Vegetation recovery method for perturbation area of high-altitude permafrost engineering

Abstract

The invention discloses a vegetation recovery method for a perturbation area of a high-altitude permafrost project, which comprises the following steps of: turning soil when a sowing time period is met, reseeding grass seeds, and recovering the perturbation area of the permafrost project. The sowing time period is 3-10 days after the deadline that the daily average ground temperature value is not smaller than a first preset temperature value for continuous 10 days at the depth of 0 cm and the daily average ground temperature value is not smaller than a second preset temperature value for continuous 12 days at the depth of 50-60 cm; covering a plurality of layers of covering nets until the average ground temperature value at the depth of 0 cm for continuous 8 days is not less than a third preset temperature value, removing part of the covering nets, and only retaining one layer of covering net; when the grass seedlings grow to be 5-8 cm high, the last layer of covering net is removed. According to the method, the daily average ground temperature value of the frozen soil disturbance area with the depth of 0 cm and the depth of 50-60 cm is limited, so that endosperm cells in the seeds are kept active after the seeds are sown, the germination rate of the grass seeds is increased, and the vegetation recovery effect is good.

Description

Technical Field

[0001] The present invention relates to the technical field of vegetation restoration, and more specifically, to a method for restoring vegetation in a permafrost engineering disturbance zone at high altitudes. Background Art

[0002] The Qinghai-Tibet Plateau is the main distribution area of ​​high-altitude permafrost, with a permafrost area of ​​1.5 million square kilometers. The Qinghai-Tibet Plateau has a severely cold climate, low average annual temperature, strong seasonal freeze-thaw effects, strong solar radiation, high wind speed, and evaporation far exceeding precipitation. The harsh climate environment has made the plateau's ecological environment extremely fragile.

[0003] The uniqueness, originality and fragility of the high-cold vegetation ecosystem on the plateau pose great challenges to the restoration and maintenance of surface vegetation after disturbance by human activities. Especially after disturbance by construction projects, the surface soil is removed or destroyed, and the soil nutrient content and water holding capacity are greatly reduced. Therefore, vegetation restoration in the plateau permafrost zone is still a difficult problem for ecological environment restoration during construction projects. Summary of the invention

[0004] The present invention provides a method for restoring vegetation in a permafrost engineering disturbance area at high altitude, comprising the following steps: S1. When the frozen soil disturbance area meets the sowing time period, the soil is turned over and the seeds of Elymus nutans are sown again, wherein the sowing time period is 3 to 10 days after the deadline when the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance area for 10 consecutive days is not less than a first preset temperature value and the daily average ground temperature at a depth of 50 to 60 cm in the frozen soil disturbance area for 12 consecutive days is not less than a second preset temperature value; S2, covering multiple layers of covering nets until the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 8 consecutive days is not less than a third preset temperature value, removing part of the covering nets and leaving only one layer of covering nets; S3. When the grass seedlings grow to 5-8 cm in height, remove the last layer of covering net.

[0005] Preferably, the first preset temperature value is 10°C, the second preset temperature is 8°C, and the third preset temperature is 12°C.

[0006] Preferably, the method for calculating the daily average ground temperature value at a depth of 0 cm in the frozen soil disturbance zone specifically comprises the following operations: The ground temperature at 0 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The interval between two consecutive ground temperature measurements was at least 4 hours. The method for calculating the daily average ground temperature at a depth of 50-60 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 50-60 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The interval between two adjacent ground temperature measurements was at least 4 hours.

[0007] Preferably, the method further comprises spreading organic matter on the soil surface of the frozen soil disturbance area after turning the soil and before sowing grass seeds, wherein the organic matter comprises at least peat or sawdust.

[0008] Preferably, the sowing rate of the grass seeds is 1-2.5 kg / mu.

[0009] Preferably, the method further comprises applying nitrogen fertilizer after reseeding the grass seeds, wherein the amount of nitrogen fertilizer applied per mu is 2 to 3 times the sowing amount of the grass seeds.

[0010] Preferably, the covering net is a dense green net, and the mesh size of the covering net includes any one or more of 800 mesh, 1000 mesh, 1500 mesh, and 2000 mesh; Wherein, when the sowing amount of the grass seeds is less than or equal to 2 kg / mu, the mesh size of the covering net is 1500 mesh or 2000 mesh; When the sowing amount of the grass seeds is greater than 2 kg / mu, the mesh size of the covering net is 800 mesh or 1000 mesh.

