A real-time weight-based facility substrate blueberry environmental decision-making irrigation method

Abstract

The application relates to a real-time weight-based facility substrate blueberry environment decision-making irrigation method, which comprises the following steps S1: establishing a linear relationship between the substrate weight of blueberries and the substrate humidity; S2: correcting the linear relationship obtained in step S1 by using the total weight of real-time blueberry plants and substrates to obtain a corrected linear relationship; S3: assembling a weight monitoring unit, collecting the total weight of real-time blueberry plants and substrates, and constructing a total weight dataset; S4: assembling an environment factor collecting unit, constructing an environment factor dataset; assembling an irrigation discharge liquid monitoring unit, and constructing a discharge liquid volume dataset; S5: according to the environment factor dataset, the total weight dataset and the discharge liquid volume dataset, establishing an environment decision-making irrigation model with four parameters of an irrigation start time, an irrigation end time, an irrigation frequency and a single irrigation amount; and S6: assembling an irrigation execution unit, realizing quantitative irrigation according to the irrigation decision made by the environment decision-making irrigation model.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of facility crop planting, and particularly relates to a facility substrate blueberry environment decision irrigation method based on real-time weight. BACKGROUND

[0002] Blueberries are fruits rich in various nutrients, and people's daily demand for blueberries increases year by year. Blueberries have been introduced and cultivated in China. Blueberries are shallow-rooted plants with underdeveloped root systems and poor absorption capacity. Planting blueberries has very high requirements for the growing environment, and the suitability of soil conditions directly affects the yield and quality of blueberries. The soil in China is mostly acidic, with low fertility and low organic matter content, which limits the growth of blueberries. Therefore, facility cultivation of blueberries has become an important means of planting blueberries in China.

[0003] At present, the irrigation of facility substrate blueberries mainly relies on environmental conditions, through temperature, light, humidity and other environmental sensors, combined with pH, EC, substrate humidity and other root zone environmental sensors to collect environmental data, but these data cannot directly reflect the overall photosynthesis and transpiration of blueberry plants. In the existing irrigation model, substrate humidity is often used as a reference, but the water distribution in the substrate is uneven, and the sensor can only collect local substrate information, resulting in inaccurate humidity data and seriously affecting the irrigation accuracy. In addition, sunlight facility substrate cultivation of blueberries mainly relies on manual experience management, which has the problems of low standardization of management, difficulty in precise control of the growing environment and high labor cost, which seriously affects the further development of the blueberry industry. SUMMARY

[0004] In view of the above problems, the application provides a facility substrate blueberry environment decision irrigation method based on real-time weight, which comprises the following steps:

[0005] S1: establishing a linear relationship between the substrate weight and the substrate humidity of blueberries;

[0006] S2: correcting the linear relationship obtained in step S1 using the total weight of the real-time blueberry plant and the substrate to obtain a corrected linear relationship;

[0007] S3: assembling a weight monitoring unit to collect the total weight of the real-time blueberry plant and the substrate and construct a total weight data set;

[0008] S4: assembling an environmental factor acquisition unit to construct an environmental factor data set; assembling an irrigation effluent monitoring unit to construct an effluent volume data set;

[0009] S5: establishing an environment decision irrigation model according to the environmental factor data set, the total weight data set and the effluent volume data set, with four parameters of irrigation start time, irrigation end time, irrigation frequency and single irrigation amount;

[0010] S6: Assemble an irrigation execution unit to implement quantitative irrigation according to the irrigation decision made by the environment decision irrigation model.

[0011] In the traditional irrigation technology, real-time humidity is taken as the basis for irrigation. In order to solve the problem of uneven distribution of humidity in the substrate, the substrate weight is used instead of humidity in the present application to establish a linear relationship between the substrate weight and the substrate humidity of blueberries, so as to associate the substrate weight with the humidity, so that the overall irrigation decision can also include the humidity factor. Further, in the actual planting process, it is impossible to weigh the substrate weight alone, and more importantly, the weight of the blueberry plant is the most intuitive factor reflecting the growth of blueberries, which should be an important consideration factor for irrigation. Therefore, the present application takes the total weight of the real-time blueberry plant and the substrate as the actual collection object, and corrects the linear relationship obtained in step S1 with the total mass to obtain the relationship between the total mass and the substrate humidity. Then, the present application further assists with the environmental factor data set and the discharge liquid volume data set to establish an environment decision irrigation model to obtain the irrigation start time, the irrigation end time, the irrigation frequency and the single irrigation amount, thereby specifically guiding the actual irrigation operation. The present application takes the growth state of the blueberry plant and the state of the facility environment as the model basis, and the irrigation model constructed is highly targeted, which achieves scientific irrigation, water saving and labor saving, and also guarantees the yield and quality of blueberries.

