Ecological restoration method and application of rock mine slope in high altitude ecological fragile zone

Abstract

This invention provides a method and application for the ecological restoration of rock mine slopes in ecologically fragile high-altitude areas, specifically relating to the field of ecological environment restoration technology. The ecological restoration method includes: leveling the rock mine slope in an ecologically fragile high-altitude area, then restoring the slope's topography by covering it with topsoil; constructing a masonry diamond-shaped grid structure for protection on the rock mine slope, planting native shrubs and grasses within the grid; installing an integrated water and fertilizer drip irrigation system on the rock mine slope; and finally, applying sprayed concrete or constructing slope supports to prevent soil erosion on the slope surface; wherein the altitude of the high-altitude area is >4000m. This ecological restoration method provides strong technical support for the ecological restoration of rock mine slopes in ecologically fragile high-altitude areas, and also provides important guarantees and references for ecological restoration work after mining in high-altitude regions.

Description

Technical Field

[0001] This invention relates to the field of ecological environment restoration technology, and in particular to an ecological restoration method and application for rocky mine slopes in ecologically fragile high-altitude areas. Background Technology

[0002] High-altitude, ecologically fragile rock mine slopes often face challenges during mining operations, including large-scale exposure, poor soil fertility, difficulty in vegetation growth, and severe soil erosion. These problems not only severely damage the local ecosystem but also pose significant challenges to ecological restoration. Traditional low-altitude mine slope restoration methods have proven ineffective in high-altitude areas, primarily due to poor ecological stability, poor vegetation growth, and limited durability of restoration results. Furthermore, a mature technological system is currently lacking to achieve long-term ecological restoration of rock mine slopes in high-altitude, ecologically fragile areas.

[0003] The specific ecological problems faced by rocky mine slopes in high-altitude, ecologically fragile areas include:

[0004] Lack of comprehensive ecological restoration methods: The ecological environment of high-altitude and cold regions is extremely sensitive and fragile, and once damaged, restoration is extremely difficult. Maintaining soil fertility, promoting plant growth, and carrying out construction operations are all significantly more challenging than in low-altitude areas. Therefore, there is an urgent need to develop a set of ecological restoration methods suitable for mine slopes in ecologically fragile high-altitude areas, especially native and near-natural vegetation restoration techniques.

[0005] Ecological restoration is inefficient and its effects are difficult to sustain: Existing greening techniques on the market, such as netting and topsoil spraying, vegetated concrete, high-density aggregate spraying, and geocells, have not yet been practically applied in the greening of rocky slopes in high-altitude mines. These technologies lack attention to the growth space and plant stability of ecologically fragile areas, and their indiscriminate application may lead to "acclimatization problems," resulting in low ecological restoration efficiency and unsustainable restoration effects.

[0006] Soil reconstruction and improvement are challenging: traditional remediation methods fail to make appropriate use of the surrounding soil and plant resources, nor do they specifically modify the slope soil into high-quality soil suitable for native plant growth. This makes it difficult to effectively solve the problems of soil reconstruction and plant growth on high-altitude mine slopes.

[0007] Soil and water loss is a serious problem: high-altitude areas experience strong winds and sandstorms, and freshwater resources are scarce. Traditional restoration methods have failed to fully consider the impact of wind on plant growth and soil and water loss. Therefore, existing methods have limited effectiveness in treating mine slopes in ecologically fragile areas and are unable to effectively address issues such as large-scale exposure of rock slopes, severe damage to landforms, and significant soil and water loss in high-altitude ecologically fragile areas.

[0008] In view of this, the present invention is hereby proposed. Summary of the Invention

[0009] One of the objectives of this invention is to provide an ecological restoration method for rocky mine slopes in ecologically fragile high-altitude areas, aiming to solve at least one of the aforementioned technical problems in the prior art.

[0010] The second objective of this invention is to provide an application of an ecological restoration method for rocky mine slopes in ecologically fragile high-altitude areas.

[0011] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted:

[0012] The first aspect of this invention provides an ecological restoration method for rocky mine slopes in ecologically fragile high-altitude areas, comprising the following steps:

[0013] The slopes of rock mines in high-altitude ecologically fragile areas were leveled, and then the landform of the rock mine slopes was restored by covering them with topsoil.

