Slope land preparation and vegetation recovery method

Abstract

The invention relates to a slope land preparation and vegetation restoration method, belongs to the field of ecological restoration, afforestation and water and soil conservation engineering, mainly aims at a rock slope land with a slope angle larger than 15 degrees, and comprises the steps that 1, a key restoration area and a general restoration area are divided according to one of canopy density, NDVI or EVI; (2) fish-scale pit soil preparation and vegetation reconstruction are conducted on the key restoration area; according to the method, the natural evolution process is fully considered and simulated, the damaged sloping field can be restored according to local conditions without excessive treatment, suitable conditions are provided for vegetation growth, a stable environment is constructed to achieve vegetation natural succession, and finally the win-win situation of ecology, landscape and economic benefits is achieved.

Description

Technical Field

[0001] The present invention relates to the fields of ecological restoration, afforestation, and soil and water conservation engineering, and particularly relates to a method for slope land preparation and vegetation restoration or reconstruction. Background Art

[0002] During ecological restoration and forestry land preparation and afforestation, soil site types with harsh natural environments such as drought, barrenness, and rocky desertification are often encountered. Such slopes require artificial intervention means for vegetation restoration. Existing means usually involve rock drilling, soil covering, and planting of trees, shrubs, and herbs. However, the water retention effect of this method is limited and it is prone to surface soil loss. Vegetation under such land preparation conditions often has poor growth or even cannot grow, and the afforestation or vegetation restoration effect is poor and cannot be sustainably developed.

[0003] During the process of slope restoration and vegetation reconstruction, mechanical excavation, soil covering, and vegetation planting often do not fully consider the relationship between rock weathering and soil formation and vegetation. In similar ecological restoration projects, patchy damage often undergoes whole-region treatment, resulting in phenomena such as damage to the original vegetation or over-planting of vegetation.

[0004] Fish-scale pits are a commonly used afforestation means for soil and water conservation. However, there is a lack of transition between the rock layer and the soil layer, and tree species cannot directly weather the bedrock into soil. After excavation in some limestone outcropping areas, fissures develop and may form through-fissures, which cannot achieve the purpose of water retention, resulting in poor vegetation restoration effect. When designing fish-scale pits, factors such as drainage regulation and slope differences are usually not considered. Regardless of the slope, the quantity is calculated only based on the projected area, and during maintenance, the available water storage capacity is often ignored, resulting in phenomena such as drought, waterlogging, and waste. Summary of the Invention

[0005] To solve the above defects, the present invention provides a method for slope land preparation and vegetation restoration. This method fully considers and simulates the natural succession process of the spatial substances required for vegetation growth in the time dimension, and sets a rock-soil transition layer, prepares the land according to local conditions, provides suitable conditions for vegetation growth, and constructs a stable micro-ecosystem to achieve natural succession of vegetation. The specific content is as follows: A method for slope land preparation and vegetation restoration, the slope being a rocky slope with a slope angle greater than 15°, and the land preparation and vegetation restoration method includes: Step 1) Divide the slope into a key restoration area and a general restoration area according to one of the canopy density, normalized difference vegetation index NDVI, or enhanced vegetation index EVI; Step 2) Conduct fish-scale pit land preparation and vegetation reconstruction on the key restoration area. The fish-scale pit land preparation includes topsoil stripping, rock drilling, slag covering, soil covering, and ridge building. The fish-scale pit space formed by topsoil stripping and rock drilling is filled with inner soil layer and slag covering layer from top to bottom in sequence. When there is no topsoil, only rock drilling is carried out. The inner soil layer and the ridge are set as reverse slopes. The vegetation reconstruction includes at least one of trees and shrubs and herbaceous plants; Step 3) Conduct natural restoration on the general restoration area. The main measures include at least one of site enclosure, setting up signboards, replanting and supplementing planting, reseeding, and tending. The vegetation selected for replanting and supplementing planting or reseeding includes at least one of arbors, shrubs, and herbaceous plants.