[0012] Optionally, step S1 is specifically:

[0013] (1) drying the substrate to be planted after pretreatment to a constant weight to obtain dry substrate, and then dividing the dry substrate into several equal parts of equal mass;

[0014] (2) adding irrigation liquid fertilizer of different weights to each part of the dry substrate, and weighing after standing to obtain the total weight SubWei of each part of the dry substrate after adding the irrigation liquid fertilizer;

[0015] (3) linearly fitting the total weight of each part of the dry substrate after adding the irrigation liquid fertilizer with the substrate humidity Hum to obtain the linear relationship between the substrate weight and the substrate humidity Hum=k×SubWei-a,

[0016] wherein Hum is the percentage of the weight of water in the substrate to the dry weight of the substrate, and k and a are constant parameters. If k>0, the substrate weight is proportional to the substrate humidity.

[0017] Further, the substrate is coconut fiber, the pretreatment is to rinse the substrate with clean water, then drain the water, measure the conductivity of the drained water, and compare it with the preset conductivity value. If the conductivity of the drained water is higher than the preset conductivity, repeat the rinsing and draining until the conductivity of the drained water is slightly lower than the preset conductivity. Unrinsed coconut fiber has a high salt content, which can cause blueberry root rot. Rinsing the substrate with water can wash away the salt, and the conductivity can be used as a measure to reduce the salt content in the substrate to an appropriate level.

[0018] Further, in step (1), the constant weight requires that the difference between two consecutive weighings is less than 3 mg to ensure that the substrate has reached a completely dried state.

[0019] Further, in step (1), 11 samples are prepared, and in step (2), the irrigation fertilizer solution weights of the 11 samples are 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100% of the dry weight of the substrate, respectively, to ensure a linear relationship and a Hum coverage range of 0-100%.

[0020] When the irrigation fertilizer solution weight approaches the dry weight of the substrate, i.e., Hum approaches 100%, continue to increase the irrigation fertilizer solution weight. The fertilizer solution may be saturated, and after the irrigation fertilizer solution reaches the preset weight, the Hum and SubWei values at this time are obtained, then wait for the fertilizer solution to fully mix with the substrate, and then wait for the fertilizer solution to be completely drained.

[0021] The weight of the blueberry plant directly reflects the overall growth level of the blueberry, and can be used as an important phenotypic indicator to evaluate the growth status of the blueberry plant. The total weight of the blueberry plant and the substrate within a day changes mainly due to irrigation water absorption and transpiration, so the total weight of the blueberry plant and the substrate can be used as an indirect indicator to comprehensively and accurately represent the change in substrate humidity.

[0022] Optionally, in step S2, the total weight of the blueberry plant and the substrate is measured in real time after the facility blueberry is planted. As the growth cycle progresses, the weight of the blueberry plant will gradually increase, and the linear relationship in step S1 needs to be corrected.

[0023] The weight parameter in the corrected linear relationship includes the growth amount of the plant and the weight of the substrate. The interval from the end of irrigation on the previous day to the start of irrigation on the second day is generally more than 12 hours, and it is assumed that the substrate humidity at 6 am on each test day remains the same. Therefore, the increase in the total weight of the blueberry plant and the substrate measured at 6 am on different test days is the growth amount of the plant.

[0024] The corrected linear relationship is Hum j-i = k × (SBBWei j-i - BBWei0- ΔBBWei j )- a,

[0025] Wherein, j is the test days, i is any time point on the test day; ΔBBWei j is the difference between the total weight of blueberry plants and substrate at 6 am on the jth day of the test and the total weight of blueberry plants and substrate at 6 am on the first day of the test, that is, the growth amount of the plants after j days of the test; BBWei0 is the weight of the blueberry plants before planting; SBBWei j-i is the total weight of real-time blueberry plants and substrate at any time on the jth day of the test; Hum j-i is the substrate humidity at any time on the jth day of the test.

