Method for improving saline-alkali soil by combining impermeable membrane with soil replacement backfilling

Abstract

The invention relates to the technical field of saline-alkali soil improvement, and discloses a saline-alkali soil improvement method by combining an anti-osmosis membrane with soil replacement backfill, and the method comprises the following steps: determining the height of soil replacement and the gradient of the slope of a foundation pit, and digging the foundation pit in saline-alkali soil; laying an anti-permeation membrane on the surface of the foundation pit; a first hole is formed in the bottom of the anti-osmosis membrane, and the first hole is communicated with a drainage pipe; and filling the accommodating space formed by the anti-osmosis membrane with the soil dressing. The technical problem that the maintenance cost is high after saline-alkali soil is treated through a soil dressing backfilling method is solved.

Description

Technical Field

[0001] The present application relates to the technical field of saline-alkali land soil improvement, and in particular to a saline-alkali land soil improvement method using an anti-permeability membrane combined with imported soil backfilling. Background Art

[0002] Salt-alkali land management is a key technical field to improve the quality of cultivated land and ensure food security. At present, the main management measures include engineering measures and chemical measures. Engineering measures have gradually become the mainstream technical direction due to their significant salt control effect and decades of validity.

[0003] In the related technology, the method of backfilling with imported soil is used to treat saline-alkali land, that is, the cultivated soil is taken to raise the ground to achieve the purpose of isolating salt from the cultivated layer. However, after the saline-alkali land is treated with the backfilling with imported soil method, other engineering measures and agricultural measures are required to maintain and repair the backfilled imported soil to prevent the imported soil from being salinized again, and the subsequent maintenance cost is high. Summary of the invention

[0004] The present application provides a saline-alkali land soil improvement method using an anti-permeability membrane combined with imported soil backfilling, which solves the technical problem of high maintenance cost after the saline-alkali land is treated by the imported soil backfilling method.

[0005] In order to achieve the above objectives, the main technical solutions adopted in this application include:

[0006] An embodiment of the present application provides a method for improving saline-alkali land soil by using an anti-permeability membrane combined with imported soil backfill, the method comprising: determining the height of the imported soil and the slope of the foundation pit slope, and digging a foundation pit in the saline-alkali land; laying an anti-permeability membrane on the surface of the foundation pit; opening a first hole at the bottom of the anti-permeability membrane, and connecting the first hole to a drainage pipe; and filling the imported soil into the accommodation space formed by the anti-permeability membrane.

[0007] The method for improving saline-alkali land soil by using an anti-permeability membrane combined with imported soil backfill proposed in the embodiment of the present application has an anti-permeability membrane arranged between the foundation pit and the imported soil, which can prevent the salt in the saline-alkali land from penetrating into the imported soil, avoid the re-salinization of the imported soil, and further improve the saline-alkali land, so that crops can survive in the saline-alkali land for a long time.

[0008] Optionally, determining the height of the added soil and the slope of the foundation pit slope includes: determining that the height of the added soil is not less than 0.5 m, and determining that the slope of the foundation pit slope is not greater than 60°.

[0009] The height of the imported soil is not less than 0.5 m, which can ensure the formation of a high-quality soil layer with sufficient thickness in the saline-alkali land. The sufficient thickness of the imported soil can provide sufficient growth space for the roots of crops, enabling them to take root and absorb nutrients and water, thereby creating a relatively good soil environment for crop growth, improving the survival rate and growth conditions of crops, and meeting the basic needs of crop planting. The slope of the foundation pit slope is not greater than 60°, making the slope of the foundation pit relatively gentle, which is conducive to preventing unstable phenomena such as landslides and collapses of the slope soil under the action of gravity, and ensuring the structural stability of the foundation pit during the imported soil backfilling and subsequent use process.

[0010] Optionally, laying the anti-seepage membrane on the surface of the foundation pit includes: cleaning sundries such as sharp stones on the surface of the foundation pit; closely attaching the anti-seepage membrane to the surface of the foundation pit; laying non-woven fabric vertically between the anti-seepage membrane and the surface of the foundation pit and above the anti-seepage membrane.

[0011] Laying non-woven fabric vertically between the anti-seepage membrane and the surface of the foundation pit and above the anti-seepage membrane. On the one hand, the non-woven fabric is soft in texture and can play a buffering and protective role between the anti-seepage membrane and the surface of the foundation pit, and between the anti-seepage membrane and the imported soil, preventing the anti-seepage membrane from being scratched by sharp particles. On the other hand, the non-woven fabric has good water permeability and air permeability, does not hinder the passage of water, and can effectively prevent fine particles in the imported soil from entering the drain pipe and causing blockage, helping to drain excess water in time and avoiding waterlogging of the imported soil.