[0014] The rocky mine slope is protected by a masonry diamond grid structure, and native shrubs and grasses are planted within the grid structure.

[0015] Install an integrated water and fertilizer drip irrigation system on the slope of the rocky mine;

[0016] Finally, spray anchor protection or slope support construction is carried out on the slope surface of the rock mine to prevent soil erosion.

[0017] The altitude of the high altitude is greater than 4000m.

[0018] Furthermore, the slopes of rock mines in high-altitude, ecologically fragile areas are leveled, including:

[0019] The accumulated rocks on the slope of the rock mine are cleared, and the uneven parts of the slope caused by excavation, occupation, and collapse are repaired to make it flat.

[0020] Furthermore, the landform of the rocky mine slope is restored by covering it with topsoil, including:

[0021] In areas with good vegetation growth near the rocky mine slope, turf was peeled off and used to cover the rocky mine slope;

[0022] The thickness of the turf is ≥30cm.

[0023] Furthermore, in the areas where vegetation grows well, the soil texture is sandy to loamy clay, the effective soil layer thickness is ≥10cm, and the soil bulk density is ≤1.5g / m³. 3 Gravel content ≤50%, pH value 6.0~8.5, organic matter ≥0.3%.

[0024] Furthermore, the rock mine slope is protected by a masonry rhomboid lattice structure, within which native shrubs and grasses are planted, including:

[0025] On the rocky mine slope, rhomboid units are constructed by masonry and connected to each other, with a side length of 1.5 to 2.5 m and a masonry thickness of 0.35 to 0.55 m, to obtain rhomboid grid protection; native shrubs and grasses are planted in the rhomboid grid.

[0026] The native shrubs and grasses include at least one of the following: Leymus chinensis, Leymus chinensis, Artemisia argyi, Agrimonia pilosa, Poa annua, and Leymus chinensis.

[0027] Furthermore, an integrated water and fertilizer drip irrigation system is installed on the slope of the rocky mine, including:

[0028] An elevated water storage tank is set up at the top of the rock mine slope, and then a water supply network is set up in the rock mine slope area. Drip emitters or drip irrigation pipes are installed in the water supply network to drip water or liquid organic fertilizer into the soil in the form of drops.

[0029] Furthermore, the shotcrete and anchor slope protection includes:

[0030] Anchor bolts are installed on the slope of the rock mine, and then shotcrete is sprayed to form the first concrete layer. After the first layer of concrete has initially set, steel mesh is laid on the slope and firmly connected to the anchor bolts. Shotcrete is then sprayed to form the second concrete layer, ensuring that the steel mesh is completely wrapped in concrete to form an integral shotcrete and anchor support structure.

[0031] Furthermore, the constructed slope support includes:

[0032] The slope surface of the rock mine is repaired, and frame beams, retaining walls, and anchor bolts are installed. Then, shotcrete is sprayed to form the first concrete layer. After the first layer of concrete has initially set, steel mesh is laid on the slope and firmly connected to the anchor bolts. Shotcrete is then sprayed to form the second concrete layer, ensuring that the steel mesh is completely wrapped in concrete to form an integral slope support.

[0033] Furthermore, the liquid organic fertilizer includes an aqueous solution of urea or an aqueous solution of potassium dihydrogen phosphate.

[0034] Preferably, the concentration of the liquid organic fertilizer is 0.1 to 0.5 wt%.

[0035] The second aspect of this invention provides the application of the ecological restoration method described above in the restoration of rocky mine slopes in ecologically fragile high-altitude areas.

[0036] Compared with the prior art, the present invention has at least the following beneficial effects:

