A river water ecological restoration method based on ecological floating carpet

Abstract

The present invention belongs to the field of water ecological restoration, and specifically relates to a river water ecological restoration method based on an ecological floating carpet, which utilizes the ecological floating carpet, fish, and microorganisms to construct an ecological restoration system to improve river water bodies. The ecological floating carpet includes plants, carriers, nylon nets, planting substrates, and inorganic fillers. The selected plants are inoculated with pollutant-degrading bacteria and domesticated through tolerance experiments. The inorganic fillers are suspended through the nylon net on the lower part of the ecological floating carpet. The nylon net is pre-filmed to form a layer of yellow-brown biofilm on its surface. The planting substrate is a combination of multiple types of chitosan-potassium alginate-coated melamine polyurethane composite foam, biochar, scrap iron, and alum sludge ceramsite. The plants provided by the present invention have strong tolerance and can efficiently adsorb and degrade pollutants. The planting substrates provided by the present invention promote each other and efficiently adsorb pollutants. The ecological floating carpet, fish, and microorganisms constructed by the present invention constitute an ecological breeding technology, which can promote the formation of a healthy food chain system in the receiving river.

Description

Technical Field

[0001] The present invention belongs to the technical field of water ecological restoration, and in particular relates to a river water ecological restoration method based on an ecological floating blanket. Background Art

[0002] Wastewater discharge from industrial parks is characterized by differences in industry characteristics, large fluctuations in water quality and quantity, high COD concentrations, and complex components. Industrial wastewater, mainly from papermaking, food processing, petrochemicals, and printing and dyeing, often contains a large amount of difficult-to-degrade organic matter. According to the current domestic sewage treatment plant discharge standards, the effluent treated is "engineered water" that has been treated through engineering methods and the addition of chemical agents. The discharged organic pollutants are difficult to degrade in the environment, affecting the stability of the ecological environment. At the same time, they will accumulate in aquatic organisms and cause them poisoning. The tail water of industrial park wastewater after treatment by sewage treatment plants is usually treated by direct discharge. Although this type of tail water meets the discharge standards, it is still a source of pollution for the surface water environment. Discharge into natural water bodies is not conducive to the quality of the surface water environment.

[0003] This type of wastewater contains emerging pollutants such as phenol and its derivatives, microplastics, and per- and polyfluoroalkyl substances (PFAS). Phenol and its derivatives are aromatic compounds that are biotoxic and difficult to degrade, making them common contaminants in industrial wastewater. Everyday plastics, exposed to weathering, sunlight, and abrasion, break down into smaller fragments. Plastics smaller than 5 mm are classified as microplastics. These microplastics enter sewage treatment plants with wastewater, and unremoved microplastics are discharged into local waterways with wastewater treatment plant wastewater. While primary wastewater treatment can remove larger particles, the lack of specialized removal processes makes wastewater treatment plants a significant source of microplastic pollution. PFAS are widely used across various industries. Due to their extremely high thermal and chemical stability, PFAS persist in the environment. PFAS enter the aquatic environment through various pathways, including direct discharge through industrial and domestic wastewater, as well as indirect pathways such as landfill leachate and dust, ultimately contaminating wastewater treatment plants. While traditional wastewater treatment processes can remove a certain amount of PFAS, residual PFAS can still be found in wastewater wastewater. Tertiary treatment processes such as chlorination, ozone oxidation, and ultraviolet disinfection are also unable to effectively remove PFAS and have negative removal effects.

[0004] Ecological floating blankets are a novel water remediation technology developed from traditional constructed wetlands. Due to their low investment, high efficiency, no need for additional land, strong adaptability to water depth, flexible operation, simple maintenance, and green economy, they are becoming increasingly popular and widely used in landscape water remediation projects. In an ecological floating blanket system, the upper portion is covered with lush vegetation, while the lower portion is a well-developed plant root system, which is covered with a rich biofilm. The carrier in the ecological floating blanket system provides buoyancy for the plants, and the medium acts as a anchor for the plants. Through the combined action of plant absorption, microbial assimilation and transformation, and adsorption and precipitation, the ecological floating blanket can purify the water system. Currently, ecological floating blankets are widely used to purify landscape water and traditional pollutants, but there are no reports on their effectiveness in purifying these emerging pollutants.

[0005] Therefore, it is necessary to provide an improved technical solution to the above-mentioned deficiencies in the prior art. Summary of the Invention

[0006] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a river water ecological restoration method based on an ecological floating blanket.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] A river water ecological restoration method based on an ecological floating carpet, which uses an ecological floating carpet, fish, and microorganisms to construct an ecological restoration system to improve river water bodies, includes the following steps:

[0009] S1. River channel selection: The river channel is the receiving water body for the tailwater of the industrial wastewater treatment plant. A small fence facility is used to isolate the treatment area in the river channel. The water flow velocity in the treatment area does not exceed 1m / s.

[0010] S2. Preparation of Ecological Floating Blankets: The ecological floating blankets include plants, carriers, nylon mesh, planting substrates, and inorganic fillers. The plants in the ecological floating blankets are a combination of irises, windmill grass, water spinach, reeds, and giant hyacinths. The selected plants have been inoculated with pollutant-degrading bacteria and acclimated through tolerance experiments.

