Method for ecological restoration of high and cold degraded grassland

Abstract

The invention provides an ecological restoration method for alpine degraded grassland, and belongs to the technical field of ecological restoration. According to the method, planting soil, water, mixed grass seeds containing gramineous plants and leguminous plants, moss spore powder, a water-retaining agent, an adhesive, a compound fertilizer and an organic fertilizer are mixed to prepare a soil dressing spray-seeding agent, spray-seeding is carried out on the grassland slope with the temperature smaller than or equal to 20 DEG C, non-woven fabric covers the grassland slope after spray-seeding, and rapid repairing of the high-altitude, high-cold and high-radiation grassland slope in Qinghai and Tibet is achieved. All the materials are environment-friendly materials, can be degraded under natural conditions, do not cause pollution to the environment, and have important significance on restoration of grassland slope ecology in the Qinghai-Tibet alpine region.

Description

Technical Field

[0001] The present invention relates to the technical field of ecological restoration, and in particular to a method for ecological restoration of alpine degraded grasslands. Background Art

[0002] Alpine steppe is a plant community that is affected by cold and drought climate for a long time in high altitude areas. It is composed of cold-resistant and drought-resistant perennial dense grasses, rhizomatous sedges and cushion-shaped small semi-shrubs as the dominant species.

[0003] The alpine plateau is a fragile ecosystem of global significance. As one of the important pastoral areas in my country, its grassland area is vast, accounting for about 50.9% of the total area of ​​the Qinghai-Tibet Plateau. The complex biodiversity and unique geographical environment and cultural characteristics provide guarantees for local life and economic development. However, in recent years, due to human factors and changes in the natural climate (drought, low temperature), the already fragile alpine grassland has experienced varying degrees of degradation. Therefore, how to shorten the cycle of ecological restoration and achieve vegetation restoration, carbon fixation and erosion control in a short period of time has become a key issue that needs to be solved urgently.

[0004] The spraying technology uses water as a carrier to mix and stir the technologically processed plant seeds, fiber coverings, adhesives, water-retaining agents and nutrients required for plant growth through a sprayer and spray them to the desired planting location, thus forming a greening technology for primary ecological vegetation.

[0005] However, due to the climate characteristics of high cold, high drought, strong winds, and strong sunshine (high radiation) in high altitude areas, the ecosystems formed are extremely fragile. Plants are difficult to survive after spraying, and the natural recovery process after damage is even longer. Therefore, it is urgent to shorten the greening process through artificial intervention, form a stable plant community as soon as possible, and restore the health and safety of the ecological barrier in the high altitude areas of Qinghai and Qinghai-Tibet. Summary of the invention

[0006] In view of this, the present invention provides a method for ecological restoration of alpine degraded grasslands, which realizes the ecological restoration of alpine degraded grasslands in the Qinghai-Tibet region through foreign soil spraying + biological crust + non-woven fabric covering.

[0007] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0008] The present invention provides an ecological restoration method for alpine degraded grassland, comprising the following steps:

[0009] S1. Collect moss crusts on the slopes of alpine grassland meadows;

[0010] S2. Spread the obtained crust fragments in a ventilated place and dry them in the shade for 45 to 50 hours, then crush them to make the primary generation moss propagation material;

[0011] S3. The primary moss propagation material is mixed with peat soil, spread flat for cultivation, to obtain moss, and the stems are broken and crushed to make moss spore powder;

[0012] S4. Mix planting soil, water, mixed grass seeds, moss spore powder, water retaining agent, adhesive, compound fertilizer and organic fertilizer to make a soil spraying agent, and spray it on the grassland slope ≤20°;

[0013] S5. Cover the soil with non-woven fabric after spraying and water 1 to 2 times a week within three months from spraying.

[0014] Preferably, the soil-added spraying agent includes the following components in parts by mass: 3000-3400 parts of planting soil, 2500-2900 parts of water, 2.2-3.9 parts of grass seeds, 2-5 parts of water retaining agent, 10-13 parts of adhesive, 7-11 parts of compound fertilizer, and 200-300 parts of organic fertilizer.

[0015] Preferably, the grass seeds include Elymus nutans seeds, Poa brevifolia seeds and Astragalus obliquus seeds; the mass ratio of the Elymus nutans seeds, Poa brevifolia seeds and Astragalus obliquus seeds is 0.9-1.8:0.6-1.2:0.7-0.9.

[0016] Preferably, the water retaining agent includes polyacrylamide, and the binder includes starch.

[0017] Preferably, the spraying amount of the foreign soil spraying agent is 5721.2-6632.9 g / m 2 .

