An intelligent irrigation and salt regulation integrated system for cotton saline-alkali land improvement

Abstract

The present application relates to the technical field of agricultural engineering, in particular to a kind of intelligent irrigation and salt control integrated system for cotton saline-alkali land improvement, comprising several irrigation pipes, several branch pipes are communicated on the irrigation pipe, several adjusting devices are also sleeved on the irrigation pipe, adjusting device all includes several levels of first and last sleeved support rods, water inlet for making brine enter the inside of support rod is opened in the inside of support rod near bottom end, buoyancy unfolding mechanism for driving next level support rod vertical unfolding by brine injection is all arranged in the inside of support rod, conversion component for switching branch pipe drainage aperture according to support rod lifting height is all arranged between irrigation pipe and last level support rod.The present application automatically switches branch pipe drainage aperture by the linkage of conversion component of buoyancy unfolding mechanism of multistage support rod in adjusting device, in combination with irrigation control system real-time sensing and dynamic strategy, realize the whole cycle automatic salt control and precision irrigation of cotton saline-alkali land winter salt water uniform spreading ice, spring under-membrane drip irrigation salt prevention.

Description

Technical Field

[0001] This invention relates to the field of agricultural engineering technology, specifically to an integrated intelligent irrigation and salinity control system for improving cotton-growing saline-alkali land. Background Technology

[0002] Saline-alkali land is widely distributed globally, and my country also has a considerable amount of saline-alkali land resources. Due to the excessively high salt content in saline-alkali soil, cotton growth is inhibited, resulting in low germination rates, slow growth, and even death, severely limiting the agricultural value of the land. Improving saline-alkali land has become a key task in agricultural development to enhance land productivity. Currently, using saline-alkali water and ice layers for cotton improvement is an effective method. The principle is that saline water is irrigated into cotton fields in winter, freezing at low temperatures. In spring, as temperatures rise, the ice melts, and the highly concentrated saline water seeps down, carrying away some of the salt. Subsequent melting of slightly brackish and fresh water further leaches the soil, causing salt to migrate to deeper soil layers, thereby reducing the salt content in the surface soil and creating suitable conditions for crop growth.

[0003] The literature "Research Progress and Prospect of Saltwater Irrigation for Saline-Alkali Land Improvement" points out that highly mineralized saline water cannot be directly used for irrigation due to its high salt content. Therefore, how to rationally utilize this highly mineralized groundwater for saline-alkali land improvement is an urgent problem to be solved in agricultural production in this region. Based on this background, this paper proposes a winter saline water freezing irrigation technology for improving saline-alkali land, based on regional climate conditions, soil water and salt transport patterns, and plant growth and development patterns, and the principle of saline-alkali water separation during freezing and thawing. This technology makes full use of the region's low winter temperatures and abundant saline water resources. In winter, the saline-alkali land is irrigated with frozen water. During the melting of the ice, the slightly saline water and fresh water released have a good leaching effect on soil salt. Combined with subsequent salt suppression measures and summer rainfall leaching, low-salt soil conditions are created for crop emergence and plant growth.

[0004] However, existing technologies for improving saline-alkali land using saline water and ice layers have many drawbacks. When using saline water, large-scale flushing of brine is typically performed in winter, attempting to freeze the brine on the soil surface for subsequent improvement. However, in practice, flushing with water makes it difficult to distribute the brine evenly across the soil surface, requiring significant manpower to manually sweep the brine to ensure a relatively uniform salt distribution. This not only results in high labor costs but also low efficiency. Furthermore, manual sweeping is rarely completely uniform, leading to uneven soil salinity and affecting the effectiveness of subsequent improvement efforts. Therefore, there is an urgent need to develop an integrated intelligent irrigation and salinity control system for saline-alkali land improvement. Summary of the Invention

[0005] To address the aforementioned issues, this invention provides an integrated intelligent irrigation and salinity control system for improving saline-alkali land used for cotton cultivation. The system utilizes a multi-stage support rod buoyancy deployment mechanism linked to a conversion component in the irrigation pipe's adjustment device to automatically switch the branch pipe drainage hole diameter. Combined with real-time sensing and dynamic strategies from the irrigation control system, it achieves fully automated salinity control and precise irrigation throughout the entire cycle, ensuring uniform freezing of saline water in winter and preventing salt backflow during spring drip irrigation under mulch.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: An integrated intelligent irrigation and salinity control system for improving saline-alkali land for cotton cultivation includes several irrigation pipes and a variable frequency water pump. The irrigation pipes are all connected to the variable frequency water pump, and several branch pipes are connected to the irrigation pipes. Each irrigation pipe is equipped with a solenoid valve, and a partition valve is provided at the connection between the solenoid valve and the irrigation pipe. The solenoid valve signal is connected to an irrigation control system. Several adjusting devices are also sleeved on the irrigation pipes. Each adjusting device includes several levels of support rods that are sleeved end to end. Each support rod has an inlet near the bottom end to allow brine to enter the support rod. Each support rod is equipped with a buoyancy deployment mechanism for driving the next level support rod to deploy vertically by injecting brine. A conversion component is provided between the irrigation pipe and the last level support rod for switching the drainage hole diameter at the branch pipe according to the lifting height of the support rod.

[0007] Each conversion assembly includes a first fixing block fixedly connected to the outer wall of any first-level support rod. A crank-connecting rod mechanism is hinged to the first fixing block. A conversion ring is hinged to the end of the crank-connecting rod mechanism away from the first fixing block. The conversion ring is sleeved on the branch pipe and rotatably connected to the branch pipe. Each branch pipe has a water outlet hole. The conversion ring is divided into a water injection area and a drip irrigation area. The water injection area has only a single first hole, and the drip irrigation area has several second holes. A pressure compensation diaphragm is provided on the inner wall of the drip irrigation area. The diameter of the water outlet hole is greater than or equal to the diameter of the first hole and greater than the diameter of the second hole.