[0026] Further, the modified linear relationship is deformed as follows:

[0027] SBBWei j-i = (Hum j-i +a) / k+BBWei0+ΔBBWei j ,

[0028] The above formula can be deformed as follows: j-best SBBWei best = (Hum j +a) / k+BBWei0+ΔBBWei j-best ,

[0029] Wherein, SBBWei best is the target total weight of blueberry plants and substrate on the jth day of the test; Hum j-best is the substrate humidity most suitable for the growth of blueberries.

[0030] The present application establishes the above relationship, that is, establishes the relationship between SBBWei best and Hum j and ΔBBWei j , ΔBBWei j-best increases as the plant growth cycle lengthens, so SBBWei best varies with the plant growth cycle. Hum

[0031] In the modified linear relationship, the total weight of blueberry plants and substrate is used instead of the weight of the substrate after irrigation with fertilizer solution. In step S3, the total weight of blueberry plants and substrate is collected and uploaded in real time by the weight monitoring unit, the collection time range is from the planting day to the completion of fruit picking, the collection frequency is to upload data to the server database every 10 minutes, to build a total weight data set, and to ensure data accumulation during the entire growth cycle of the facility substrate blueberry.

[0032] Optionally, the weight monitoring unit comprises a support, a planting pot and a weighing device, the support is supported on the ground, the weighing device is arranged on the top of the support, the planting pot is filled with substrate and blueberry plants, the planting pot is connected to the weighing device by a rope, and the planting pot is hung in the air, so that excess fertilizer solution can be easily discharged.

[0033] The weighing device is communicatively connected to the data processing device and the server, and the collected weight data is transmitted to the data processing device in real time and stored in the server.

[0034] Optionally, in step S4, the environmental factor acquisition unit comprises a temperature sensor, an illumination intensity sensor and a photosynthetically active radiation sensor, and the three sensors are installed at a distance of 15-20 cm from the top of the blueberry plants.

[0035] Optionally, the constructed environmental factor data set comprises data sets of three parameters of facility temperature, illumination intensity and photosynthetically active radiation, and the time and frequency of data acquisition are the same as those of the weight data acquisition in step S3, thereby providing a data basis for the establishment of the irrigation model.

[0036] The temperature influences the evaporation and transpiration of the plants, and the evaporation and transpiration are directly related to the irrigation amount. The illumination intensity is related to the photosynthesis of the plants, and the photosynthesis synthesizes sugar that supports the growth of the plants and is directly related to the real-time weight of the plants. The photosynthetically active radiation represents the conversion efficiency of solar energy and is related to the photosynthesis efficiency.

[0037] Optionally, the irrigation discharge liquid monitoring unit comprises a discharge pipe and a liquid volume sensor, and the bottom of the planting pot is connected to the liquid volume sensor through the discharge pipe; the liquid volume sensor is a tipping-bucket rain sensor.

[0038] Optionally, the constructed discharge liquid volume data set refers to the irrigation liquid volume flowing out of the substrate after irrigation, and the data is measured by the liquid volume sensor, the acquisition time is within 1 hour after each irrigation, and the acquisition frequency is to upload data to the server database every 1 minute, while the data is set to be cleared at 0 o'clock every day, so that the cumulative amount of the discharge liquid of each test day is new data, and the test results of the previous day do not affect the test data of the current day.

[0039] Preferably, the discharge liquid volume and the time of the first appearance of the discharge liquid within one day are important indicators for adjusting the irrigation model. When the irrigation discharge liquid appears, it indicates that the water content in the substrate is sufficient at this time, and the discharge of the irrigation discharge liquid carries away the waste in the substrate, thereby improving the air permeability of the substrate. Therefore, a certain volume of irrigation discharge liquid needs to be ensured every test day.

[0040] The discharge liquid volume obtained after each irrigation should be basically consistent, which not only ensures the growth of the plants, but also is beneficial to water and fertilizer saving.

[0041] Optionally, in step S5, the establishment of the environment decision irrigation model is based on the total weight data set, the environment factor data set, and the irrigation liquid volume data set, and relies on four key parameters of irrigation start time, irrigation end time, irrigation frequency, and single irrigation amount to construct an irrigation model.

