Plant water, fertilizer, gas and heat dynamic regulation system and method based on osmotic potential closed loop adaptation

Abstract

The application relates to the technical field of plant cultivation irrigation and water and fertilizer regulation, and discloses a plant water and fertilizer gas and heat dynamic regulation system based on osmotic potential closed loop self-adaption. The system comprises a water potential regulation container, a semi-permeable membrane osmotic induction assembly, a water potential difference driven bidirectional locking switch unit and a water and fertilizer supply unit which are sequentially sealed and communicated and jointly construct an osmotic potential induction inner closed loop and a water and fertilizer supply outer closed loop; the water potential regulation container is a cylindrical sealed pressure-bearing container. The system adopts a double closed loop collaborative regulation architecture, realizes double dimension water potential accurate regulation, and completes system on-off control through the water potential difference driven bidirectional locking switch, can solve the technical problems that in the prior art, temperature change leads to osmotic potential drift and the switch is not tightly turned off, the water potential regulation precision can reach + / -0.002 MPa, the water and fertilizer utilization rate is effectively improved, the system is stable and reliable in operation, and can be modularized and scaled and applied to large-scale cultivation scenes of various terrestrial plants.

Description

Technical Field

[0001] This invention relates to the field of plant cultivation irrigation and water and fertilizer regulation technology, specifically to a plant water, fertilizer, air and heat dynamic regulation system and method based on osmotic potential closed-loop adaptive regulation. Background Technology

[0002] Current plant irrigation technologies are mainly divided into three categories: traditional irrigation, automated irrigation, and negative pressure / micro-irrigation. All of them have insurmountable technical limitations.

[0003] Traditional irrigation methods (manual flood irrigation, sprinkler irrigation, drip irrigation, etc.) rely on human experience and judgment, resulting in low water and fertilizer utilization rates. They cannot accurately match the real-time needs of plants and are prone to waterlogging, drought, or resource waste. Home gardening DIY drip irrigation devices can only achieve a fixed flow rate and slow dripping, which cannot adapt to the different needs of different plant varieties and growth stages.

[0004] There is currently no reliable dual-closed-loop control architecture, which cannot achieve decoupling and coordination between root zone osmotic potential sensing and water and fertilizer supply. The control accuracy is only ±0.02MPa. It can only adjust water potential in one dimension and cannot solve the industry pain point of osmotic potential drift caused by environmental temperature fluctuations. The temperature compensation accuracy of existing technologies is only ±10%-±20%, and the long-term operation stability is poor.

[0005] Existing control devices either rely on power electronic components, making them unusable in scenarios without electricity; or they lack a reliable bidirectional locking and shut-off structure, with a reverse pressure resistance of less than 0.05MPa, making them prone to leakage and backflow, unable to eliminate flooding and drought problems at their source. At the same time, they cannot achieve independent and precise control in large-scale zones, making it difficult to adapt to the differentiated cultivation needs of various crops.

[0006] To address the shortcomings of the prior art, this invention proposes a plant water, fertilizer, air and heat dynamic regulation system and method based on osmotic potential closed-loop adaptive regulation, which thoroughly solves the above-mentioned technical problems from the aspects of architecture, regulation mechanism and execution unit. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a dynamic regulation system and method for plant water, fertilizer, air, and heat based on osmotic potential closed-loop adaptive regulation. This solves the problems of traditional irrigation relying on manual labor, low water and fertilizer utilization, and inability to accurately match plant needs. Existing technologies lack a reliable dual-closed-loop architecture, have low regulation precision, cannot solve temperature-induced osmotic potential drift, or rely on electricity, are prone to leakage and backflow due to incomplete shut-off, and cannot achieve large-scale, independent, and precise regulation in different zones, making it difficult to adapt to the differentiated cultivation needs of various crops.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a plant water, fertilizer, air, and heat dynamic regulation system based on osmotic potential closed-loop adaptive regulation, comprising:

[0009] include:

[0010] The water potential control container, semi-permeable membrane permeation sensing component, water potential difference driven bidirectional locking switch unit, and water and fertilizer supply unit are sequentially sealed and connected to form an inner closed loop of permeation potential sensing and an outer closed loop of water and fertilizer supply.

[0011] The water potential control container is a cylindrical sealed pressure vessel with a rated pressure of ≥0.3MPa, and has a built-in dual-dimensional collaborative water potential control mechanism. The dual-dimensional collaborative water potential control mechanism includes a concentration adjustment component and a volume temperature compensation component. The concentration adjustment component includes a sealed solute slow-release chamber that is detachably nested in the top liquid inlet of the water potential control container. The bottom of the solute slow-release chamber is provided with a fan-shaped slow-release hole with an adjustable flow area. The arc-shaped adjustment baffle matches the shape of the slow-release hole. The adjustment knob has a range of 0°-90°, corresponding to a linear adjustment of the flow area of ​​0-100%. The top is provided with an adjustment knob that is linked to the arc-shaped adjustment baffle of the slow-release hole. By adjusting the opening of the slow-release hole, the release rate of plant nutrient solutes is controlled, thereby changing the molar concentration of the aqueous solution in the container.

[0012] The volumetric temperature compensation component includes a thermally expanding and contracting filler coaxially nested in the inner wall of the water potential control container and a detachable volume adjustment block fixed inside the container by a slot. The outer wall of the thermally expanding and contracting filler is tightly fitted to the inner wall of the container, and it adaptively adjusts the effective volume of the container through its own thermal expansion and contraction to compensate for the osmotic potential drift caused by environmental temperature fluctuations. The detachable volume adjustment block adjusts the initial effective volume of the container by increasing or decreasing its number. The concentration adjustment component and the volumetric temperature compensation component work together to adjust the reference osmotic potential inside the container to match the optimal water potential requirements of the target plant throughout its entire growth cycle.

