Double-sand fertile soil planting method for constructing root zone microdomain environment in extremely severe saline-alkali cultivated land

Abstract

The invention provides a double-sand fertile soil planting method for constructing a root zone microdomain environment in extremely severe saline-alkali cultivated land, which comprises the following steps: laying drip irrigation belts and mulching films on ridge surfaces, punching planting holes, spraying a salt blocking agent to the inner walls and the bottoms of the planting holes, laying crop planting substrates at the bottoms, and flushing to form planting pits; paving a mixed material of fine sand and bentonite in the planting pits, sowing seeds of high-stalk saline-alkaline tolerant crops, and covering the seeds with the fine sand; straws of high-stalk saline-alkaline tolerant crops are harvested to cover the furrows; seeds of the dwarf saline-alkaline tolerant crops are sown on the ridge surfaces, and straws of the dwarf saline-alkaline tolerant crops are harvested and aired on the ridge surfaces; finally, the two kinds of crop straw and the materials in the planting holes are ploughed into the soil together, and after irrigation in winter, double-sand fertile soil planting for constructing the root zone microdomain environment of the extremely severe saline-alkali cultivated land is completed. The invention further provides application of the method, and the method is used for promoting soil improvement of the extremely severe saline-alkali cultivated land, has salt-isolating and water-retaining effects, improves crop adaptability and emergence rate and reduces soil improvement cost.

Description

Technical Field

[0001] This invention belongs to the field of saline-alkali land crop planting technology, specifically involving a dual-sand fertile soil planting method for constructing a root zone microenvironment in extremely saline-alkali arable land. Background Technology

[0002] Saline-alkali land management is a key direction for improving the utilization rate of arable land resources. Methods for improving saline-alkali land, based on engineering salt drainage measures, mainly include: irrigation for salt leaching, application of organic fertilizers, soil tillage, and chemical amendments. However, conventional methods for improving saline-alkali land cannot solve the core planting problems in the early stages of severely and extremely severely saline-alkali land improvement, such as inhibited seed germination, seedling root death due to salt stress, and a sharp drop in emergence rate caused by soil compaction. This leads to poor or even no emergence rates, slow growth, and ultimately, extremely low or no crop productivity. Furthermore, the lack of crop planting significantly reduces the effectiveness of saline-alkali land improvement. The problems with conventional saline-alkali land improvement methods are as follows: (1) Conventional saline-alkali land improvement measures have a relatively long period of time to take effect and have little effect on the problem of limited crop growth and development in the early stage of improvement: Methods for improving saline-alkali farmland, such as salt removal, organic matter input (e.g., application of farmyard manure, straw, organic fertilizer), and soil conditioners, can alleviate salt stress and improve soil structure, reducing limiting factors for crop growth and development. However, because the improvement process requires a relatively long period (at least 2-3 years) to achieve noticeable results, progress can be made slowly in mildly to severely saline-alkali farmland while maintaining low productivity. In extremely severely saline-alkali farmland, crop growth and development are severely limited in the initial stages before the improvement effects are apparent.

[0003] (2) Irrigation and salt leaching measures can effectively reduce soil salinity, but they cannot reduce salt stress to the suitable planting range for crops in one go: Under the condition of ensuring smooth drainage, multiple irrigations can effectively reduce soil salinity and inhibit soil salinization. However, the amount of salt that can be washed away each time is limited, and because it needs to be combined with soil tillage and other measures, it can only be carried out 1 to 2 times a year during the off-season for crops. In mild to moderately saline-alkali farmland, it can quickly establish a good crop planting environment, but in extremely saline-alkali farmland, it is difficult to reduce the soil salinity to a suitable range for crop planting in a short period of time. In addition, irrigation can only work on the environment of salt stress and cannot solve the problem of soil structure improvement. Multiple irrigations can easily lead to soil compaction and also restrict crop growth and development.

[0004] (3) Commonly used salt-tolerant crops are only adapted to mild to moderate salt stress environments and are difficult to adapt to extremely severe salt and alkali conditions: Conventional salt-tolerant crops (such as sunflower and flax) can maintain a survival rate of >30% in moderately saline-alkali farmland, but the survival rate is extremely low in severely saline-alkali farmland. Especially in extremely severe saline-alkali farmland with a salt content of more than 1%, the survival rate of most conventional salt-tolerant crops is almost 0. Therefore, most saline-alkali farmland improvement measures do not have matching crop planting measures in the early stages of implementation, and it is also difficult to obtain crop productivity.