[0018] Preferably, the moss crust layer is collected from June to August on the Qinghai-Tibet Plateau, and the thickness of the moss crust layer is 0.5 to 2 cm.

[0019] Preferably, the moss crust layer includes mosses including Bryum fasciatum and Bryum fasciatum.

[0020] Preferably, the mixing mass ratio of the primary moss propagation material to the peat soil is 1:3.5-4.5, and during the culture process, the Knop culture medium nutrient mother solution with a concentration of 38-42% is sprayed at a frequency of 8-12 days / time; and pure water is poured once every 3 days.

[0021] Preferably, the non-woven fabric is a degradable non-woven fabric with a mass per unit area of ​​18 to 22 g / m 2 .

[0022] By adopting the above technical solution, the present invention has the following beneficial effects:

[0023] (1) The soil spraying restoration method of the present invention can be applied to alpine grassland slopes with a slope of ≤20°.

[0024] (2) The addition of biocrusts and non-woven fabric covering can effectively retain soil water and prevent erosion, especially in the initial restoration of severely degraded grasslands. The spraying of imported soil can effectively overcome the adverse conditions of the original soil, quickly restore vegetation and improve soil conditions.

[0025] (3) Soil spraying has the advantage of uniform laying. Compared with traditional row sowing and broadcast sowing, the mixture of fertilizers and grass seeds can improve fertilizer utilization and germination rate, optimize resource utilization and save restoration costs.

[0026] (4) All materials of the present invention are environmentally friendly materials that can be degraded under natural conditions and will not cause pollution to the environment.

[0027] (5) The present invention has achieved initial success in the Qinghai-Tibet Experimental Area and is a national key project. It is of great significance to the restoration of grassland slope ecology in the Qinghai-Tibet alpine region. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is the effect diagram of each group of spraying schemes on soil moisture content. Different lowercase letters indicate significant differences among treatments (P<0.05), the same below.

[0029] Figure 2 Statistical chart of soil bulk density in each experimental group.

[0030] Figure 3 Statistical chart of biomass of each experimental group.

[0031] Figure 4 Statistical chart of crust coverage for each experimental group.

[0032] Figure 5 Statistical chart of total plant cover in each experimental group.

[0033] Figure 6 This is a statistical chart of plant coverage in each experimental group.

[0034] Figure 7 Statistical chart of the total plant density in each experimental group.

[0035] Figure 8 Statistical chart of plant density in each experimental group.

[0036] Fig. 9 It is a statistical chart of the total height (average height) of plants in each experimental group.

[0037] Fig.10 This is a statistical chart of the height of plants in each experimental group.

[0038] Fig.11 Statistical chart of soil erosion values ​​in each experimental group. DETAILED DESCRIPTION

[0039] The present invention provides an ecological restoration method for alpine degraded grassland, which is characterized by comprising the following steps:

[0040] S1. Collect moss crusts on the slopes of alpine grassland meadows;

[0041] S2. Spread the obtained crust fragments in a ventilated place and dry them in the shade for 45 to 50 hours, then crush them to make the primary generation moss propagation material;

[0042] S3. The primary moss propagation material is mixed with peat soil, spread flat for cultivation, to obtain moss, and the stems are broken and crushed to make moss spore powder;

[0043] S4. Mix planting soil, water, mixed grass seeds, moss spore powder, water retaining agent, adhesive, compound fertilizer and organic fertilizer to make a soil spraying agent, and spray it on the grassland slope ≤20°;

[0044] S5. Cover the soil with non-woven fabric after spraying and water 1 to 2 times a week within three months from spraying.

[0045] In the present invention, firstly, the foreign soil is collected. Considering the transportation cost, it is preferred to select the local soil with good fertility. After removing the larger gravel, roots and other debris, the soil is passed through a 4mm sieve to remove the hard soil blocks in the soil. The soil is air-dried in a cool place for 48 hours for use as planting soil.

[0046] In the present invention, after completing the collection of foreign soil, the moss raw materials are collected and propagated. The moss raw materials are collected from June to August on the Qinghai-Tibet Plateau. Since the temperature and precipitation at this time are suitable for moss growth, it is easier to collect them on the shady side of the slope of the alpine grassland meadow. When collecting, it is preferred to use a hand shovel or a small iron hoe to take the moss crust layer. The thickness of the moss crust layer is 0.5 to 2 cm, more preferably 0.8 to 1.7 cm, and more preferably 1.5 cm; the moss is preferably a local variety, including clustered true moss and northern tooth moss.

