Ecological restoration method for alpine mine

Abstract

The invention relates to an ecological restoration method for a high and cold mine, and belongs to the technical field of ecological restoration. The ecological restoration method for the high-cold mine comprises the step of performing ecological restoration on the high-cold mine by adopting vegetation configuration of shrubs, herbaceous plants A and herbaceous plants B, the herbaceous plants A comprise at least four of elymus dahuricus, siberian wildrye herb, festuca arundinacea, bluegrass, stipa purpurea, ryegrass, frozen artemisia stelleriana and herba artemisiae annuae; the herbaceous plant B comprises at least three of artemisia desertorum, plantain herb, alfalfa, astragalus membranaceus, dandelion and oxytropis philippinarum; the shrub species comprise at least two of sophora moorcroftiana, sabina vulgaris, sea-buckthorn, caragana and buddleia. According to the method, specific vegetation configuration of shrubs, herbaceous plants A and herbaceous plants B is adopted, and soil microorganism resources are recovered quickly; the extreme environment of high and cold mines can be overcome; the ecological system is quickly and efficiently restored, only one-time sowing is needed, and the cost is low; the vegetation and microorganisms interact with each other, so that the survival rate of the vegetation is high.

Description

Technical Field

[0001] The invention relates to an ecological restoration method for a high-cold mine, belonging to the technical field of ecological restoration. Background Art

[0002] Alpine mines have unique environmental conditions, including extreme cold, drought, poor soil nutrients, and low soil microbial diversity and richness. Under natural conditions, it usually takes a long time for the ecosystem function of abandoned alpine mines to recover, much longer than that of ordinary abandoned mines. Therefore, ecological restoration of abandoned alpine mines and restoration of their ecosystem functions have become key issues that need to be urgently addressed.

[0003] Under the extreme environmental conditions of alpine mines, microorganisms show unique adaptability and functional diversity, which is crucial to maintaining the stability of alpine ecosystems. The maintenance of soil multifunctionality and the regulation of biogeochemical cycles in alpine areas depend on microorganisms, which play a core role in primary production, carbon fixation and total nitrogen mineralization. For example, some cold-resistant microorganisms can decompose organic matter in low-temperature environments, convert complex organic carbon into simple inorganic carbon, and participate in the carbon cycle of soil; at the same time, they can also convert atmospheric nitrogen into a nitrogen source available to plants through biological nitrogen fixation, increase the nitrogen content of the soil, and promote plant growth. In addition, soil microorganisms also promote the material cycle and energy flow of the ecosystem by mineralizing organic matter, degrading organic waste, fixing nitrogen in the atmosphere, dissolving phosphorus minerals, and providing nutrients to plants, thereby supporting the functional recovery of the ecosystem. For example, some microorganisms can secrete organic acids, dissolve phosphorus minerals in the soil, release phosphorus, increase the availability of phosphorus in the soil, meet the phosphorus demand of plant growth, promote the development of plant roots and the growth of aboveground parts, and thus improve the coverage of vegetation and the stability of the ecosystem.

[0004] Alpine mines have extremely special environmental conditions, including extreme cold, drought, and poor soil nutrients, which lead to serious damage to soil microbial resources and a significant decrease in microbial diversity, thus affecting the normal function recovery of the ecosystem. The traditional mine ecological restoration model has the following problems:

[0005] 1. The ecological function of vegetation is poor and single

[0006] In the traditional ecological restoration model, the selected vegetation types are relatively single, and most of them are herbaceous plants. These plants are extremely difficult to grow in high-altitude mines and are difficult to adapt to harsh environmental conditions, resulting in poor ecological restoration effects. For example, in the high-altitude mining environment, single herbaceous plants have shallow roots and are difficult to take root in poor and compact soil. They are prone to withering and dying in strong winds and low temperatures. They cannot effectively cover the surface and prevent soil erosion, nor can they provide sufficient habitat and reproduction space for other organisms. It is difficult to establish the food chain and nutrient cycle of the ecosystem.

