KR20210045253A - Irrigation system and method using water shortage diagnosis of crops - Google Patents

Abstract

The present invention relates to a system and method for performing irrigation by using water stress diagnosis of crops, capable of quantifying water stress of the crops. According to the present invention, the method for performing the irrigation by using the water stress diagnosis of the crops includes the steps of: generating weather information and measurement information; calculating an index value of water stress and an effective soil water content; and determining the irrigation by comparing the index value with a preset reference value of the water stress, and comparing the effective soil water content with a threshold value of the maximum allowable soil water deficit.

Description

Irrigation system and method using water stress diagnosis of crops {IRRIGATION SYSTEM AND METHOD USING WATER SHORTAGE DIAGNOSIS OF CROPS}

The present invention relates to an irrigation system and method using the water stress diagnosis of crops, and in particular, to a decision-making system and method for determining an appropriate irrigation timing and irrigation amount in connection with soil moisture information.

The conventional irrigation control method for cultivation of crops is a method of spraying water for a predetermined time every day or on a predetermined date. Appropriate irrigation management for crop cultivation means minimizing the use of water stress and excessive water on the crop, and putting only the amount necessary for crop growth at the right time and at the right time. Excessive irrigation more than necessary increases soil erosion and causes contamination of surface water and groundwater due to movement and leaching of water, while insufficient irrigation causes a problem of lowering the productivity and quality of cultivated crops.

Meanwhile, in the related art, irrigation was performed by manually operating an irrigation controller for irrigation, or setting the irrigation controller to irrigation for a predetermined time every day or at a fixed date interval. However, this irrigation control method is generally a method based on a grower's experience or a cultivation textbook, and proceeds regardless of the quality target of the crop or the actual moisture level of the soil, and thus it is difficult to contribute to the improvement of the quality of the cultivated product.

In this regard, conventional Korean Patent Publication No. 10-2012-0072826 is an irrigation control device using a soil moisture tensiometer, and information on soil moisture through a soil moisture tensiometer and a tension sensor that measures the moisture tension of the soil. It discloses a technology for performing irrigation based on.

However, when measuring the moisture tension of the soil, environmental control is performed using information considering only the external environmental conditions of the crop, and therefore, environmental control tailored to the condition of the crop cannot be performed. In other words, the current greenhouse control system evaluates whether the crop is sick, lack of moisture, photosynthesis, and transpiration during the growth process of the crop, and does not reflect this in the greenhouse environment control. .

Korean Patent Publication No. 10-2012-0072826

An object of the present invention is to provide a system and method for determining irrigation timing and irrigation amount by diagnosing crop moisture stress using leaf temperature information and meteorological information.

: Crop Water Stress Index)과 토양유효수분함량(

)를 산출하는 산출부; 및 상기 지수값과 기 설정된 수분스트레스의 기준값(

)을 비교하고, 상기 토양유효수분함량(

)과 상기 작물의 최대 토양수분허용 부족량(MAD: Maximum Allowable Deficit)의 임계 값과 비교하여 관개를 결정하는 제어부를 포함하는 작물의 수분스트레스 진단을 이용한 관개 시스템을 제공한다.In order to achieve the above object, the present invention is an irrigation system using a moisture stress diagnosis of a crop according to a ratio of the effective moisture content of the soil, including at least one of temperature, humidity, solar radiation, or wind speed of the atmosphere where the crop is located. A measurement unit that generates measurement information by measuring weather information and leaf temperature of the crop; The index value of the moisture stress of the crop by using the measurement information of a specific time period among the measurement information (

: Crop Water Stress Index) and effective soil moisture content (

A calculation unit that calculates ); And a reference value of the index value and a preset moisture stress (

), and the effective soil moisture content (

) And a control unit for determining irrigation by comparing with a threshold value of the maximum allowable soil moisture deficit (MAD) of the crop.

According to an embodiment, the measurement unit may include at least one of a thermal imaging camera, an infrared sensor, and a drone to measure the leaf temperature.

According to an embodiment, the thermal imaging camera may measure the leaf temperature by averaging the temperature and spatial variation of the outer part of the crop by using an RGB or infrared image.

