A method for cultivating a three-dimensional production of sand biological soil crust blanket

Abstract

The application discloses a cultivation method for producing a three-dimensional biological soil crust carpet. The biological soil crust is made into a crust seed source, a water-permeable isolation layer, a granular drainage layer and a degradable natural fiber carrier are sequentially laid in a seedling tray, and multiple seedling trays are layered and placed on a cultivation frame. Each layer is provided with a micro-spraying water supply component which can be independently or zonally controlled; after inoculation, a film is covered for moisture retention, and nutrient solution is supplemented regularly, and after the film is removed, layered micro-spraying water supply is implemented, and the trays are circulated between different layers and inner and outer positions according to a predetermined period, so that each cultivation unit obtains relatively balanced cumulative light, ventilation and water supply conditions. Moss plants, sandy substrates and fiber carriers are combined to form a biological soil crust carpet which can be integrally taken out and curled for transportation. The method can improve the yield per unit area and the uniformity of products in batches.

Description

Technical Field

[0001] This invention belongs to the field of desertification control and artificial cultivation technology of biological soil crusts. Specifically, it relates to a cultivation method for large-scale production of sandy soil biological crust blankets through multi-layer cultivation, layered water supply and cyclical replacement of cultivation units, and the sandy soil biological crust blankets obtained by this method. Background Technology

[0002] Land desertification poses a persistent threat to ecological security, agricultural production, and the human living environment. Physical measures such as straw checkerboard sand barriers and high-pole fences can reduce near-surface wind speeds for a certain period, but they usually require a large amount of materials and labor, and the materials need to be replaced after they age. Directly sowing higher plants is susceptible to insufficient water, wind erosion, and sand burial, which limits the survival rate and recovery speed.

[0003] Biocrust mats are living, peelable materials formed by the artificial cultivation of moss plants, substrate particles, and the carrier, using biodegradable natural fiber materials as a carrier. They consist of a composite surface layer formed by algae, mosses, lichens, fungi, bacteria, and their secretions, combined with soil particles. Through mycelia, rhizoids, and extracellular polymers, they bind sand particles, enhancing the surface's resistance to wind erosion. They also trap dust, increase organic matter and nutrients, and create conditions for vascular plants to establish themselves.

[0004] To shorten the natural crust formation cycle, existing technologies have attempted to artificially propagate crusts in planar spaces such as seedling trays and ground cultivation ponds before transplanting them to the treatment area. For example, Chinese invention patent CN104350932A (Northwest A&F University, 2014) uses a cultivation container with a diameter of 18 cm and a height of 2 cm for planar cultivation; Chinese invention patent CN118476443 (2024) uses an indoor potted method for planar layered cultivation; Chinese invention patent CN107058117A (Yan'an University, 2016) focuses on the promotion of biological crust cultivation by fungal extracellular polysaccharides; and Chinese invention patent CN102268376A (Xinjiang Institute of Ecology and Geography) involves indoor single-species cultivation of Microsheathellae. Furthermore, while CN116948923A (Inner Mongolia Agricultural University, 2023) and CN106538100A (Inner Mongolia Agricultural University, 2016) involve a "three-dimensional protection model," their essence is to utilize biological crusts to form a "surface-above-ground" ecological protection system with plants, rather than implementing three-dimensional multi-layer cultivation of the crust cultivation process itself. None of the aforementioned existing technologies involve the large-scale production of moss crust mats under a three-dimensional multi-layer structure. However, planar cultivation requires a large area, has limited output per unit land area, and is easily affected by local environmental factors such as temperature, humidity, light, and water supply. Simply stacking multiple trays on ordinary shelves may result in insufficient shading and ventilation in the lower layers, rapid evaporation in the upper layers, and uneven water and fertilizer distribution due to uniform spraying, leading to significant differences in coverage, plant height, and mat formation time among the layers.