[0012] Optionally, closely attaching the anti-seepage membrane to the surface of the foundation pit includes: controlling the distance between the edge of the anti-seepage membrane and the upper edge of the foundation pit to be not less than 40 cm; digging a first annular groove at a distance of 20 cm from the upper edge of the foundation pit, and the distance between the bottom surface of the first annular groove and the surface of the saline-alkali land is not less than 20 cm; burying the saline-alkali soil dug from the foundation pit in the saline-alkali land into the first annular groove to press the anti-seepage membrane and the bottom surface of the first annular groove.

[0013] Digging a first annular groove at a distance of not less than 20 cm from the upper edge of the foundation pit. The first annular groove surrounds the foundation pit, and then bury the saline-alkali soil dug from the foundation pit into the first annular groove, and then press the anti-seepage membrane and the bottom of the first annular groove tightly, so that the two are closely attached. In this way, the position of the anti-seepage membrane can be fixed, effectively preventing the anti-seepage membrane from moving or loosening due to external force pulling and soil movement, ensuring that the anti-seepage membrane is in a stable working state for a long time, and preventing the imported soil from being re-salinized.

[0014] Optionally, laying the anti-seepage membrane on the surface of the foundation pit further includes: laying a 5-cm fine sand layer above the non-woven fabric to press the anti-seepage membrane and the bottom of the foundation pit.

[0015] Lay a 5-cm-thick fine sand layer above the non-woven fabric to press the anti-seepage membrane against the bottom of the foundation pit. On the one hand, the fine sand layer can press the anti-seepage membrane against the bottom of the foundation pit, making the anti-seepage membrane fit more closely with the bottom of the foundation pit. On the other hand, the fine sand layer is located between the native soil and the anti-seepage membrane, which can prevent sharp impurities in the native soil from piercing the anti-seepage membrane, enhancing the stability and reliability of the anti-seepage membrane during use.

[0016] Optionally, a first hole is opened at the bottom of the anti-seepage membrane and connected to the drain pipe. Specifically: a first hole is opened at the bottom of the anti-seepage membrane to connect the first hole with the drain pipe; a filter cover is arranged at one end of the first hole facing the anti-seepage membrane to prevent impurities such as sediment from entering the drain pipe.

[0017] There is a first hole at the bottom of the anti-seepage membrane. The first hole penetrates through both ends of the anti-seepage membrane in the vertical direction. A filter cover is arranged at one end of the first hole facing the anti-seepage membrane, which can effectively intercept impurities such as sediment and fine particles in the native soil and prevent them from entering the drain pipe and causing blockage, maintaining the smoothness of the drain pipe, enabling the timely discharge of excess water in the native soil, and avoiding the occurrence of waterlogging in the native soil.

[0018] Optionally, one end of the drain pipe is connected to the first hole, and the other end of the drain pipe is connected to the drainage well. The distance between the bottom of the drainage well and the bottom surface of the foundation pit is not less than 0.5 m.

[0019] The distance between the bottom of the drainage well and the bottom of the foundation pit is not less than 0.5 m, ensuring that the drainage well has enough depth to accommodate water, avoiding the backflow of accumulated water into the foundation pit due to the shallowness of the drainage well, and ensuring the continuous and efficient discharge of excess water to maintain a good growth environment for crops.

[0020] Optionally, when the depth of the accumulated water in the drainage well is higher than 1 / 4 of the height of the native soil, use a water pump to pump out the accumulated water in the well.

[0021] When the depth of the accumulated water in the drainage well is higher than 1 / 4 of the height of the native soil, use a water pump to pump out the accumulated water in the well. In this way, the accumulated water in the drainage well can be pumped out in time, avoiding the long-term immersion of the native soil by the accumulated water.

[0022] Optionally, fill the native soil into the accommodation space formed by the anti-seepage membrane. Specifically: fill the native soil into the accommodation space formed by the anti-seepage membrane, control the height of the native soil to be not less than 0.15 m higher than the height of the foundation pit; control the upper surface of the native soil to be flat and parallel to the upper surface of the saline-alkali land.

[0023] Controlling the height of the native soil to be not less than 0.15 m higher than the height of the foundation pit can prevent the loss of the native soil caused by factors such as weathering and rain erosion, and moreover, the higher height of the native soil is also beneficial to the full growth of crop roots.

