A method for improving afforestation survival rate by promoting mycorrhizal fungal infection through electrically driven earthworms
By using an electrically driven coupling system between earthworms and ectomycorrhizal fungi, the movement of earthworms is accelerated by the electric power system, which promotes mycorrhizal fungal infection. This solves the problem of low survival rate of trees in difficult sites and achieves efficient soil improvement and vegetation restoration.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHANGHAI JIAOTONG UNIV
- Filing Date
- 2024-12-24
- Publication Date
- 2026-05-26
AI Technical Summary
Difficult sites have poor soil, low survival rate of secondary forest trees, and traditional soil improvement techniques are not effective and cause environmental pollution. There is a lack of targeted soil improvement techniques.
An electric-driven coupling system of earthworms and ectomycorrhizal fungi was adopted. The electric power system accelerated the movement of earthworms and promoted the infection of mycorrhizal fungi. A tubular electric power system was set up around the tree trunk, and the power was applied to promote the spread of earthworms and mycorrhizal fungi in difficult sites.
It significantly increased the infection rate of ectomycorrhizal fungi at tree root tips, improved tree survival rate and soil organic matter content, achieved environmentally friendly soil improvement effects, and reduced afforestation costs.
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Figure CN119605590B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of forestry technology, and in particular to a method for improving afforestation survival rate by promoting mycorrhizal fungal infection through electrically driven earthworms. Background Technology
[0002] Difficult site afforestation is characterized by infertile soil, low organic matter content, and nutrient deficiency, which is detrimental to tree growth. Furthermore, afforestation in difficult sites must address the poor soil structure of secondary forest sites, such as salinization, compaction, and pollution by organic matter and heavy metals. Secondary forest trees severely restrict root development, leading to difficulties in soil carbon storage and low tree survival rates.
[0003] my country has a large area of difficult-to-plant sites with low afforestation survival rates, which seriously restricts the growth of forest resources and the improvement of the ecological environment. Afforestation on difficult-to-plant sites is an important requirement for the construction of forest cities. How to consolidate the survival rate of secondary forest trees and promote soil carbon storage is a bottleneck problem for the restoration of ecosystems in difficult-to-plant sites. Existing auxiliary technologies for afforestation on difficult-to-plant sites mainly include soil-improvement, water-collecting afforestation, mixed afforestation, and enhanced fertilization. Traditional technologies have the following problems: (1) the soil improvement effect is not obvious and slow, and cannot meet the growth needs of trees; (2) a large amount of chemical fertilizers pollute the environment; (3) there is a lack of comprehensive technologies that simultaneously promote soil properties and tree growth in difficult-to-plant sites.
[0004] Patent application CN202211550483.3 discloses a method for biological improvement of urban green space soil, specifically including the following steps: S1, soil property determination; S2, earthworm bait placement and inoculation; S3, strain inoculation; S4, simultaneous inoculation of earthworms and strains; S5, data statistics and formulation of soil improvement plan. By inoculating the soil with different strains and earthworms, and then conducting sequential soil tests, the optimal soil improvement plan is formulated based on the statistical analysis of the test data. This plan can more accurately and specifically formulate a soil improvement plan based on the actual data results, thereby ensuring the improvement of the soil environment, improving soil properties, and increasing the survival rate of seedlings, thus reducing the need for replanting and replacement of seedlings during the warranty period and reducing the economic burden on landscaping construction units. However, this technology does not consider the characteristics of ectomycorrhizal fungi, namely, these microorganisms must infect the root tips of trees to form ectomycorrhizae. In this technology, earthworms move slowly and do not necessarily move to deeper soil layers. This can easily lead to problems such as ectomycorrhizal fungi not adapting to the surface soil environment, sinking slowly, or losing activity before reaching deeper soil layers. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a method for promoting mycorrhizal fungal infection and improving afforestation survival rate based on electrically driven earthworms, thereby increasing the infection rate of ectomycorrhizal fungi at tree root tips, promoting the growth and health of trees in difficult sites and improving afforestation survival rate, so as to achieve the purpose of soil carbon sequestration and sequestration.
