Soil improvement method for coastal saline-alkali land

Abstract

The invention relates to the field of soil improvement, and particularly discloses a soil improvement method for coastal saline-alkali soil. According to the method, a physical method and a biological method are comprehensively utilized for comprehensive treatment of the saline-alkali soil, the large drainage ditch communicated with the surrounding river channel is dug for discharging salt into the river channel, the soil tank and the salt drainage ditch are dug, the plastic permeable blind pipe wrapped with the non-woven fabric is placed in the salt drainage ditch, the salt drainage ditch is backfilled with gravel, and the soil tank is backfilled with planting soil; organic compound fertilizer is evenly sown on the surface of the improved area, after long-time natural rainfall and manual watering, flowing water dissolves salt and alkaline substances in planting soil to form saline-alkaline water, and the saline-alkaline water flows into the plastic permeable blind pipe through the gravel layer and is finally discharged into the large drainage ditch to flow into the river channel. Salt and alkaline substances in the soil above the salt elimination ditch are effectively reduced, the wet soil promotes rapid decomposition of organic fertilizer and effective removal of salt, the improvement time of the saline-alkali soil is effectively shortened, and a good improvement effect can be maintained for a long time.

Description

Technical Field

[0001] The invention belongs to the technical field of soil improvement, and in particular relates to a soil improvement method for coastal saline-alkali land. Background Art

[0002] Saline-alkali land is usually not suitable for agricultural cultivation because it contains too much salt and alkaline substances in the soil. By improving saline-alkali land, the inhibitory effect of soil salinity on crop growth can be reduced, and it can be converted into arable land, thereby improving land productivity, and increasing crop yield and quality, thereby increasing the supply of food or other crops.

[0003] There are many methods for improving saline-alkali land, including physical, chemical and biological methods, but each has its own limitations. Physical methods include deep plowing, turning over the soil, drainage and other measures, aimed at improving soil structure and reducing salt accumulation. However, this method is only effective for shallow saline-alkali soil and has limited effect on deep saline-alkali soil improvement. Chemical methods adjust the pH and salt content of the soil by applying chemical improvers (such as gypsum, sodium sulfate, etc.). These methods can quickly reduce soil salinity, but long-term use may lead to the accumulation of certain elements in the soil and may even have a negative impact on the environment. Biological methods promote soil self-repair and ecological restoration by planting salt-tolerant plants, applying organic fertilizers or using microorganisms to improve soil biological properties. Although biological methods are more environmentally friendly, their effects are usually slow and it takes a long time to see obvious improvement effects.

[0004] It can be seen that saline soil improvement is a complex and long process. How to shorten the improvement time of saline-alkali land and maintain good improvement effects for a long time has become one of the goals that need to be explored in the current saline-alkali land improvement. Summary of the invention

[0005] In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide a soil improvement method for coastal saline-alkali land, so as to solve the problem that the existing saline-alkali land improvement methods take a long time to take effect and the improvement effect cannot be maintained for a long time.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A soil improvement method for coastal saline-alkali land, comprising:

[0008] Deeply ploughing and tilling the coastal saline-alkali land to be improved, and dividing the coastal saline-alkali land to be improved into a plurality of improvement areas;

[0009] Large drainage ditches connected to the surrounding river channels are dug around each of the improved areas, and small drainage ditches are dug longitudinally on each of the improved areas;

[0010] Compact the original soil in the middle of the improved area, dig a soil trench with a rectangular cross section in the longitudinal direction of the improved area, and then dig a salt drainage ditch with an inverted trapezoidal cross section at the bottom of the soil trench, wherein the salt drainage ditch is above the groundwater level;

[0011] Non-woven fabrics are laid at the bottom and sides of the salt drainage ditch as a soil barrier layer, and a plastic permeable blind pipe connected to the large drainage ditch and wrapped with non-woven fabrics is laid at the bottom of the salt drainage ditch;

[0012] Cover the plastic permeable blind pipe with crushed stones and fill the salt drainage ditch, lay non-woven fabric as a soil barrier at the boundary between the salt drainage ditch and the soil trough, and backfill the soil trough with planting soil;

[0013] The organic compound fertilizer is evenly spread on the surface of the improved area, the land is plowed twice to evenly mix the organic compound fertilizer and the soil, and the soil improvement of the coastal saline-alkali land is completed after natural precipitation and artificial watering.

[0014] Preferably, the length of the improved zone is 30 m and the width is 10 m.

[0015] Preferably, the large drainage ditch has a width of 1.2 m, a depth of 0.6 m, and a slope ratio of 1:1.0 to 1.8, and the small drainage ditch has a width of 0.2 m, and a depth of 0.2 m.

[0016] Preferably, the width of the earth trough is 0.8m and the depth is 0.8m, the upper width of the salt drainage ditch is 0.8m, the lower width is 0.4m and the depth is 0.3m, and the diameter of the plastic permeable blind pipe is 0.2m.

[0017] Preferably, the crushed stone particle size is 1-3 cm.