[0005] (4) Conventional soil amendments require large quantities of materials, which are diluted by the soil after application. Furthermore, some materials have opposing properties, and mixing them can reduce their effectiveness. Applying more organic fertilizer can significantly improve soil nutrients and structure. Soil conditioners and modifiers can regulate soil salinity and alleviate salt stress. Adding sand can reduce the impact of soil compaction on crop growth and development. However, the amount of these improvement materials applied is limited by cost and engineering volume, and the amount applied each year is limited. Even after being evenly applied to the soil, the amount retained in each area is also very small and cannot be concentrated in the crop planting area. At the same time, organic fertilizer and sand have opposite properties, and their effects on improving soil fertility and loosening the soil after being mixed will cancel each other out.

[0006] (5) Using topsoil can achieve the effects of reducing salinity, increasing fertility and improving soil structure in a short period of time, but the amount of engineering work and the cost are very high: The method of importing soil can directly replace the original soil with high salinity, poor fertility and structure with soil with low salinity, high fertility and good structure, and crops can be planted relatively quickly. However, large-scale soil importing requires large-scale engineering measures, which are costly and require a large investment of funds. This type of measure can generally only be implemented once. In the later stages, with the migration of salt and other processes, the topsoil will further become salinized, reducing the effectiveness of the soil import.

[0007] (6) Seedling transplanting can improve crop survival rate, but it has the problems of increased procedures, increased costs and high mortality rate in the later stage: In order to address the problem of seed germination rate being affected by salt stress, some improvement measures often adopt the method of transplanting seedlings in containers along with the substrate. This can improve the survival rate of crops to a certain extent, but it increases the management of seedlings, and increases the costs of seedling management, seedling materials, and seedling transplanting. Moreover, the environment changes after transplanting, and the mortality rate may increase during the subsequent growth process.

[0008] In summary, existing conventional technologies suffer from problems such as long lead times, poor crop adaptability in extremely saline-alkali conditions, large material requirements, high costs, and large engineering workload. They are not effective means to solve core planting problems in the early stages of improving severely and extremely saline-alkali farmland, such as hindered seed germination, seedling root death due to salt stress, and a sharp drop in seedling emergence rate caused by soil compaction. Summary of the Invention

[0009] The technical problem to be solved by this invention is to address the shortcomings of the prior art by providing a dual-sand fertile soil planting method for constructing root zone microenvironments in severely saline-alkali farmland. This method improves the soil locally by drilling planting holes on the ridges, ensuring that the concentration and effectiveness of the improvement materials are not reduced after application; it significantly improves the planting environment of the crop planting area; it enhances the crop's adaptability to severely saline-alkali environments and its germination rate; and it reduces the cost of improving saline-alkali farmland.

[0010] To solve the above-mentioned technical problems, the technical solution adopted by this invention is: a method for constructing a root zone microenvironment in extremely saline-alkali farmland using dual-sand fertile soil cultivation, the method being as follows: S1. Plow the extremely saline-alkali farmland, level the land, and then create ridges. The ridges reduce the accumulation of salt in the crop planting area by raising the ridge surface. The ridges can be leached and desalinated by the collection of water in the furrows during rainfall and irrigation. At the same time, the strong water evaporation process in the low-lying furrows increases the accumulation of salt that migrates with water in the furrows, which greatly reduces the degree of desalination on the ridge surface. S2. Two drip irrigation tapes are laid on each ridge surface in S1. The drip irrigation tapes and the ridge surface are covered with mulch film. After the two sides of the mulch film are fixed with soil, a mulch film-covered ridge is obtained. The mulch film can increase the temperature and humidity of the soil on the ridge surface, and prevent salt from accumulating on the ridge surface by reducing soil evaporation. As precipitation flows into the furrow along the mulch film, it reduces the erosion of the micro-environment by precipitation and has a leaching effect on the salt on the ridge side. Drip irrigation reduces irrigation water consumption and improves water use efficiency. It also blocks the path of soil salt migration with water by reducing the soil wet zone and prevents the damage of flood irrigation to the newly constructed micro-environment. S3. Drill holes in the ridges covered with plastic film obtained in S2 to obtain planting holes; S4. Spray a salt-blocking agent on the inner wall and bottom of the planting hole obtained in S3, then lay crop planting substrate at the bottom of the planting hole, and rinse the crop planting substrate with water until the surface is concave to obtain a planting pit. The salt-blocking agent is a 1% (w / w) aqueous solution of sodium carboxymethyl cellulose, sprayed at a rate of 10 mL / m³. 2 ; The salt blocking agent and crop planting substrate can provide double-layer isolation for the planting holes, effectively preventing soil salt from entering the planting holes and harming seed germination and seedling root development. At the same time, the crop planting substrate, due to its good air permeability, water retention and fertility, provides a suitable microenvironment and nutrients for crop seed germination and seedling root growth. S5. In the planting holes obtained in S4, spread a mixture of fine sand and bentonite, then sow one seed of a tall, salt-tolerant crop in each planting hole, and finally cover with fine sand. S6. After the seeds of the tall-stemmed salt-tolerant crop described in S5 germinate, carry out routine field management and irrigation, harvest the straw of the tall-stemmed salt-tolerant crop, and cover it in the furrows. S7. After the previous tall salt-tolerant crop is harvested, the seeds of the short salt-tolerant crop are sown on the ridge surface using a roller. After routine field management, the straw of the short salt-tolerant crop is harvested and placed on the ridge surface to dry. S8. The straw of the tall salt-tolerant crop covered in the furrows in S6, the straw of the short salt-tolerant crop dried in S7, and the material in the planting hole are plowed into the soil together. After plowing, salt is leached in conjunction with winter irrigation to complete the construction of the root zone microenvironment of the extremely saline-alkali farmland and the planting of the double sandy soil.