[0042] The irrigation start time is related to two environment factors of facility internal temperature and illumination intensity. When the illumination intensity first reaches 15000 LUX and the temperature first reaches 15℃, the time point is the irrigation start time.

[0043] The irrigation end time is related to the photosynthetically active radiation value. When the photosynthetically active radiation is 0, the irrigation is stopped.

[0044] After the long water draining process at night, the water in the substrate reaches a stable state at 6 am. After sunrise, the facility internal temperature gradually increases, the illumination intensity gradually increases, the evaporation of the plant gradually increases, the water absorption of the plant root gradually increases, and the total weight of the blueberry plant and the substrate continuously decreases. When the illumination intensity first reaches 15000 LUX and the temperature first reaches 15℃, the water absorption and transpiration of the whole plant are active, and the total weight of the blueberry plant and the substrate reaches the lowest, and the irrigation can be started.

[0045] The photosynthetically active radiation indirectly represents the photosynthesis efficiency. When the photosynthetically active radiation is 0, the solar energy conversion efficiency is low, and the whole plant activity is low. At this time, the irrigation is stopped, the water in the substrate is preserved to offset the transpiration before sunset, and the root disease caused by high water content in the substrate at night is avoided.

[0046] Further optionally, the single irrigation amount is based on the total weight of the blueberry plant and the substrate, the total weight of the target blueberry plant and the substrate is SBBWei j-best , and the time point when the irrigation discharge liquid appears is the demarcation point.

[0047] Before the demarcation point, the single irrigation amount should be (SBBWei j-best -SBBWei j0 ) / n, SBBWei j0 is the total weight of the blueberry plant and the substrate corresponding to the irrigation start time on the jth day of the test; according to the principle of a small amount of multiple times, n is the empirical value of the minimum irrigation frequency before reaching the target total weight of the blueberry plant and the substrate, and n is 4-6.

[0048] After the demarcation point, the single irrigation amount is SBBWei j-best -SBBWei j-0 , and SBBWei j-0 is the total weight of the blueberry plant and the substrate before the start of this irrigation.

[0049] Before the demarcation point, the water content in the substrate is greatly different from the target total weight of the blueberry plant and the substrate; after the demarcation point, the water content in the substrate is sufficient, and the above difference is smaller, and the single irrigation amount only needs to make up the difference to maintain the total weight of the blueberry plant and the substrate around the target total weight of the blueberry plant and the substrate, and accordingly the single irrigation amount should be adjusted. The different single irrigation amounts before and after the demarcation point ensure that the total weight of the blueberry plant and the substrate before the demarcation point presents an overall rising trend and gradually approaches the target weight value, and presents a stable trend around the target weight value after the demarcation point.

[0050] Further optionally, the irrigation frequency is based on the change of the total weight of the blueberry plant and the substrate, and after once irrigation, the total weight of the blueberry plant and the substrate gradually increases, and with the increase of transpiration and photosynthesis, the total weight gradually decreases after reaching the highest point, and when the difference between the real-time total weight and the highest point reaches 50% of the last irrigation amount, the next irrigation is started, so as to determine the irrigation frequency.

[0051] The present application links and restricts the single irrigation amount and the irrigation frequency, and they present an inverse relationship, that is, the single irrigation amount is more, and the irrigation frequency is relatively reduced, and the single irrigation amount is less, and the irrigation frequency is relatively increased.

[0052] Optionally, in the step S6, the irrigation execution unit comprises a fertilizer liquid barrel and an irrigation pipe, the fertilizer liquid barrel is connected with the planting pot through the irrigation pipe, but the irrigation pipe does not exert force on the planting pot, the outlet end of the irrigation pipe is provided with an electromagnetic valve, the electromagnetic valve is communicatively connected with the data processing device, and the specific irrigation decision is made according to the environmental decision irrigation model of the step S5, that is, the timing opening and closing of the electromagnetic valve is completed, and in the case that the irrigation flow rate is fixed, the irrigation time length is used to control the irrigation amount.

