Water and soil loss three-dimensional comprehensive prevention and control method for large waste slag field

Abstract

The invention provides a water and soil loss three-dimensional comprehensive prevention and control method for a large waste slag yard, which comprises the following steps: S1, slope toe blocking and protection: forming a retaining wall by combining artificial synthetic materials with sandy soil filling; s2, constructing a platform interception and drainage ditch, wherein the design of the drainage ditch determines the size, depth and gradient of a ditch body according to the catchment area, rainfall intensity and soil permeability factors of a side slope; s3, reconstructing a soil matrix; s4, constructing a vegetation layer; s5, configuring a multi-species plant community; s6, planting and maintenance management; s7, constructing a comprehensive prevention and control system; and S8, effect monitoring and evaluation: monitoring and evaluating the effect of the prevention and control system regularly. By optimizing engineering-plant comprehensive prevention and control measures, the synergistic effect of biology and engineering is enhanced, water and soil loss is restrained in a multi-level and all-around mode, and finally ecological treatment and vegetation recovery of the side slope are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of ecological environment protection technology, and in particular to a three-dimensional comprehensive prevention and control method for soil and water loss in a large-scale waste dump. Background Art

[0002] During the construction of railway projects in mountainous areas, a large amount of waste earth and stone will be piled up to form a slag dump. The area and amount of slag in the slag dump are relatively large. The accumulation and landfill of a large amount of engineering slag will inevitably cause damage to the native vegetation. Since the slopes of the slag dump are exposed and loose, it is very easy to cause soil erosion under the influence of rainfall, which will in turn cause secondary disasters such as mudslides and landslides, which not only damage the ecological environment, but also pose a threat to the production and life safety of the people.

[0003] At present, there are the following problems in the prevention and control of soil erosion on the slopes of waste dumps: First, traditional soil erosion control on the slopes of waste dumps mostly adopts single engineering measures (such as intercepting drainage ditches, retaining walls, etc.) or vegetation measures (such as planting vines, sowing grass seeds, etc.), which have problems such as large engineering workload, high cost and poor effect; Second, although a single engineering measure can temporarily stabilize the slope, it lacks vegetation protection, has poor erosion resistance, and is not conducive to ecological restoration; and vegetation measures are limited by site conditions, the slope is steep, the substrate is poor, it is difficult for plants to survive, the coverage rate is low, and the maintenance cost is very high. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a three-dimensional comprehensive prevention and control method for soil erosion in large-scale waste dumps, which optimizes the engineering-plant comprehensive prevention and control measures, strengthens the synergistic effect of biology and engineering, curbs soil erosion at multiple levels and in all directions, and ultimately achieves ecological management of the slope and vegetation restoration.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] A three-dimensional comprehensive prevention and control method for soil and water loss in a large-scale waste dump comprises the following steps:

[0007] S1. Slope foot protection: a retaining wall is formed by combining artificial synthetic materials with sand and soil filling. Drain holes are set at the bottom of the retaining wall to drain water behind the wall;

[0008] S2. Construct a platform intercepting drainage ditch. The design of the drainage ditch shall determine the size, depth and slope of the ditch according to the catchment area of ​​the slope, rainfall intensity and soil permeability factors;

[0009] S3. Reconstruction of soil matrix

[0010] S3.1. The bottom stabilization layer uses crushed stone with a particle size of 20-40 mm as the stabilization layer material, which is mechanically compacted by an excavator and a roller, with a compaction degree of not less than 90%;

[0011] S3.2, middle maturation layer, laying the waste residue maturation bacteria agent composite material on the stabilization layer as the maturation layer;

[0012] S3.3, surface vegetation layer, a vegetation layer is constructed on top of the mature layer, using humus soil and soil-fixing, water-retaining, crusting and anti-corrosion materials mixed in a ratio of 4:1;

[0013] S4. Constructing the vegetation layer

[0014] S4.1, material selection, composite materials with high-producing strains of extracellular polymers (EPS) as the core;

[0015] S4.2. Construction: Before constructing the vegetation layer, the mature layer should be leveled to ensure that there are no large particles or depressions on the surface.