[0024] Optionally, ridges are provided in the part of the imported soil that is higher than the height of the foundation pit to drain rainwater from the imported soil filling area.

[0025] Providing ridges in the part of the imported soil that is higher than the height of the foundation pit to drain rainwater from the imported soil filling area can keep the imported soil in good condition, thereby ensuring the effective growth of crops. Description of the Drawings

[0026] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0027] Figure 1 It is a schematic flow chart of a saline-alkali soil improvement method using an anti-seepage membrane combined with imported soil backfilling provided by an embodiment of the present application;

[0028] Figure 2 It shows the structure of the foundation pit and the anti-seepage membrane;

[0029] Figure 3 It shows the structural relationship among the imported soil, the foundation pit and the anti-seepage membrane;

[0030] Figure 4 It is a schematic structural diagram provided by Embodiment 1 of the present application.

[0031]

Description of the Reference Numerals

[0032] Imported soil 100; Ridge 101;

[0033] Foundation pit 110;

[0034] Anti-seepage membrane 120;

[0035] First hole 130;

[0036] First annular groove 140;

[0037] Filter cover 150;

[0038] Drain pipe 160;

[0039] Drainage well 170. Detailed Embodiments

[0040] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will clearly and completely describe the technical solutions in the embodiments of this application with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, rather than all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of this application.

[0041] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification and claims of this application or the above drawings are used to distinguish different objects and are not used to describe a specific order or primary-secondary relationship.

[0042] Referring to "embodiments" in this application means that specific features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of this application. The phrase appearing in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0043] In the description of this application, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "connected to", and "attached" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] The term "and / or" in this application is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally represents an "or" relationship between the associated objects before and after.

[0045] The term "multiple" appearing in this application refers to two or more (including two). Similarly, "multiple groups" refers to two or more groups (including two groups), and "multiple pieces" refers to two or more pieces (including two pieces).

[0046] Saline-alkali land treatment is a key technical field for improving cultivated land quality and ensuring food security. Currently, the main treatment measures include two categories: engineering measures and chemical measures. Engineering measures have gradually become the mainstream technical direction due to their significant salt control effect and the advantage of a validity period of up to several decades.

[0047] The core technologies of engineering measures cover two categories: subsurface pipe drainage for salt removal and replacement soil backfilling. The former removes salt and reduces soil salinity through an underground pipe system, while the latter achieves physical salt isolation by replacing the cultivated soil layer. However, the replacement soil backfilling technology has significant ecological and economic risks. This technology requires a large amount of high-quality soil (mature soil) to be transported from outside and covered on the surface of saline-alkali land. Although it can block the upward movement of salt in the short term, it has extremely strong ecological destructiveness to the soil source area. With large-scale promotion, high-quality soil sources are becoming increasingly scarce, and it has faced the dilemma of "no soil available for backfilling".

[0048] In related technologies, when using the replacement soil backfilling method to treat saline-alkali land, the salt in the saline-alkali land can easily enter the replacement soil in multiple directions (horizontal or vertical). Therefore, other engineering measures and agricultural measures need to be adopted to maintain and repair the replacement soil after backfilling to prevent the replacement soil from being salinized again, resulting in high post-maintenance costs.

[0049] In view of this, the embodiments of the present application propose a saline-alkali land soil improvement method using an anti-seepage membrane combined with replacement soil backfilling. The method includes: determining the height of the replacement soil and the slope of the foundation pit slope, and excavating a foundation pit in the saline-alkali land; laying an anti-seepage membrane on the surface of the foundation pit; opening a first hole at the bottom of the anti-seepage membrane and connecting the first hole to a drainage pipe; filling the replacement soil into the accommodation space formed by the anti-seepage membrane.

[0050] In the above solution, the saline-alkali land soil improvement method using an anti-seepage membrane combined with replacement soil backfilling proposed by the embodiments of the present application is provided with an anti-seepage membrane between the foundation pit and the replacement soil, which can prevent the salt in the saline-alkali land from penetrating into the replacement soil, avoid the replacement soil from being salinized again, and thus improve the saline-alkali land, enabling crops to survive in the saline-alkali land for a long time.

[0051] For the convenience of description, the following embodiments will be described by taking the saline-alkali land soil improvement method using an anti-seepage membrane combined with replacement soil backfilling in an embodiment of the present application as an example.