[0053] The present application aims at the low precision in the existing irrigation process, such as insufficient irrigation and excessive irrigation, and uses the real-time weight of the blueberry plant and the growth environment information to establish a model for precise, scientific and efficient irrigation control, which not only improves the water and fertilizer utilization rate, but also helps to improve the yield and quality of blueberry fruits and save labor cost. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 The flow chart of the irrigation method of the embodiment;

[0055] Figure 2 The structural schematic view of the weight monitoring unit, the environmental factor collecting unit and the irrigation effluent monitoring unit;

[0056] Figure 3 The relationship diagram of the irrigation method.

[0057] In the drawings, 1 is a support, 2 is a planting pot, 3 is a weighing device, 4 is a data processing device, 5 is a server, 6 is a temperature sensor, 7 is an illumination intensity sensor, 8 is a photosynthetically active radiation sensor, 9 is a discharge pipe, 10 is a liquid volume sensor, 11 is a fertilizer liquid barrel, 12 is an irrigation pipe, and 13 is an electromagnetic valve. DETAILED DESCRIPTION

[0058] The embodiment provides a facility substrate blueberry environment decision-making irrigation method based on real-time weight, as shown in Figure 1 and Figure 3 , comprising the following steps:

[0059] S1: establishing a linear relationship between the substrate weight of blueberries and the substrate humidity;

[0060] S2: correcting the linear relationship obtained in step S1 by using the total weight of the real-time blueberry plant and the substrate to obtain a corrected linear relationship;

[0061] S3: assembling a weight monitoring unit, collecting the total weight of the real-time blueberry plant and the substrate, and constructing a total weight data set;

[0062] S4: assembling an environment factor collection unit to construct an environment factor data set; assembling an irrigation discharge liquid monitoring unit to construct a discharge liquid volume data set;

[0063] S5: establishing an environment decision-making irrigation model according to the environment factor data set, the total weight data set, and the discharge liquid volume data set, with four parameters of irrigation start time, irrigation end time, irrigation frequency, and single irrigation amount;

[0064] S6: assembling an irrigation execution unit to realize quantitative irrigation according to the irrigation decision made by the environment decision-making irrigation model.

[0065] Step S1 is specifically:

[0066] (1) drying the substrate (coconut husk) to be planted after pre-treatment and washing in 105℃ for 12 hours to constant weight to obtain dry substrate, and then dividing the dry substrate into 11 equal parts with equal mass;

[0067] (2) adding irrigation liquid with different weights to each part of the dry substrate, and weighing after standing for 30 minutes to obtain the total weight SubWei of each part of the dry substrate after adding the irrigation liquid;

[0068] The irrigation liquid weights of the 11 samples are 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100% of the dry weight of the substrate, respectively;

[0069] (3) Linear fitting of the total weight of each dry substrate added to the irrigation fertilizer solution and the substrate humidity Hum, obtaining the linear relationship between the substrate weight and the substrate humidity Hum=k×SubWei-a=15×SubWei-121.25,

[0070] wherein Hum is the weight percentage of water in the substrate to the dry weight of the substrate.

[0071] In step S2, after the facility blueberry is planted, the total weight of the blueberry plant and the substrate is measured in real time, and the corrected linear relationship is Hum j-i =15×(SBBWei j-i -BBWei0-ΔBBWei j )-121.25,

[0072] wherein j is the test day, i is any time point on the test day; ΔBBWei j is the difference between the total weight of the blueberry plant and the substrate at 6 am on the jth test day and the total weight of the blueberry plant and the substrate at 6 am on the first test day, i.e., the growth amount of the plant after j days of test; BBWei0 is the weight of the blueberry plant before planting, specifically 6.72 kg; SBBWei j-i is the total weight of the blueberry plant and the substrate at any time on the jth test day; Hum j-i is the substrate humidity at any time on the jth test day.

[0073] The corrected linear relationship is transformed into SBBWei j-i =(Hum j-i +121.25) / 15+BBWei0+ΔBBWei j , which can be transformed into SBBWei j-best =(Hum best +121.25) / 15+BBWei0+ΔBBWei j ,

[0074] SBBWei j-best =(Hum best +121.25) / 15+6.72+ΔBBWei j ;

[0075] wherein SBBWei j-best is the target total weight of the blueberry plant and the substrate on the jth test day; Hum best is the substrate humidity most suitable for the growth of blueberries; during the flower bud differentiation period of blueberry growth, Hum best is about 25%; during the flowering period of blueberry growth, Hum best is about 43%; and during the fruiting period of blueberry growth, Hum best is about 39%.