[0006] The crown density, normalized difference vegetation index (NDVI), or enhanced vegetation index (EVI) are all selected as the maximum values during the growing season, and the growing season is generally summer. The key restoration area has damaged landforms and land destruction, and the surface vegetation habitat is severely affected to a very severe extent, with relatively severe to very severe ecological degradation. The main measures include landform reshaping, soil reconstruction, and vegetation reconstruction. In step 2), topsoil stripping and rock drilling belong to landform reshaping, and slag covering and soil covering belong to soil reconstruction. The general restoration area has good geological stability, slightly damaged landforms, only a small amount of land damage on the surface, and only local vegetation cover and quality are affected. The species habitat conditions are relatively stable, and the ecosystem structure and function are relatively intact. The main measures include natural restoration, including site enclosure, setting up signboards, replanting and supplementing planting, reseeding, and tending. Among them, the natural restoration of vegetation includes replanting and supplementing planting, reseeding, and tending. All the above-mentioned shrubs include climbing plants.

[0007] Further, in step 1), the areas with a crown density less than 30%, a normalized difference vegetation index (NDVI) less than 0.4, or an enhanced vegetation index (EVI) less than 0.3 are defined as the key restoration areas, and the rest are general restoration areas. According to the impact of landform damage and land destruction on the surface vegetation habitat, the areas where the vegetation cannot be restored by natural restoration measures are defined as the key restoration areas. These key restoration areas have no stable site conditions and need to prepare the land and construct suitable site conditions. The ecological degradation in these areas is relatively severe to very severe, and the vegetation cannot grow or grows poorly. Quantitatively shown according to vegetation characteristics: the crown density in these areas is less than 30%, the normalized difference vegetation index (NDVI) is less than 0.4, or the enhanced vegetation index (EVI) is less than 0.3. According to the regulations of the Food and Agriculture Organization of the United Nations, a crown density less than 20% is sparse forest, and 20% - 30% is close to sparse forest, which is consistent with the results of quantitative experimental simulation analysis. The vegetation index NDVI can detect the growth status, coverage, and eliminate part of the radiation error of vegetation. A value less than 0.4 indicates less vegetation cover or unhealthy vegetation. The enhanced vegetation index (EVI) is an index used in vegetation remote sensing monitoring to reflect the changes in vegetation growth status over time and space, and it is an improvement of NDVI. A value less than 0.3 indicates poor vegetation productivity and health status.

[0008] The inner soil layer and the slag covering layer are comfortable areas for vegetation growth, which create a suitable growth environment for vegetation reconstruction. Among them, the inner soil layer is the suitable growth layer, and the slag covering layer is the potential growth layer. The slag covering layer is stone slag or construction waste soil, and the content of stone slag in the construction waste soil is greater than 30%, and 70% of the particle size of the stone slag does not exceed 10 cm. The bottom of the slag covering layer is the bedrock layer, which provides a to-be-developed environment for the sustainable development of vegetation, including the weathered layer and the unweathered bedrock. The weathered layer is the secondary potential growth layer, which can be broken under the action of long-term biological weathering and other factors to form parent material and soil, and provide the required growth substances for vegetation through the roots of vegetation. The unweathered bedrock is the to-be-developed layer.

[0009] Furthermore, the area of the key restoration area in step 1) , where s is the projected area of the key restoration area, and α is the slope angle of the slope. The fish-scale pits in step 2) are semi-circular or approximately semi-lunar in shape, arranged in a triangular pattern, with a spacing of a. The lowest point of the reverse slope of the surrounding ridge is the overflow outlet. The total number of fish-scale pits set in the key restoration area is , and the maximum water storage capacity of the fish-scale pit is , where r is the opening radius of the fish-scale pit, is the depth of the overflow outlet of the surrounding ridge of the fish-scale pit, is the soil water retention coefficient, and its value range is 0.5 - 0.8. The maximum water retention capacity has practical reference for calculating water retention and other characteristics according to the weather during irrigation and rainy seasons. The number of fish-scale pits is calculated according to the actual area of the slope. According to the latest research by Zhichao Deng (2025) and others, water retention and vegetation-induced changes have positive significance for slope hydrological processes, soil strength, and slope stability.

[0010] The surrounding ridge gradually thins from the center to both ends. The lowest point of the reverse slope of the surrounding ridge is the overflow outlet, and the lowest point is also the thinnest part, which can effectively prevent structural damage and collapse caused by over-storage during heavy rain. The surrounding ridge can achieve the functions of a retaining wall and a sediment retention dam, and filter rainwater, so that the rainwater carries silt and deposits on the surface of the inner soil layer.