[0037] The ecological restoration method provided by this invention involves leveling the slopes of rocky mines in ecologically fragile high-altitude areas and restoring the slope topography by covering them with topsoil. This effectively improves the soil structure of the slopes, providing a good foundation for subsequent vegetation restoration. Topsoil covering increases soil fertility and improves the physical and chemical properties of the soil, thus creating a more favorable environment for plant growth. Constructing a diamond-shaped masonry structure on the slope and planting native shrubs and grasses within the structure not only enhances slope stability but also provides suitable growing space for plants. This structure effectively prevents soil erosion while providing support and protection for native plants, promoting rapid vegetation recovery and growth. Installing an integrated water and fertilizer drip irrigation system enables precise irrigation and fertilization, improving the efficiency of water and fertilizer utilization. This system can scientifically regulate water and fertilizer requirements according to the plants' needs, avoiding water waste and soil compaction problems caused by traditional irrigation methods. Simultaneously, drip irrigation technology reduces air humidity, decreasing the probability of pests and diseases, further improving plant growth quality and ecological restoration effects. Finally, by using sprayed anchors or constructing slope support measures, the stability of the slope can be further enhanced, effectively preventing soil erosion, improving the slope's resistance to weathering and erosion, and providing a long-term and stable guarantee for ecological restoration.

[0038] The application provided by this invention, given the advantages of the above-mentioned ecological restoration method, provides strong technical support for the ecological restoration of rock mine slopes in ecologically fragile high-altitude areas, and also provides important guarantees and references for ecological restoration work after mining in high-altitude areas. Attached Figure Description

[0039] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0040] Figure 1 A schematic diagram illustrating the process of an ecological restoration method for rocky mine slopes in ecologically fragile high-altitude areas;

[0041] Figure 2 This is a schematic diagram illustrating another method for ecological restoration of rocky mine slopes in high-altitude, ecologically fragile areas. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0043] In the following, the terms “comprising,” “having,” and their cognates, which may be used in various embodiments of the invention, are intended only to indicate a particular feature, number, step, operation, element, component, or combination thereof, and should not be construed as excluding, firstly, the presence of one or more other features, numbers, steps, operations, elements, components, or combinations thereof, or adding the possibility of one or more features, numbers, steps, operations, elements, components, or combinations thereof.

[0044] Rocky mine slopes in high-altitude, ecologically fragile areas have the following characteristics:

[0045] 1. Complex geological structure

[0046] Fragmented rock mass: The rock mass on the slopes of rock mines in high-altitude areas is usually quite fragmented, with obvious joints and fissures. This fragmented rock mass structure makes the slopes less stable and prone to geological disasters such as collapses and landslides.

[0047] Structural plane development: Multiple sets of dominant structural planes exist within the rock mass. The distribution, combination, and density of these structural planes have a significant impact on slope stability. For example, bedding slopes may be at risk of local wedge sliding because the dip of the rock bedding plane is opposite to the slope aspect.

[0048] 2. Harsh climatic conditions

[0049] Cold climate: High-altitude areas have low temperatures, long and cold winters, and short and cool summers. These climatic conditions result in short plant growth cycles and make vegetation restoration difficult.

[0050] Strong winds and sandstorms: High-altitude areas experience strong winds and frequent sandstorms. This not only adversely affects plant growth but also exacerbates soil erosion.

[0051] 3. Fragile ecological environment

[0052] Poor soil fertility: Soil fertility is generally low in high-altitude areas, making it difficult to support plant growth. This poses a significant challenge to vegetation restoration on mine slopes.

[0053] Low vegetation cover: Due to cold climate and poor soil, vegetation cover is low in high-altitude areas. After mining, slope vegetation is severely damaged, making ecological restoration difficult.

[0054] 4. Poor slope stability

[0055] Steep slopes: High-altitude mine slopes are typically steep with a large gradient. These steep slopes have poor stability and are prone to geological disasters under complex geological conditions and harsh climates.

[0056] The instability modes are diverse: instability modes of high-altitude rocky mine slopes include rockfall, planar sliding, wedge failure, toppling failure, and circular sliding failure. The existence of these instability modes makes slope stability analysis and management more complex.

[0057] Based on this, the present invention provides an ecological restoration method for rocky mine slopes in ecologically fragile high-altitude areas, such as... Figure 1 As shown, the specific steps include:

[0058] S102. The slopes of rock mines in high-altitude ecologically fragile areas are leveled, and then the landform of the rock mine slopes is restored by covering them with topsoil. The altitude of the high-altitude area is >4000m.

[0059] Ecologically fragile areas refer to regions where the ecosystem is less resistant to disturbance, prone to degradation, and difficult to restore.

