Slow-release type ecological grass blanket for improving eroded inferior land and construction method of slow-release type ecological grass blanket

Abstract

The invention provides a slow-release ecological grass blanket for improving an eroded inferior land and a construction method of the slow-release ecological grass blanket. The ecological grass blanket comprises a bottom intercepting layer, a nutrient slow-release layer, a seed triggering layer and a surface fixing layer which are sequentially arranged on the soil surface of the eroded inferior land. The bottom interception layer at least comprises a water-soluble lower film arranged on the soil surface and a first composite substrate layer arranged on the water-soluble lower film; the nutrient slow-release layer at least comprises an organic fertilizer mixture particle layer arranged on the first composite substrate layer and a water-soluble upper film arranged on the organic fertilizer mixture particle layer; the seed triggering layer comprises a degradable fiber lower net arranged on the water-soluble upper film and a composite seed belt arranged on the degradable fiber lower net; the surface fixing layer comprises a second composite substrate layer arranged on the composite seed belt and a degradable fiber net arranged on the second composite substrate layer. The ecological grass blanket provided by the invention is high in seed survival rate, good in uniformity, low in cost and capable of realizing sustainable ecological restoration.

Description

Technical Field

[0001] The present invention relates to the technical field of soil and water protection, and particularly to a slow-release ecological grass blanket for improving eroded badlands and a construction method thereof. Background Art

[0002] Red soil is one of the important tropical soil resources in China. There are many four-coordinate and six-coordinate metal compounds in red soil, including iron compounds and aluminum compounds, which is the growth base for fruit trees such as citrus. However, in the initial stage of improving eroded badlands in the red soil area, the soil is barren and difficult to utilize, soil erosion is serious, vegetation cannot grow and develop normally, and the survival rate is low.

[0003] In the field of traditional ecological restoration of eroded badlands, engineering measures such as "forest-shrub-grass mode" and "upper intercept, middle cut, lower block, internal and external greening" have achieved stage results, but there are still new problems. For example, the cost of laying turf is relatively high, and conventional grass blankets use one-time nutrient release, which does not match the vegetation growth cycle. Direct seeding of plants is affected by rainfall scouring, the seeds are washed away seriously, and the initial soil infertility leads to low vegetation survival rate. In addition, in the field of protection of newly built infrastructure projects, the current mainstream technologies include three-dimensional vegetation nets, concrete diamond-shaped frame slope protection, etc., which have ecological compatibility defects. For example, due to the planar seeding layer structure of traditional vegetation blankets, the seeds are unevenly distributed under the scouring of slope runoff, and the slow-release fertilizer particles filled inside are easily washed away quickly by rainwater, increasing the maintenance cost of multiple replantings and fertilizations in the later stage. The concrete diamond-shaped frame slope protection can quickly fix the soil and is suitable for sections prone to debris flows and landslides, but it is not suitable for general sections or terraced slope protection scenarios, resulting in waste of resources, high cost, and damage to the soil environment, and it cannot provide nutrients for plant growth. Summary of the Invention

[0004] Based on this, the purpose of the present invention is to provide a slow-release ecological grass blanket for improving eroded badlands and a construction method thereof to solve the technical problems existing in the prior art.

[0005] On the one hand, the present invention provides a slow-release ecological grass blanket for improving eroded badlands, including a bottom interception layer, a nutrient slow-release layer, a seed trigger layer, and a surface fixing layer sequentially arranged on the eroded badland soil surface;

[0006] The bottom interception layer at least includes a water-soluble lower film arranged on the soil surface and a first composite matrix layer arranged on the water-soluble lower film;

[0007] The nutrient slow-release layer at least includes an organic fertilizer mixture particle layer arranged on the first composite matrix layer and a water-soluble upper film arranged on the organic fertilizer mixture particle layer;

[0008] The seed trigger layer includes a degradable fiber lower net arranged on the water-soluble upper film and a composite seed belt arranged on the degradable fiber lower net;

[0009] The surface fixing layer includes a second composite matrix layer provided on the composite seed belt and a degradable fiber upper net provided on the second composite matrix layer.

[0010] Preferably, the water-soluble lower film is a PVA resin matrix film. The first composite matrix layer has a multi-layer network structure and is made of 98% natural plant coconut shell fiber and 2% decomposed product of pea straw. The thickness of the natural plant coconut shell fiber is 0.8 cm - 1.2 cm.

