Ecological restoration method and system for high and steep road slope with serious water and soil loss

Abstract

The invention discloses an ecological restoration method and system for a high and steep road slope with serious water and soil loss. The method comprises the steps that biological straw bundles are embedded and inserted into a soil body in a slope frame; the interior of the side slope frame is divided into a plurality of square areas with the same area, every two adjacent square areas are separated through plant separation materials, each square area is fully paved with vegetation bags, and the vegetation bags and the soil body are fixed together through fixing pieces; the slope is covered with a plant mat, and the edge of the plant mat and the soil body are fixed together through a fixing piece. The system comprises side slope lattices, biological straw bundles, plant separation materials, plant growing bags and plant pads. Spatial coupling is formed through the four-stage structure of embedding, separating, filling and covering, the four-stage structure transmits layer by layer and supports each other, rainstorm scouring energy is weakened step by step in the slope surface, and therefore the slope body is stabilized, erosion is restrained, and rapid planting of vegetation is promoted.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of ecological restoration, and particularly relates to an ecological restoration method and system for a high and steep highway slope with serious soil erosion. BACKGROUND

[0002] Soil erosion refers to the destruction and loss of water and soil resources and land productivity under the action of natural forces such as water, wind, gravity and freeze-thaw, and human activities, including land surface erosion and water loss. At present, with the change of ecological environment, soil erosion also occurs and intensifies.

[0003] In water conservancy construction, a large number of slopes often need to be excavated, and the development of the slope seriously destroys the original vegetation cover layer, causing ecological environmental problems such as desertification, soil erosion, landslides and mudslides. In the prior art, the treatment of steep rock slopes mostly adopts single engineering protection (such as shotcrete and anchor rod support), which has the problems of high cost and poor ecological compatibility; and the survival rate of pure vegetation restoration technology is insufficient under strong acid (pH < 4) and high scouring conditions. In addition, acid mine drainage (AMD) caused by sulfide ore oxidation further aggravates soil degradation. Although the co-pyrolysis product can improve the soil properties, there is a lack of systematic application research on strong acid slopes.

[0004] Therefore, it is necessary to develop an ecological restoration method and system for a high and steep highway slope with serious soil erosion, which can reduce soil erosion and repair difficulty. SUMMARY

[0005] In view of the problems of difficult generation of slope repair plants and serious soil erosion caused by lack of soil and barrenness on the highway rock barren slope, the first object of the present application is to provide an ecological restoration method for a high and steep highway slope with serious soil erosion, which realizes the ecological restoration of the slope by composting improvement combined with biomass blocking technology.

[0006] The second object of the present application is to provide a system for realizing the ecological restoration method of the high and steep highway slope with serious soil erosion.

[0007] The first object of the present application is achieved by the following steps: S1, inserting a bundle of biological straw into the soil in the slope frame; S2, dividing the slope frame into a plurality of square areas with equal areas, and separating adjacent square areas by plant separation material, and covering each square area with a planting bag, and fixing the planting bag and the soil together by a fixing member; S3, covering the slope with a plant mat, and fixing the edge of the plant mat and the soil together by a fixing member.

[0008] The side slope frame is a prefabricated frame commonly used in the field of side slope, and the shape thereof can be square, and the plant mat can be woven by palm fiber or straw.

[0009] Preferably, the biological straw bundle in the S1 step is rice straw or wheat straw, and the rice straw or wheat straw is bundled and soaked in lime water or microbial liquid for 12-24 hours to enhance the preservation and root promotion performance.

[0010] Preferably, the biological straw bundle in the S1 step is inserted at a vertical angle or an angle of 5-10 degrees to the slope surface.

[0011] Preferably, the plant separation material in the S2 step is straw, branch or wood strip.

[0012] Preferably, the plant bag in the S2 step is filled with compost improved soil and drought-tolerant grass seeds, and the amount of drought-tolerant grass seeds is 3% of the weight of the compost improved soil.