[0007] 2. Failure to consider the restoration of soil microbial resources

[0008] Existing technologies focus more on the planting and covering of vegetation, while ignoring the restoration of soil microbial communities. However, the role of soil microorganisms in mine ecological restoration cannot be ignored. They are key factors in maintaining the material cycle of the ecosystem, promoting plant growth and improving soil fertility. In abandoned alpine mines, due to long-term mining activities and harsh environmental conditions, the structure of the soil microbial community has been severely damaged, the number of beneficial microorganisms has been greatly reduced, and the self-purification ability and nutrient recycling capacity of the soil have decreased. For example, the number of some microorganisms that can decompose organic matter and release nutrients has decreased, resulting in insufficient accumulation of organic matter in the soil, making it difficult to improve soil fertility, affecting plant growth and the recovery rate of the ecosystem.

[0009] 3. Lack of comprehensive restoration design of plants and microorganisms

[0010] Traditional restoration models do not fully consider the interaction between plant species and soil microorganisms, especially the combination of native plants and shrubs, and fail to effectively improve vegetation coverage and soil microbial diversity, resulting in limited restoration effects and slow ecosystem recovery. For example, a single vegetation planting model cannot provide a rich source of organic matter and a diverse living environment for soil microorganisms, while the uniformity of soil microorganisms cannot meet the needs of different plants for nutrients and microenvironments. The mutual promotion between the two cannot be fully exerted, and the stability and self-sustaining ability of the ecosystem are weak.

[0011] CN113723808A discloses a plant configuration method and application for ecological restoration of open pit closed coal mines in alpine areas. In the first year, pioneer herbs are sown. The herb species selection basis is the distribution of herb species in the undisturbed area adjacent to the edge of the mining area after stopping mining activities for one year, and its importance value>0.05, niche width>1, and the niche overlap value with other species is not 0, so as to preliminarily improve the site conditions of the plants; in the second year, shrubs and herbs are planted, and species with an important value>0.03, niche width>1, and a niche overlap value with other species in the same area as the first year are selected as the first replanting herb for replanting; from the third to the fifth year, trees are planted, and species with an important value>0.03, niche width>1, and a niche overlap value with other species in the undisturbed area are selected as the second replanting herb for replanting, so as to accelerate the succession of the ecosystem. However, it requires many years of operation, high labor cost, low efficiency, low survival rate of trees, and high cost. Summary of the invention

[0012] The purpose of the invention is to provide a method for ecological restoration of alpine mines.

[0013] To achieve the purpose of the present invention, the alpine mine ecological restoration method of the present invention comprises:

[0014] A vegetation configuration of shrubs + herbaceous plants A + herbaceous plants B is used to carry out ecological restoration of alpine mines; the herbaceous plants A include at least four of Elymus dahliae, Elymus sibiricus, tall fescue, Poa annua, Stipa purpurogena, Lolium perenne, Artemisia tundraensis, and Kobresia sibiricum; the herbaceous plants B include at least three of Artemisia ordosica, Plantain, Alfalfa, Astragalus obliquus, Taraxacum sinensis, and Oxytropis purpurogenum; the shrub species include at least two of Sophora japonica, Juniperus chinensis, Hippophae rhamnoides, Caragana, and Buddaria japonica.

[0015] The following are the Latin names of the plants mentioned above:

[0016] Elymus dahuricus Turcz.

[0017] Elymus sibiricus L.

[0018] Tall fescue: Festuca elata Keng ex EBAlexeev.

[0019] Poa annua L.

[0020] Purple Stipa: Stipapurpurea Griseb.

[0021] Ryegrass: Lolium perenne L.

[0022] Tundra Artemisia: Artemisia stracheyi Hook.f.&Thomson ex CBClarke.

[0023] Kobresia pygmaea (CBClarke) CBClarke.

[0024] Artemisia desertorum Spreng.

[0025] Plantain: Plantago depressa Willd.

[0026] Alfalfa: Medicago sativa L.

[0027] Astragalus laxmannii Jacq.