[0011] The present invention has at least the following beneficial effects: First, the present invention limits the daily average ground temperature value at a depth of 0 cm in the frozen soil disturbance zone for 10 consecutive days and the daily average ground temperature value at a depth of 50-60 cm in the frozen soil disturbance zone for 12 consecutive days, so that the soil in the frozen soil disturbance zone can maintain a suitable temperature, which helps to keep the endosperm cells inside the seeds active, and helps cell division and cell growth inside the seeds, avoiding the problem of low temperature and large temperature difference between day and night in high altitude areas affecting the development of seed embryos, helping to increase the germination rate of grass seeds, and the germinated seeds can better absorb nutrients in the soil in the frozen soil disturbance zone and grow.

[0012] Second, the present invention limits the daily average ground temperature value at a depth of 0 cm in the frozen soil disturbance zone for 8 consecutive days and the third preset temperature value, thereby ensuring that the upper dense green net is removed in time after the embryo grows out of the seed, and a layer of dense green net is retained, which is conducive to the growth of seedlings toward the soil surface, the expansion of leaves for photosynthesis, and the rapid recovery of vegetation in high-altitude permafrost engineering disturbance areas.

[0013] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A photograph of soil turning operation according to one of the technical solutions of the present invention; Figure 2 A photo of a covering net for covering one of the technical solutions of the present invention Figure 3 This is a photo taken 30 days after sowing of Example 1 of one of the technical solutions of the present invention. DETAILED DESCRIPTION

[0015] The present invention is further described in detail below in conjunction with embodiments so that those skilled in the art can implement the invention with reference to the description.

[0016] It should be noted that the experimental methods described in the following embodiments are conventional methods unless otherwise specified, and the reagents and materials can be obtained from commercial channels unless otherwise specified.

[0017] The permafrost disturbance area is located in the hinterland of the Qinghai-Tibet Plateau, on the right bank of the Tuotuo River on the first-level terrace. It is controlled by the high-altitude westerly wind belt, with a dry and cold climate, more wind and less rain, changeable weather, and low temperatures all year round. The permafrost disturbance area has a wide and flat terrain, with mounds, swamps, streams, and shoals of water occasionally distributed. In its natural state, the surface vegetation is alpine mosses and lichens. The overall vegetation coverage rate is 10~40%, and the vegetation is sparse.

[0018] The freezing time of the frozen soil disturbance zone is generally from about October of each year to about May of the following year. Based on the freezing and daily average ground temperature values ​​of the frozen soil disturbance zone for many years, the present invention starts to record the starting freezing time, melting time and corresponding daily average ground temperature values ​​of the frozen soil disturbance zone in 2022, and completes the following embodiments and comparative examples in 2023. Among them, the starting freezing time, melting time and daily average ground temperature values ​​of important nodes recorded since 2022 are as follows: The initial freezing time at a depth of 0 cm in the permafrost disturbance zone is October 20, 2022, the initial melting time is April 1, 2023, and the complete melting time is April 4, 2023. The freezing period lasts for 164 days. The initial freezing time at a depth of 50 cm in the permafrost disturbance zone is October 30, 2022, the initial melting time is April 4, 2022, and the complete melting time is April 7, 2023. The freezing period lasts for 157 days. The deadline for the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 10 consecutive days to be no less than the first preset temperature value and the daily average ground temperature at a depth of 50-60 cm in the frozen soil disturbance zone for 12 consecutive days to be no less than the second preset temperature value is July 7, 2023. The starting time for the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 8 consecutive days to be greater than or equal to the third preset temperature (12°C) is July 16, 2023.

[0019] Because of its good cold resistance, Elymus nutans can survive in low temperature environments, withstand the cold climate conditions of the plateau, and adapt to the environment of strong ultraviolet radiation and large temperature difference between day and night on the plateau. At the same time, it has good salt and alkali resistance and can absorb enough nutrients and water from the soil environment of the plateau to maintain its own growth. Elymus nutans has a well-developed root system, which can hold the soil tightly during its growth and reduce soil erosion, which is very important for the stability and recovery of the ecosystem in the plateau.

[0020] The reseeding areas in the following embodiments and comparative examples are all located in the frozen soil disturbance area. Except for the different vegetation restoration methods, the other conditions of the reseeding areas are the same.