[0005] Therefore, there is a need for a biological mat cultivation method that can make full use of three-dimensional space while taking into account stratified water supply, balanced lighting, ventilation, and product transportability, in order to increase yield per unit area and reduce batch-to-batch quality variation. Summary of the Invention

[0006] The technical problem this invention aims to solve is that existing artificial cultivation methods for sandy soil biological crusts mostly employ a single-layer planar cultivation model, resulting in large land occupation and low yield per unit area. If multi-layer stacking cultivation is used, the upper layers receive ample sunlight and have high evaporation rates, while the lower layers suffer from severe shading and insufficient ventilation. Unified spraying water supply leads to uneven water and fertilizer distribution across layers. Long-term cultivation in fixed layers results in significant differences in moss coverage and matting cycle between different trays, leading to poor batch uniformity. Furthermore, traditional cultivation substrates lack stratified drainage and shaping carriers, making it impossible to peel off the cultivated crust as a whole, roll it up, and transport it, posing significant challenges to engineering installation. The purpose of this invention is to overcome the shortcomings of existing planar cultivation methods, such as low space utilization, uneven microenvironment in multi-layer cultivation, and inability to transport finished products in an integrated manner. This invention provides a three-dimensional cultivation method for producing sandy soil biological crust mats, along with sandy soil biological crust mats prepared by this method that can be peeled off and rolled up for overall installation. This simultaneously improves cultivation capacity per unit area and batch product quality uniformity. The cultivated finished products can be transported as a whole, making it suitable for large-scale ecological restoration projects in arid and semi-arid sandy areas.

[0007] To solve the above-mentioned technical problems, the first aspect of the present invention provides a method for cultivating three-dimensional sandy soil biological crust, comprising the following steps: S1. Preparation of soil crust seed source: Collect soil crusts from sandy soil organisms, and obtain soil crust seed source by air drying, impurity removal, crushing and mixing. S2. Assemble the cultivation unit: In the seedling tray, from bottom to top, lay a permeable isolation layer, a granular drainage layer, and a biodegradable natural fiber blanket carrier to form an independent cultivation unit. S3. Construct a three-dimensional cultivation system: Arrange multiple cultivation units in layers on the cultivation rack, each layer is equipped with micro-spray water supply components that can be independently or zonedly controlled, and shading components are installed above the cultivation rack; S4. Inoculate and spray growth-promoting microbial solution: Evenly spread the crust-forming seed source on the surface of the mat-like carrier, moisten it, spray the growth-promoting microbial solution, and cover it with a light-transmitting and moisture-retaining film. S5. Maintenance during the mulching stage: During the mulching period, regularly remove the film for ventilation and spray with modified Hogland nutrient solution. Remove the light-transmitting and moisture-retaining film after the moss seedlings have a coverage of more than 30%. S6. Layered water supply and cyclic rotation after film removal: After film removal, water is supplied in layers through micro-spray water supply components. Different layers and the inner and outer sides of the same layer are rotated according to a predetermined cycle to balance the cumulative differences in light, ventilation and water supply of each cultivation unit. S7. Finished product shaping and cultivation: Continue to maintain the moss plants, sandy substrate particles and blanket-like carrier to obtain a sandy biological crust blanket that can be peeled off as a whole and rolled up for transportation.