[0013] Preferably, the drought-tolerant grass seeds are one or more of artemisia, imperata cylindrica, ptychosperma, polygonum capitatum, polygonum perfoliatum and eriochloa.

[0014] Preferably, the adjacent plant mats are overlapped in the S3 step, and the overlapping width is greater than or equal to 10 cm to enhance the covering capacity.

[0015] Preferably, the plant mat is laid on the anti-scouring net to enhance the initial anti-scouring capacity, and the anti-scouring net is degradable non-woven fabric or coconut fiber net.

[0016] The second object of the application is achieved by comprising a side slope frame, a biological straw bundle, a plant separation material, a plant bag and a plant mat, the side slope frame is arranged on the side slope, the biological straw bundle is embedded in the soil in the side slope frame, the plant separation material is arranged in the side slope frame to divide the side slope frame into a plurality of square areas with equal areas, the plant bag is laid in the square area, the first fixing member fixes the plant bag and the soil together, and the plant mat is laid on the side slope, and the second fixing member fixes the edge of the plant mat and the soil together.

[0017] Preferably, the first fixing member and the second fixing member are anchored by steel pegs.

[0018] Preferably, a water collecting groove is arranged along the slope width direction at the ground of the slope toe, the water collecting groove is connected with the measuring cylinder through a flow guide pipe to form a slope surface runoff monitoring device, and the runoff and sediment concentration are recorded regularly.

[0019] The beneficial effects of the present application: the present application forms a space coupling through a four-level structure of "insertion-separation-filling-covering", the vertically inserted biological straw bundles interlock with the soil body in the shallow layer, forming a three-dimensional reinforced framework, which bears the shear deformation in advance; the micro-plant separation divides the slope surface into different catchment units, guiding the runoff to disperse and infiltrate, and at the same time helping to prevent the plant growth bag from sliding; the plant growth bag contains compost improved soil, providing alkaline buffer and continuous nutrients, and after the subsequent plants germinate and root, an anti-erosion system is formed by the integration of the root system, the bag soil and the plant growth bag itself; the outermost plant mat converts the kinetic energy of raindrops into pore water pressure dissipation and locks the surface water, and can also cooperate with the anti-scouring net to further enhance the water locking effect; the four-level structure of the present application transmits and supports each other layer by layer, realizing the synchronous action of "framework reinforcement-runoff dispersion-matrix improvement-surface energy dissipation", so that the rainstorm erosion energy is gradually weakened in the slope surface, thereby stabilizing the slope body, inhibiting erosion and promoting rapid planting of vegetation. BRIEF DESCRIPTION OF DRAWINGS

[0020] Fig. 1 is a schematic diagram of the slope profile structure of the present application; Fig. 2 is a schematic diagram of the planar structure of the slope frame without covering the plant mat; In the figure: 1-slope frame, 2-biological straw bundle, 3-plant separation material, 4-plant growth bag, 5-plant mat, 6-anti-scouring net, 7-first fixing part, 8-second fixing part, 9-catchment tank, 10-flow guide pipe, 11-measuring cylinder. DETAILED DESCRIPTION

[0021] The present application will be further described below in conjunction with the embodiments and the drawings, but in no way limits the present application, any transformation or replacement based on the teaching of the present application belongs to the protection scope of the present application.