[0011] Preferably, the organic fertilizer mixture particle layer at least includes organic fertilizer, green manure crude fiber, starch binder, and compound microbial fertilizer. The water-soluble upper film is a PVA resin matrix film.

[0012] Preferably, the green manure crude fiber at least includes crushed pea straw. The mass ratio of the organic fertilizer, green manure crude fiber, and compound microbial fertilizer is 1:(1.5 - 2.0):(0.3 - 0.5).

[0013] Preferably, the degradable fiber lower net is made of polylactic acid degradation material. The composite seed belt includes a water-soluble PVA film and a gel film sequentially provided on the degradable fiber lower net, and grass seeds are provided between the water-soluble PVA film and the gel film.

[0014] Preferably, the gel film is a water-retaining and slow-release nitrogen fertilizer nano-composite gel film, which at least includes sodium alginate, sodium carboxymethylcellulose, acid-activated montmorillonite, and urea.

[0015] Preferably, the second composite matrix layer is a composite matrix layer mixed with coconut shell fiber and pea straw. The degradable fiber upper net is made of polylactic acid degradation material.

[0016] Preferably, a soil anchoring assembly is further provided at the end of the ecological grass carpet, and the soil anchoring assembly is used to fix the ecological grass carpet to the soil surface.

[0017] On the other hand, the present invention proposes a method for constructing a slow-release ecological grass carpet for improving eroded and infertile land, including the following steps:

[0018] Select the eroded and infertile land soil surface to be improved, remove the obstacles on the soil surface and level the soil surface. According to the preset requirements, trim a number of partitions along the contour direction on the soil surface, where the width of the partition is 10 cm - 15 cm, and the distance between the partitions is 3 m - 5 m;

[0019] Prepare the bottom interception layer, nutrient slow-release layer, seed triggering layer, and surface fixing layer and bond them to form a carpet body. Bury one end of the carpet body into one end of the partition and unfold the carpet body towards the other end of the partition, so that the seed triggering layer in the carpet body is parallel to the contour;

[0020] Fix the end face of the blanket body, cover the soil after laying, and manually press to make the blanket body fully contact with the soil surface. Water the blanket body until it is thoroughly soaked to dissolve the water-soluble upper film, water-soluble lower film, and composite seed belt, so as to release the nutrients in the nutrient slow-release layer and the seeds in the composite seed belt.

[0021] Water evenly at least twice a day to keep the soil moist, and gradually reduce the watering frequency according to the growth situation until the ecological grass blanket meets the preset requirements.

[0022] Preferably, the composite seed belt includes a water-soluble PVA film and a gel film sequentially arranged on the degradable fiber lower net. The gel film at least includes sodium alginate, sodium carboxymethylcellulose, acid-activated montmorillonite, and urea. The steps for preparing the seed trigger layer include:

[0023] Disperse sodium alginate and sodium carboxymethylcellulose evenly in deionized water according to a preset mass ratio. Add glycerol as a plasticizer to the dispersed solution and then conduct a first stirring and mixing to obtain a mixed solution.

[0024] Perform ultrasonic bath dispersion treatment on the acid-activated montmorillonite, add the dispersed solution after ultrasonic dispersion treatment to the mixed solution and then conduct a second stirring and mixing. Use a pear-shaped separating funnel to dropwise add calcium chloride solution as an ionic crosslinking agent to the mixed solution after the second stirring and mixing, and keep stirring during the dropping process.

[0025] Add urea to the solution after dropping and keep stirring to form a homogeneous gel solution. Perform ultrasonic treatment on the homogeneous gel solution to remove air bubbles, pour the homogeneous gel solution after removing air bubbles into a glass petri dish for drying to obtain the gel film.

[0026] Select grass seeds, disinfect, rinse, drain once, soak with medicine, and drain twice the grass seeds. Place the grass seeds after the second draining between the gel film and the water-soluble PVA film, and make them adhere to each other by the self-adhesion between the materials to form a composite seed belt.

[0027] Attach the prepared composite seed belt to the degradable fiber lower net to form the seed trigger layer.