: Crop Water Stress Index)은, 상기 엽온과 상기 작물이 위치한 대기 온도 간의 차이의 상한선 및 하한선을 이용하여 산출될 수 있다.According to an embodiment, the index value of the moisture stress of the crop (

: Crop Water Stress Index) may be calculated using the upper and lower limits of the difference between the leaf temperature and the atmospheric temperature in which the crop is located.

: Crop Water Stress Index)이 기 설정된 수분스트레스의 기준 값(

)을 초과하고, 상기 토양유효수분함량(

)이 상기 작물의 최대 토양수분허용 부족량(MAD: Maximum Allowable Deficit)의 임계 값 미만인 경우, 관개 시작을 결정할 수 있다. 상기 임계 값은, 80% 미만으로 설정될 수 있다.Depending on the embodiment, the control unit, the index value of the moisture stress of the crop (

: Crop Water Stress Index) is the standard value of moisture stress (

), and the effective soil moisture content (

) Is less than the threshold value of the maximum allowable soil moisture deficit (MAD) of the crop, it is possible to determine the start of irrigation. The threshold value may be set to less than 80%.

: Crop Water Stress Index)과 토양유효수분함량(

)를 산출하는 단계; 및 상기 산출부의 결과를 통해 제어부에서 상기 지수 값과 기 설정된 수분스트레스의 기준 값(

)을 비교하고, 상기 토양유효수분함량(

)과 상기 작물의 최대 토양수분허용 부족량(MAD: Maximum Allowable Deficit)의 임계 값과 비교하여 관개를 결정하는 단계를 포함하는 작물의 수분스트레스 진단을 이용한 관개 방법을 제공하는 것을 다른 특징으로 한다.In addition, the present invention, in the irrigation method using the water stress diagnosis of the crop according to the ratio of the effective moisture content of the soil, the weather information including at least one of temperature, humidity, solar radiation, or wind speed of the atmosphere where the crop is located, and the Generating measurement information by measuring the leaf temperature of the crop in a measuring unit; The index value of the moisture stress of the crop in the calculation unit by using the measurement information of a specific time period among the measurement information (

: Crop Water Stress Index) and effective soil moisture content (

Calculating ); And a reference value of the index value and a preset moisture stress in the control unit through the result of the calculation unit (

), and the effective soil moisture content (

It is another feature to provide an irrigation method using the diagnosis of moisture stress of a crop comprising the step of determining irrigation by comparing with) and a threshold value of the maximum allowable deficit (MAD) of the crop.

According to an embodiment, the measurement information may be calculated at a predetermined specific time period, and may be measured above a predetermined temperature or below a humidity.

)은, 상기 작물의 기 설정된 재배기간 동안 상기 지수 값(

)의 평균 값으로 설정될 수 있다.According to an embodiment, the reference value of the moisture stress (

) Is the index value (

) Can be set as an average value.

In addition, the present invention is another feature of providing a computer-readable recording medium in which a program for executing any one of the above-described methods is recorded.

According to the present invention having the configuration as described above, there is an advantage that it is possible to quantify crop moisture stress using non-destructive infrared imaging technology.

In addition, the present invention has the advantage of minimizing damage and promoting drought countermeasures by applying appropriate water management technology development.

In addition, the present invention has the advantage of bringing about improvement in farm production efficiency and income increase according to the continuous provision of the basis for cultivation of field crops.

1 shows a flow chart of the irrigation method using the water stress diagnosis of the crop of the present invention.
Figure 2 shows the appearance of a program implementing the crop moisture stress index (CWSI) calculation method according to an embodiment of the present invention.
3 shows a state of measuring leaf temperature of a crop according to an embodiment of the present invention.
4 shows a state of measuring leaf temperature of a crop through separation between infrared images using a thermal imaging camera according to an embodiment of the present invention.
5 shows changes in leaf temperature before and after irrigation according to an embodiment of the present invention.
6 shows a change in CWSI due to a change in soil moisture content according to an embodiment of the present invention.
7 shows a correlation between soil moisture content and CWSI according to an embodiment of the present invention.
8 shows a comparison between predicted leaf temperature and measured leaf temperature using meteorological data according to an embodiment of the present invention.
9 shows the results of analysis of fruit characteristics according to an embodiment of the present invention.

