A method for repairing alpine degraded grassland

Abstract

This invention discloses a method for restoring degraded alpine grasslands, belonging to the field of ecosystem restoration technology. The method involves preparing bio-sandbags, digging trenches in areas where noxious weeds grow, placing the bio-sandbags in the trenches, spraying the surfaces of the bio-sandbags with biocrust seed, then backfilling the bio-sandbags with soil from the trenches, compacting the soil, and laying sand barriers to restore the alpine degraded grasslands. This method can reduce the competitiveness of noxious weeds, inhibit their growth, and enhance ecosystem diversity without causing pollution or damage to the environment, thereby effectively restoring degraded grasslands in alpine regions with noxious weeds.

Description

Technical Field

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

[0002] Alpine grasslands are experiencing significant degradation due to human interference, overgrazing, and other factors. Activities such as excavation, road construction, and harvesting harm vegetation and exacerbate grassland degradation. Overgrazing affects soil permeability and alters soil properties, further exacerbating grassland degradation. Global warming is also contributing to the degradation of alpine grasslands. Research indicates that increasing grassland degradation is not only severely damaging, declining, and devastating the ecosystem's foundational environment, soil structure, fertility, and soil biota, but is also significantly altering the composition and structure of grassland plant communities.

[0003] Because alpine grassland ecosystems have a poor ability to recover after being damaged, the dominant grass population has shifted to a Kobresia spp. community. This not only disrupts the nutrient supply and demand of the grassland, but also leads to an increase in the number and density of poisonous weeds, a decrease in soil nutrients, and the proliferation of their secretions, further degrading the grassland. These weeds not only encroach on and consume large quantities of high-quality forage grass but also harm the growth and development of grazing livestock. This is especially true in early spring, when the grass is turning green, where livestock poisoning and death from ingesting these weeds are particularly severe. Ingesting these weeds can cause mild poisoning, severe death, and can also reduce fertility rates, miscarriage, and birth defects in females. The economic losses caused by these weeds are estimated to be approximately 2.78 million yuan annually.

[0004] The main control measures for poisonous plants include manual control, chemical control, and biological control methods. However, manual control is time-consuming and labor-intensive, and cannot eradicate the problem of poisonous weeds. Large-scale use of chemical control will pollute the environment, and the reagents used cannot only be effective against poisonous weeds, but will actually harm other normal plants, and cannot kill the large number of poisonous weed seeds stored in the soil. Biological control only uses time-sharing and classified grazing, which is difficult to promote in practical application.

[0005] Therefore, it is necessary to find a restoration method for alpine degraded grasslands to provide a current restoration method for preventing and controlling poisonous weed-type degraded grasslands, so that alpine grasslands can recover quickly, be environmentally friendly, and be easy to promote in the future. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a method for repairing alpine degraded grasslands to solve the problem that there is currently a lack of effective repair methods for alpine degraded grasslands and they are difficult to restore and promote.

[0007] The present invention solves the above technical problems through the following technical means:

[0008] A method for restoring alpine degraded grassland is as follows:

[0009] After October, when most of the poisonous weeds in the alpine grassland have withered, dig trenches along the periphery of the area where the poisonous weeds are concentrated, put bio-sandbags in the trenches, spray the surface of the bio-sandbags with bio-crust seeds, and then backfill the bio-sandbags with the soil from the trenches. Compact the soil and lay sand barriers, which can be grass grids, etc.

[0010] Furthermore, the preparation of the biological crust seed source includes the following raw materials: 10-20 parts by mass of starch and 5-7 parts by mass of spores.

[0011] Furthermore, the preparation steps of the biological crust provenance are as follows: starch is weighed and dispersed in water, spores are added together and mixed and stirred to prepare the biological crust provenance.

[0012] Furthermore, the spores consist of black moss spores and sphagnum moss spores.

[0013] Furthermore, the mass ratio of the black moss spores to the sphagnum moss spores is 3:1.

[0014] Furthermore, the groove is 15-20 cm deep and 30-40 cm wide.