[0008] The technical principles of the above solution are as follows:

[0009] When irrigation begins, the irrigation control system opens the solenoid valve and zone valve, and the variable frequency water pump delivers brine to the irrigation pipe and branch pipe. At this time, the drip irrigation zone of the switching ring aligns with the outlet of the branch pipe, and several second holes in the drip irrigation zone work with the pressure compensation diaphragm to discharge water at a low to medium flow rate and high velocity.

[0010] As brine is continuously injected, some of it enters the interior through the inlet of the support rod, triggering the buoyancy deployment mechanism. The float at the bottom of the next-level support rod rises under the buoyancy of the brine, causing the next-level support rod to deploy vertically from the top of the previous level, and so on, with each level of support rod deploying sequentially. During this process, when the support rod rises to a certain height, a conversion component aligns the water injection area with the outlet of the branch pipe. The single first hole in the water injection area increases the water injection volume, rapidly forming an 18-21 cm layer of brine ice, accelerating the ice formation process.

[0011] As the brine melts and seeps down in spring, the ice layer inside the support rods disappears, the buoyancy deployment mechanism loses buoyancy, and each support rod retracts sequentially under gravity. Simultaneously, the crank-connecting rod mechanism drives the conversion ring to rotate in the opposite direction, aligning the drip irrigation area with the outlet hole again, and the system switches to low-flow drip irrigation mode.

[0012] The above approach has the following beneficial effects:

[0013] 1. This solution utilizes a buoyancy-driven deployment mechanism to progressively raise the support rod, which in turn activates a switching component to change the drainage orifice diameter. Based on salinity control requirements, a large-orifice-diameter switching mechanism, combined with a pressure-compensating diaphragm, precisely controls the water flow, ensuring uniform distribution of saline water and rapid ice formation. This achieves adaptive switching between "high-speed water spreading with small orifices" and "rapid ice injection with large orifices." The brine expands uniformly under the support of the ice layer, and the irrigation pipe detaches from the ice surface as the support rod rises, completely avoiding the risk of freezing and significantly improving ice formation efficiency.

[0014] 2. In spring, the system automatically switches to low-flow drip irrigation mode based on the natural contraction of the support rods, dynamically adapting to irrigation needs at different stages and effectively suppressing salt backflow. Simultaneously, the contracted support rods bring the irrigation pipes closer to the soil surface, ensuring that the irrigation pipes are always located under the mulch film during mulching. This subsurface drip irrigation effectively blocks water evaporation. The mechanical structure and salt control logic are deeply coupled, forming a closed-loop control system of "ice melting - mulching for salt suppression - subsurface drip irrigation," requiring no external intervention.

[0015] Furthermore, elastic sealing strips are provided around both the conversion ring and the branch pipe, and these elastic sealing strips are used to seal and separate the water injection area and the drip irrigation area.

[0016] Beneficial effects: When draining water from the drip irrigation area, the elastic sealing strip blocks the passage of the water injection area, preventing brine from leaking from the water injection area, ensuring the high flow rate and low flow characteristics under the action of the pressure compensation diaphragm, and achieving uniform and rapid spread of saline water in winter.

[0017] Furthermore, each buoyancy deployment mechanism includes a float fixedly connected to the bottom of the next-level support rod. Each support rod has an opening at its top, and a sealing ring is fixedly connected inside the opening. The next-level support rod is slidably connected to the sealing ring when it is deployed or retracted.

[0018] Beneficial effects: Utilizing the buoyancy of brine injection as the driving force, the float at the bottom of the next-level support rod automatically rises with the liquid level, allowing the support rod to be vertically deployed step by step without the need for an additional power device; the sealing ring at the top of each support rod is slidably connected to the next level support rod, ensuring smooth deployment and retraction while isolating the internal and external spaces of the support rod to prevent brine leakage from the connection point during vertical deployment, thus ensuring the stability of buoyancy-driven operation; after the ice melts in spring, the support rod retracts under gravity, and the sliding fit of the sealing ring prevents jamming, ensuring that the switching component accurately switches to drip irrigation mode as the support rod retracts.

[0019] Furthermore, several storage slots are opened at the ends of the support rods, and a second fixing block is fixedly connected in each storage slot. A first connecting plate and a second connecting plate are respectively hinged to the second fixing block. An arc-shaped slide rail is opened on the bottom wall of the irrigation pipe. A first slider and a second slider are respectively hinged to the ends of the first connecting plate and the second connecting plate away from the second fixing block. The first slider and the second slider are both located in the arc-shaped slide rail and slide in cooperation with the arc-shaped slide rail.

[0020] Beneficial effects: The first and second connecting plates, hinged to the second fixing block, form a four-bar linkage support mechanism with the slider inside the arc-shaped slide rail of the irrigation pipe. When the support rod is vertically extended, the connecting plates unfold from the storage groove, and the lifting force of the support rod is evenly transmitted to the bottom of the irrigation pipe through the sliding of the first and second sliders within the arc-shaped slide rail. This multi-point support structure avoids the tilting or displacement of the irrigation pipe that may be caused by traditional single-point support, ensuring precise alignment between the branch pipe outlet and the conversion ring.

[0021] Furthermore, each of the arc-shaped slide rails is equipped with a damping component to reduce the impact when the first connecting plate and the second connecting plate expand or contract. Each damping component includes a first spring and a second spring. The two ends of the first spring are fixedly connected between the first slider and the second slider, respectively, and the two ends of the second spring are fixedly connected to the second slider and the side wall of the arc-shaped slide rail, respectively.