[0011] The carrier of the ecological floating blanket is a floating mat made of EVA, on which a planting basket is installed to fix the roots of the plants. The inorganic filler is suspended from the bottom of the floating mat through a nylon mesh. The inorganic filler is a combination of zeolite and sponge iron. The nylon mesh holding the inorganic filler is pre-filmed to form a layer of yellow-brown biofilm on its surface. The planting matrix is ​​a combination of chitosan-potassium alginate coated melamine polyurethane composite foam, biochar, scrap iron, and alum sludge ceramsite.

[0012] S3. Selection of fish in the water: Fish with different purifying functions, such as those that can ingest organic debris and phytoplankton, and have different habits and feeding characteristics, should be selected from a combination of silver carp, bighead carp, and catfish.

[0013] S4. Restoration of river water ecology: Six months after the ecological restoration system constructed by ecological floating carpet, fish and microorganisms was put into use, the river water environment was improved.

[0014] Furthermore, the planting density of plants in the ecological floating carpet is 1kg seedlings / m 2 The planting ratio of iris, windmill grass, water spinach, reed and giant caltrop is (1.4-1.6): (1.1-1.3): (0.9-1.1): (1.4-1.6): (0.9-1.0); the number ratio of catfish, silver carp and bighead carp is 1:1:1, the weight of fish released is 0.3-0.5 kg / fish, and the stocking density is 9 fish / m 2 .

[0015] Furthermore, the mass ratio of zeolite to sponge iron in the inorganic filler is (0.8-1.2):1.

[0016] Furthermore, the plant acclimation experiment in step S2 includes the following steps:

[0017] (1) Bacillus velezensis, Pseudomonas stutzeri, and Bacillus cereus were cultured in an inorganic salt medium containing 200 mg / L phenol for 24 h until OD 660 The optical density of each bacterial strain was adjusted to a value between 0.8 and 1.2. The cells were harvested by centrifugation and then resuspended in 0.9% (w / v) NaCl solution. The optical density of each bacterial strain was adjusted to a cell number of not less than 1.0 × 10 7 CFU / mL, the three bacterial strain suspensions were mixed in a ratio of 1:1:1 to prepare 150 mL of inoculum;

[0018] (2) Prepare 20L of clean water, add a certain amount of rooting agent to the water to increase the survival rate of plants, and culture healthy plant seedlings in the clean water for 20 days;

[0019] (3) The cultured plant seedlings were transferred to a contaminated water body with a phenol concentration of 300 mg / L. After sterilizing the contaminated water body and the surface of the plant roots, 150 ml of bacterial inoculum was added to the contaminated water body and the plant seedlings were cultured for 10 days.

[0020] Furthermore, the nylon mesh pre-filming treatment process in step S2 is as follows:

[0021] (1) After soaking the nylon net in clean water for 30 hours, hang it in a container containing 50L of test water; the test water is the water taken from the river in step S1;

[0022] (2) A composite bacterial preparation was added to the test water body, aerated, and pre-filmed, waiting for the formation of a biofilm on the surface of the nylon mesh; the composite bacterial preparation was prepared by culturing and drying Bacillus subtilis, Bacillus lysinicola, and Microbacterium esters, and then mixing them in a ratio of 1:1:1, with an addition amount of 0.5 g / L.

[0023] Furthermore, the preparation steps of the chitosan-potassium alginate coated melamine polyurethane composite foam are as follows: 1×1×1 cm 3 The melamine polyurethane foam was immersed in a chitosan-acetic acid solution and ultrasonicated for 30 minutes to obtain a first product; the first product was then immersed in a 1.0 g / L potassium alginate solution, allowed to stand at room temperature for 1 hour, and then removed from the solution to obtain a second product; finally, the second product was immersed in a 6% calcium chloride solution for 30 hours and naturally dried to produce a chitosan-potassium alginate coated melamine polyurethane composite foam;

[0024] The biochar is made by pyrolysis of sterilized plant raw materials at 500-600°C and stable carbonization for 2 hours;

[0025] The scrap iron is in a spiral shape and has a length of 2-3 cm;

[0026] The raw material of the alum sludge ceramsite is taken from the alum sludge of the water plant; the alum sludge is kneaded into a ball, air-dried to constant weight at room temperature, placed in a muffle furnace at 600°C for 6 minutes, taken out, and cooled at room temperature for 18 hours to prepare the alum sludge ceramsite. The diameter of the ceramsite is 0.5-0.6 cm, the average pore size is 3.5 mm, and the average specific surface area is 250 m 2 / g.

[0027] In one embodiment, 50 chitosan-potassium alginate coated melamine polyurethane composite foams, 100 g of biochar in a mesh bag, and 900 g of iron filings are placed in each planting basket.

[0028] In another embodiment, 50 chitosan-potassium alginate coated melamine polyurethane composite foams and 1000 g alum sludge ceramsite are placed in each of the planting baskets.

[0029] In another embodiment, 500 g of alum sludge ceramsite, 50 g of biochar contained in a mesh bag, and 450 g of iron filings are placed in each of the planting baskets.

[0030] In another embodiment, 50 chitosan-potassium alginate coated melamine polyurethane composite foams, 50 g of biochar and 450 g of iron filings, and 500 g of alum sludge ceramsite contained in a mesh bag are placed in each of the planting baskets.

