Optimized regulation and control technology for water, fertilizer and salt in soda saline-alkali soil

Abstract

The invention relates to the technical field of saline-alkali soil improvement and efficient utilization of agricultural resources, in particular to a soda saline-alkali soil water, fertilizer and salt optimization regulation and control technology. Through linkage regulation and control of water, fertilizer and salt, the pH value of soil can be reduced by 0.8-1.5 units, the EC value is reduced by 40%-60%, the nutrient utilization rate is increased by 25% or above, and the contradiction of'fertilizer loss due to salt change and salt accumulation during fertilization 'in the traditional technology is solved; parameters are dynamically adjusted based on real-time monitoring data, compared with empirical regulation, irrigation water is reduced by 30%, the chemical fertilizer dosage is reduced by 20%, and the improvement cost is reduced; the soil conditioner can adapt to different crops such as rice and corn, and is suitable for moderately severe soda saline-alkali soil with the EC value of 4-8 mS / cm, and the yield of the improved crops is increased by 30%-50%.

Description

Technical Field

[0001] This invention relates to the field of saline-alkali land improvement and efficient utilization of agricultural resources, and in particular to a water, fertilizer and salt optimization and regulation technology for soda saline-alkali land. Background Technology

[0002] Soda-saline-alkali land, with Na₂CO₃ and NaHCO₃ as its main saline components, is characterized by high pH (typically 8.5-10.5), high exchangeable sodium ion content, compacted soil structure, and lack of organic matter. This leads to hindered water and fertilizer absorption by crop roots, resulting in low nutrient utilization efficiency and severely restricting agricultural production. Existing improvement technologies mainly focus on single-stage regulation, which has significant limitations.

[0003] Soil improvement and water and fertilizer regulation are disconnected: Traditional techniques often rely on soil conditioners with fixed formulas to reduce salinity and improve soil. However, the application of conditioners lacks coordination with water and fertilizer programs, often resulting in the contradiction of nutrient loss due to salt leaching or the exacerbation of salt accumulation by fertilization.

[0004] Insufficient precision in regulation: Existing technologies mostly adopt experience-based irrigation and fertilization models, without considering the dynamic changes in soil salinity, making it difficult to match the water and fertilizer requirements and salt tolerance thresholds of crops at different growth stages.

[0005] Lack of closed-loop feedback mechanism: Most technologies only guide regulation through soil physicochemical indicators and do not make real-time corrections based on crop growth, resulting in delayed regulation effects and inability to respond to problems such as salinity rebound in a timely manner.

[0006] Therefore, developing a precision technology that enables the coordinated operation of soil improvement, water and fertilizer supply, and salinity regulation is of great significance for the efficient utilization of soda saline-alkali land. Summary of the Invention

[0007] The purpose of this invention is to provide a technology for optimizing and regulating water, fertilizer, and salt content in soda-alkali land.

[0008] To achieve the above objectives, the present invention provides the following solution:

[0009] This invention provides a method for optimizing and regulating water, fertilizer, and salt content in soda-saline-alkali land, comprising a real-time monitoring module for multiple soil parameters, a customized compound soil conditioner application system, a dynamic water and fertilizer irrigation regulation system, and a closed-loop feedback correction module. The specific steps are as follows:

[0010] Soil baseline data acquisition: The initial pH value, EC value, volumetric water content, organic matter content and exchangeable sodium ion content of the 0-40cm topsoil layer of the target soda saline-alkali land are obtained through the real-time monitoring module for multiple soil parameters.

[0011] Preparation and application of customized soil conditioner: Based on the baseline data collected in step 1, an organic-inorganic-biological composite soil conditioner is prepared using the customized composite soil conditioner application system, and then evenly spread on the soil surface and rotary tilled to a depth of 20-30 cm. The composite soil conditioner consists of the following components in parts by weight: 30-45 parts humic acid, 80-120 parts phosphogypsum, 150-200 parts sucralose residue, 100-150 parts well-rotted organic fertilizer, 50-70 parts zeolite powder, 5-10 parts Bacillus subtilis, 3-8 parts 001×7 cation exchange resin, and 1-3 parts zinc sulfate heptahydrate.

