Partitioned comprehensive treatment method for saline-alkali soil

Abstract

The invention discloses a partitioned comprehensive treatment method for saline-alkali soil. The method comprises the following steps: treating the saline-alkali soil to be treated through a grid sampling method and a Kriging interpolation method to generate a soil salt content planar diagram of the saline-alkali soil to be treated; performing management zoning on the to-be-treated saline-alkali soil based on the irrigation type, obtaining a management zoning map of the to-be-treated saline-alkali soil, and obtaining a soil salt content grade map in the management zoning of the to-be-treated saline-alkali soil; improving the leaching irrigation quota model in combination with the wetting ratio to obtain a variable irrigation prescription map of the to-be-treated saline-alkali soil; and carrying out zoned comprehensive treatment on the saline-alkali soil. According to the method, accurate improvement of the saline-alkali soil is achieved through grading and zoning variable treatment, the treatment problem of a flower-arrangement-shaped saline-alkali distribution farmland is solved, and the resource utilization efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of farmland irrigation, and in particular to a method for comprehensive management of saline-alkali land by zoning. Background Art

[0002] Salinization leads to soil structure destruction, nutrient imbalance, and reduced microbial activity, severely restricting crop growth and threatening food security and ecological balance. Saline-alkali land is widely distributed in arid, semi-arid regions and coastal areas around the world. However, as a potential reserve land resource, effective saline-alkali land management can activate "potential arable land" and improve land productivity, which is of great significance to alleviating the contradiction between population and arable land resource shortages. In recent years, due to the continuous decline in groundwater levels, inland saline-alkali land has mostly been arranged in a "flower arrangement" pattern, manifested in large spatial variability in soil salinity within farmland and the coexistence of saline-alkali plots of varying degrees.

[0003] When conducting saline-alkali land treatment, commonly used methods mainly include physical methods, chemical methods, biological methods, hydraulic methods, or a combination of multiple methods. Judging from the application of the above existing technologies, the selection of these methods is based on the results of a single salinity assessment within the farmland. In view of the coexistence of saline-alkali plots of varying degrees within farmland, if a unified saline-alkali land treatment method is still adopted, local high-salinity and alkaline plots may not be well treated due to the low treatment standards adopted, or the treatment costs may increase due to the high treatment standards adopted. In particular, with the continuous expansion of the scale of high-standard farmland construction, the area of flat, concentrated and contiguous cultivated land has continued to increase, further highlighting the severity of this problem and the urgency of its solution. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a method for comprehensive management of saline-alkali land by zoning.

[0005] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is: A method for comprehensive management of saline-alkali land by zoning, comprising the following steps: The saline-alkali land to be treated is processed by grid sampling method and Kriging interpolation method to generate a surface map of soil salinity of the saline-alkali land to be treated; The saline-alkali land to be treated is divided into management zones based on the irrigation type, and a management zone map of the saline-alkali land to be treated is obtained. The soil salinity level map within the management zone of the saline-alkali land to be treated is obtained based on the soil salinity surface map and the management zone map; The leaching irrigation quota model is improved by combining the wetting ratio, and the variable irrigation prescription map of the saline-alkali land to be treated is obtained based on the improved leaching irrigation quota model and the soil salinity grade map within the saline-alkali land management zone to be treated; Based on the soil salinity grade map within the management zone of the saline-alkali land to be treated, pre-sowing treatment is carried out on the saline-alkali land to be treated, and based on the variable irrigation prescription map of the saline-alkali land to be treated, post-sowing treatment is carried out on the saline-alkali land to carry out comprehensive zoning management of the saline-alkali land.

[0006] Furthermore, the saline-alkali land to be treated is processed by the grid sampling method and the Kriging interpolation method to generate a surface map of the soil salinity of the saline-alkali land to be treated. The specific process is: the saline-alkali land to be treated is divided into grids, and the number of grids after division should be greater than or equal to 100. Then, soil samples are collected at the center of the grid, and one soil sample is collected for every 120° sector on a circle with a radius of 1 / 4 of the grid side length and the grid center as the circle point. The sampling depth is 20 cm. The four samples in the grid are made into a mixed sample and the soil salinity of the mixed sample is measured to obtain the soil salinity of the grid. Based on the soil salinity of the grid, the Kriging interpolation method is used to generate a surface map of the soil salinity of the saline-alkali land to be treated.