[0006] The objective of this invention can be achieved through the following technical solution: a method for improving afforestation survival rate by promoting mycorrhizal fungal infection based on electrically driven earthworms, comprising the following steps:
[0007] (1) Select mycorrhizal fungi and earthworms with symbiotic relationship to construct a mycorrhizal-earthworm coupling system;
[0008] (2) Set up an electric power system: Set up an electric power system around the tree trunk, and put the mycorrhizal-earthworm coupling system described in step (1) into the electric power system and turn on the power.
[0009] Further, in the mycorrhizal-earthworm coupling system described in step (1): 5-30 earthworms are added per kilogram of mycorrhizal fungal agent, and each kilogram of mycorrhizal fungal agent contains (1-100)*10 ectomycorrhizal fungi. 9 indivual.
[0010] Furthermore, the earthworms selected are earthworm species adapted to difficult site environments;
[0011] The mycorrhizal fungi are ectomycorrhizal fungi.
[0012] Furthermore, the earthworm is *Pheretima aspergillum*; and the mycorrhizal fungus is the ectomycorrhizal fungus *Lactarius aquosus*.
[0013] Furthermore, the electro-powered system is a tubular electro-powered system, including a tube, conductive rods attached to the inner wall of the tube, a battery, the positive and negative terminals of the battery being connected to the conductive rods respectively, and a mycorrhizal-earthworm coupling system being filled inside the tube.
[0014] Furthermore, the battery is a 24V dry cell battery with a maximum current of 4A.
[0015] Furthermore, a nylon mesh is provided at the bottom of the tube, and the battery is placed at the top of the tube.
[0016] Furthermore, the power-on time in step (2) is 1-3 hours.
[0017] In step (2), the electric power system is 1-5m away from the tree trunk.
[0018] Compared with the prior art, the present invention has the following advantages and beneficial effects:
[0019] (1) This invention utilizes the principle of accelerating earthworm movement with an electric field to promote the spread of ectomycorrhizal fungi. It selects mycorrhizal fungi with symbiotic relationships and earthworms adapted to difficult site environments to improve the spread rate of mycorrhizal fungi and the infection rate of tree root tips. It also adds electric power and isolation devices to accelerate the movement speed of earthworms and the movement speed of ectomycorrhizal fungi inoculum.
[0020] (2) The mycorrhizal-earthworm coupling technology used in this invention is used to improve the survival rate of afforestation in difficult sites. By selecting mycorrhizal fungi with symbiotic relationships and earthworms adapted to difficult site environments, a mycorrhizal-earthworm coupling system is constructed and applied to afforestation in difficult sites. This can increase the infection rate of ectomycorrhizal fungi at the root tips of trees, promote the growth and health of trees in difficult sites and improve the survival rate of afforestation, so as to achieve the purpose of soil carbon sequestration and sequestration.
[0021] (3) Compared with traditional methods of directly increasing water and fertilizer, this invention has the advantages of low cost, strong operability, environmental friendliness and high added value, and has good environmental, economic and social benefits, providing a new method for reducing afforestation and maintenance costs. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the system structure of the present invention;
[0023] Explanation of markings in the diagram:
[0024] 1-Tube, 2-Nylon mesh, 3-Conductive rod, 4-Battery. Detailed Implementation
[0025] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.
[0026] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0027] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0028] In the following embodiments, unless otherwise specified, the raw materials or processing techniques are conventional commercially available raw materials or conventional processing techniques in the art. Unless otherwise specified, the functional components or structures are conventional components or conventional structures used in the art to achieve the corresponding functions.
[0029] This invention utilizes symbiotic mycorrhizal fungi and earthworms adapted to challenging site environments. Based on the principle of electric field-induced earthworm activity, it promotes the diffusion and inoculation of ectomycorrhizal fungi, thereby increasing the ectomycorrhizal fungal infection rate at tree root tips. This invention is applied to afforestation in challenging sites and includes the following steps:
[0030] (1) Selection of mycorrhizal fungi: Select ectomycorrhizal fungi that can form a symbiotic relationship with tree roots.
[0031] (2) Select earthworm species that are adapted to difficult site environments.
[0032] (3) Construct a tubular electric power system.