[0028] Dandelion: Taraxacum sinicum Kitag.

[0029] Oxytropis coerulea (Pall.) DC.

[0030] Sophora moorcroftiana Kanitz.

[0031] Sandy juniper: Juniperus sabina L.

[0032] Sea buckthorn: Hippophae rhamnoides L.

[0033] Caragana: Caragana sinica (Buc'hoz) Rehder.

[0034] Buddleja lindleyana Fortune.

[0035] In a specific embodiment, the altitude of the alpine mine is 3500-4100 meters.

[0036] In a specific embodiment, the sowing seed density of the herbaceous plant A + herbaceous plant B is 20-30 g / m 2 .

[0037] In a specific embodiment, the sowing seed density of each plant of the herbaceous plant A is 3 to 9 g / m 2 .

[0038] In a specific embodiment, the sowing seed density of each plant of the herbaceous plant B is 0.05-2 g / m 2 .

[0039] In a specific embodiment, the shrub species include 2 to 4 species of Sophora japonica, Juniperus chinensis, Hippophae rhamnoides, Caragana spp., and Buddleija truncatula; and the herbaceous plant B preferably includes three species of Medicago truncatula, Astragalus obliquus, and Oxytropis purpurogena.

[0040] In a specific embodiment, the method comprises sowing shrubs + herbaceous plants A + herbaceous plants B at one time.

[0041] In a specific implementation manner, the planting spacing of the shrubs is 1.5m to 2.5m.

[0042] In a specific embodiment, the shrub seedlings are 1 to 3 meters long rooted seedlings, and the top 1 / 3 to 2 / 3 of the stems and leaves are subtracted when the shrubs are planted.

[0043] To further increase the survival rate of shrubs, it is preferred to plant shrubs in clusters, with 3 to 6 shrubs planted in each nest.

[0044] Beneficial effects: The present invention comprehensively considers the restoration of soil microbial resources and integrates the comprehensive restoration of plants and microorganisms, which can effectively improve the vegetation coverage and the diversity of soil microorganisms, quickly and efficiently restore the ecosystem at a low cost, which is specifically manifested in:

[0045] 1. The present invention adopts a specific "vegetation configuration of shrubs + herb A + herb B", which quickly restores soil microbial resources, improves soil nutrients and microbial activity, and enhances the stability of soil structure.

[0046] 2. The present invention adopts a specific "vegetation configuration of shrubs + herbaceous plants A + herbaceous plants B" to overcome the extreme environment of high-cold mines. Under extreme environmental conditions, it can provide strong adaptability and has a high promotion value.

[0047] 3. The present invention adopts a specific "vegetation configuration of shrubs + herb A + herb B" to utilize the "fertilizer island" effect and soil microbial resources to quickly and efficiently repair the ecosystem, providing a self-sustaining support system for the entire ecosystem, which can not only enhance the growth ability of vegetation, but also improve the stability and sustainability of the entire ecosystem. Only one sowing is required, and the cost is low. Over time, the restoration area will gradually form a stable ecosystem that can self-regulate and maintain. Through ecological restoration, the vegetation coverage of the restoration area will be greatly improved, which can effectively prevent problems such as soil erosion and desertification, and improve the environmental quality of the mining area.

[0048] 4. The method of the present invention can effectively improve the adaptability of vegetation growth, enhance vegetation coverage, and promote interaction between vegetation and microorganisms, thereby increasing the survival rate of vegetation. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is a schematic diagram of the plant configuration for ecological restoration of alpine mines according to the present invention.

[0050] 1- shrub planting; 2- mixed grass seed spraying layer; 3- slope type high-cold mine; 4- platform type high-cold mine. DETAILED DESCRIPTION

[0051] To achieve the purpose of the present invention, the alpine mine ecological restoration method of the present invention comprises:

[0052] A vegetation configuration of shrubs + herbaceous plants A + herbaceous plants B is used to carry out ecological restoration of alpine mines; the herbaceous plants A include at least four of Elymus dahliae, Elymus sibiricus, tall fescue, Poa annua, Stipa purpurogena, Lolium perenne, Artemisia tundraensis, and Kobresia sibiricum; the herbaceous plants B include at least three of Artemisia ordosica, Plantain, Alfalfa, Astragalus obliquus, Taraxacum sinensis, and Oxytropis purpurogenum; the shrub species include at least two of Sophora japonica, Juniperus chinensis, Hippophae rhamnoides, Caragana, and Buddaria japonica.