The terms used in the present specification will be briefly described, and the present invention will be described in detail.

Terms used in the present invention have selected general terms that are currently widely used as possible while taking functions of the present invention into consideration, but this may vary according to the intention or precedent of a technician working in the field, the emergence of new technologies, and the like. In addition, in certain cases, there are terms arbitrarily selected by the applicant, and in this case, the meaning of the terms will be described in detail in the description of the corresponding invention. Therefore, the terms used in the present invention should be defined based on the meaning of the term and the overall contents of the present invention, not a simple name of the term.

When a part of the specification is said to "include" a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary. In addition, terms such as "... unit" and "module" described in the specification mean units that process at least one function or operation, which may be implemented as hardware or software, or as a combination of hardware and software. . In addition, when a part is said to be "connected" with another part throughout the specification, this includes not only the case of being "directly connected" but also the case of being connected "with another configuration in the middle".

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and similar reference numerals are attached to similar parts throughout the specification.

1 shows a flow chart of the irrigation method using the water stress diagnosis of the crop of the present invention.

Referring to FIG. 1, the present invention may include generating measurement information, calculating an index value of water stress of a crop and an effective soil moisture content, and determining irrigation.

The step of generating the measurement information may be generated by measuring meteorological information including at least one of temperature, humidity, solar radiation, or wind speed of the atmosphere in which the crop is located and the leaf temperature of the crop by a measuring unit.

The present invention can implement an irrigation decision support method for diagnosing crop moisture stress using real-time leaf temperature and weather information of crops, and determining an appropriate irrigation timing and irrigation amount in connection with soil moisture information.

The measurement information may be calculated at a preset specific time period, and may be measured above a preset temperature or below a humidity.

: Crop Water Stress Index)과 토양유효수분함량(

)를 산출할 수 있다.The index value of the moisture stress of the crop in the calculation unit by using the measurement information of a specific time period among the measurement information (

: Crop Water Stress Index) and effective soil moisture content (

) Can be calculated.

)을 비교하고, 토양유효수분함량(

)과 작물의 최대 토양수분허용 부족량(MAD: Maximum Allowable Deficit)의 임계 값과 비교하는 과정을 포함한다.The step of determining irrigation includes an index value and a preset water stress reference value in the control unit through the result of the calculation unit (

) And the effective soil moisture content (

) And the critical value of the Maximum Allowable Deficit (MAD) of the crop.

)은, 상기 작물의 기 설정된 재배기간 동안 상기 지수 값(

)의 평균 값으로 설정될 수 있다.The reference value of the moisture stress (

) Is the index value (

) Can be set as an average value.

Figure 2 shows the appearance of a program implementing the crop moisture stress index (CWSI) calculation method according to an embodiment of the present invention.

Referring to FIG. 2, in order to implement the present invention, a CWSI equation based on an energy balance equation may be used, and moisture stress received by crops according to changes in the atmosphere and soil environment may be quantified.

Crop water stress index (CWSI) value can be used to accurately determine the appropriate irrigation timing of the crop, and the method will be described in detail with the system below in FIG. 3.

An irrigation system to which the above-described irrigation method is applied will be described.

3 shows a state of measuring leaf temperature of a crop according to an embodiment of the present invention.

Referring to FIG. 3, the measurement unit may generate measurement information by measuring meteorological information including at least one of temperature, humidity, solar radiation, or wind speed of the atmosphere in which the crop is located and leaf temperature of the crop.

The measuring unit may include at least one of a thermal imaging camera, an infrared sensor, and a drone to measure leaf temperature.

The left is a thermal imager, the middle is an infrared sensor, and the right is a drone to acquire leaf temperature.

4 shows a state of measuring leaf temperature of a crop through separation between infrared images using a thermal imaging camera according to an embodiment of the present invention.

Referring to FIG. 4, an embodiment of a process of separating a crop and a background space outside the crop and measuring the temperature of the crop through separation between images can be seen.

