A soilless spraying substrate and its preparation method and application

Abstract

The present invention provides a soilless spraying substrate and its preparation method and application, which relate to the field of vegetation restoration technology. The various raw materials of the soilless spraying substrate of the present invention are easy to obtain, simple in structure, easy to configure, low in cost, simple in construction, and good in water absorption and fertilizer retention. It can quickly meet the growth requirements of plants on sandy slopes and promote the ecological restoration of vegetation on sandy slopes. Experiments have shown that the soilless spraying substrate has a wide range of applications, strong resistance to erosion and soil erosion, and rapid growth of slope plants. It is particularly suitable for sandy high and steep slopes with an angle of 25 degrees to 60 degrees and a slope length of 5 to 20 meters. It enables the sandy high and steep slopes to quickly form biological communities, improves the slope's resistance to scour and soil erosion, and can achieve the coordinated development of ecological environment governance and resource development and utilization in ecologically fragile areas.

Description

Technical Field

[0001] The present invention relates to the technical field of vegetation restoration, and in particular to a soilless spraying substrate and a preparation method and application thereof. Background Art

[0002] Northern Shaanxi is arid and rainless, with concentrated rainfall and high evaporation, resulting in a fragile ecological environment and severe soil erosion. Scientifically and effectively managing soil erosion in this region is crucial for the success of ecological civilization development in the Yellow River Basin. This region primarily encompasses aeolian sandy slopes, rock slopes, and loess slopes along the Yellow River. Currently, most loam-like seeding substrates in China are targeted at rocky and loess slopes, sand dunes, and aeolian sandy soils. However, research on ecological restoration of steep sandy slopes is limited.

[0003] There are a large number of arsenic sandstone and aeolian sandy soil (of which the medium sand content is about 95.31%) distributed in northern Shaanxi. Both are extremely harmful to the environment and agricultural production. However, arsenic sandstone has good water retention and aeolian sandy soil has strong permeability. Combining the two is not only conducive to solving local ecological and environmental problems, but also can improve land productivity and increase economic benefits.

[0004] In Heyang and Hancheng areas on the west bank of the Yellow River and the Maowusu Desert area in Shenmu, high and steep sandy slopes are widely distributed, mainly including river alluvial and aeolian sandy steep slopes, aeolian sandy soil, low organic matter content in the soil, poor water and fertilizer retention effect of sandy soil, and small interaction force between particles of desertified soil. The texture is loose, the soil has good air permeability, large porosity, poor water retention, weak water storage capacity, easy loss of water and nutrients, serious soil and water loss, low survival rate of slope vegetation, and slow growth, which seriously affects the construction and restoration of the ecological landscape on both sides of the middle reaches of the Yellow River. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a soilless spraying substrate, which for the first time incorporates arsenic sandstone and aeolian sand into the spraying substrate for slope ecological restoration, which can quickly repair damaged slopes and has a good greening effect.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] The present invention provides a soilless spraying substrate, which comprises the following raw materials in parts by weight:

[0008] 30-40 parts of arsenic sandstone and sandy soil, 25-30 parts of plant fiber, 0.5-1.0 part of soil water-retaining agent, 0.5-1.0 part of binder, 0.5-1.0 part of polyglutamic acid microbial agent, 5-10 parts of rice husks, and 5-15 parts of fertilizer; the ratio of the arsenic sandstone to the sandy soil is 1:2-1:5; the particle size of the arsenic sandstone and sandy soil is ≤2mm.

[0009] Preferably, the plant fibers include wood fibers and / or grass fibers.

[0010] Preferably, the soil water-retaining agent includes any one of acrylamide-acrylate copolymer cross-linked product, starch-acrylate graft copolymer cross-linked product, potassium polyacrylate, and polyacrylamide.

[0011] Preferably, the binder is anionic polyacrylamide or starch-modified acrylic acid-acrylamide copolymer resin.

[0012] Preferably, the polyglutamic acid microbial agent is compounded by functional microorganisms and polyglutamic acid, wherein the functional microorganisms include Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus mucilaginosus, and Trichoderma harzianum; and the effective viable count of the polyglutamic acid microbial agent is ≥2 billion / ml.

[0013] Preferably, the fertilizer includes organic fertilizer and / or inorganic fertilizer.