[0047] When processing moss materials, the present invention first spreads the obtained crust layer fragments in a ventilated place to dry in the shade, removes impurities, and crushes them to make primary moss propagation materials; the drying time is 46 to 50 hours, more preferably 47 to 49 hours, and more preferably 48 hours; the crushing is preferably crushed by a plant crusher, and the crushing time is 25 to 35 seconds, more preferably 28 to 32 hours, and more preferably 30 hours. In the present invention, after the primary moss propagation materials are made, the moss is further cultured. First, non-woven fabric is laid at the bottom of the seedling tray, and the primary moss propagation materials are mixed with peat soil and spread in the tray, and placed in a cool and ventilated place for cultivation; the mass ratio of the primary moss propagation materials to peat soil is 1:3.5 to 4.5, more preferably 1:3.8 to 4.2, and more preferably 1:4. During the culture period, the plant is sprayed with a 38-42% Knop culture medium nutrient mother solution, the spraying frequency is 8-10 days / time, more preferably 9 days / time, pure water is poured once every 3 days to obtain moss with good growth, and the stems are cut and crushed to prepare moss spore powder.

[0048] After obtaining the moss spore powder, the present invention prepares a guest soil spraying agent, wherein the guest soil spraying agent comprises the following components in parts by weight: 3000-3400 parts of planting soil, 2500-2900 parts of water, 2.2-3.9 parts of grass seeds, 2-5 parts of water retaining agent, 10-13 parts of adhesive, 7-11 parts of compound fertilizer, and 200-300 parts of organic fertilizer;

[0049] In the soil-seeding agent, the mass fraction of the planting soil is further preferably 3100 to 3300 parts, and more preferably 3200 parts;

[0050] The mass fraction of the water is further preferably 2600 to 2800 parts, more preferably 2700 parts;

[0051] The mass fraction of the grass seeds is further preferably 2.8 to 3.3 parts, and more preferably 3 parts; the grass seeds include Elymus nutans seeds, Poa annua seeds, and Astragalus obliquus seeds; the mass ratio of the Elymus nutans seeds, Poa annua seeds, and Astragalus obliquus seeds is 0.9 to 1.8:0.6 to 1.2:0.7 to 0.9, and further preferably 1.2 to 1.5:0.8 to 1.0:0.8, and more preferably 1.3:0.9:0.8;

[0052] The mass fraction of the water retaining agent is further preferably 3 to 4 parts, more preferably 3.5 parts; the water retaining agent includes polyacrylamide;

[0053] The mass fraction of the binder is further preferably 11 to 12 parts, more preferably 11.5 parts; the binder comprises pregelatinized corn starch;

[0054] The mass fraction of the compound fertilizer is further preferably 8 to 10 parts, and more preferably 9 parts; diammonium phosphate is designed as a compound fertilizer, and the nitrogen and phosphorus contents meet the standards of "Technical Specifications for Fertilization of Alpine Grasslands" (DB63 / T662-2023).

[0055] The mass fraction of the organic fertilizer is further preferably 220 to 280 parts, more preferably 250 parts, which meets the standards of "Technical Specifications for Fertilization of Alpine Grasslands" (DB63 / T 662-2023).

[0056] The present invention adds diammonium phosphate + organic fertilizer as base fertilizer.

[0057] After obtaining the foreign soil spraying agent, the invention sprays the foreign soil spraying agent on the grassland to be restored. The spraying agent preferably uses a pump or a hydraulic spraying machine to spray the foreign soil spraying agent on the grassland to be restored. The spraying amount of the foreign soil spraying agent is 5721.2-6632.9 g / m 2 , more preferably 6000 to 6300 g / m 2 , more preferably 6200g / m 2 After the soil is sprayed, the non-woven fabric is covered. The non-woven fabric is calculated according to the current "Measurement Method for Carbon Dioxide Release in Evaluation of Biodegradability of Textile Nonwoven Fabrics" (GB / T33616-2017), and its unit area mass is 18-22g / m 2 Degradable non-woven fabrics need special reinforcement when laid in strong wind areas. Within three months of spraying, water the seeds 1 to 2 times a week depending on the soil moisture to ensure seed germination and seedling growth.

[0058] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0059] Example 1

[0060] 1. Collection and processing of imported soil: Select local soil with good fertility, remove large gravel, roots and other debris, pass through a 4mm sieve to remove hard lumps in the soil, and air-dry the soil in a cool place for 48 hours for later use.

[0061] 2. Collection and propagation of moss raw materials: The collection of moss on the Qinghai-Tibet Plateau is in June. Use a hand shovel or a small iron hoe to take a 0.5 cm crust layer and store it in a plastic bag (if not used immediately, it needs to be frozen).