[0012] Implementation of dynamic water and fertilizer irrigation scheme: The dynamic water and fertilizer irrigation control system dynamically adjusts the irrigation amount and water-fertilizer ratio according to the crop growth stage based on the soil EC value and moisture content data transmitted in real time by the monitoring module: During the seedling stage, maintain soil EC ≤ 3.0 mS / cm and moisture content at 60-70% of field capacity, and apply a water-fertilizer mixture with a nitrogen, phosphorus and potassium ratio of 2:1:1; During the jointing stage, maintain soil EC ≤ 2.5 mS / cm and moisture content at 70-80% of field capacity, and apply a water-fertilizer mixture with a nitrogen, phosphorus and potassium ratio of 1:1:2.

[0013] Closed-loop feedback correction: The closed-loop feedback correction module collects crop NDVI vegetation index and root fresh weight data. When the NDVI value is lower than 85% of the threshold for the same period or the root fresh weight decreases by 15% compared with the standard value, parameter correction is triggered, adjusting the amount of amendment or the water-fertilizer ratio.

[0014] Preferably, the real-time soil multi-parameter monitoring module includes a distributed sensor array with a sensor spacing of 5-8m, which can simultaneously monitor pH value (measurement range 7.5-11.0), EC value (measurement range 0-10mS / cm), volumetric water content (measurement range 0-50%), and available nitrogen, phosphorus, and potassium content, with a data transmission frequency of once every 2 hours.

[0015] Preferably, the preparation method of the composite amendment includes: pulverizing humic acid, phosphogypsum, sucralose residue, and decomposed organic fertilizer to a particle size ≤2mm, mixing and stirring with zeolite powder for 15-20min; sequentially adding Bacillus subtilis, cation exchange resin, and zinc sulfate heptahydrate, and continuing to stir for 10-15min until uniform, wherein the cation exchange resin needs to be pretreated with 10% sodium chloride solution for 24h.

[0016] Preferably, the dynamic water and fertilizer irrigation control system adopts a combination of drip irrigation and underground pipe salt drainage. The underground pipes are buried at a depth of 40-50cm and spaced 3-5m apart. The irrigation water is used after reverse osmosis treatment, and the water and fertilizer mixture is prepared online through a Venturi fertilizer applicator.

[0017] Preferably, the threshold setting of the closed-loop feedback correction module is based on the target crop type calibration: the standard threshold for NDVI during the rice seedling stage is 0.3-0.4, and the standard threshold for NDVI during the corn jointing stage is 0.5-0.6. The regulation is completed within 24 hours after the parameter correction.

[0018] Preferably, the application rate of the compound fertilizer is dynamically adjusted according to the initial EC value: when the EC value is 4-6 mS / cm, the application rate is 150-200 kg / mu; when the EC value is ≥6 mS / cm, the application rate is 200-250 kg / mu, and it is applied twice, once at the basal fertilizer stage (70%) and once at the jointing stage (30%).

[0019] The present invention discloses the following technical effects:

[0020] Significant synergistic regulation effect: Through the coordinated regulation of water, fertilizer and salt, the soil pH value can be reduced by 0.8-1.5 units, the EC value can be reduced by 40%-60%, and the nutrient utilization rate can be increased by more than 25%, which solves the contradiction of "salt loss due to salt conversion and salt accumulation due to fertilization" in traditional technology.

[0021] Precision and intelligence: Based on real-time monitoring data, parameters are dynamically adjusted, reducing irrigation water consumption by 30% and fertilizer usage by 20% compared to experience-based regulation, thus lowering improvement costs.