[0014] The present invention also provides a method for preparing the soilless spraying substrate, which comprises the following steps:

[0015] The soilless spraying substrate is obtained by sequentially mixing water, fertilizer, soil water retaining agent, adhesive, polyglutamic acid microbial agent, plant fiber, rice husk, arsenic sandstone and aeolian sand soil, and fully dissolving them.

[0016] The present invention also provides a method for ecological restoration of arid, steep, sandy slopes, comprising the following steps:

[0017] After the sandy slope is renovated, planting holes are drilled, the substrate is added to the planting holes, and shrub seedlings are inserted;

[0018] The mixed mud is sprayed onto the surface of the sandy slope as a solidification layer, and then the above-mentioned base material and grass seeds are mixed and sprayed onto the surface of the solidification layer.

[0019] Preferably, the mixed mud includes the following components in percentage by weight: 35%-60% clean water, 0.5%-1.5% water retaining agent, 0.5%-2% adhesive, 10%-20% fertilizer, 10%-30% arsenic sandstone, and 5%-15% sandy soil.

[0020] Preferably, the thickness of the solidified layer is 1-3 cm, and the thickness of the substrate and grass seeds after spraying is 2-8 cm.

[0021] Compared with the prior art, the present invention has the following technical effects:

[0022] The present invention provides a soilless spraying substrate, its preparation method, and its application. The soilless spraying substrate is made from readily available raw materials, has a simple structure, is easy to configure, is low-cost, and is simple to construct. It also has excellent water absorption and fertilizer retention capabilities, quickly meeting plant growth requirements on sandy slopes and promoting ecological restoration of vegetation on these slopes. Furthermore, the present invention is the first to incorporate arsenic sandstone and aeolian sandy soil into the spraying substrate for slope ecological restoration, fully utilizing the local "environmental cancer" arsenic sandstone, transforming "two pests" into "one treasure," addressing the problems of soillessness, soil shortage, and soil scarcity in local engineering projects.

[0023] Tests have shown that the soilless spraying substrate of the present invention has a wide range of applications, strong resistance to erosion and soil erosion, and rapid growth of slope plants. It is particularly suitable for sandy high and steep slopes with a slope of 25 to 60 degrees and a slope length of 5 to 20 meters. It enables the rapid formation of biological communities on sandy high and steep slopes, improves the slope's resistance to erosion and soil erosion, and can achieve coordinated development of ecological environment management and resource development and utilization in ecologically fragile areas. DETAILED DESCRIPTION

[0024] The present invention provides a soilless spraying substrate, which comprises the following raw materials in parts by weight:

[0025] 30-40 parts of arsenic sandstone and sandy soil, 25-30 parts of plant fiber, 0.5-1.0 part of soil water-retaining agent, 0.5-1.0 part of binder, 0.5-1.0 part of polyglutamic acid microbial agent, 5-10 parts of rice husks, and 5-15 parts of fertilizer; the weight ratio of the arsenic sandstone and sandy soil is 1:2-1:5; the particle size of the arsenic sandstone and sandy soil is ≤2mm.

[0026] In the present invention, the arsenic sandstone and aeolian sandy soil are preferably naturally air-dried arsenic sandstone and aeolian sandy soil; the weight ratio of the arsenic sandstone and aeolian sandy soil is preferably 32-38 parts, more preferably 35-36 parts; and the ratio of the arsenic sandstone to aeolian sandy soil is preferably 1:3-1:4. In the present invention, the arsenic sandstone contains up to 16.8%-46.4% secondary clay minerals and more than 10% clay particles, which can complement the aeolian sandy soil, providing the core material (colloid) for sandy soil formation, compensating for particle size defects, and forming a new type of soil with better texture.

[0027] In the present invention, the plant fiber preferably includes wood fiber and / or grass fiber; the weight portion of the plant fiber is preferably 28-29 parts. The plant fiber of the present invention mainly plays the role of retaining water, retaining fertilizer and strengthening the connection between loam-like matrix particles, and has the effects of improving the shear strength of the substrate, delaying the time for shrinkage to produce cracks, reducing the width of the cracks and reducing erosion and sand production, so that the overall stability of the substrate can be maintained well. In the present invention, the wood fiber is preferably extracted by a high-temperature and high-pressure detonation method to extract the fiber production process; the organic matter content in the wood fiber is preferably ≥95%, the moisture content is preferably 12%-18%, the water absorption rate is preferably 1600%, and the biodegradability is preferably 100%; the average length of the plant fiber is preferably 2mm-10mm, more preferably 5-8mm.