[0028] Advantages of the present application: The slow-release ecological grass carpet for improving eroded and infertile land provided by the present application includes a bottom interception layer, a nutrient slow-release layer, a seed triggering layer, and a surface fixation layer sequentially arranged on the surface of the eroded and infertile land; the bottom interception layer and the surface fixation layer can form a full-coverage protection for the soil surface, reduce the average runoff rate, reduce the soil loss rate, and reduce the soil erosion rate, having the function of erosion resistance, and can provide a favorable growth environment for the initial stage of plant growth, enabling the plants in the lower seed triggering layer to grow rapidly through the coconut fiber - pea straw composite matrix layer, and the degradation in the later stage can be converted into nutrients; the nutrient slow-release layer can dissolve the water-soluble upper film by watering, release the fertilizer in the organic fertilizer mixture particle layer, and slowly release the fertilizer by gravity, reducing the number of fertilization times and matching the vegetation growth cycle. The organic fertilizer particles and green manure crude fibers in the nutrient slow-release layer release nutrients through microbial degradation to achieve continuous fertilization in the later stage of plant growth; in the seed triggering layer, the seeds are placed in the composite seed belt, changing the flat sowing layer to a multi-functional seed belt to achieve precise seeding of the seeds. By combining the characteristics of the hydrogel material, the fertilizer and a large amount of water are retained, and water and nutrients are provided for the initial stage of plant growth in a continuous and slow manner; the ecological grass carpet provided by the present application has high seed survival rate, good uniformity, low cost, and can achieve sustainable ecological restoration, and is suitable for large-scale promotion.

[0029] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Brief Description of the Drawings

[0030] Figure 1 Schematic diagram of the ecological grass carpet provided by the present invention arranged on a slope;

[0031] Figure 2 is Figure 1 exploded schematic diagram of each layer structure of the ecological grass carpet in

[0032] Figure 3 is Figure 2 exploded schematic diagram of the bottom interception layer and the nutrient slow-release layer in

[0033] Figure 4 is Figure 2 schematic diagram of the seed triggering layer in

[0034] Figure 5 is Figure 4 schematic diagram of the composite seed belt in

[0035] Figure 6 is Figure 2 schematic diagram of the surface fixation layer in

[0036] Main reference numerals;

[0037] 10. Bottom interception layer; 11. Water-soluble lower film; 12. First composite matrix layer; 20. Nutrient slow-release layer; 21. Organic fertilizer mixture particle layer; 22. Water-soluble upper film; 30. Seed trigger layer; 31. Degradable fiber lower net; 32. Composite seed belt; 321. Water-soluble PVA film; 322. Gel film; 323. Grass seeds; 40. Surface fixation layer; 41. Second composite matrix layer; 42. Degradable fiber upper net; 50. Soil anchoring component.

[0038] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. Specific embodiments

[0039] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0041] Specifically, please refer to Figures 1 - 6 , the slow-release ecological grass carpet for improving eroded badlands provided by the present application includes a bottom interception layer 10, a nutrient slow-release layer 20, a seed trigger layer 30, and a surface fixation layer 40 sequentially arranged on the eroded badland soil surface; further, as Figure 2 and Figure 3 shown, the bottom interception layer 10 at least includes a water-soluble lower film 11 provided on the soil surface and a first composite matrix layer 12 provided on the water-soluble lower film 11; the nutrient slow-release layer 20 at least includes an organic fertilizer mixture particle layer 21 provided on the first composite matrix layer 12 and a water-soluble upper film 22 provided on the organic fertilizer mixture particle layer 21; the seed trigger layer 30 includes a degradable fiber lower net 31 provided on the water-soluble upper film 22 and a composite seed belt 32 provided on the degradable fiber lower net 31; the surface fixation layer 40 includes a second composite matrix layer 41 provided on the composite seed belt 32 and a degradable fiber upper net 42 provided on the second composite matrix layer 41.

[0042] Optionally, in this application, the seed triggering layer 30 is placed on the nutrient slow-release layer 20, and the grass seeds are located within the seed triggering layer 30, forming a slow-release ecological grass carpet suitable for improving the infertile land of red soil erosion in the south; the nutrient slow-release layer 20 includes a water-soluble upper film. After the grass carpet is laid on the soil surface, watering can dissolve the water-soluble upper film, and the fertilizer in the organic fertilizer mixture particle layer is released. Through gravity, the fertilizer is slowly released, reducing the number of fertilization times and matching the vegetation growth cycle. The composite seed belt in the seed triggering layer will also release grass seeds during the watering process. The fertilizer is located below the seeds, providing conditions for seed germination and growth in places where plants are difficult to grow during the restoration of eroded wasteland or the slope protection of newly built orchards; the seed triggering layer in the grass carpet can be made into a corresponding seed belt according to the optimal seeding density of the target seeds; a bottom interception layer 10 is laid below the nutrient slow-release layer 20 to reduce soil erosion caused by direct rainwater scouring of the soil surface; a surface fixing layer 40 is laid above the seed triggering layer 30. The seed triggering layer 30 includes a degradable fiber lower net, which can reduce the direct scouring of rainwater on the seeds, reduce seed loss and uneven distribution, reduce the number of reseeding times, and improve the vegetation survival rate; the materials used in each structural layer of this application are all degradable biological materials, with low cost and environmental friendliness; it can be used for both flat land restoration and slope land restoration. The bottom interception layer 10 and the surface fixing layer 40 can provide full coverage protection for the soil surface, reduce the average runoff rate, reduce the soil loss rate, lower the soil erosion rate, have the function of erosion resistance, and can provide a favorable growth environment for the initial stage of plant growth, enabling the plants in the lower seed triggering layer to grow rapidly through the coconut fiber - pea straw composite matrix layer, and the later degradation can be converted into nutrients.