[0062] When processing moss materials, first spread the crust fragments obtained in a ventilated place to dry in the shade for 48 hours, remove the debris, and crush them with a plant crusher for 25 seconds to make the primary generation moss propagation material. Lay non-woven fabric at the bottom of the seedling tray, mix the crushed material with peat soil in a ratio of 1:3.5 and spread them in the tray, place it in a cool and ventilated place, spray it with 38% Knop culture medium nutrient mother solution at 12 days / time, and irrigate it with pure water every 3 days to obtain moss with good growth, and crush the stems after cutting to make moss spore powder.

[0063] 3. Preparation of soil spraying agent: The specific material ratio is prepared according to Table 1, which shows the spraying amount per square meter of the land to be repaired.

[0064] Table 1 Proportion of base material for soil spraying

[0065]

[0066] Example 2

[0067] 1. Collection and processing of imported soil: Select local soil with good fertility, remove large gravel, roots and other debris, pass through a 4mm sieve to remove hard lumps in the soil, and air-dry the soil in a cool place for 48 hours for later use.

[0068] 2. Collection and propagation of moss raw materials: The best time to collect moss on the Qinghai-Tibet Plateau is July, when the temperature and precipitation are suitable for moss growth. It is easier to collect moss on the shady side of the slope of the alpine grassland meadow. Use a hand shovel or a small iron hoe to take a 1.5 cm crust layer and store it in a plastic bag (if not used immediately, it needs to be frozen).

[0069] When processing moss materials, first spread the crust fragments obtained in a ventilated place to dry in the shade for 48 hours, remove the debris, and crush them with a plant crusher for 30 seconds to make the primary generation moss propagation material. Lay non-woven fabric at the bottom of the seedling tray, mix the crushed material with peat soil in a ratio of 1:4 and spread it in the tray, place it in a cool and ventilated place, spray it with 40% Knop culture medium nutrient mother solution at 10 days / time, and irrigate it with pure water every 3 days to obtain well-growing moss, and crush it after cutting the stems to make moss spore powder.

[0070] 3. Preparation of soil spraying agent: The specific material ratio is prepared according to Table 2. Table 2 shows the spraying amount of each spraying base material per square meter of the land to be repaired.

[0071] Table 2 Proportion of base material for soil spraying

[0072]

[0073] Example 3

[0074] 1. Collection and processing of imported soil: Select local soil with good fertility, remove large gravel, roots and other debris, pass through a 4mm sieve to remove hard lumps in the soil, and air-dry the soil in a cool place for 48 hours for later use.

[0075] 2. Collection and propagation of moss raw materials: The best time to collect moss on the Qinghai-Tibet Plateau is August, when the temperature and precipitation are suitable for moss growth. It is easier to collect moss on the shady side of the slope of the alpine grassland meadow. Use a hand shovel or a small iron hoe to take a 2 cm crust layer and store it in a plastic bag (if not used immediately, it needs to be frozen).

[0076] When processing moss materials, first spread the crust fragments obtained in a ventilated place to dry in the shade for 48 hours, remove the debris, and crush them with a plant crusher for 35 seconds to make the primary generation moss propagation material. Lay non-woven fabric at the bottom of the seedling tray, mix the crushed material with peat soil in a ratio of 1:4 and spread it in the tray, place it in a cool and ventilated place, spray it with 42% Knop culture medium nutrient mother solution at 12 days / time, and irrigate it with pure water every 3 days to obtain moss with good growth, and crush the stems after cutting to make moss spore powder.

[0077] 3. Preparation of soil spraying agent: The specific material ratio is prepared according to Table 3, which shows the spraying amount per square meter of the land to be repaired.

[0078] Table 3 Base material ratio in soil spraying agent

[0079]

[0080] Comparative Example 1

[0081] Different from Example 2, no grass seeds, moss spore powder, water retaining agent and binder were added to the soil spraying agent (Group N).

[0082] Comparative Example 2

[0083] Different from Example 2, no Astragalus obliquus, moss spore powder, water retaining agent and binder were added to the guest soil spraying agent (NH group).

[0084] Comparative Example 3

[0085] Different from Example 2, no moss spore powder, water retaining agent and binder were added to the guest soil spraying agent (NM group).

[0086] Comparative Example 4

[0087] Different from Example 2, no Astragalus obliquus seeds, water retaining agent and binder were added to the guest soil spraying agent (NBH group).

[0088] Comparative Example 5

[0089] Different from Example 2, no water retaining agent and binder were added to the soil spraying agent (NBM group)

[0090] Comparative Example 6

[0091] Different from Example 2, no moss crust and Astragalus obliquus seeds were added to the soil spraying agent (NRH group).