[0060] In the specific implementation process, the first step is to clear the slopes of high-altitude rock mines, removing loose rocks, topsoil, debris, and obstacles that may affect subsequent construction. This step helps eliminate potential geological hazards, such as loose rocks and landslides. The slope gradient and shape are then adjusted to achieve a relatively stable state. For example, through measures such as slope cutting and unloading, the slope of the mining pit and slag heap is controlled within a reasonable range, such as less than 26°, thereby providing stable site conditions for subsequent ecological restoration.

[0061] Imported soil refers to soil suitable for plant growth transported from other areas. Given the unique environmental conditions of high-altitude, ecologically fragile areas, imported soil needs careful preparation to meet the basic needs of vegetation growth. The imported soil is then evenly spread over the leveled slope. The thickness of the topsoil cover needs to be determined based on the specific conditions of the slope and the requirements for vegetation restoration; generally, it should be thick enough to support plant root growth. By covering the slope with imported soil, a layer of fertile and water-retaining soil is provided, thereby restoring the slope's topography and creating favorable conditions for vegetation growth. This helps improve the ecological environment of the slope and promotes rapid vegetation recovery and growth.

[0062] The above-mentioned leveling and topsoil covering measures can effectively improve the soil conditions of rocky mine slopes in high-altitude ecologically fragile areas, laying the foundation for subsequent vegetation restoration and ecological restoration.

[0063] S104. The rock mine slope is protected by a masonry diamond grid structure, and native shrubs and grasses are planted within the grid structure.

[0064] A rhomboid lattice structure is constructed using masonry (such as rubble or stone blocks). This structure effectively disperses water flow and reduces rainwater erosion of the slope. The thickness of the masonry is generally 35cm to 55cm, and the specific thickness can be adjusted according to the stability requirements of the slope and environmental conditions.

[0065] The grid structure is embedded 10cm to 30cm into the slope to enhance its overall stability and prevent rockfall. Drainage holes, typically made of PVC pipes with a diameter of at least 100mm, are installed within the grid to drain rainwater from the slope and prevent groundwater infiltration.

[0066] Expansion joints are installed at intervals of 20m to 25m in the grid protection structure. The joints are about 2cm wide and filled with materials such as asphalt hemp rope to accommodate the temperature deformation and uneven settlement of the slope.

[0067] Select native shrubs and herbaceous plants adapted to local climate and soil conditions. These plants are characterized by strong resilience, drought tolerance, and tolerance to poor soil, enabling them to grow in harsh environments. Planting native shrubs and grasses can effectively improve the ecological environment of slopes, increase vegetation cover, and reduce soil erosion. Plant roots can penetrate deep into the soil, enhancing the soil's shear strength and further improving slope stability. Through plant growth and succession, the ecosystem function of the slope is gradually restored, promoting ecological balance.

[0068] S106. Install an integrated water and fertilizer drip irrigation system on the slope of the rocky mine.

[0069] The integrated water and fertilizer drip irrigation system is an ecological restoration technology that combines irrigation and fertilization. By precisely controlling the amount of irrigation water and fertilizer applied, this system achieves a rational balance of water and fertilizer, improving plant growth efficiency while reducing soil erosion and environmental pollution. In the ecological restoration of rocky mine slopes, the integrated water and fertilizer drip irrigation system can effectively address the problems of water scarcity and insufficient soil fertility in high-altitude areas, providing strong support for vegetation restoration.

[0070] S108. Finally, spray anchor protection or construct slope support for the rock mine slope to prevent soil erosion.

[0071] Shotcrete and anchor protection is an engineering measure that reinforces slopes by spraying concrete and using anchor bolts. Its main function is to prevent weathering, erosion, and rainwater scouring of the slope rock mass, thereby improving the stability of the slope.

[0072] Slope protection is a comprehensive slope protection measure that is suitable for areas with severe topographic changes and significant soil erosion.

[0073] By using shotcrete and anchor slope protection or constructing slope supports, soil and water loss on high-altitude rock mine slopes can be effectively prevented, slope stability can be enhanced, and ecological restoration can be guaranteed.

