermometer or a thermal image temperature sensor measures the leaf temperature of the plant. The data analysis unit 15 calculates a radiant energy emission amount EO from the leaf temperature using (Equation 1).

E _O = ε×σ × T ⁴ .......(Equation 1)

ε is emissivity coefficient, 0.95

σ is Stefan-Boltzmann coefficient (5.6704 × 10-8 W m ^-2 )

T is absolute temperature (273.15 + ℃)

The data analysis unit 15 calculates a thermal stress index (S=E _O /E _I ) from the calculated _{amount of radiation inflow (E I} ) and emission amount (E _{O ).}

When the thermal stress index S is in the range of 0.4 to 0.5, it is determined as normal, and when the thermal stress index S is out of the range, the system controller 30 controls the temperature control device 20 to operate.

For example, when the thermal stress index exceeds 0.5, the temperature inside the green sensor is reduced by lowering the temperature or reducing the amount of radiant energy inflow by operating a fine sprinkling device or a shading device. As the surface temperature of the plant drops below zero, the surface temperature of the plant is also cooled to below zero. Therefore, take measures to prevent cooling damage using latent heat of condensation by operating a micro sprinkler at 0.2°C in consideration of the operating time of the device, or to prevent the radiation of the plant from leaking out. Control to operate the shading device as much as possible

Such a control action may be performed through a web, an app, etc. of the external device 40 using communication, or a control result or data may be displayed.

10: thermal stress detection device
11: Inflow radiation measurement unit
11A: Green sensor 11B: External temperature sensor
12: emission radiation amount measurement unit 13: data analysis unit
20: thermostat
30: system control unit
40: external device

Claims (4)

An internal temperature sensor is installed inside a green sphere made of plastic, which is installed between plants requiring heat stress measurement, and a green sensor that measures the temperature inside the green sphere, and a green sensor installed in the space outside the green sensor Inflow radiation amount measuring unit having an external temperature sensor for measuring the temperature outside the sphere;
An emission radiation amount measuring unit that measures the leaf temperature of a plant that requires the measurement of the heat stress; And
The amount of radiation introduced into the plant by radiation is calculated by the difference between the temperature inside the green sphere and the temperature outside the green sphere measured by the internal temperature sensor and the external temperature sensor,
By calculating the amount of radiant energy emitted from the plant from the leaf temperature measured by the radiated radiation amount measuring unit,
And a data analysis unit for calculating a thermal stress index based on a ratio of the radiant energy emission amount calculated by the radiated radiation amount measuring unit to the radiant inflow amount calculated by the incoming radiation amount measuring unit. A thermal stress sensing device according to claim 1;
A temperature control device for controlling external air temperature or leaf temperature, including a fine sprinkling device or a shading device, and
And a system controller configured to operate the temperature control device when the thermal stress index calculated by the thermal stress sensing device is out of a normal range. As a method of managing heat stress of a plant by using the heat stress management system of a plant according to claim 2,
Using the green sensor of the inflow radiation amount measurement unit, the external temperature sensor, and the emission radiation amount measurement unit, the temperature inside the green sphere, the temperature outside the green sphere, and the leaf temperature of the plant are measured in real time or periodically,
Substituting the difference between the temperature inside the green sphere and the temperature outside the green sphere measured by the green sensor into the calibration curve for the amount of radiation inflow, calculates the _{amount of inflow (E I)
The emission radiation amount (E O} ) is calculated from the following equation 1 from the leaf temperature of the plant,
E _O = ε×σ × T ⁴ .......(Equation 1)
ε is emissivity coefficient, 0.95
σ is Stefan-Boltzmann coefficient (5.6704 × 10-8 W m ^-2 )
T is absolute temperature (273.15 + ℃)
_{The thermal stress index (S=E O} /E _I ) is calculated from the ratio of the radiated radiation amount to the calculated radiation inflow amount,
When the thermal stress index is in the range of 0.4 to 0.5, it is determined to be normal, and when the thermal stress index is out of 0.4 to 0.5, a temperature control device is operated. The method of claim 3,
Regardless of the heat stress index, when the temperature inside the green sphere measured by the green sensor is less than or equal to a predetermined temperature, a temperature control device is operated.

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