[0011] Furthermore, the surrounding ridge of the fish-scale pit in step 2) is made of at least one of dry-laid stone, mortar-laid stone, concrete casting, or ecological bags. When using mortar-laid stone or concrete casting, a drain hole, a diversion groove, a drainage hole, or an overflow weir should be left.

[0012] The land preparation method of the present invention can make the geological environment naturally transition to the soil environment, which is successively the bedrock, the weathered layer of the bedrock, the slag covering layer, and the inner soil layer from bottom to top, overall simulating the natural soil formation process of the bedrock. The weathered layer and the slag covering layer can gradually form soil through long-term weathering effects such as root splitting, and promote the roots to continuously penetrate into the weathered layer and the bedrock layer of the bedrock.

[0013] Furthermore, a bentonite blanket is arranged between the bedrock weathered layer and the slag layer. The bentonite blanket is made of two layers of straw fiber or biodegradable bio-based plastic materials with bentonite sandwiched in the middle. A bentonite blanket is arranged between the bedrock weathered layer and the slag layer of the fractured rock formation. When the bentonite blanket meets water, it can quickly expand to form an impermeable layer and block the downward infiltration and loss of water along the penetrating fissures. The newly weathered soil is composed of weathered soil and unweathered minerals. The unweathered minerals and the weathered soil are filled into the fissures continuously during the long-term soil formation by plants and the degradation process of the bentonite blanket. The unweathered minerals form a framework, and the soil with finer particles fills the gaps in the framework, which can fill and seal the top of the fissures to continue to prevent the retained water from infiltrating and losing downward.

[0014] The inner soil layer and the bund are set to have a reverse slope (reverse gradient, that is, the slope of the soil layer or the bund is opposite to the natural slope direction), which can optimize the soil and water conservation effect.

[0015] Furthermore, the setting of the reverse slope angle of the inner soil layer: 1) For slopes below 40°, a slight reverse slope of 2° - 10° is set to balance water storage and soil stability; 2) For steep slopes above 30° or high rainfall areas, a reverse slope of 8° - 15° is set to enhance the interception capacity; 3) When the reverse slope angle is greater than or equal to 15°, the internal friction force of the soil may be insufficient, and root reinforcement or geogrid needs to be added.

[0016] To resist runoff scouring, a bund is set. The reverse slope angle of the bund can be set as follows: 1) For soil bunds, it is 2° - 45°, with a relatively gentle slope to reduce the risk of side slip; 2) For reinforced bunds (generally made of masonry or ecological bags), it is 10° - 60°. Since rock excavation on rocky slopes can produce rockfill, it is recommended to use the local rockfill for masonry. For steep slope design, it saves space and has anti-scouring ability; 3) In addition, the top width of the bund ≥ 0.2m to maintain the structural stability.

[0017] Setting the inner soil layer to have a reverse slope can take into account water storage and plant growth, which is mainly manifested in: 1) Enhancing the runoff interception capacity, prolonging the infiltration time (rainwater needs to overcome the reverse slope resistance to flow out, promoting the infiltration of water into the deep soil), and reducing runoff overflow (the reverse slope effectively intercepts the slope runoff and reduces the risk of water flow scouring the edge of the pit); 2) Improving soil stability. The reverse slope structure makes the soil pressure of the soil layer and the bund incline inward through the action of gravity, reducing the lateral sliding force. The reverse slope of the bund can disperse the water impact force, reduce the risk of local erosion and the probability of bund collapse, and extend the service life of the fish-scale pit; 3) Promoting vegetation growth and optimizing the microenvironment. The reverse slope structure forms a local low-lying area, increasing the aggregation of soil moisture and nutrients, providing a stable and moist environment for plant roots, reducing soil erosion, protecting seeds and seedlings from being washed away. It has been verified by experiments that the reverse slope design can increase the soil moisture content in the pit by 10% - 20% and improve the vegetation survival rate by more than 30%; 4) Adapting to complex terrains. The reverse slope angle can be adjusted according to the natural slope, applicable to various terrains, combined with the "pyramid-shaped" layout of the fish-scale pits to form a multi-level runoff interception network.