[0092] Comparative Example 7

[0093] Different from Example 2, no moss spore powder was added to the soil spraying agent (NRM group).

[0094] Comparative Example 8

[0095] Different from Example 2, no Astragalus stem seeds (NRBH) were added to the soil spraying agent.

[0096] Experimental example

[0097] On June 16, 2024, a high-cold grassland spray restoration experiment was carried out on a grassland slope with a slope of 12 degrees in Gangcha County, Haibei Tibetan Autonomous Prefecture, Qinghai Province (34.292°N, 100.258°E, 3213m above sea level). The grassland slope was divided into 40 plots, each with an area of ​​2m×3m. Ten groups of experiments were set up, namely CK, N, NH, NBH, NBM, NRH, NRM, NRBH, and NRBM groups, with 4 replicates in each group.

[0098] CK indicates control;

[0099] N represents base fertilizer addition and non-woven fabric covering, and the amount of base fertilizer added is the same as in Example 2;

[0100] B represents the addition of moss crust, and the addition amount is the same as in Example 2;

[0101] R represents the addition of soil binder and water retainer, and the types and additives of soil binder and water retainer are the same as those in Example 2;

[0102] H represents single sowing of Gramineae (only Elymus nutans and Poa annua are sown, and the sowing amount is the same as in Example 2);

[0103] M represents mixed sowing (sowing Elymus nutans, Kentucky bluegrass and Astragalus obliquus, the sowing amount is the same as in Example 2), the same below.

[0104] 1. Effects of different spraying schemes on soil properties

[0105] On August 10, 2024, the moisture content and bulk density of the soil at 10 cm of each group were measured. The results are as follows: Figure 1 , Figure 2 shown. Figure 1The results showed that the soil moisture content of the three groups without any addition (N, NH, NM), the mixed sowing group with only binders and water retainers (NRM), and the single sowing group with crust, binders, and water retainers (NBRH) were significantly improved (P < 0.05). Among all the treatments, the soil moisture content of the single sowing group (NH) without any biological crust or binders or water retainers was the highest, reaching 5.62%, followed by the treatment group covered with non-woven fabrics and no reseeding (N), with a moisture content of 5.43%. Except for the treatment groups with only binders and water retainers (NRH and NRM), the moisture content of the single sowing treatment groups of Gramineae was higher than that of the mixed sowing group but not significantly (P > 0.05). Overall, whether it was the addition of crust, binders, water retainers, or mixed additions, the soil moisture content was lower than that of the three groups without the addition of these three materials. However, for the groups with only biocrust addition (NBH, NBM), the simultaneous addition of binder and water retainer (NBRH, NBRM) increased the soil moisture content but not significantly (P>0.05).

[0106] Figure 2 Compared with the control, the soil bulk density of all treatments decreased, but the decrease was not significant (P>0.05). The soil bulk density of the treatment group (NM) without any addition and only mixed sowing was the lowest, reaching 0.773g / cm 3 , compared with the control group (0.861g / cm 3 ) decreased by 10.1%. The group (N) covered with non-woven fabrics without any treatment or reseeding had the smallest decrease in soil bulk density, only 2.9%.

[0107] 2. The impact of different spraying schemes on crust and plants

[0108] Biomass, crust cover and aboveground vegetation cover, plant coverage, total density and density of aboveground vegetation, total plant height and height are important indicators of ecological restoration. They can reflect the degree of vegetation restoration and health status, and thus assess the restoration status of the ecosystem.

[0109] On August 10, 2024, the biomass, crust cover, aboveground vegetation cover, plant coverage, total density and density of aboveground vegetation, total plant height and height of each group were measured and statistically analyzed. The results are as follows: Figures 3 to 10 shown.

[0110] Figure 3The effect of different spraying schemes on the biomass of each group. Compared with the control, the aboveground biomass of all treatments showed a significant increase trend (P < 0.05). The two groups (NH and NM) covered with non-woven fabrics and reseeded had the highest increase. The growth of all treatments from least to most were NRM, N, NBH, NRBM, NRBH, NRH, NBM, NM, and NH. The aboveground biomass of these treatment groups increased by 131.9%, 154.4%, 155.2%, 202.8%, 216.1%, 279.0%, 301.6%, 341.9%, and 356.0%, respectively. Among them, the aboveground biomass of NH was the largest, which was 28.3 g·m -2 Among various spraying treatments, the groups with only crusting (NBH, NBM) or only adding binders and water retainers (NRH, NRM) showed significant differences in aboveground biomass due to the different single and mixed seeding methods (P<0.05); the groups with only non-woven fabric covering without any treatment (NH, NM) and the groups with crusting, binders and water retainers added at the same time (NRBH, NRBM) did not show such differences (P>0.05). Overall, compared with the groups with non-woven fabric covering without any addition (NH, NM), the groups with only adding biological crusting (NBH, NBM) showed significant differences in aboveground biomass (P<0.05). M) would significantly weaken the aboveground biomass of Gramineae after single sowing (P<0.05), and slightly reduce the aboveground biomass after mixed sowing (P>0.05); while the reseeding groups (NRH, NRM) with only water retaining agent and binder added showed the opposite effect, which would significantly weaken the aboveground biomass after mixed sowing (P<0.05), and slightly reduce the aboveground biomass of Gramineae after single sowing (P>0.05); for the treatments with crusting, binder and water retaining agent added at the same time (NRBH, NRBM), although the aboveground biomass was significantly reduced (P<0.05), the decline was relatively mild.