[0043] Optionally, in this application, the water-soluble lower film in the bottom interception layer 10 is a PVA (polylactic acid) resin matrix film, which does not affect seed germination and growth. The PVA material can be gradually degraded to form humus, avoiding pollution; the first composite matrix layer is a multi-layer network structure, specifically a coconut fiber - pea straw composite matrix layer, and is made of 98% natural plant coconut fiber and 2% pea straw decomposition products. The thickness of the natural plant coconut fiber is 0.8 cm - 1.2 cm; preferably, the thickness of the coconut coir mat is 1 cm.

[0044] Optionally, in the present application, the water-soluble upper film in the nutrient slow-release layer 20 is similar to the water-soluble lower film material and is also a PVA resin matrix film; the organic fertilizer mixture particle layer at least includes organic fertilizer, green manure crude fiber, starch binder, and compound microbial fertilizer; the green manure crude fiber at least includes pea straw powder; the mass ratio of the organic fertilizer, green manure crude fiber, and compound microbial fertilizer is 1:(1.5 - 2.0):(0.3 - 0.5), the organic matter content of the organic fertilizer is 265 g / kg, the organic matter content of the green manure is 687 g / kg, and the nutrient ratio of nitrogen, phosphorus, potassium, and organic matter in the compound microbial fertilizer is: 6:3:4:30 - 7:4:5:35; preferably, the mass ratio of the organic fertilizer, green manure crude fiber, and compound microbial fertilizer is 1:1.8:0.36, and the nutrient ratio of nitrogen, phosphorus, potassium, and organic matter in the compound microbial fertilizer is: 6.3:3.5:4.2:32; the nutrient slow-release layer 20 contains slow-release nutrients, and the water-soluble film dissolves in water to release the wrapped coconut fiber - pea straw composite matrix layer and organic fertilizer mixed particles.

[0045] Optionally, in the present application, the degradable fiber lower net in the seed trigger layer 30 is made of polylactic acid degradable material, such as Figure 4 and Figure 5 shown, the composite seed belt 32 includes a water-soluble PVA film 321 and a gel film 322 arranged in sequence on the degradable fiber lower net, and grass seeds 323 are arranged between the water-soluble PVA film 321 and the gel film 322; further, the gel film is a water-retaining slow-release nitrogen fertilizer nano-composite gel film (SA / CMC / AMMT-Urea), which at least includes sodium alginate (SA), sodium carboxymethylcellulose ((Na-CMC), acid-activated montmorillonite (AMMT), and urea (Urea); specifically in use, trenches are dug on the existing soil surface, and this ecological grass carpet is laid. After saturated irrigation, the water-soluble film part in the carpet will dissolve in water, releasing the wrapped water-retaining slow-release nitrogen fertilizer nano-composite gel film, seeds, and the nutrient slow-release part and the bottom coconut fiber - pea straw composite matrix layer. Each component fully absorbs water and falls under gravity to provide conditions for seed germination and growth in places where plants are difficult to grow during the restoration of eroded wasteland or the slope protection of newly built orchards, enhancing erosion resistance and ecological stability; the grass seeds can be selected as local pioneer grass seeds, and the seed dormancy is broken according to the seed characteristics.

[0046] Optionally, in the present application, the second composite matrix layer 41 in the surface fixing layer 40 is made of the same material as the first composite matrix layer 12, which is also a composite matrix layer mixed with coconut shell fibers and pea straws. The biodegradable fiber upper net 42 and the biodegradable fiber lower net 31 are made of the same material and are also made of polylactic acid degradation materials. Optionally, the surface fixing layer 40 and the seed triggering layer 30 can fix the biodegradable fiber upper net 42 and the biodegradable fiber lower net 31 through a hot pressing composite process, and the overall ecological grass blanket can achieve structural stability through quilting reinforcement and layered lamination.