[0074] The ecological restoration method provided by this invention involves leveling the slopes of rocky mines in ecologically fragile high-altitude areas and restoring the slope topography by covering them with topsoil. This effectively improves the soil structure of the slopes, providing a good foundation for subsequent vegetation restoration. Topsoil covering increases soil fertility and improves the physical and chemical properties of the soil, thus creating a more favorable environment for plant growth. Constructing a diamond-shaped masonry structure on the slope and planting native shrubs and grasses within the structure not only enhances slope stability but also provides suitable growing space for plants. This structure effectively prevents soil erosion while providing support and protection for native plants, promoting rapid vegetation recovery and growth. Installing an integrated water and fertilizer drip irrigation system enables precise irrigation and fertilization, improving the efficiency of water and fertilizer utilization. This system can scientifically regulate water and fertilizer requirements according to the plants' needs, avoiding water waste and soil compaction problems caused by traditional irrigation methods. Simultaneously, drip irrigation technology reduces air humidity, decreasing the probability of pests and diseases, further improving plant growth quality and ecological restoration effects. Finally, by using sprayed anchors or constructing slope support measures, the stability of the slope can be further enhanced, effectively preventing soil erosion, improving the slope's resistance to weathering and erosion, and providing a long-term and stable guarantee for ecological restoration.

[0075] In another embodiment of the present invention, an ecological restoration method for rocky mine slopes in ecologically fragile high-altitude areas is described, such as... Figure 2 As shown, it includes the following steps:

[0076] S202. Clean up the piled rocks on the slope of the rock mine and repair the uneven parts of the slope caused by excavation, occupation and collapse to make it flat.

[0077] S204. In areas with good vegetation growth near the rock mine slope, turf is peeled off and used to cover the rock mine slope; wherein the thickness of the turf is ≥30cm.

[0078] Furthermore, in the areas where vegetation grows well, the soil texture is sandy to loamy clay, the effective soil layer thickness is ≥10cm, and the soil bulk density is ≤1.5g / m³. 3 Gravel content ≤50%, pH value 6.0~8.5, organic matter ≥0.3%.

[0079] It should be noted that soil texture from sandy to loamy clay means that the soil particle composition is between sandy and loamy clay, covering a range of soil texture types from sandy to loamy clay.

[0080] The specific process for stripping turf is as follows: Turf from well-vegetated areas near the mining area is stripped to a thickness of at least 30cm, and the stripped turf is then piled up. Subsequently, maintenance measures are implemented on this turf to ensure it can effectively restore vegetation when subsequently used for mine slope mulching.

[0081] Specific maintenance measures include: regular watering, once every two weeks, using sprinkler irrigation; and application of organic fertilizer, using a 1:10 mixture of microbial fertilizer and organic farmyard manure, spread evenly on the turf surface after mowing or before the peak growth period, allowing it to be absorbed into the soil through sprinkler irrigation or natural rainfall to promote turf growth. These measures provide healthy, well-growing turf resources for the ecological restoration of mine slopes.

[0082] S206. On the slope of the rock mine, rhomboid units are constructed by masonry and connected to each other, with a side length of 1.5 to 2.5 m and a masonry thickness of 0.35 to 0.55 m, to obtain rhomboid grid protection; native shrubs and grasses are planted in the rhomboid grid.

[0083] The native shrubs and grasses include at least one of the following: Leymus chinensis, Leymus chinensis, Artemisia argyi, Agrimonia pilosa, Poa annua, and Leymus chinensis.

[0084] The construction is carried out using the grouting method. First, a layer of cement mortar with a grade of M7.5 to M10 is laid on the foundation or lower layer of stones. Then, the stones are placed on the mortar, and it is ensured that the gaps between the stones are filled with mortar.

[0085] S208. A high-level water storage tank is set up at the top of the rock mine slope, and then a water supply network is set up in the rock mine slope area. Drip emitters or drip irrigation pipes are installed in the water supply network to drip water or liquid organic fertilizer into the soil in the form of drips.

[0086] The integrated water and fertilizer drip irrigation system installed on the rocky mine slope uses polyvinyl chloride or polyethylene pipes. The main pipe diameter is 40–60 mm, branch pipe diameter is 20–30 mm, and capillary pipe diameter is 10–15 mm. Branch pipes are connected by tees or crosses, with a spacing of 10–30 m. Capillary pipes are connected to branch pipes via bypass fittings, and the spacing between drippers on the capillary pipes is 0.5–1 m. Irrigation is by drip irrigation, occurring every 5–7 days, with each irrigation lasting 30–60 minutes.