[0011] Preferably, the depth of tillage in S1 is 30cm to 35cm; the width of the ridges in S1 is 40cm to 50cm, the height of the ridges is 10cm to 15cm, and the width of the furrows is 30cm to 40cm.

[0012] Preferably, in S2, the spacing between the two drip irrigation tapes laid on each ridge is 30cm; and the width of the mulch film is 60cm.

[0013] Preferably, the diameter of the planting hole in S3 is 10cm and the depth is 10cm to 13cm. Each ridge has two rows of planting holes with a row spacing of 30cm and a hole spacing of 20cm to 30cm.

[0014] Preferably, the crop planting substrate in S4 is composed of the following raw materials in the following mass fractions: vermiculite 2.5%, peat ash 15%, perlite 17.5%, wood fiber 10%, rice husk charcoal 2.5%, vinegar residue 2.5%, coconut coir 2.5%, bentonite 2.5%, with the remainder being well-rotted farmyard manure; the thickness of the crop planting substrate is 6 cm.

[0015] Preferably, in S5, the mass ratio of fine sand to bentonite in the mixture of fine sand and bentonite is 1:1, and the amount of the mixture of fine sand and bentonite laid is 2cm away from the ridge surface; the thickness of the fine sand cover is 2cm.

[0016] Preferably, the seeds of the tall, salt-tolerant crop described in S5 are sunflower seeds.

[0017] Preferably, the irrigation described in S6 adopts drip irrigation mode, irrigating once every 5 to 7 days, with an irrigation volume of 300 mL / well.

[0018] Preferably, the seeds of the dwarf salt-tolerant crop described in S7 are barley seeds.

[0019] Preferably, the winter irrigation method described in S8 is flood irrigation.

[0020] Compared with the prior art, the present invention has the following advantages: 1. The double-sand fertile soil planting method for constructing root zone microenvironment in extremely saline-alkali farmland of the present invention, compared with the conventional overall application of improvement materials, applies improvement materials within the microenvironment of crop planting, which has the advantages of rapid effect, small input, and concentrated effect of improvement materials, and avoids the significant reduction in concentration and dispersion of the effect of improvement materials after being mixed into the soil.

[0021] 2. The double-sand fertile soil planting method for constructing root zone microenvironment in extremely saline-alkali cultivated land of the present invention reduces the seedling raising and transplanting procedures compared with the traditional container seedling raising and transplanting method. It is equivalent to raising seedlings directly in the field, allowing the crop seedlings to adapt to the growth environment in advance. The survival rate of crop seedlings will not be reduced due to changes in the environment during transplanting. At the same time, it also reduces the possibility of crop seedling waste or shortage caused by misjudging the actual planting seedling requirements, which may require supplementary seedling raising.