[0018] Preferably, the organic compound fertilizer comprises the following raw materials in parts by weight: 20 parts of decomposed sheep manure, 20 parts of decomposed cow manure, 20 parts of fungus residue and 3 parts of phosphate fertilizer.

[0019] Preferably, the secondary tillage method is vertical and horizontal deep tillage, the tillage times are 3-4 times, and the soil improvement depth is 30-40 cm.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The present invention comprehensively utilizes physical and biological methods to comprehensively manage saline-alkali land. First, deep ploughing and tillage are carried out to loosen the soil layer, and a large saline-alkali land is divided into multiple improved areas. A large drainage ditch connected to the surrounding river channel is excavated between the improved areas to discharge the salt in the improved areas into the river channel. A small drainage ditch for drainage is excavated on the improved areas. A soil trough and a salt drainage ditch are excavated in the middle of the improved areas. Non-woven fabrics are used to isolate the salt drainage ditch from the soil layer. A plastic permeable blind pipe wrapped with non-woven fabrics is placed inside the salt drainage ditch. The non-woven fabric can effectively prevent mud from entering the plastic permeable blind pipe. Gravel is backfilled inside the salt drainage ditch, and non-woven fabrics are laid again. The non-woven fabric can prevent mud from flowing into the gravel. layer, and finally backfill the planting soil inside the soil trough, and then evenly spread organic compound fertilizer on the surface of the improved area. After a long period of natural precipitation and artificial watering, the running water can dissolve the salt and alkaline substances in the planting soil to form saline-alkali water. The saline-alkali water flows through the gravel layer to the inside of the plastic permeable blind pipe, and finally discharged into the large drainage ditch and into the river. After a long period of flushing, the salt and alkaline substances in the soil above the drainage ditch can be effectively reduced. At the same time, the moist soil can promote the rapid decomposition of organic fertilizers and the effective removal of salt. The biological action of microorganisms can effectively shorten the improvement time of saline-alkali land, and can maintain a good improvement effect for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A block diagram of the improved method of the present invention;

[0023] Figure 2 It is a diagram of the improved area division of the present invention;

[0024] Figure 3 It is the structural diagram of the soil trough and salt drainage ditch of the present invention;

[0025] Figure 4 This is a schematic diagram of the structure of the plastic water-permeable blind pipe of the present invention;

[0026] In the figure: 1. Large drainage ditch; 2. Small drainage ditch; 3. Earth trough; 4. Salt drainage ditch; 5. Non-woven fabric; 6. Plastic permeable blind pipe. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example:

[0029] See also Figure 1 - Figure 4 As shown, a soil improvement method for coastal saline-alkali land comprises:

[0030] Deeply plough and till the coastal saline-alkali land to be improved, and divide the coastal saline-alkali land to be improved into multiple improvement areas, each of which is 30m long and 10m wide, so as to reduce the saline-alkali land from large to small, which is convenient for rectification of small improvement areas and also convenient for subsequent use of water flow to discharge the salt in the improvement areas;

[0031] A large drainage ditch 1 connected to the surrounding river channel is dug around each improved area, and a small drainage ditch 2 is dug longitudinally on each improved area. The large drainage ditch 1 has a width of 1.2m, a depth of 0.6m, and a slope ratio of 1:1.0-1.8. The small drainage ditch 2 has a width of 0.2m and a depth of 0.2m. The salt in each improved area can be discharged into the river channel through the large drainage ditch 1;

[0032] The original soil in the middle of the improved area is compacted, and a soil trough 3 with a rectangular cross section is excavated longitudinally in the improved area, and then a salt drainage ditch with an inverted trapezoidal cross section is excavated at the bottom of the soil trough 3. The width of the soil trough 3 is 0.8m, and the depth is 0.8m. The upper width of the salt drainage ditch 4 is 0.8m, the lower width is 0.4m, and the depth is 0.3m. In order to avoid the water level blocking the salt drainage ditch 4, resulting in the inability of the water with salt above the salt drainage ditch 4 to flow away in time, the salt drainage ditch 4 is above the groundwater level. Relative to the water level, the salt drainage ditch 4 is suspended, which is convenient for the water in the salt drainage ditch 4 to flow to a lower place;

[0033] A non-woven fabric 5 is laid at the bottom and side of the salt drainage ditch 4 as a soil barrier layer, and a plastic permeable blind pipe 6 connected to the large drainage ditch 1 and wrapped with the non-woven fabric 5 is laid at the bottom of the salt drainage ditch 4. The diameter of the plastic permeable blind pipe 6 is 0.2m, which is convenient for water with salt and alkaline substances from the outside to flow into the plastic permeable blind pipe 6 through the non-woven fabric 5;

[0034] Use gravel to cover the plastic permeable blind pipe 6 to fill the salt drainage ditch 4. The gravel particle size is 1-3 cm. There are gaps between the gravel to facilitate the flow of water. Lay non-woven fabric 5 as a soil barrier at the boundary between the salt drainage ditch 4 and the soil trough 3, and backfill the soil trough 3 with planting soil.