[0087] Liquid organic fertilizers, such as urea and potassium dihydrogen phosphate, which are highly water-soluble, are used at a concentration controlled between 0.1% and 0.5%, and must be stirred thoroughly before use. Fertilization should be carried out 10-15 minutes after drip irrigation begins, with the frequency of fertilization matching that of irrigation. Through the above configuration and operation steps, this drip irrigation system can efficiently provide water and nutrients to the vegetation on the mine slope, promoting vegetation growth while reducing water waste and environmental pollution, and improving the ecological restoration effect.

[0088] S210. Spray anchoring or constructing slope support for the rock mine slope to prevent soil erosion.

[0089] Shotcrete and anchor protection is suitable for loose slopes. Specifically, in S2102, anchor bolts are installed on the slope surface of the rocky mine slope, and then shotcrete is sprayed to form the first concrete layer. After the first layer of concrete has initially set, steel mesh is laid on the slope surface and firmly connected to the anchor bolts. Shotcrete is then sprayed to form the second concrete layer, ensuring that the steel mesh is completely wrapped by the concrete to form an integral shotcrete and anchor support structure.

[0090] In practice, shotcrete and anchor slope protection is carried out according to the following process:

[0091] Anchor bolt installation: HRB400 grade steel anchor bolts with a diameter of 25mm are used, with a horizontal and vertical spacing of 2m. The length of a single anchor bolt is 6–9m, and the inclination angle is 20°. Drilling is carried out according to design requirements, ensuring the borehole diameter matches the anchor bolt diameter and the drilling depth meets the anchor bolt length requirements. The anchor bolts are inserted into the boreholes and anchored using suitable anchoring materials (such as cement mortar or anchoring agent) to ensure sufficient bond strength between the anchor bolt and the rock mass.

[0092] Reinforcing mesh construction: Reinforcing mesh is made using 8mm diameter steel bars, with a mesh spacing of approximately 20cm. The reinforcing mesh should be tied or welded according to design requirements. The steel bars should be lapped in both directions, with the lap length meeting relevant specifications, and double-sided welding should be used to ensure a secure connection. The reinforcing mesh should be firmly connected to the anchor bolts to ensure that it can share the load with the anchor bolts during shotcreting.

[0093] Shotcrete Construction: C25 grade concrete is used for shotcreting. First, a first layer of concrete is sprayed, 3-4 cm thick, to form a preliminary protective layer and provide support for the steel mesh installation. After the first layer of concrete has initially set, the steel mesh is laid on the slope and securely connected to the anchor bolts. A second layer of concrete is then sprayed to the designed thickness of 10-15 cm, ensuring the steel mesh is completely encased in concrete, forming a unified shotcrete-anchor support structure. During shotcreting, the spraying speed and distance should be controlled to ensure the uniformity and density of the concrete, while avoiding excessive impact on the slope.

[0094] or,

[0095] For slope areas with significant changes in surface topography, slope protection is constructed. Specifically: S2104, the rock mine slope is repaired, then frame beams, retaining walls, and anchor bolts are installed, followed by shotcrete to form the first concrete layer; after the first layer of concrete has initially set, steel mesh is laid on the slope and firmly connected to the anchor bolts; shotcrete continues to form the second concrete layer, ensuring that the steel mesh is completely encased in concrete, forming an integral slope protection.

[0096] In the specific implementation process, the construction of slope protection shall be carried out according to the following procedure:

[0097] Slope cleaning and trimming: The slope surface is cleaned, loose rocks, debris, and topsoil are removed to ensure a smooth slope. Areas with severely altered topography are partially trimmed to restore the original surface water catchment conditions and landscape form.

[0098] Anchor bolt construction: HRB400 grade steel anchor bolts with a diameter of 25mm are used. Each anchor bolt is 3-4m long, and the spacing between anchor bolts is not less than 1.5m. Drilling is carried out according to design requirements. The drilling depth should meet the anchor bolt length requirements, and the drilling direction should be consistent with the slope angle. The anchor bolts are inserted into the drilled holes and anchored using suitable anchoring materials (such as cement mortar or anchoring agent) to ensure sufficient bond strength between the anchor bolt and the rock mass.