[0033] (4) Mix the mycorrhizal fungi and earthworms obtained in (1) and (2) in a certain proportion, put them into (3), and use them in the secondary forest stand.
[0034] Example 1
[0035] Due to long-term iron ore mining, the Shilu iron ore mining area in Hainan Province has suffered from severe heavy metal (iron, nickel, etc.) pollution in the soil, resulting in soil degradation, vegetation destruction, and ecological damage.
[0036] In this embodiment, mycorrhizal-earthworm coupled electrodynamic technology is used to restore the ecology of the Shilu iron ore area in Hainan Province. The specific method is as follows:
[0037] (1) Selection of mycorrhizal fungi and earthworms:
[0038] Ectomycorrhizal fungi adapted to the local tropical climate were selected. In this embodiment, Lactarius aquosus, a common ectomycorrhizal fungus of tropical trees and plants, was chosen.
[0039] Earthworm species adapted to local climate and soil conditions are selected; in this example, *Pheretima apergillum* is used.
[0040] (2) Cultivation of mycorrhizal fungi and earthworms
[0041] Ectomycorrhizal fungi suitable for tropical environments were screened and propagated in the laboratory. A liquid inoculum of ectomycorrhizal fungi was prepared by fermentation on potato dextrose agar (PDA) medium (12 g / L potato extract, 20 g / L glucose, pH 5.6 ± 0.2) under anaerobic conditions at 30°C. The liquid inoculum was then mixed with soil substrate that had undergone high-temperature aerobic composting (70°C aerobic composting for one week, followed by three months of maturation) at a mass ratio of 1:10 (inoculum:substrate) to form an inoculum of ectomycorrhizal fungi.
[0042] Earthworms are cultivated at the earthworm breeding base to ensure their health and reproduction.
[0043] (3) Construction of the mycorrhizal-earthworm coupling system
[0044] The ectomycorrhizal fungal inoculum prepared in step (2) was mixed with earthworms in the following proportion to form a mycorrhizal-earthworm coupling system: 20 earthworms + 1 kg of the ectomycorrhizal fungal inoculum prepared in step (2) (the concentration of the ectomycorrhizal fungus *Macrothecorrhizalum* was approximately 10). 9 (per g).
[0045] (4) Constructing a tubular electric power system
[0046] like Figure 1 As shown: An electric power system is randomly deployed within a distance of 1-5 meters from the tree trunk: PVC pipe 1 with a diameter of 20cm and a length of 20cm is selected, and a nylon mesh 2 with a hole diameter of 0.5cm is provided at the bottom, which serves to filter and protect. The nylon mesh has the characteristics of high toughness, good elasticity, corrosion resistance, and oil resistance. Therefore, the nylon mesh with this hole diameter can be used to prevent larger particles of material from leaking out, while allowing earthworms and mycorrhizal materials to pass through. Conductive rods 3 are attached to the inner wall of the PVC pipe, and the mycorrhizal-earthworm coupling system constructed in step (3) is added. A battery 4 is placed directly on the PVC pipe 1, and the positive and negative terminals are connected to dry batteries (24V, maximum current 4A). The power is applied for 2 hours, and the dry batteries are placed inside the pipe 1 to prevent earthworms from escaping upwards.
[0047] (5) Implementation Results
[0048] 1. Soil remediation:
[0049] In the difficult site of the Shilu iron ore area in Hainan Province, which is severely polluted by heavy metals such as iron and nickel, 5-year-old Pinus latteri seedlings were planted. A tubular electro-powered system was set up 1 meter away from the trunk, and earthworms and ectomycorrhizal fungi inoculants were added. The amount added was controlled to be 20 earthworms + 1 kg of the ectomycorrhizal fungi inoculant from step (2) above (the concentration of the ectomycorrhizal fungus *Macrothecorrhizalum* was about 10). 9 The inoculation process was completed after 2 hours of energization (number per g). Soil and root tips were collected one year later to assess the inoculation effect. Root tip infection rate was determined using electron microscopy, soil organic matter content was determined using incineration, and the activity of mycorrhizal fungi and earthworms was analyzed.