[0021] <Example 1> The method for restoring vegetation in high-altitude permafrost engineering disturbance areas includes the following steps: S1. After the frozen soil disturbance zone at a depth of 0 to 50 cm has completely melted, when the sowing period is met, the soil is turned over, peat debris is spread on the soil surface of the frozen soil disturbance zone, and on July 10, 2023, Elymus nutans seeds are sown at a sowing rate of 1 kg / mu, and nitrogen fertilizers including urea are applied at an application rate of 2 kg / mu, wherein the sowing period is 3 days after the deadline when the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 10 consecutive days is not less than the first preset temperature value (10°C) and the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone for 12 consecutive days is not less than the second preset temperature value (8°C); S2, covering with double-layer covering nets until the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 8 consecutive days is not less than the third preset temperature value (12°C) (July 16, 2023), removing part of the covering nets and leaving only one layer of covering nets, the covering net is a dense green net, and the mesh size of the covering net is 1500 meshes; S3. When the grass seedlings grow to 5 cm in height, remove the last layer of covering net.

[0022] The method for calculating the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 0 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 hours. The method for calculating the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 50 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 h.

[0023] <Example 2> The method for restoring vegetation in high-altitude permafrost engineering disturbance areas includes the following steps: S1. After the frozen soil disturbance zone at a depth of 0 to 50 cm has completely melted, when the sowing period is met, the soil is turned over, peat debris is spread on the soil surface of the frozen soil disturbance zone, and on July 13, 2023, 2 kg / mu of Elymus nutans seeds are sown, and nitrogen fertilizers including urea are applied at an application rate of 6 kg / mu, wherein the sowing period is 6 days after the deadline when the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 10 consecutive days is not less than the first preset temperature value (10°C) and the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone for 12 consecutive days is not less than the second preset temperature value (8°C); S2, covering with double-layer covering nets until the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 8 consecutive days is not less than the third preset temperature value (12°C) (July 16, 2023), removing part of the covering nets and leaving only one layer of covering nets, the covering nets being a dense green net with a mesh size of 2000; S3. When the grass seedlings grow to 5 cm in height, remove the last layer of covering net.

[0024] The method for calculating the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 0 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 hours. The method for calculating the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 50 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 h.

[0025] <Example 3> The method for restoring vegetation in high-altitude permafrost engineering disturbance areas includes the following steps: S1. After the frozen soil disturbance zone at a depth of 0 to 50 cm has completely melted, when the sowing period is met, the soil is turned over, peat debris is spread on the soil surface of the frozen soil disturbance zone, and on July 16, 2023, 2.5 kg / mu of Elymus nutans seeds are sown, and nitrogen fertilizers including urea are applied at an application rate of 5 kg / mu, wherein the sowing period is 9 days after the deadline when the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 10 consecutive days is not less than the first preset temperature value (10°C) and the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone for 12 consecutive days is not less than the second preset temperature value (8°C); S2, covering with double-layer covering nets until the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 8 consecutive days is not less than the third preset temperature value (12°C) (July 16, 2023), removing part of the covering nets and leaving only one layer of covering nets, the covering nets being a dense green net with a mesh size of 800 meshes; S3. When the grass seedlings grow to 8 cm in height, remove the last layer of covering net.

[0026] The method for calculating the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 0 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 hours. The method for calculating the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 50 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 h.

[0027] <Control group> In response to the patchy bare land (the surface of the frozen soil engineering disturbance area is distributed in discontinuous patches, with dense vegetation inside the patches and bare land without vegetation around it), on May 25, 2023, the surface soil was loosened with a spike harrow, and organic matter including peat debris and sawdust was spread on the surface, and then seeds of Elymus nutans were sown at a sowing rate of 2 kg / mu.

[0028] <Comparative Example 1> The method for restoring vegetation in high-altitude permafrost engineering disturbance areas includes the following steps: S1. After the frozen soil disturbance zone at a depth of 0 to 50 cm has completely melted, the soil is turned over, peat debris is spread on the soil surface of the frozen soil disturbance zone, and on July 4, 2023 (3 days before the deadline of the sowing period), 2.5 kg / mu of Elymus nutans seeds are sown, and nitrogen fertilizers including urea are applied at an application rate of 5 kg / mu, wherein the sowing period is 3 to 10 days after the deadline when the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 10 consecutive days is not less than the first preset temperature value (10°C) and the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone for 12 consecutive days is not less than the second preset temperature value (8°C); S2, covering with double-layer covering nets until the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 8 consecutive days is not less than the third preset temperature value (12°C) (July 16, 2023), removing part of the covering nets and leaving only one layer of covering nets, the covering nets being a dense green net with a mesh size of 800 meshes; S3. When the grass seedlings grow to 8 cm in height, remove the last layer of covering net.

[0029] The method for calculating the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 0 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 hours. The method for calculating the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 50 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 h.