[0099] Reinforcing mesh construction: Reinforcing mesh is made using steel bars with a diameter of 8-10mm, with a mesh spacing of generally 20-30cm. The reinforcing mesh should be securely connected to the anchor bolts to ensure coordinated stress distribution during shotcreting.

[0100] Shotcrete application: C25 grade concrete is used for shotcreting, with a thickness of 6-10 cm. During shotcreting, the spraying speed and distance should be controlled to ensure the uniformity and density of the concrete, while avoiding excessive impact on the slope.

[0101] Secondly, the present invention provides the application of the ecological restoration method described above in the restoration of rocky mine slopes in ecologically fragile high-altitude areas.

[0102] The application provided by this invention, given the advantages of the above-mentioned ecological restoration method, provides strong technical support for the ecological restoration of rock mine slopes in ecologically fragile high-altitude areas, and also provides important guarantees and references for ecological restoration work after mining in high-altitude areas.

[0103] Application examples

[0104] In 2021, ecological restoration was carried out on the slopes of the JM copper-lead mine (hereinafter referred to as JM-TQ) in Lhasa, Tibet Autonomous Region, China (altitude 4300-4800m). The specific process is as follows:

[0105] 1. Clean up the piled rocks on the slope of the JM-TQ mine, and repair the uneven parts of the slope caused by excavation, occupation and collapse to make it flat.

[0106] 2. In the area near the slope of the JM-TQ mine where vegetation grows well, the soil texture was determined to be light loam or sandy loam, with an effective soil layer thickness of approximately 65 cm and a soil bulk density of 1.2–1.5 g / m³. 3 The gravel content is approximately 15%, the pH value is approximately 4.9–6.6, and the organic matter content is approximately 12–22%. A layer of turf approximately 30 cm thick was simultaneously applied to the slope of the JM-TQ mine to be restored.

[0107] 3. On the slope of the JM-TQ mine, lay a layer of cement mortar on the foundation or lower layer of stones. The grade of the cement mortar is M7.5. Then place the stones on the mortar, ensuring that the gaps between the stones are filled with mortar and connected to form rhomboid units with a side length of 2m and a masonry thickness of 0.5m to obtain a rhomboid grid protection structure. Plant sand-fixing grass in the rhomboid grid structure.

[0108] 4. An elevated reservoir is constructed at the top of the slope of the JM-TQ mine to store irrigation water. Then, a water supply network is laid across the slope area. This network consists of pipes of different diameters: main pipes are 50mm in diameter, branch pipes are 25mm in diameter, and capillary pipes are 15mm in diameter. The main pipes transport water from the elevated reservoir to the slope. Branch pipes are laid longitudinally along the slope, while capillary pipes extend from the branch pipes into the vegetated areas of the slope. Branch pipes are connected by T-junctions or four-way fittings, with a spacing of 20m. Capillary pipes are connected to branch pipes by bypass fittings, and the drippers on the capillary pipes are spaced 1m apart. Drippers or drip irrigation pipes are installed on the capillary pipes to precisely drip water or liquid organic fertilizer into the soil, directly reaching the plant roots.

[0109] 5. Shotcrete and anchor protection was carried out on the slope of the JM-TQ mine, using HRB400 grade steel anchor rods with a diameter of 25mm. The horizontal and vertical spacing of the anchor rods was 2m. The length of a single anchor rod was 7m, and the inclination angle of the anchor rod was 20°. The anchor rods were inserted into the drilled holes and anchored with cement mortar.

[0110] The reinforcing mesh is made of 8mm diameter steel bars with a mesh spacing of 20cm. The reinforcing mesh should be tied or welded according to the design requirements. The steel bars should be lapped in both directions, and the lap length should meet the relevant specifications. Double-sided welding should be used to ensure a firm connection of the reinforcing mesh.

[0111] First, a first layer of shotcrete, approximately 3.5 cm thick, is applied using C25 grade concrete to form a preliminary protective layer and provide support for the laying of the reinforcing mesh. After the first layer of concrete has initially set, the reinforcing mesh is laid on the slope and securely connected to the anchor bolts. A second layer of shotcrete is then applied, reaching the designed thickness of 13 cm, ensuring the reinforcing mesh is completely encased in concrete, forming a unified shotcrete-anchor support structure.