[0016] S5. Multi-species plant community configuration

[0017] S5.1. Selection of native plants: Conduct detailed investigations on the climate and soil conditions of different ecological types and select suitable native plant species;

[0018] S5.2. Diversity configuration: the ratio of trees, shrubs and herbaceous plants should be controlled at 1:3:6;

[0019] S6. Planting and maintenance management

[0020] S6.1. Planting technology: choose the time and method of planting according to the growth characteristics of plants and seasonal changes;

[0021] S6.2. Maintenance and management: irrigate 2-3 times a month to ensure the water required for normal growth of plants;

[0022] S7. Build a comprehensive prevention and control system;

[0023] S8. Effectiveness monitoring and evaluation: Regularly monitor and evaluate the effectiveness of the prevention and control system.

[0024] In step S1, the synthetic material includes geogrid and geotextile.

[0025] In step S2, the drainage ditch is provided with a connecting pipe or a drop well to ensure smooth drainage.

[0026] In step S3.2, the maturation layer is formed by mixing high-efficiency phosphate-solubilizing, potassium-solubilizing and nitrogen-fixing microbial strains with organic fertilizers and water-retaining agents, and the thickness of the maturation layer is 25 cm.

[0027] In step S3.3, the thickness of the vegetation layer is 12 cm, and it is evenly sprayed on the surface of the maturation layer by a sprayer.

[0028] In step S5.1, the native plant species include spruce, willow, sweet clover, Elymus ovata, Potentilla fruticosa and Spiraea odorifera.

[0029] In step S7, the construction of a comprehensive prevention and control system includes three-dimensional comprehensive prevention and control and optimization and adjustment;

[0030] The three-dimensional integrated prevention and control is to organically combine the technical means of slope foot protection, platform interception and drainage, slope matrix layer reconstruction and multi-species plant community configuration;

[0031] The optimization and adjustment is to optimize and adjust the comprehensive prevention and control system according to the actual situation of the slope and the monitoring results.

[0032] The beneficial effects of the present invention are:

[0033] 1. Through the combination of source prevention and process control, engineering measures and overall vegetation protection, it can effectively curb soil and water loss on the slopes of large-scale waste dumps, improve vegetation coverage and survival rate, and enhance the anti-interference ability of waste dump slopes. It is of great significance to promote the construction of ecological civilization in railway projects and promote the ecological restoration of temporary land. At the same time, it provides new ideas and methods for the ecological management of waste dumps of the same type of projects, and has a strong demonstration effect and promotion value for guiding soil and water conservation and ecological restoration of open-pit mine slopes and tailings ponds.

[0034] 2. By constructing a shrub transplantation belt on the slope of the slag dump, a better soil and water conservation belt is formed, which can reduce soil and water loss to a greater extent.

[0035] 3. By constructing a multi-species community configuration model with native plants that adapt to the local climate and soil environment, we not only prevent the risk of invasion of alien species, but also increase the coverage of native plants on the slag dump to more than 70%, making the vegetation more stable and sustainable.

[0036] 4. The main materials used are all from the natural distribution areas of native plants. No auxiliary materials and biochemical reagents are used. The materials are easy to collect, with low cost and good benefits, and do not cause environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 The figure is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0038] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0039] Example 1

[0040] like Figure 1 As shown, a three-dimensional comprehensive prevention and control method for soil erosion in a large-scale waste dump includes the following steps:

[0041] S1. Slope foot protection: a retaining wall is formed by combining artificial synthetic materials with sand or gravel. Drain holes are set at the bottom of the retaining wall to drain water behind the wall.

[0042] According to the geological conditions and stability requirements of the slope, select suitable retaining wall materials, such as concrete, mortar masonry, reinforced soil, etc. For soil slopes, geosynthetics (such as geogrids, geotextiles) can be used in combination with sand or gravel to form retaining walls. The design of retaining walls needs to consider the stability, anti-slip and anti-overturning capabilities of the wall, and the size, burial depth and inclination angle of the wall are determined by calculation. Drain holes should be set at the bottom of the wall to drain water behind the wall. The retaining wall is constructed by layered pouring or masonry to ensure that each layer is firmly bonded. After the wall construction is completed, necessary maintenance is carried out to achieve the design strength.