[0052] Figure 1 It is a flow schematic diagram of the saline-alkali land soil improvement method using an anti-seepage membrane combined with replacement soil backfilling provided by the embodiments of the present application; Figure 2 It shows the structure of the foundation pit and the anti-seepage membrane; Figure 3 It shows the structural relationship among the replacement soil, the foundation pit, and the anti-seepage membrane; Figure 4 It is a structural schematic diagram provided by Embodiment 1 of the present application.

[0053] Please refer to Figures 1 to 3, in this embodiment, a method for improving saline-alkali soil by using an anti-seepage membrane 120 combined with imported soil 100 includes:

[0054] S100. Determine the height of the imported soil 100 and the slope of the inclined surface of the foundation pit 110, and dig out the foundation pit 110 in the saline-alkali soil;

[0055] The imported soil 100, as the name implies, is also backfill soil. In this embodiment, the imported soil 100 refers to the soil transferred from a better or fertile soil in a normal ecosystem to the saline-alkali soil, and the transferred imported soil 100 is used for planting. Determine the height of the imported soil 100 and the slope of the inclined surface of the foundation pit 110. The height of the imported soil 100 corresponds to the height of the foundation pit 110. The height of the imported soil 100 can be slightly higher than the height of the foundation pit 110. Then, according to the determined height of the imported soil 100 and the slope of the inclined surface of the foundation pit 110, dig out the corresponding foundation pit 110 in the saline-alkali soil.

[0056] S200. Lay the anti-seepage membrane 120 on the surface of the foundation pit 110;

[0057] The anti-seepage membrane 120 can be a high-density polyethylene anti-seepage membrane 120 (HDPE membrane). The HDPE anti-seepage membrane 120 has extremely low permeability and can effectively prevent the leakage of liquid. The anti-seepage membrane 120 can prevent the leakage of salts. Lay the anti-seepage membrane 120 on the surface of the foundation pit 110, that is, closely attach the anti-seepage membrane 120 to the surface of the foundation pit 110. In this way, the salts in the saline-alkali soil cannot pass through the anti-seepage membrane 120 and enter the imported soil 100, which can avoid the re-salinization of the imported soil 100 by the salts in the saline-alkali soil.

[0058] Exemplarily, the anti-seepage membrane 120 can be composed of multiple sub anti-seepage membranes 120 spliced together. The multiple sub anti-seepage membranes 120 can be connected by welding or other means. The overlapping size (width) of the welding between each sub anti-seepage membrane 120 can be greater than 30 cm, which can ensure the overall structural stability of the anti-seepage membrane 120 and improve the service life and reliability of the anti-seepage membrane 120. It can be understood that the surface of the foundation pit 110 includes the outer surface formed by the foundation pit 110, that is, the part of the foundation pit 110 located below the ground.

[0059] S300. Open a first hole 130 at the bottom of the anti-seepage membrane 120 and connect the first hole 130 to the drain pipe 160;

[0060] A first hole 130 is opened at the bottom of the anti-seepage membrane 120. The first hole 130 penetrates through the anti-seepage membrane 120, and the water in the accommodation space formed by the anti-seepage membrane 120 can enter and be discharged through the first hole 130. One end of the first hole 130 communicates with the accommodation space of the anti-seepage membrane 120, that is, the filling area of the native soil 100. When irrigating the crops on the native soil 100 or encountering heavy rainfall, the excess water in the native soil 100 can flow out through the first hole 130. The other end of the first hole 130 communicates with the drain pipe 160. The water flows out of the anti-seepage membrane 120 through the first hole 130 and then is discharged to the area to be drained through the drain pipe 160.

[0061] S400. Fill the native soil 100 into the accommodation space formed by the anti-seepage membrane 120.

[0062] Exemplarily, the native soil 100 can be filled into the accommodation space formed by the anti-seepage membrane 120, which is actually in the foundation pit 110. An anti-seepage membrane 120 is provided between the native soil 100 and the surface of the foundation pit 110. The foundation pit 110 is dug out from the saline-alkali land. The native soil 100 is arranged in the accommodation space formed by the anti-seepage membrane 120, and the salts in the saline-alkali land cannot penetrate into the interior of the native soil 100.

[0063] Please refer to Figures 1 to 3 , in this embodiment, determining the height of the native soil 100 and the slope of the inclined surface of the foundation pit 110 includes: determining that the height of the native soil 100 is not less than 0.5 m, and determining that the slope of the inclined surface of the foundation pit 110 is not greater than 60°.

[0064] The height of the native soil 100 is not less than 0.5 m, which can ensure the formation of a high-quality soil layer with sufficient thickness in the saline-alkali land. The sufficient thickness of the native soil 100 can provide sufficient growth space for the roots of the crops, enabling them to take root and absorb nutrients and water, thereby creating a relatively good soil environment for the growth of the crops, improving the survival rate and growth condition of the crops, and meeting the basic needs of crop planting.