[0007] Further, irrigation types include center pivot irrigation, lateral sprinkler irrigation, and drip irrigation.

[0008] Furthermore, the saline-alkali land to be treated is divided into management zones based on the irrigation type, and a management zone map of the saline-alkali land to be treated is obtained, specifically: When the irrigation type is circular sprinkler irrigation, the saline-alkali land to be treated is divided into multiple sector-shaped management areas with the same irrigation angle to obtain the management zoning map of the saline-alkali land to be treated. The calculation formula for the irrigation angle is:

[0009] in: is the irrigation angle, is the spraying radius of the largest nozzle of the circular sprinkler, The distance between the farthest nozzle and the center support axis in a circular sprinkler; When the irrigation type is translatory irrigation, the saline-alkali land to be treated is divided into multiple rectangular management areas with the same irrigation width. The irrigation width is set to twice the nozzle range of the translatory irrigation machine to obtain the management zoning map of the saline-alkali land to be treated. When the irrigation type is drip irrigation, determine whether the plots with different salinization degrees in the saline-alkali land to be treated are concentrated; if so, the saline-alkali land to be treated is managed and zoned based on the control area of a single branch pipe; otherwise, the saline-alkali land to be treated is managed and zoned based on the control area of a single capillary pipe, so as to obtain the management zoning map of the saline-alkali land to be treated.

[0010] Furthermore, a soil salt content grade map within the management zone of the saline-alkali land to be treated is obtained based on the soil salt content surface map and management zone map of the saline-alkali land to be treated. The specific process is: superimpose the soil salt content surface map of the saline-alkali land to be treated and the management zone map, calculate the average soil salt content in each management area respectively, and determine the soil salt content grade in the management area according to the size of the average value, determine all management areas with the same soil salt content grade as a type of management area, and divide the entire saline-alkali land to be treated into three types of soil salt content grades: light, moderate and heavy, to obtain a soil salt content grade map within the management zone of the saline-alkali land to be treated.

[0011] Furthermore, the improved irrigation quota model is expressed as:

[0012] in: To manage the irrigation quota within the zone, is the wetting ratio, the sprinkler irrigation technology takes a value of 1, and the drip irrigation technology takes a value of 0.75. is the planned wet layer depth, To determine the water holding capacity of saline-alkali land to be managed, is the measured soil moisture content in each management zone, To plan the depth of the elution layer, is the soil density of the planned leaching layer, is the percentage of the salt content of the planned leaching layer to the dry soil weight, The percentage of the allowable salt content of the planned leaching layer after leaching to the dry soil weight. is the salt removal coefficient, is the crop evaporation and transpiration water consumption during the irrigation period, It is the effective precipitation available during the irrigation period.

[0013] Furthermore, based on the soil salinity grade map within the management zone of the saline-alkali land to be treated, the saline-alkali land to be treated is treated before sowing. Specifically, based on the soil salinity grade map within the management zone of the saline-alkali land to be treated, set doses of organic fertilizer, desulfurization gypsum or microbial agent are applied to the saline-alkali land to be treated according to applicable conditions, and the saline-alkali land to be treated is turned over and rotary tilled to carry out pre-sowing treatment of the saline-alkali land to be treated.