[0076] In step S3, the total weight of the blueberry plant and the substrate is collected by the weight monitoring unit in real time, the collection time range is from the planting day to the completion of fruit picking, the collection frequency is to upload data to the server database every 10 minutes, and the total weight dataset is constructed.

[0077] The weight monitoring unit comprises a support 1, a planting pot 2 and a weighing device 3. The support is supported on the ground, the weighing device is arranged at the top of the support, the planting pot contains the substrate and the blueberry plant, and the planting pot is connected to the weighing device by a rope to hang in the air, facilitating the discharge of excess fertilizer liquid.

[0078] The weighing device is communicatively connected to a data processing device 4 and a server 5, and the collected weight data is transmitted to the data processing device in real time and stored in the server. Before the test, the empty planting pot is weighed first, so that the weight of the empty planting pot is subtracted during subsequent weighing.

[0079] The data processing device completes the data integration of the real-time weight dataset, the environmental factor dataset and the discharged liquid volume dataset through the module RSM485M, uses the chip STM32F103RCT6 as the core to complete data analysis and model establishment, uses the optical coupling device PC817 to realize 3.3V to 24V conversion control, and operates the irrigation execution unit.

[0080] In step S4, the environmental factor collection unit comprises a temperature sensor 6, an illumination intensity sensor 7 and a photosynthetically active radiation sensor 8. The three sensors are installed 15-20 cm away from the top of the blueberry plant, can accurately reflect the environmental parameters from the bottom to the top of the plant, and can avoid the shading of surrounding high plants without affecting the growth of the test plants.

[0081] The construction of the environmental factor dataset comprises the construction of the datasets of the three parameters of the facility temperature, the illumination intensity and the photosynthetically active radiation, and the collection time and frequency are the same as those of the weight data collection in step S3, which provides a data basis for the formulation of the irrigation model.

[0082] The irrigation discharge liquid monitoring unit comprises a discharge pipe 9 and a liquid volume sensor 10. The bottom of the planting pot is connected to the liquid volume sensor through the discharge pipe, and the discharge pipe does not exert force on the liquid volume sensor, so the weight of the discharge pipe can be included in the weight of the planting pot.

[0083] The liquid volume sensor is a tipping bucket rain sensor to measure irrigation liquid in the form of drops. The tipping bucket rain sensor has a diameter D = 200 mm, so the radius R = D / 2. The measured liquid volume unit is converted from mm to mL by (π*R*R*H) / 1000, where H (height) is the data measured by the rain sensor.

[0084] The construction of the discharge liquid volume data set refers to the collection of irrigation liquid volume flowing out of the substrate after irrigation, and the data is obtained by measuring the liquid volume sensor. The collection time is within 1 hour after the start of each irrigation, and the collection frequency is uploading data to the server database every 1 minute, while setting the data to zero at 0 o'clock every day.

[0085] In step S5, the establishment of the environmental decision irrigation model is based on the total weight data set, the environmental factor data set, and the discharge liquid volume data set, and relies on four key parameters: irrigation start time, irrigation end time, irrigation frequency, and single irrigation amount to construct an irrigation model.

[0086] The irrigation start time is related to two environmental factors: facility temperature and light intensity. When the light intensity first reaches 15000LUX and the temperature first reaches 15℃, the time point is the irrigation start time.

[0087] The irrigation end time is related to the photosynthetically active radiation value. When the photosynthetically active radiation is 0, irrigation is stopped.

[0088] The single irrigation amount is based on the total weight of blueberry plants and substrate, and the target SBBWei j-best is the total weight of blueberry plants and substrate, based on Hum best and ΔBBWei j , SBBWei j-best is 17.4 kg on a certain day during flower bud differentiation, 19.14 kg on a certain day during flowering, and 19.4 kg on a certain day during fruiting, with the time point of irrigation discharge liquid as the dividing point.

[0089] Taking the flower bud differentiation period as an example, SBBWei j-best is 17.4 kg, and before the dividing point, the single irrigation amount should be (SBBWei j-best -SBBWei j0 ) / n, SBBWei j0 is the total weight of blueberry plants and substrate corresponding to the irrigation start time on the jth day of the test, and SBBWei j0 is specifically 16.4 kg, n = 4, and the single irrigation amount is 0.25 kg at this time.