[0008] Further, in step S1, the thickness of the soil crust collected from sandy soil organisms is 0.5–1.0 cm, and the mesh size of the crushing sieve is 1–3 mm; the crust seed source is selected from one or more combinations of *Bryophytum sclerotium*, *Bryophytum breviflorum*, and *Bryophytum verticillatum*. Further, the mat-like carrier is 40–80 mesh jute cloth, ramie cloth, or a blend of both, cut to a size of 35–45 cm × 35–45 cm; the permeable isolation layer is made of geotextile, and the granular drainage layer is volcanic rock, with 1.0–2.0 kg of granular drainage layer laid on a 40 cm × 40 cm seedling tray. Further, the cultivation rack is set with 3–8 layers, with a layer spacing of 30–60 cm; each layer is equipped with 2–5 atomizing micro-sprayers, with a single sprayer flow rate of 25–45 L / h and a spray radius of 0.6–0.8 m; the cultivation unit rotation cycle is 5–10 days. Furthermore, the growth-promoting microbial solution is *Rhodopseudomonas palustris* solution, *Chlorella vulgaris* suspension, or a mixture of both; the *Rhodopseudomonas palustris* stock solution is added at a rate of 8–16 mL / L to the working solution, and the growth-promoting microbial solution is sprayed at a rate of 1–4 L / m². Furthermore, the seed source for crust formation is sown at a rate of 300–600 g / m²; during the film-covered culture stage, the film is removed every 5–10 days for ventilation and spraying with modified Hogrange nutrient solution; the film is removed 20–40 days after inoculation, and water is supplied via micro-spraying 3–8 times daily after film removal, with a single water supply of 0.5–1.5 L / m², for a total cultivation period of 60–120 days. Furthermore, the improved Hogland nutrient solution is a compound of three mother solutions: A, B, and C. Mother solution A contains 40–55 g / L of calcium nitrate tetrahydrate; mother solution B contains 10–18 g / L of potassium dihydrogen phosphate and 40–60 g / L of magnesium sulfate heptahydrate; mother solution C contains 3–7 g / L of ferric disodium ethylenediaminetetraacetate, 1.0–2.0 g / L of boric acid, 0.5–1.3 g / L of manganese chloride tetrahydrate, 0.05–0.20 g / L of zinc sulfate heptahydrate, 0.02–0.08 g / L of copper sulfate pentahydrate, and 0.005–0.03 g / L of ammonium molybdate tetrahydrate. 1–3 mL of each of mother solutions A, B, and C are added per liter of working solution to adjust the pH to 7.5–8.0.

[0009] A second aspect of this invention provides a sandy biocrust mat, prepared by any of the above-described cultivation methods; the sandy biocrust mat comprises, from bottom to top, a biodegradable natural fiber carrier layer, a sandy matrix layer embedded in the carrier, and a bioactive layer composed of drought-resistant moss; the overall thickness of the mat is 3-6 mm, with moss rhizoids, sand particles, and the carrier interlocked, allowing for complete removal and transport by curling. Further, the bioactive layer contains two or three of *Bryophytum sclerotium*, *Bryophytum brevifolium*, and *Bryophytum verticillatum*; the vertical projection coverage of the finished bioactive layer is not less than 75%, and the moss can remain in a dormant or revived state.

[0010] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention adopts a multi-layer cultivation rack to arrange cultivation units in a three-dimensional manner, making full use of vertical space, greatly increasing the number of cultivation units arranged within a unit area, increasing the output per unit area, and solving the defects of traditional planar cultivation that have large land area and low production capacity.

[0011] (2) Each layer is equipped with an independent adjustable micro-spray water supply system, which, together with the periodic operation of changing positions between upper and lower layers and between the inner and outer sides of the same layer, ensures that all cultivation units are evenly subjected to different light, ventilation and moisture environments, significantly reducing the differences in moss coverage and carpeting cycle between different cultivation units within the same batch, and improving the uniformity of the finished product.

[0012] (3) The seedling tray is equipped with a three-layer composite structure consisting of a permeable isolation layer, a volcanic rock drainage layer, and a biodegradable natural fiber carrier. It has the functions of rapid drainage and prevention of water accumulation, as well as moss rhizoid wrapping and shaping. After the formation, the crust blanket relies on the fiber carrier to form a complete whole, which can be peeled off in one piece, rolled up and transported, greatly reducing the difficulty of on-site construction for sandy land ecological restoration.

[0013] (4) The present invention is equipped with a modified Hogland nutrient solution adapted to the alkaline environment of sandy land, and combined with Rhodopseudomonas swampus and Chlorella growth-promoting microbial solution to construct a fungus-algae-moss synergistic growth system, which accelerates moss germination and colonization and significantly shortens the artificial crusting cultivation cycle.