[0053] In a specific embodiment, the altitude of the alpine mine is 3500-4100 meters.

[0054] In a specific embodiment, the sowing seed density of the herbaceous plant A + herbaceous plant B is 20-30 g / m 2 .

[0055] In a specific embodiment, the sowing seed density of each plant of the herbaceous plant A is 3 to 9 g / m 2 .

[0056] In a specific embodiment, the sowing seed density of each plant of the herbaceous plant B is 0.05-2 g / m 2 .

[0057] In a specific embodiment, the shrub species include 2 to 4 species of Sophora japonica, Juniperus chinensis, Hippophae rhamnoides, Caragana spp., and Buddleija truncatula; and the herbaceous plant B preferably includes three species of Medicago truncatula, Astragalus obliquus, and Oxytropis purpurogena.

[0058] In a specific embodiment, the method comprises sowing shrubs + herbaceous plants A + herbaceous plants B at one time.

[0059] In a specific implementation manner, the planting spacing of the shrubs is 1.5m to 2.5m.

[0060] In a specific embodiment, the shrub seedlings are 1 to 3 meters long rooted seedlings, and the top 1 / 3 to 2 / 3 of the stems and leaves are subtracted when the shrubs are planted.

[0061] To further increase the survival rate of shrubs, it is preferred to plant shrubs in clusters, with 3 to 6 shrubs planted in each nest.

[0062] The specific implementation modes of the present invention are further described below in conjunction with embodiments, but the present invention is not limited to the scope of the embodiments.

[0063] Example 1, Comparative Examples 1-3

[0064] Example 1 is applied to the vegetation configuration of ecological restoration of a high-cold mine (3859m above sea level) in Doilungdeqen District, Lhasa. The technical scheme adopted is as follows:

[0065] CT1: According to step 123, plant species suitable for ecological restoration of this mine are selected and the spraying ratio is 7.5g / m 2 , Old sorghum 6.25g / m 2 , Poa annua 5g / m 2 , tall fescue 3.75g / m 2 , Plantain 0.625g / m 2 、Astragalus oblique stem 0.625g / m 2 、Artemisia 0.625g / m 2 , Alfalfa 0.625g / m 2 The shrubs include Sophora japonica, Juniperus chinensis, and Buddaria japonica, with a planting distance of 1.5m-2.5m to ensure that the density of the shrub community is moderate and forms a "fertile island" effect.

[0066] Comparative Examples 1-3 respectively adopt three ecological restoration vegetation configuration modes CT2-CT4.

[0067] CT2: Ecological restoration without shrubs under the same conditions as CT1. The ecological restoration effect of this model is compared with CT1, focusing on evaluating whether the same soil improvement effect can be achieved without planting shrubs.

[0068] CT3: Use other non-native shrubs and trees with herbaceous plants for ecological restoration. The herbaceous plants are configured as in CT1, and spruce and willow are planted in addition. The planting density and configuration of spruce and willow are adjusted according to local climate conditions and ecological requirements. Through this combination, the impact of non-native plants on ecological restoration is evaluated and compared with CT1.

[0069] CT4: Use the traditional plant configuration model of the Tibet Autonomous Region for ecological restoration. The model used is: Cosmos 3g / m 2 , Wild chrysanthemum 3.5g / m2 , tall fescue 6g / m 2 , ryegrass 5g / m 2 , Suaeda salsa 4.5g / m 2 , Setaria 3g / m 2 .

[0070] Ecological restoration was carried out under these four models with other conditions being the same, and the ecological restoration effects were compared after one year.