[0014] The present invention has the following beneficial effects: The present invention processes the saline-alkali land to be treated by a grid sampling method and a Kriging interpolation method to generate a soil salinity surface map of the saline-alkali land to be treated, then divides the saline-alkali land to be treated into management zones based on the irrigation type, obtains a management zone map of the saline-alkali land to be treated, and obtains a soil salinity grade map within the management zone of the saline-alkali land to be treated based on the soil salinity surface map and the management zone map of the saline-alkali land to be treated, then improves a leaching irrigation quota model in combination with the wetting ratio, and obtains a soil salinity grade map within the management zone of the saline-alkali land to be treated based on the improved leaching irrigation quota model and the soil salinity grade map within the management zone of the saline-alkali land to be treated. Variable irrigation prescription map for saline-alkali land, and finally, pre-sowing treatment of the saline-alkali land to be treated is carried out based on the soil salt content grade map in the management zone of the saline-alkali land to be treated, and post-sowing treatment of the saline-alkali land to be treated is carried out based on the variable irrigation prescription map of the saline-alkali land to be treated, so as to carry out zoning and comprehensive management of the saline-alkali land. The whole process monitors the spatial distribution characteristics of soil salt in the entire farmland before sowing, and classifies light, medium and heavy saline-alkali land according to the soil salt content. The management area is divided according to the irrigation type, and variable input is made to each management area to achieve precise soil improvement and salt regulation of saline-alkali land. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a flow chart of a comprehensive saline-alkali land zoning management method; Figure 2 is the surface diagram of soil salinity; Figure 3 Management zoning map for center pivot irrigation; Figure 4 Create a logical diagram for drip irrigation management zones; Figure 5 It is a variable irrigation prescription map. DETAILED DESCRIPTION

[0016] The specific embodiments of the present invention are described below to facilitate understanding of the present invention by those skilled in the art. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the appended claims, these changes are obvious, and all inventions and creations utilizing the concepts of the present invention are protected.

[0017] like Figure 1 As shown, a method for comprehensive management of saline-alkali land by zoning includes steps S1-S4, which are specifically as follows: S1. The saline-alkali land to be treated is processed by the grid sampling method and the Kriging interpolation method to generate a surface map of the soil salinity of the saline-alkali land to be treated.

[0018] In an optional embodiment of the present invention, the present invention processes the saline-alkali land to be treated by a grid sampling method and a Kriging interpolation method to generate a surface map of the soil salinity of the saline-alkali land to be treated. The specific process is: the saline-alkali land to be treated is grid-divided, and the number of grids after division should be greater than or equal to 100. Then, a soil sample is collected at the center of the grid, and a soil sample is collected every 120° sector on a circle with a radius of 1 / 4 of the grid side length and the grid center as the circle point. The sampling depth is 20 cm. The four samples in the grid are made into a mixed sample and the soil salinity of the mixed sample is measured to obtain the soil salinity of the grid. Based on the soil salinity of the grid, the Kriging interpolation method is used to generate a surface map of the soil salinity of the saline-alkali land to be treated, as shown in FIG. Figure 2 shown.

[0019] S2. Based on the irrigation type, the saline-alkali land to be treated is divided into management zones, and a management zone map of the saline-alkali land to be treated is obtained. Furthermore, based on the soil salinity surface map and the management zone map of the saline-alkali land to be treated, a soil salinity grade map within the management zone of the saline-alkali land to be treated is obtained.

[0020] In an optional embodiment of the present invention, the irrigation types include circular sprinkler irrigation, translational sprinkler irrigation, and drip irrigation. A circular sprinkler rotates around a central axis during operation. By changing the travel speed of the sprinkler, variable irrigation in the direction of rotation is achieved, achieving the goal of regulating salt with water. When a circular sprinkler is used for irrigation, the division of management areas must take into account the travel characteristics of the sprinkler and the distribution characteristics of the water volume sprayed by the sprinkler. The saline-alkali land to be treated is divided into multiple fan-shaped management areas with the same irrigation angle along the travel direction of the sprinkler. A translational sprinkler moves parallel to a straight line, and the irrigation area is a regular rectangle. Drip irrigation is a local irrigation technology. Irrigation water is transported to the capillary tube through the main pipe and branch pipes. The water is then dripped into the saline-alkali land to be treated through the dripper on the capillary tube at the rated flow rate. The water droplets diffuse around the crop root system through gravity or capillary action. The salt will be transported with the water to the wetting front and discharged from the crop root zone.

[0021] Sprinkler variable irrigation control method: When using sprinkler irrigation (circular sprinklers and horizontal sprinklers) for variable water and salt regulation during the crop growth period, variable water supply in different management areas can be achieved by adjusting the sprinkler travel speed. When the water pressure and flow in the sprinkler pipeline are constant, the faster the travel speed, the less water is irrigated, and the slower the travel speed, the more water is irrigated.