[0018] Furthermore, at least one nodule nitrogen-fixing plant is selected in the vegetation reconstruction described in step 2).

[0019] Furthermore, two tree species of different colors are selected in the vegetation reconstruction described in step 2).

[0020] Vegetation selection and matching follows the principle of adapting to local conditions. According to the characteristics of the biological populations in the implementation area's ecosystem, native dominant arbors, shrubs, and herbaceous plants are planted to reconstruct an ecosystem that is coordinated with the surrounding area. Tree species of different colors can be selected. For example, forsythia with yellow flowers and Amorpha fruticosa with green leaves (the root nodules can maintain soil fertility) can create a beautiful scenery with alternating yellow and green. Grass seeds are sown in the soil-covered area to achieve a combination of two or more plants of arbors, shrubs, and herbs. Combined with the original vegetation, it is more conducive to the construction of a stable micro-ecological environment and the natural growth and succession of vegetation. In addition, when setting fish-scale pits, it is necessary to avoid existing trees with good growth as much as possible and naturally integrate them into the reconstructed vegetation environment.

[0021] Furthermore, drainage grooves are arranged between the fish-scale pits on the slope surface of the key restoration area described in step 2), and a catchment groove and a reservoir are arranged at the bottom of the slope. The drainage grooves are in a shape of an inverted V and are connected along the slope surface, and finally flow into the reservoir through the catchment groove arranged at the bottom of the slope. This technology can realize the collection and utilization of rainwater and is suitable for water supply and irrigation in arid or dry-season areas.

[0022] Furthermore, a slow-release fertilizer layer is provided in the soil layer of the fish-scale pit preparation in the key restoration area described in step 2). The slow-release fertilizer layer is in a concave shape, located above the tree roots, and a water-retaining agent is added. The slow-release fertilizer layer can gradually transfer nutrients to the roots through the infiltration of water, ensuring the nutrient supply during the growth period of the tree species.

[0023] The present invention has the following beneficial effects compared with the prior art: 1. The method of the present invention requires a large amount of creative practical activities from those skilled in the art and is non-obvious. This method can be applied to the fields of ecological restoration, forestry land preparation and afforestation, and soil and water conservation projects according to local conditions. Compared with the prior art, it has significant progress and solves the technical defects raised in the background art. It can produce positive and beneficial effects during the actual application process, taking into account ecological, landscape, and economic benefits, and has obvious practicality.

[0024] 2. The land preparation and vegetation restoration method of the present invention involves constructing a stable and sustainable ecosystem on sloping land. This system includes: 1) the spatial environment, including the geological environment from the underlying and surrounding bedrock to the weathered layer, the slag covering layer, and the possible bentonite blanket set to achieve the transitional environment from rock to soil, and the soil environment with a reverse slope conducive to sediment accumulation; 2) the ecological environment, including the vegetation selection and matching at the landscape level, the combination of trees, shrubs, herbs, and microbial root nodules, etc.; 3) the supporting environment, including the retaining embankment and the drainage and intercepting structure with overflow outlets set as required. The entire stable and sustainable ecosystem on the sloping land integrates natural elements such as water, soil, slag, and rock into the fish-scale pit spatial environment according to local conditions in layers, naturally transitions, and simulates the process of rock weathering to form soil, providing a suitable and sustainable soil environment for vegetation growth.

[0025] 3. The method of the present invention realizes zonal governance, can repair damaged sloping land without over-governance, restores the connectivity of the ecosystem, and has an obvious promoting effect on the creation of biological habitats, the maintenance of ecosystem stability, and the improvement of carbon sequestration capacity. The combined use of the slow-release fertilizer layer and leguminous plants can ensure the nutrients required in the early, middle, and late stages of vegetation growth, reduce the management pressure, improve land productivity, and achieve the sustainability of the greening effect.

[0026] 4. The method of the present invention can effectively affect the hydrological process of the sloping land, including but not limited to resisting runoff scouring, intercepting surface runoff and achieving water storage, reducing soil erosion, coping with extreme precipitation, conserving water, soil, and fertilizer, etc. Finally, it realizes suitable site conditions and creates a beautiful ecological landscape, which has practical significance for the sustainable development of mountainous areas, can boost rural revitalization and the construction of beautiful villages, and is a specific practice and in-depth implementation of ecological civilization and the new development concept.

