Biological vertical shaft suitable for water and salt discharge of soda saline-alkali soil

Abstract

The invention provides a biological shaft suitable for drainage and salt elimination of soda saline-alkali soil, which comprises drainage blind ditches and a water-collecting well, the drainage blind ditches are arranged in the saline-alkali soil in a staggered manner, and the water-collecting well is arranged at the intersection of the drainage blind ditches; the upper part of the water-collecting well is filled with a fine sand layer, the lower part of the water-collecting well is filled with a biological material layer, and the depth ratio of the fine sand layer to the biological material layer is 1: 1; the biological material layer comprises straw and kieselguhr, the volume ratio of the straw to the kieselguhr is 3: 1, the straw is in an unsmashed undisturbed plant form, the straw is vertically arranged in the water collecting well, and the effects that the construction cost is reduced, and the water and salt discharging effect is improved are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of saline-alkali land improvement, and in particular to a biological vertical well suitable for draining water and salt from soda saline-alkali soil. Background Art

[0002] The improvement of saline-alkali land, especially soda saline-alkali soil, is of great significance to agricultural production and ecological environment protection. Soda saline-alkali soil has poor water permeability. After heavy rainfall or irrigation, water easily accumulates on the surface, which seriously affects land utilization and crop growth.

[0003] In the related technology, vertical shaft filling with sand and salt removal is a common method, which is to set up a vertical shaft in the saline-alkali land and fill it with sand and gravel, so that irrigation water and precipitation can vertically infiltrate into the fine sand interlayer, which plays the role of leaching salt and drainage.

[0004] Regarding the above-mentioned related technologies, since this method has a large construction range and a deep vertical shaft, it is easy to damage the fragile soil structure of soda saline-alkali soil, and the maintenance and management of the vertical shaft is relatively complicated, there are problems such as complex construction, high cost, and poor drainage and salt removal effect. Summary of the invention

[0005] The purpose of the present invention is to provide a biological vertical shaft suitable for draining and desalting soda saline-alkali soil, so as to solve the problems of complex vertical shaft construction, high cost and poor drainage and desalting effect.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme for a biological vertical well suitable for drainage and salt removal of soda saline-alkali soil:

[0007] A biological vertical shaft suitable for draining water and salt from soda saline-alkali soil, comprising a drainage culvert and a water collection well, wherein the drainage culverts are arranged in an interlaced manner in the saline-alkali soil, and the water collection well is arranged at the intersection of the drainage culverts; the upper part of the water collection well is filled with a fine sand layer, and the lower part of the water collection well is filled with a biological material layer, and the ratio of the depth of the fine sand layer to the depth of the biological material layer is 1:1; the biological material layer comprises straw and diatomaceous earth, and the volume ratio of the straw to the diatomaceous earth is 3:1, the straw is in an original plant form that is not crushed, and the straw is vertically arranged in the water collection well.

[0008] As an optimization of a biological vertical well suitable for draining water and salt from soda saline-alkali soil, a ground covering layer is arranged on the top of the water collection well, and the ground covering layer is original soil, and the ground covering layer is raised from the ground surface by at least 10 cm.

[0009] As an optimization of a biological vertical shaft suitable for draining water and salt from soda saline-alkali soil, the type of straw includes at least one of corn straw and sunflower straw.

[0010] As an optimization of a biological vertical well suitable for drainage and salt removal of soda saline-alkali soil, the diameter of the water collection well is 30-50 cm, and the depth of the biological material layer is at least 0.8 m.

[0011] As an optimization of a biological vertical shaft suitable for drainage and salt removal of soda saline-alkali soil, in a section of the drainage ditch between two adjacent water collection wells, the midpoint of the drainage ditch bulges upward, and a ramp is provided extending from the midpoint of the drainage ditch to both ends of the drainage ditch, and the slope of the ramp is set to 1%-3%.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] (1) The vertical stacking of uncomminuted straw in the biological shaft forms a continuous pore channel, which, combined with the adsorption and stabilization effect of diatomaceous earth, significantly accelerates the vertical infiltration of water and the efficiency of salt leaching, effectively solving the problem of poor water permeability and surface water accumulation in soda saline-alkali soil. The synergistic effect of straw and diatomaceous earth delays cellulose degradation, maintains the long-term stability of vertical waterways, avoids pore collapse, ensures that salt is continuously leached into deep soil or groundwater, and inhibits salt surface accumulation.

[0014] (2) The use of easily accessible, low-cost biomaterials such as crop straw, diatomaceous earth and fine sand significantly reduces material costs. The standardized design of the water collection well diameter (30-50 cm) and layer depth (80 cm for each fine sand layer and straw layer) simplifies the construction process and reduces the need for mechanical operations.

[0015] (3) The ground cover layer inhibits evaporation and salt return, reduces capillary rise of salt, and protects the filling layer from physical erosion, thereby extending the service life of the system.

[0016] (4) The raised midpoint and ramp design of the drainage ditch improves the efficiency of water gravity flow and reduces the frequency of manual maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0018] Figure 1 This is a schematic diagram of the construction layout of the biological shaft in the embodiment of the present application;

[0019] Figure 2 This is a cross-sectional view of the biological shaft according to an embodiment of the present application.