[0022] 3. The double-sand fertile soil planting method for constructing root zone microenvironment in extremely saline-alkali farmland of the present invention, compared with the traditional overall soil improvement measures, replaces the soil in local areas with improvement materials, which is lower in cost and requires less engineering work than conventional soil improvement.

[0023] 4. The double-sand fertile soil planting method for constructing root zone microenvironment in extremely saline-alkali arable land of the present invention can be applied in the early stage of extremely saline-alkali land improvement, and crops can be planted in the same year, which greatly shortens the saline-alkali land improvement cycle and improves the efficiency of saline-alkali arable land improvement compared with conventional planting methods.

[0024] 5. The double-sand fertile soil planting method for constructing root zone microenvironments in extremely saline-alkali farmland of the present invention adopts a planting method of ridge planting + drip irrigation under film. The ridge surface is the main site for constructing the root zone microenvironment. The root zone microenvironment constructed on the ridge can fully gather the advantages of light, temperature, water and heat conditions of ridge planting and avoid saline-alkali damage. The drip irrigation under film can ensure the temperature and water conditions of the root zone microenvironment while avoiding the damage to the root zone microenvironment caused by frequent irrigation and flood irrigation.

[0025] 6. The double-sand fertile soil planting method for constructing root zone microenvironment in extremely saline-alkali farmland of the present invention isolates the environment inside the planting hole from the external saline soil by drilling planting holes on the ridge, spraying an inhibitor inside the planting hole and laying crop planting substrate at the bottom, thus creating a microenvironment conducive to crop seed development and crop root growth; at the same time, the crop planting substrate also undertakes core functions such as crop nutrient supply, root attachment, aeration and water retention.

[0026] 7. This invention relates to a double-sand fertile soil planting method for constructing a root zone microenvironment in extremely saline-alkali farmland. Crops are planted between two sand layers, creating a suitable environment as a good seedbed for crop seed germination. The upper fine sand layer provides a loose and breathable environment for seed germination, which is conducive to seedling emergence. The lower sandy layer mainly utilizes the loose environment to promote the growth of crop seedling roots, and the large porosity and weak capillary lift slow down the accumulation of soil salts. After being mixed with bentonite, the water retention and fertilizer performance are improved. It forms a barrier with the lower crop planting substrate layer to avoid excessive nutrient concentration burning the seedlings, and also ensures the slow release of nutrients, promoting the absorption of nutrients by crop roots, so that the crop emergence rate is as high as 95% or more.

[0027] 8. The present invention provides a dual-sand fertile soil planting method for constructing root zone microenvironment in severely saline-alkali farmland. This method involves a dual-coverage straw return method, which uses long-term covering of tall crop straw in furrows and short-term covering of short crop straw on ridge surfaces. This method utilizes locally sourced straw for surface covering in non-crop planting areas, reducing soil evaporation and salt accumulation. After the straw from both crops has fully degraded, it is returned to the field along with the crop planting substrate, increasing the types and amounts of organic matter input into the saline-alkali farmland soil.

[0028] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the double-sand fertile soil planting method for constructing root zone microenvironment in extremely saline-alkali cultivated land according to Embodiment 1 of the present invention. Detailed Implementation