[0111] Figure 4 The effect of different spraying schemes on the crust coverage of each group. After adding crusts to the degraded grassland, the crust coverage of the groups with only crusts (NBH, NBM) increased significantly compared with the control (P<0.05), and the crust coverage of NBH and NBM reached 18.3% and 18.7%, respectively. In the treatment groups (N, NH, NM) without crusts and water retainers and binders, the biological crust coverage of the three groups showed an upward trend compared with the control, but the difference was significant only in the case of reseeding (P<0.05). However, the addition of a single binder and water retainer (NRH, NRM) had no significant effect on the crust coverage (P>0.05). In addition, compared with single seeding, mixed seeding showed a significant improvement only in the combined treatment of crusts, binders, and water retainers (P<0.05), and had no significant effect on the crust coverage under other treatments.

[0112] Figure 5The effect of different spraying schemes on the ground vegetation coverage is shown. In terms of total vegetation coverage, compared with the control group, the vegetation coverage of all treatment groups increased, but the increment of N, NM, NRH, and NRBH groups was not obvious (P>0.05). Among them, the highest vegetation coverage was the single-sowing group NH, which was covered with non-woven fabric without adding spraying materials, with a total coverage of 78%, followed by the mixed-sowing group and the single-sowing group with added biological crusts, with total coverage of 75% and 67%, respectively. The increases of these three groups were 174.6%, 163.2%, and 133.3%, respectively. In terms of the difference in spraying treatment, the incremental effect on the total vegetation coverage was from large to small, respectively, biological crust treatment> mixed treatment (crust, binder, and water retainer were all added, the same below)> binder, water retainer treatment; and in terms of the reseeding method, when spraying materials were added, the total vegetation coverage after mixed sowing was greater than that of single sowing.

[0113] Figure 6 The effects of different spraying schemes on the coverage of aboveground vegetation were analyzed. For the coverage of different grasses, the species richness of grasses was taken into consideration. Therefore, the characteristics of Gramineae and Cyperaceae were mainly counted, and the remaining grasses were classified as weeds (with the same plant density and plant height). As shown in Figure 6, except for the NRH group, the coverage of Gramineae in the other groups was significantly improved compared with the control group (P < 0.05). Among them, the group with the highest Gramineae coverage was NBM, with a coverage of 55%. However, for Cyperaceae plants, the effects of each treatment were different. Some showed a significant growth trend (P < 0.05). For example, in the NRBM group, the number of Cyperaceae plants increased by 54.2% compared with the control group, but some groups showed a significant decrease (P < 0.05). For example, no Cyperaceae plants were found in the NBM group. The coverage of weed plants increased in all treatments, among which NH and NRH showed a significant growth trend (P < 0.05). In terms of treatment results, the addition of crust alone was most conducive to the increase of grass cover. The grass cover of the group covered only with non-woven fabrics and without reseeding was lower than that of the reseeding group under the same treatment, indicating that reseeding can effectively increase the cover of various grass species. However, the treatment of adding only binders and water retaining agents showed different situations in the single-seeding and mixed-seeding groups. The grass and sedge cover of the single-seeding group were significantly lower than those of the mixed-seeding group (P < 0.05), but the increase in the sedge cover was higher than that of the mixed-seeding group.

[0114] Figure 7The effect of different spraying schemes on the density of aboveground vegetation. In terms of total vegetation coverage, compared with the control group, except for the NBM group, the vegetation coverage of all treatment groups increased, among which the increments of NBM, NRH, and NRBH groups were not obvious (P>0.05). Among them, the highest vegetation density was the single-seeding group NH, which was covered with non-woven fabrics without adding spraying materials. The total density of vegetation in the unit sample reached 146 plants, followed by the mixed-seeding group with crusts, binders, and water-retaining agents added, with a total density of 110 plants. The increases of these two groups were 204.2% and 129.2%, respectively. In terms of the difference in spraying treatment, the incremental impact on the total density of vegetation was from large to small, namely, only covering non-woven fabrics> mixed treatment> biological crust treatment> binder and water-retaining agent treatment.