[0022] Beneficial effects: Through the combined action of the first and second springs, the impact force caused by the instantaneous vertical expansion or contraction of the first and second sliders within the arc-shaped slide rail can be suppressed, thus preventing damage to the irrigation pipe.

[0023] Furthermore, the inner walls of the irrigation pipes, branch pipes, and support rods are coated with a fusion-bonded epoxy powder coating and a polyethylene coating from the inside out.

[0024] Beneficial effects: The fusion-bonded epoxy powder coating has extremely strong chemical stability, which can effectively resist the erosion of high concentrations of salt and acid and alkali substances in saline-alkali land, forming the first anti-corrosion barrier; the outer polyethylene coating further isolates moisture and air, preventing coating aging and penetration. The dual protection significantly extends the service life of the equipment by improving the corrosion resistance of the pipe and avoiding the impact of pipeline corrosion and leakage on irrigation and salt control effects.

[0025] Furthermore, each branch pipe is embedded with symmetrically arranged magnetic positioning plates, and each conversion ring is embedded with an iron induction plate corresponding to the magnetic positioning plates.

[0026] Beneficial effects: When the switching ring rotates to change the drainage hole diameter, the iron sensing plate will be attracted by magnetic force when it approaches the magnetic positioning plate, accurately positioning itself in the preset position and avoiding positional deviation caused by mechanical errors or water flow impact. When the switching ring rotates to the correct position and the iron sensing plate and magnetic positioning plate are fully aligned, a specific magnetic field change signal will be generated and transmitted to the irrigation control system. The system uses this signal to determine whether the switching component is in the correct working state. If the expected signal is not detected, a fault warning can be issued in time.

[0027] Furthermore, the irrigation control system includes a sensing unit, a data acquisition and processing module, a strategy generation module, and an execution control module, wherein:

[0028] The sensing unit is connected to the variable frequency water pump, solenoid valve and iron induction plate respectively. The sensing unit includes several soil sensors, flow rate sensors and displacement sensors installed on the irrigation pipe and support rod. The sensing unit transmits data from the sensors through several paths to the data acquisition module.

[0029] The data acquisition module is used to receive data from the sensing unit, including the frequency of the variable frequency water pump, the opening degree of the solenoid valve, the position of the switching ring, the soil salt concentration, the soil surface temperature, the soil surface humidity, the water flow rate in the irrigation pipe, and the vertical extension height of the support rod. The module then uses data filtering and normalization to obtain the processed environmental dataset and equipment dataset, which are then transmitted to the strategy generation module and the execution control module, respectively.

[0030] The strategy generation module receives environmental and equipment datasets, calculates the ice formation rate by extracting soil surface temperature and vertical extension height of support rods, and generates water injection adjustment instructions; it obtains dynamic salt concentration values ​​by extracting soil salt concentration, matches drip irrigation rates based on dynamic salt concentration values ​​and soil surface moisture, and transmits water injection adjustment instructions and drip irrigation rates to the execution control module.

[0031] The execution control module is used to receive water injection volume adjustment commands and drip irrigation rates. By extracting real-time variable frequency pump frequency, solenoid valve opening, switching ring position data and water flow rate data for comparison, it controls and adjusts the variable frequency pump frequency and solenoid valve opening according to the water injection volume adjustment commands and drip irrigation rates.

[0032] Furthermore, the strategy generation module includes an ice layer construction control unit, which calculates the ice layer thickness using the ice layer growth rate formula based on the vertical deployment height data of the support rods and the soil surface temperature data.

[0033]

[0034] V1 = K*(Hh / T)

[0035] Where V0 represents the freezing rate in the range where the ice thickness is less than 2-3 cm, K is a correction factor, T0 is the freezing point temperature, and T s The soil surface temperature is t, and the real-time water injection time is t. The freezing rate is calculated when the ice layer thickness reaches 2-3 cm. When the freezing rate is lower than the set threshold, the water injection volume adjustment command is generated and transmitted to the execution control module.

[0036] V1 represents the icing rate when the ice thickness is greater than 2-3cm, H represents the vertical deployment height data, h represents the initial height difference between the displacement sensor and the ground, and T is the current temperature. By calculating the icing rate when the ice thickness is greater than 2-3cm, when the icing rate is lower than the set threshold, a water injection adjustment command to increase the water injection volume is generated and transmitted to the execution control module; when the ice thickness Hh is between 20cm and 25cm, a water injection adjustment command to shut off the water injection volume is generated and transmitted to the execution control module.

[0037] Furthermore, the strategy generation module also includes a drip irrigation control unit, which is used to receive soil salinity C. s A gradient dilution model is used:

[0038] Q = Q0 * (C s / C max ) n

[0039] Where Q0 is the baseline drip irrigation volume, and C max Where C is the upper limit of salt concentration, n is the dilution gradient coefficient, and C is the upper limit of salt concentration. s ≥C max At that time, the target drip irrigation volume is calculated through the gradient dilution model, and the drip irrigation rate is generated and sent to the execution control module. The execution control module generates a speed adjustment command and transmits it to the variable frequency water pump to adjust the water flow.

[0040] Beneficial effects: 1. The sensing unit integrates multiple types of sensors, including soil, flow velocity, and displacement sensors, to capture environmental and equipment status data in real time, covering key indicators such as soil salinity, ice growth, and water flow velocity. Compared to traditional single-point monitoring, the system, through the data acquisition and processing module's fusion analysis of multi-source information, can accurately depict the changes throughout the entire cycle of saline-alkali land improvement, providing a comprehensive basis for decision-making and avoiding control delays or errors caused by monitoring blind spots.

