Plant-microorganism coupling bank protection method suitable for cities in cold regions

Abstract

The invention belongs to the technical field of riparian zone restoration and treatment, and mainly relates to a plant-microorganism coupling bank protection method suitable for cities in cold regions. The method specifically comprises the following steps: selecting zoysia japonica as revetment vegetation, selecting bacillus subtilis and pseudomonas stutzeri as revetment microorganisms, and constructing a plant-microorganism coupling system to realize natural ecological revetment. The method is a novel ecological bank protection technology integrating multiple functions of river bank reinforcement, water quality purification, soil remediation and the like, the stability of the river bank can be remarkably enhanced, water and soil loss is reduced, water and soil are purified, the ecological environment is continuously improved, and a new thought method is provided for river and lake shoreline remediation; and the method has a good practical engineering application prospect.

Description

Technical Field

[0001] The present invention belongs to the technical field of riverbank restoration and regulation, and in particular relates to a plant-microorganism coupling bank protection method suitable for cities in cold regions. Background Art

[0002] As my country's embankment and bank protection projects continue to advance, numerous ecological problems have emerged. Traditional bank protection projects often utilize reinforced concrete, focusing solely on safety and durability while ignoring their impact on the environment and biodiversity. This not only severely reduces the connection between aquatic and terrestrial ecosystems, but also significantly impairs the water's self-purification capacity and the water storage capacity of riverbanks, affecting the species and distribution of riparian communities and disrupting the structure and function of riverbank ecosystems.

[0003] Existing ecological revetment methods are often only applicable to rivers with slow currents. They pose the risk of gullying and even bank collapse in the face of moderate to high-intensity currents. Plants used for revetment also have low survival rates and poor growth due to environmental factors, seriously impacting their effectiveness. Plant-microbe coupled ecological restoration technology can not only improve environmental quality in the short term but also maintain ecological balance in the long term, demonstrating tremendous potential and application prospects. Summary of the Invention

[0004] The present invention aims to provide a plant-microbe combined restoration method for ecological revetments, thereby improving the scour resistance of riverbanks, thereby reducing soil erosion and enhancing riverbank stability. Furthermore, the method purifies water and soil, removes harmful substances from the water, and continuously improves water quality. (The following sections are the same as the claims and are subject to revision after the claims are finalized.)

[0005] The technical solution adopted by the present invention is a plant-microorganism coupled revetment method suitable for cities in cold regions, comprising the following steps:

[0006] (1) Prepare suitable grass seeds and compound bacterial solution, and pre-treat the grass seeds by germination and other methods;

[0007] (2) Clear weeds and debris near the river bank, level it, apply base fertilizer, and plow it;

[0008] (3) Plant selected flowers from the center to the periphery in the flowerbed area to avoid trampling on the newly sown grass seeds;

[0009] (4) preparing the grass seeds obtained in step 1) after germination pretreatment into a seed matrix and spraying the matrix;

[0010] (5) Cover the sowing area with soil using a soil coverer and use straw mats for covering;

[0011] (6) Maintain and manage the plants, fertilize and water them regularly, and prune them in a timely manner.

[0012] Furthermore, the above-mentioned plant-microorganism coupled revetment method applicable to cities in cold regions is characterized in that, in step (1), the preparation of grass seeds and fungus species includes the following steps:

[0013] 1) Plant seed selection: Based on the specific conditions of the study area, select plant types that are suitable for growth and meet the needs of ecological restoration. Conduct hydroponic experiments on the preliminarily selected plants to simulate the environmental conditions of the study area and determine that Zoysia japonica is the most suitable grass seed.

[0014] 2) Plant seed preparation: Place fresh Zoysia japonica seeds harvested that year into a gauze bag and soak in a 1% sodium hydroxide solution for 36 hours. Rinse with clean water 3-4 times until the sodium hydroxide solution is no longer yellow. Dry in the sun for later use.