[0047] Furthermore, in some optional embodiments, in order to improve the fixing effect of the ecological grass blanket, a soil anchoring assembly 50 is also provided at the edge of the ecological grass blanket. The soil anchoring assembly 50 can use local materials, such as woody plant branches (such as willow branches and poplar branches), etc., and U-shaped nails are used for fixing during steep slope construction.

[0048] The present application also provides a construction method for a slow-release ecological grass blanket for improving eroded and infertile lands; the specific construction process is as follows:

[0049] S10, select the eroded and infertile land surface to be improved, remove the obstacles on the surface and level the surface, and trim a number of partitions along the contour direction on the surface according to preset requirements, where the width of the partitions is 10 cm - 15 cm and the distance between the partitions is 3 m - 5 m;

[0050] The obstacles mainly include surface sundries, stones, tree roots, etc., to ensure that the ecological grass blanket fits tightly with the surface without gaps and reduce stress concentration during water flow scouring; 60% of the trimmed soil is used for trimming the partitions, and 40% is used for covering the soil after laying the blanket body.

[0051] S20, prepare the bottom interception layer, nutrient slow-release layer, seed triggering layer and surface fixing layer and laminate them to form a blanket body, bury one end of the blanket body into one end of the partition, and unfold the blanket body towards the other end of the partition, so that the seed triggering layer in the blanket body is parallel to the contour;

[0052] Among them, the steps for preparing the seed triggering layer include:

[0053] Disperse sodium alginate (SA) and sodium carboxymethylcellulose (Na-CMC) in deionized water according to a preset mass ratio, add glycerol as a plasticizer to the dispersed solution and then perform a first stirring and mixing to obtain a mixed solution; in the present application, the preset mass ratio is 1:1; the deionized water is 25 ml, and the glycerol is 30 wt% glycerol; the stirring conditions are continuous magnetic stirring at 60 °C and 300 rpm for 2 h. A 2% concentration uniform mixed solution is obtained.

[0054] The acid-activated montmorillonite was dispersed by ultrasonic bath treatment. The dispersion after ultrasonic dispersion treatment was added to the mixed solution and then stirred and mixed again. A calcium chloride solution was added dropwise as an ionic crosslinking agent to the mixed solution after the second stirring and mixing using a pear-shaped separatory funnel, and stirring was maintained during the dropping process; in this application, 10 ml of the acid-activated montmorillonite (AMMT) dispersion dispersed by ultrasonic bath (3 min, 40 Hz) was slowly added to the mixed solution, and stirring was continued for 30 min at 25 °C and 500 rpm to ensure thorough mixing; after the solution was mixed evenly, 25 ml of a 0.64 mg / mL calcium chloride solution was slowly added dropwise to the continuously stirred mixed solution using a pear-shaped separatory funnel.

[0055] Urea was added to the solution after the dropping was completed and stirring was maintained to form a homogeneous gel solution. The homogeneous gel solution was ultrasonically treated to remove air bubbles. The homogeneous gel solution after removing air bubbles was poured into a glass petri dish and dried to obtain the gel film; in this application, after the dropping was completed, 10 wt% urea (Urea) was added to the gel solution, and stirring was continued for 3 h to form a homogeneous gel solution. Then, the gel solution was ultrasonically treated in an ultrasonic bath (3 min, 40 Hz) to remove air bubbles. Finally, the film-forming solution was poured into a glass petri dish and dried in an air oven at 50 °C for 24 h to obtain the SA / CMC / AMMT-Urea water-retaining and slow-release nitrogen fertilizer nanocomposite gel film (SCAMU); the water-retaining and slow-release nitrogen fertilizer nanocomposite gel film can absorb more than 100 times its own weight of water, and the degradation rate within 20 days is 49%, showing good biodegradability and environmental stability.