[0028] In the present invention, the soil water-retaining agent preferably includes any one of acrylamide-acrylate copolymer cross-linked product, starch-acrylate graft copolymer cross-linked product, potassium polyacrylate, and polyacrylamide; the weight portion of the soil water-retaining agent is preferably 0.7-0.8 parts. In the present invention, the soil water-retaining agent mainly plays the role of retaining water, fertilizer, heat preservation, soil conservation, improving soil structure and drought resistance, and has the comprehensive function of regulating soil water and fertilizer, alleviating and coordinating soil water and fertilizer shortages, and maintaining and improving the effectiveness of water and nutrients in the soil. High water absorption cross-linked potassium polyacrylate type soil water-retaining agent can significantly increase the water storage capacity of sandy soil, so that the soil contains more effective water that can be used for plant growth, and can delay the time when crops wither due to strong water evaporation. The formation of soil aggregate structure is conducive to increasing soil permeability, reducing surface runoff and forming an anti-water erosion protective layer in the soil, thereby effectively preventing soil and water loss.

[0029] In the present invention, the binder is preferably anionic polyacrylamide or a starch-modified acrylic acid-acrylamide copolymer resin; the anionic polyacrylamide is preferably PAMA30 or PAM-2120. The binder is preferably present in an amount of 0.7-0.8 parts by weight. In the present invention, the binder can cause aeolian sand particles to adsorb and bond to each other, forming an aggregate structure.

[0030] In the present invention, the polyglutamic acid microbial agent is preferably composed of a compound of functional microorganisms and polyglutamic acid. The functional microorganisms preferably include Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus mucilaginosus, and Trichoderma harzianum. The effective viable count of the polyglutamic acid microbial agent is preferably ≥ 2 billion / ml. The weight portion of the polyglutamic acid microbial agent is preferably 0.7-0.8 parts. In the present invention, the polyglutamic acid microbial agent can significantly enhance microbial activity and promote synergistic effects between microorganisms. It has the effects of retaining water, promoting plant root growth, enhancing plant resistance, improving fertilizer utilization, improving soil aggregate structure, regulating soil pH, and alleviating soil compaction.

[0031] In the present invention, the fertilizer preferably includes organic fertilizer and / or inorganic fertilizer; the weight of the fertilizer is preferably 10-12 parts. The fertilizer of the present invention primarily provides nutrients for plant development and growth, improves soil structure, and maintains long-term fertilizer efficacy. In the present invention, the weight of the rice husk is preferably 6-8 parts; rice husk is inexpensive and can increase the organic matter content of the spraying substrate, improving fertility and aeration, preventing compaction, improving physical structure, and maintaining long-term fertilizer efficacy.

[0032] The present invention provides a method for preparing the soilless spraying substrate, comprising the steps of sequentially mixing water, fertilizer, a soil water-retaining agent, an adhesive, a polyglutamic acid microbial agent, plant fiber, rice husks, arsenic sandstone, and aeolian sandy soil, and obtaining the soilless spraying substrate after sufficient dissolution. The present invention has no particular requirements for the amount of water added; the amount sufficient to ensure sufficient dissolution of all raw materials is sufficient.

[0033] The present invention also provides a method for ecological restoration of arid, steep, sandy slopes, comprising the following steps:

[0034] After the sandy slope is renovated, planting holes are drilled, the substrate is added to the planting holes, and shrub seedlings are inserted;

[0035] The mixed mud is sprayed onto the surface of the sandy slope as a solidification layer, and then the above-mentioned base material and grass seeds are mixed and sprayed onto the surface of the solidification layer.

[0036] In the present invention, the said remediation preferably includes: cleaning dangerous sand and soil to eliminate safety hazards; in local high sections, graded slow-down slope, building steps, each step height not exceeding 20 meters, width not less than 1 meter. In the present invention, the diameter of the said planting hole is preferably 10cm-20cm, the depth is preferably 20cm-40cm, and the density is preferably 1-4 / m 2 The spacing between the planting holes is preferably 40-100 cm, arranged in a plum blossom pattern. The present invention improves the long-term effectiveness of restoration by setting up planting holes and planting shrubs in combination with grass seeds. The shrub seedlings are preferably one or more of Amorpha fruticosa, Lespedeza bicolor, and Vitex truncatum.