In the case of leaf temperature entering the crop moisture stress index value calculation, data can be obtained using a total of three methods, such as a thermal imaging camera, an infrared sensor, and a drone, according to an embodiment of the present invention, and the thermal imaging camera is an RGB or infrared image. The leaf temperature can be measured by averaging the temperature and spatial variation of the outer part of the crop by using.

5 to 8 show the relationship between leaf temperature and soil moisture, and the change and correlation of CWSI due to the change in soil moisture content.

5 to 8, it is possible to understand the process of measuring the moisture stress of the present invention, and a detailed embodiment of the present invention will be described later.

5 shows changes in leaf temperature before and after irrigation according to an embodiment of the present invention.

Referring to FIG. 5, it can be seen that leaf temperature of crops clearly appears before and after irrigation, and it can be seen that the correlation between moisture and leaf temperature is considered to determine the irrigation timing and irrigation amount in the present invention.

In the case of crop leaf temperature, there is a distinct difference in temperature increase or decrease (1.5 to 2 degrees Celsius) before and after irrigation, and there may be a correlation between soil moisture change according to irrigation amount and CWSI value.

6 shows a change in CWSI due to a change in soil moisture content according to an embodiment of the present invention.

Referring to FIG. 6, changes in apple CWSI according to soil moisture content (left: July, right September) are shown.

It can be seen that the CWSI value decreases as the amount of irrigation increases and the moisture content in the soil increases. Conversely, the CWSI value increases as the amount of irrigation increases and the moisture content in the soil decreases, and the degree of moisture stress received by the crop increases.

7 and 8 show a correlation between soil moisture content and CWSI according to an embodiment of the present invention, and a comparison between the predicted leaf temperature and the measured leaf temperature using meteorological data.

7 and 8, multiple regression analysis between meteorological information (atmospheric temperature and humidity, solar radiation, wind speed) and leaf temperature is performed to show a high correlation between items.

^{Using this, it is possible to develop a model (R 2} =0.73) that predicts leaf temperature without separately measuring leaf temperature using information on air temperature, humidity, insolation, and wind speed.

According to an embodiment of the present invention, a system and method for implementing an irrigation system may include the following processes. ① By introducing the actual farming method, the irrigation time zone is basically set so that irrigation is not conducted below a certain temperature and above the humidity. ② The total irrigation amount is 80% of the maximum allowable deficit (MAD). It is set and ③ In general, the difference between leaf temperature and atmospheric temperature is maintained at about 3~4 degrees.

In addition, ④ an interface is built to allow irrigation of time and individual zones using an solenoid valve to enable variable irrigation for each zone, and ⑤ reflects the uncertainty of the field environment such as an automatic stop function in case of sudden rainfall, and a delay time setting for rainfall forecasting. You can add modules that can do it.

: Crop Water Stress Index)과 토양유효수분함량(

)를 산출할 수 있다.The calculation unit uses the measurement information of a specific time period among the measurement information to determine the index value of the moisture stress of the crop (

: Crop Water Stress Index) and effective soil moisture content (

) Can be calculated.

: Crop Water Stress Index)은, 엽온과 작물이 위치한 대기 온도 간의 차이의 상한선 및 하한선을 이용하여 아래 수학식 1 내지 수학식 3에 의해 산출될 수 있다.In this process, the index value of the moisture stress of the crop (

: Crop Water Stress Index) may be calculated by Equations 1 to 3 below using an upper limit and a lower limit of the difference between the leaf temperature and the atmospheric temperature at which the crop is located.

: 엽온과 대기온도간의 차이,

: 엽온-대기온도 차의 상한선,

: 엽온-대기온도 차의 하한선)(here,

: Difference between leaf temperature and atmospheric temperature,

: Upper limit of the difference between leaf temperature and atmospheric temperature,

: Lower limit of the difference between leaf temperature and atmospheric temperature)

Here, for reference, the energy equation, soil heat conduction, and sensible heat conduction between soil and atmosphere are expressed as equations as follows.

<Energy Equation>

: 순복사량(W m^-2),

: 토양열전도량(W m^-2),

: 토양과 대기 간 현열 전도량(W m^-2),

: 증발 혹은 응결에 의한 잠열 전도량(W m^-2),

: 호흡 혹은 열저장 등 열전달(W m^-2).