[0041] 2. The strategy generation module incorporates an ice layer growth rate model and a gradient dilution algorithm, dynamically calculating the injection volume and drip irrigation rate based on real-time data. For example, through the two-stage formula of the ice layer construction control unit, the system can precisely control the freezing process according to soil temperature and support rod height. When the freezing rate is lower than the threshold, the injection volume is automatically increased to ensure that the ice layer thickness meets the standard. The drip irrigation control unit adjusts the drip irrigation volume according to the soil salt concentration gradient, making salt dilution more uniform and efficient.

[0042] 3. The execution control module compares the strategy commands with the real-time status of the equipment and dynamically adjusts the opening of the variable frequency water pump and solenoid valve. For example, when the orifice diameter is switched by the conversion ring, the system can verify whether the orifice diameter switch is in place by using the position signals fed back by the iron induction plate and the magnetic positioning plate. If a deviation occurs, it will be corrected immediately to avoid irrigation failure due to mechanical failure or environmental interference.

[0043] 4. From winter ice layer formation to spring drip irrigation to prevent salinization, the system automatically switches control strategies based on seasonal changes and soil conditions, requiring no manual intervention. Through a continuous cycle of "data collection - strategy generation - execution feedback," it achieves dynamic balance of salinity in saline-alkali land and efficient utilization of water resources.

[0044] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0045] Figure 1 This is an isometric schematic diagram of an embodiment of the intelligent irrigation and salinity regulation integrated system for improving saline-alkali land for cotton production according to the present invention;

[0046] Figure 2 This is an embodiment of the intelligent irrigation and salinity control integrated system for improving saline-alkali land for cotton cultivation according to the present invention. Figure 1 Axonometric sectional view of section A in the middle;

[0047] Figure 3 This is a schematic diagram of the system framework of an embodiment of the intelligent irrigation and salinity regulation integrated system for improving cotton saline-alkali land according to the present invention.

[0048] The reference numerals in the accompanying drawings of the instruction manual include: 1. Irrigation pipe; 2. Branch pipe; 3. Converter ring; 4. First hole; 5. Crank-connecting rod mechanism; 6. First fixing block; 7. Water inlet; 8. Support rod; 9. Collection groove; 10. Second connecting plate; 11. First connecting plate; 12. Sealing ring; 13. Elastic sealing strip; 14. Second hole; 15. Drip irrigation area; 16. Water injection area; 17. Water outlet. Detailed Implementation

[0049] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0051] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0052] The following detailed description illustrates the specific implementation methods:

[0053] Example 1:

[0054] As attached Figure 1As shown: Existing methods for improving saline-alkali land using saline water regulation require manual sweeping of the frozen brine to the soil surface for even distribution during winter irrigation. This results in low efficiency, high labor intensity, and uneven brine distribution. Furthermore, traditional irrigation systems struggle to automatically adjust irrigation patterns based on seasonal changes and soil conditions, leading to the return of deep soil salts to the surface in spring due to evaporation, thus affecting the improvement effect. Therefore, this paper proposes an integrated intelligent irrigation and salinity control system for improving cotton saline-alkali land. This system includes several irrigation pipes 1 and a variable frequency water pump. All irrigation pipes 1 are connected to the variable frequency water pump, and several branch pipes 2 are connected to the irrigation pipes 1. Each irrigation pipe 1 is equipped with a solenoid valve, and each connection between the solenoid valve and the irrigation pipe 1 is equipped with a zone valve. The solenoid valve signal is connected to the irrigation control system. Several adjustment devices are also sleeved on the irrigation pipe 1. Each adjustment device includes several stages of support rods 8 that are sleeved end to end. Each support rod 8 has an inlet 7 near the bottom end to allow brine to enter the support rod 8. Each support rod 8 is equipped with a buoyancy deployment mechanism for driving the next stage support rod 8 to deploy vertically by injecting brine. A conversion component is provided between the irrigation pipe 1 and the last stage support rod 8 to switch the drainage hole diameter at the branch pipe 2 according to the lifting height of the support rod 8. When salt is injected and the soil freezes, a 2-3 cm thick layer of brine needs to be injected first to freeze the soil surface. To prevent excessive water flow from wasting resources and causing a large amount of brine to seep into the soil, the water flow needs to be controlled during the initial injection stage. At the same time, the water needs to be spread evenly on the soil surface. However, since the existing technology uses manual sweeping, which is inefficient and uneven, this solution uses an irrigation control system to regulate water pressure by controlling a variable frequency water pump and to control the water volume by using solenoid valves and zone valves. When the initial thin ice layer (2-3 cm) is laid, the conversion component is in a small-diameter drainage state.

[0055] Specifically, each conversion assembly includes a first fixing block 6 fixedly connected to the outer wall of any first-level support rod 8. A crank-connecting rod mechanism 5 is hinged to the first fixing block 6. A conversion ring 3 is hinged to the end of the crank-connecting rod mechanism 5 away from the first fixing block 6. The conversion ring 3 is sleeved on the branch pipe 2 and rotatably connected to the branch pipe 2. Each branch pipe 2 has a water outlet hole 17. The conversion ring 3 is divided into a water injection area 16 and a drip irrigation area 15. The water injection area 16 has only a single first hole 4. The drip irrigation area 15 has several second holes 14. A pressure compensation diaphragm is provided on the inner wall of the drip irrigation area 15. The diameter of the water outlet hole 17 is ≥ the diameter of the first hole 4 > the diameter of the second hole 14. An elastic sealing strip 13 is provided around the conversion ring 3 and the branch pipe 2. The elastic sealing strip 13 is used to seal and separate the water injection area 16 and the drip irrigation area 15. When laying the initial thin ice layer in direct contact with the soil, the rotation of the conversion ring 3 on the branch pipe 2 aligns the drip irrigation area 15 with the outlet hole 17. Since it is necessary to quickly spread the brine on the soil surface, a large water flow is required to meet the conditions. To prevent the uneven water pressure fluctuation between the small diameter of the second hole 14 and the high-pressure water flow from causing the conversion ring 3 and the branch pipe 2 to break, a pressure compensation diaphragm is used to balance the water pressure fluctuation at the second hole 14 and the outlet hole 17. Since the diameter of the second hole 14 is smaller than the diameter of the outlet hole 17, according to the Venturi principle, the fluid velocity will increase when it enters a smaller space from a larger space. Therefore, it is ensured that the brine can be sprayed out quickly from the branch pipe 2 to the second hole 14, and the brine can be delivered as far as possible to the soil in the middle of the adjacent irrigation pipe 1, so as to achieve rapid spreading of the brine on the soil surface without manual intervention.