[0022] Wide applicability: It can be adapted to different crops such as rice and corn, and is suitable for moderate to severe soda saline-alkali land with EC values ​​of 4-8 mS / cm. After improvement, crop yield can be increased by 30%-50%. Detailed Implementation

[0023] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0024] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0025] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0026] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be obvious to those skilled in the art. This specification and embodiments are merely exemplary.

[0027] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0028] Example 1 Method

[0029] It includes a real-time monitoring module for multiple soil parameters, a customized compound soil conditioner application system, a dynamic water and fertilizer irrigation control system, and a closed-loop feedback correction module. The specific steps are as follows:

[0030] Soil baseline data acquisition: The initial pH value, EC value, volumetric water content, organic matter content and exchangeable sodium ion content of the 0-40cm topsoil layer of the target soda saline-alkali land were obtained through the real-time monitoring module for multiple soil parameters.

[0031] Preparation and application of customized soil conditioner: Based on the baseline data collected in step 1, an organic-inorganic-biological composite soil conditioner is prepared using the customized composite soil conditioner application system, and then evenly spread on the soil surface and rotary tilled to a depth of 20-30 cm. The composite soil conditioner consists of the following components in parts by weight: 30-45 parts humic acid, 80-120 parts phosphogypsum, 150-200 parts sucralose residue, 100-150 parts well-rotted organic fertilizer, 50-70 parts zeolite powder, 5-10 parts Bacillus subtilis, 3-8 parts 001×7 cation exchange resin, and 1-3 parts zinc sulfate heptahydrate.

[0032] Implementation of dynamic water and fertilizer irrigation scheme: The dynamic water and fertilizer irrigation control system dynamically adjusts the irrigation amount and water-fertilizer ratio according to the crop growth stage based on the soil EC value and moisture content data transmitted in real time by the monitoring module: During the seedling stage, maintain soil EC ≤ 3.0 mS / cm and moisture content at 60-70% of field capacity, and apply a water-fertilizer mixture with a nitrogen, phosphorus and potassium ratio of 2:1:1; During the jointing stage, maintain soil EC ≤ 2.5 mS / cm and moisture content at 70-80% of field capacity, and apply a water-fertilizer mixture with a nitrogen, phosphorus and potassium ratio of 1:1:2.

[0033] Closed-loop feedback correction: The closed-loop feedback correction module collects crop NDVI vegetation index and root fresh weight data. When the NDVI value is lower than 85% of the threshold for the same period or the root fresh weight decreases by 15% compared with the standard value, parameter correction is triggered to adjust the amount of amendment or the water-fertilizer ratio.

[0034] The real-time soil multi-parameter monitoring module includes a distributed sensor array with a sensor spacing of 5-8m. It can simultaneously monitor pH value (measurement range 7.5-11.0), EC value (measurement range 0-10mS / cm), volumetric water content (measurement range 0-50%), and available nitrogen, phosphorus, and potassium content. The data transmission frequency is once every 2 hours.

[0035] The preparation method of the composite amendment includes: pulverizing humic acid, phosphogypsum, sucralose residue, and decomposed organic fertilizer to a particle size ≤2mm, mixing and stirring with zeolite powder for 15-20min; adding Bacillus subtilis, cation exchange resin and zinc sulfate heptahydrate in sequence, and continuing to stir for 10-15min until uniform, wherein the cation exchange resin needs to be pretreated with 10% sodium chloride solution for 24h.

[0036] The dynamic water and fertilizer irrigation control system adopts a combination of drip irrigation and underground pipe salt drainage. The underground pipes are buried at a depth of 40-50cm and spaced 3-5m apart. The irrigation water is treated by reverse osmosis before use, and the water and fertilizer mixture is prepared online through a Venturi fertilizer applicator.

[0037] The threshold setting of the closed-loop feedback correction module is based on the target crop type calibration: the standard threshold for NDVI during the rice seedling stage is 0.3-0.4, and the standard threshold for NDVI during the corn jointing stage is 0.5-0.6. The control is completed within 24 hours after the parameter correction.