[0015] 3) Selection and preparation of composite bacterial suspension: Using the experimental river water as the water sample, strains with strong growth ability and high pollutant degradation capacity were screened as candidate bank protection microorganisms. The microbial species and coupling method were determined through plant-microorganism coupling experiments and preserved in puncture cultures. A portion was taken to prepare a bacterial suspension;

[0016] 4) Germination of plant seeds: Take an appropriate amount of activated bacterial suspension and add it to warm water, soaking Zoysia seeds for 8 hours;

[0017] Furthermore, the above-mentioned plant-microorganism coupled revetment method applicable to cities in cold regions is characterized in that the bacterial species of the composite bacterial solution in step 2) are composed of Bacillus subtilis and Pseudomonas stutzeri;

[0018] Furthermore, the above-mentioned plant-microorganism coupled revetment method applicable to cities in cold regions is characterized in that, in step 2), the bacterial species of the composite bacterial solution are in a volume ratio of Bacillus subtilis to Pseudomonas at 3:1;

[0019] Furthermore, the above-mentioned plant-microorganism coupling revetment method applicable to cities in cold regions is characterized in that, in step (3), the flowers include cherry blossoms and Scutellaria barbata, wherein cherry blossom seedlings are planted in the center position and Scutellaria barbata seedlings are planted in the remaining positions;

[0020] Furthermore, the above-mentioned plant-microorganism coupling revetment method suitable for cities in cold regions is characterized in that, in step (4), the seeds are Zoysia japonica seeds that have been pretreated and hydroponic seedlings, and the sowing rate is about 200-250 kg / hm 2 ;

[0021] Furthermore, the above-mentioned plant-microorganism coupling revetment method suitable for cities in cold regions is characterized in that, in step (4), the seed matrix is obtained by fully mixing 50 parts of seeds, 200 parts of fiber materials, 1 part of methyl cellulose 0.5g, 1 part of green or blue dye and 60 parts of bird droppings and an appropriate amount of water in a container, and spraying with a sprayer;

[0022] Furthermore, the above-mentioned plant-microorganism coupling bank protection method suitable for cities in cold areas is characterized in that, in step (5), the soil covering operation is to use a soil covering device to cover the soil more than twice, with a thickness of 0.2 cm, and to press it with a roller twice. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the ecological bank protection project, where 1 is the ecological bank protection system, 2 is the beauty cherry, 3 is the half-branch lotus, 4 is the seed layer, 5 is the topsoil layer, and 6 is the Zoysia japonica. DETAILED DESCRIPTION

[0024] To make the technical solution and features of the present invention more clear, the present invention will be further explained in detail below with reference to the accompanying drawings and specific embodiments. The specific embodiments described are only used to illustrate the present invention, but the scope of the present invention is not limited thereto.

[0025] 1. Based on the growth characteristics of different types of vegetation, select plants that have strong pollutant treatment capabilities and are suitable for local water quality, soil and other conditions.

[0026] 2. Through cultivation and screening in selective culture medium, we select strains with high degradability and adaptability to the local ecological environment. Based on different strain types and inoculation amounts, we design the optimal ratio of composite strains and prepare composite bacterial agents;

[0027] 3. Compare and determine the optimal coupling method based on the different effects of different plant-microorganism coupling methods on pollutant degradation rates and plant growth conditions.

[0028] Example

[0029] (1) Screening of bank protection plants:

[0030] 1. A riverbank in Northeast China was selected as the experimental site. Based on the selection principles for revetment vegetation, as well as local weather, soil, and water quality, native plant species were selected as much as possible. Investigations revealed that the following plants were suitable for the experimental site: Zoysia japonica, Corona minor, Trifolium repens, Poa annua, Chlorophytum corymbiferum, Plantain, and Tall Fescue.

[0031] 2. Using soil and water samples from the study riverbank, conduct hydroponic experiments on the seven plants mentioned above. The specific steps are as follows:

[0032] A truncated cone plastic flower pot with an upper diameter of about 15 cm, a lower diameter of 25 cm, and a height of 20 cm was used as the test container. Ten plants of each of the seven species were selected, cleaned of soil, and freed of dead leaves, and then transplanted into the flower pot. The test began after pre-cultivation for 2 weeks and weighing of the mass.

[0033] During the experiment, the water was rainwater from the Baisha River, 15L each time. The experiment lasted about 3 months. Distilled water was used every day to replenish the water lost due to evaporation. Three replicates were set for each plant.

[0034] ++ indicates strong growth, + indicates average growth, and - indicates weak growth.

[0035] The growth activity of various plants is shown in Table 1:

[0036] Table 1

[0037]

[0038] 3. As can be seen from the table, the grass species selected for the plant-microorganism coupling method applied to ecological revetment of the present invention are Zoysia japonica or Poa annua.

[0039] (2) Screening of bank protection microorganisms:

[0040] 1. A water sample obtained by mixing sewage from a sewage treatment plant upstream of the study area and rainwater from the river bank was stored at room temperature.