[0071] Microbial sequence determination method: For each sample, 1.0 g of soil total DNA was accurately extracted. Microbial DNA was extracted from 1.0 g of rhizosphere soil samples using a DNA extraction kit (LABGENE Biotechnology, Chengdu, China). Gene The V3-V4 region of the bacterial 16S rRNA gene was amplified using the primer pair 341F (5'-ACTCCTACGGGGAGGCAGCA-3') and 805R (5'-GGACTACHVGGGTWTCTAAT-3') in a 25-μL reaction volume using a PCR system 9700. The temperature cycle of PCR was as follows: initial denaturation at 98°C for 2 min; 30 cycles of denaturation at 98°C for 15 s; annealing at 55°C for 30 s; extension at 72°C for 30 s; final extension at 72°C for 5 min and end at 4°C. After separation on a 1.2% agarose gel, the PCR product was purified using the QIAquick Gel Extraction Kit (QIAGEN), and the results were quantified using a Qubit@2.0 fluorometer (ThermoScientific). The amplicons were purified and sequenced using the HiSeq 2500PE250 platform (Zhi Ke Company, Chengdu, China).

[0072] Qiime (version 1.7.0, http: / / qiime.org / ) must be used to filter all original 16S rRNA gene sequences. In addition to causing sequencing errors, PCR amplification during high-throughput sequencing can also cause point mutations and chimeric sequences. For example, the chimeric sequences are removed using the uchime method in the mothur software (version 1.31.2, http: / / www.mothur.org / ). Finally, the uclust method is called in Qiime to cluster high-quality sequences at a sequence similarity of 97%, thereby obtaining high-quality sequences and dividing the sequences into different OTUs. The number of OTUs can then be counted. The more OTUs there are, the higher the microbial diversity. The Chao1 index and Shannon-Wiener index of microorganisms can also be used to represent their diversity, and these two indices can be used to compare microbial diversity.

[0073] The indicators measured include vegetation coverage, species diversity, soil nutrient content (soil total nitrogen, available phosphorus and organic matter content), microbial diversity (Chao1 index and Shannon index), moisture content and pH. The results are shown in Table 1 and Table 2 below:

[0074] Table 1 Comparison of soil restoration effects after four different ecological restoration models

[0075]

[0076] Table 2 Comparison of plant and microbial restoration effects after four different ecological restoration models

[0077]

[0078] Note: Different lowercase letters indicate significant differences in soil nutrients and soil bacteria indexes under different plants at the p<0.05 level. Non-native trees planted in group CT3 did not survive.

[0079] Comparison of data before restoration showed that there were small differences in soil, vegetation and microbial indicators among the four groups of models. The CT1 group performed similarly to other models in soil indicators such as organic carbon, total nitrogen, available phosphorus, moisture content, as well as plant coverage and microbial diversity. However, after one year of ecological restoration, the CT1 group achieved comprehensive leadership in all indicators. Soil organic carbon increased from 5.18g / kg to 27.35g / kg, total nitrogen increased significantly from 0.09g / kg to 1.81g / kg, available phosphorus increased from 3.79mg / kg to 18.33mg / kg, and moisture content reached 18.24%, far exceeding other control groups. In addition, the plant coverage of the CT1 group increased significantly from 5.88% to 74.12%, which is at least 25% higher than the CT2, CT3, and CT4 groups, and the plant diversity (Shannon-Wiener index) also reached 1.2, the highest value. In terms of microbial diversity, the Chao1 index and Shannon index of the CT1 group were 2745.33 and 10.46, respectively, which were significantly higher than those of the control group.

[0080] We also further analyzed the plants that formed the "fertilizer island" in the CT1 group by sampling and analyzing the nutrients and enzyme activities of the soil under its shrubs. The specific data are shown in Table 3.

[0081] Table 3 Changes in soil nutrients and enzyme activity after one year of ecological restoration of CT1 vegetation configuration in Example 1

[0082]

[0083] Note: Different lowercase letters indicate significant differences in soil nutrients and enzyme activity indicators under different plants at the p < 0.05 level.