[0013] The semi-permeable membrane permeation sensing component is an integrated tubular structure for in-situ sensing and supply in the root zone. Its inlet end is sealed to the bottom outlet of the water potential control container via a UPVC pipe with a one-way valve having an opening pressure of 0.01MPa-0.02MPa. The other end is a closed, embedded end, the outer wall of which is fully covered with a root-penetration-resistant modified semi-permeable membrane. It contains a built-in food-grade polypropylene porous flow-guiding support core with a pore size of 0.1mm-0.5mm and a porosity ≥40%, which is press-fitted and fixed to the inner wall of the modified semi-permeable membrane. The semi-permeable membrane is a cross-linked modified polyvinyl alcohol-polyethersulfone composite membrane with a pore size of 0.001μm-0.01μm, a molecular weight cutoff of 100Da-1000Da, a membrane thickness of 20μm-50μm, a cross-linking degree of ≥85%, and is resistant to root penetration and microbial corrosion, with a service life of ≥24 months. It only allows water molecules and plant nutrient molecules with a molecular weight ≤1000Da to pass through, and is used to establish osmotic potential communication between the inside of the water potential control container and the cultivation substrate in the plant root zone, forming an inner closed loop for osmotic potential sensing.

[0014] The water and fertilizer supply unit is a sealed liquid storage tank with a constant pressure elastic airbag. It is connected to the top liquid replenishment port of the water potential control container via a UPVC pipeline with a one-way valve with an opening pressure of 0.01MPa-0.02MPa. It is used to store nutrient solution with a preset plant nutrient formula and provide water and fertilizer replenishment for the system. The constant pressure elastic airbag is made of neoprene rubber with an elastic coefficient of 0.5N / cm-2.0N / cm.

[0015] The water potential difference driven bidirectional locking switch unit is connected in series on the replenishment pipeline. It is a purely mechanical, non-electric structure, including a valve seat, valve core, return spring, water potential sensing diaphragm, transmission link, and bidirectional locking mechanism. The two ends of the valve seat are sealed to the replenishment pipeline with food-grade silicone O-rings. The edge of the water potential sensing diaphragm is sealed and fixed to the inner wall of the valve seat, dividing the inner cavity of the valve seat into a sensing cavity communicating with the inside of the water potential control container and a flow cavity communicating with the water and fertilizer supply unit. The two ends of the transmission link are coaxially fixed to the center of the water potential sensing diaphragm and the valve core, respectively. The return spring is coaxially sleeved on the outside of the transmission link and located in the sensing cavity. The bidirectional locking mechanism includes a silicone sealing locking ring fixed to the end of the valve core and a limiting groove on the inner wall of the valve seat flow cavity. When the valve is fully closed, the sealing locking ring is interference-fitted into the limiting groove, forming a zero-leakage bidirectional seal with reverse pressure ≥0.2MPa.

[0016] The water potential difference driven bidirectional locking switch unit, water and fertilizer supply unit, and water potential regulation container together form an outer closed loop for water and fertilizer replenishment. Its regulation logic is as follows: when the water potential of the root zone substrate is lower than the reference osmotic potential in the water potential regulation container, water molecules permeate from the container into the root zone substrate through the modified semi-permeable membrane. The water potential in the container drops, forming a negative pressure. The water potential sensing membrane deforms towards the sensing cavity side, driving the valve core to open through the transmission linkage, and the bidirectional locking mechanism unlocks simultaneously. The greater the absolute value of the water potential difference between the root zone substrate and the container, the greater the membrane deformation, the greater the valve opening, and the greater the water and fertilizer replenishment flow rate. When the water potential of the root zone substrate and the reference osmotic potential in the container reach equilibrium, the permeation stops, the negative pressure in the container disappears, the reset spring drives the valve core to reset, the bidirectional locking mechanism locks simultaneously, the valve is completely closed, and water and fertilizer replenishment stops.

[0017] Preferably, the concentration adjustment range of the dual-dimensional synergistic water potential control mechanism is 0.01 mol / L to 1.0 mol / L, corresponding to a reference osmotic potential adjustment range of -0.01 MPa to -1.0 MPa; the reference solute in the solute slow-release chamber is potassium nitrate, and the relationship between concentration and osmotic potential is calibrated using the van der Hoff osmotic pressure formula π=cRT.

[0018] Where π is the osmotic pressure (MPa), c is the molar concentration (mol / L), R is the gas constant (0.008314 L·MPa / (mol·K)), and T is the thermodynamic temperature (K).

[0019] Preferably, the volume adjustment range of the dual-dimensional synergistic water potential control mechanism is 50mL to 5000mL; the thermal expansion and contraction filler is made of food-grade fumed silica gel with a linear expansion coefficient of 2.0×10^-4 / ℃ to 5.0×10^-4 / ℃, and the formula for calculating the volume temperature compensation is:

[0020]

[0021] in To compensate for the volume (mL) The initial effective volume (mL) of the container at a reference temperature of 25°C. The linear expansion coefficient of the filler ( / ℃) is given. The difference (°C) between the ambient temperature and the 25°C reference temperature; the detachable volume adjustment block has four individual volume specifications: 50mL, 100mL, 500mL, and 1000mL.

[0022] Preferably, the response accuracy of the water potential difference driven bidirectional locking switch unit is ≤0.002MPa, and it can operate stably in an ambient temperature range of -20℃ to 60℃; the reset spring is made of 304 stainless steel with a stiffness of 0.2N / mm to 1.0N / mm, and the water potential sensing diaphragm is made of butyl rubber with a thickness of 0.5mm to 1.5mm.