[0031] The beneficial effects of the present invention are:

[0032] 1. The plants provided by the present invention have strong tolerance and are highly efficient in adsorbing and degrading pollutants;

[0033] Through laboratory acclimation experiments, five plant species have been trained to improve their tolerance to pollutants. When surviving in polluted water, they can degrade and absorb pollutants, insoluble substances, and heavy metals. Their roots extend deeply into the polluted water, entwining with each other to form a dense web that filters and absorbs large amounts of suspended matter. Through root absorption or adsorption, the plants physically capture, biochemically transform, and degrade pollutants, reducing nitrogen, phosphorus, and emerging pollutants such as phenol, microplastics, and fluoride in the water, turning them into nutrients for the plants. Radial oxygen secretion from the plant roots, combined with the action of bacteria in the riverbed, ultimately forms a biofilm on the plant root surfaces, effectively absorbing suspended matter and engulfing and metabolizing pollutants.

[0034] 2. The floating mat provided by the present invention is safe, stable and pollution-free;

[0035] The floating mat can provide buoyancy for plants, and has high stability, good durability, strong impact load resistance, no dissolution, low price, good hydrophobicity, easy to enrich biofilm, high porosity and permeability, and can effectively resist environmental degradation. On the other hand, the inorganic fillers suspended at the bottom of the floating mat have stable and strong adsorption function for pollutants in water, which are NH4 + -N and PO4 3- -P has strong adsorption properties; in the early stage, the physical adsorption and chemical precipitation of zeolite and sponge iron promoted the removal of nitrogen and phosphorus pollutants in the water; in the later stage, the inorganic filler can serve as an attachment carrier for microbial growth and enhance the contribution of biological action to pollutant removal, and can effectively remove pollutants even during the plant growth stagnation period in winter; the hanging inorganic filler also enhances the stability of the ecological floating blanket and the anti-lodging ability of plants.

[0036] 3. The planting matrix provided by the present invention promotes mutual promotion and efficiently absorbs pollutants;

[0037] Chitosan-potassium alginate-coated melamine-polyurethane composite foam possesses unique chemical and physical stability. It resists aging and decomposition in weakly acidic and alkaline environments, leaving no residual free formaldehyde. Its use in ecological floating blankets is both ecologically effective and environmentally friendly, with excellent adsorption properties for heavy metals and other pollutants. Alum sludge ceramsite, biochar, and scrap iron have high adsorption capacities for both inorganic and organic pollutants in water. Their combined use enhances the removal of chlorinated organics, nitroaromatic compounds, azo dyes, heavy metals, perchlorates, and nitrates from wastewater. Furthermore, alum sludge ceramsite and biochar provide more adhesion surface for microorganisms, enhancing their adsorption and degradation of pollutants in eutrophic water. The combined use of different planting substrates can significantly increase the rate of nitrogen and phosphorus removal from water bodies, while also promoting the richness, diversity, and uniformity of the microbial community and enhancing heterotrophic and autotrophic denitrification, which will benefit the further treatment of wastewater treatment plant effluent.

[0038] 4. The ecological floating blanket-fish-microorganism constructed by the present invention constitutes an ecological breeding technology. The tail water of the sewage treatment plant enters the river channel and is treated by the ecological floating blanket-fish-microorganism. In addition to reducing organic matter and nitrogen and phosphorus loads, it can also improve the ecology of the tail water, turning the sewage treatment plant tail water from "engineering water" into "ecological water". Fish leftover bait, excrement, etc. can provide nutrition for plants. The metabolism of the plants themselves can not only improve the water quality, but also the residual roots can be eaten by fish. Microorganisms, as intermediaries, can effectively regulate the microecological balance between fish and plants, and can promote the formation of a healthy food chain system in the receiving river channel, creating favorable conditions for a sustainable ecological health cycle. In addition to being used in rivers, the present invention can also be used in ponds, artificial wetlands and other environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings and the accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. Among them:

[0040] Figure 1 Schematic diagram of the structure of an embodiment of the present invention.

[0041] In the figure, 1-planting matrix, 2-inorganic filler. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present invention.

[0043] A river water ecological restoration method based on an ecological floating carpet, which uses an ecological floating carpet, fish, and microorganisms to construct an ecological restoration system to improve river water bodies, includes the following steps:

[0044] S1. River channel selection: The river channel is the receiving water body for the tailwater of the industrial wastewater treatment plant. A small fence facility is set up in the river channel. The upper edge of the fence is 1m above the water surface, and the bottom of the fence is compacted with gabions and penetrates into the bottom of the silt layer. The total area of ​​the test area separated by the small fence facility is about 5000m 2 , water flow speed does not exceed 1m / s;

[0045] S2. Preparation of ecological floating blanket: Figure 1 As shown, the ecological floating carpet includes plants, a carrier, a nylon net, a planting matrix 1 and an inorganic filler 2;

[0046] Plant selection: Plants should be selected based on the water quality characteristics of the river. Plants can reduce or fix nutrients and pollutants in the water through adsorption, absorption, accumulation and degradation. Plant roots become the most intense site of material circulation in the river, which has both economic and ecological benefits.

[0047] In the present invention, the plants in the ecological floating carpet are a combination of iris, windmill grass, water spinach, reed, and giant hyssop. The selected plants are domesticated through inoculation of pollutant-degrading bacteria and tolerance experiments.