[0014] (5) The finished mat has a stable structure, the moss can maintain a dormant state for easy long-distance storage and transportation, the fiber carrier can be naturally degraded without secondary pollution, and after laying, it can quickly bind sand particles to resist wind erosion. It is suitable for ecological restoration of various desertification areas such as mobile sandy land, semi-fixed sandy land, and bare land disturbed by engineering. It has strong practicality for industrialization. Attached Figure Description

[0015] Figure 1 The images show the growth status of the crust at 15, 30, 60 and 120 days after inoculation in Example 1 (coverage is -, about 30%, about 50% and ≥90%, respectively; plant height is -, 0.5-2 mm, 1-4 mm and 2-6 mm, respectively).

[0016] Figure 2 The images show the growth status of the crust 30 days and 60 days after inoculation in Example 2 (coverage of approximately 50% and ≥90%, respectively; plant height of 0.5–2.5 mm and 2–6 mm, respectively).

[0017] Figure 3 The image shows the growth status of the crust 60 days after inoculation in Example 3 (coverage of approximately 75%, plant height of 0.5–3 mm).

[0018] Figure 4 This is a diagram of a planar cultivation site for Comparative Example 1 (the yield per unit area is 1 / 3 to 1 / 5 of that of three-dimensional cultivation).

[0019] Figure 5 A site diagram showing the layout of multi-layer cultivation racks and cultivation units (when the layers are fixed, the difference in coverage between the upper and lower layers can reach 15% to 25%, and cyclic repositioning can effectively reduce the cumulative difference). Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments. It should be noted that the following embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention; where there is no conflict, the technical features of the various embodiments can be combined with each other. Experimental methods not specifying specific conditions were performed according to conventional conditions in the art.

[0021] In this embodiment, the cultivation system and process parameters used are shown in the table below: Table 1. Cultivation system and process parameters used in biological crust formation. Seed preparation Thickness 0.5~1.0 cm Approximately 0.5 cm Seed preparation Crushing screen mesh size 1–3 mm 2 mm carrier Material and Specifications Jute / ramie, 40~80 mesh 60 mesh jute cloth carrier Cutting dimensions 35-45 cm square 39 cm × 39 cm Culture tray Pallet size 38–45 cm square 40 cm × 40 cm Culture tray Granular drainage layer 1.0~2.0 kg / tray 1.5 kg volcanic rock Cultivation rack Number of layers and spacing between layers 3-8 layers, 30-60 cm 5 layers, 40 cm Micro-spraying Flow / radius 25–45 L / h; 0.6–0.8 m Adjust the layer coverage evenly. Vaccination Seed distribution amount 300~600 g / m² 427 g / m² environment illumination 1000～12000 lx Adjust according to growth stage environment temperature 2～35 ℃ 15～30 ℃ Nutrition Nutrient solution cycle Once every 5 to 10 days Once every 7 days Water supply after membrane removal Frequency / Single Water Volume 3–8 times / day; 0.5–1.5 L / m² Adjust according to the degree of dryness and humidity Change of layer cycle Every 5–10 days Every 7 days Cultivation cycle 60～120 d Approximately 90 days Prepare three concentrated mother liquors, A, B, and C, and store them in the dark. Mother liquor A is a calcium source, containing 47.24 g / L calcium nitrate tetrahydrate; mother liquor B is a phosphorus, potassium, and magnesium source, containing 13.62 g / L potassium dihydrogen phosphate and 49.30 g / L magnesium sulfate heptahydrate; mother liquor C is a trace element and iron source, containing 5.0 g / L ferric disodium ethylenediaminetetraacetate, 1.43 g / L boric acid, 0.91 g / L manganese chloride tetrahydrate, 0.11 g / L zinc sulfate heptahydrate, 0.04 g / L copper sulfate pentahydrate, and 0.01 g / L ammonium molybdate tetrahydrate. To prepare 1 L of working solution, first add approximately 900 mL of distilled water, then add 2 mL each of mother liquors A, B, and C in sequence, mix well, and bring the volume to 1 L. Adjust the pH to 7.5–8.0 with sodium hydroxide solution (if the pH is too high, it can be adjusted with dilute hydrochloric acid or dilute sulfuric acid).