[0020] In the figure: 1. Drainage ditch; 2. Collection well; 3. Fine sand layer; 4. Biomaterial layer; 5. Ground cover layer. DETAILED DESCRIPTION

[0021] To make the technical solutions and advantages of the present invention more clear, the present invention and its beneficial effects will be described in further detail below in conjunction with specific implementation methods and accompanying drawings, but the implementation methods of the present invention are not limited thereto.

[0022] The standard parts used in the present invention can all be purchased from the market, and special-shaped parts can be customized according to the instructions and the drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, etc. in the prior art. Machinery, parts and equipment all adopt conventional models in the prior art, and the circuit connection adopts the conventional connection method in the prior art, which will not be described in detail here.

[0023] The following is combined with Figure 1-2 , further details of this application are given.

[0024] In soil science and agricultural science, soda saline-alkali soil refers to soil containing a large amount of soluble salts (such as sodium carbonate, etc.). These salts make the soil highly alkaline with a high pH value, which affects plant growth. The alkaline spot area refers to the area where salinization is particularly serious in saline-alkali soil, which usually appears as white salt frost or patches on the surface. Plants find it difficult to grow, forming bare or sparsely vegetated plots. In the alkaline spot area of ​​soda saline-alkali soil, the land is particularly salinized and it is difficult for plants to survive.

[0025] The present application provides a biological vertical well suitable for drainage and salt removal of soda saline-alkali soil, which adopts the following technical solution:

[0026] Reference Figure 1 and Figure 2 The biological vertical shaft includes a drainage ditch 1 and a water collection well 2. On the soda saline-alkali land, multiple drainage ditches 1 are intertwined with each other, and the minimum angle between the multiple drainage ditches 1 is greater than 0° and less than or equal to 90°. In the embodiment of the present application, the multiple drainage ditches 1 are perpendicular to each other and crisscrossed on the soda saline-alkali land, dividing the soda saline-alkali soil alkaline spot area into multiple rectangles or squares. The water collection well 2 is located at the intersection of multiple drainage ditches 1. When encountering heavy rainfall or irrigation, the surface water dissolves the soluble salts on the surface of the saline-alkali soil, and the surface water flows into the water collection well 2 through the drainage ditch 1.

[0027] Reference Figure 2, the upper part of the water collection well 2 is filled with a fine sand layer 3, and the lower part is filled with a biomaterial layer 4, and the depth of the fine sand layer 3 is 1:1 with the depth of the biomaterial layer 4. In actual construction applications, the fine sand layer 3 generally uses bright sand. Since the particles of the fine sand layer 3 are small and there are gaps between the particles, there are multi-directionally extending hydrophobic channels inside the fine sand layer 3; the surface water flowing into the water collection well 2 can be initially filtered through the fine sand layer 3, the attached soil gravel can be intercepted, and at the same time, the water flow is guided to penetrate downward. The biomaterial layer 4 includes straw and diatomaceous earth, and the volume of straw and diatomaceous earth is 3:1. Furthermore, the types of straw include corn straw, sunflower straw, wheat straw, rice straw, etc. In actual applications, the straw is usually one of corn straw and sunflower straw. The straw uses the original plant form without crushing, and the straw is placed vertically in the water collection well 2. Since the straw has a naturally porous and fibrous structure, it can form a continuous pore channel. When the straw is stacked vertically in its original state, the gaps between the fibers form a continuous vertical pore network, constructing a vertical waterway, which provides a direct path for water infiltration. At the same time, due to the low resistance of the vertical pore network of the straw, water can quickly penetrate downward, accelerating the vertical migration of water and the process of salt leaching, while avoiding the problem of surface water accumulation. At the same time, diatomaceous earth is mixed into the straw. On the one hand, the gaps between the straws are filled with diatomaceous earth to improve the stability of the vertical placement of the straw. On the other hand, the aluminosilicate component of diatomaceous earth fixes the extracellular enzymes secreted by the straw-decomposing bacteria through adsorption, slowing down the degradation of cellulose. This process not only maintains the long-term stability of the straw structure, but also prevents the pores from collapsing due to the rapid decay of the straw, ensuring the durability of the vertical waterway.

[0028] Through the biological vertical shaft constructed as above, the soluble salts on the surface of saline-alkali soil are dissolved in rainfall or irrigation, and flow into the water collection well 2 through the drainage culvert 1. The soil gravel is first initially filtered through the fine sand layer 3 and penetrates downward, and then the fiber structure inside the straw accelerates the vertical displacement of water, which goes directly to the deep soil or groundwater, avoiding surface water accumulation and salt re-accumulation on the surface. Compared with related technologies, it is not only simple in structure and low in construction cost, but also has smooth drainage and salt removal effects. After long-term use, the straw slowly decomposes under the action of microorganisms, releasing organic matter and forming humus. These organic substances can improve the soil aggregate structure, enhance the soil's ability to retain water and fertilizer, and provide nutrients for salt-tolerant plants, further consolidating the improvement effect of saline-alkali land.