[0030] Example 1 This embodiment describes a dual-sand-fertile soil planting method for constructing root zone microenvironments in severely saline-alkali farmland, as illustrated in the diagram below. Figure 1 As shown, the method is as follows: S1. Till the extremely saline-alkali farmland soil to break up the soil compaction layer and loosen the soil. The tillage depth is 30cm to 35cm. Then level the land and ensure that the relative height difference of the field surface is controlled within ±5cm. Divide the soil into different plots according to different planting needs. In each plot, use manual methods to make ridges. The ridge width is 40cm to 50cm, the ridge height is 10cm to 15cm, and the furrow width is 30cm to 40cm. The ridges reduce the accumulation of salt in the crop planting area by raising the ridge surface. The ridges can be leached and desalinated by the collection of water in the furrows during rainfall and irrigation. At the same time, the strong water evaporation process in the low-lying furrows increases the accumulation of salt that migrates with water in the furrows, which greatly reduces the degree of desalination on the ridge surface. S2. Two drip irrigation tapes are laid on each ridge surface in S1, with a spacing of 30cm between the drip irrigation tapes. The drip irrigation tapes and the ridge surface are covered with 60cm wide mulch film. The parts of the mulch film that extend beyond the ridge surface on both sides are compacted and fixed with soil shoveled from the furrow. When laying the mulch film, it is necessary to ensure that the mulch film is tightly attached to the ridge surface without wrinkles, so as to obtain a ridge covered with mulch film. The mulch film can increase the temperature and humidity of the soil on the ridge surface, and prevent salt from accumulating on the ridge surface by reducing soil evaporation. As precipitation flows into the furrow along the mulch film, it reduces the erosion of the micro-environment by precipitation and has a leaching effect on the salt on the ridge side. Drip irrigation reduces irrigation water consumption and improves water use efficiency. It also blocks the path of soil salt migration with water by reducing the soil wet zone and prevents the damage of flood irrigation to the newly constructed micro-environment. S3. On the ridges covered with plastic film obtained in S2, holes with a depth of 10cm to 13cm are drilled using a drilling device with a crossbar length of 1m, a handle length of 20cm, and a hole diameter of 10cm to obtain planting holes. Two rows of planting holes with a row spacing of 30cm and a hole spacing of 20cm to 30cm are distributed on each ridge. The planting holes coincide with the position of the drip irrigation head of the drip irrigation tape. S4. Spray a salt-blocking agent on the inner wall and bottom of the planting hole obtained in S3, and then lay a 6cm thick crop planting substrate at the bottom of the planting hole. Rinse the crop planting substrate with water until the surface is concave to obtain a planting pit. The salt-blocking agent is a 1% (w / w) aqueous solution of sodium carboxymethyl cellulose, sprayed at a rate of 10 mL / m³. 2 ; The crop planting substrate is composed of the following raw materials in the indicated mass fractions: vermiculite 2.5%, peat ash 15%, perlite 17.5%, wood fiber 10%, rice husk charcoal 2.5%, vinegar residue 2.5%, coconut coir 2.5%, bentonite 2.5%, with the remainder being well-rotted farmyard manure. The salt blocking agent and crop planting substrate can provide double-layer isolation for the planting holes, effectively preventing soil salt from entering the planting holes and harming seed germination and seedling root development. At the same time, the crop planting substrate, due to its good air permeability, water retention and fertility, provides a suitable microenvironment and nutrients for crop seed germination and seedling root growth. S5. In the planting holes obtained in S4, spread a mixture of fine sand and bentonite (Hebei Longqing Biotechnology Co., Ltd.) in a mass ratio of 1:1. The amount of fine sand and bentonite mixture should be spread until it is 2cm away from the ridge surface. Then, sow one sunflower seed in each planting hole and finally cover it with fine sand to a thickness of 2cm. After S6 and 10 days, the sunflower seeds described in S5 will emerge and be managed in a conventional field. Drip irrigation will be used for irrigation, once every 5 to 7 days, with a water volume of 300 mL / hole, aiming to moisten the planting hole and prevent water from overflowing the planting hole, which would cause salt to erode the microenvironment. The harvested sunflower stalks will be used to cover the furrows and can be used as green manure for returning to the field. S7. After the sunflowers mentioned above are harvested, barley seeds are sown on the ridge surface using a roller. After routine field management, the harvested barley straw is placed on the ridge surface to dry and can be used as green manure for returning to the field. S8. The sunflower stalks used to cover the furrows in S6, the dried barley stalks from S7, and the materials from the planting holes are all plowed into the soil. After plowing, salt leaching is carried out in conjunction with winter irrigation using a flood irrigation method, with an irrigation volume of approximately 150m³. 3 / mu, completing the construction of root zone microenvironment in the Shuangsha Fertile Soil planting on extremely saline-alkali farmland.

[0031] Examples 2 to 7 are specific implementation processes of Example 1.

[0032] Hongyue Village, Caowotan Town, Jingtai County, was chosen as the experimental site. Located in the central part of Jingtai County, in the heart of the Jingdian Phase I Yellow River Diversion and Irrigation Project, 8 km north of the county seat and 3 km east of Caowotan Town, the area is a small basin sloping from southwest to northeast, with an elevation of 1565 m. The climate is dry, arid, and windy with little rainfall. The average annual precipitation is 185 mm, with little interannual variation, concentrated between July and September. The annual evaporation is 3040 mm, and the average annual temperature is 8.5℃. Rainfall and heat occur simultaneously. Surface water resources are scarce, while groundwater resources are highly mineralized and of poor quality. The Jingdian Phase I and II high-lift electric Yellow River Diversion and Irrigation Projects, built in the 1970s and 1980s, are the main water source for the area. However, the unique geological features, parent material, climate, and inappropriate irrigation have resulted in severe secondary soil salinization. The village currently has 330.7 hm² of arable land. 2 Approximately 80% of the farmland is secondary salinized land. The soil parent material type in this study area is consistent, with the zonal soil being desert gray-calcareous soil. The soil parent material includes loess, aeolian deposits, and alluvial deposits, and the groundwater level is around 1 meter.