[0022] Regarding the dosage of the growth-promoting microbial solution: The amount of stock solution of *Rhodopseudomonas palustris* added to the working solution can be 8–16 mL / L, preferably 12 mL / L. Too low a dosage (<8 mL / L) will result in insignificant growth-promoting effects and make it difficult to establish a stable synergistic microbial environment in the short term; too high a dosage (>16 mL / L) can easily lead to excessive microbial proliferation on the moss carpet surface, affecting moss colonization. The spraying amount of the growth-promoting microbial solution should be such that the carpet surface is evenly moistened without forming obvious water accumulation, typically 1–4 L / m², preferably 2–3 L / m²; too little spraying cannot ensure sufficient contact between the microorganisms and the seed source, while too much spraying can easily lead to substrate water accumulation and poor aeration.

[0023] The following cultivation steps are adopted: (1) Collect mature moss crusts that are similar to the environment of the target treatment area, place them in a cool and ventilated place to dry, remove dead branches, broken leaves and stones, crush and mix them.

[0024] (2) Cut 60-mesh jute cloth into 39 cm × 39 cm pieces, soak in water and wash. If necessary, treat with hot water or low-concentration disinfectant for a short time and then rinse thoroughly.

[0025] (3) Lay 39 cm × 39 cm geotextile at the bottom of a 40 cm × 40 cm seedling tray, and evenly spread about 1.5 kg of cleaned volcanic rock; place jute cloth on top of the volcanic rock and soak it thoroughly.

[0026] (4) Place the cultivation trays on a double-row, multi-layer cultivation rack, install atomizing micro-sprayers on each layer, and set up a shade net on the top layer. Check the spray coverage of each layer and adjust the water pressure to ensure that the tray surface is basically evenly watered.

[0027] (5) Spread the seed source evenly at 427 g / m² and moisten it with spray; then spray with working solution of Rhodopseudomonas swampus or Chlorella suspension and cover with white transparent film.

[0028] (6) Keep the substrate moist during the covering period, remove the film every 7 days to ventilate and spray with about 2.1 L / m² of modified Hogland nutrient solution. After new shoots appear and stable cover is formed (coverage reaches more than 30%), the film is usually removed after about 30 days.

[0029] (7) After the film is removed, water is supplied by a layered micro-spraying system 3 to 8 times a day, with a single water application of about 1 L / m²; the specific frequency is adjusted according to the temperature, air humidity and the dryness of the carpet surface.

[0030] (8) Adjust the position of each layer of the cultivation tray every 7 days, and continue to cultivate until the coverage reaches more than 75% and the moss, substrate and burlap are firmly bonded; when the coverage reaches more than 90%, remove the tray.

[0031] Example 1: Five-layer three-dimensional cultivation in autumn and winter From October 2023 to January 2024, cultivation was carried out in a greenhouse in Yangling District, Xianyang City, Shaanxi Province, using a five-layer three-dimensional cultivation rack. The greenhouse was not equipped with active heating or cooling systems, and the measured temperature was approximately -4 to 35 ℃, with light intensity ranging from 0 to 18,000 lx. Shading nets were used to control the light intensity at the cultivation trays within a suitable range during periods of strong light.

[0032] Moss crusts, approximately 0.5 cm thick, were collected from the Mu Us Desert. After air-drying and impurity removal, the crusts were pulverized using a 2 mm sieve. Culture trays were prepared and inoculated according to standard procedures, with a sowing rate of 427 g / m². A growth-promoting microbial solution was sprayed, followed by covering with a film. The film was removed every 7 days for ventilation and sprayed with 2.1 L / m² of modified Hogrange nutrient solution. After approximately 30 days, when the coverage reached over 30%, the film was removed. After removal, micro-sprinkler irrigation was used, and the soil layer was changed every 7 days.

[0033] New branches can be seen after 15 days of cultivation; after 30 days of cultivation, the coverage is about 30% and the plant height is about 0.5-2 mm; after 60 days of cultivation, the coverage is about 50% and the plant height is about 1-4 mm; after 120 days of cultivation, the coverage reaches more than 90% and the plant height is about 2-6 mm, and the blanket can be completely removed.