[0043] S2. Construct a platform intercepting drainage ditch. The design of the drainage ditch shall determine the size, depth and slope of the ditch according to the catchment area of ​​the slope, rainfall intensity and soil permeability factors;

[0044] The design of drainage ditches needs to determine the size, depth and slope of the ditch body according to factors such as the catchment area of ​​the slope, rainfall intensity and soil permeability. The bottom and both sides of the ditch body should be treated with anti-seepage materials (such as concrete, geomembrane); drainage ditches should be set up on different height platforms of the slope to form a complete drainage network. Connecting pipes or drop wells should be set between drainage ditches to ensure smooth drainage. At the same time, the drainage ditch should be connected to the surrounding natural water system or artificial drainage facilities to guide the collected rainwater to a safe area. Regularly dredge and maintain the drainage ditch to prevent the silt in the ditch from affecting the drainage effect; at the same time, check the integrity of the drainage system and repair damaged parts in time.

[0045] S3. Reconstruction of soil matrix

[0046] S3.1. The bottom stabilization layer uses crushed stone with a particle size of 20-40mm as the stabilization layer material, which is mechanically compacted by excavators and rollers, with a compaction degree of not less than 90%; the thickness of the stabilization layer is determined according to the slope height. Generally, the thickness of the stabilization layer increases by 10cm for every 10m increase in slope height.

[0047] S3.2, middle maturation layer, on the stabilization layer, a composite material of waste residue maturation agent is laid as the maturation layer; the material is a mixture of efficient phosphorus-solubilizing, potassium-solubilizing and nitrogen-fixing microbial strains, organic fertilizers, water retaining agents, etc. The thickness of the maturation layer is set to 25cm, and it is evenly covered by mechanical paving and manual leveling. During the maturation process, water regularly to keep it moist to promote microbial activity and nutrient release.

[0048] S3.3, Surface vegetation layer, construct the vegetation layer on the mature layer, using humus soil and soil-fixing, water-retaining, crusting and anti-corrosion materials mixed in a ratio of 4:1; the thickness of the vegetation layer is set to 12cm, and it is evenly sprayed on the surface of the mature layer by a sprayer. After spraying, rake it lightly with a rake to fully mix the soil particles with the crusting material.

[0049] S4. Constructing the vegetation layer

[0050] S4.1, material selection, composite materials with high-producing strains of extracellular polymers (EPS) as the core;

[0051] The soil-fixing, water-retaining and anti-corrosion crust material uses a composite material with a high-yield strain of extracellular polymers (EPS) as the core; this material has good water retention and corrosion resistance, and can effectively enhance the stability of the soil. At the same time, an appropriate amount of water-retaining agent and fertilizer are added to the material to provide the necessary nutrients and water for plant growth.

[0052] S4.2. Construction: Before constructing the vegetation layer, the mature layer should be leveled to ensure that there are no large particles or depressions on the surface;

[0053] Before constructing the vegetation layer, the mature layer is leveled to ensure that there are no large particles and depressions on the surface; after the vegetation layer materials are evenly mixed, they are sprayed by a sprayer; during the spraying process, the spraying speed and angle are controlled to ensure that the materials are evenly covered on the surface of the mature layer. After spraying, use a rake to gently rake the surface to fully mix the soil particles with the crusting material; finally, carry out necessary compaction and maintenance to make the vegetation layer tightly combined with the underlying soil.

[0054] S5. Multi-species plant community configuration

[0055] S5.1. Selection of native plants: Conduct a detailed investigation of the climate and soil conditions of different ecological types along the route, and select suitable native plant species, such as spruce and alpine willow in subalpine cold and wet forests; sweet clover and lycopodium in dry valley shrubs and grasslands; and sweet clover and spirea in plateau alpine meadows. These plants have good adaptability, stress resistance and ecological benefits;

[0056] S5.2. Diversity allocation: the ratio of trees, shrubs and herbaceous plants should be controlled at 1:3:6 to ensure vegetation coverage and species diversity; at the same time, the ornamental value and economic benefits of plants should be considered for reasonable matching, such as planting some economic trees and medicinal plants;

[0057] S5.3, community structure configuration;

[0058] ① Multi-level configuration: A multi-level configuration mode combining trees, shrubs and herbaceous plants is adopted. Trees are used as the upper canopy layer to provide shade and ecological framework; shrubs are used as the middle layer vegetation to increase the coverage and stability of the slope; herbaceous plants are used as the lower ground cover layer to prevent soil erosion and provide nutrients; appropriate spacing and overlap are maintained between each layer to promote the interaction between plants and the stable development of the ecosystem.