[0015] Furthermore, the biological sandbags include the following raw materials:

[0016] 12-25 parts by mass of AM bacterial agent, 43-55 parts by mass of sucrose powder, 36-40 parts by mass of sainfoin seeds, 10-18 parts by mass of guar gum, 80-122 parts by mass of sodium carboxymethyl cellulose, 170-200 parts by mass of bentonite, 57-68 parts by mass of chitosan, 11-15 parts by mass of glycerol, and 17-23 parts by mass of transglutaminase.

[0017] Furthermore, the preparation steps of the biological sandbag are as follows:

[0018] (1) Sodium carboxymethyl cellulose and chitosan are dissolved in water, glycerol is added, and after mixing, glutamine transaminase is added. After the reaction, the solution is filtered off, and after ripening, a film is blown, and the film is blown into a tube and air-dried;

[0019] (2) Weighing sucrose powder, AM microbial agent, and guar gum and dissolving them in water to obtain a mixed solution, soaking red clover seeds in the mixed solution for 15-30 seconds, taking them out to air-dry, and then adding bentonite to mix to obtain a mixture, filling the tubular membrane obtained in step (1) with the mixture, and sealing it to obtain a biological sandbag.

[0020] Degraded grasslands containing toxic weeds are difficult to control underground, whether through manual or biological control. As they grow and reproduce, toxic weeds produce large amounts of alkaloids and other allelopathic substances that accumulate in the soil, making it difficult for ordinary plants to survive. Therefore, restoration is necessary after October, when nearly all plants in the grassland enter a dormant state. The black moss and peat moss in the bio-sandbags prepared by the present invention take advantage of this period to proliferate. Their roots produce sufficient organic acids, which react with the tubular membranes and residual alkaloids in the soil, creating a favorable environment for the subsequent growth of sainfoin seeds.

[0021] As the weather warms, alpine grasslands experience a resurgence. Excessive surface moisture in the soil is detrimental to plant growth. Water is absorbed through the cellulose membrane into the bentonite, reducing soil moisture. Simultaneously, the bentonite swells, increasing in volume and rupturing the tubular membrane. As the bentonite absorbs moisture, the encased sainfoin seeds begin to germinate and develop roots. The AM microbial agent encasing the seeds forms mycorrhizae, enhancing the sainfoin's competitiveness against toxic weeds. Meanwhile, the tubular membrane, ruptured by the swelling of the bentonite and the action of organic acids from the roots of hydrilla and peat moss during dormancy, exposes the sainfoin, allowing it to quickly seize the habitat of toxic weeds, effectively restoring degraded alpine grasslands infested with toxic weeds.

[0022] Furthermore, in the step (1), after being blown into a tubular shape, the film has a length of 50-60 cm, a width of 15-20 cm, and a thickness of 0.3-0.4 mm.

[0023] Furthermore, the spraying amount of the biological crust seed is 50 mL per square meter of sandbag.

[0024] Beneficial effects:

[0025] (1) The present invention prepares biological sandbags, which can reduce the competitiveness of toxic weeds, inhibit the growth of toxic weeds, and improve the diversity of the ecosystem, thereby achieving the effect of repairing grassland and being environmentally friendly.

[0026] (2) The present invention performs targeted restoration and treatment of degraded grasslands with toxic weeds in high-altitude cold regions, achieving good results and restoring or approximating the original ecological and production functions of the degraded grasslands. DETAILED DESCRIPTION

[0027] The present invention will be described in detail below with reference to the embodiments:

[0028] Example 1: Restoration of alpine degraded grassland

[0029] Preparation of biological crust provenance: Weigh 15 kg of corn starch and disperse it in 30 kg of water, add 4.5 kg of black moss spores and 1.5 kg of peat moss spores and mix and stir to prepare the biological crust provenance.

[0030] Preparation of biological sandbags:

[0031] (1) 101 kg of sodium carboxymethyl cellulose and 63 kg of chitosan were dissolved in 328 kg of water, 13 kg of glycerol was added, and after mixing, 20 kg of transglutaminase was added. After the reaction, the solution was filtered off, and after ripening, the film was blown into a tubular film with a length of 50 cm, a length of 20 cm, and a thickness of 0.3 mm, and air-dried at room temperature;

[0032] (2) Weigh 49 kg of sucrose powder, 18 kg of AM bacterial agent, and 14 kg of guar gum and dissolve them in 81 kg of water to obtain a mixed solution. Soak 38 kg of red clover seeds in the mixed solution for 20 seconds, take them out and air-dry them, and then add them to 185 kg of bentonite and mix them to obtain a mixture. Fill the mixture into the tubular membrane prepared in step (1) and seal it to obtain a biological sandbag. The AM bacterial agents used in the present invention are all commercially available AM ​​composite microorganisms sold by Chenhe Biological Company.