[0048] Selection of floating mat: The floating mat has a certain buoyancy to ensure that the vegetation can float on the water surface. It has the characteristics of high stability, good durability, strong impact load resistance and no dissolution. The carrier used in this study has high porosity and permeability and can resist environmental degradation. At the same time, the lower part is suspended with an inorganic filler 2 that has a stable and strong adsorption function for pollutants in the water, and has a strong adsorption capacity for NH4 + -N and PO4 3- -P has strong adsorption properties; it can effectively remove pollutants even in the winter when plant growth is stagnant. The inorganic filler 2 hanging below also enhances the stability of the ecological floating blanket and the resistance of plants to lodging;

[0049] In the present invention, the carrier of the ecological floating blanket is a floating mat mainly made of EVA (ethylene-vinyl acetate copolymer material), with a thickness of 5 cm (the purchased EVA floating board is provided with holes for mounting the planting baskets); the area of ​​a single floating mat is 50 m 2 400 planting baskets were installed, and the floating mat covered 30% of the enclosure area. The planting baskets were installed on the floating mat to anchor the plant roots. A nylon mesh was used to suspend an inorganic filler 2, a combination of zeolite and sponge iron, from the bottom of the mat. The nylon mesh holding the inorganic filler 2 had been pre-treated to form a yellow-brown biofilm on its surface.

[0050] Selection of matrix materials: It plays a role in fixing plants and promoting biofilm attachment, while also having the advantages of providing nutrients, saving fertilizer, and adsorbing or degrading pollutants in water;

[0051] In the present invention, the planting matrix 1 is a combination of chitosan-potassium alginate coated melamine polyurethane composite foam, biochar, scrap iron, and alum sludge ceramsite;

[0052] S3. Selection of fish in the water: Fish with different purifying functions, including those that can ingest organic debris and phytoplankton, and have different habits and feeding characteristics, should be selected. The fish should be a combination of silver carp, bighead carp, and catfish, with a population ratio of 1:1:1. The fish to be released should weigh 0.3-0.5 kg each or be 4-6 cm long. The stocking density should be 9 fish / m2. 2 ; Selecting a variety of fish can effectively increase the transparency of water bodies, reduce the concentration of water pollutants, and thus help purify water bodies;

[0053] S4. Restoration of river water ecology: Six months after the ecological restoration system constructed by the ecological floating carpet, fish and microorganisms was put into use, the river water environment was improved, achieving harmonious and mutually beneficial symbiosis of plants, animals and microorganisms, and realizing material circulation and energy flow in the river ecosystem.

[0054] Traditional ecological floating blankets primarily consist of aquatic or terrestrial plants on the surface of water bodies. Through absorption and adsorption by plant roots and species competition, they reduce nitrogen, phosphorus, and organic matter in polluted water, thereby purifying water quality. However, they fail to remove emerging pollutants. In the present invention, the collaborative action of plant roots, microorganisms (including biofilm-forming microorganisms, rhizosphere microorganisms, and microorganisms attached to the planting substrate 1), and the planting substrate 1 significantly reduces emerging pollutants. The ecological floating blanket not only efficiently absorbs organic and inorganic pollutants in water but also provides energy for plants and microorganisms, promoting their degradation of emerging organic pollutants such as phenol, microplastics, and fluoride. The ecological floating blanket is highly stable and the plants are highly resistant to lodging, offering both ecological and economic benefits.

[0055] The plants in the ecological floating carpet of the present invention have the following characteristics:

[0056] 1) Iris: Iris has a certain tolerance and repair ability to organic pollutants. It has a good removal effect on nutrients such as total nitrogen, nitrite, and nitrate. At the same time, it can inhibit the reproduction and growth of algae by effectively controlling chlorophyll a in the water; it can also inhibit the increase in pH value of water bodies, reduce salinity, and increase transparency, which has a good effect on improving water quality.

[0057] 2) Windmill grass: With a well-developed root system and strong cold resistance, it has a strong ability to absorb and accumulate pollutants, promoting microbial biodegradation of pollutants and showing promising application prospects in wastewater treatment. Planting windmill grass helps improve the diversity and abundance of rhizosphere microorganisms, increasing the abundance of Acinetobacter, Pseudomonas, and Bacillus in the system, and promoting nitrogen and phosphorus removal.

[0058] 3) Water spinach: It is heat-resistant and waterlogged, has strong adaptability, a well-developed root system, and has a strong ability to purify water. There are many experimental research reports on its use to absorb nutrients and treat sewage or eutrophic water, and it also has certain economic benefits.

[0059] 3) Reed: It has well-developed rhizomes, strong adaptability, and fast reproduction speed. It has the advantages of deep water cold resistance, drought resistance, high temperature resistance, and lodging resistance. It can effectively remove total nitrogen and total phosphorus from water bodies, while inhibiting the growth of cyanobacteria, improving water purification functions, and avoiding eutrophication of water bodies. Its special root structure can not only enhance the adsorption capacity of pollutants, but also improve the living environment of various microorganisms and animals in the water; reed can also protect carbon storage and reduce the release of large amounts of carbon dioxide gas. It has multiple ecological functions such as regulating climate, inhibiting algae, and maintaining biodiversity.