[0056] Each branch pipe 2 is embedded with symmetrically arranged magnetic positioning plates, and each conversion ring 3 is embedded with an iron induction plate corresponding to the magnetic positioning plate. The magnetic positioning plates in the branch pipe 2 cooperate with the iron induction plates on the conversion ring 3 to ensure the accurate position of the conversion ring 3 and achieve stable switching of the drainage hole diameter.

[0057] After the initial thin ice layer freezes, it prevents brine from seeping into the soil, allowing for an increase in water injection. Specifically, each buoyancy deployment mechanism includes a float fixedly connected to the bottom of the support rod 8. As brine is continuously injected, some brine enters the interior through the inlet 7 of the support rod 8, and the buoyancy deployment mechanism begins to function. The float at the bottom of the next-level support rod 8 rises under the buoyancy of the brine. Each support rod 8 has an opening at its top, and a sealing ring 12 is fixedly connected inside each opening. When the next-level support rod 8 expands or contracts, it slides with the sealing ring 12, causing the next-level support rod 8 to expand vertically from the opening at the top of the upper-level support rod 8. The irrigation pipe 1 rises with the support rod 8, preventing the irrigation pipe 1 and branch pipe 2 from gradually freezing inside the ice layer during water injection. The frozen irrigation pipe 1 and branch pipe 2 may deform and crack due to the stress generated by the contraction of the ice layer. The sealing ring 12 ensures the sealing during the sliding connection. During the vertical unfolding of the support rod 8, the first fixing block 6, fixed to its outer wall, pulls the conversion ring 3 to rotate via the crank-connecting rod mechanism 5. When the support rod 8 is raised to a certain height, the conversion ring 3 can rotate to align the water injection area 16 with the water outlet 17. Since the diameter of the first hole 4 is larger than that of the second hole 14, the water injection volume and water pressure remain unchanged. When the brine flows out of the water injection area 16, the flow rate slows down. Without causing a huge impact on the thin ice layer, a salt water ice layer of 18-21 cm is quickly formed on the top of the thin ice layer. When the ice layer freezes, the first fixing block 6 located outside the support rod 8 and part of the crank-connecting rod mechanism 5 are frozen inside the ice layer, achieving physical self-locking of the conversion ring 3.

[0058] Because salt accumulation in saline irrigation can easily cause internal corrosion of irrigation pipe 1, branch pipe 2, and support rod 8, the inner walls of irrigation pipe 1, branch pipe 2, and support rod 8 are coated with fusion-bonded epoxy powder coating and polyethylene coating from the inside out. The fusion-bonded epoxy powder coating and polyethylene coating have corrosion resistance, ensuring that saline water can be transported stably for a long time.

[0059] When brine melts and seeps into the soil in spring, to reduce soil surface evaporation due to rising temperatures and prevent deep salts from returning to the soil surface with the evaporating water, the soil surface needs to be covered with a mulch film. Simultaneously, drip irrigation under the mulch film is required for plant irrigation. Therefore, when the brine ice layer melts and the brine seeps in, the floats inside the support rods 8 lose buoyancy, and each level of the support rods 8 retracts sequentially under its own weight. As the support rods 8 retract, the irrigation pipe 1 approaches the ground, and the crank-connecting rod mechanism 5 drives the conversion ring 3 to rotate in the opposite direction, aligning the drip irrigation area 15 with the outlet hole 17 again. At this point, after laying the mulch film, the irrigation pipe 1 can be located below the mulch film, and by using drip irrigation under the mulch film, the small-diameter drainage minimizes the water injection volume, providing water slowly in a drip irrigation manner. This method effectively solves the problem of spring salt return in existing technologies.

[0060] Example 2:

[0061] As attached Figure 1 As shown, the difference from Embodiment 1 is that the support rod 8 has several storage slots 9 at its ends, and a second fixing block is fixedly connected in each storage slot 9. A first connecting plate 11 and a second connecting plate 10 are respectively hinged to the second fixing block. An arc-shaped slide rail is opened on the outer bottom wall of the irrigation pipe 1. A first slider and a second slider are respectively hinged to the end of the first connecting plate 11 and the second connecting plate 10 away from the second fixing block. The first slider and the second slider are both located in the arc-shaped slide rail and slide in cooperation with the arc-shaped slide rail.

[0062] The curved slide rail is equipped with a damping component to reduce the impact when the first connecting plate 11 and the second connecting plate 10 are extended or retracted. The damping component includes a first spring and a second spring. The two ends of the first spring are fixedly connected between the first slider and the second slider, respectively, and the two ends of the second spring are fixedly connected to the second slider and the side wall of the curved slide rail, respectively.