[0041] 2. Primary screening: The isolated bacteria were streaked onto STTP-urea selective medium using the plate streak method and cultured at 25°C for 48 hours. The bacterial growth was recorded and bacteria that grew well within 48 hours were selected as strains for rescreening.

[0042] 3. Secondary screening: The strains obtained from the initial screening were inoculated into a liquid culture medium to screen for strains with strong COD degradation capabilities. The microorganisms selected for the plant-microorganism coupling method for ecological revetment in the present invention were identified as Bacillus subtilis and Pseudomonas stutzeri.

[0043] 4. According to different bacterial strain types and inoculation amounts, the two screened bacterial communities are compounded, the optimal ratio of the composite bacterial strains is designed, and the composite bacterial agent is prepared.

[0044] 5. Inoculate the composite bacterial agent into the water sample and then measure the changes in COD content in each group

[0045] The removal rates of COD by each group of composite bacteria are shown in Table 2:

[0046] Table 2

[0047]

[0048] 5. As can be seen from the table, the optimal inoculation amount of the composite bacteria is 3ml of Bacillus subtilis and 1ml of Pseudomonas stutzeri.

[0049] (3) Plant-microbe coupling:

[0050] 1. Conduct simulation experiments in the laboratory to combine the selected plants and microorganisms to determine the coupling method with the best treatment effect. The specific steps are as follows:

[0051] 1) Set up groups I to IX, namely, the bluegrass group, the zoysia grass group, the zoysia grass + Bacillus subtilis group, the bluegrass + Bacillus subtilis group, the zoysia grass + Pseudomonas stutzeri group, the bluegrass + Pseudomonas stutzeri group, the zoysia grass + Bacillus subtilis + Pseudomonas stutzeri group, and the bluegrass + Bacillus subtilis + Pseudomonas stutzeri group. Set up three parallel experiments for each group;

[0052] 2) Soak the plant seeds in a bacterial suspension of appropriate concentration for several days and fill the planting trough with soil in advance;

[0053] 3) Sow the soaked seeds of each group evenly in each planting trough, sow slightly densely, and cultivate under suitable growth conditions;

[0054] 4) When the plants grow to about 5cm, pull out some of them, leaving an appropriate amount of plants with good growth;

[0055] 5) Add water at a flow rate of 0.6L / s for one hour every seven days, and add water at a flow rate of 0.15L / s for ten minutes every day.

[0056] 6) Collect treated water samples, measure various indicators and observe the growth of plants and microorganisms.

[0057] The determination methods of each indicator are shown in Table 3:

[0058] Table 3

[0059] Analytical indicators Analytical methods CODcr Rapid digestion method Total phosphorus Ammonium molybdate spectrophotometry Total nitrogen Potassium persulfate digestion-UV spectrophotometry Microbial activity Fluorescein diacetate method

[0060] 2. The results of the plant-microorganism coupling experiments in each group are shown in Table 4:

[0061] Table 4

[0062]

[0063] ++ means strong growth, + means average growth, - means weak growth

[0064] 3. Through the parallel comparison of each group of factors, it is obvious that the treatment effect of group VIII (Zodiaceae+Bacillus subtilis+Pseudomonas stutzeri group) is relatively better.

[0065] (4) Construction of bank protection projects:

[0066] 1. Preparation of grass seeds and fungus strains, the specific steps are as follows:

[0067] 1) Plant seed preparation: Place fresh Zoysia japonica seeds harvested that year into a gauze bag, soak in a 1% sodium hydroxide solution for 36 hours, rinse with clean water 3-4 times until the solution is no longer yellow, and sun-dry for later use;

[0068] 2) Preparation of composite bacterial suspension: The selected Bacillus subtilis and Pseudomonas aeruginosa were prepared into a bacterial suspension at a volume ratio of 3:1;

[0069] 3) Germination of plant seeds: Take an appropriate amount of activated bacterial suspension and add it to warm water, and soak the Zoysia seeds for 8 hours.

[0070] 2. Site leveling and preparation, the specific steps are as follows:

[0071] 1) Clear weeds and debris near the riverbank, level the land, apply base fertilizer, and till the soil. At the same time, replace the soil. You can also apply high-quality fertilizer to enhance soil fertility.

[0072] 2) Plant the cherry blossoms from the four sides inward and outward, and plant the half-flowered lotus on the inner side. Plant the seedlings with soil at a distance of two fists and apply water and fertilizer.