[0037] The present invention sprays a mixed slurry onto the surface of a sandy slope to form a solidifying layer. The mixed slurry preferably comprises the following components by weight: 35%-60% water, 0.5%-1.5% water-retaining agent, 0.5%-2% binder, 10%-20% fertilizer, 10%-30% arsenic sandstone, and 5%-15% aeolian sand. The solidifying layer preferably has a thickness of 1-3 cm. The solidifying layer forms a stable, integrated structure, which not only enhances the slope's stability and resistance to wind and water erosion, but also facilitates the adhesion of the sprayed thin layer of loam-like substrate and reduces the loss of moisture and nutrients from the slope surface to the lower layers. Furthermore, it facilitates the subsequent spraying of a mixture of substrate and grass seed, preventing the problem of substrate splashing and serious losses during grass seed spraying.

[0038] The present invention sprays the mixture of the substrate and grass seeds onto the surface of the solidified layer; the thickness of the mixture of the substrate and grass seeds is preferably 2-8 cm, more preferably 5-6 cm. In the present invention, the spraying is preferably carried out using a sprayer. The grass seeds of the present invention preferably include one or more of: Amorpha fruticosa, tall fescue, Gesanghua, sand reed, sea buckthorn, Achnatherum splendens, Ailanthus altissima, Amorpha fruticosa, Medicago sativa, Lespedeza bicolor, ryegrass, and Bermuda grass. The present invention has no special requirements for the amount of grass seeds added, as long as it can meet the greening requirements.

[0039] After the spray seeding of the present invention is completed, maintenance is preferably included, and the maintenance preferably includes: keeping the construction surface moist, and covering the slope surface with straw, grass mat or film according to the actual situation on site; the maintenance can reduce water evaporation to facilitate plant emergence.

[0040] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0041] In the following examples, unless otherwise specified, all methods are conventional.

[0042] Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

[0043] In a specific embodiment of the present invention, soil water-retaining agent and binder were purchased from Qingdao Shouke New Materials Co., Ltd.; polyglutamic acid microbial agent was purchased from Yangling Future Zhongke Environmental Protection Technology Co., Ltd.

[0044] Example 1

[0045] A soilless spraying substrate, comprising:

[0046] 3kg of arsenic sandstone and sandy soil, 2.5kg of wood fiber, 0.05kg of potassium polyacrylate, 0.05kg of polyacrylamide, 0.05kg of polyglutamic acid microbial agent, 0.5kg of rice husk, 0.3kg of organic fertilizer, 0.1kg of compound fertilizer, and 0.1kg of water-soluble fertilizer; the ratio of the arsenic sandstone to the sandy soil is 1:2; the particle size of the arsenic sandstone and sandy soil is 2mm;

[0047] Wood fiber is produced by high-temperature and high-pressure detonation extraction process, with an organic matter content of ≥95%, a moisture content of 12%-18%, a water absorption rate of 1600%, and a biodegradability of 100%; the average fiber length is 2mm;

[0048] The organic matter content of water-soluble fertilizer is ≥50g / L, the easily oxidizable organic matter content is ≥40g / L, and the pH value (1:250 dilution) is 2.0;

[0049] Mix arsenic sandstone with 3kg of sandy soil, 2.5kg of wood fiber, 0.05kg of potassium polyacrylate, 0.05kg of polyacrylamide, 0.05kg of polyglutamic acid microbial agent, 0.5kg of rice husk, 0.3kg of organic fertilizer, 0.1kg of compound fertilizer, and 0.1kg of water-soluble fertilizer in turn and dissolve them in water to obtain a soilless spraying base material.

[0050] Example 2

[0051] A soilless spraying substrate, comprising:

[0052] 4 kg of arsenic sandstone and sandy soil, 3 kg of wood fiber, 0.1 kg of potassium polyacrylate, 0.1 kg of polyacrylamide, 0.1 kg of polyglutamic acid microbial agent, 1 kg of rice husk, 1 kg of organic fertilizer, and 0.5 kg of inorganic fertilizer; the ratio of the arsenic sandstone to the sandy soil is 1:4; the particle size of the arsenic sandstone and sandy soil is 2 mm;

[0053] Wood fiber is produced by high-temperature and high-pressure detonation extraction process, with an organic matter content of ≥95%, a moisture content of 12%-18%, a water absorption rate of 1600%, and a biodegradability of 100%; the average fiber length is 10mm;

[0054] The organic fertilizer is a water-soluble fertilizer with an organic matter content of ≥50 g / L, an easily oxidizable organic matter content of ≥40 g / L, and a pH value (1:250 dilution) of 4.0;

[0055] Mix arsenic sandstone with 4kg of sandy soil, 3kg of wood fiber, 0.1kg of potassium polyacrylate, 0.1kg of polyacrylamide, 0.1kg of polyglutamic acid microbial agent, 1kg of rice husk, 1kg of organic fertilizer and 0.5kg of inorganic fertilizer in turn and dissolve them in water to obtain a soilless spraying base material.