[0023] Preferably, the water and fertilizer supply unit has a built-in two-stage series filtration assembly, with a first-stage filtration accuracy of 1.0μm and a second-stage filtration accuracy of 0.1μm, used to filter impurities and microorganisms in the nutrient solution and prevent the semi-permeable membrane from clogging; the water and fertilizer supply unit has a liquid storage volume of 100mL-10000L, and a top constant pressure elastic airbag maintains the internal pressure at 0.05MPa-0.1MPa.

[0024] Preferably, the system is a large-scale, zoned, independent closed-loop architecture, with each zone corresponding to a cultivation area of ​​more than 1,000 square meters. Multiple zones within the same cultivation environment can be configured with independent dual-closed-loop control systems. The baseline osmotic potential of each system can be independently calibrated without interference, thereby achieving differentiated and precise management of large-scale cultivation zones.

[0025] This invention provides a method for dynamic regulation of plant water, fertilizer, air and heat based on closed-loop adaptive osmotic potential, comprising the following steps:

[0026] S1. Based on the variety, growth stage, and characteristics of the cultivation substrate of the target plant, five groups of gradient water potential treatments were set up, with three biological replicates for each treatment. The net photosynthetic rate, plant height, stem diameter, and root-to-shoot ratio of the target plant were measured through a pot gradient experiment. The optimal water potential threshold was determined by the water potential value with the highest net photosynthetic rate under no drought stress, no waterlogging stress, and a calibration range of -0.01 MPa to -1.0 MPa.

[0027] S2. Based on the calibrated optimal water potential threshold, the concentration of the aqueous solution and the initial effective volume in the water potential control container are adjusted through a dual-dimensional collaborative water potential control mechanism. At the same time, based on the annual temperature fluctuation range of the target cultivation area, a thermal expansion and contraction filler with a corresponding expansion coefficient is matched, and temperature compensation parameters are set so that the reference osmotic potential in the container is precisely matched with the optimal water potential threshold of the target plant.

[0028] S3. The semi-permeable membrane permeation sensing component is embedded in the root zone matrix of the target plant at the same depth as the plant's main root layer. The water potential control container, the water potential difference driven bidirectional locking switch unit, and the water and fertilizer supply unit are sealed and connected using a food-grade silicone O-ring end face to construct a complete closed loop of permeation potential sensing and an external closed loop of water and fertilizer supply.

[0029] S4 All-Environment Adaptive Dynamic Control:

[0030] S4.1 When plant transpiration increases and environmental evaporation increases, causing a decrease in the water potential of the root zone substrate and forming a negative difference with the reference osmotic potential inside the container, water molecules permeate from the container into the root zone substrate through the modified semi-permeable membrane. The water potential inside the container decreases simultaneously, forming a negative pressure. This triggers the water potential difference to drive the bidirectional locking switch unit to unlock and open, and the water and fertilizer supply unit replenishes nutrient solution into the container. The larger the absolute value of the water potential difference, the larger the valve opening and the larger the water and fertilizer supply flow rate, achieving dynamic matching with the plant's water consumption rate.

[0031] S4.2 When plant transpiration weakens and environmental evaporation decreases, the water potential of the root zone substrate rises, and the difference between the water potential and the reference osmotic potential in the container narrows, the negative pressure in the container decreases accordingly, the valve opening decreases accordingly, and the water and fertilizer supply flow rate decreases accordingly.

[0032] S4.3 When the water potential of the root zone substrate reaches equilibrium with the reference osmotic potential inside the container, osmosis stops, the negative pressure inside the container disappears, the water potential difference drives the bidirectional locking switch unit to completely close and bidirectionally lock, stopping water and fertilizer replenishment and maintaining the optimal water, fertilizer and air synergy state of the root zone substrate.

[0033] S5. When the target plant enters a new growth stage, only the solution concentration and volume parameters of the dual-dimensional collaborative water potential regulation mechanism need to be adjusted to match the new water potential requirements, without replacing the main body of the system.

[0034] S6. In large-scale cultivation scenarios, different zones are configured with independent dual-closed-loop control systems according to the variety and growth stage of the crops planted, and each system is preset with matching benchmark osmotic potential parameters. Each system operates independently to achieve precise zone management without interference.

[0035] Preferably, in the potted gradient experiment in step S1, the difference in water potential between adjacent gradients is 0.05MPa-0.1MPa, the experimental period is 15-30 days, the data are analyzed by one-way ANOVA using general statistical software, and multiple comparisons are performed using Duncan's multiple range method, with P<0.05 indicating significant difference.

[0036] Preferably, the method is applicable to large-scale terrestrial plant cultivation scenarios in facility agriculture, landscaping, ecological restoration, and desertification control.

[0037] Beneficial effects

[0038] A search of the closest prior art, including CN101234876A, CN105638456B, and US9872456B2, revealed that the core distinguishing features of this application compared to existing technologies are: a pioneering dual-closed-loop collaborative architecture, a dual-dimensional collaborative water potential control mechanism, and a water potential difference-driven bidirectional locking switch unit. The combination of these features is not disclosed in any prior art and does not offer any technological inspiration, thus demonstrating significant inventiveness.

[0039] This invention provides a plant water, fertilizer, air, and heat dynamic regulation system and method based on osmotic potential closed-loop adaptive regulation. Compared with existing technologies, it has the following advantages:

[0040] This plant water, fertilizer, air and heat dynamic regulation system and method based on osmotic potential closed-loop adaptive is original at the architecture level and completely avoids the scope of existing patent protection: it is the first to create a dual closed-loop collaborative architecture, realizing the decoupled collaboration between osmotic potential sensing and water and fertilizer replenishment, which is completely different from the fixed negative pressure, electronic control sensing and passive water infiltration architecture of existing technologies, and has absolute novelty.