[0030] <Comparative Example 2> The method for restoring vegetation in high-altitude permafrost engineering disturbance areas includes the following steps: S1. After the frozen soil disturbance zone at a depth of 0 to 50 cm has completely melted, the soil is turned over, peat debris is spread on the soil surface of the frozen soil disturbance zone, and on July 7, 2023 (the deadline of the sowing period), 2.5 kg / mu of Elymus nutans seeds are sown, and nitrogen fertilizers including urea are applied at an application rate of 5 kg / mu, wherein the sowing period is 3 to 10 days after the deadline that the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 10 consecutive days is not less than the first preset temperature value (10°C) and the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone for 12 consecutive days is not less than the second preset temperature value (8°C); S2, covering with double-layer covering nets until the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 8 consecutive days is not less than the third preset temperature value (12°C) (July 16, 2023), removing part of the covering nets and leaving only one layer of covering nets, the covering nets being a dense green net with a mesh size of 800 meshes; S3. When the grass seedlings grow to 8 cm in height, remove the last layer of covering net.

[0031] The method for calculating the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 0 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 hours. The method for calculating the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 50 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 h.

[0032] <Comparative Example 3> The method for restoring vegetation in high-altitude permafrost engineering disturbance areas includes the following steps: S1. After the frozen soil disturbance zone at a depth of 0 to 50 cm has completely melted, when the sowing period is met, the soil is turned over, peat debris is spread on the soil surface of the frozen soil disturbance zone, and on July 13, 2023, 2 kg / mu of Elymus nutans seeds are sown, and nitrogen fertilizers including urea are applied at an application rate of 6 kg / mu, wherein the sowing period is 6 days after the deadline when the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 10 consecutive days is not less than the first preset temperature value (10°C) and the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone for 12 consecutive days is not less than the second preset temperature value (8°C); S2. When the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone is not less than the third preset temperature value (12°C) for 8 consecutive days (July 16, 2023), a layer of covering net is covered, wherein the covering net is a dense green net with a mesh size of 2000; S3. When the grass seedlings grow to 5 cm in height, remove the covering net.

[0033] The method for calculating the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 0 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 hours. The method for calculating the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 50 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 h.

[0034] <Comparative Example 4> The method for restoring vegetation in high-altitude permafrost engineering disturbance areas includes the following steps: S1. After the frozen soil disturbance zone at a depth of 0 to 50 cm has completely melted, when the sowing period is met, the soil is turned over, peat debris is spread on the soil surface of the frozen soil disturbance zone, and on July 13, 2023, 2 kg / mu of Elymus nutans seeds are sown, and nitrogen fertilizers including urea are applied at an application rate of 6 kg / mu, wherein the sowing period is 6 days after the deadline when the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 10 consecutive days is not less than the first preset temperature value (10°C) and the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone for 12 consecutive days is not less than the second preset temperature value (8°C); S2, covering with a double layer of covering nets until the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 8 consecutive days is not less than the third preset temperature value (12°C) (July 16, 2023), removing part of the covering nets and leaving only one layer of covering nets, the covering net is a dense green net, and the mesh size of the covering net is 1000 mesh; S3. When the grass seedlings grow to 5 cm in height, remove the last layer of covering net.

[0035] The method for calculating the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 0 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 hours. The method for calculating the daily average ground temperature at a depth of 50 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 50 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The time interval between two adjacent ground temperature measurements was 4 h.

[0036] <Vegetation restoration results> The germination rates of Examples 1 to 3, the control group and Comparative Examples 1 to 4 15 days after sowing and the average grass seedling growth heights 30 days after sowing were statistically analyzed. The sowing results of Elymus nutans seeds are shown in Table 1 below: Table 1 Germination rate of each group 15 days after sowing and average grass seedling height 30 days after sowing Germination rate (%) Average grass seedling growth height (cm) Example 1 89.4 9.5 Example 2 94.2 9.4 Example 3 91.5 9.3 Control group 37.2 6.1 Comparative Example 1 62.3 6.7 Comparative Example 2 77.6 8.3 Comparative Example 3 84.7 8.1 Comparative Example 4 83.4 8.3 According to the data in Table 1, the methods of Examples 1 to 3 significantly improve the germination rate of grass seeds in the frozen soil disturbance area, the growth height of grass seedlings is also significantly improved, and the vegetation restoration effect is better. The reasons are analyzed by the daily average ground temperature of the frozen soil disturbance area at a depth of 0 cm for 8 consecutive days and the frozen soil disturbance area at a depth of 50 cm for 10 consecutive days can keep the soil in the permafrost disturbance zone at a suitable temperature, help keep the endosperm cells inside the seeds active, help cell division and cell growth inside the seeds, avoid the problem that the temperature in high-altitude areas is low and the temperature difference between day and night affects the development of seed embryos, help increase the germination rate of grass seeds, and the germinated seeds can better absorb nutrients in the soil in the permafrost disturbance zone and grow; using the method of Example 2, compared with Comparative Example 3, the germination rate of grass seeds in the permafrost disturbance zone is significantly improved, and the growth height of grass seedlings is also significantly improved, indicating that the double-layer dense green net can cover and maintain the sowing area, increase the temperature of the soil, and help seed germination, while the permafrost disturbance zone is 0 cm The limitation of the daily average ground temperature value for 8 consecutive days and the third preset temperature value can ensure that the upper dense green net is removed in time after the embryo grows out of the seed, and a layer of dense green net is retained, which is conducive to the growth of seedlings to the soil surface and the unfolding of leaves for photosynthesis, and is conducive to the rapid recovery of vegetation in high-altitude permafrost engineering disturbance areas; Compared with Example 4, the grass seed germination rate and the growth height of grass seedlings in the permafrost disturbance area in Example 2 are significantly improved, indicating that the covering net with a mesh number matching the grass seed sowing amount can effectively improve the grass seed germination rate and the growth height of grass seedlings.