[0056] Grass seeds were selected and subjected to disinfection, rinsing, primary draining, medicament soaking, and secondary draining treatments. The grass seeds after secondary draining were placed between the gel film and the water-soluble PVA film, and a composite seed tape was made by relying on the self-adhesion between the materials;

[0057] The seeds can be local pioneer grass seeds, etc. The seed dormancy was broken according to the seed characteristics. Taking Cynodon dactylon as an example, dehulled Cynodon dactylon seeds can be disinfected by shaking with a 10% sodium hypochlorite solution for 30 min, rinsed 5 - 6 times with distilled water after disinfection, drained the surface moisture, and then soaked the seeds with the test medicament (4000-fold 28-higher brassinolide·gibberellic acid A4 + 7 soluble concentrate) at room temperature for 12 h, drained the surface moisture, and then placed them in the seed tape; taking Echinochloa crusgalli seeds as an example, they can be soaked with 30 mg / L cinnamamide and its quaternary ammonium salt medicament and then drained the surface moisture and placed in the seed tape.

[0058] The prepared composite seed tape was laminated with a degradable fiber lower net to form the seed trigger layer.

[0059] S30. Fix the end face of the blanket body, cover the soil after laying, and gently press it manually to make the blanket body fully contact with the soil surface. Water the blanket body thoroughly to dissolve the water-soluble upper film, water-soluble lower film, and composite seed belt, so as to release the nutrients in the nutrient slow-release layer and the seeds in the composite seed belt.

[0060] At the top of the slope, bury the blanket body in the intercepting drain or soil, with a burial depth of 20 - 40 cm. Unroll the blanket body from the top of the slope downward, ensuring that the seed belt in the ecological grass blanket is parallel to the contour line. When laying, it is necessary to tighten it without wrinkles. The overlapping width between the blanket bodies should be ≥ 10 cm, and it is fixed with soil anchoring components (the spacing at the top of the slope is 70 cm, and the spacing on the slope surface is about 1 m). Cover the soil after laying, and gently press it manually to make the blanket body fully contact with the soil, improving the germination rate of grass seeds. For the initial wetting, water it thoroughly to dissolve the PVA film and trigger the gel water-retaining seed belt and fertilizer release.

[0061] S40. Water evenly at least twice a day to keep the soil moist, and gradually reduce the watering frequency according to the growth situation until the ecological grass blanket meets the preset requirements.

[0062] Check whether the fixation is firm and whether the fit degree between the blanket body and the slope surface meets the standard (no bulges or wrinkles). In the initial stage, water twice a day (before 10 am and after 4 pm), spray evenly to keep the soil moist, and gradually reduce the watering frequency according to the growth situation. After 3 months, it grows naturally.

[0063] To verify the effect of the ecological grass blanket provided by this application, the following experiments were carried out;

[0064] I. Seed germination and seedling growth experiment of the composite seed belt in the seed trigger layer

[0065] In this experiment, Shanghaiqing seeds were used for pot experiments, and a blank group, a control group, and an experimental group were set up; in the blank group, Shanghaiqing seeds were directly sown into the pots; in the control group, Shanghaiqing seeds were placed between the water-soluble PVA film and the gel film, but the gel film did not contain urea to form a control seed belt, and then the control seed belt was put into the pots for sowing; in the experimental group, Shanghaiqing seeds were placed between the water-soluble PVA film and the gel film, and the gel film was a composite seed belt formed by the water-retaining and slow-release nitrogen fertilizer nano-composite gel film (SA / CMC / AMMT-Urea) provided by this application, and then the composite seed belt was put into the pots for sowing; during the three groups of experiments, except for the different seed treatment processes in the pots, other conditions were the same; the fresh weight of the seedlings was counted 7 days after sowing; the statistical results are shown in Table 1;

[0066] Table 1

[0067] Group Number Fresh weight of seedlings after 7 days / g Increase percentage compared to CK Blank group CK 0.1567 0 Control group SCAM 0.183 16.8 Experimental group SCAMU 0.23 45.8

[0068] As can be seen from Table 1, for the composite seed tape provided in this application, the seeds are placed between a water-soluble PVA film and a gel film, and the gel film is a water-retaining and slow-release nitrogen fertilizer nano-composite gel film. The fresh weight of the plant seedlings after 7 days is significantly higher than that of the blank group, which proves that the composite seed tape in this blanket can effectively improve the growth effect of the seedlings after seed germination.