[0063] The specific implementation process is as follows: During the continuous injection of brine to vertically expand the support rod 8, the second fixing block in the receiving groove 9 at the end of the support rod 8 also rises with the support rod 8. The first connecting plate 11 and the second connecting plate 10, during the rising process, disengage from the constraint of the previous stage support rod 8 and expand. The first connecting plate 11 and the second connecting plate 10 drive the first slider and the second slider to slide within the arc-shaped slide rail on the outer bottom wall of the irrigation pipe 1. This linkage design ensures that the support rod 8 provides stable support for the irrigation pipe 1 during vertical expansion, preventing displacement or deformation of the irrigation pipe 1 due to uneven force. Simultaneously, the first spring and the second spring work together to mitigate the impact when the first connecting plate 11 and the second connecting plate 10 expand, preventing damage to components due to excessive instantaneous impact force, and ensuring stable support for the irrigation pipe 1 when the support rod 8 vertically expands or contracts. Meanwhile, traditional techniques typically require the formation of a 20-25cm layer of saline ice. However, due to the presence of rain and snow in winter, and considering that secondary freezing of the support rod 8 after rain and snowfall may cause the irrigation pipe 1 and branch pipe 2 to freeze into the snow or ice layer, the irrigation pipe 1 is supported by the first connecting plate 11 and the second connecting plate 10. With the 18-21cm ice layer design set in this scheme, a height error of 2-4cm is reserved. This not only avoids the irrigation pipe 1 and branch pipe 2 from freezing into the ice layer during secondary freezing, but also allows for the collection of fresh water located above the ice layer, providing fresh water resources for rinsing saline soil after subsequent thawing.

[0064] When the brine melts and seeps into the soil in spring, the brine ice layer inside the support rod 8 melts, the float loses buoyancy, and each level of the support rod 8 retracts sequentially under its own weight. Simultaneously, the first connecting plate 11 and the second connecting plate 10, driven by the support rod 8, retract by sliding in opposite directions within the arc-shaped slide rail via the first and second sliders, and are repositioned into the receiving groove 9 at the end of the support rod 8. When the support rod 8 and its linkage structure retract rapidly under gravity, if there is a lack of buffering, the first connecting plate 11 and the second connecting plate 10 will generate a momentary impact force on the arc-shaped slide rail on the outer bottom wall of the irrigation pipe 1 via the sliders. As the main channel carrying water flow, the irrigation pipe 1 is prone to stress fatigue under this momentary impact, leading to thinning of the pipe wall, loosening of the joints, or even breakage. Furthermore, if the contraction impact causes the irrigation pipe to sway or shift, it may cause misalignment between the branch pipe outlet and the small-diameter area of ​​the conversion ring, resulting in unstable drip irrigation flow. The buffering effect of the first and second springs causes the support rod 8 to retract at a uniform speed. Combined with the precise alignment of the magnetic positioning plate and the iron induction plate, the reset error of the irrigation pipe 1 can be controlled within ±2mm, ensuring that the water flow in drip irrigation mode is stably output through the pressure compensation diaphragm.

[0065] Example 3:

[0066] As attached Figure 1 As shown, the difference from Embodiment 2 is that the irrigation control system includes a sensing unit, a data acquisition and processing module, a strategy generation module, and an execution control module, wherein:

[0067] The sensing unit is connected to the variable frequency water pump, the solenoid valve and the iron induction plate respectively. The sensing unit includes several soil sensors, flow rate sensors and displacement sensors installed on the irrigation pipe 1 and the support rod 8. The sensing unit transmits the data from the sensors through several paths to the data acquisition module.

[0068] The data acquisition module is used to receive data from the sensing unit, including the frequency of the variable frequency water pump, the opening degree of the solenoid valve, the position data of the switching ring 3, the soil salt concentration, the soil surface temperature, the soil surface humidity, the water flow rate data in the irrigation pipe 1, and the vertical unfolding height of the support rod 8. The module then uses data filtering and normalization to obtain the processed environmental dataset and equipment dataset, which are then transmitted to the strategy generation module and the execution control module, respectively.

[0069] The strategy generation module receives environmental and equipment datasets, calculates the ice formation rate by extracting soil surface temperature and the vertical unfolding height of support rod 8, and generates water injection adjustment instructions; it obtains dynamic salt concentration values ​​by extracting soil salt concentration, matches the drip irrigation rate based on the dynamic salt concentration values ​​and soil surface moisture, and transmits the water injection adjustment instructions and drip irrigation rate to the execution control module.

[0070] The strategy generation module includes an ice layer construction control unit, which calculates the ice layer thickness based on the vertical deployment height data of the support rod 8 and the soil surface temperature data, using the ice layer growth rate formula.

[0071]

[0072] V1 = K*(Hh / T)

[0073] Where V0 represents the freezing rate in the range where the ice thickness is less than 2-3 cm, K is a correction factor, T0 is the freezing point temperature, and T s The soil surface temperature is t, and the real-time water injection time is t. The freezing rate is calculated when the ice layer thickness reaches 2-3 cm. When the freezing rate is lower than the set threshold, the water injection volume adjustment command is generated and transmitted to the execution control module.

[0074] V1 represents the icing rate when the ice thickness is greater than 2-3cm, H represents the vertical deployment height data, h represents the initial height difference between the displacement sensor and the ground, and T is the current temperature. By calculating the icing rate when the ice thickness is greater than 2-3cm, when the icing rate is lower than a set threshold, a water injection adjustment command to increase the water injection volume is generated and transmitted to the execution control module; when the ice thickness Hh is between 20cm and 25cm, a water injection adjustment command to shut off the water injection volume is generated and transmitted to the execution control module.

[0075] The strategy generation module also includes a drip irrigation control unit, which receives soil salinity C. s A gradient dilution model is used:

[0076] Q = Q0 * (C s / C max ) n

[0077] Where Q0 is the baseline drip irrigation volume, and C max Where C is the upper limit of salt concentration, n is the dilution gradient coefficient, and C is the upper limit of salt concentration. s ≥C max At that time, the target drip irrigation volume is calculated through the gradient dilution model, and the drip irrigation rate is generated and sent to the execution control module. The execution control module generates a speed adjustment command and transmits it to the variable frequency water pump to adjust the water flow.