[0059] ②Multi-structure configuration: Different structural configuration modes are adopted according to the slope and stability requirements of the slope. For slopes with gentle slopes (less than 30°), horizontal strip planting mode is adopted; for slopes with steep slopes (30°-60°), fish scale pits or stepped planting mode are adopted; for extremely steep slopes (greater than 60°), suspended green nets combined with spraying and grass planting are used for greening; at the same time, reinforced vegetation belts or biological slope protection engineering measures are set up at key parts of the slope (such as the foot of the slope and the turning point) to improve the overall stability of the slope.

[0060] S6. Planting and maintenance management

[0061] S6.1. Planting technology. Choose the planting time and method according to the growth characteristics and seasonal changes of the plants. For trees and shrubs, transplanting is used for planting. Necessary pruning and root treatment are performed before transplanting. The soil ball should be kept intact and watered appropriately during transplanting. After transplanting, a support is set up for fixing and support. For herbaceous plants, direct seeding or spray seeding is used for planting. Soil treatment and fertilization measures are carried out before sowing. After sowing, the soil should be kept moist until the seedlings emerge.

[0062] S6.2. Maintenance and management: irrigate 2-3 times a month to ensure the water required for normal growth of plants; irrigation should be arranged reasonably according to the needs of plants and climatic conditions, generally irrigate 2-3 times a month to ensure the water required for normal growth of plants. Fertilization: choose the type and amount of fertilizer suitable for plant growth, generally fertilize twice a year, in spring and autumn respectively. Weeding: remove weeds in time to reduce the competitive pressure on target plants; pest control: use a combination of biological control and chemical control to effectively control and ensure the healthy growth of plants.

[0063] S7. Build a comprehensive prevention and control system;

[0064] S8. Effect monitoring and evaluation: Regularly monitor and evaluate the effect of the prevention and control system;

[0065] Monitor and evaluate the effectiveness of the prevention and control system regularly; monitoring indicators include soil erosion, vegetation coverage, species diversity, etc. The amount of soil erosion is measured by setting up monitoring points and collecting lost soil samples; vegetation coverage is estimated by combining remote sensing image interpretation and field investigation; species diversity is determined by sample plot investigation and species identification. The prevention and control effect is evaluated by combining quantitative and qualitative methods based on monitoring data; for example, the effect of slope foot protection and platform drainage is evaluated by calculating the reduction rate of soil erosion; the effect of slope matrix reconstruction and multi-species plant community configuration is evaluated by measuring vegetation coverage and species diversity. At the same time, the overall effect of the prevention and control system is comprehensively evaluated in combination with expert evaluation and public opinion, and the prevention and control measures are adjusted in a timely manner according to the evaluation results to ensure that the prevention and control effect reaches the expected goal.

[0066] In step S1, the synthetic material includes geogrid and geotextile.

[0067] In step S2, the drainage ditch is provided with a connecting pipe or a drop well to ensure smooth drainage.

[0068] In step S3.2, the maturation layer is formed by mixing high-efficiency phosphate-solubilizing, potassium-solubilizing and nitrogen-fixing microbial strains with organic fertilizers and water-retaining agents, and the thickness of the maturation layer is 25 cm.

[0069] In step S3.3, the thickness of the vegetation layer is 12 cm, and it is evenly sprayed on the surface of the maturation layer by a sprayer.

[0070] In step S5.1, the native plant species include spruce, willow, sweet clover, Elymus ovata, Potentilla fruticosa and Spiraea odorifera.

[0071] In step S7, the construction of a comprehensive prevention and control system includes three-dimensional comprehensive prevention and control and optimization and adjustment;

[0072] The three-dimensional integrated prevention and control is to organically combine the technical means of slope foot protection, platform interception and drainage, slope matrix layer reconstruction and multi-species plant community configuration; each technical link coordinates and complements each other to maximize the prevention and control effect. For example, slope foot protection and platform interception and drainage can effectively reduce the scouring and erosion of rainwater on the slope; slope matrix layer reconstruction provides a stable matrix environment for plant growth; multi-species plant community configuration improves the ecological stability and self-repair ability of the slope by increasing vegetation coverage and species diversity.