[0041] This invention pioneers a dual-dimensional synergistic water potential regulation mechanism. Through the synergistic effect of concentration regulation and volumetric temperature compensation, it solves the problem of temperature-induced osmotic potential drift, which is unsolvable in existing technologies. The regulation accuracy is improved from ±0.02MPa in existing technologies to ±0.002MPa. This combination is not a simple superposition of conventional technologies in the field, and there is no technological inspiration involved; it possesses significant non-obviousness. This invention is an original technology at the architectural level, completely circumventing the scope of existing patent protection, possessing absolute novelty and significant non-obviousness. Verified by more than three biological replication experiments, the technical effect is stable and reproducible. The specific beneficial effects are as follows:

[0042] Innovative architecture, decoupled collaboration: It is the first to create a dual-closed-loop collaborative architecture of osmotic potential sensing inner closed loop + water and fertilizer replenishment outer closed loop, realizing the decoupled collaboration between real-time sensing of root zone osmotic potential and adaptive water and fertilizer replenishment. It is different from the fixed negative pressure, electronic control sensing and passive water seepage architecture of existing technologies. The control accuracy reaches ±0.002MPa, which is 10 times higher than existing technologies.

[0043] Dual-dimensional regulation solves industry pain points: The first dual-dimensional collaborative water potential regulation mechanism solves the problem of osmotic potential drift caused by environmental temperature fluctuations through the synergistic effect of concentration regulation and volume temperature compensation. The temperature compensation accuracy is improved by more than 90% compared with existing technologies. The dual-dimensional regulation of concentration and volume can match the water potential needs of plants throughout their entire growth cycle without replacing the main system, making it highly adaptable.

[0044] Purely mechanical and electrical-free, zero-leakage locking: The first-ever water potential difference driven bidirectional locking switch unit achieves the synergy of adaptive water potential opening adjustment and bidirectional zero-leakage locking, completely solving the defects of existing technologies such as incomplete shut-off, easy leakage, and easy backflow; the purely mechanical and electrical-free structure is suitable for all scenarios (including no power and extreme environments), with a response accuracy of ≤0.002MPa, reverse pressure resistance ≥0.2MPa, and a service life of ≥10 years.

[0045] Water and fertilizer utilization is greatly improved, and energy saving and environmental protection are achieved: the water utilization rate of this invention reaches more than 98.5%, which saves more than 75% of water compared with flood irrigation and more than 35% of water compared with conventional drip irrigation; the fertilizer utilization rate is increased from the traditional 30% to more than 85%, reducing the amount of chemical fertilizer used by more than 55%, which greatly reduces agricultural non-point source pollution and meets the needs of green agricultural development.

[0046] Modular and scalable with wide adaptability: The system architecture can be modularized and applied on a large scale. A single system can cover a cultivation area of ​​more than 1,000 square meters and support independent closed-loop control of multiple zones. It is suitable for all large-scale terrestrial plant cultivation scenarios such as facility agriculture, landscaping, ecological restoration, and desertification control. It can achieve precise control of different types of plants such as leafy vegetables, strawberries, cucumbers, tomatoes, flowers, and seedlings, without being limited by the type of crop.

[0047] Reduce labor costs and improve cultivation efficiency: No manual intervention is required throughout the entire process, with only simple parameter adjustments made when the plant growth stages change, significantly reducing the number of times manual irrigation and fertilization are carried out; experimental verification has shown that it can significantly improve plant survival rate, seedling strength index, yield and quality, reduce the incidence of diseases and pests, and significantly improve the overall cultivation efficiency. Attached Figure Description

[0048] Figure 1 This is a connection block diagram of the plant water, fertilizer, air and heat dynamic regulation system based on osmotic potential closed-loop adaptive system of the present invention.

[0049] Figure 2This is a flowchart of the plant water, fertilizer, air and heat dynamic regulation method based on osmotic potential closed-loop adaptive method of the present invention.

[0050] Figure 3 This is a flowchart of the adaptive dynamic control method for the entire environment according to the present invention.

[0051] Figure 4 This is a schematic diagram of the structure of the present invention.

[0052] In the diagram: 101, water potential control container; 102, water potential difference driven physical transmission switch unit; 103, semi-permeable membrane permeation component; 104, water and fertilizer supply unit. Detailed Implementation

[0053] The present invention will be further described in detail below with reference to specific embodiments. All embodiments have undergone more than three biological replication experiments with significant differences (P<0.05), and can be completely replicated. The control method of the present invention is manual start / parameter adjustment + mechanical automatic regulation. The wiring of power components and controller programming are common knowledge. The present invention does not involve the improvement of control method and circuit connection, so it will not be described in detail.

[0054] Example 1: Application of strawberry seedling hardening scenario (Verification of lower limit of numerical range)

[0055] System parameter settings

[0056] Water potential control container: rated effective volume 50mL, rated pressure 0.3MPa, initial concentration of 0.01mol / L potassium nitrate solution in the solute slow release chamber (corresponding to reference osmotic potential -0.01MPa), matching the optimal water potential requirements for strawberry hardening; the volume temperature compensation component uses a silicone filler with a linear expansion coefficient of 2.0×10^-4 / ℃, without additional volume adjustment blocks.

[0057] Semi-permeable membrane permeation sensing component: membrane pore size 0.001μm, molecular weight cutoff 100Da, membrane thickness 20μm, crosslinking degree 85%, tubular structure, length 5cm, built-in food-grade polypropylene porous flow-guiding support core (pore size 0.1mm, porosity 40%), embedded 2cm deep in tissue culture matrix.

[0058] Water potential difference driven bidirectional locking switch unit: reset spring stiffness 0.2N / mm, response accuracy ≤0.002MPa.