[0029] In the preferred embodiment of the present application, refer to Figure 2, the top of the water collection well 2 is also filled with an above-ground covering layer 5, which is original soil and is 10 cm above the ground. The soil structure of saline-alkali land is fragile, and the surface settlement is easily caused by water infiltration after irrigation or rainfall. Covering the original soil and raising the surface by 10 cm, by dispersing the pressure and forming a buffer zone with the filling layer, can reduce direct impact, avoid deformation of the shaft structure due to uneven settlement, and keep the surface flat to prevent local collapse. At the same time, the covering layer isolates direct sunlight, wind erosion and rain scouring, delays the physical degradation of the fine sand layer 3 and the biomaterial layer 4, and ensures the long-term effectiveness of the vertical waterway. In addition, the covering layer reduces the evaporation rate of surface water, prevents saline water from rising to the surface through capillary action, and thus inhibits the re-accumulation of salt on the soil surface.

[0030] In a preferred embodiment of the present application, the diameter of the water collection well 2 is 30-50cm, and the depth of the biomaterial layer 4 is at least 0.8m. Taking into account the material properties, functional requirements and engineering practice, in the embodiment of the present application, the diameter of the water collection well 2 is 40cm, the depth of the biomaterial layer 4 is 0.8m, and the depth of the fine sand layer 3 is 0.8m. In practical applications, the water collection well 2 with a diameter range of 30-50cm is simple to construct and has low construction costs. The depth of the biomaterial layer 4 is at least 0.8m, and the uncrushed straw is stacked vertically in its original state. The depth of 80cm ensures the formation of a continuous vertical pore network, maintains the physical path for rapid water infiltration, and avoids the phenomenon of poor water drainage due to insufficient depth. The fine sand layer 3 has the same depth as the biomaterial layer 4, and the pressure distribution of the upper and lower layers is uniform, which reduces the shear stress caused by the depth difference and reduces the risk of landslides. In the pilot project in the soda saline-alkali soil area, the 0.8m fine sand layer 3 can intercept more than 90% of suspended particles (particle size > 0.1mm), and the infiltration rate of the biomaterial layer 4 at a depth of 0.8m can reach 2-3 times that of the traditional sand-filled shaft. The drainage efficiency during the flood season is improved by 40%, and no obvious landslides or blockages have occurred within 3 years, verifying its long-term stability.

[0031] In the preferred embodiment of the present application, refer to Figure 2 In a section of the drainage ditch 1 between two adjacent water collection wells 2, the midpoint of the drainage ditch 1 bulges upward, and a ramp is provided from the midpoint of the drainage ditch 1 to both ends of the drainage ditch 1, and the slope of the ramp is set to 1%-3%. By tilting the drainage ditch 1 to both sides with a certain slope, the accumulated water in the drainage ditch 1 can be accelerated to gather to the water collection wells 2 on both sides, forming a self-flow of accumulated water, and reducing the frequency of manual maintenance.

[0032] According to the disclosure and teaching of the above description, those skilled in the art to which the present invention belongs can also change and modify the above embodiment. Therefore, the present invention is not limited to the above specific embodiment, and any obvious improvement, replacement or modification made by those skilled in the art on the basis of the present invention belongs to the protection scope of the present invention. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation to the present invention.

Claims

1. A biological vertical shaft suitable for draining water and salt from soda saline-alkali soil, characterized in that: The invention comprises a drainage culvert (1) and a water collection well (2), wherein the drainage culverts (1) are arranged in a staggered manner in saline-alkali soil, and the water collection well (2) is arranged at the intersection of the drainage culverts (1); the upper part of the water collection well (2) is filled with a fine sand layer (3), and the lower part of the water collection well (2) is filled with a biological material layer (4), and the depth of the fine sand layer (3) and the depth of the biological material layer (4) are in a ratio of 1:1; the biological material layer (4) comprises straw and diatomaceous earth, and the volume ratio of the straw to the diatomaceous earth is 3:1, the straw is in an original plant form without being crushed, and the straw is vertically arranged in the water collection well (2).

2. A biological vertical shaft suitable for drainage and salt removal of soda saline-alkali soil according to claim 1, characterized in that: A ground covering layer (5) is arranged on the top of the water collection well (2); the ground covering layer (5) is original soil, and the ground covering layer (5) is raised above the ground surface by at least 10 cm.

3. A biological vertical shaft suitable for drainage and salt removal of soda saline-alkali soil according to claim 1, characterized in that: The straw includes at least one of corn straw and sunflower straw.

4. A biological vertical shaft suitable for draining water and salt from soda saline-alkali soil according to claim 1, characterized in that: The diameter of the water collection well (2) is 30-50 cm, and the depth of the biological material layer (4) is at least 0.8 m.

5. A biological vertical shaft suitable for draining water and salt from soda saline-alkali soil according to claim 1, characterized in that: In a section of the drainage ditch (1) between two adjacent water collection wells (2), the midpoint of the drainage ditch (1) bulges upward, and a ramp is provided extending from the midpoint of the drainage ditch (1) to both ends of the drainage ditch (1), and the slope of the ramp is set to 1%-3%.

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