[0038] The application rate of compound fertilizer is dynamically adjusted according to the initial EC value: when the EC value is 4-6 mS / cm, the application rate is 150-200 kg / mu; when the EC value is ≥6 mS / cm, the application rate is 200-250 kg / mu, and it is applied twice, once at the basal fertilizer stage (accounting for 70%) and once at the jointing stage (accounting for 30%).

[0039] Example 2: Rice paddy regulation

[0040] The adjustment is performed according to the method in Example 1, as follows:

[0041] Soil baseline data: initial pH = 9.8, EC = 5.2 mS / cm, organic matter content 1.2%, exchangeable sodium ion content 6.8 cmol / kg.

[0042] Preparation of compound fertilizer: It is prepared by mixing 40 parts humic acid, 100 parts phosphogypsum, 180 parts sucralose residue, 120 parts well-rotted cow manure, 60 parts zeolite powder, 8 parts Bacillus subtilis, 5 parts cation exchange resin, and 2 parts zinc sulfate heptahydrate. The application rate is 200 kg / mu, with 140 kg / mu applied during the basal fertilizer stage and 60 kg / mu applied as top dressing during the jointing stage.

[0043] Dynamic water and fertilizer regulation:

[0044] Seedling stage (5-6 leaf stage): Irrigation volume 30m³ 3 / mu / time, 5-day interval, water-fertilizer ratio N:P2O5:K2O=2:1:1, fertilizer application rate 15kg / mu;

[0045] Jointing stage: Irrigation volume 40m 3 / mu·time, 3 days apart, water and fertilizer ratio N:P2O5:K2O=1:1:2, fertilizer application rate 20kg / mu;

[0046] Feedback and correction: During the tillering stage, NDVI = 0.32 (standard threshold 0.3-0.4) and root fresh weight 8.2g / plant (standard value 7.5-9.0g / plant) were observed, requiring no correction; during the booting stage, EC rose to 2.8mS / cm, triggering an irrigation increment of 10%, maintaining EC ≤ 2.5mS / cm.

[0047] Results: At harvest, the soil pH was 8.6, EC was 2.1 mS / cm, and the rice yield was 580 kg / mu, an increase of 38% compared with traditional improvement techniques.

[0048] Example 3: Cornfield Regulation

[0049] The adjustment is performed according to the method in Example 1, as follows:

[0050] Soil baseline data: initial pH = 9.2, EC = 4.5 mS / cm, organic matter content 1.0%.

[0051] Preparation of compound fertilizer: It is prepared by using 40 parts humic acid, 100 parts phosphogypsum, 180 parts sucralose residue, 120 parts well-rotted cow manure, 60 parts zeolite powder, 8 parts Bacillus subtilis, 5 parts cation exchange resin, and 2 parts zinc sulfate heptahydrate. The application rate is 180 kg / mu, divided into 126 kg / mu at the base fertilizer stage and 54 kg / mu at the jointing stage.

[0052] Dynamic water and fertilizer regulation: Irrigation volume during the seedling stage is 25m³. 3 / mu / time, water-fertilizer ratio 2:1:1; irrigation amount at the jointing stage 35m³ 3 / acre / time, water-fertilizer ratio 1:1:2.

[0053] Results: At harvest, the soil pH was 8.3, EC was 1.8 mS / cm, and the corn yield was 620 kg / mu, an increase of 42% compared with traditional technology.