[0073] The optimization and adjustment mentioned above is to optimize and adjust the comprehensive prevention and control system according to the actual situation of the slope and the monitoring results; for example, the height or density of the retaining wall can be increased to enhance the protection effect in areas with severe soil erosion; the plant species and configuration mode can be adjusted to improve the vegetation coverage and growth conditions in areas with poor vegetation growth. At the same time, the maintenance and management measures are adjusted in time according to seasonal changes and climatic conditions to ensure the continuity and stability of the prevention and control effect.

[0074] By combining source prevention with process control, and taking engineering measures with overall vegetation protection, we can effectively curb soil and water loss on the slopes of large-scale waste dumps, increase vegetation coverage and survival rates, and enhance the anti-interference ability of waste dump slopes. This is of great significance for promoting the construction of ecological civilization in railway projects and promoting the ecological restoration of temporary land. At the same time, it provides new ideas and methods for the ecological management of waste from similar projects, and has a strong demonstration effect and promotion value for guiding soil and water conservation and ecological restoration of open-pit mine slopes, tailings ponds, etc.

[0075] By constructing a shrub transplant belt on the slope of the slag dump, a better soil and water conservation belt has been formed, which can reduce soil and water loss to a greater extent.

[0076] By constructing a multi-species community configuration model with native plants that adapt to the local climate and soil environment, we not only prevent the risk of invasion of alien species, but also increase the coverage of native plants on the slag dump to more than 70%, making the vegetation more stable and sustainable.

[0077] The main materials used are all from the natural distribution areas of native plants, and no auxiliary materials and biochemical reagents are used. The materials are easy to collect, low in cost, good in efficiency, and do not cause environmental pollution. They are suitable for large-scale use in vegetation restoration of slag dumps in subalpine shrub areas.

[0078] It can greatly improve the integrity and stability of the vegetation structure on the slope of the slag dump, and can be directly applied to the restoration and reconstruction of slag dump vegetation in subalpine shrub areas, thereby achieving considerable ecological and economic benefits.

[0079] By constructing a three-dimensional comprehensive prevention and control system of "slope foot protection - platform drainage - slope matrix layer reconstruction - native plant community configuration", we have strengthened matrix improvement, selected suitable plants, and taken multiple measures to reduce soil and water loss, ensure project safety, and improve the ecological environment.

[0080] After 6 months of vegetation restoration, the total coverage of the slag dump slope increased by 31%-50%, the shrub coverage increased by about 1%, the herb coverage increased by 30%-50%, and the number of species increased by 11%-39%. The amount of soil erosion decreased by 47%, the sediment production decreased by 74%, and the stability of the slope was significantly improved.

[0081] The use of native plants for vegetation restoration avoids the ecological risks that may be brought by alien species and is conducive to maintaining the regional ecological balance. By constructing a multi-species community configuration model, the species diversity and richness of the restoration area are improved, and the community succession process in the wound recovery area is accelerated.

[0082] By constructing a three-dimensional comprehensive prevention and control system of "slope foot protection - platform drainage - slope matrix layer reconstruction - native plant community configuration", the total coverage of the slag dump slope vegetation was increased by 31%-50% after 6 months of restoration, the number of species increased by 11%-39%, soil erosion was reduced by 47%, and sediment production was reduced by 74%. At the same time, the economic cost was saved by 20-30%, and it did not cause environmental pollution. The operation is simple and easy to promote, which significantly improved the ecological stability and biodiversity of the slag dump slope, with significant comprehensive benefits.

[0083] Example 2

[0084] (1) Site conditions of the slag dump: The implementation area is located at the entrance of a No. 2 tunnel, with the latitude and longitude of the sample site (E 101.8687, N29.9844) and an altitude of 3255±12m. The average slope of the first-level slope of the slag dump is about 30 degrees, the slope length is 33m, the designed slope ratio is 1:2.75, and the vertical height is about 12m.