[0084] Sample name grouping in the table: CK-unrestored soil; CB-restored herbaceous rhizosphere soil; SSH-soil under shrub Sophora japonica; SDB-soil under shrub Sophora japonica

[0085] The results showed that the soil under the shrubs of Sophora japonica (SSH) and SDB in the CT1 group showed a significant "fertilizer island" effect, and its soil organic carbon, total nitrogen, available phosphorus and enzyme activity were significantly better than those of the herbaceous rhizosphere soil (CB) and unrestored soil (CK). For example, the soil organic carbon and total nitrogen content under the Sophora japonica shrubs were significantly higher than those of the herbaceous plants, and the activities of sucrase and urease reached the highest levels, respectively, showing its core role in promoting soil nutrient accumulation and improving microbial activity.

[0086] These studies further prove the scientificity and effectiveness of the present invention. By selecting native shrubs suitable for ecological restoration of high-altitude mines and rationally matching them with herbaceous plants, not only an efficient "fertilizer island" area is formed, but also the nutrient level and microbial functional activity of the soil in the restoration area are significantly improved. The core role of shrub plants in soil nutrient accumulation and ecological function restoration makes the CT1 model far superior to other models in terms of ecological restoration effect. This innovative configuration provides an effective and sustainable solution for ecological restoration of high-altitude mines, further highlighting the practicality and promotion value of the present invention in ecological restoration in extreme environments.

Claims

1. A method for ecological restoration of alpine mines, characterized in that: The alpine mine ecological restoration method comprises: A vegetation configuration of shrubs + herbaceous plants A + herbaceous plants B is used to carry out ecological restoration of alpine mines; the herbaceous plants A include at least four of Elymus dactylis, Elymus sibiricus, tall fescue, Poa annua, Stipa purpurogena, Lolium perenne, Artemisia tundraensis, and Kobresia sibiricum; the herbaceous plants B include at least three of Artemisia ordosica, Plantain, Alfalfa, Astragalus obliquus, Taraxacum sinensis, and Oxytropis purpurogenum; the shrub species include at least two of Sophora japonica, Juniperus chinensis, Hippophae rhamnoides, Caragana, and Buddaria japonica.

2. The alpine mine ecological restoration method according to claim 1, characterized in that: The altitude of the alpine mine is 3500 to 4100 meters.

3. The alpine mine ecological restoration method according to claim 1 or 2, characterized in that: The sowing seed density of the herbaceous plant A + herbaceous plant B is 20-30 g / m 2 .

4. The alpine mine ecological restoration method according to claim 3, characterized in that: The sowing seed density of each plant of the herbaceous plant A is 3 to 9 g / m 2 .

5. The alpine mine ecological restoration method according to claim 3, characterized in that: The sowing seed density of each plant of the herbaceous plant B is 0.05-2 g / m 2 .

6. The alpine mine ecological restoration method according to claim 1 or 2, characterized in that: The shrub species include 2 to 4 species of Sophora japonica, Juniperus chinensis, Hippophae rhamnoides, Caragana spp., and Buddaria japonica; the herbaceous plants B preferably include three species of Medicago truncatula, Astragalus obliquus, and Oxytropis purpurogena.

7. The alpine mine ecological restoration method according to claim 1 or 2, characterized in that: The method comprises sowing shrubs+herbaceous plants A+herbaceous plants B at one time.

8. The alpine mine ecological restoration method according to claim 1 or 2, characterized in that: The planting spacing of the shrubs is 1.5m to 2.5m.

9. The alpine mine ecological restoration method according to claim 1 or 2, characterized in that: The seedlings of the shrubs are 1-3 meters long seedlings with roots, and the top 1 / 3-2 / 3 of the stems and leaves are subtracted when the shrubs are planted.

10. The alpine mine ecological restoration method according to claim 1 or 2, characterized in that: When planting shrubs, plant them in clusters, with 3 to 6 shrubs in each nest.

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