[0112] 6. After the above process is completed, maintain the sand-fixing grass by drip irrigation once every 7 days, with each irrigation lasting 45 minutes. Use urea with a mass concentration of 0.3% as the liquid organic fertilizer. Fertilizer should be applied 5 minutes after the start of drip irrigation, and the fertilization frequency should be consistent with the irrigation frequency.

[0113] A 2023 statistical analysis of the ecological restoration achievements of the JM-TQ mine showed that the original topography of the damaged mine slopes was basically restored, meeting the requirements for shrub and grass planting. After restoration, the slope treatment rate reached over 95%, the vegetation coverage rate exceeded 40%, and shrubs and grasses were able to grow. The integrated water and fertilizer drip irrigation system improved fertilizer utilization by over 30% and water resource utilization by over 40%. The overall soil and water conservation rate reached at least 88%.

[0114] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An ecological restoration method for rocky mine slopes in high-altitude ecologically fragile areas, characterized in that, Includes the following steps: The slopes of rock mines in high-altitude ecologically fragile areas were leveled, and then the landform of the rock mine slopes was restored by covering them with topsoil. The rocky mine slope is protected by a masonry diamond grid structure, and native shrubs and grasses are planted within the grid structure. Install an integrated water and fertilizer drip irrigation system on the slope of the rocky mine; Finally, slope protection was constructed on the slope of the rock mine to prevent soil erosion. Wherein, the altitude of the high altitude is >4000m; The method of restoring the landform of the rock mine slope by covering it with topsoil includes: in areas with good vegetation growth near the rock mine slope, peeling off turf and covering it with topsoil. The thickness of the turf is ≥30cm; In the areas with good vegetation growth, the soil texture is sandy to loamy clay, the effective soil layer thickness is ≥10cm, and the soil bulk density is ≤1.5g / cm³. 3 Gravel content ≤50%, pH value 6.0~8.5, organic matter ≥0.3%.

2. The ecological restoration method according to claim 1, characterized in that, Leveling treatment of rock mine slopes in ecologically fragile high-altitude areas includes: The accumulated rocks on the slope of the rock mine are cleared, and the uneven parts of the slope caused by excavation, occupation, and collapse are repaired to make it flat.

3. The ecological restoration method according to claim 1, characterized in that, The rocky mine slope is protected by a masonry rhomboid lattice structure, with native shrubs and grasses planted within the lattice, including: On the rocky mine slope, rhomboid units are constructed by masonry and connected to each other, with a side length of 1.5~2.5m and a masonry thickness of 0.35~0.55m, to obtain rhomboid grid protection; native shrubs and grasses are planted in the rhomboid grid. The native shrubs and grasses include at least one of the following: *Leymus chinensis*, *Leymus chinensis*, *Artemisia argyi*, *Poa annua*, and *Poa chinensis*.

4. The ecological restoration method according to claim 1, characterized in that, Installing an integrated water and fertilizer drip irrigation system on the slope of the rocky mine includes: An elevated water storage tank is set up at the top of the rock mine slope, and then a water supply network is set up in the rock mine slope area. Drip emitters or drip irrigation pipes are installed in the water supply network to drip water or liquid organic fertilizer into the soil in the form of drops.

5. The ecological restoration method according to claim 1, characterized in that, The slope protection construction includes: The slope surface of the rock mine is repaired, and frame beams, retaining walls, and anchor bolts are installed. Then, shotcrete is sprayed to form the first concrete layer. After the first concrete layer has initially set, steel mesh is laid on the slope and firmly connected to the anchor bolts. Shotcrete is then sprayed to form the second concrete layer, ensuring that the steel mesh is completely wrapped in concrete to form an integral slope support.

6. The ecological restoration method according to claim 4, characterized in that, The liquid organic fertilizer includes an aqueous solution of urea or an aqueous solution of potassium dihydrogen phosphate; The concentration of the liquid organic fertilizer is 0.1~0.5wt%.

7. The application of the ecological restoration method according to any one of claims 1 to 6 in the restoration of rocky mine slopes in ecologically fragile high-altitude areas.

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