[0069] II. Experiment on the influence of the nutrient slow-release layer on the soil surface nutrients

[0070] In this experiment, bermudagrass seeds were used, and the red soil developed from granite was used as the test soil for outdoor experiments. A blank group, five control groups and an experimental group were set up to test the nutrient conditions in the test soil and estimate the number of days when the vegetation coverage reached 80%. It should be noted that the number of days required to reach 80% coverage in this application was calculated according to the destructive sampling method at 100% coverage and the geometric growth rate, rather than the actual growth days. The blank group does not contain a nutrient layer, and the experimental group contains the nutrient slow-release layer provided in this application. The organic fertilizer mixture particle layer in the nutrient slow-release layer includes organic fertilizer, green manure crude fiber, starch binder and compound microbial fertilizer; the nutrient layer in Control Group 1 is: biochar + green manure; the nutrient layer in Control Group 2 is: biochar + organic fertilizer; the nutrient layer in Control Group 3 is: biochar; the nutrient layer in Control Group 4 is: organic fertilizer; the nutrient layer in Control Group 5 is: green manure. Except for the different nutrient layers, the blank group, the control groups and the experimental group have the same other conditions; the experimental results are shown in Table 2:

[0071]

[0072] As can be seen from Table 2, the blank group cannot reach 80% vegetation coverage, and the nutrient slow-release layer provided in this application can effectively reduce the time to reach 80% vegetation coverage; in addition, it has a certain effect on improving soil pH, increasing total nitrogen, organic matter, fiber enzyme, phosphatase, urease, etc. in the soil, and the comprehensive improvement situation is the best; the nutrient slow-release layer can quickly increase the change of early vegetation coverage, significantly improve problems such as red soil acidification and low fertility, thereby enhancing the productivity and ecological function of red soil.

[0073] In summary, the slow-release ecological grass carpet for improving eroded badlands provided by the present application, based on the conventional plant fiber carpet, adopts a multi-layer slow-release collaborative control technology to achieve the effects of water retention and fertilizer control in the seed triggering layer, stage-by-stage fertilizer supply in the nutrient slow-release layer, and dynamic sediment interception in the upper and lower carpet layers; specifically, it includes a bottom interception layer, a nutrient slow-release layer, a seed triggering layer, and a surface fixing layer that are sequentially arranged on the eroded badland soil surface; the bottom interception layer 10 and the surface fixing layer 40 can form a full-coverage protection for the soil surface, reduce the average runoff rate, reduce the soil loss rate, lower the soil erosion rate, have the function of erosion resistance, and can provide a favorable growth environment for the initial stage of plant growth, enabling the plants in the lower seed triggering layer to grow rapidly through the coconut fiber - pea straw composite matrix layer, and the degradation in the later stage can be converted into nutrients; in the nutrient slow-release layer 20, watering can dissolve the water-soluble upper film, and the fertilizer in the organic fertilizer mixture particle layer is released, and through gravity, the fertilizer is slowly released, reducing the number of fertilization times and matching the vegetation growth cycle. In the nutrient slow-release layer 20, the organic fertilizer particles and the green manure coarse fiber release nutrients through microbial degradation to achieve continuous fertilizer supply in the later stage of plant growth; in the seed triggering layer 30, the seeds are placed in the composite seed belt, and the flat sowing layer is changed to a multi-functional seed belt to achieve precise seeding of the seeds. By combining the characteristics of the hydrogel material, the fertilizer and a large amount of water are retained, and water and nutrients are provided for the initial stage of plant growth in a continuous and slow manner; the ecological grass carpet provided by the present application has high seed survival rate, good uniformity, low cost and can achieve sustainable ecological restoration, and is suitable for large-scale promotion.

[0074] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0075] The above-described embodiments only represent several implementation manners of the present application. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A slow-release ecological grass carpet for improving eroded badlands, characterized in that, It includes a bottom interception layer, a nutrient slow-release layer, a seed triggering layer, and a surface fixation layer that are sequentially arranged on the eroded badland soil surface; The bottom interception layer at least includes a water-soluble lower film arranged on the soil surface and a first composite matrix layer arranged on the water-soluble lower film; The nutrient slow-release layer at least includes an organic fertilizer mixture particle layer arranged on the first composite matrix layer and a water-soluble upper film arranged on the organic fertilizer mixture particle layer; The seed triggering layer includes a degradable fiber lower net arranged on the water-soluble upper film and a composite seed belt arranged on the degradable fiber lower net; The surface fixation layer includes a second composite matrix layer arranged on the composite seed belt and a degradable fiber upper net arranged on the second composite matrix layer.

2. The slow-release ecological grass carpet for improving eroded badlands according to claim 1, wherein The water-soluble lower film is a PVA resin matrix film, the first composite matrix layer has a multi-layer mesh structure and is made of 98% natural plant coconut shell fiber and 2% decomposed product of pea straw, and the thickness of the natural plant coconut shell fiber is 0.8 cm - 1.2 cm.