[0078] The execution control module is used to receive water injection volume adjustment commands and drip irrigation rates. By extracting and comparing real-time variable frequency pump frequency, solenoid valve opening, switch ring 3 position data and water flow rate data, it controls and adjusts the variable frequency pump frequency and solenoid valve opening according to the water injection volume adjustment commands and drip irrigation rates.

[0079] The specific implementation process is as follows: After the irrigation control system is started, the strategy generation module determines that the ambient temperature is below freezing based on the soil surface temperature, and begins to inject water through drip irrigation zone 15, with an initial water volume of 5m³. 3 The water flow rate is 2.5 m / s, and the coverage radius reaches 8 m. After the ice layer thickness reaches 2-3 cm based on the calculated freezing rate, the support rod 8 expands due to buoyancy, lifting the irrigation pipe 1. The switching ring 3 switches to the water injection zone 16. According to the displacement sensor, the support rod 8 begins to expand vertically. At this time, the zone valve is switched via the solenoid valve, and the water injection volume increases to 20 m³ / h. 3 / h, accelerate the formation of an 18-21cm salt ice layer. The strategy generation module switches to calculating the ice growth rate under the current water injection volume to estimate the required water injection time. When the water injection time is reached, it calculates whether the current ice layer thickness Hh has reached the preset ice layer thickness and then determines whether to continue water injection.

[0080] When the soil surface temperature rises to 5℃, the ice layer inside the support rod 8 melts and shrinks back to its original position. The conversion ring 3 resets to the drip irrigation area 15. The strategy generation module generates a drip irrigation rate command based on the soil salt concentration. The variable frequency water pump adjusts its speed to 1800 rpm and starts drip irrigation under the film to suppress salt back-seepage.

[0081] To verify the innovativeness of this scheme, two adjacent saline-alkali land plots (each 1000㎡, with an initial salt content of 8-10g / kg) were selected, and the following methods were used respectively:

[0082] Control group: Traditional manual sweeping of saline solution + fixed drip irrigation system;

[0083] Experimental group: The integrated intelligent irrigation and salinity control system of this scheme.

[0084] Experimental period: 2 full years (including the winter freezing period and the spring salt return period).

[0085] Monitoring indicators:

[0086] Winter work efficiency (labor input time, time required to complete the same area);

[0087] Ice layer thickness uniformity (one measurement point is taken every 10 square meters, for a total of 100 points);

[0088] Changes in soil salinity in the topsoil layer (0–20 cm) during spring;

[0089] Assume the improved cotton yield (statistics for each year).

[0090] Experimental results:

[0091]

[0092] Conclusion: The comparative experimental data show that, compared with the traditional method of manually sweeping salt and using fixed drip irrigation to improve saline-alkali land, this integrated intelligent irrigation and salt regulation system demonstrates significant advantages in multiple dimensions, including labor input, ice layer uniformity, salt control, and crop yield increase. While saving manpower, it reduces surface salt content by more than 50% by improving ice layer uniformity by 65%, and increases cotton yield by 10%. This fully verifies its innovative value in the automation, precision, and efficiency of saline-alkali land improvement, providing a more scientific and reliable solution for saline-alkali land management.

[0093] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An integrated intelligent irrigation and salinity control system for improving saline-alkali land for cotton cultivation, comprising several irrigation pipes (1) and a variable frequency water pump, wherein each irrigation pipe (1) is connected to the variable frequency water pump, and several branch pipes (2) are connected to each irrigation pipe (1), each irrigation pipe (1) is equipped with a solenoid valve, and a zone valve is provided at the connection between the solenoid valve and the irrigation pipe (1), characterized in that, The solenoid valve signal is connected to the irrigation control system; the irrigation pipe (1) is also fitted with several adjustment devices, each of which includes several levels of support rods (8) that are connected end to end. The support rods (8) are all opened near the bottom end to allow brine to enter the support rods (8). The support rods (8) are all equipped with a buoyancy deployment mechanism for driving the next level support rod (8) to unfold vertically by injecting brine. The irrigation pipe (1) and the last level support rod (8) are all equipped with a conversion component for switching the drainage hole diameter at the branch pipe (2) according to the lifting height of the support rod (8). Each conversion component includes a first fixed block (6) fixedly connected to the outer wall of any first-level support rod (8). A crank-connecting rod mechanism (5) is hinged on the first fixed block (6). A conversion ring (3) is hinged to the end of the crank-connecting rod mechanism (5) away from the first fixed block (6). The conversion ring (3) is sleeved on the branch pipe (2) and rotatably connected to the branch pipe (2). A water outlet hole (17) is opened on the branch pipe (2). The conversion ring (3) is divided into a water injection area (16) and a drip irrigation area (15). The water injection area (16) has only a single first hole (4). The drip irrigation area (15) has several second holes (14). A pressure compensation diaphragm is provided on the inner wall of the drip irrigation area (15). The diameter of the water outlet hole (17) is ≥ the diameter of the first hole (4) > the diameter of the second hole (14).

2. The integrated intelligent irrigation and salinity control system for improving saline-alkali land for cotton cultivation according to claim 1, characterized in that, An elastic sealing strip (13) is provided around both the conversion ring (3) and the branch pipe (2). The elastic sealing strip (13) is used to seal and separate the water injection area (16) and the drip irrigation area (15).