[0033] Restoration of alpine degraded grassland: After most of the poisonous weeds in the alpine grassland have withered in October, dig a 15cm deep and 30cm wide trench along the periphery of the area where the poisonous weeds are concentrated. Place bio-sandbags in the trench and spray the surface of the bio-sandbags with bio-crust seed at a rate of 50mL per square meter of sandbags. Then backfill the bio-sandbags with the soil from the trench, compact the soil and lay grass grids.

[0034] Example 2: Restoration of alpine degraded grassland

[0035] Preparation of biological crust provenance: Weigh 10 kg of corn starch and disperse it in 20 kg of water, add 3.75 kg of black moss spores and 1.25 kg of peat moss spores and mix and stir to prepare the biological crust provenance.

[0036] Preparation of biological sandbags:

[0037] (1) 80 kg of sodium carboxymethyl cellulose and 57 kg of chitosan were dissolved in 274 kg of water, 11 kg of glycerol was added, and after mixing, 17 kg of transglutaminase was added. After the reaction, the solution was filtered off, and after aging, the film was blown into a tubular film with a length of 50 cm, a length of 20 cm, and a thickness of 0.3 mm, and air-dried at room temperature;

[0038] (2) Weigh 43 kg of sucrose powder, 12 kg of AM microbial agent, and 10 kg of guar gum and dissolve them in 65 kg of water to obtain a mixed solution. Soak 36 kg of red clover seeds in the mixed solution for 15 seconds, take them out and air-dry them, and then add them to 170 kg of bentonite and mix them to obtain a mixture. Fill the tubular membrane prepared in step (1) with the mixture and seal it to obtain a biological sandbag.

[0039] Restoration of alpine degraded grassland: After most of the poisonous weeds in the alpine grassland have withered in October, dig a 18cm deep and 35cm wide trench along the periphery of the concentrated growth area of ​​the poisonous weeds, place biological sandbags in the trench, and spray the surface of the biological sandbags with biological crust seed at a spraying rate of 50mL per square meter of sandbags. Then backfill the biological sandbags with the soil from the trench, compact the soil and lay grass grids.

[0040] Example 3: Restoration of alpine degraded grassland

[0041] Preparation of biological crust provenance: Weigh 20 kg of corn starch and disperse it in 40 kg of water, add 5.25 kg of black moss spores and 1.75 kg of peat moss spores and mix and stir to prepare the biological crust provenance.

[0042] Preparation of biological sandbags:

[0043] (1) 122 kg of sodium carboxymethyl cellulose and 68 kg of chitosan were dissolved in 380 kg of water, 15 kg of glycerol was added, and after mixing, 23 kg of transglutaminase was added. After the reaction, the solution was filtered off, and after ripening, the film was blown into a tubular film with a length of 50 cm, a length of 20 cm, and a thickness of 0.3 mm, and air-dried at room temperature;

[0044] (2) Weigh 55 kg of sucrose powder, 25 kg of AM microbial agent, and 18 kg of guar gum and dissolve them in 98 kg of water to obtain a mixed solution. Soak 40 kg of red clover seeds in the mixed solution for 30 seconds, take them out and air-dry them, and then add them to 200 kg of bentonite and mix them to obtain a mixture. Fill the tubular membrane prepared in step (1) with the mixture and seal it to obtain a biological sandbag.

[0045] Restoration of alpine degraded grassland: After October, when most of the poisonous weeds in the alpine grassland have withered, dig a 20cm deep and 32cm wide trench along the periphery of the area where the poisonous weeds are concentrated. Place bio-sandbags in the trench and spray the surface of the bio-sandbags with bio-crust seed at a rate of 50mL per square meter of sandbags. Then backfill the bio-sandbags with the soil from the trench, compact the soil and lay grass grids.