[0115] Figure 8 The effects of different spraying schemes on the density of aboveground vegetation are shown in Figure 2. In terms of grass density, various treatments have the greatest impact on weed density, followed by grasses, but all treatments reduce the density of sedges. For grasses, the two groups with the least obvious treatment effects are NRH and N groups, and the best effect is the mixed single-seeding group NRBM, which increased by 263.6% compared with the control group. In addition, after spraying, except for the NM and NBM groups, the density of grasses is lower than that of weeds. This effect is opposite to that of the control group, indicating that most treatments have a greater increase in the density of weeds than grasses.

[0116] Fig. 9 The effect of different spraying schemes on the height of above-ground vegetation is shown in Figure 2. In terms of total vegetation height (average height), compared with the control group, the plant height of the two groups with only binders and water retainers added and the group with only non-woven fabrics covered without reseeding decreased. The vegetation height of all other treatment groups increased, but only NRBH showed a significant increase (P < 0.05), with an increase of up to 127.9%. The increase in the remaining groups with increased plant height was between 14.6% and 48.9%. Except for the mixed addition treatment group, the plant height of the mixed sowing group was greater than that of the single sowing group in the treatments without addition, only crusting addition, and only binder and water retainer addition, but none of them was significant (P > 0.05).

[0117] Fig.10The effect of different spraying schemes on the height of aboveground vegetation was shown in Figure 1. In terms of grass plant height, the effects of various treatments on the height of Gramineae were uneven. In the N, NRH, NRM, and NRBM groups, the height of Gramineae showed a downward trend. Overall, only the height of Gramineae in the NH group was significantly increased (P < 0.05), with a growth rate of 68.6%. However, the height of Cyperaceae plants increased under all treatments (except for the NBM group, where no Cyperaceae plants were found), and the growth rate in the NM and NRBH groups was significant (P < 0.05). In all treatments, except for the NRBH group, the height of plants in the remaining groups showed Gramineae > Weeds; except for the NBM and NRB groups where no Cyperaceae plants appeared, the height of plants showed Cyperaceae > Weeds; except for the NBM, NRM, and NRBH groups, the height of plants showed Gramineae > Cyperaceae.

[0118] 3. Impact of soil spraying on the ecological environment

[0119] Regarding the measurement methods of soil erosion, the main methods mentioned in the existing technology and national standards are the runoff plot method and the gully measurement method. In terms of the actual situation of the alpine grassland in the northwest, the present invention cannot carry out the development of medium and large ditches or the construction of flow collection pools, which will not only consume a lot of manpower and material resources, but also cause considerable damage to the grassland ecology. Therefore, the surface runoff collection method is used to determine the erosion value. The specific measures are:

[0120] 1. Open a small intercepting channel along the lower edge of the plot after spraying and repair. The width is slightly wider than the edge of the plot, and the length and depth are 10-15cm. After opening, bury the PVC water pipe cut in half and lay plastic cloth inside for collection.

[0121] 2. Insert a thin plastic sheet of equal width along the left and right edges of the plot to prevent horizontal runoff.

[0122] 3. Design the experiment with reference to the local precipitation (the designed water consumption for this experiment is 20L / plot), and use a pesticide sprayer or other sprinkler to sprinkle water evenly and slowly inside the plot to simulate precipitation and produce surface runoff.

[0123] 4. Wait for the surface runoff to stop completely (no sediment or water enters the interception channel), and collect all the washed water and sediment. After the collection is completed, remove all devices, fill the ditch and restore the original landform.

[0124] 5. After the collected sediment is left to stand for one day, the supernatant is removed and the wet sediment at the bottom is placed in an oven and dried at 120° for 12 hours. The completely dried sediment is weighed.

[0125] This method is simple and easy and protects the ecological environment. The data obtained can also better reflect the corrosion control effect of the restoration measures.

[0126] On August 12, 2024, the soil erosion values ​​of the above groups were measured respectively, and the results were as follows: Fig.11 As shown. Compared with the control, the soil erosion values ​​of all treatments decreased, indicating that non-woven fabric covering and various spraying treatments can effectively reduce the surface soil erosion value. Among them, the four groups with added binders and water retaining agents (R) performed particularly well in soil erosion control. NRBM, as the lowest group, had an erosion value of only 3.1g, and the erosion control rate reached 93.5% compared with the control group (47.8g).