[0022] Drip irrigation variable-rate irrigation control methods: When using drip irrigation for variable-rate water and salinity control during the crop growth period, irrigation control should be tailored to specific management zones. When land with varying salinity levels is concentrated and contiguous, management zones are divided by the area controlled by branch pipes. If drip tape specifications are uniform, irrigation quotas for mild, moderate, and severe salinity zones are calculated based on the irrigation prescription map. Different irrigation volumes are achieved by controlling the irrigation timing of branch pipes. When land with varying salinity levels is more dispersed, management zones are divided by the area controlled by a single capillary pipe. Drip tapes with the same rated pressure but different flow specifications are deployed in each management zone based on the salinity level. This allows variable-rate water and salinity control to be achieved by varying the flow rate of the capillary emitters, while ensuring consistent irrigation time within each zone. When laying drip tape, the flow rate of the emitters within each management zone increases as the salinity level increases. Designs can be made based on the irrigation quota ratios for mild, moderate, and severe salinity, selecting commercially available drip tapes that generally meet the rated pressure and flow specifications.

[0023] The present invention divides the saline-alkali land to be managed into management zones based on the irrigation type, and obtains a management zone map of the saline-alkali land to be managed, specifically: When the irrigation type is circular sprinkler irrigation, the saline-alkali land to be managed is divided into multiple fan-shaped management areas with the same irrigation angle to obtain the management zoning map of the saline-alkali land to be managed, such as Figure 3 shown.

[0024] The calculation formula for irrigation angle is:

[0025] in: is the irrigation angle, is the spraying radius of the largest nozzle of the circular sprinkler, The distance between the farthest nozzle and the center support axis in a circular sprinkler; When the irrigation type is translatory irrigation, the saline-alkali land to be treated is divided into multiple rectangular management areas with the same irrigation width. The irrigation width is set to twice the nozzle range of the translatory irrigation machine to obtain the management zoning map of the saline-alkali land to be treated. like Figure 4 As shown in the figure, when the irrigation type is drip irrigation, it is determined whether the plots with different salinization degrees in the saline-alkali land to be managed are concentrated; if so, the saline-alkali land to be managed is divided into management zones based on the control area of a single branch pipe; otherwise, the saline-alkali land to be managed is divided into management zones based on the control area of a single capillary pipe, so as to obtain the management zone map of the saline-alkali land to be managed.

[0026] The present invention obtains a soil salt content grade map within a management zone of the saline-alkali land to be treated based on a soil salt content surface map and a management zone map of the saline-alkali land to be treated. The specific process is: superimposing the soil salt content surface map of the saline-alkali land to be treated and the management zone map, respectively calculating the average soil salt content in each management zone, and determining the soil salt content grade in the management zone according to the average value, determining all management zones with the same soil salt content grade as a class of management zones, and dividing the entire saline-alkali land to be treated into three soil salt content grades of light, moderate and heavy, so as to obtain a soil salt content grade map within the management zone of the saline-alkali land to be treated.

[0027] S3. Improve the leaching irrigation quota model in combination with the wetting ratio, and obtain a variable irrigation prescription map for the saline-alkali land to be treated based on the improved leaching irrigation quota model and the soil salinity grade map within the saline-alkali land management zone to be treated.

[0028] In an optional embodiment of the present invention, the improved rinse water quota model is expressed as:

[0029] in: To manage the irrigation quota within the zone, is the wetting ratio, the sprinkler irrigation technology takes a value of 1, and the drip irrigation technology takes a value of 0.75. The planned wet layer depth is 0.2m at the seedling stage, 0.4m at the jointing stage, and 0.6m after the jointing stage. To determine the water holding capacity of saline-alkali land to be managed, is the measured soil moisture content in each management zone, To plan the depth of the elution layer, the present invention takes 0.2m. is the soil density of the planned leaching layer, is the percentage of the salt content of the planned leaching layer to the dry soil weight, The percentage of the allowable salt value of the soil in the planned leaching layer after leaching to the dry soil weight is taken as the salt tolerance threshold of corn in inland saline-alkali land. The salt removal coefficient is adjusted according to the degree of salinization and soil type. The soil type targeted by this invention is silt clay loam, and the salt removal coefficients of the mild, moderate, and severe salinization degrees are 60, 50, and 40 respectively. The evaporation and transpiration of crops during the irrigation period can be calculated using the Penman-Monteith formula. It is the effective precipitation available during the irrigation period.