[0037] During the experiment, it was found that the frozen soil disturbance area was re-sown with Elymus nutans seeds during the sowing period, and the dense green net was not covered during the germination and seedling growth process. The statistical data showed that the average growth height of the grass seedlings 30 days after re-sowing was less than 6.3 cm, which was significantly lower than that of Examples 1 to 3. The reason was analyzed and it was found that the dense green net could not only effectively reduce the damage to the grass seedlings caused by weather phenomena such as hail, but also reduce the wind speed and increase the temperature, which had an obvious effect on the rapid generation of grass seedlings in the short summer on the plateau.

[0038] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the embodiments shown and described herein.

Claims

1. A method for restoring vegetation in high-altitude permafrost engineering disturbance areas, characterized in that: The following steps are involved: S1. When the frozen soil disturbance area meets the sowing time period, the soil is turned over and the seeds of Elymus nutans are sown again, wherein the sowing time period is 3 to 10 days after the deadline when the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance area for 10 consecutive days is not less than a first preset temperature value and the daily average ground temperature at a depth of 50 to 60 cm in the frozen soil disturbance area for 12 consecutive days is not less than a second preset temperature value; S2, covering multiple layers of covering nets until the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone for 8 consecutive days is not less than a third preset temperature value, removing part of the covering nets and leaving only one layer of covering nets; S3. When the grass seedlings grow to 5-8 cm in height, remove the last layer of covering net.

2. The method for restoring vegetation in a permafrost engineering disturbance area at high altitude according to claim 1, characterized in that: The first preset temperature value is 10°C, the second preset temperature is 8°C, and the third preset temperature is 12°C.

3. The method for restoring vegetation in a permafrost engineering disturbance area at high altitude according to claim 1, characterized in that: The method for calculating the daily average ground temperature at a depth of 0 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 0 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The interval between two consecutive ground temperature measurements was at least 4 hours. The method for calculating the daily average ground temperature at a depth of 50-60 cm in the frozen soil disturbance zone specifically includes the following operations: The ground temperature at 50-60 cm in the permafrost disturbance zone was measured several times a day and the average value was taken. The interval between two adjacent ground temperature measurements was at least 4 hours.

4. The method for restoring vegetation in a permafrost engineering disturbance area at high altitude according to claim 1, characterized in that: The method also includes spreading organic matter on the soil surface of the frozen soil disturbance area after turning the soil and before sowing grass seeds, wherein the organic matter includes at least peat or sawdust.

5. The method for restoring vegetation in a permafrost engineering disturbance area at high altitude according to claim 1, characterized in that: The sowing rate of the grass seeds is 1-2.5 kg / mu.

6. The method for restoring vegetation in a permafrost engineering disturbance area at high altitude according to claim 5, characterized in that: It also includes applying nitrogen fertilizer after reseeding grass seeds, with the amount of nitrogen fertilizer applied per mu being 2 to 3 times the amount of grass seeds sown.

7. The method for restoring vegetation in a permafrost engineering disturbance area at high altitude according to claim 6, characterized in that: The covering net is a dense green net, and the mesh size of the covering net includes any one or more of 800 mesh, 1000 mesh, 1500 mesh, and 2000 mesh; Wherein, when the sowing amount of the grass seeds is less than or equal to 2 kg / mu, the mesh size of the covering net is 1500 mesh or 2000 mesh; When the sowing amount of the grass seeds is greater than 2 kg / mu, the mesh size of the covering net is 800 mesh or 1000 mesh.

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