3. The integrated intelligent irrigation and salinity control system for improving saline-alkali land for cotton cultivation according to claim 2, characterized in that, Each buoyancy deployment mechanism includes a float fixedly connected to the bottom of the next-level support rod (8). Each support rod (8) has an opening at its top, and a sealing ring (12) is fixedly connected inside the opening. The next-level support rod (8) is slidably connected to the sealing ring (12) when it is deployed or retracted.

4. The integrated intelligent irrigation and salinity control system for improving saline-alkali land for cotton cultivation according to claim 3, characterized in that, Several storage slots (9) are opened at the ends of the support rods (8). A second fixing block is fixedly connected in each storage slot (9). A first connecting plate (11) and a second connecting plate (10) are respectively hinged on the second fixing block. An arc-shaped slide rail is opened on the bottom wall of the irrigation pipe (1). A first slider and a second slider are respectively hinged at the ends of the first connecting plate (11) and the second connecting plate (10) away from the second fixing block. The first slider and the second slider are both located in the arc-shaped slide rail and slide in cooperation with the arc-shaped slide rail.

5. The integrated intelligent irrigation and salinity control system for improving saline-alkali land for cotton cultivation according to claim 4, characterized in that, The curved slide rail is equipped with a damping component to reduce the impact when the first connecting plate (11) and the second connecting plate (10) expand or contract. The damping component includes a first spring and a second spring. The two ends of the first spring are fixedly connected between the first slider and the second slider, respectively, and the two ends of the second spring are fixedly connected to the second slider and the side wall of the curved slide rail, respectively.

6. The integrated intelligent irrigation and salinity control system for improving saline-alkali land for cotton cultivation according to claim 5, characterized in that, The inner walls of the irrigation pipe (1), branch pipe (2) and support rod (8) are coated with fusion-bonded epoxy powder coating and polyethylene coating from the inside out.

7. The integrated intelligent irrigation and salinity control system for improving saline-alkali land for cotton cultivation according to claim 6, characterized in that, Each branch pipe (2) is embedded with symmetrically arranged magnetic positioning plates, and each conversion ring (3) is embedded with an iron induction plate corresponding to the magnetic positioning plate.

8. The integrated intelligent irrigation and salinity control system for improving saline-alkali land for cotton cultivation according to claim 7, characterized in that, The irrigation control system includes a sensing unit, a data acquisition and processing module, a strategy generation module, and an execution control module, wherein: The sensing unit is connected to the variable frequency water pump, the solenoid valve and the iron induction plate respectively. The sensing unit includes several soil sensors, flow rate sensors and displacement sensors installed on the irrigation pipe (1) and the support rod (8). The sensing unit transmits the sensors through several paths to the data acquisition module. The data acquisition module is used to receive data from the sensor unit, including the frequency of the variable frequency water pump, the opening degree of the solenoid valve, the position data of the switching ring (3), the soil salt concentration, the soil surface temperature, the soil surface humidity, the water flow rate data in the irrigation pipe (1), and the vertical unfolding height of the support rod (8). The module uses data filtering and normalization to obtain the processed environmental dataset and equipment dataset, and transmits them to the strategy generation module and the execution control module, respectively. The strategy generation module is used to receive environmental datasets and equipment datasets, calculate the ice formation rate by extracting soil surface temperature and vertical unfolding height of support rod (8), and generate water injection adjustment instructions; obtain dynamic salt concentration values ​​by extracting soil salt concentration, and match drip irrigation rate according to dynamic salt concentration values ​​and soil surface humidity; transmit water injection adjustment instructions and drip irrigation rate to execution control module. The execution control module is used to receive water injection volume adjustment instructions and drip irrigation rate. By extracting real-time variable frequency pump frequency, solenoid valve opening, conversion ring (3) position data and water flow rate data for comparison, the variable frequency pump frequency and solenoid valve opening are controlled and adjusted according to the water injection volume adjustment instructions and drip irrigation rate.

9. The integrated intelligent irrigation and salinity control system for improving saline-alkali land for cotton cultivation according to claim 8, characterized in that, The strategy generation module includes an ice layer construction control unit, which calculates the ice layer thickness using the ice layer growth rate formula based on the vertical unfolding height data of the support rod (8) and the soil surface temperature data. V1 = K*(Hh / T) Where V0 represents the freezing rate in the range where the ice thickness is less than 2-3 cm, K is a correction factor, T0 is the freezing point temperature, and T s The soil surface temperature is t, and the real-time water injection time is t. The freezing rate is calculated when the ice layer thickness reaches 2-3 cm. When the freezing rate is lower than the set threshold, the water injection volume adjustment command is generated and transmitted to the execution control module. V1 represents the icing rate when the ice thickness is greater than 2-3cm, H represents the vertical deployment height data, h represents the initial height difference between the displacement sensor and the ground, and T is the current temperature. By calculating the icing rate when the ice thickness is greater than 2-3cm, when the icing rate is lower than the set threshold, a water injection adjustment command to increase the water injection volume is generated and transmitted to the execution control module; when the ice thickness Hh is between 20cm and 25cm, a water injection adjustment command to shut off the water injection volume is generated and transmitted to the execution control module.

10. The integrated intelligent irrigation and salinity control system for improving saline-alkali land for cotton cultivation according to claim 9, characterized in that, The strategy generation module also includes a drip irrigation control unit, which receives soil salt concentration C. s A gradient dilution model is used: Q=Q0*(C s / C max ) n Where Q0 is the baseline drip irrigation volume, and C max Where C is the upper limit of salt concentration, n is the dilution gradient coefficient, and C is the upper limit of salt concentration. s ≥C max At that time, the target drip irrigation volume is calculated through the gradient dilution model, and the drip irrigation rate is generated and sent to the execution control module. The execution control module generates a speed adjustment command and transmits it to the variable frequency water pump to adjust the water flow.

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