[0056] Example 3

[0057] A soilless spraying substrate, comprising:

[0058] 3.5 kg of arsenic sandstone and sandy soil, 3 kg of wood fiber, 0.1 kg of potassium polyacrylate, 0.05 kg of polyacrylamide, 0.1 kg of polyglutamic acid microbial agent, 1 kg of rice husk, 0.5 kg of organic fertilizer, and 0.5 kg of inorganic fertilizer; the ratio of the arsenic sandstone to the sandy soil is 1:5; the particle size of the arsenic sandstone and sandy soil is 2 mm;

[0059] Wood fiber is produced by high-temperature and high-pressure detonation extraction process, with an organic matter content of ≥95%, a moisture content of 12%-18%, a water absorption rate of 1600%, and a biodegradability of 100%; the average fiber length is 10mm;

[0060] The organic fertilizer is a water-soluble fertilizer with an organic matter content of ≥50 g / L, an easily oxidizable organic matter content of ≥40 g / L, and a pH value (1:250 dilution) of 4.0;

[0061] Arsenic sandstone was mixed with 3.5 kg of sandy soil, 3 kg of wood fiber, 0.1 kg of potassium polyacrylate, 0.05 kg of polyacrylamide, 0.1 kg of polyglutamic acid microbial agent, 1 kg of rice husk, 0.5 kg of organic fertilizer and 0.5 kg of inorganic fertilizer in turn and dissolved in water to obtain a soilless spraying substrate.

[0062] Example 4

[0063] Ecological restoration of a sandy high and steep slope at a quartz sand production base in Shenmu City, Shaanxi Province

[0064] Test address: A quartz sand production base in Shenmu City, Shaanxi Province is located in a tributary of the Yellow River Basin in Shenmu City, upstream of the Changjiagou Reservoir. The base has high and steep exposed slopes formed by sand mining. The northern slope is 21-33 meters high and the overall slope is 24-33 degrees. The western slope is 26-60 meters high and the overall slope is 30-41 degrees. The local cut slope reaches 60 degrees. The top of the slope is covered with loess with a thickness of about 0.3-1m, which is mainly aeolian sand with low cohesion and serious soil and water loss.

[0065] The methods of ecological restoration are as follows:

[0066] 1) Renovate the sandy slopes and clean up the dangerous sand and soil; in areas where the slopes are too high, grade and slow the slopes, and build steps. Each step is 20 meters high and 1 meter wide.

[0067] 2) Manually drill vegetation holes with a diameter of 10 cm, a depth of 20 cm, and a density of 1 hole / m 2 , the spacing between planting holes is 100 cm, and they are arranged in a plum blossom shape;

[0068] 3) Artificially adding the substrate prepared in Example 1 to fill the planting holes, and simultaneously inserting seedlings of Amorpha fruticosa, Lespedeza bicolor, Vitex truncatum, and Vetiver;

[0069] 4) Spraying bottom layer: Spraying a mixed mud onto the surface of the sandy slope as a solidified layer with a thickness of 3 cm; the composition of the mixed mud is: 46.5% clean water, 1.5% potassium polyacrylate, 2% polyacrylamide, 20% organic and inorganic fertilizers, 20% arsenic sandstone, and 10% sandy soil;

[0070] 5) The soilless spraying substrate prepared in Example 1 and the mixed grass seeds were mixed evenly in a hydraulic sprayer to obtain a slurry mixture for spraying with a thickness of 8 cm; wherein the mixed grass seeds included the following grass seeds in parts by weight: 1 part of Salix serrata, 2 parts of Hippophae rhamnoides, 1 part of Achnatherum splendens, 1 part of Ailanthus altissima, 1 part of Amorpha fruticosa, 1 part of Medicago sativa, 1 part of Lespedeza bicolor, 2 parts of Ryegrass, and 1 part of Bermuda grass;

[0071] 6) Maintenance: After the spraying operation is completed, use a sprinkler truck to spray water and maintain maintenance to keep the construction surface moist. Cover the slope with a grass mat to retain water and moisture, prevent water evaporation, and ensure the germination rate of the grass seeds. Remove the grass mat after the seedlings emerge. Depending on the local weather conditions, water the grass every 20-30 days. Water thoroughly each time, and the amount of water each time is about 5m 3 / mu. This process lasts for 2 years.