[0059] Water and fertilizer supply unit: rated volume 100mL, built-in 1.0μm + 0.1μm two-stage filtration, stores 1 / 2 MS nutrient solution, constant pressure elastic air bag is made of neoprene rubber with elasticity coefficient 0.5N / cm, maintains internal pressure of 0.05MPa.

[0060] Test conditions

[0061] Cultivation substrate: peat: perlite = 3:1 mixed substrate; Environmental conditions: light intensity 200 μmol / (m²·s), photoperiod 12h / 12h, ambient humidity 60%-70%, temperature 20℃-25℃.

[0062] Detection methods

[0063] Seedling survival rate: The proportion of surviving plants to the total number of plants is calculated; Contamination rate: The total contamination rate of fungi and bacteria is calculated; Root vigor: Measured using the TTC reduction method; Water use efficiency: The ratio of water consumption by plants to total water supply is calculated.

[0064] Effect verification (25-day hardening-off period, compared with conventional spray hardening-off):

[0065]

[0066] Conclusion: The feasibility and effectiveness of the lower limit of the numerical range of the present invention were verified. The survival rate of strawberry seedlings and root vitality were greatly improved, and the pollution rate was significantly reduced.

[0067] Example 2: Application of Haloxylon ammodendron seedlings in desertification control (Verification of upper limit of numerical range)

[0068] System parameter settings

[0069] Water potential control container: rated effective volume 5000mL, rated bearing pressure 0.5MPa, initial concentration of solute slow release chamber is 1.0mol / L potassium nitrate solution (corresponding to reference osmotic potential -1.0MPa), the volume temperature compensation component adopts a silicone filler with linear expansion coefficient of 5.0×10^-4 / ℃, and is equipped with two 1000mL volume adjustment blocks.

[0070] Semi-permeable membrane permeation sensing component: membrane pore size 0.01μm, molecular weight cutoff 1000Da, membrane thickness 50μm, crosslinking degree 90%, buried structure, length 80cm, built-in food-grade polypropylene porous flow-guiding support core (pore size 0.5mm, porosity 45%), buried 80cm deep in the desert root zone.

[0071] Water potential difference driven bidirectional locking switch unit: reset spring stiffness 1.0N / mm, response accuracy ≤0.002MPa, adaptable to extreme temperatures of -20-60℃.

[0072] Water and fertilizer supply unit: rated volume 10000L, built-in 1.0μm + 0.1μm two-stage filtration, stores Haloxylon ammodendron special nutrient solution, constant pressure elastic air bladder is made of neoprene rubber with an elasticity coefficient of 2.0N / cm, maintaining the internal pressure of 0.1MPa.

[0073] Test conditions

[0074] Cultivation substrate: native sandy soil of the Tengger Desert; Environmental conditions: average annual temperature 8.3℃, extreme maximum temperature 41.7℃, extreme minimum temperature -25.1℃, annual precipitation 180mm.

[0075] Detection methods

[0076] Seedling survival rate: the proportion of surviving seedlings to the total number of seedlings; annual water consumption: the total annual water supply per seedling; seedling height growth: the difference in seedling height before and after the experiment; system fault-free operation time: the time when the system first failed.

[0077] Effectiveness verification (12-month cycle, compared with conventional manual irrigation)

[0078]

[0079] Conclusion: The feasibility and effectiveness of the upper limit of the numerical range of the present invention have been verified. The survival rate of Haloxylon ammodendron seedlings has been greatly improved, water consumption has been significantly reduced, and the system is suitable for complex scenarios of desertification control with no electricity and extreme temperatures. The system has strong stability.

[0080] Example 3: Cucumber seedling cultivation in a greenhouse (verification of the pore size range of a semi-permeable membrane)

[0081] System parameter settings

[0082] The water potential control container has a volume of 1000mL, a rated pressure of 0.3MPa, and an initial concentration of 0.08mol / L potassium nitrate solution (corresponding to an osmotic potential of -0.08MPa) to match the optimal water potential requirements of cucumber seedlings.

[0083] Groups: Treatment group 1 (membrane pore size 0.001μm, molecular weight cutoff 100Da, membrane thickness 30μm, crosslinking degree 88%), Treatment group 2 (membrane pore size 0.01μm, molecular weight cutoff 1000Da, membrane thickness 30μm, crosslinking degree 88%), and control group (conventional drip irrigation); The semi-permeable membrane permeation sensing component has a built-in food-grade polypropylene porous flow-guiding support core (pore size 0.2mm, porosity 42%), buried 10cm deep in the root zone, and the water and fertilizer supply unit stores special nutrient solution for cucumber seedlings.

[0084] Test conditions

[0085] Cultivation substrate: Peat moss: Vermiculite = 2:1 mixed substrate; Environmental conditions: Light intensity 300 μmol / (m²·s), photoperiod 14h / 10h, ambient humidity 65%-75%, temperature 22℃-28℃.

[0086] Detection methods

[0087] Membrane blockage rate: The proportion of blocked membrane tubes to the total number of membrane tubes; Seedling strength index: Calculated by the formula (stem diameter / plant height) × total dry weight of the plant; Water use efficiency: Calculated by the ratio of plant water consumption to total water supply.

[0088] Effectiveness verification (30-day cycle)

[0089]

[0090] Conclusion: The feasibility of the invention by touching the two ends of the aperture range was verified. Both treatments significantly improved the seedling vigor index and water use efficiency of cucumber seedlings, with extremely low membrane blockage rate, making it suitable for greenhouse vegetable cultivation.

[0091] Example 4: Specific verification of temperature compensation function (verification of core invention points)

[0092] The verification method is based on the osmotic potential temperature correction formula π=cRT and the volume compensation calculation formula ΔV=V0×α×ΔT. At four temperature points of 5℃, 25℃, 45℃ and 60℃, the volume compensation and osmotic potential deviation of the uncompensated group and the group with a linear expansion coefficient of 3.0×10^-4 / ℃ are measured to verify the accuracy of temperature compensation.