[0046] Comparative Example 1: Restoration of alpine degraded grassland

[0047] The difference between this comparative example and Example 1 is that no biological crust seed was used in the repair of Comparative Example 1. The rest of the repair steps are the same. The repair process is as follows:

[0048] Restoration of alpine degraded grassland: After most of the poisonous weeds in the alpine grassland withered in October, a 15 cm deep and 30 cm wide trench was dug along the periphery of the area where the poisonous weeds were concentrated. The bio-sandbags prepared in Example 1 were placed in the trench. The bio-sandbags were then backfilled with soil from the trench, the soil was compacted, and grass grids were laid.

[0049] Comparative Example 2: Restoration of alpine degraded grassland

[0050] The difference between this comparative example and Example 1 is that no biological sandbags were used during the repair in Comparative Example 2. The rest of the repair steps were the same. The repair process is as follows:

[0051] Restoration of alpine degraded grassland: After most of the poisonous weeds in the alpine grassland withered in October, the biological crust seed prepared in Example 1 was sprayed along the periphery of the area where the poisonous weeds concentrated, with a spraying amount of 50 mL per square meter of grassland, and grass grids were laid.

[0052] Comparative Example 3: Restoration of alpine degraded grassland

[0053] Compared with Example 1, the difference between this comparative example 3 and Example 1 is that no AM bacterial agent is added when preparing the biological sandbags. The remaining steps and raw materials used are the same. The preparation of the biological sandbags is as follows:

[0054] (1): Same as Example 1;

[0055] (2) Weigh 49 kg of sucrose powder and 14 kg of guar gum and dissolve them in 81 kg of water to obtain a mixed solution. Soak 38 kg of red clover seeds in the mixed solution for 20 seconds, take them out and air-dry them. Then, add them to 185 kg of bentonite and mix them to obtain a mixture. Fill the tubular membrane obtained in step (1) with the mixture and seal it to obtain a biological sandbag.

[0056] The biological crust provenance was prepared using Example 1; the restoration of alpine degraded grassland was the same as that in Example 1.

[0057] Comparative Example 4: Restoration of alpine degraded grassland

[0058] Compared with Example 1, the difference between this comparative example 4 and Example 1 is that no bentonite is added when preparing the biological sandbags. Soil from ordinary alpine grassland is used. The remaining steps and raw materials are the same. The preparation process is as follows:

[0059] Preparation of biological sandbags:

[0060] (1): Same as Example 1;

[0061] (2) Weigh 49 kg of sucrose powder, 18 kg of AM microbial agent, and 14 kg of guar gum and dissolve them in 81 kg of water to obtain a mixed solution. Soak 38 kg of red clover seeds in the mixed solution for 20 seconds, take them out and air-dry them. Then, add them to 185 kg of ordinary alpine grassland soil and mix them to obtain a mixture. Fill the tubular membrane prepared in step (1) with the mixture and seal it to obtain a biological sandbag.

[0062] The biological crust provenance was prepared using Example 1; the restoration of alpine degraded grassland was the same as that in Example 1.

[0063] Comparative Example 5: Restoration of alpine degraded grassland

[0064] Compared with Example 1, the difference between this comparative example 5 and Example 1 is that no tubular membrane is prepared when preparing the biological sandbag. The remaining steps and raw materials used are the same. The repair process is as follows:

[0065] Preparation of biological sandbags:

[0066] 49 kg of sucrose powder, 18 kg of AM microbial agent, and 14 kg of guar gum were weighed and dissolved in 81 kg of water to obtain a mixture. 38 kg of sainfoin seeds were soaked in the mixture for 20 seconds, taken out and air-dried, and then added to 185 kg of bentonite and mixed to obtain a mixture. The mixture was filled into ordinary sacks and sealed to prepare biological sandbags.

[0067] The biological crust provenance was prepared using Example 1; the restoration of alpine degraded grassland was the same as that in Example 1.