3. The slow-release ecological grass carpet for improving eroded badlands according to claim 1, characterized in that, The organic fertilizer mixture particle layer at least includes organic fertilizer, green manure crude fiber, starch binder, and composite microbial fertilizer, and the water-soluble upper film is a PVA resin matrix film.

4. The slow-release ecological grass carpet for improving eroded badlands according to claim 3, characterized in that, The green manure crude fiber at least includes crushed pea straw, and the mass ratio of the organic fertilizer, green manure crude fiber, and composite microbial fertilizer is 1:(1.5 - 2.0):(0.3 - 0.5).

5. The slow-release ecological grass carpet for improving eroded badlands according to claim 1, wherein The degradable fiber lower net is made of polylactic acid degradation material, and the composite seed belt includes a water-soluble PVA film and a gel film that are sequentially arranged on the degradable fiber lower net, and grass seeds are arranged between the water-soluble PVA film and the gel film.

6. The slow-release ecological grass carpet for improving eroded badlands according to claim 5, characterized in that, The gel film is a water-retaining and slow-release nitrogen fertilizer nano-composite gel film, and at least includes sodium alginate, sodium carboxymethylcellulose, acid-activated montmorillonite, and urea.

7. The slow-release ecological grass carpet for improving eroded badlands according to claim 1, characterized in that, The second composite matrix layer is a composite matrix layer mixed with coconut shell fiber and pea straw, and the degradable fiber upper net is made of polylactic acid degradation material.

8. The slow-release ecological grass carpet for improving eroded badlands according to claim 1, characterized in that, The end of the ecological grass blanket is also provided with a soil anchoring component, and the soil anchoring component is used to fix the ecological grass blanket to the soil surface.

9. A method for constructing a slow-release ecological grass carpet for improving eroded badlands according to any one of claims 1-8, characterized in that, It includes the following steps: Select the eroded badland soil surface to be improved, remove the obstacles on the soil surface and level the soil surface, and trim a number of partitions on the soil surface along the contour direction according to the preset requirements, where the width of the partition is 10 cm - 15 cm, and the distance between partitions is 3 m - 5 m; Prepare the bottom interception layer, nutrient slow-release layer, seed triggering layer, and surface fixation layer and bond them to form a blanket body, bury one end of the blanket body into one end of the partition, and unfold the blanket body towards the other end of the partition so that the seed triggering layer in the blanket body is parallel to the contour; Fix the end face of the blanket body, cover the soil after laying, manually press to make the blanket body fully contact with the soil surface, water the blanket body and water it thoroughly to dissolve the water-soluble upper film, water-soluble lower film, and composite seed belt to release the nutrients in the nutrient slow-release layer and the seeds in the composite seed belt; Water evenly at least twice a day to keep the soil moist, and gradually reduce the watering frequency according to the growth situation until the ecological grass blanket meets the preset requirements.

10. The construction method of the slow-release ecological grass carpet for improving eroded badlands according to claim 9, characterized in that, The composite seed belt includes a water-soluble PVA film and a gel film which are sequentially arranged on the degradable fiber lower net. The gel film at least includes sodium alginate, sodium carboxymethylcellulose, acid-activated montmorillonite and urea. The steps for preparing the seed trigger layer include: Uniformly disperse sodium alginate and sodium carboxymethylcellulose in deionized water according to a preset mass ratio. After adding glycerol as a plasticizer to the dispersed solution, perform a first stirring and mixing to obtain a mixed solution; Perform ultrasonic bath dispersion treatment on the acid-activated montmorillonite. Add the dispersed solution after ultrasonic dispersion treatment to the mixed solution and then perform a second stirring and mixing. Use a pear-shaped separatory funnel to dropwise add a calcium chloride solution as an ionic crosslinking agent to the mixed solution after the second stirring and mixing, and keep stirring during the dropping process; Add urea to the solution after dropping and keep stirring to form a homogeneous gel solution. Perform ultrasonic treatment on the homogeneous gel solution to remove air bubbles. Pour the homogeneous gel solution after removing air bubbles into a glass petri dish for drying to obtain the gel film; Select grass seeds, disinfect, rinse, drain for the first time, soak with a medicament, and drain for the second time the grass seeds. Place the grass seeds drained for the second time between the gel film and the water-soluble PVA film, and make a composite seed belt by adhering relying on the self-adhesion between the materials; Adhere the prepared composite seed belt to the degradable fiber lower net to form the seed trigger layer.

Images