[0033] Example 2 This embodiment measures the degree of soil salinization and soil fertility in the experimental site.

[0034] In October 2024, soil survey sampling was carried out in the salinized soil improvement area of ​​Hongyue Village, Caowotan Town, Jingtai County. Sampling points were set up in a spatially uniform manner. Soil samples were collected from the surface and profile at the sampling points using a soil auger. In the laboratory, the water content, pH, electrical conductivity, total salt and organic matter content of the soil surface (0cm to 10cm) were measured to determine the degree of soil salinization and soil fertility in the experimental area.

[0035] The average surface soil moisture content was 17.21%, higher on the west side of the verification site, but higher in the central and eastern parts of the subsoil. The soil was heavy and moist, with poor drainage and significant salinization. The average surface soil pH was 9.15. The surface soil electrical conductivity was 10.35 dS / m, far exceeding the standard for severely salinized soil (1.84 dS / m to 2.90 dS / m), classifying it as saline soil (>2.90 dS / m). The surface soil salt content was 20.27‰, mainly composed of sulfates and chlorides. The surface soil organic matter content was 7.90 g / kg, indicating that this soil was extremely severely salinized.

[0036] Example 3 This embodiment compares the changes in soil salinity after the underground pipe salt drainage project to determine the soil salinity improvement status after the project.

[0037] In 2024, a subsurface pipe salt drainage project was carried out in the saline soil improvement area of ​​Hongyue Village, Caowotan Town, Jingtai County. After two rounds of salt drainage during winter and spring irrigation, soil samples were collected again on March 12 and June 15, 2025. The laboratory analyzed soil moisture content, pH, electrical conductivity, salinity and other indicators to determine the improvement effect of the subsurface pipe salt drainage project on saline soil.

[0038] As shown in Table 1, the soil electrical conductivity and salt content were significantly reduced by the underground pipe salt drainage project combined with two irrigations in winter and spring, but the soil is still classified as extremely saline-alkali soil.

[0039] Table 1 Comparison of soil characteristics before and after the underground pipe salt drainage project in the experimental area Example 4 This embodiment compares the effects of ridge cultivation combined with drip irrigation under mulch on the electrical conductivity, temperature, and moisture of the soil surface layer (0cm–10cm), aiming to clarify the salt reduction and water retention effects of ridge cultivation combined with drip irrigation under mulch. The specific experimental design is as follows: On April 15, 2025, a plot experiment was conducted in the saline soil improvement area of ​​Hongyue Village, Caowotan Town, Jingtai County. Two treatments were set up: flat cropping and ridge cropping with drip irrigation under mulch. Each plot covered an area of ​​5 mu. On August 17, 2025, the surface soil moisture content, conductivity, and temperature of the flat cropping and ridge cropping were measured using a portable soil moisture, temperature and conductivity meter (TDR 350) to clarify the salt reduction and water retention effect of ridge cropping with drip irrigation under mulch.

[0040] As shown in Table 2, the surface soil moisture content of the ridged surface was 19.5% higher than that of the flat ground, the surface soil electrical conductivity of the ridged surface was 16.7% lower than that of the flat ground, and the surface soil temperature of the ridged surface was 3.99℃ higher than that of the flat ground.

[0041] Table 2. Effects of flat planting, ridge planting + drip irrigation under mulch on soil surface moisture content, electrical conductivity and temperature. Example 5 This embodiment compares the differences in soil moisture content, electrical conductivity, and temperature inside and outside the planting hole to clarify the isolation effect of the planting hole isolation layer.

[0042] In 2025, a planting experiment was conducted in the saline soil improvement area of ​​Hongyue Village, Caowotan Town, Jingtai County. The crop was planted using the Shuangsha Fertile Soil planting method, which constructs a root zone microenvironment in extremely saline-alkali farmland. The crop planted was sunflower. The sunflowers were sown on April 20. On August 17, 10 plants were randomly selected in the experimental plot. Soil moisture content, electrical conductivity and temperature were measured inside and outside the planting hole to determine the isolation effect of the planting hole.