[0060] 4) Large hyacinth: It grows fast and has a good removal effect on nitrogen and phosphorus in water bodies. It is also used for the remediation of metals in water bodies. It has a good removal effect on emerging pollutants such as fluoride in water, and can also be used as a fluoride pollution indicator.

[0061] The ecological restoration system constructed by the ecological floating carpet, fish, and microorganisms is maintained through regular replacement of inorganic fillers, planting substrates, and regular plant harvesting. Iris, windmill grass, and reeds are harvested every three months, while water spinach and giant hyacinth are harvested once a month.

[0062] Furthermore, the planting density of plants in the ecological floating carpet is 1kg seedlings / m 2 In this embodiment, the plant seedlings refer to healthy plant seedlings that have germinated for 5 days. The planting ratio of iris, windmill grass, water spinach, reed, and giant caltrop is 1.5:1.2:1.0:1.5:0.9. The plants in the ecological floating carpet can not only withstand the stress of pollutants and absorb pollutants in the water during their growth, but also provide attachment sites for microorganisms to grow through their developed plant root systems. In addition, plants also play a good role in beautifying the environment and providing habitats and food for aquatic animals and birds. Regular harvesting of plants can also serve as a planting matrix 1 to provide energy for a new batch of plants, further improving the purification efficiency of the ecological floating carpet.

[0063] Furthermore, the mass ratio of zeolite to sponge iron in the inorganic filler 2 is (0.8-1.2):1.

[0064] Furthermore, the plant acclimation experiment in step S2 includes the following steps:

[0065] (1) Bacillus velezensis 、 Three bacterial strains, Pseudomonas stutzeri and Bacillus cereus, were cultured in an inorganic salt medium containing 200 mg / L phenol for 24 h until the OD660 reached a value between 0.8 and 1.2. The culture medium was aspirated and centrifuged to harvest the cells, which were then resuspended in a 0.9% (w / v) NaCl solution. The optical density of each bacterial strain was adjusted to ensure that the cell count was no less than 1.0 × 10 7 CFU / mL, the three bacterial strain suspensions were mixed in a ratio of 1:1:1 to prepare 150 mL of inoculum;

[0066] (2) Prepare 20L of clean water, add a certain amount of rooting agent to the water to increase the survival rate of plants, and culture healthy plant seedlings that have germinated for 5 days in clean water for 20 days;

[0067] (3) The cultured plant seedlings were transferred to a contaminated water body with a phenol concentration of 300 mg / L. After sterilizing the contaminated water body and the surface of the plant roots, bacterial inoculum was added to the contaminated water body and the plant seedlings were cultured for 10 days.

[0068] Bacillus Velez 、 Pseudomonas stutzeri and Bacillus cereus are both plant growth-promoting bacteria. Adding them to water bodies can promote plant growth and improve plants' tolerance to pollutants and resistance to pathogens.

[0069] Bacillus Velez was purchased from the China Industrial Culture Collection Center (CICC) with the strain number CICC21120. Laboratory research showed that it can secrete a variety of bioactive substances and effectively inhibit a variety of plant pathogens. It is also a plant growth-promoting strain with high efficiency in nitrogen fixation, phosphorus solubilization, potassium solubilization, siderophore production and indoleacetic acid production, and can be used for water environment remediation.

[0070] Pseudomonas stutzeri was purchased from the China Industrial Culture Collection Center with the strain number CICC 10430. It is an activated sludge component strain with good growth-promoting and nitrous oxide emission reduction properties and can be used for sewage treatment.

[0071] Bacillus cereus was purchased from the China Industrial Culture Collection Center, with the strain number CICC 21290. It has a growth-promoting effect, can improve the quality of seedlings, promote root growth, increase yield and prevent diseases, enhance the crop's defense ability against adverse hazards such as pathogens, drought and low temperature freezing, and delay crop aging.

[0072] The five plants in the present invention have improved their tolerance to pollutants through laboratory acclimation experiments. When surviving in polluted water bodies, they can degrade and absorb pollutants, insoluble substances and heavy metals in the water bodies. The plant roots extend into the polluted water and entangle with each other in the water to form a dense net, filtering and absorbing a large amount of suspended matter in the water bodies. At the same time, through the absorption or adsorption of the plant roots, the pollutants are physically captured, biochemically transformed and degraded, reducing nitrogen, phosphorus and emerging pollutants such as phenol, microplastics, fluoride, etc. in the water bodies, making them nutrients for plants and promoting plant growth. During their growth, plants continuously release various organic compounds, such as organic acids, sugars, and vitamins, into their surroundings. These compounds provide a carbon source for microbial denitrification, thereby enhancing nitrogen removal. Furthermore, radial oxygen loss (ROL) from plant roots is a core element in the formation of the heterogeneous redox-redox microbial ecosystem within the rhizosphere. Its diffusion zone provides a favorable habitat for aerobic and anaerobic microorganisms, promoting their metabolic activity and fostering a favorable environment for nitrogen cycling and the growth of nitrifying, denitrifying, and anaerobic ammonium-oxidizing (ANAMMOX) bacteria. Oxygen consumption by aerobic and facultative bacteria within the rhizosphere may favor the growth of ANAMMOX bacteria, ultimately forming a biofilm on the plant root surface. Under the influence of extracellular polymeric substances, a microbial symbiosis, including bacteria, fungi, algae, protozoa, and metazoans, forms. Microorganisms within the root film not only produce polysaccharides that effectively adsorb suspended matter in the water but also phagocytose and metabolize pollutants, converting them into inorganic substances. The plant rhizosphere is the site of the most intense organic matter degradation, material recycling, and biological activity. Studies have shown that the strength of the ROL in plant roots is closely related to pollutant removal efficiency. On the other hand, biochar produced by harvesting plants from the ecological blanket can serve as a growing substrate for the ecological floating blanket. 1 Furthermore, the growth of these plants on the ecological blanket improves water clarity and dissolved oxygen levels, promotes the growth of microorganisms and aquatic animals, helps achieve ecological balance in river waters, and plays a significant role in beautifying the environment and providing a habitat for birds.