[0065] The slope of the inclined surface of the foundation pit 110 is not greater than 60°, making the slope of the foundation pit 110 relatively gentle. Such a slope is beneficial to preventing unstable phenomena such as landslides and collapses of the slope soil under the action of gravity, ensuring the structural stability of the foundation pit 110 during the backfilling of the native soil 100 and subsequent use. The slope of the inclined surface of the foundation pit 110 is not greater than 60°, which is more convenient and safe for construction workers to carry out operations such as excavating the foundation pit 110, laying the anti-seepage membrane 120, and backfilling the native soil 100, reducing the construction difficulty and construction risk. For example, when laying the anti-seepage membrane 120, a gentler slope is convenient for construction workers to lay and fix, ensuring that the anti-seepage membrane 120 can be smoothly attached to the surface of the foundation pit 110 and improving the anti-seepage effect.

[0066] Please refer to Figures 1 to 3, in this embodiment, laying the anti-seepage membrane 120 on the surface of the foundation pit 110 includes: cleaning sundries such as sharp stones on the surface of the foundation pit 110; closely attaching the anti-seepage membrane 120 to the surface of the foundation pit 110; laying non-woven fabric vertically between the anti-seepage membrane 120 and the surface of the foundation pit 110 and above the anti-seepage membrane 120.

[0067] First, clean up sundries such as sharp stones on the surface of the foundation pit 110 that may affect the laying of the anti-seepage membrane 120, which can effectively prevent sharp objects from piercing the anti-seepage membrane 120 during construction or later use. Closely attach the anti-seepage membrane 120 to the surface of the foundation pit 110 to minimize the gap between the anti-seepage membrane 120 and the foundation pit 110, avoiding problems such as wrinkles and displacements of the anti-seepage membrane 120 caused by the filling soil 100 in the foundation pit 110 due to an overly large gap, ensuring that the anti-seepage membrane 120 can better bear the pressure of the filling soil 100 and ensuring the uniform stress of the anti-seepage membrane 120. Moreover, closely attaching the anti-seepage membrane 120 to the surface of the foundation pit 110 is conducive to the smooth flow of water along the surface of the anti-seepage membrane 120 to the first hole 130, achieving a good drainage effect.

[0068] Lay non-woven fabric vertically between the anti-seepage membrane 120 and the surface of the foundation pit 110 and above the anti-seepage membrane 120. On the one hand, the non-woven fabric is soft and can play a buffering and protective role between the anti-seepage membrane 120 and the surface of the foundation pit 110, and between the anti-seepage membrane 120 and the filling soil 100, preventing the anti-seepage membrane 120 from being scratched by sharp particles. On the other hand, the non-woven fabric has good water permeability and air permeability, does not hinder the passage of water, and can effectively prevent fine particles in the filling soil 100 from entering the drain pipe 160 and causing blockage, helping to drain excess water in a timely manner and avoiding waterlogging of the filling soil 100.

[0069] Please refer to Figures 1 to 3 , in this embodiment, closely attaching the anti-seepage membrane 120 to the surface of the foundation pit 110 includes: controlling the distance between the edge of the anti-seepage membrane 120 and the upper edge of the foundation pit 110 to be not less than 40 cm; digging a first annular groove 140 at a distance of 20 cm from the upper edge of the foundation pit 110, and the distance between the bottom surface of the first annular groove 140 and the surface of the saline-alkali land is not less than 20 cm; burying the saline-alkali soil dug out from the foundation pit 110 in the first annular groove 140 to press the anti-seepage membrane 120 and the bottom surface of the first annular groove 140.

[0070] The edge of the anti-seepage membrane 120 is the edge where the maximum outer diameter of the anti-seepage membrane 120 is located. Along the vertical direction, the upper edge of the foundation pit 110 is at one end of the foundation pit 110 away from the bottom of the foundation pit 110. The distance between the edge of the anti-seepage membrane 120 and the upper edge of the foundation pit 110 is not less than 40 cm. On the one hand, it can reserve space for fixing the anti-seepage membrane 120 subsequently. On the other hand, it can prevent the salt in the saline-alkali land from entering the imported soil 100 through the upper edge of the foundation pit 110 and salinizing the imported soil 100.