[0127] There are multiple indicators for evaluating the effect of ecological restoration, such as vegetation coverage, species diversity, soil carbon sink, soil and water conservation capacity and even economic benefits, so it is rather one-sided to judge the treatment effect by only one indicator. In the present invention, some parameters were measured and the focus was mainly on soil moisture content, aboveground biomass and erosion value. The present invention designs four variables: non-woven fabric, biological crust, water retaining agent (binder), and sowing method. From the results, the effect of non-woven fabric on maintaining soil moisture content is very obvious, which can increase the speed and potential of native vegetation recovery. The addition of biological crust can significantly increase the coverage of the crust after restoration, and the appearance of biological crust can increase soil carbon sink and accelerate the material cycle of grassland, which is very beneficial to the restoration of vegetation and the improvement of soil properties. Judging from the aboveground biomass and sample plot survey results, the aboveground biomass of the comprehensive treatment group to which non-woven fabrics, biological crusts, binders, and water retaining agents were added was less affected by the reseeding method, and the coverage and density of the Gramineae plants in this treatment were both higher. The increase in biomass and coverage in the remaining groups was mainly due to the increase in weed plants (Artemisia, Altai dogwa flower, etc.). From the results of economic benefits and reseeding methods, it can be concluded that the effect achieved by the comprehensive treatment is better than that of a single treatment. In addition, for the reseeding method of the comprehensive treatment, in terms of total vegetation cover and vegetation density, the mixed sowing treatment was significantly better than the single sowing. Finally, in terms of soil erosion values, the performance of the comprehensive treatment was also significantly better than that of other groups. In summary, the best treatment in this experiment was the NRBM group.

[0128] From the above examples, it can be seen that the present invention provides a method for ecological restoration of alpine degraded grasslands. The ecological restoration method of the present invention can quickly form a stable plant community within one growing season, achieve vegetation restoration, carbon fixation and erosion control, and shorten the greening process of the Qinghai-Tibet alpine region.

[0129] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An ecological restoration method for alpine degraded grassland, characterized in that: The steps include: S1. Collect moss crusts on the slopes of alpine grassland meadows; S2. Spread the obtained crust fragments in a ventilated place and dry them in the shade for 45 to 50 hours, then crush them to make the primary generation moss propagation material; S3. The primary moss propagation material is mixed with peat soil, spread flat for cultivation, to obtain moss, and the stems are broken and crushed to make moss spore powder; S4. Mix planting soil, water, mixed grass seeds, moss spore powder, water retaining agent, adhesive, compound fertilizer and organic fertilizer to make a soil spraying agent, and spray it on the grassland slope ≤20°; S5. Cover the soil with non-woven fabric after spraying and water 1 to 2 times a week within three months from spraying.

2. The ecological restoration method according to claim 1, characterized in that: The soil-seeding spraying agent comprises the following components in parts by mass: 3000-3400 parts of planting soil, 2500-2900 parts of water, 2.2-3.9 parts of grass seeds, 2-5 parts of water retaining agent, 10-13 parts of adhesive, 7-11 parts of compound fertilizer and 200-300 parts of organic fertilizer.

3. The ecological restoration method according to claim 2, characterized in that: The grass seeds include Elymus nutans seeds, Poa annua seeds and Astragalus obliquus seeds; the mass ratio of the Elymus nutans seeds, Poa annua seeds and Astragalus obliquus seeds is 0.9-1.8:0.6-1.2:0.7-0.

9.

4. The ecological restoration method according to claim 3, characterized in that: The water retaining agent includes polyacrylamide, and the binder includes starch.

5. The ecological restoration method according to claim 1, characterized in that: The spraying amount of the soil spraying agent is 5721.2-6632.9 g / m 2 .

6. The ecological restoration method according to claim 1, characterized in that: The moss crust layer is collected from June to August on the Qinghai-Tibet Plateau, and the thickness of the moss crust layer is 0.5 to 2 cm.

7. The ecological restoration method according to claim 6, characterized in that: The moss crust layer includes mosses including clump-like true mosses and northern toothed mosses.

8. The ecological restoration method according to claim 7, characterized in that: The mixing mass ratio of the primary moss propagation material to the peat soil is 1:3.5-4.

5. During the cultivation process, the Knop culture medium nutrient mother solution with a concentration of 38-42% is sprayed at a frequency of 8-12 days / time; pure water is poured once every 3 days.

9. The ecological restoration method according to claim 1, characterized in that: The non-woven fabric is a degradable non-woven fabric, and its unit area mass is 18-22 g / m 2 .

Images