[0035] The organic compound fertilizer is evenly spread on the surface of the improved area, and the land is plowed twice to evenly mix the organic compound fertilizer and soil. The plowing times are 3-4 times, and the soil improvement depth is 30-40cm. The organic compound fertilizer includes the following raw materials in parts by weight: 20 parts of decomposed sheep manure, 20 parts of decomposed cow manure, 20 parts of fungus residue and 3 parts of phosphate fertilizer. After natural precipitation and artificial watering, the soil improvement of coastal saline-alkali land is completed.

[0036] As can be seen from the above, the comprehensive use of physical and biological methods for the comprehensive management of saline-alkali land is to firstly carry out deep ploughing and plowing of the saline-alkali land to make the soil layer loose, so as to facilitate the entry of water and air into the soil, and divide the large saline-alkali land into multiple improved areas. A large drainage ditch 1 connecting the surrounding rivers is dug between the improved areas to discharge the salt in the improved areas into the rivers, and a small drainage ditch 2 for drainage is dug on the improved areas. An earth trough 3 and a salt drainage ditch 4 are dug in the middle of the improved areas, and a non-woven fabric 5 is used to isolate the salt drainage ditch 4 from the soil layer. A plastic permeable blind pipe 6 wrapped with the non-woven fabric 5 is placed inside the salt drainage ditch 4. The non-woven fabric 5 can effectively prevent mud from entering the plastic permeable blind pipe 6, and gravel is backfilled inside the salt drainage ditch 4, and the non-woven fabric 5 is laid again. The non-woven fabric 5 can prevent mud from flowing into the gravel. The stone layer is finally filled with planting soil inside the soil trough 3, and then organic compound fertilizer is evenly spread on the surface of the improved area. Microorganisms can improve the biological properties of the soil and promote the self-repair and ecological restoration of the soil. After a long period of natural precipitation and artificial watering, the running water can dissolve the salt and alkaline substances in the planting soil to form saline water. The saline water flows through the gravel layer to the inside of the plastic permeable blind pipe 6, and is finally discharged into the large drainage ditch 1 and flows into the river. After a long period of flushing, the salt and alkaline substances in the soil above the salt drainage ditch 4 can be effectively reduced. At the same time, the moist soil can promote the rapid decomposition of organic fertilizers and the effective removal of salt. The biological action of microorganisms effectively shortens the improvement time of saline-alkali land, and can maintain a good improvement effect for a long time.

[0037] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0038] In the drawings of the embodiments disclosed in the present invention, only the structures related to the embodiments disclosed in the present invention are involved, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other.

Claims

1. A soil improvement method for coastal saline-alkali land, characterized in that: include: Deeply ploughing and tilling the coastal saline-alkali land to be improved, and dividing the coastal saline-alkali land to be improved into a plurality of improvement areas; Large drainage ditches connected to the surrounding river channels are dug around each of the improved areas, and small drainage ditches are dug longitudinally on each of the improved areas; Compact the original soil in the middle of the improved area, dig a soil trench with a rectangular cross section in the longitudinal direction of the improved area, and then dig a salt drainage ditch with an inverted trapezoidal cross section at the bottom of the soil trench, wherein the salt drainage ditch is above the groundwater level; Non-woven fabrics are laid at the bottom and sides of the salt drainage ditch as a soil barrier layer, and a plastic permeable blind pipe connected to the large drainage ditch and wrapped with non-woven fabrics is laid at the bottom of the salt drainage ditch; Cover the plastic permeable blind pipe with crushed stones and fill the salt drainage ditch, lay non-woven fabric as a soil barrier at the boundary between the salt drainage ditch and the soil trough, and backfill the soil trough with planting soil; The organic compound fertilizer is evenly spread on the surface of the improved area, the land is plowed twice to evenly mix the organic compound fertilizer and the soil, and the soil improvement of the coastal saline-alkali land is completed after natural precipitation and artificial watering.

2. The soil improvement method for coastal saline-alkali land according to claim 1, characterized in that: The length of the improved area is 30m and the width is 10m.

3. The soil improvement method for coastal saline-alkali land according to claim 1, characterized in that: The width of the large drainage ditch is 1.2m, the depth is 0.6m, and the slope ratio is 1:1.0-1.8; the width of the small drainage ditch is 0.2m, and the depth is 0.2m.

4. The soil improvement method for coastal saline-alkali land according to claim 1, characterized in that: The width of the earth trough is 0.8m, and the depth is 0.8m. The upper width of the salt drainage ditch is 0.8m, the lower width is 0.4m, and the depth is 0.3m. The diameter of the plastic permeable blind pipe is 0.2m.

5. The soil improvement method for coastal saline-alkali land according to claim 1, characterized in that: The crushed stone particle size is 1-3 cm.

6. The soil improvement method for coastal saline-alkali land according to claim 1, characterized in that: The organic compound fertilizer comprises the following raw materials in parts by weight: 20 parts of decomposed sheep manure, 20 parts of decomposed cow manure, 20 parts of fungus residue and 3 parts of phosphate fertilizer.

7. The soil improvement method for coastal saline-alkali land according to claim 1, characterized in that: The secondary tillage method is vertical and horizontal deep tillage, the tillage times are 3-4 times, and the soil improvement depth is 30-40cm.

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