: 대기온도(K),

: 맑은 하늘 방사율,

: 증기압(kPa))(here,

: Net radiation amount (W m ^-2 ),

: Soil heat conductivity (W m ^-2 ),

: Sensitive heat conduction between soil and atmosphere (W m ^-2 ),

: Latent heat conduction by evaporation or condensation (W m ^-2 ),

: Heat transfer such as breathing or heat storage (W m ^-2 ).

: Air temperature (K),

: Clear sky emissivity,

: Vapor pressure (kPa))

<Soil thermal conductivity>

: 열전도율,

: 깊이 z에서의 토양 온도[^oC])(here,

: Thermal conductivity,

: Soil temperature at depth z[ ^o C])

<sensible heat conduction between soil and atmosphere>

: 공기밀도(kg m^-3),

: 공기 열 heat capacity of air(~1013 J kg^{-1 o}C^-1),

: 표면온도(^oC),

: 공기역학적 저항(s m^-1),

: 해수면 위 해발고도(m),

: 풍속측정 높이(m),

: 변위 높이(m),

: 거칠기 길이(m), roughness length (m),

: von Karman 상수 (~0.4),

: 풍속 (m s^-1),

: 외관부 잎 높이(m))(here,

: Air density (kg m ^-3 ),

: Air heat heat capacity of air(~1013 J kg ^{-1 o} C ^-1 ),

: Surface temperature ( ^o C),

: Aerodynamic resistance (sm ^-1 ),

: Altitude above sea level (m),

: Wind speed measurement height (m),

: Displacement height (m),

: Roughness length (m), roughness length (m),

: von Karman constant (~0.4),

: Wind speed (ms ^-1 ),

: Exterior leaf height (m))

<Latent heat conduction by evaporation or condensation>

: 포화대기압(kPa),

: 건습계 상수(kPa ^oC^-1),

: 수분손실에 대한 외관부 엽온 저항값(s m^-1),

: 외관부 엽온와 대기온도의 평균값(^oC))(here,

: Saturated atmospheric pressure (kPa),

: Psychrometer constant (kPa ^o C ^-1 ),

: External leaf temperature resistance value for moisture loss (sm ^-1 ),

: Average value of leaf temperature and air temperature ( ^o C))

In addition, by applying the “FAO 56-Penman Monteith equation”,

(Here, ETo: standard potential evaporation amount (mm/day), ETc: actual evaporation amount (mm/day), Kc: crop coefficient.)

)으로 설정할 수 있다.The crop moisture stress index value is calculated using the leaf temperature and meteorological information of the crop in the test section (e.g., test section II (75% irrigation)) that has obtained the optimal yield and quality, and averaged the value during the cultivation period as follows Final crop moisture stress index reference value (

) Can be set.

)을 비교하고, 토양유효수분함량(

)과 작물의 최대 토양수분허용 부족량(MAD: Maximum Allowable Deficit)의 임계 값과 비교하여 관개를 결정할 수 있다.The control unit, the index value and the preset moisture stress reference value (

) And the effective soil moisture content (

) And the critical value of the Maximum Allowable Deficit (MAD) of the crop to determine irrigation.

: Crop Water Stress Index)이 기 설정된 수분스레스의 기준 값(

)을 초과하고, 토양유효수분함량(

)이 작물의 최대 토양수분허용 부족량(MAD: Maximum Allowable Deficit)의 임계 값 미만인 경우, 아래 표 1과 같이 관개 시작과 종료를 결정할 수 있다. 임계 값은, 80% 미만으로 설정될 수 있다.The control unit, the index value of the moisture stress of the crop (

: Crop Water Stress Index) is the standard value of moisture stress (

), and the effective soil moisture content (

) Is less than the threshold of the Maximum Allowable Deficit (MAD) of the crop, the start and end of irrigation can be determined as shown in Table 1 below. The threshold value may be set to less than 80%.

9 shows the results of analysis of fruit characteristics according to an embodiment of the present invention.

Referring to FIG. 9, it was found that the content of fruit weight, vertical diameter, horizontal diameter, and anthocyanin was higher in the apples harvested in the test plot with high soil moisture content, while the hardness appeared to be highest in the test plot with low soil moisture content. I can.