[0073] Furthermore, the nylon mesh pre-filming treatment process in step S2 is as follows:

[0074] (1) After soaking the nylon net in clean water for 30 hours, hang it in a container containing 50L of test water; the test water is the water taken from the river in step S1;

[0075] (2) A composite bacterial preparation was added to the test water body, aerated, and pre-filmed, waiting for the formation of a biofilm on the surface of the nylon mesh; the composite bacterial preparation was prepared by culturing and drying Bacillus subtilis, Bacillus lysinicola, and Microbacterium esters, and then mixing them in a ratio of 1:1:1, with an addition amount of 0.5 g / L.

[0076] Bacillus subtilis was purchased from the China Industrial Culture Collection Center, strain number CICC 0732. Bacillus subtilis is commonly used in wastewater treatment. Upon entering aquaculture water, it secretes a rich system of extracellular enzymes that rapidly degrade aquatic organic matter, such as excrement, leftover bait, plankton debris, and organic debris, converting them into nutrients required for the growth of unicellular algae, thus preventing the accumulation of organic waste in the water. This also effectively reduces oxygen consumption by organic matter in the water, indirectly increasing dissolved oxygen, ensuring the normal cycle of organic oxidation, ammoniation, nitrification, and denitrification, thereby maintaining good water quality.

[0077] Bacillus lysinin was purchased from the China Industrial Microbial Culture Collection Center, strain number CICC22093. Bacillus lysinin is used in environmental wastewater treatment research, effectively adsorbing heavy metals and degrading organic pollutants in water. This is particularly true in water bodies with severe eutrophication and frequent cyanobacterial blooms, where it can utilize the microcystins produced by these blooms as a carbon and nitrogen source for its growth and reproduction, thus possessing broad application prospects in water pollution control.

[0078] Microbacterium esters was purchased from the China Marine Microbial Culture Collection Center with the strain number 1F01189. After proliferating in water, it can use pesticides and organic pollutants containing benzene rings as carbon and nitrogen sources for growth, thereby playing a role in degrading pesticides and organic pollutants in water.

[0079] The material characteristics of the planting matrix 1 selected in the present invention are as follows:

[0080] 1) Chitosan-alginate-coated melamine polyurethane foam is a substrate for enhancing phosphate removal in ecological floating blankets. Chitosan is a natural biopolymer derived from chitin. The presence of reactive functional groups (such as amino and hydroxyl groups) enables chitosan to form hydrogen bonds with phosphate ions, thereby selectively adsorbing phosphate from wastewater. While removing phosphorus from water, the phosphorus adsorbed on the substrate with weaker binding affinity also facilitates efficient uptake by plant roots. Crosslinking chitosan with potassium alginate enhances the stability of chitosan as a phosphate adsorbent. This crosslinking process between the chitosan and alginate molecules creates a more rigid and insoluble structure. Furthermore, the formation of the crosslinked network increases the surface area and porosity of the chitosan-alginate hydrogel, providing more active sites for phosphate adsorption. While removing phosphorus from water, the phosphorus is adsorbed through weak hydrogen bonds and can be effectively utilized by plants. The unique chemical structure and three-dimensional crosslinking system of the melamine polyurethane foam impart unique chemical and physical stability. It resists aging and decomposition in weak acidic and alkaline environments, and leaves no residual free formaldehyde. The use of chitosan-potassium alginate coated melamine polyurethane foam in ecological floating carpet is ecologically effective and environmentally friendly.

[0081] The preparation steps of the chitosan-potassium alginate coating melamine polyurethane composite foam are as follows: 3 The melamine polyurethane foam was immersed in a chitosan-acetic acid solution and ultrasonicated for 30 minutes to obtain a first product; the first product was then immersed in a potassium alginate solution with a concentration of 1.0 g / L, allowed to stand at room temperature for 1 hour, and then taken out from the solution to obtain a second product; finally, the second product was immersed in a 6% calcium chloride solution for 30 hours and naturally dried to prepare a chitosan-potassium alginate coated melamine polyurethane composite foam.

[0082] The preparation process of chitosan-acetic acid solution is as follows: 10g chitosan is dissolved in 500mL of acetic acid solution with a mass concentration of 5%. After complete dissolution, the volume is adjusted to 1L with 5% acetic acid solution to obtain a chitosan-acetic acid solution with a mass concentration of 10g / L.