[0054] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for optimizing and regulating water, fertilizer, and salt content in soda-saline-alkali land, characterized in that, It includes a real-time monitoring module for multiple soil parameters, a customized compound soil conditioner application system, a dynamic water and fertilizer irrigation control system, and a closed-loop feedback correction module. The specific steps are as follows: Soil baseline data acquisition: The initial pH value, EC value, volumetric water content, organic matter content and exchangeable sodium ion content of the 0-40cm topsoil layer of the target soda saline-alkali land are obtained through the real-time monitoring module for multiple soil parameters. Preparation and application of customized soil conditioner: Based on the baseline data collected in step 1, an organic-inorganic-biological composite soil conditioner is prepared using the customized composite soil conditioner application system, and then evenly spread on the soil surface and rotary tilled to a depth of 20-30 cm. The composite soil conditioner consists of the following components in parts by weight: 30-45 parts humic acid, 80-120 parts phosphogypsum, 150-200 parts sucralose residue, 100-150 parts well-rotted organic fertilizer, 50-70 parts zeolite powder, 5-10 parts Bacillus subtilis, 3-8 parts 001×7 cation exchange resin, and 1-3 parts zinc sulfate heptahydrate. Implementation of dynamic water and fertilizer irrigation scheme: The dynamic water and fertilizer irrigation control system dynamically adjusts the irrigation amount and water-fertilizer ratio according to the crop growth stage based on the soil EC value and moisture content data transmitted in real time by the monitoring module: During the seedling stage, maintain soil EC ≤ 3.0 mS / cm and moisture content at 60-70% of field capacity, and apply a water-fertilizer mixture with a nitrogen, phosphorus and potassium ratio of 2:1:1; During the jointing stage, maintain soil EC ≤ 2.5 mS / cm and moisture content at 70-80% of field capacity, and apply a water-fertilizer mixture with a nitrogen, phosphorus and potassium ratio of 1:1:

2. Closed-loop feedback correction: The closed-loop feedback correction module collects crop NDVI vegetation index and root fresh weight data. When the NDVI value is lower than 85% of the threshold for the same period or the root fresh weight decreases by 15% compared with the standard value, parameter correction is triggered to adjust the amount of amendment or the water-fertilizer ratio.

2. The method for optimizing and regulating water, fertilizer, and salt content in soda-saline-alkali land according to claim 1, characterized in that, The real-time soil multi-parameter monitoring module includes a distributed sensor array with a sensor spacing of 5-8m. It can simultaneously monitor pH value, EC value, volumetric water content, and available nitrogen, phosphorus, and potassium content, with a data transmission frequency of once every 2 hours.

3. The method for optimizing and regulating water, fertilizer, and salt content in soda-saline-alkali land according to claim 1, characterized in that, The preparation method of the composite amendment includes: pulverizing humic acid, phosphogypsum, sucralose residue, and decomposed organic fertilizer to a particle size ≤2mm, mixing and stirring with zeolite powder for 15-20min; adding Bacillus subtilis, cation exchange resin, and zinc sulfate heptahydrate in sequence, and continuing to stir for 10-15min until uniform, wherein the cation exchange resin needs to be pretreated with 10% sodium chloride solution for 24h.

4. The method for optimizing and regulating water, fertilizer, and salt content in soda-saline-alkali land according to claim 1, characterized in that, The dynamic water and fertilizer irrigation control system adopts a combination of drip irrigation and underground pipe salt drainage. The underground pipes are buried at a depth of 40-50cm and spaced 3-5m apart. The irrigation water is treated by reverse osmosis before use, and the water and fertilizer mixture is prepared online through a Venturi fertilizer applicator.

5. The method for optimizing and regulating water, fertilizer, and salt content in soda-saline-alkali land according to claim 1, characterized in that, The threshold setting of the closed-loop feedback correction module is based on the target crop type calibration: the standard threshold for NDVI during the rice seedling stage is 0.3-0.4, and the standard threshold for NDVI during the corn jointing stage is 0.5-0.

6. The control is completed within 24 hours after the parameter correction.

6. The method for optimizing and regulating water, fertilizer, and salt content in soda-saline-alkali land according to claim 1, characterized in that, The application rate of the compound amendment is dynamically adjusted according to the initial EC value: when the EC value is 4-6 mS / cm, the application rate is 150-200 kg / mu; when the EC value is ≥6 mS / cm, the application rate is 200-250 kg / mu.