[0071] A first annular groove 140 is dug at a position not less than 20 cm away from the upper edge of the foundation pit 110. The first annular groove 140 surrounds the foundation pit 110. Then, the saline-alkali soil excavated from the foundation pit 110 is buried in the first annular groove 140, and then the anti-seepage membrane 120 is pressed against the bottom of the first annular groove 140 to make the two closely fit. In this way, the position of the anti-seepage membrane 120 can be fixed, effectively preventing the anti-seepage membrane 120 from moving or loosening due to external force pulling and soil movement, and ensuring that the anti-seepage membrane 120 is in a stable working state for a long time.

[0072] Please refer to Figures 1 to 3 , in this embodiment, laying the anti-seepage membrane 120 on the surface of the foundation pit 110 further includes: laying a 5-cm thick fine sand layer above the non-woven fabric to press the anti-seepage membrane 120 against the bottom of the foundation pit 110.

[0073] Exemplarily, after laying the non-woven fabric on the upper surface of the anti-seepage membrane 120, a 5-cm thick fine sand layer can be laid on the non-woven fabric on the upper surface of the anti-seepage membrane. On the one hand, the fine sand layer can press the anti-seepage membrane 120 against the bottom of the foundation pit 110 to make the anti-seepage membrane 120 fit more closely with the bottom of the foundation pit 110. On the other hand, the fine sand layer is located between the imported soil 100 and the anti-seepage membrane 120, which can prevent the sharp impurities in the imported soil 100 from piercing the anti-seepage membrane 120 and enhance the stability and reliability of the use of the anti-seepage membrane 120.

[0074] When the imported soil 100 undergoes dry-wet changes or minute displacements, the fine sand layer can buffer the minute displacements, reduce the pulling of the displacements on the anti-seepage membrane 120 and the non-woven fabric, extend the service life of the anti-seepage membrane 120, and ensure that the imported soil 100 in the saline-alkali land is not salinized for a long time.

[0075] In addition, the fine sand layer has good fluidity and can evenly cover the non-woven fabric and the anti-seepage membrane 120. The fine sand layer can apply uniform pressure to the anti-seepage membrane 120 to make the bottom of the foundation pit 110 closely fit with the anti-seepage membrane 120.

[0076] Please refer to Figures 1 to 3, in this embodiment, a first hole 130 is opened at the bottom of the anti-seepage membrane 120, and the first hole 130 is communicated with the drain pipe 160. Specifically: a first hole 130 is opened at the bottom of the anti-seepage membrane 120 to communicate the first hole 130 with the drain pipe 160; a filter cover 150 is provided at one end of the first hole 130 facing the anti-seepage membrane 120 to prevent impurities such as sediment from entering the drain pipe 160.

[0077] A first hole 130 is provided at the bottom of the anti-seepage membrane 120. The first hole 130 penetrates through both ends of the anti-seepage membrane 120 in the vertical direction. A filter cover 150 is provided at one end of the first hole 130 facing the anti-seepage membrane 120, which can effectively intercept impurities such as sediment and fine particles in the backfill soil 100 and prevent them from entering the drain pipe 160 to cause blockage, so as to maintain the smoothness of the drain pipe 160, enable the excess water in the backfill soil 100 to be discharged in time, and avoid the occurrence of water accumulation in the backfill soil 100.

[0078] Exemplarily, the filter cover 150 can be constructed by wrapping two layers of filter cloth.

[0079] Please refer to Figures 1 to 3 , in this embodiment, one end of the drain pipe 160 is communicated with the first hole 130, the other end of the drain pipe 160 is communicated with the drainage well 170, and the distance between the bottom of the drainage well 170 and the bottom surface of the foundation pit 110 is not less than 0.5 m.

[0080] The drain pipe 160 communicates the first hole 130 with the drainage well 170 to build a complete drainage channel, so that the accumulated water in the backfill soil 100 can be smoothly discharged. The distance between the bottom of the drainage well 170 and the bottom of the foundation pit 110 is not less than 0.5 m, which ensures that the drainage well 170 has enough depth to accommodate water and avoids the accumulated water flowing back into the foundation pit 110 due to the shallowness of the drainage well 170, ensuring that the excess water can be continuously and efficiently discharged and maintaining a good growth environment for crops.

[0081] Please refer to Figures 1 to 3 , in this embodiment, when the depth of the accumulated water in the drainage well 170 is higher than 1 / 4 of the height of the backfill soil 100, a water pump is used to pump out the accumulated water in the well.