[0022] Example 1 A high and steep red soil highway slope (slope height 25 m, slope 55°) with serious water and soil loss; as shown in the accompanying Figs. 1-2 The ecological restoration method for the high and steep water and soil loss highway slope according to the present embodiment is used to treat the slope, including the following steps: S1, bundle the rice straw, diameter 8 cm, length 40 cm, soak the biological straw bundle 2 in lime water, soak for 24 h, then dry, to obtain the biological straw bundle 2; remove the floatstone, weeds and loose soil layer, and level the slope surface; insert the biological straw bundle 2 into the soil in the slope frame 1 according to a 1 m x 1 m grid, the biological straw bundle 2 completely enters the soil, and the insertion angle of the biological straw bundle 2 is 7.5° inclined to the slope surface from the vertical as the starting point; S2, divide the slope frame into several 0.5 m x 0.5 m square regions, separate adjacent square regions with branches, and each square region is covered with a vegetation bag 4, the vegetation bag 4 contains compost modified soil (compost modified soil is obtained by mixing red soil and mature straw biochar at a mass ratio of 7:3) and drought-tolerant grass seeds (mixture of artemisia and miscanthus at a mass ratio of 1:1), the amount of drought-tolerant grass seeds is 3% of the weight of the compost modified soil, and a steel drill is used to punch into the slope surface at a grid of 1 m x 1 m to a depth of 80-100 cm, the vegetation bag 4 is fixed together with the soil body; S3, lay the anti-erosion net 6 (use degradable non-woven fabric) on the slope, then cover the plant mat 5, the plant mat 5 is a palm fiber mat, the adjacent plant mats 5 are overlapped, the overlapping width is 10 cm, and the edges of the plant mat 5 are fixed together with the soil body by a U-shaped steel drill; Through monitoring, the average runoff is reduced from 1.8 L / min to 0.4 L / min, the sediment concentration is reduced from 12 g / L to 1.5 g / L, and the vegetation coverage is 82% within 30 days.

[0023] Example 2 A certain highway slope is a karst gravel slope (slope height 18 m, slope 60°), with serious water and soil loss; the ecological restoration method of the high and steep highway slope with serious water and soil loss in this embodiment is based on example 1, and the difference from example 1 is: In step S1, the biological straw bundle 2 uses wheat straw, the diameter of the biological straw bundle 2 is 6 cm, the length is 38 cm, and the soaking treatment uses bacillus pasteurii liquid (OD600=1.2) for soaking; the embedded biological straw bundle 2 is at a grid of 1.2 m x 1.2 m, and the insertion angle is 5° inclined to the slope surface from the vertical as the starting point; In step S2, adjacent square regions are separated by wooden strips; the compost modified soil is obtained by mixing tailings modified substrate and residue at a mass ratio of 8:2; the drought-tolerant grass seeds are obtained by mixing polygonum capitatum and polygonum orientale at a mass ratio of 1:1; In step S3, the anti-erosion net 6 is selected from coconut fiber net, and the plant mat 5 is a straw mat, and the overlapping width is 12 cm; Rainy season monitoring shows that the erosion rate is reduced from 89.5% for the untreated to 6.3% for the microorganism reinforced, the grass seed germination rate is 78%, and the slope stability coefficient is increased by 1.35 times.

[0024] Example 3 A certain highway slope is a purple soil high slope (slope height 30 m, slope 50°), with serious water and soil loss; the ecological restoration method of the high and steep highway slope with serious water and soil loss in this embodiment is based on example 1, and the difference from example 1 is: In step S1, the soaking treatment involves soaking in lime water with pH 10 and 0.5% humic acid for 12 hours; the embedded biological straw bundles 2 are arranged in a 1.5m × 1.5m grid, with the insertion angle starting from the vertical and tilted 10° towards the slope. In step S2, adjacent square areas are separated by straw; the compost-improved soil is obtained by mixing tailings modified substrate and bacterial residue in a mass ratio of 7:3; the barren-tolerant grass seed is goosegrass; In step S3, the erosion-resistant mesh 6 is made of coconut fiber mesh; After 180 days, the vegetation coverage reached 90%, the slope erosion was reduced by 92%, and the soil organic matter increased by 1.8 times.

[0025] Example 4 The ecological restoration method for steep, severely eroded highway slopes in this embodiment is based on Embodiment 1, but differs from Embodiment 1 in that: In step S1, soak for 18 hours; insert the biological straw bundle 2 at an angle perpendicular to the slope. In step S2, the square area is 0.6m × 0.6m; the barren-tolerant grass seeds are obtained by mixing Artemisia, Imperata, and Lysimachia in a mass ratio of 1:1:1.