[0034] Example 2: Three-layer vertical cultivation in spring and summer From April to June 2025, the seed culture was carried out in the same greenhouse using a three-layer cultivation rack. The greenhouse temperature was approximately 15–35 °C, and the light intensity at the cultivation trays was controlled between 0 and 12000 lx. Seeds were collected at the end of March and processed according to the method in Example 1.

[0035] Place the cleaned jute cloth on the soaked culture tray, evenly sprinkle the seed source, spray with water and apply growth-promoting microbial solution, then cover with a film for cultivation. Spray with 2.1 L / m² of modified Hogland nutrient solution every 7 days and aerate; when the coverage reaches more than 30% after 30 days of cultivation, remove the film, turn on the micro-spraying system and change the layer every 7 days.

[0036] After 30 days, the coverage is about 50% and the plant height is about 0.5 to 2.5 mm; after 60 days, the coverage reaches more than 90% and the plant height is about 2 to 6 mm, forming a dense and curable biological mat.

[0037] Example 3: Low-level cultivation during high-temperature season Cultivation will take place during the high-temperature season in the greenhouse from July to August 2025. The greenhouse air temperature will be approximately 26–45 °C. Cultivation trays will be preferentially placed at the bottom of the cultivation racks, and shading and evaporative cooling pads will be used to ensure that the maximum temperature on the carpet surface does not exceed 38 °C. Seeds will be collected at the end of April and processed using the methods described above.

[0038] The inoculation and covering conditions were the same as in Example 2. During the covering period, nutrient solution was sprayed and aeration was provided every 7 days; after the film was removed, the frequency of micro-spraying was increased according to the dryness and wetness of the blanket surface, and prolonged water accumulation was avoided during the midday high temperature period.

[0039] After 60 days of cultivation, the canopy coverage was approximately 75%, and the plant height was approximately 0.5–3 mm. The results indicate that during the high-temperature season, by lowering the cultivation layer, strengthening shading, and increasing evaporative watering, skin formation and propagation can still be achieved, but the rate of canopy formation is lower than under suitable temperature conditions in spring and summer.

[0040] Example 4: Compound growth-promoting microbial solution Based on Example 2, the biofilm-promoting microbial solution was prepared as a mixture of *Rhodopseudomonas palustris* working solution and *Chlorella* suspension. The *Rhodopseudomonas palustris* stock solution was diluted with water at a concentration of 12 mL / L. After wetting the inoculum, the working solution was sprayed evenly first, followed by the *Chlorella* suspension, ensuring the biofilm surface was evenly moistened without significant water accumulation. Other conditions remained the same as in Example 2. This method is suitable for scenarios where it is desirable to simultaneously introduce bacterial and algal components to accelerate the initial formation of the surface biofilm.

[0041] Comparative Example 1: Planar Culture The same number of culture trays as in Example 2 were laid flat in a single layer on the greenhouse floor, and the same seed source, carrier, and nutrient solution were used for cultivation. This method does not involve three-dimensional stacking. Although each tray receives sufficient light, only one layer of culture trays can be arranged per unit area. To achieve the same yield, the area required is approximately three times that of the three-layer cultivation method and approximately five times that of the five-layer cultivation method. This comparative example is used to illustrate the improved space utilization efficiency of three-dimensional cultivation and should not be interpreted as an absolute limitation on biomass production.

[0042] Comparative Example 2: Multilayer cultivation without changing layers A five-layer cultivation rack was used, but the positions of the cultivation trays were not adjusted during cultivation, and other conditions were the same as in Example 1. Due to differences in light, temperature, ventilation, and evaporation conditions between different layers, differences in the coverage and matting time between upper and lower cultivation trays were more likely to occur. Comparative observations showed that when the layers were fixed, the difference in coverage between upper and lower layers could reach 15%–25%, and the matting time could differ by 10–20 days. Circulating layer changes allowed each tray to experience different layer environments, thereby reducing the cumulative differences caused by long-term fixed layer placement and improving the uniformity of products within the batch.