[0093] Verification results

[0094]

[0095] Conclusion: The temperature compensation component of the present invention can effectively compensate for the osmotic potential drift caused by ambient temperature fluctuations, and the compensation accuracy is improved by more than 90% compared with the prior art, completely solving the industry pain point of temperature-induced osmotic potential drift.

[0096] Example 5:

[0097] Large-scale cultivation of tomatoes throughout their entire growth cycle in a solar greenhouse (2000㎡, zoned control verification).

[0098] System parameter settings

[0099] Cultivation scale: 2000㎡ solar greenhouse, divided into 2 independent zones, each equipped with 1 set of the invention system, with each system covering 1000㎡.

[0100] Water potential control container: single set volume 5000mL, rated pressure 0.4MPa, the baseline osmotic potential is adjusted according to different growth stages of tomatoes: seedling stage -0.05MPa, flowering and fruit setting stage -0.08MPa, fruit expansion stage -0.12MPa, harvest stage -0.15MPa.

[0101] Semi-permeable membrane permeation sensing component: membrane pore size 0.005μm, molecular weight cutoff 500Da, membrane thickness 35μm, crosslinking degree 87%, buried structure, buried 15cm deep in the root zone along the cultivation ridge, with a spacing of 30cm, and built-in food-grade polypropylene porous flow-guiding support core (pore size 0.3mm, porosity 43%).

[0102] Water and fertilizer supply unit: single unit volume 5000L, built-in 1.0μm + 0.1μm two-stage filtration, stores special nutrient solution for the whole cycle of tomatoes, constant pressure elastic air bag is made of neoprene rubber with elasticity coefficient 1.2N / cm, maintains the internal pressure of 0.08MPa.

[0103] Test conditions

[0104] Cultivation substrate: Conventional cultivation substrate for greenhouse (organic fertilizer: garden soil = 1:3); Environmental conditions: light intensity 400 μmol / (m²·s), photoperiod 14h / 10h, ambient humidity 60%-80%, temperature 18℃-30℃.

[0105] Detection methods

[0106] Yield per mu: The total yield of the statistical zone was converted into yield per mu; Soluble solids content of fruit: Measured using a handheld refractometer; Water use efficiency: The ratio of total water consumption to total yield of the zone was calculated; Fertilizer use efficiency: The ratio of nutrient absorption by the plant to total fertilizer application was calculated; Disease and pest incidence rate: The total incidence rate of gray mold, aphids, and whiteflies was statistically analyzed; Number of manual interventions: The number of manual operations throughout the entire growth cycle was statistically analyzed.

[0107] Effectiveness verification (full growth cycle, compared with conventional drip irrigation)

[0108]

[0109] Conclusion: This invention is applicable to large-scale facility agriculture cultivation, enabling precise control of the entire tomato growth cycle, significantly improving yield, quality, and water and fertilizer utilization, reducing the incidence of pests and diseases and labor costs, and achieving large-scale differentiated management through a zoned, independent closed-loop structure, resulting in a significant improvement in overall cultivation benefits. Attached Figure Description

[0110] Figure 1 This is a connection block diagram of the plant water, fertilizer, air and heat dynamic regulation system based on osmotic potential closed-loop adaptive system of the present invention.

[0111] Figure 2 This is a flowchart of the plant water, fertilizer, air and heat dynamic regulation method based on osmotic potential closed-loop adaptive method of the present invention.

[0112] Figure 3 This is a flowchart of the sub-steps of the all-environment adaptive dynamic control of the present invention;

[0113] Figure 4 This is a schematic diagram of the core structure of the system of the present invention;

[0114] Explanation of reference numerals in the attached drawings: 101-Water potential control container, 102-Dual-dimensional collaborative water potential control mechanism, 103-Semi-permeable membrane permeation sensing component, 104-Water potential difference driven bidirectional locking switch unit, 105-Water and fertilizer supply unit.

[0115] The scope of protection of this invention includes any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention; the technical features of this invention can be reasonably combined, and all combinations fall within the scope of protection of this invention.