[0026] Example 5 This embodiment is a system for implementing the ecological restoration method for steep, severely eroded highway slopes in Embodiment 1. It includes a slope frame 1, biological straw bundles 2, plant separators 3, vegetation bags 4, and plant mats 5. The slope frame 1 is placed on the slope. The biological straw bundles 2 are embedded in the soil within the slope frame 1. The plant separators 3 are placed within the slope frame 1, dividing it into several square areas of equal size. The vegetation bags 4 are laid within the square areas, and a first fixing member 7 secures the vegetation bags 4 to the soil. The plant mats 5 are laid on the slope, and a second fixing member 8 secures the edges of the plant mats 5 to the soil. A water collection trough 9, 30cm wide and trapezoidal in shape, is set along the slope width at the slope toe. The water collection trough 9 is connected to a 500ml measuring cylinder 11 via a guide pipe 10.

Claims

1. An ecological restoration method for steep highway slopes with severe soil erosion, characterized in that... Includes the following steps: S1, biological straw bundles (2) are embedded in the soil within the slope frame (1); S2. Divide the slope frame into several square areas of equal area. Separate adjacent square areas with plant separation material (3). Cover each square area with planting bags (4) and fix the planting bags (4) to the soil with fasteners. S3. Cover the slope with a plant mat (5) and fix the edges of the plant mat (5) to the soil with fasteners.

2. The ecological restoration method for steep highway slopes with severe soil erosion according to claim 1, characterized in that... S1 Step: Biological straw bundle (2) is rice straw or wheat straw. The rice straw or wheat straw is bundled into bundles and treated with lime water or microbial liquid. After that, it is dried. The soaking time is 12h~24h.

3. The ecological restoration method for steep highway slopes with severe soil erosion according to claim 1, characterized in that... S1 Step: Insert the biological straw bundle (2) at an angle perpendicular to the slope or inclined to the slope at 5°~10°.

4. The ecological restoration method for steep highway slopes with severe soil erosion according to claim 1, characterized in that... The plant separation material (3) in step S2 is straw, branches or wooden strips.

5. The ecological restoration method for steep highway slopes with severe soil erosion according to claim 1, characterized in that... The S2 step planting bag (4) contains compost-improved soil and barren grass seeds. The amount of barren grass seeds is 3% of the weight of the compost-improved soil.

6. The ecological restoration method for steep highway slopes with severe soil erosion according to claim 5, characterized in that... The aforementioned barren-tolerant grass seeds are one or more of the following: Artemisia, Imperata, Lysimachia, Polygonum capitatum, Polygonum hydropiper, and Eleusine indica.

7. The ecological restoration method for steep highway slopes with severe soil erosion according to claim 1, characterized in that... In step S3, the adjacent plant pads (5) overlap, with an overlap width ≥ 10cm.

8. The ecological restoration method for steep highway slopes with severe soil erosion according to claim 1, characterized in that... An anti-erosion net (6) is laid under the plant mat (5), and the anti-erosion net (6) is a biodegradable non-woven fabric or coconut fiber net.

9. A system for implementing the ecological restoration method for steep, severely eroded highway slopes according to any one of claims 1 to 8, characterized in that... The system includes a slope frame (1), a bundle of biological straw (2), a plant separator (3), a planting bag (4), and a plant mat (5). The slope frame (1) is set on the slope. The bundle of biological straw (2) is embedded in the soil inside the slope frame (1). The plant separator (3) is set inside the slope frame (1) to divide the slope frame (1) into several square areas of equal area. The planting bag (4) is laid in the square area. The first fixing member (7) fixes the planting bag (4) to the soil. The plant mat (5) is laid on the slope. The second fixing member (8) fixes the edge of the plant mat (5) to the soil.

10. The system according to claim 9, characterized in that... A water collection trough (9) is set on the ground at the toe of the slope along the width of the slope. The water collection trough (9) is connected to the measuring cylinder (11) through the guide pipe (10).

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