[0043] The resulting sandy biocrust consists of a natural fiber carrier layer, a sandy matrix layer, and a bioactive layer from bottom to top. The carrier layer provides tensile and shaping support; the matrix layer provides moisture and an attachment medium for moss growth; and the bioactive layer contains drought-resistant moss and associated microorganisms. The overall thickness of the blanket is typically 3–6 mm. This thickness is directly related to the height of the moss plants: in Example 1, the plant height was 2–6 mm after 120 days of cultivation; in Example 2, the plant height was 2–6 mm after 60 days of cultivation; and the overall blanket thickness after covering with the moss layer and the associated sandy matrix can reach 3–6 mm (the actual measured thickness of the finished blanket in Example 1 was approximately 4 mm, in Example 2 it was approximately 3.5–4.5 mm, and in Example 3 it was approximately 3–4 mm). Before cultivation is complete, water can be moderately controlled to keep the blanket in a dormant or low-metabolic state, after which it is rolled up, packed, and transported.

[0044] During construction, remove sharp debris from the surface of the sandy area to be treated, level and moisten it appropriately, then unfold and lay the moss mat, overlapping or tightly splicing the edges of adjacent mats, and securing them with biodegradable ground nails. Water should be added as needed based on the weather during the initial laying stage. Once the moss has recovered and integrated with the original sand surface, gradually reduce manual maintenance.

[0045] Without departing from the inventive concept, the natural fiber carrier can be replaced by ramie cloth, coconut fiber mesh, or other fiber fabrics with water-permeable, air-permeable, and biodegradable properties; the granular drainage layer can be made of volcanic rock, ceramsite, gravel, or a combination thereof; the cultivation rack can be a single-row or double-row fixed, mobile, or modular structure; the water supply method can be micro-sprinkler, drip irrigation, or a combination of both; the shading component can be a shading net, adjustable louvers, or greenhouse shading curtain; environmental control can be achieved through natural ventilation, wet curtains, fans, heating, or supplemental lighting. All the above substitutions are equivalent embodiments of the inventive concept. The seedling trays, cultivation racks, micro-sprinkler components, natural fiber cloth, and nutrient solution raw materials used in this invention can all be obtained through conventional industrial methods. The process is repeatable and can be mass-produced in greenhouses or indoor facilities to produce transportable sand biocrust mats, suitable for ecological restoration of mobile sand dunes, semi-fixed sand dunes, disturbed bare land, and other arid and semi-arid regions, possessing industrial practicality.

Claims

1. A method for cultivating three-dimensional sandy soil biological crusts, characterized in that, Includes the following steps: S1. The soil crust of the sandy land is dried in the shade, impurities are removed, crushed and mixed evenly to obtain the crust seed source; S2. A permeable isolation layer, a granular drainage layer, and a biodegradable natural fiber blanket-like carrier are laid in the seedling tray from bottom to top to form a cultivation unit; S3. Multiple cultivation units are arranged in layers on a cultivation rack, each layer is equipped with a micro-spray water supply component that can be independently or zone-controlled, and a shading component is set above the cultivation rack; S4. The seed source for crusting is evenly sown on the surface of the blanket-like carrier, moistened, sprayed with growth-promoting microbial liquid, and covered with a light-transmitting and moisture-retaining film. S5. During the covered cultivation period, the film should be removed regularly for ventilation and modified Hogland nutrient solution should be sprayed. When the coverage of the moss seedlings reaches more than 30%, the light-transmitting and moisture-retaining film should be removed. S6. After the membrane is removed, the micro-spray water supply component is used to supply water in layers, and the cultivation units in different layers and the inner and outer sides of the same layer are rotated in a predetermined cycle to reduce the difference in cumulative light, ventilation and water supply caused by the fixed layer position of each cultivation unit. S7. Continue cultivation until the moss plants, sandy substrate particles and the blanket-like carrier combine to form a sandy biological crust blanket that can be peeled off as a whole.