[0082] When the depth of the accumulated water in the drainage well 170 is higher than 1 / 4 of the height of the filled soil 100, pump out the water in time to clean the accumulated water in the drainage well 170 in time, which is convenient for the accumulated water in the filled soil 100 to drain into the drainage well 170. According to the principle of communicating vessels, it can be understood that when the depth of the accumulated water in the drainage well 170 is 1 / 4 of the height of the filled soil 100, the height of the accumulated water in the drainage well 170 is flush with 1 / 4 of the height of the filled soil 100. At this time, pumping out the accumulated water in the drainage well 170 in time can prevent the filled soil 100 from being soaked by the accumulated water for a long time. Excessive accumulated water will make the soil in a too wet state, resulting in a decrease in the oxygen content in the soil. The roots of crops cannot breathe and absorb nutrients normally due to lack of oxygen, and even root rot may occur. Pumping water according to this standard can drain the excess accumulated water in time, create a good ventilation environment for the roots of crops, ensure the healthy growth of the roots of crops, and improve the survival rate and growth quality of crops.

[0083] Exemplarily, the pumped accumulated water can be stored or reasonably utilized according to the actual situation. For example, the pumped accumulated water can be used for irrigating vegetation, or the pumped accumulated water can be stored and used to irrigate crops when needed.

[0084] Please refer to Figures 1 to 3 , in this embodiment, the filled soil 100 is filled in the accommodation space formed by the anti-seepage membrane 120. Specifically: the filled soil 100 is filled in the accommodation space formed by the anti-seepage membrane 120, and the height of the filled soil 100 is controlled to be not less than 0.15 m higher than the height of the foundation pit 110; the upper surface of the filled soil 100 is controlled to be flat and parallel to the upper surface of the saline-alkali land.

[0085] The filled soil 100 is filled in the accommodation space formed by the anti-seepage membrane 120, and the filled soil 100 is spread over the accommodation space formed by the anti-seepage membrane 120. The height of the filled soil 100 is controlled to be not less than 0.15 m higher than the height of the foundation pit 110. This can prevent the loss of the filled soil 100 caused by factors such as weathering and rain erosion from washing away or blowing away the filled soil 100. Moreover, the higher height of the filled soil 100 is also beneficial to the full growth of the roots of crops.

[0086] Controlling the height of the filled soil 100 to be not less than 0.15 m higher than the height of the foundation pit 110, it can be understood that the height of the filled soil 100 protrudes above the height of the foundation pit 110. In this way, in the event of extreme weather such as heavy rain, rainwater will not accumulate in the foundation pit 110 due to the height of the filled soil 100 being lower than the height of the foundation pit 110, reducing the probability of crops and the like being submerged. In addition, controlling the upper surface of the filled soil 100 to be flat and parallel to the upper surface of the saline-alkali land can also reduce the probability of rainwater accumulating in the foundation pit 110 in the event of extreme weather such as heavy rain.

[0087] Please refer to Figures 1 to 3, ridges 101 are provided on the part of the imported soil 100 that is higher than the foundation pit 110 to drain rainwater from the imported soil 100 filling area.

[0088] The arrangement of the ridges 101 can guide the rainwater to flow in a specific direction, prevent waterlogging from forming in the imported soil 100 filling area, avoid the imported soil 100 from being soaked, which affects the air permeability of the soil and the growth environment of the roots. Long-term waterlogging may also cause the loss of nutrients in the imported soil 100 and even lead to soil compaction.

[0089] Providing ridges 101 on the part of the imported soil 100 that is higher than the foundation pit 110 to drain rainwater from the imported soil 100 filling area can keep the imported soil 100 in good condition, thereby ensuring the effective growth of crops.

[0090] Please refer to Figures 1 to 4 , Example 1. Exemplarily, in August 2024, a saline-alkali land was treated. The height H1 of the improved imported soil 100 was 1 m, the height H2 of the foundation pit 110 was 0.8 m, the slope α of the foundation pit 110 was 45°, the height H3 of the ridges 101 was 0.2 m, the depth H4 of the first annular ditch 140 was 0.3 m, the distance E1 between the first annular ditch 140 and the edge of the foundation pit 110 was 20 cm, and the distance E2 between the edge of the anti-seepage membrane 120 and the upper edge of the foundation pit 110 was 100 cm.