[0090] After the dividing point, the single irrigation amount is SBBWei j-best -SBBWeij-0 , about 0.1 kg, SBBWei j-0 is the total weight of the blueberry plant and the substrate before the start of this irrigation, SBBWei j-0 around 17.3 kg up and down.

[0091] The irrigation frequency is based on the change in the total weight of the blueberry plant and the substrate. When the difference between the real-time total weight and its highest point reaches 50% of the last irrigation amount, the next irrigation is started. In this way, the irrigation frequency is determined.

[0092] In step S6, the irrigation execution unit includes a fertilizer liquid barrel 11 and an irrigation pipe 12. The fertilizer liquid barrel is connected to the planting pot through the irrigation pipe, but the irrigation pipe does not exert force on the planting pot. The outlet end of the irrigation pipe is provided with a solenoid valve 13, which is communicatively connected to the data processing device. According to the environmental decision-making irrigation model of step S5, the specific irrigation decision is made, i.e. the timing of opening and closing of the solenoid valve is completed. In the case of fixed irrigation flow rate, the irrigation amount is controlled by using the irrigation time length.

[0093] In summary, in the irrigation method, the real-time total weight of the blueberry plant and the substrate changes in stages. The first stage is from 6 am to sunrise, and the total weight is stable and basically unchanged. The second stage is from sunrise to the start of irrigation. Due to the gradual increase of photosynthesis and transpiration after sunrise, the water content in the substrate decreases, and the total weight gradually decreases, reaching the lowest point of the day at the start of irrigation. The third stage is from the start of irrigation to the dividing point. After the end of the first irrigation, the total weight gradually increases. At this time, the irrigation liquid and the substrate are fully mixed. Then, due to photosynthesis and transpiration, the total weight gradually decreases to the next irrigation. Because the single irrigation amount before the dividing point is equal, with the increase of temperature and light, the total weight decreases faster and faster, and the irrigation interval becomes shorter and shorter. The total weight shows an overall upward trend and gradually approaches the target total weight value. In the fourth stage, from the dividing point to the end of irrigation, the total weight tends to be stable and fluctuates around the target total weight value through real-time adjustment of the irrigation model. In the fifth stage, from the end of irrigation to sunset, the total weight continuously decreases due to transpiration. In the sixth stage, from sunset to 6 am the next day, the total weight decreases at a slower rate and gradually stabilizes. The plant enters the resting stage.

Claims

1. A facility substrate blueberry environmental decision irrigation method based on real-time weight, characterized in that, Includes the following steps: S1: Establish a linear relationship between the substrate weight and substrate moisture content of blueberries; S2: Correct the linear relationship obtained in step S1 using the total weight of the blueberry plants and substrate in real time to obtain the corrected linear relationship; S3: Set up a weight monitoring unit to collect the total weight of blueberry plants and substrate in real time and build a total weight dataset; S4: Establish an environmental factor acquisition unit and construct an environmental factor dataset; establish an irrigation discharge monitoring unit and construct a discharge volume dataset; S5: Based on the environmental factor dataset, total weight dataset, and discharged liquid volume dataset, establish an environmental decision irrigation model with four parameters: irrigation start time, irrigation end time, irrigation frequency, and single irrigation volume. S6: Establish an irrigation execution unit to implement quantitative irrigation based on the irrigation decisions made by the environmental decision irrigation model; In step S2, after the blueberry plants are planted in the facility, the corrected linear relationship is Hum. j-i =k×(SBBWei j-i -BBWei0-ΔBBWei j )-a, Where k and a are constant parameters, j is the number of experimental days, and i is any time point on the day of the experiment; ΔBBWei j The difference between the total weight of the blueberry plants and substrate at 6:00 AM on day j of the experiment and at 6:00 AM on day one of the experiment represents the plant growth after day j. BBWei0 represents the weight of the blueberry plants before planting; SBBWei j-i The total weight of blueberry plants and substrate at any time on day j of the experiment; Hum j-i The substrate humidity at any time on day j of the experiment; The modified linear relationship is transformed into: SBBWei j-best =(Hum best +a) / k+BBWei0+ΔBBWei j , Among them, SBBWei j-best The total weight of the target blueberry plants and substrate on day j of the experiment; Hum best The optimal substrate moisture for blueberry growth; The single irrigation amount is based on the total weight of the blueberry plants and substrate, using SBBWei j-best The total weight of the target blueberry plants and substrate is used as the dividing point, with the time point when the irrigation drainage liquid appears as the dividing point. Before the dividing point, the single irrigation volume should be (SBBWei) j-best -SBBWei j0 ) / n,SBBWei j0 The total weight of blueberry plants and substrate corresponding to the start time of irrigation on day j of the experiment; n is the number of irrigations, n is 4-6; After the dividing point, the single irrigation volume is SBBWei j-best -SBBWei j-0 SBBWei j-0 This represents the total weight of the blueberry plants and substrate before the start of this irrigation.