[0043] As shown in Table 3, the average soil moisture content inside the planting hole was 40.4% higher than that outside the planting hole, the average soil electrical conductivity inside the planting hole was 85.5% lower than that outside the planting hole, and the soil temperature inside the planting hole was 0.2℃ lower than that outside the planting hole.

[0044] Table 3. Measurement of soil moisture content, electrical conductivity, and temperature inside and outside the planting hole. Example 6 This embodiment compares the differences in crop emergence rates under different planting patterns to clarify the actual effect of the root zone microenvironment construction method on promoting crop growth.

[0045] In 2025, a small-plot experiment was conducted in the saline-alkali soil improvement area of ​​Hongyue Village, Caowotan Town, Jingtai County. Five treatments were set up: traditional planting, ridge planting with mulch, drip irrigation with mulch, planting through planting holes, and micro-environment planting (ridge planting + drip irrigation under mulch + planting holes). All other planting and management conditions were the same. Sunflower seeds were sown on April 20 and replanted in areas where seedlings had not yet emerged on July 15 to clarify the actual effect of the root zone micro-environment construction method on promoting crop growth.

[0046] As shown in Table 4, the germination rate after the first sowing was highest with the root zone microenvironment construction method, reaching 95%, followed by flat planting holes, drip irrigation with mulch, and ridge planting with mulch, at 30%, 15%, and 9% respectively, while the germination rate of the traditional method was 0%. After replanting, the germination rate of the root zone microenvironment construction method reached 100%, while the germination rates of flat planting holes, drip irrigation with mulch, and ridge planting with mulch were 40%, 23%, and 16% respectively, while the germination rate of the traditional method was 2%. The survival rate after irrigation was basically the same as the germination rate. After planting with flat planting holes, flood irrigation was used, and the survival rate after flood irrigation was 0%. The germination rate of microenvironment planting increased from 0-2% to 95%-100%. If flood irrigation was used instead of ridge irrigation or drip irrigation, the survival rate of the crops after germination would decrease to 0%.

[0047] Table 4 Crop emergence rate under different planting patterns Later, the harvested sunflower stalks can be used to cover the furrows as green manure. After the sunflowers of the previous crop are harvested, barley seeds are sown on the ridges using rollers. After routine field management, the harvested barley stalks are laid out on the ridge surface to dry and can be used as green manure. Finally, the stalks and the materials from the planting holes can be plowed into the soil together. After plowing, salt leaching is carried out in conjunction with winter irrigation. A flood irrigation method can be used to complete the construction of a root zone microenvironment in extremely saline-alkali farmland using the Shuangsha Fertile Soil method.

[0048] Example 7 This embodiment illustrates the differences in economic input costs under different planting models, clarifying the actual effect of the root zone microenvironment construction method in saving costs.

[0049] In 2025, a plot experiment was conducted in the saline soil improvement area of ​​Hongyue Village, Caowotan Town, Jingtai County. Two treatments were set up: the traditional improvement method (i.e., applying improvement materials such as organic fertilizer, substrate, bentonite, and fine sand into the soil in one go) and the micro-environment planting improvement method. The input cost of different soil improvement methods was calculated by calculating the input of labor and improvement materials, so as to clarify the actual effect of the root zone micro-environment construction method in saving costs.

[0050] As shown in Table 5, the micro-domain environment construction method requires 210 yuan / mu more in labor costs than the traditional improvement method; as shown in Table 6, the material input cost of the micro-domain environment construction method is 282.5 yuan / mu, which is 63.3% lower than the traditional improvement method; in summary, the total input cost of the micro-domain environment construction method is 492.5 yuan / mu, which is 36.0% lower than the traditional improvement method.

[0051] Table 5. Estimation of additional labor costs for the root region micro-domain environment construction method. Table 6. Comparison of material costs between traditional improvement methods and the construction of root region microenvironments. The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the inventive essence shall still fall within the protection scope of the present invention.