[0072] Implementation Results: Spray seeding began in April 2022, and seeds germinated 6-7 days later, with a germination rate of approximately 90% for pioneer herbaceous plants. A month later, the slope was essentially greened. During the slope maintenance period, the survival rate of herbs and shrubs was 89%. Six months later, the slope's vegetation was growing steadily, with a plant coverage rate of approximately 92%. Grasses and shrubs flourished, and the sandy slope was stable, with no landslides. After a year of growth, herbaceous and shrubby plants grew vigorously, and a three-dimensional ecosystem of grasses, shrubs, and trees was initially established. The sandy slope was essentially greened, with a coverage rate of approximately 90%. The slope intercepted runoff by 42.8%-61.4%, and the slope's erosion protection was 69.5%-90.1%. The slope was essentially stable, with no landslides, and initial green plant coverage and stable plant growth were achieved.

[0073] Example 5

[0074] Ecological restoration of the steep sandy slopes at the historical sand mining site on the west bank of the Yellow River in Heyang County, Weinan City, Shaanxi Province

[0075] The test site is located in the abandoned sand mining site on the terraces and floodplains on the west bank of the Yellow River in Heyang County, Weinan City, Shaanxi Province. Extensive open-pit mining is very active in the loess gully area on the west bank of the Yellow River in Heyang County, and most of the mines are ownerless. The vegetation is severely damaged and the regional ecological environment is fragile. The high and steep exposed slopes formed by sand mining are about 300m long, about 38-54m high, and have a slope gradient of 28-62 degrees. The top of the slope is covered with a loess layer with a thickness of about 5-15m. The middle and lower parts of the slope are sand layers with a thickness of about 13-30m. It is mainly composed of medium and fine sand deposited by impact, with low cohesion.

[0076] The methods of ecological restoration are as follows:

[0077] 1) Renovate the sandy slope and clean up the dangerous sand and soil; in areas where the slope is too high, grade and slow down the slope and build steps, with each step 18 meters high and 2 meters wide;

[0078] 2) Manually drill vegetation holes with a diameter of 20 cm, a depth of 40 cm, and a density of 4 holes / m 2 , the spacing between planting holes is 40 cm, arranged in a plum blossom shape;

[0079] 3) artificially adding the loam-like substrate prepared in Example 2 to fill the planting holes, and simultaneously inserting the Amorpha fruticosa seedlings;

[0080] 4) Spraying bottom layer: First, wet the slope surface with water, then spray the mixed mud onto the sandy slope surface as a solidification layer, with a spraying thickness of 1 cm; the mixed mud composition is: 45% clean water, 0.5% potassium polyacrylate, 0.5% polyacrylamide, 20% fertilizer, 20% arsenic sandstone, and 14% sandy soil;

[0081] 5) The soilless seeding substrate prepared in Example 2 and the mixed grass seeds were mixed together in a hydraulic seeding machine to obtain a slurry mixture for seeding at a thickness of 2 cm; the mixed grass seeds included: 2 parts alfalfa, 2 parts sandwort, 2 parts sea buckthorn, 1 part tall fescue, 1 part geranium, and 2 parts amorpha;

[0082] 6) Maintenance: After the spraying operation is completed, use a sprinkler truck to spray water for maintenance to keep the construction surface moist. Cover the slope with a grass mat to retain water and moisture, prevent water evaporation, and ensure the germination rate of the grass seeds. Remove the grass mat after the seedlings emerge. Depending on the local weather conditions, water the grass every 20-30 days. Water thoroughly each time, and the amount of water each time should be about 5m 3 / mu. This process lasts for 2 years.