Claims

1. A plant water, fertilizer, air, and heat dynamic regulation system based on osmotic potential closed-loop adaptive regulation, characterized in that, include: A water potential control container (101), a semi-permeable membrane permeation sensing component (103), a water potential difference driven bidirectional locking switch unit (104), and a water and fertilizer supply unit (105) are sequentially sealed and connected to form an inner closed loop of permeation potential sensing and an outer closed loop of water and fertilizer supply. The water potential control container (101) is a cylindrical sealed pressure-bearing container with a rated pressure of ≥0.3MPa, and has a built-in dual-dimensional collaborative water potential control mechanism (102). The dual-dimensional collaborative water potential control mechanism (102) includes a concentration adjustment component and a volume temperature compensation component. The concentration adjustment component includes a sealed solute slow release chamber that can be detachably nested in the top liquid inlet of the water potential control container (101). The bottom of the solute slow release chamber is provided with a fan-shaped slow release hole with an adjustable flow area. The arc-shaped adjustment baffle matches the shape of the slow release hole. The adjustment knob has a range of 0°-90°, corresponding to a linear adjustment of the flow area of ​​0-100%. The top is provided with an adjustment knob that is linked to the arc-shaped adjustment baffle of the slow release hole. By adjusting the opening of the slow release hole, the release rate of plant nutrient solute is controlled, thereby changing the molar concentration of the aqueous solution in the container. The volumetric temperature compensation component includes a thermally expanding and contracting filler coaxially nested in the inner wall of the water potential control container (101) and a detachable volume adjustment block fixed inside the container in a slot. The outer wall of the thermally expanding and contracting filler is tightly sealed to the inner wall of the container, and the effective volume of the container is adaptively adjusted by its own thermal expansion and contraction to compensate for the osmotic potential drift caused by environmental temperature fluctuations. The initial effective volume of the container is adjusted by increasing or decreasing the number of the detachable volume adjustment blocks. The concentration adjustment component and the volumetric temperature compensation component work together to adjust the reference osmotic potential inside the container to match the optimal water potential requirements of the target plant throughout its entire growth cycle. The semi-permeable membrane permeation sensing component (103) is an integrated tubular structure for in-situ sensing and supply in the root zone. Its inlet end is sealed and connected to the bottom outlet of the water potential control container (101) via a UPVC pipe with an opening pressure of 0.01MPa-0.02MPa one-way valve. The other end is a closed embedded end, the outer wall of which is fully covered with a root-penetration-resistant modified semi-permeable membrane. It has a built-in food-grade polypropylene porous flow-guiding support core with a pore size of 0.1mm-0.5mm and a porosity of ≥40%, which is press-fitted and fixed to the inner wall of the modified semi-permeable membrane. The modified semipermeable membrane is a cross-linked modified polyvinyl alcohol-polyethersulfone composite membrane with a pore size of 0.001μm-0.01μm, a molecular weight cutoff of 100Da-1000Da, a membrane thickness of 20μm-50μm, a cross-linking degree of ≥85%, and is resistant to root penetration and microbial corrosion, with a service life of ≥24 months. It only allows water molecules and plant nutrient molecules with a molecular weight of ≤1000Da to pass through, and is used to establish osmotic potential communication between the interior of the water potential control container (101) and the plant root zone cultivation substrate, forming an inner closed loop for osmotic potential sensing. The water and fertilizer supply unit (105) is a sealed liquid storage tank with a constant pressure elastic airbag. It is connected to the top liquid replenishment port of the water potential control container (101) through a UPVC pipeline with a one-way valve with an opening pressure of 0.01MPa-0.02MPa. It is used to store nutrient solution with a preset plant nutrient formula and provide water and fertilizer supply to the system. The constant pressure elastic airbag is made of neoprene rubber with an elastic coefficient of 0.5N / cm-2.0N / cm. The water potential difference driven bidirectional locking switch unit (104) is connected in series on the replenishment pipeline. It is a purely mechanical and non-electric structure, including a valve seat, valve core, return spring, water potential sensing diaphragm, transmission link, and bidirectional locking mechanism. The two ends of the valve seat are sealed to the replenishment pipeline with food-grade silicone O-rings. The edge of the water potential sensing diaphragm is sealed and fixed to the inner wall of the valve seat, dividing the inner cavity of the valve seat into a sensing cavity that communicates with the inside of the water potential control container and a flow cavity that communicates with the water and fertilizer supply unit (105). The two ends of the transmission link are coaxially fixed to the center of the water potential sensing diaphragm and the valve core, respectively. The return spring is coaxially sleeved on the outside of the transmission link and located in the sensing cavity. The bidirectional locking mechanism includes a silicone sealing locking ring fixed to the end of the valve core and a limiting groove on the inner wall of the valve seat flow cavity. When the valve is completely closed, the sealing locking ring is interference-fitted into the limiting groove to form a zero-leakage bidirectional seal with reverse pressure ≥0.2MPa. The water potential difference driven bidirectional locking switch unit (104), water and fertilizer supply unit (105), and water potential control container (101) together constitute an outer closed loop for water and fertilizer replenishment. The control logic is as follows: when the water potential of the root zone substrate is lower than the reference osmotic potential in the water potential control container (101), water molecules permeate from the container to the root zone substrate through the modified semi-permeable membrane. The water potential in the container drops, forming a negative pressure. The water potential sensing membrane deforms towards the sensing cavity side, and drives the valve core to open through the transmission linkage. The bidirectional locking mechanism unlocks simultaneously. The greater the absolute value of the water potential difference between the root zone substrate and the container, the greater the membrane deformation, the greater the valve opening, and the greater the water and fertilizer replenishment flow rate. When the water potential of the root zone substrate and the reference osmotic potential in the container reach equilibrium, the permeation stops, the negative pressure in the container disappears, the reset spring drives the valve core to reset, the bidirectional locking mechanism locks simultaneously, the valve is completely closed, and water and fertilizer replenishment stops.

2. The plant water, fertilizer, air, and heat dynamic regulation system based on closed-loop adaptive osmotic potential according to claim 1, characterized in that: The concentration adjustment range of the dual-dimensional collaborative water potential control mechanism is 0.01 mol / L to 1.0 mol / L, corresponding to a reference osmotic potential adjustment range of -0.01 MPa to -1.0 MPa. The reference solute in the solute slow-release chamber is potassium nitrate, and the relationship between concentration and osmotic potential is calibrated using the van der Hoff osmotic pressure formula π=cRT. Where π is the osmotic pressure (MPa), c is the molar concentration (mol / L), R is the gas constant (0.008314 L·MPa / (mol·K)), and T is the thermodynamic temperature (K).

3. The plant water, fertilizer, air, and heat dynamic regulation system based on closed-loop adaptive osmotic potential according to claim 1, characterized in that: The volume adjustment range of the dual-dimensional collaborative water potential control mechanism is 50mL to 5000mL; the thermal expansion and contraction filler is made of food-grade fumed silica gel with a linear expansion coefficient of 2.0×10^-4 / ℃ to 5.0×10^-4 / ℃, and the formula for calculating the volume temperature compensation is: in To compensate for the volume (mL) The initial effective volume (mL) of the container at a reference temperature of 25°C. The linear expansion coefficient of the filler ( / ℃) is given. The difference (°C) between the ambient temperature and the 25°C reference temperature; the detachable volume adjustment block has four individual volume specifications: 50mL, 100mL, 500mL, and 1000mL.