[0027] 5. The method for preparing the sloping land and restoring vegetation of the present invention is a collaborative innovation of the structure, materials, and functions of sloping land preparation and vegetation restoration. The structure, materials, and functions of each part cooperate and connect with each other to jointly promote the realization of the effects of the present invention. The method of the present invention is fully disclosed and easy to implement, and can be replicated and promoted to similar engineering projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a sectional view and a plan view comparison of the sloping land preparation and vegetation restoration in the key restoration area of the present invention.

[0029] Figure 2 It is a distribution plan view of the key restoration area and the general restoration area of the sloping land in Example 2.

[0030] In the figure: 1 is the key restoration area; 2 is the general restoration area; 11 is the slag covering layer; 111 is the bentonite blanket; 12 is the inner soil layer; 121 is the slow-release fertilizer layer; 13 is the tree species for vegetation reconstruction; 14 is the retaining embankment; 141 is the overflow outlet; 15 is the slope tendency. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The present invention will be further described below in conjunction with two embodiments and the accompanying drawings. During the description process, all technical features and inventive concepts will be covered as much as possible, and the beneficial effects will be briefly analyzed: Embodiment

[0032] In the low mountain and hilly area of the Taihang Mountains in northern Henan, there is little rainfall and the soil is barren. The slope soil is severely scoured during the rainy season, and there is no standing condition for vegetation, and the ecological system is severely degraded and damaged. Patchy rocky desertification has occurred on the slope of a certain historical legacy abandoned mine in this area. In this ecological restoration project, ArcGIS is used to calculate the NDVI of the slope UAV images, and the area with a value less than 0.4 is designated as the key restoration area, and the area with a value greater than 0.4 is designated as the general restoration area. Combining on-site findings, Key Restoration Area 1 is a patch with severe soil erosion and interrupted vegetation continuity, with a slope angle of 18 - 40°.

[0033] For the key restoration area, contour pits are prepared and vegetation is reconstructed. First, contour pits are prepared: A single contour pit is an approximately semi-circular pit with an outer high and inner low reverse slope, arranged in a "pin" shape along the contour line. The average radius of a single contour pit is 0.60 m, and the average depth is 0.60 m; the projected area of the contour pit preparation area is 275.35 m 2 , and the slope area of this area is 291.22 m 2; The horizontal spacing between adjacent fish-scale pits is 2.00 m, and the row spacing in the vertical direction is also 2.00 m. A total of 73 fish-scale pits need to be set. According to the actual situation, topsoil stripping is carried out. In some areas where bedrock is exposed and there is no topsoil, this item can be omitted. The topsoil is stripped to the slope top for convenient backfilling; then rock drilling is carried out, and the rock slag is piled up at the bottom of the slope for convenient construction of the retaining dike 14. The total excavation depth is 0.6 m, of which the average thickness of the surface soil and debris is 0.15 m, and the thickness of the limestone is 0.45 m. Each single fish-scale pit is approximately a semi-cylindrical body; due to the developed fissures on the surface of the limestone during the excavation process, two layers of bentonite blankets 111 composed of straw fiber and bentonite are set at the bottom of the fish-scale pit cavity. Then, slag covering and soil covering are carried out. The thickness of the slag covering layer 11 is 0.15 m, and the thickness of the inner soil layer 12 is 0.35 m. The space of the fish-scale pit is filled with the inner soil layer 12 and the slag covering layer 11 from top to bottom in sequence, and the soil is compacted layer by layer; an arc-shaped retaining dike 14 is built in the downhill direction of the fish-scale pit and set as an anti-slope. The cross-section of the retaining dike 14 is trapezoid-like, with the upper width of 0.20 m, the average lower width of 0.40 m, and the height of 0.30 m. The length of the retaining dike 14 for each single fish-scale pit is about 1.88 m. The thickness of the retaining dike 14 decreases from the center to both ends. The retaining dike 14 is an anti-slope, and the lowest points at both ends are the overflow ports 141. A slow-release fertilizer layer 1211 is provided in the inner soil layer 12. The slow-release fertilizer layer is concave and located above the tree roots. According to the characteristics of the biological populations in the ecosystem of the project implementation area, the tree species 13 for vegetation reconstruction are selected as local dominant arbors and shrubs and are matched with herbaceous plants to reconstruct an ecological system that is coordinated with the surrounding area. In this vegetation reconstruction, Amorpha fruticosa and Forsythia suspensa are selected for inter-planting, and mixed herbaceous plant seeds are sown to create a shrub ecological system that is consistent with the surrounding vegetation environment. A total of 37 Amorpha fruticosa plants and 36 Forsythia suspensa plants are planted in this project. The general restoration area is naturally restored, mainly by sowing mixed seeds. The mixed seeds are the same as those for vegetation reconstruction, with the specifications: mixed grass seeds of wild jujube, Vitex negundo var. heterophylla, and Artemisia argyi.