[0073] 3. Preparation and sowing of seed matrix, the specific steps are as follows:

[0074] 1) 50 parts by weight of accelerated-germination seeds, 200 parts by weight of hemp fiber, 1 part by weight of methylcellulose, 1 part by weight of green or blue dye, 60 parts by weight of guano, and an appropriate amount of water are thoroughly mixed in a container to obtain a seed matrix.

[0075] 2) Before sowing, evenly spread 3kg / m2 of mature organic fertilizer on the research plot. 2 , compound fertilizer 0.08kg / m 2 , and then till the soil.

[0076] 3) Choose windless or light wind weather and use a sprayer for sowing when the soil temperature is around 30℃.

[0077] 4) After sowing, cover the sowing area with soil using a soil coverer for more than 2 times, with a thickness of 0.2 cm, and press it down with a 50-80 kg roller for 2 times, and use straw mat for covering.

[0078] 4. Later maintenance and management, the specific steps are:

[0079] 1) Watering: Water frequently after sowing to ensure the soil is moist. Carry out the first sprinkler irrigation within 24 hours after sowing, spray the soil 5-10 cm deep, and spray 2-3 times a day until germination; then sprinkler irrigation every 3-5 days until the vegetation is fully grown.

[0080] 2) Pruning: Weed control should be carried out 3-5 times during the seedling stage, using a combination of chemical control and manual removal to remove weeds. Pest and disease control should be done well during the seedling stage, and vegetation should be pruned at appropriate times.

[0081] 3) Topdressing: When the grass grows to the 5-leaf stage, apply quick-acting nitrogen (4-8g / m 2 ) for topdressing, and the specific fertilizer applied is mainly decomposed organic fertilizer.

Claims

1. A plant-microorganism coupled bank protection method suitable for cities in cold regions, characterized in that: The steps include: 1) Prepare suitable grass seeds and compound bacterial solution, and pre-treat the grass seeds for germination; 2) Clear weeds and debris near the river bank, level the land, apply base fertilizer, and till the land; 3) Plant selected flowers from the center to the periphery in the flowerbed area to avoid trampling on the newly sown grass seeds; 4) preparing a seed matrix from the grass seeds pretreated by germination obtained in step 1) and spraying the matrix; 5) Cover the sowing area with soil using a covering device and use straw mats; 6) Maintain and manage the plants, fertilize and water them regularly, and prune them in time.

2. The plant-microorganism coupled revetment method suitable for cities in cold regions according to claim 1 is characterized in that: Step 1) is specifically as follows: 1) Grass seed preparation: Place fresh Zoysia or Poa annua seeds harvested that year into a gauze bag and soak in a 1% sodium hydroxide solution for 36 hours. Rinse with clean water 3-4 times until the solution is no longer yellow. Dry in the sun for later use. 2) Preparation of composite bacterial suspension: Prepare bacterial suspension from the bacterial strains stored in the puncture culture; 3) Germination of plant seeds: Take an appropriate amount of activated bacterial suspension and add it to warm water, and soak Zoysia japonica or Poa annua seeds for 8 hours.

3. The plant-microorganism coupled revetment method suitable for cities in cold regions according to claim 2, characterized in that: In step 1), the bacterial species of the composite bacterial solution are composed of Bacillus subtilis and Pseudomonas stutzeri.

4. The plant-microorganism coupled revetment method suitable for cities in cold regions according to claim 3 is characterized in that: In step 1), the bacterial species of the composite bacterial solution are in a volume ratio of Bacillus subtilis to Pseudomonas at 3:

1.

5. The plant-microorganism coupled revetment method suitable for cities in cold regions according to claim 1 is characterized in that: In step 3), the flowers include cherry blossoms and Scutellaria barbata, wherein cherry blossom seedlings are planted in the center position and Scutellaria barbata seedlings are planted in the remaining positions.

6. The plant-microorganism coupled revetment method suitable for cities in cold regions according to claim 1 is characterized in that: In step 4), the sowing rate is 200-250kg / hm2. 2 .

7. The plant-microorganism coupled revetment method suitable for cities in cold regions according to claim 1 is characterized in that: In step 4), the seed matrix is prepared by fully mixing 50 parts of seeds, 200 parts of fiber materials, 1 part of methyl cellulose (0.5 g), 1 part of green or blue dye, 60 parts of bird droppings and an appropriate amount of water in a container and spraying the mixture using a sprayer.

8. The plant-microorganism coupled revetment method suitable for cities in cold regions according to claim 1 is characterized in that: In step 5), the soil covering operation is to use a soil covering device to cover the soil for more than 2 times, with a thickness of 0.2 cm, and to press it with a roller for 2 times.

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