[0085] (2) Reconstruction of vegetation layer: Field plot experiments were carried out simultaneously at the waste dump. The field plot experiments were arranged on the first step of the waste dump, with a total of 12 plots, each plot was 3×8m, and the plots were separated by iron sheets; the thickness of the vegetation layer in each plot was 15cm. At the bottom of the vegetation layer, the optimal impermeable layer configuration scheme in Section 2.1 was used to construct an impermeable layer with a thickness of 3cm. The plant configuration used tall fescue, alkali grass, ryegrass, bluegrass, prunus tenuifolia, and sweet clover, and the ratio of planting was 4:2:1:1:1:1. The grass seeds were planted by artificial broadcasting, and the density was 30g / m 2 The sample plots were surveyed and sampled at 0d, 60d, 90d, 180d, and 360d.

[0086] (3) Construction of transplant belts: Three transplant belts were dug at the top, middle and bottom of the side slope of the slag dump. The width of the transplant belts was 2m, the depth was about 0.3m, and each transplant belt was 12m long. The distance between the three transplant belts in the transverse direction was about 12m. Two shrub transplant belts were dug along the slope. The width of the transplant belts was 2m, the depth was about 0.3m, and each transplant belt was 36m long. The distance between the two transplant belts along the slope was about 12m.

[0087] (4) Topsoil covering: Use machinery and manual labor to cover the topsoil of the slag dump slope. The thickness of the soil layer covering the transplanting zone is about 45 cm, and the thickness of the soil layer covering the planting area is 20 cm. The required topsoil is the original topsoil of the slag dump.

[0088] (5) Transplanting shrubs with transplanting belts:

[0089] ① Species selection: The shrubs transplanted in the transplanting belt include Spiraea slender-branched, Cotoneaster chinensis, Salix alpinia, Ribes, Rosa rugosa, Honeysuckle, Rhododendron grandiflorum, and Berberis vulgaris.

[0090] ②Transplanting time: early May 2022, when new buds sprout and before leaves unfold.

[0091] ③ Obtaining shrub seedlings: Select shrub seedlings with a height of less than 2 meters, which are relatively young and vigorously growing. Use an excavator to dig out the entire shrub, and carry as much native soil as possible during digging to minimize root loss.

[0092] ④ Shrub transplanting: Dig a suitable transplanting pit according to the size of the shrub root system, and cover the transplanting pit with soil about 20cm. Place the shrub seedling in the middle of the pit, ensuring that the trunk is vertical. Fill a part of the soil, tamp it down with your feet, and repeat the above steps until the topsoil of the tree pit is slightly lower than the ground of the slag field. The transplanting plant spacing is determined according to the size of the shrub seedling, and can be adjusted flexibly. The average plant spacing is about 1m.

[0093] (6) Tree Transplantation: Purchase 5-6 year old spruce and 2-3 year old poplars. Dig appropriate transplanting pits according to the root size of the trees. Cover the pits with 20 cm of soil. The pits should be approximately 50 cm × 50 cm × 50 cm. The spacing between rows should be approximately 5 m × 5 m. Spruce and poplars should be planted alternately.

[0094] (7) Pruning branches: After transplanting, trees and shrubs should be moderately pruned.

[0095] (8) Watering for planting: After transplanting, dilute the tree rooting agent 600 times and irrigate the transplanting hole in small amounts several times until it is thoroughly watered.

[0096] (9) Seeding: Sow the shrub grass seeds in the planting area on the slope of the slag field and the blank area of ​​the transplanting belt, and then rake it gently with a harrow. The sowing rates of each species are: Sweet clover (5g / m 2 ), Nepal yellow flower (15g / m 2 ), Berberis spicata (1.5 g / m 2 ), Nepal sorrel (2g / m 2 ), Potentilla pubescens (1.5 g / m 2 )、Grassroot (1.5g / m 2 ), Artemisia selengensis (5g / m 2 )、Spiraea (1g / m 2 )、High-bush pearl bush (1.5g / m 2 ).

[0097] (10) Non-woven fabric covering: After sowing, cover the planting area with easily degradable lightweight non-woven fabric. Remove the non-woven fabric after one month.

[0098] (11) Post-production care: One month after sowing, complete irrigation, and then the plants grow under natural climatic conditions.