4. The plant water, fertilizer, air, and heat dynamic regulation system based on closed-loop adaptive osmotic potential according to claim 1, characterized in that: The response accuracy of the water potential difference driven bidirectional locking switch unit (104) is ≤0.002MPa, and it can operate stably in an ambient temperature range of -20℃ to 60℃; the reset spring is made of 304 stainless steel with a stiffness of 0.2N / mm to 1.0N / mm, and the water potential sensing diaphragm is made of butyl rubber with a thickness of 0.5mm to 1.5mm.

5. The plant water, fertilizer, air, and heat dynamic regulation system based on closed-loop adaptive osmotic potential according to claim 1, characterized in that: The water and fertilizer supply unit (105) has a built-in two-stage series filtration assembly. The first stage has a filtration accuracy of 1.0μm and the second stage has a filtration accuracy of 0.1μm. It is used to filter impurities and microorganisms in the nutrient solution and prevent the semi-permeable membrane from clogging. The water and fertilizer supply unit (105) has a liquid storage volume of 100mL-10000L. The top constant pressure elastic airbag maintains the pressure inside the chamber at a stable level of 0.05MPa-0.1MPa.

6. The plant water, fertilizer, air, and heat dynamic regulation system based on closed-loop adaptive osmotic potential according to claim 1, characterized in that: The system is a large-scale, zoned, independent closed-loop architecture. Each zone corresponds to a cultivation area of ​​more than 1,000 square meters. Multiple zones within the same cultivation environment can be configured with independent dual-closed-loop control systems. The baseline osmotic potential of each system can be independently calibrated without interference, thus achieving differentiated and precise management of large-scale cultivation zones.

7. A method for dynamic regulation of plant water, fertilizer, air, and heat based on closed-loop adaptive osmotic potential, characterized in that, Using the system according to any one of claims 1-6 includes the following steps: S1. Based on the variety, growth stage, and characteristics of the cultivation substrate of the target plant, five groups of gradient water potential treatments were set up, with three biological replicates for each treatment. The net photosynthetic rate, plant height, stem diameter, and root-to-shoot ratio of the target plant were measured through a pot gradient experiment. The optimal water potential threshold was determined by the water potential value with the highest net photosynthetic rate under no drought stress, no waterlogging stress, and a calibration range of -0.01 MPa to -1.0 MPa. S2. Based on the calibrated optimal water potential threshold, the concentration of the aqueous solution and the initial effective volume in the water potential control container are adjusted through a dual-dimensional collaborative water potential control mechanism. At the same time, based on the annual temperature fluctuation range of the target cultivation area, a thermal expansion and contraction filler with a corresponding expansion coefficient is matched, and temperature compensation parameters are set so that the reference osmotic potential in the container is precisely matched with the optimal water potential threshold of the target plant. S3. The semi-permeable membrane permeation sensing component is embedded in the root zone matrix of the target plant at the same depth as the plant's main root layer. The water potential control container, the water potential difference driven bidirectional locking switch unit, and the water and fertilizer supply unit are sealed and connected using a food-grade silicone O-ring end face to construct a complete closed loop of permeation potential sensing and an external closed loop of water and fertilizer supply. S4 All-Environment Adaptive Dynamic Control: S4.1 When plant transpiration increases and environmental evaporation increases, causing a decrease in the water potential of the root zone substrate and forming a negative difference with the reference osmotic potential inside the container, water molecules permeate from the container into the root zone substrate through the modified semi-permeable membrane. The water potential inside the container decreases simultaneously, forming a negative pressure. This triggers the water potential difference to drive the bidirectional locking switch unit to unlock and open, and the water and fertilizer supply unit replenishes nutrient solution into the container. The larger the absolute value of the water potential difference, the larger the valve opening and the larger the water and fertilizer supply flow rate, achieving dynamic matching with the plant's water consumption rate. S4.2 When plant transpiration weakens and environmental evaporation decreases, the water potential of the root zone substrate rises, and the difference between the water potential and the reference osmotic potential in the container narrows, the negative pressure in the container decreases accordingly, the valve opening decreases accordingly, and the water and fertilizer supply flow rate decreases accordingly. S4.3 When the water potential of the root zone substrate reaches equilibrium with the reference osmotic potential inside the container, osmosis stops, the negative pressure inside the container disappears, the water potential difference drives the bidirectional locking switch unit to completely close and bidirectionally lock, stopping water and fertilizer replenishment and maintaining the optimal water, fertilizer and air synergy state of the root zone substrate. S5. When the target plant enters a new growth stage, only the solution concentration and volume parameters of the dual-dimensional collaborative water potential regulation mechanism need to be adjusted to match the new water potential requirements, without replacing the main body of the system. S6. In large-scale cultivation scenarios, different zones are configured with independent dual-closed-loop control systems according to the variety and growth stage of the crops planted, and each system is preset with matching benchmark osmotic potential parameters. Each system operates independently to achieve precise zone management without interference.

8. The method for dynamic regulation of plant water, fertilizer, air, and heat based on closed-loop adaptive osmotic potential according to claim 7, characterized in that: In the potted gradient experiment in step S1, the difference in water potential between adjacent gradients was 0.05 MPa-0.1 MPa, the experimental period was 15-30 days, and the data were analyzed by one-way ANOVA using general statistical software and multiple comparisons were performed using Duncan's multiple range method. P<0.05 was considered significant.

9. The method for dynamic regulation of plant water, fertilizer, air, and heat based on closed-loop adaptive osmotic potential according to claim 7, characterized in that: The method is applicable to large-scale terrestrial plant cultivation scenarios in facility agriculture, landscaping, ecological restoration, and desertification control.

Images