[0083] 2) Biochar is produced from sterilized plant material by pyrolysis at 500-600°C and stable carbonization for 2 hours. Specifically, plants on the ecological blanket are harvested regularly. Economically valuable plants, after testing and meeting national requirements, may be partially sold. The collected plants are then washed with sterile water and dried at 95°C for at least 36 hours. The plants are then cut and pulverized in a pulverizer. The pulverized plant material is then placed in a carbonization furnace for pyrolysis at 500-600°C and stable carbonization for 2 hours. After carbonization, the material is cooled to room temperature. Biochar can also be purchased directly from the market.

[0084] Biochar provides ample adsorption sites for the material itself to adsorb pollutants in the water. The excellent ion exchange capacity of its surface and the strong interaction between its diverse surface functional groups and pollutants promote this process, which directly reduces the concentration of pollutants in the water and reduces environmental risks. As a carbon source, biochar provides energy for plants, increases organic carbon in the water, inhibits the proliferation of algae, and provides essential nutrients for attached microorganisms to promote their growth, metabolism, and activity, thereby enhancing their ability to degrade and assimilate pollutants in the water. After microorganisms attach to its surface to form a biofilm, they can also directly adsorb particulate pollutants in the water. In addition, biochar can enhance denitrification in rivers by improving the diversity and composition of microbial communities.

[0085] 3) The scrap iron is in a spiral shape with a length of 2-3 cm. The addition of iron material mainly removes total phosphorus in water through the precipitation process between ferrous ions / ferric ions and phosphate. In addition, Fe 3+It reacts with water to form iron oxide (FeOOH, iron oxyhydroxide), which has a high adsorption capacity for phosphorus. Scrap iron, a byproduct, is more suitable for use in this invention than nano-iron due to its spiral shape, low cost, and reduced potential for clogging. The scrap iron used in this invention is purchased from surrounding factories, has a length of 8-23 cm, is spirally curved, and is cut before use. Testing has shown that the scrap iron is primarily composed of 95.8% iron, 3.24% carbon, and 0.96% other elements (such as Mn and Ti).

[0086] The combined use of biochar and iron filings simultaneously improved the removal rates of nitrate, total nitrogen and total phosphorus, while increasing the richness, diversity and uniformity of the microbial community, and increasing the abundance of nitrate-reducing bacteria and autotrophic denitrifying bacteria in the environment, which enhanced the denitrification process.

[0087] Preferably, the mass ratio of biochar to iron filings is 1:9. This ratio was obtained through a laboratory gradient experiment; this gradient experiment only studied the effects of biochar and iron filings on water pollutants. It was found that when 1 part biochar was added to 9 parts iron filings, the removal rates of nitrate, total nitrogen, and total phosphorus were simultaneously improved. It also increased the richness, diversity, and uniformity of the microbial community, and increased the abundance of Nitrospira and Sulfur Bacteria microorganisms.

[0088] The planting matrix 1 provided by the present invention promotes mutual promotion and efficient pollutant adsorption. Effectively utilizing both plant biochar and scrap iron byproducts can simultaneously increase nitrogen and phosphorus removal rates from contaminated water. The addition of iron improves the degradation of low-molecular-weight carbohydrates, while biochar promotes iron oxidation, increasing total phosphorus (TP) removal. The combined use of the two also enhances the richness, diversity, and uniformity of the microbial community and strengthens heterotrophic and autotrophic denitrification. Substances released by plant biomass promote iron oxidation, thereby increasing the rate of nitrogen and phosphorus removal from water.

[0089] 4) The raw material of the alum sludge ceramsite is taken from the alum sludge of the water plant; the alum sludge is kneaded into balls, air-dried at room temperature to constant weight, and then placed in a muffle furnace for 6 minutes at 600°C. After that, it is taken out and cooled at room temperature for 18 hours to produce the alum sludge ceramsite. The diameter of the alum sludge ceramsite is 0.5-0.6 cm, the average pore size is 3.5 mm, and the average specific surface area is 250 m 2Alum sludge is a byproduct of the water purification process in waterworks. After sedimentation, the sludge contains a large amount of active aluminum and aluminum ions, which have good phosphorus absorption properties and can effectively remove phosphorus from eutrophic water. Alum sludge ceramsite also provides more adhesion area for microorganisms, serving as a good carrier for microbial growth and plants. In short, the prepared alum sludge ceramsite enhances the adsorption capacity and microbial enrichment capacity of alum sludge. The microorganisms attached to its surface that are related to the degradation of organic pollutants in water can play a role in sewage treatment.

[0090] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with specific embodiments.

[0091] The experimental site in the following embodiments and comparative examples is Paihe River, one of the rivers flowing into Chaohu Lake from the west side. Paihe River is a heavily polluted river. The pollution entering the river is mainly industrial sewage and wastewater from Xiaomiao Town and Shangpai Town along the river, domestic sewage from the riverside communities, sewage treatment plants in the Economic Development Zone, and tail water from the sewage treatment plants in the Wildlife Park. In recent years, the main indicators of Paihe River have been in Class IV or Class V water standards all year round. The Paihe River is 67 km long with a drainage area of ​​586 square kilometers. There are 8 tributaries in Paihe River, and the drainage area of ​​each tributary is less than 100 square kilometers. Among them, the main tributaries on the right bank are Shuotou River, Wanglaoyan River, Nidayan River, etc.; the main tributaries on the left bank are Gunzi River, Yuexiao River, Banjiuyan River, Qixiao River, Gugang River, etc. The following embodiments and comparative examples are respectively set in the river channels of different tributaries. Although the water quality of different river channels is not completely consistent, the present invention mainly explores the removal efficiency of pollutants. The difference in pollutants in the water does not affect the comparability of the experimental results.