[0099] (12) Effectiveness evaluation: After transplanting, three fixed plots of 3m×3m were arranged in each transplanting belt and planting belt to track the total vegetation cover and species number dynamics. The survival rate of transplanted trees and shrubs and the emergence rate of sown shrubs and grasses were investigated. At the same time, the sample collection work for soil quality investigation and the evaluation of soil water conservation capacity were completed. Six months after vegetation restoration, the total coverage of the landfill slope increased by 31%, the shrub coverage increased by about 1%, the herbaceous coverage increased by 30%, and the number of species increased by 11%. Soil and water loss decreased by 43%, and sediment production decreased by 67%.

[0100] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A three-dimensional comprehensive prevention and control method for soil and water loss in large-scale waste dumps, characterized by: The following steps are involved: S1. Slope foot protection: a retaining wall is formed by combining artificial synthetic materials with sand and soil filling. Drain holes are set at the bottom of the retaining wall to drain water behind the wall; S2. Construct a platform intercepting drainage ditch. The design of the drainage ditch shall determine the size, depth and slope of the ditch according to the catchment area of ​​the slope, rainfall intensity and soil permeability factors; S3. Reconstruction of soil matrix S3.

1. The bottom stabilization layer uses crushed stone with a particle size of 20-40 mm as the stabilization layer material, which is mechanically compacted by an excavator and a roller, with a compaction degree of not less than 90%; S3.2, middle maturation layer, laying the waste residue maturation bacteria agent composite material on the stabilization layer as the maturation layer; S3.3, surface vegetation layer, a vegetation layer is constructed on top of the mature layer, using humus soil and soil-fixing, water-retaining, crusting and anti-corrosion materials mixed in a ratio of 4:1; S4. Constructing the vegetation layer S4.1, material selection, composite materials with high-producing strains of extracellular polymers (EPS) as the core; S4.

2. Construction: Before constructing the vegetation layer, the mature layer should be leveled to ensure that there are no large particles or depressions on the surface; S5. Multi-species plant community configuration S5.

1. Selection of native plants: Conduct detailed investigations on the climate and soil conditions of different ecological types and select suitable native plant species; S5.

2. Diversity configuration: the ratio of trees, shrubs and herbaceous plants should be controlled at 1:3:6; S6. Planting and maintenance management S6.

1. Planting technology: choose the time and method of planting according to the growth characteristics of plants and seasonal changes; S6.

2. Maintenance and management: irrigate 2-3 times a month to ensure the water required for normal growth of plants; S7. Build a comprehensive prevention and control system; S8. Effectiveness monitoring and evaluation: Regularly monitor and evaluate the effectiveness of the prevention and control system.

2. A three-dimensional comprehensive prevention and control method for soil and water loss in a large-scale waste dump as claimed in claim 1, characterized in that: In step S1, the synthetic material includes geogrid and geotextile.

3. A three-dimensional comprehensive prevention and control method for soil and water loss in a large-scale waste dump as claimed in claim 1, characterized in that: In step S2, the drainage ditch is provided with a connecting pipe or a drop well to ensure smooth drainage.

4. A three-dimensional comprehensive prevention and control method for soil and water loss in a large-scale waste dump as claimed in claim 1, characterized in that: In step S3.2, the maturation layer is formed by mixing high-efficiency phosphate-solubilizing, potassium-solubilizing and nitrogen-fixing microbial strains with organic fertilizers and water-retaining agents, and the thickness of the maturation layer is 25 cm.

5. A three-dimensional comprehensive prevention and control method for soil and water loss in a large-scale waste dump as claimed in claim 1, characterized in that: In step S3.3, the thickness of the vegetation layer is 12 cm, and it is evenly sprayed on the surface of the maturation layer by a sprayer.

6. A three-dimensional comprehensive prevention and control method for soil and water loss in a large-scale waste dump as claimed in claim 1, characterized in that: In step S5.1, the native plant species include spruce, willow, sweet clover, Elymus ovata, Potentilla fruticosa and Spiraea odorifera.

7. A three-dimensional comprehensive prevention and control method for soil and water loss in a large-scale waste dump as claimed in claim 1, characterized in that: In step S7, the construction of a comprehensive prevention and control system includes three-dimensional comprehensive prevention and control and optimization and adjustment; The three-dimensional integrated prevention and control is to organically combine the technical means of slope foot protection, platform interception and drainage, slope matrix layer reconstruction and multi-species plant community configuration; The optimization and adjustment is to optimize and adjust the comprehensive prevention and control system according to the actual situation of the slope and the monitoring results.

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