[0034] This embodiment has repaired the damaged land, provided a long-term suitable growth environment for vegetation, realized the natural evolution of rocks, soil, and vegetation, significantly improved the runoff interception and water and soil conservation, and created a beautiful scenery with yellow and green alternating. In addition, this embodiment has achieved a balance of stone materials, without the need to transport or dispose of stone materials or slag. The Forsythia suspensa used is a kind of medicinal material, and the Amorpha fruticosa is a leguminous plant. Embodiment

[0035] After the overburden repair of an open-pit mined and damaged slope in the southeastern Loess Plateau, the vegetation in the overburden area has developed well but there is a certain degree of soil and water loss phenomenon, and the vegetation in other areas has developed poorly. In this ecological restoration project, ArcGIS is used to calculate the enhanced vegetation index EVI for the slope UAV images, and the areas with EVI less than 0.3 are designated as the key restoration area 1, and the others are the general restoration area 2. Combining on-site findings, the key restoration area 1 is the area where vegetation is underdeveloped or extremely poorly developed, with a slope angle of 19 - 25°, and the general restoration area 2 is the area where vegetation has developed well.

[0036] Approximately semi-circular fish-scale pits are set in the key restoration area 1. First, contour plowing is carried out in a "pin" shape. During construction, pits are dug from the top to the bottom of the slope following the contour. When stripping the topsoil, the fine slag or topsoil dug out is piled up in the uphill direction of the pit for reuse when planting or sowing. When rock drilling, the stones or slag are placed in the downhill direction of the fish-scale pit for subsequent use in building the arc-shaped retaining bank 14. According to the requirements of fish-scale pit plowing, a slag covering layer 11 and an inner soil layer 12 are filled, and the inner soil layer 12 is set as an inverse slope. The inner soil layer 12 is provided with a slow-release fertilizer layer 121, and the slow-release fertilizer layer 121 is concave and located above the tree roots, which can slowly bring nutrients to the roots along with seepage water. At the downhill edge of the fish-scale pit, the retaining bank 14 is built using the crushed stones produced by rock drilling on-site or other suitable materials and is set with an inverse slope to enhance its water storage and soil retaining capacity. The tree species 13 for vegetation restoration are selected as wild jujube and vitex negundo var. heterophylla, and wormwood seeds are sown to blend in with the surrounding vegetation. The general restoration area 2 is naturally restored, mainly by sowing wormwood seeds on the surface with Quaternary sedimentary layers. The retaining bank 14 uses dry-laid stones at slopes with an angle less than 30°, and uses mortar-laid stones at slopes with an angle greater than 30°. The mortar-laid stone retaining bank is provided with an overflow weir, and a notch similar to that of a check dam is convenient for discharging excess precipitation. Drainage troughs are set on the slopes in areas with a large catchment area, and a catchment trough and a reservoir are set at the bottom of the slope. The drainage troughs are in an inverted V shape and are connected along the slope, and finally flow into the reservoir through the catchment trough set at the bottom of the slope.

[0037] This embodiment can effectively repair the problems of soil and water loss and poor development of slope vegetation, improve the runoff interception efficiency and the vegetation coverage rate in the pits, and store water to provide water sources for the dry season. Compared with the soil-covered area, it has a lower cost, requires less imported soil, and the stone materials can be used on-site, realizing the transition environment from rock to soil. It can discharge excess precipitation during over-storage, and integrates natural elements such as water, soil, slag, and rock into the fish-scale pit space environment in a stratified manner according to local conditions, with a natural transition and simulating the process of rock weathering and soil formation, providing a suitable and sustainable soil environment for vegetation growth. It can produce positive and beneficial effects in the actual application process and has practicality.