Claims

1. A method for constructing a root zone microenvironment in extremely saline-alkali farmland using a dual-sand-fertile soil planting system, characterized in that... The method is as follows: S1. Plow the extremely saline-alkali farmland, level the land, and then create ridges. S2. Two drip irrigation tapes are laid on each ridge surface in S1. The drip irrigation tapes and the ridge surface are covered with mulch film. After the two sides of the mulch film are fixed with soil, a mulch film-covered ridge is obtained. S3. Drill holes in the ridges covered with plastic film obtained in S2 to obtain planting holes; S4. Spray a salt-blocking agent on the inner wall and bottom of the planting hole obtained in S3, then lay crop planting substrate at the bottom of the planting hole, and rinse the crop planting substrate with water until the surface is concave to obtain a planting pit. The salt-blocking agent is a 1% (w / w) sodium carboxymethyl cellulose aqueous solution, sprayed at a rate of 10 mL / m³. 2 ; S5. In the planting holes obtained in S4, spread a mixture of fine sand and bentonite, then sow one seed of a tall, salt-tolerant crop in each planting hole, and finally cover with fine sand. S6. After the seeds of the tall-stemmed salt-tolerant crop described in S5 have emerged, carry out routine field management and irrigation, harvest the straw of the tall-stemmed salt-tolerant crop, and cover it in the furrows. S7. After the previous tall salt-tolerant crop is harvested, the seeds of the short salt-tolerant crop are sown on the ridge surface using a roller. After routine field management, the straw of the short salt-tolerant crop is harvested and placed on the ridge surface to dry. S8. The straw of the tall salt-tolerant crop covered in the furrows in S6, the straw of the short salt-tolerant crop dried in S7, and the material in the planting hole are plowed into the soil together. After plowing, salt is leached in conjunction with winter irrigation to complete the construction of the root zone microenvironment of the extremely saline-alkali farmland and the planting of the double sandy soil.

2. The method for constructing a root zone microenvironment in extremely saline-alkali farmland using a dual-sand-fertile soil planting system according to claim 1, characterized in that, The tillage depth in S1 is 30cm to 35cm; the ridge width in S1 is 40cm to 50cm, the ridge height is 10cm to 15cm, and the furrow width is 30cm to 40cm.

3. The method for constructing a root zone microenvironment in extremely saline-alkali farmland using a dual-sand-fertile soil planting system according to claim 1, characterized in that, The spacing between the two drip irrigation tapes laid on each ridge in S2 is 30cm; the width of the mulch film is 60cm.

4. The method for constructing a root zone microenvironment in extremely saline-alkali farmland using a dual-sand-fertile soil planting system according to claim 1, characterized in that, The planting holes described in S3 have a diameter of 10cm and a depth of 10cm to 13cm. Each ridge has two rows of planting holes with a row spacing of 30cm and a hole spacing of 20cm to 30cm between each row.

5. The method for constructing a root zone microenvironment in extremely saline-alkali farmland using a dual-sand-fertile soil planting system according to claim 1, characterized in that... The crop planting substrate described in S4 is composed of the following raw materials in the following mass fractions: vermiculite 2.5%, peat ash 15%, perlite 17.5%, wood fiber 10%, rice husk charcoal 2.5%, vinegar residue 2.5%, coconut coir 2.5%, bentonite 2.5%, with the remainder being well-rotted farmyard manure; the thickness of the crop planting substrate is 6cm.

6. The method for constructing a root zone microenvironment in extremely saline-alkali farmland using a dual-sand-fertile soil planting system according to claim 1, characterized in that, In S5, the mass ratio of fine sand to bentonite in the mixture of fine sand and bentonite is 1:1, and the mixture of fine sand and bentonite is laid until it is 2cm away from the ridge surface; the thickness of the fine sand cover is 2cm.

7. The method for constructing a root zone microenvironment in extremely saline-alkali farmland using a dual-sand-fertile soil planting system according to claim 1, characterized in that, The seeds of the tall, salt-tolerant crop described in S5 are sunflower seeds.

8. The method for constructing a root zone microenvironment in extremely saline-alkali farmland using a dual-sand-fertile soil planting system according to claim 1, characterized in that, The irrigation described in S6 adopts drip irrigation mode, and irrigation is carried out once every 5 days to 7 days, with an irrigation volume of 300 mL / well.

9. The method for constructing a root zone microenvironment in extremely saline-alkali farmland using a dual-sand-fertile soil planting system according to claim 1, characterized in that, The seeds of the short-statured, salt-tolerant crop mentioned in S7 are barley seeds.

10. The method for constructing a root zone microenvironment in extremely saline-alkali farmland using a dual-sand-fertile soil planting system according to claim 1, characterized in that, The winter irrigation method described in S8 is flood irrigation.

Images