[0050] Ectomycorrhizal fungal infection rate = Number of mycorrhizal segments / Number of observed root segments
[0051] 2. Vegetation restoration:
[0052] Afforestation survival rate (%) = (Number of surviving trees / Total number of afforested trees) × 100%
[0053] Comparative Example 1
[0054] A difficult site with severe pollution of heavy metals such as iron and nickel in the Shilu iron ore area of Hainan Province was selected and left untreated as a control example 1.
[0055] Comparative Example 2
[0056] The rest is the same as in Example 1, except that only earthworms and mycorrhizae are added, and no electricity is applied, that is, no electricity is applied in step (4).
[0057] The results are shown in Table 1 below:
[0058] Table 1. Changes in soil organic matter, tree survival rate, and mycorrhizal infection rate in different treatment groups
[0059]
[0060] As shown in Table 1 above, the treatment method in Example 1 resulted in a higher soil organic matter content, increasing the organic matter content of the mining area soil by more than 10% compared to Comparative Example 1. Compared to Comparative Example 1, Example 1 also showed higher afforestation survival rate and mycorrhizal infection rate. Compared to Comparative Example 2, both soil organic matter and afforestation survival rate were also higher.
[0061] Examples 2-5
[0062] The rest is the same as in Example 1, except that the number of earthworms added per kilogram of ectomycorrhizal fungal inoculum in step (3) was 5, 10, 20, and 30, respectively. The effect of adding different numbers of earthworms on the mycorrhizal infection rate was detected, and the results are shown in Table 2 below:
[0063] Table 2. Effect of adding different amounts of earthworms on mycorrhizal infection rate (calculated per kilogram of inoculum)
[0064]
[0065] As can be seen from Table 2 above, adding earthworms is beneficial to increasing the mycorrhizal infection rate. When 5-30 earthworms are added, the ectomycorrhizal infection rate is significantly increased by 3.2-14%.
[0066] In summary, the treatment of "adding electric power + mycorrhizae and earthworms" can increase soil organic matter content by more than 10%, improve forest survival rate by more than 30%, and increase the root tip infection rate of ectomycorrhizal fungi by more than 50%. Furthermore, adding 20 earthworms per kilogram of inoculum achieves the optimal infection rate.
[0067] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.
Claims
1. A method for improving afforestation survival rate by promoting mycorrhizal fungal infection through electrically driven earthworms, characterized in that, Includes the following steps: (1) Select mycorrhizal fungi and earthworms with a stable symbiotic relationship to construct a mycorrhizal-earthworm coupling system; the mycorrhizal fungi are ectomycorrhizal fungi; (2) Setting up an electric power system: Set up an electric power system around the tree trunk, put the mycorrhizal-earthworm coupling system described in step (1) into the electric power system, and turn on the power; the electric power system is a tubular electric power system, including a tube, a conductive rod attached to the inner wall of the tube, a battery, the positive and negative poles of the battery are respectively connected to the conductive rod, and the mycorrhizal-earthworm coupling system is filled in the tube; the battery is a 24V dry cell battery with a maximum current of 4A and an energizing time of 1-3h, and the electric power system is 1-5m away from the tree trunk.
2. The method for improving afforestation survival rate by promoting mycorrhizal fungal infection based on electrically driven earthworms according to claim 1, characterized in that, In the mycorrhizal-earthworm coupling system described in step (1): 5-30 earthworms are added per kilogram of mycorrhizal fungal agent, and each kilogram of mycorrhizal fungal agent contains (1-100)*10 ectomycorrhizal fungi. 9 indivual.
3. The method for improving afforestation survival rate by promoting mycorrhizal fungal infection based on electrically driven earthworms according to claim 1, characterized in that, The earthworms used are earthworm species that are adapted to difficult site environments.
4. The method for improving afforestation survival rate by promoting mycorrhizal fungal infection based on electrically driven earthworms according to claim 3, characterized in that, The earthworm is *Pheretima aspergillum*; the mycorrhizal fungus is the ectomycorrhizal fungus *Macrothecospora* (…). Lactarius aquosus ).
5. The method for improving afforestation survival rate by promoting mycorrhizal fungal infection based on electrically driven earthworms according to claim 1, characterized in that, The tube has a nylon mesh at the bottom and the battery is placed at the top of the tube.