2. The facility substrate blueberry environmental decision irrigation method based on real-time weight according to claim 1, characterized in that, Step S1 is as follows: (1) After pretreatment, the substrate that is about to be planted is dried to constant weight to obtain dry substrate, and then the dry substrate is divided into several equal parts of equal weight. (2) Add different weights of irrigation fertilizer solution to each part of dry substrate, let it stand, and weigh it to obtain the total weight of each part of dry substrate after adding irrigation fertilizer solution, SubWei. (3) The total weight of each dry substrate after adding irrigation fertilizer solution was linearly fitted with the substrate moisture Hum to obtain the linear relationship between substrate weight and substrate moisture: Hum = k × SubWei - a. Here, Hum is the percentage of the weight of water in the matrix relative to the dry weight of the matrix.

3. The facility substrate blueberry environmental decision irrigation method based on real-time weight according to claim 2, characterized in that, The substrate is coconut coir. The pretreatment involves rinsing the substrate with clean water and draining it, measuring the conductivity of the drained water, and comparing it with a preset conductivity value. If the conductivity of the drained water is higher than the preset conductivity, the substrate is rinsed and drained again until the conductivity of the drained water is slightly lower than the preset conductivity.

4. The facility substrate blueberry environmental decision irrigation method based on real-time weight according to claim 2, characterized in that, In step (1), 11 samples are prepared. In step (2), the irrigation fertilizer liquid weights of the 11 samples are 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100% of the dry weight of the substrate, respectively.

5. The facility substrate blueberry environmental decision irrigation method based on real-time weight according to claim 1, characterized in that, In step S3, the weight monitoring unit includes a support, a planting pot, and a weighing device. The bottom of the support is supported on the ground, and the weighing device is set on the top of the support. The planting pot contains substrate and blueberry plants. The planting pot is connected to the weighing device by a rope, suspending the planting pot in mid-air to facilitate the drainage of excess fertilizer solution. The weighing device communicates with the data processing equipment and the server, transmitting the collected weight data to the data processing equipment in real time and then storing it on the server. The total weight of the blueberry plants and substrate is collected and uploaded in real time by the weight monitoring unit. The collection time range is from the day of planting to the completion of all fruit harvesting. The data is uploaded to the server database every 10 minutes to construct the total weight dataset.

6. The facility substrate blueberry environmental decision irrigation method based on real-time weight according to claim 1, characterized in that, In step S4, the environmental factor acquisition unit includes a temperature sensor, a light intensity sensor, and a photosynthetically active radiation sensor. These three sensors are installed 15-20 cm away from the top of the blueberry plant. The construction of the environmental factor dataset includes the construction of a dataset of three parameters: facility temperature, light intensity, and photosynthetically active radiation. The irrigation discharge monitoring unit includes a discharge pipe and a liquid volume sensor. The bottom of the planting pot is connected to the liquid volume sensor through the discharge pipe, and the discharge pipe does not apply any force to the liquid volume sensor. The liquid volume sensor is a tipping bucket rain gauge.

7. The facility substrate blueberry environmental decision irrigation method based on real-time weight according to claim 6, characterized in that, In step S5, the irrigation start time is related to two environmental factors: temperature and light intensity within the facility. The irrigation start time is the point at which the light intensity first reaches 15,000 LUX and the temperature first reaches 15°C. The irrigation end time is related to the photosynthetically active radiation value; irrigation is stopped when the photosynthetically active radiation is 0.

Images