2. The cultivation method according to claim 1, characterized in that, In step S1, the thickness of the collected sandy soil crust is 0.5–1.0 cm, and the mesh size of the crushing sieve is 1–3 mm; the crust seed source includes *Pseudomonas sclerotiorum* (…). Barbula rigidula ), slender short moon moss ( Brachymenium exile ) and true moss ( Bryum argenteum One or more combinations of ) 3. The cultivation method according to claim 1, characterized in that, The blanket-like carrier is jute cloth, ramie cloth, or a blend of jute and ramie, with a mesh size of 40-80 and a cut size of 35-45 cm × 35-45 cm.

4. The cultivation method according to claim 1, characterized in that, The permeable isolation layer is geotextile; the granular drainage layer is volcanic rock; for a 40 cm × 40 cm seedling tray, the amount of the granular drainage layer is 1.0–2.0 kg.

5. The cultivation method according to claim 1, characterized in that, The cultivation rack has 3 to 8 layers with a layer spacing of 30 to 60 cm; each layer is equipped with 2 to 5 atomizing micro-nozzles, with a flow rate of 25 to 45 L / h and a spray radius of 0.6 to 0.8 m for each atomizing micro-nozzle; the cycle of the cyclic rotation is 5 to 10 days.

6. The cultivation method according to claim 1, characterized in that, The growth-promoting microbial solution is *Rhodopseudomonas palustris* (… Rhodopseudomonas palustris ) liquid, chlorella ( Chlorella The solution may be a suspension or a mixture thereof; the amount of Rhodopseudomonas palustris stock solution added to the working solution is 8–16 mL / L, and the amount of the growth-promoting microbial solution sprayed is 1–4 L / m².

7. The cultivation method according to claim 1, characterized in that, The seed source for the crust formation was sown at a rate of 300–600 g / m². During the covered culture period, the film was removed every 5–10 days for ventilation and spraying with modified Hogland nutrient solution. The film was removed 20–40 days after inoculation. After the film was removed, water was sprayed 3–8 times a day, with a single water supply of 0.5–1.5 L / m². The culture period was 60–120 days.

8. The cultivation method according to claim 7, characterized in that, The modified Hogrange nutrient solution is prepared from stock solution A, stock solution B, and stock solution C. Stock solution A contains 40–55 g / L calcium nitrate tetrahydrate; stock solution B contains 10–18 g / L potassium dihydrogen phosphate and 40–60 g / L magnesium sulfate heptahydrate; stock solution C contains 3–7 g / L ferric disodium ethylenediaminetetraacetate, 1.0–2.0 g / L boric acid, 0.5–1.3 g / L manganese chloride tetrahydrate, 0.05–0.20 g / L zinc sulfate heptahydrate, 0.02–0.08 g / L copper sulfate pentahydrate, and 0.005–0.03 g / L ammonium molybdate tetrahydrate. 1–3 mL of each of stock solution A, stock solution B, and stock solution C are added to each liter of working solution, and the pH is adjusted to 7.5–8.

0.

9. A kind of sandy biological crust blanket, characterized in that, Prepared by the cultivation method according to any one of claims 1 to 8, the sandy biological crust blanket comprises, from bottom to top, a biodegradable natural fiber carrier layer, a sandy matrix layer embedded and combined with the carrier layer, and a bioactive layer formed by drought-resistant moss; the overall thickness of the sandy biological crust blanket is 3 to 6 mm, and the rhizoids of the moss plants, the sandy matrix particles and the carrier layer are combined with each other, so that the sandy biological crust blanket can be peeled off as a whole and rolled up for transportation.

10. The sandy biological crust blanket according to claim 9, characterized in that, The bioactive layer contains *Pseudomonas sclerotiorum* (… Barbula rigidula ), slender short moon moss ( Brachymenium exile ) and true moss ( Bryum argenteum Two or three of the following: Measured using the vertical projection method, the coverage of the bioactive layer is not less than 75% when the cultivation is completed, and the moss is in a dormant or revived state.

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