[0091] Table 1 shows the comparison of the conductivity and pH value of the imported soil 100 with the anti-seepage membrane 120 and the imported soil 100 without the anti-seepage membrane 120 at different depths in September 2024:

[0092]

[0093] Table 1

[0094] Table 2 shows the comparison of the conductivity and pH value of the imported soil 100 with the anti-seepage membrane 120 and the imported soil 100 without the anti-seepage membrane 120 at different depths within the range of 0 - 20 cm in the cross-section from October 2024 to February 2025:

[0095]

[0096] Table 2

[0097] Table 3 shows the comparison of the conductivity and pH value of the imported soil 100 with the anti-seepage membrane 120 and the imported soil 100 without the anti-seepage membrane 120 at different depths within the range of 0 - 20 cm in the cross-section from January 2025 to February 2025:

[0098]

[0099] Table 3

[0100] As can be seen from the results in the comparison table, an impermeable membrane 120 is provided between the imported soil 100 and the foundation pit 110, which can effectively prevent the imported soil 100 from being salinized and is beneficial to the long-term growth of crops in the imported soil 100.

[0101] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, commodity or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, commodity or device. Without further limitation, an element defined by the statement "comprising one..." does not exclude the presence of additional identical elements in the process, method, commodity or device comprising the said element.

[0102] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and the differences between each embodiment and other embodiments are emphasized. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the description of the method embodiment.

[0103] The above description is only for the embodiments of the present application and is not intended to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

[0104] Although the embodiments of the present application are described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A method for improving saline-alkali soil by using an anti-permeability membrane combined with imported soil backfill, characterized in that: include: Determine the height of the imported soil and the slope of the foundation pit, and dig the foundation pit in the saline-alkali land; Laying an anti-seepage membrane on the surface of the foundation pit; A first hole is opened at the bottom of the anti-permeability membrane, and the first hole is connected to a drainage pipe; The foreign soil is filled in the accommodation space formed by the anti-permeation membrane.

2. The soil improvement method according to claim 1, characterized in that: Determine the height of the imported soil and the slope of the foundation pit including: It is determined that the height of the imported soil is not less than 0.5m, and that the slope of the inclined surface of the foundation pit is not greater than 60°.

3. The soil improvement method according to claim 2, characterized in that: Laying an anti-seepage membrane on the surface of the foundation pit includes: Cleaning the surface of the foundation pit of sharp stones and other debris; The anti-permeability membrane is closely attached to the surface of the foundation pit; Nonwoven fabric is laid between the anti-seepage membrane and the surface of the foundation pit and above the anti-seepage membrane in the vertical direction.

4. The soil improvement method according to claim 3, characterized in that: The step of closely contacting the anti-permeability membrane with the surface of the foundation pit comprises: The distance between the edge of the anti-permeability membrane and the upper edge of the foundation pit is controlled to be no less than 40 cm; A first annular ditch is dug at a distance of 20 cm from the upper edge of the foundation pit, and the distance between the bottom surface of the first annular ditch and the surface of the saline-alkali land is not less than 20 cm; The saline-alkali soil excavated from the foundation pit in the saline-alkali land is buried in the first annular ditch to compact the anti-seepage membrane and the bottom surface of the first annular ditch.

5. The soil improvement method according to claim 3, characterized in that: Laying the anti-permeability membrane on the surface of the foundation pit also includes: laying a 5 cm layer of fine sand above the non-woven fabric to press the anti-permeability membrane and the bottom of the foundation pit.

6. The soil improvement method according to claim 3, characterized in that: A first hole is opened at the bottom of the anti-permeability membrane, and the first hole is connected to the drainage pipe, specifically: The first hole is opened at the bottom of the anti-seepage device, so that the first hole is connected to the drainage pipe; A filter cover is arranged at one end of the first hole facing the anti-permeability membrane to prevent impurities such as mud and sand from entering the drainage pipe.

7. The soil improvement method according to claim 6, characterized in that: One end of the drainage pipe is connected to the first hole, and the other end of the drainage pipe is connected to a drainage well. The distance between the bottom of the drainage well and the bottom surface of the foundation pit is not less than 0.5m.

8. The soil improvement method according to claim 7, characterized in that: When the depth of the accumulated water in the drainage well is higher than 1 / 4 of the height of the added soil, a water pump is used to pump out the accumulated water in the well.

9. The soil improvement method according to claim 1, characterized in that: The foreign soil is filled into the accommodation space formed by the anti-permeation membrane, specifically: Filling the imported soil in the accommodation space formed by the anti-permeability membrane, and controlling the height of the imported soil to be not less than 0.15m higher than the height of the foundation pit; The upper surface of the imported soil is controlled to be flat and parallel to the upper surface of the saline-alkali land.

10. The soil improvement method according to claim 9, characterized in that: A ridge is arranged at a portion where the imported soil is higher than the foundation pit so that rainwater can be discharged from the imported soil filling area.

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