[0030] The salt tolerance threshold of corn in inland saline-alkali land is shown in the following table: Table 1 Salt tolerance threshold of corn in inland saline-alkali land

[0031] The present invention calculates the irrigation quotas in different management areas through the improved leaching irrigation quota model of the above formula, and then obtains the variable irrigation prescription map of the saline-alkali land to be managed according to the irrigation quotas in different management areas, such as Figure 5 shown.

[0032] S4. Based on the soil salinity grade map within the management zone of the saline-alkali land to be managed, pre-sowing treatment is performed on the saline-alkali land to be managed, and based on the variable irrigation prescription map of the saline-alkali land to be managed, post-sowing treatment is performed on the saline-alkali land to be managed, so as to carry out comprehensive zoning management of the saline-alkali land.

[0033] In an optional embodiment of the present invention, the present invention performs pre-sowing treatment on the saline-alkali land to be treated based on the soil salinity grade map within the management zone of the saline-alkali land to be treated. Specifically, based on the soil salinity grade map within the management zone of the saline-alkali land to be treated, a set dose of organic fertilizer, desulfurization gypsum or microbial agent is applied to the saline-alkali land to be treated according to applicable conditions, and the saline-alkali land to be treated is turned over and rotary tilled to perform pre-sowing treatment on the saline-alkali land to be treated.

[0034] In the present invention, based on the soil salinity level map within the management zone of the saline-alkali land to be treated, set dosages of organic fertilizer, desulfurized gypsum or microbial agent are applied to the saline-alkali land to be treated according to applicable conditions. The specific set dosages applied are shown in the following table: Table 2 Dosage of soil conditioners applied at different soil salinity levels soil conditioner Applicable conditions Mild Moderate severe organic fertilizer Soil organic matter <1.0 g / kg 100kg / mu 150kg / mu 200kg / mu Desulfurization gypsum Soil sodium adsorption ratio>13 120kg / mu 330kg / mu 545kg / mu microbial agents The soil has a high clay content and is prone to compaction, and the soil microbial biomass is low. 20kg / mu 30kg / mu 40kg / mu The present invention deploys soil moisture sensors in three management zones: mild, moderate, and severe saline-alkali land. When the average soil moisture content in any zone reaches the set irrigation threshold, irrigation is determined. For irrigation after sowing and during the crop growth period, the present invention uses a variable irrigation prescription map for the saline-alkali land to provide a fixed irrigation quota for post-sowing treatment.

[0035] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0036] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0037] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0038] Specific embodiments are used in the present invention to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

[0039] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and it should be understood that the scope of protection of the present invention is not limited to such specific descriptions and embodiments. Those skilled in the art can make various other specific variations and combinations based on the technical teachings disclosed in the present invention without departing from the essence of the present invention, and such variations and combinations are still within the scope of protection of the present invention.

Claims

1. A method for comprehensive management of saline-alkali land by zoning, characterized in that: The following steps are involved: The saline-alkali land to be treated is processed by grid sampling method and Kriging interpolation method to generate a surface map of soil salinity of the saline-alkali land to be treated; The saline-alkali land to be treated is divided into management zones based on the irrigation type, and a management zone map of the saline-alkali land to be treated is obtained. The soil salinity level map within the management zone of the saline-alkali land to be treated is obtained based on the soil salinity surface map and the management zone map; The leaching irrigation quota model is improved by combining the wetting ratio, and the variable irrigation prescription map of the saline-alkali land to be treated is obtained based on the improved leaching irrigation quota model and the soil salinity grade map within the saline-alkali land management zone to be treated; Based on the soil salinity grade map within the management zone of the saline-alkali land to be treated, pre-sowing treatment is carried out on the saline-alkali land to be treated, and based on the variable irrigation prescription map of the saline-alkali land to be treated, post-sowing treatment is carried out on the saline-alkali land to carry out comprehensive zoning management of the saline-alkali land.