[0068] Comparative Example 6: Restoration of alpine degraded grassland

[0069] Compared with Example 1, the difference between this comparative example 6 and Example 1 is that the film thickness is 1 mm when preparing the biological sandbag, and the other steps and raw materials used are the same. The repair process is as follows:

[0070] Preparation of biological sandbags:

[0071] (1) 101 kg of sodium carboxymethyl cellulose and 63 kg of chitosan were dissolved in 328 kg of water, 13 kg of glycerol was added, and after mixing, 20 kg of transglutaminase was added. After the reaction, the solution was filtered off, and after ripening, the film was blown into a tubular film with a length of 50 cm, a length of 20 cm, and a thickness of 1 mm, and then air-dried at room temperature;

[0072] Step (2): Same as Example 1.

[0073] The biological crust provenance was prepared using Example 1; the restoration of alpine degraded grassland was the same as that in Example 1.

[0074] Experiment: Restoration of degraded alpine grasslands

[0075] In October 2020, a semi-degraded grassland with a large proportion of poisonous weed coverage was selected as a sample plot in the alpine grassland of Haibei, Qinghai. The poisonous weeds were mainly yellow-flowered oxtera, Gansu oxtera, and drunken horse grass. The sample plot was divided into 7 plots, each with an area of ​​4×4m. A grassland community composition survey experiment was conducted in the plots, and the coverage ratio of poisonous weeds in the plots was counted. The eight plots were repaired according to the repair methods of Example 1 and Comparative Examples 1-6. In mid-August 2021 (the peak season for plant growth), the coverage area of ​​the poisonous weeds after repair, as well as the height and coverage of the red bean grass were measured. The results are shown in Table 1:

[0076] Table 1

[0077]

[0078] From Table 1 we can see that:

[0079] 1. From the total coverage, it can be seen that the total coverage of each sample plot is between 80.4% and 85.3%, indicating moderately degraded grassland. The coverage of noxious weeds in Example 1, Comparative Example 1, Comparative Example 2, Comparative Example 3, Comparative Example 4, Comparative Example 5, and Comparative Example 6 is 20.76%, 19.35%, 22.57%, 18.42%, 21.58%, 23.93%, and 25.81%, respectively. Among them, after restoration in Example 1, the total grassland coverage increased to 98.3%, and the coverage of noxious weeds decreased to 5.64%. In addition, the height of red clover is relatively high, and the coverage reaches 10.27%. It can be seen that Example 1 inhibits the growth of noxious weeds.

[0080] 2. After restoration according to their respective methods, the total grassland coverage of Comparative Example 1 decreased to 77.2%, and the poisonous weed coverage increased to 21.12%. The total grassland coverage of Comparative Example 2 decreased to 70.4%, and the poisonous weed coverage increased to 27.63%. Compared with Example 1, Comparative Example 1 did not prepare biological crust seed sources for auxiliary restoration during the restoration process, and Comparative Example 2 did not prepare biological sandbags. In addition, the total grassland coverage of Comparative Example 6 decreased to 72.1%, and the poisonous weed coverage increased to 28.35%. Since the prepared film in Comparative Example 6 was thicker, the seeds in the sandbags could not break through the sandbags in time to grow outward after germination, and the oxygen space in the bag was limited, which eventually led to the death of red bean grass. It can be seen that the effect of Example 1 is much better than that of Comparative Examples 1, 2, and 6, which proves that when the restoration is carried out by the present invention, the biological crust seed source decomposes the alkaloids produced by the toxic weeds by secreting organic acids, making the soil conducive to the growth of plants other than the toxic weeds. The prepared biological sandbags can further inhibit the growth of toxic weeds, increase the diversity of degraded grasslands, and promote the restoration of degraded grasslands.

[0081] 3. Compared to Example 1, after restoration, the total grassland coverage in Comparative Example 3 increased to 95.2%, while the noxious weed coverage decreased to 8.47%. Furthermore, the sainfoin height reached 60.26 cm, and the coverage reached 8.31%. This is because, during the restoration process in Comparative Example 3, the AM agent was not added to the bio-sandbags during preparation, which failed to effectively infect the sainfoin root system. As the sainfoin grew, this failed to enhance its competitiveness with noxious weeds and prevent them from occupying the habitat. Compared to Example 1, after restoration, the total grassland coverage in Comparative Example 4 increased to 88.5%, while the noxious weed coverage decreased to 13.39%. Furthermore, the sainfoin height reached 66.10 cm, and the coverage reached 5.77%. Due to the lack of bentonite, the soil could not absorb more water. During the slurry return, the surface soil contained excessive moisture, making it unsuitable for plant growth. Furthermore, the tubular membrane could not be squeezed through, preventing the seeds from emerging from the bags and potentially leading to the death of the sainfoin.