[0083] Implementation Results: Spray seeding began in March 2021, and seeds germinated after 5-6 days. The germination rate of pioneer herbaceous plants was approximately 92%, achieving significant greening results within one month. During the slope maintenance period, the survival rate of herbaceous and shrubby plants was 91%. Six months later, the slope vegetation had stabilized, reaching approximately 93% plant coverage. Grasses and shrubs flourished, and the sandy slopes remained stable, with no landslides. From September to October of that year, Heyang County experienced prolonged, heavy rainfall, with the highest single-day rainfall reaching approximately 130.1 mm on September 22nd, the highest in Heyang County in nearly 10 years (the highest single-day rainfall in Heyang County in the past 10 years is 114.7 mm). No large-scale collapse or spalling occurred in the demonstration area, and the slope vegetation showed strong resistance to erosion. Approximately 8% of the slope was damaged. However, in the untreated areas, extensive collapse, landslides, and soil erosion occurred, with approximately 50% of the slope damaged. The treated slopes were generally able to withstand prolonged, heavy rain. In the second year, herbaceous and shrubby plants flourished, and the sandy slopes were essentially covered with greenery, with a coverage rate of approximately 91%. The slopes were stable and free of landslides. In the third year, a three-dimensional ecosystem of grasses, shrubs, and trees was essentially established. Amorpha fruticosa and sea buckthorn had grown to over 2 meters in height, and the slopes had a plant coverage rate of approximately 90%, forming a stable plant community that harmonized with the surrounding environment. The slopes intercepted runoff by 53.4%-75.9%, and provided erosion protection by 71.3%-93.8%. The slopes were essentially stable with no landslides, achieving excellent greening results and meeting the requirements for the Heyang County West Bank Ecological Green Corridor.

[0084] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for ecological restoration of arid, steep, sandy slopes, characterized in that: The method comprises the following steps: After the sandy slope is renovated, planting holes are drilled, soilless spraying substrate is added to the planting holes, and shrub seedlings are inserted. A mixed mud is sprayed onto the surface of the sandy slope as a solidifying layer. Then, the soilless spraying substrate and grass seeds are mixed and sprayed onto the surface of the solidifying layer. The thickness of the solidifying layer is 1-3 cm, and the thickness of the substrate and grass seeds after spraying is 2-8 cm. The soilless spraying substrate comprises the following raw materials in parts by weight: 30-40 parts of arsenic sandstone and sandy soil, 25-30 parts of plant fiber, 0.5-1.0 part of soil water-retaining agent, 0.5-1.0 part of binder, 0.5-1.0 part of polyglutamic acid microbial agent, 5-10 parts of rice husks, and 5-15 parts of fertilizer; the ratio of the arsenic sandstone to the sandy soil is 1:2-1:5; the particle size of the arsenic sandstone and sandy soil is ≤2mm.

2. The method for ecological restoration of arid, steep sandy slopes according to claim 1, characterized in that: The plant fibers include wood fibers and / or grass fibers.

3. The method for ecological restoration of arid, steep sandy slopes according to claim 1, characterized in that: The soil water-retaining agent comprises any one of acrylamide-acrylate copolymer cross-linking product, starch-acrylate graft copolymer cross-linking product, potassium polyacrylate, and polyacrylamide.

4. The method for ecological restoration of arid, steep, sandy slopes according to claim 1, characterized in that: The binder is anionic polyacrylamide or starch-modified acrylic acid-acrylamide copolymer resin.

5. The method for ecological restoration of arid, steep sandy slopes according to claim 1, characterized in that: The polyglutamic acid microbial agent is compounded by functional microorganisms and polyglutamic acid, wherein the functional microorganisms include Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus gelatinous, and Trichoderma harzianum; and the effective viable count of the polyglutamic acid microbial agent is ≥2 billion / ml.

6. The method for ecological restoration of arid, steep, sandy slopes according to claim 1, characterized in that: The fertilizer includes organic fertilizer and / or inorganic fertilizer.

7. The method for ecological restoration of arid, steep sandy slopes according to claim 1, characterized in that: The preparation method of the soilless spraying substrate comprises the following steps: The soilless spraying substrate is obtained by sequentially mixing water, fertilizer, soil water retaining agent, adhesive, polyglutamic acid microbial agent, plant fiber, rice husk, arsenic sandstone and aeolian sand soil, and fully dissolving them.

8. The method for ecological restoration of arid, steep, sandy slopes according to claim 1, characterized in that: The mixed mud comprises the following components in percentage by weight: 35%-60% of clean water, 0.5%-1.5% of water retaining agent, 0.5%-2% of adhesive, 10%-20% of fertilizer, 10%-30% of arsenic sandstone, and 5%-15% of wind-blown sand soil.