Therefore, when the present invention is applied, it is possible to establish advanced technology through quantification of crop moisture stress using non-destructive infrared imaging technology and development of appropriate water management technology.

In addition, it is possible to minimize damage while promoting preemptive drought measures such as reducing sun damage, and to provide farmers with production efficiency and increase income by continuing to lay the foundation for cultivation of field crops.

In addition, the establishment of an appropriate irrigation plan and the introduction of automatic control water management technology or system can contribute to water conservation and solving the problem of insufficient labor in agriculture.

In the case of the above system and method, it may be implemented as a computer-readable recording medium in which a program for executing the method is recorded.

Although the present invention has been described in detail through exemplary embodiments above, those of ordinary skill in the art to which the present invention pertains will understand that various modifications can be made to the above-described embodiments without departing from the scope of the present invention. will be. Therefore, the scope of the present invention is limited to the described embodiments and should not be determined, and should be determined by all changes or modifications derived from the claims and the concept of equality as well as the claims to be described later.

Claims (10)

In the irrigation system using the moisture stress diagnosis of crops according to the ratio of the effective moisture content of the soil,
A measuring unit configured to generate measurement information by measuring meteorological information including at least one of temperature, humidity, solar radiation, or wind speed of the atmosphere in which the crop is located and leaf temperature of the crop;
The index value of the moisture stress of the crop by using the measurement information of a specific time period among the measurement information (

: Crop Water Stress Index) and effective soil moisture content (

A calculation unit that calculates ); And
The index value and the preset moisture stress reference value (

), and the effective soil moisture content (

) And a control unit for determining irrigation by comparing with a threshold value of the maximum allowable soil moisture deficit (MAD) of the crop.
The method of claim 1,
The measuring unit,
An irrigation system using at least one of a thermal imaging camera, an infrared sensor, or a drone to measure the leaf temperature.
The method of claim 2,
The thermal imaging camera,
An irrigation system using a moisture stress diagnosis of a crop, characterized in that the leaf temperature is measured by averaging the temperature and spatial variation of the outer part of the crop by using an RGB or infrared image.
The method of claim 1,
The index value of the moisture stress of the crop (

: Crop Water Stress Index),
An irrigation system using a moisture stress diagnosis of a crop, characterized in that calculated using an upper limit and a lower limit of the difference between the leaf temperature and the atmospheric temperature in which the crop is located.
The method of claim 1,
The control unit,
The index value of the moisture stress of the crop (

: Crop Water Stress Index) is the standard value of moisture stress (

) Exceeds,
The effective soil moisture content (

) Is less than the threshold of the maximum allowable soil moisture deficit (MAD) of the crop, irrigation system using the water stress diagnosis of a crop, characterized in that to determine the start of irrigation.
The method of claim 5,
The threshold is,
Irrigation system using the water stress diagnosis of crops, characterized in that less than 80%.
In the irrigation method using the moisture stress diagnosis of crops according to the ratio of the effective moisture content of the soil,
Generating measurement information by measuring meteorological information including at least one of temperature, humidity, insolation, or wind speed of the atmosphere in which the crop is located and leaf temperature of the crop by a measuring unit;
The index value of the moisture stress of the crop in the calculation unit by using the measurement information of a specific time period among the measurement information (

: Crop Water Stress Index) and effective soil moisture content (

Calculating ); And
Based on the result of the calculation unit, the control unit determines the index value and the reference value of the preset moisture stress (

), and the effective soil moisture content (

) And the irrigation method using the water stress diagnosis of a crop comprising the step of determining irrigation by comparing with a threshold value of the maximum allowable soil moisture deficit (MAD) of the crop.
The method of claim 7,
The measurement information is,
It can be calculated at a specific time period set in advance,
An irrigation method using the diagnosis of moisture stress of a crop, characterized in that it is measured above a preset temperature or below a humidity.
The method of claim 7,
The reference value of the moisture stress (

)silver,
The index value (

) Irrigation method using the water stress diagnosis of crops, characterized in that set to the average value.
A computer-readable recording medium storing a program for executing the method of any one of claims 7 to 9.

Images