[0082] 4. Compared with Example 1, in Comparative Example 5, the total coverage of the grassland after restoration was 91.8%, the coverage of poisonous weeds dropped to 14.57%, and the height of red bean grass was 72.41 cm, and the coverage reached 6.81%. In Comparative Example 5, sacks were used as filling packaging. On the one hand, the degradation rate of sacks was not as fast as the packaging prepared by the present invention, which may cause environmental pollution. On the other hand, before the soil returns to slurry, the bentonite may absorb enough water, and the seeds may germinate in advance, and may die in extreme weather. The biological sandbags in Example 1 have a protective process, which slows down the absorption of water before returning to slurry, plays a protective role, and preserves the red bean grass seeds to germinate and grow in suitable weather.

[0083] The above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit the scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art will appreciate that the technical solutions of the present invention may be modified or replaced with equivalents without departing from the spirit and scope of the technical solutions of the present invention, and such modifications or equivalents shall be encompassed by the claims of the present invention. Any techniques, shapes, and structures not described in detail herein are well known.

Claims

1. A method for restoring alpine degraded grassland, characterized in that: The repair method is as follows: After October, dig trenches along the periphery of the area where noxious weeds are concentrated, place bio-sandbags in the trenches, spray the surface of the bio-sandbags with bio-crust seed, then backfill the bio-sandbags with the soil from the trenches, compact the soil, and lay sand barriers. The biological sandbags include the following raw materials: 12-25 parts by mass of AM bacterial agent, 43-55 parts by mass of sucrose powder, 36-40 parts by mass of sainfoin seeds, 10-18 parts by mass of guar gum, 80-122 parts by mass of sodium carboxymethyl cellulose, 170-200 parts by mass of bentonite, 57-68 parts by mass of chitosan, 11-15 parts by mass of glycerol, and 17-23 parts by mass of transglutaminase: The preparation steps of the biological sandbag are as follows: (1) Sodium carboxymethyl cellulose and chitosan are dissolved in water, glycerol is added, and after mixing, glutamine transaminase is added. After the reaction, the solution is filtered off, and after ripening, a film is blown into a tube and air-dried; (2) Weighing sucrose powder, AM microbial agent, and guar gum and dissolving them in water to obtain a mixed solution, soaking red clover seeds in the mixed solution for 15-30 seconds, taking them out to air-dry, and then adding bentonite to mix to obtain a mixture, filling the tubular membrane obtained in step (1) with the mixture, and sealing it to obtain a biological sandbag.

2. The method for repairing alpine degraded grassland according to claim 1, characterized in that: The preparation of the biological crust seed source includes the following raw materials: 10-20 parts by mass of starch, 5-7 parts by mass of spores.

3. The method for repairing alpine degraded grassland according to claim 2, characterized in that: The steps for preparing the biological crust provenance are as follows: starch is weighed and dispersed in water, and spores are added together and mixed and stirred to prepare the biological crust provenance.

4. The method for restoring alpine degraded grassland according to claim 3, characterized in that: The spores consist of black moss spores and sphagnum moss spores.

5. The method for restoring alpine degraded grassland according to claim 4, characterized in that: The mass ratio of the black moss spores to the sphagnum moss spores is 3:

1.

6. The method for restoring alpine degraded grassland according to claim 1, characterized in that: The trench is 15-20 cm deep and 30-40 cm wide.

7. The method for restoring alpine degraded grassland according to claim 1, characterized in that: In the step (1), after being blown into a tubular shape, the film has a length of 50-60 cm, a width of 15-20 cm, and a thickness of 0.3-0.4 mm.

8. The method for restoring alpine degraded grassland according to claim 1, characterized in that: The spraying amount of the biological crust seed source is 50 mL per square meter of sandbag.

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