2. The method for comprehensive management of saline-alkali land by zoning according to claim 1, characterized in that: The saline-alkali land to be treated is processed by the grid sampling method and the Kriging interpolation method to generate a surface map of the soil salinity of the saline-alkali land to be treated. The specific process is: the saline-alkali land to be treated is divided into grids, and the number of grids after division should be greater than or equal to 100. Then, soil samples are collected at the center of the grid, and one soil sample is collected every 120° sector on a circle with a radius of 1 / 4 of the grid side length and the grid center as the circle point. The sampling depth is 20 cm. The four samples in the grid are made into a mixed sample, and the soil salinity of the mixed sample is measured to obtain the soil salinity of the grid. Based on the soil salinity of the grid, the Kriging interpolation method is used to generate a surface map of the soil salinity of the saline-alkali land to be treated.

3. The method for comprehensive management of saline-alkali land by zoning according to claim 1, characterized in that: Irrigation types include center pivot irrigation, lateral irrigation, and drip irrigation.

4. The method for comprehensive management of saline-alkali land by zoning according to claim 3, characterized in that: The saline-alkali land to be treated is divided into management zones based on the irrigation type, and a management zone map of the saline-alkali land to be treated is obtained, specifically: When the irrigation type is circular sprinkler irrigation, the saline-alkali land to be treated is divided into multiple sector-shaped management areas with the same irrigation angle to obtain the management zoning map of the saline-alkali land to be treated. The calculation formula for the irrigation angle is: in: is the irrigation angle, is the spraying radius of the largest nozzle of the circular sprinkler, The distance between the farthest nozzle and the center support axis in a circular sprinkler; When the irrigation type is translatory irrigation, the saline-alkali land to be treated is divided into multiple rectangular management areas with the same irrigation width. The irrigation width is set to twice the nozzle range of the translatory irrigation machine to obtain the management zoning map of the saline-alkali land to be treated. When the irrigation type is drip irrigation, determine whether the plots with different salinization degrees in the saline-alkali land to be treated are concentrated; if so, the saline-alkali land to be treated is managed and zoned based on the control area of a single branch pipe; otherwise, the saline-alkali land to be treated is managed and zoned based on the control area of a single capillary pipe, so as to obtain the management zoning map of the saline-alkali land to be treated.

5. The method for comprehensive management of saline-alkali land by zoning according to claim 1, characterized in that: Based on the soil salinity surface map and management zoning map of the saline-alkali land to be treated, the soil salinity grade map within the management zoning of the saline-alkali land to be treated is obtained. The specific process is: superimpose the soil salinity surface map and management zoning map of the saline-alkali land to be treated, calculate the average soil salinity in each management area respectively, and determine the soil salinity grade in the management area according to the size of the average value, determine all management areas with the same soil salinity grade as a type of management area, and divide the entire saline-alkali land to be treated into three types of soil salinity grades: light, moderate and heavy, to obtain the soil salinity grade map within the management zoning of the saline-alkali land to be treated.

6. The method for comprehensive management of saline-alkali land by zoning according to claim 1, characterized in that: The improved irrigation quota model is expressed as: in: To manage the irrigation quota within the zone, is the wetting ratio, the sprinkler irrigation technology takes a value of 1, and the drip irrigation technology takes a value of 0.

75. is the planned wet layer depth, is the field water holding capacity, is the measured soil moisture content in each management zone, To plan the depth of the elution layer, is the soil density of the planned leaching layer, is the percentage of the salt content of the planned leaching layer to the dry soil weight, The percentage of the allowable salt content of the planned leaching layer after leaching to the dry soil weight. is the salt removal coefficient, is the crop evaporation and transpiration water consumption during the irrigation period, It is the effective precipitation available during the irrigation period.

7. The method for comprehensive management of saline-alkali land by zoning according to claim 1, characterized in that: Based on the soil salinity grade map within the management zone of the saline-alkali land to be treated, the saline-alkali land to be treated is treated before sowing. Specifically, based on the soil salinity grade map within the management zone of the saline-alkali land to be treated, a set dose of organic fertilizer, desulfurization gypsum or microbial agent is applied to the saline-alkali land to be treated according to applicable conditions, and the soil is turned over and rotary tilled to carry out pre-sowing treatment of the saline-alkali land to be treated.

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