Claims

1. A method for slope land preparation and vegetation restoration, characterized in that: The slope is a rocky slope with a slope angle greater than 15°. The land preparation and vegetation restoration methods include Step 1) Divide the slope into a key restoration area and a general restoration area according to one of the canopy density, normalized difference vegetation index (NDVI), or enhanced vegetation index (EVI); Step 2) Conduct fish-scale pit land preparation and vegetation reconstruction in the key restoration area. The fish-scale pit land preparation includes topsoil stripping, rock drilling, slag covering, soil covering, and ridge building. The fish-scale pit space formed by topsoil stripping and rock drilling is filled with inner soil layer and slag covering layer from top to bottom in sequence. When there is no topsoil, only rock drilling is carried out. The inner soil layer and the ridge are set as reverse slopes. The vegetation reconstruction includes at least one of arbors and shrubs and herbaceous plants; Step 3) Conduct natural restoration in the general restoration area. The main measures include at least one of site closure, sign setting, replanting, reseeding, and tending. The vegetation selected for replanting or reseeding includes at least one of arbors, shrubs, and herbaceous plants.

2. The method for sloping land preparation and vegetation restoration according to claim 1, characterized in that: In Step 1), the area with a canopy density less than 30%, a normalized difference vegetation index (NDVI) less than 0.4, or an enhanced vegetation index (EVI) less than 0.3 is taken as the key restoration area, and the rest is taken as the general restoration area.

3. The method for slope land preparation and vegetation restoration according to claim 1 or 2, characterized in that: Step 1) the area of the key repair area , where s is the projected area of the key repair area, α is the slope angle of the slope. In step 2), the fish-scale pits are arranged in a pyramid shape with a spacing of a, and the lowest point of the surrounding ridge with an inverted slope is the overflow outlet. The total number of fish-scale pits set in the key repair area is , and the maximum water storage capacity of the fish-scale pit is , where r is the opening radius of the fish-scale pit, is the depth of the overflow outlet of the fish-scale pit surrounding ridge, is the soil water retention coefficient, and its value range is 0.5 - 0.

8.

4. The method for sloping land soil preparation and vegetation restoration according to claim 1 or 2, characterized in that: The fish-scale pit ridge in Step 2) is made of at least one of dry-laid stone, grouted stone, concrete casting, or ecological bags. When using grouted stone or concrete casting, at least one of drain holes, diversion channels, drainage holes, or overflow weirs is reserved.

5. The method for slope land preparation and vegetation restoration according to claim 1 or 2, characterized in that: A bentonite blanket is set between the bedrock weathered layer and the slag layer. The bentonite blanket is made of two layers of straw fiber or biodegradable materials of bio-based plastics, with bentonite sandwiched in the middle.

6. The method for slope land preparation and vegetation restoration according to claim 1 or 2, characterized in that: Setting of the reverse slope angle of the inner soil layer: For slopes below 40°, a slight reverse slope of 2° - 10° is set; for steep slopes above 30°, a reverse slope of 8° - 15° is set. When the reverse slope angle is greater than or equal to 15°, root reinforcement or geogrid is added.

7. The method for sloping land soil preparation and vegetation restoration according to claim 1 or 2, characterized in that: At least one legume plant for nitrogen fixation is selected in the vegetation reconstruction in Step 2).

8. The method for slope land preparation and vegetation restoration according to claim 1 or 2, characterized in that: Two tree species of different colors are selected in the vegetation reconstruction in Step 2).

9. The method for sloping land preparation and vegetation restoration according to claim 1 or 2, characterized in that: In the key restoration area in Step 2), drainage grooves are set between the fish-scale pits on the slope surface, and a catchment groove and a reservoir are set at the bottom of the slope. The drainage grooves are in a V shape and are connected along the slope surface, and finally flow into the reservoir through the catchment groove set at the bottom of the slope.

10. The method for sloping land preparation and vegetation restoration according to claim 1 or 2, characterized in that: A slow-release fertilizer layer is provided in the inner soil layer of the fish-scale pit land preparation in the key restoration area in Step 2). The slow-release fertilizer layer is concave and is located above the tree roots.

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