[0092] Example 1

[0093] A method for river water ecological restoration based on the use of an ecological floating blanket comprises the following steps:

[0094] S1. River channel selection: The river channel is the receiving water body for the tailwater of the industrial wastewater treatment plant. A small fence facility is set up in the river channel. The upper edge of the fence is 1m above the water surface, and the bottom of the fence is compacted with gabions and penetrates into the bottom of the silt layer. The total area of ​​the test area is about 5000m 2 , water flow speed does not exceed 1m / s;

[0095] S2. Preparation of ecological floating blanket: The ecological floating blanket includes plants, floating mats, carriers, nylon nets, planting substrates and inorganic fillers;

[0096] The plants in the ecological floating carpet are a combination of iris, windmill grass, water spinach, reed, and giant hyacinth, with a planting density of 1kg seedlings / m 2 The planting ratio of iris, windmill grass, water spinach, reed and big sedge is 1.5:1.2:1.0:1.5:0.9. The selected plants have been domesticated through inoculation of pollutant-degrading bacteria and tolerance experiments;

[0097] The carrier of the ecological floating blanket is a floating mat made mainly of EVA (ethylene-vinyl acetate copolymer material) with a thickness of 5cm. Planting baskets are installed on the floating mat to fix the roots of the plants. Inorganic fillers are suspended from the bottom of the floating mat through nylon mesh. The inorganic fillers are a combination of zeolite and sponge iron. The inorganic fillers have a stabilizing effect on the ecological floating mat and have a strong adsorption function for pollutants in the water. The mass ratio of zeolite to sponge iron in the inorganic fillers is 0.8:1. The nylon mesh containing the inorganic fillers is pre-filmed to form a layer of yellow-brown biofilm on its surface. The planting baskets are square, and each planting basket contains 50 chitosan-potassium alginate-coated melamine polyurethane composite foams (referred to as composite foams), 100g of biochar packed in a 2mm pore mesh bag, and 900g of iron filings as the planting matrix. The mesh bag is made of nylon.

[0098] Single floating pad area 50m 2 400 planting baskets are installed, and the total area of ​​the planting baskets accounts for 60% of the outer contour area of ​​the floating mat; four 500g inorganic fillers are hung under each floating mat, and the inorganic fillers are located 25cm below the water surface. The coverage area of ​​the ecological floating blanket accounts for 30% of the area of ​​the enclosure;

[0099] S3. Selection of fish in the water: The fish are a combination of catfish, silver carp and bighead carp, with the ratio of catfish, silver carp and bighead carp being 1:1:1, and the density of fish stocking is 9 fish / m 2 ;

[0100] S4. Restoration of river water ecology: Six months after the ecological restoration system constructed by the ecological floating carpet, fish and microorganisms was put into use, the river water environment was improved, achieving harmonious and mutually beneficial symbiosis of plants, animals and microorganisms, and realizing material circulation and energy flow in the river ecosystem.

[0101] Example 2

[0102] The difference between Example 2 and Example 1 is that:

[0103] (1) The mass ratio of zeolite to sponge iron in the inorganic filler is 1:1;

[0104] (2) Fifty chitosan-potassium alginate-coated melamine polyurethane composite foams and 1000 g alum sludge ceramsite were placed in each of the planting baskets as planting substrates.

[0105] Example 3

[0106] The only difference between Example 3 and Example 1 is that:

[0107] (1) The mass ratio of zeolite to sponge iron in the inorganic filler is 1.2:1;

[0108] (2) 500 g of alum sludge ceramsite, 50 g of biochar in a mesh bag, and 450 g of iron filings were placed in each planting basket as a planting medium.

[0109] Example 4

[0110] The only difference between Example 4 and Example 1 is that:

[0111] (1) The mass ratio of zeolite to sponge iron in the inorganic filler is 1:1;

[0112] (2) In each of the planting baskets, 50 chitosan-potassium alginate coated melamine polyurethane composite foams, 50 g of biochar and 450 g of iron filings in a mesh bag, and 500 g of alum sludge ceramsite were placed as planting substrates.

[0113] Comparative Example 1

[0114] The only difference between Comparative Example 1 and Example 1 is that no inorganic filler is added.

[0115] Comparative Example 2

[0116] The only difference between Comparative Example 2 and Example 1 is that 1000 g of vermiculite was placed in each planting basket as a conventional planting medium for comparison. The vermiculite had a size of 2-4 mm and was purchased from Hebei Chuangjuman Mineral Products Co., Ltd.

[0117] Experimental data and analysis

[0118] After 6 months of treatment with the examples and comparative examples, an appropriate amount of water was taken from the river and the water quality was measured in the laboratory to test the improvement effect of the ecological floating blankets of Examples 1-4 on the river water environment. The test results are recorded in Table 1, where the unit in Table 1 is %.

[0119] Table 1 Experimental data of ecological floating blankets for improving river water environment in Examples 1-4

[0120]

[0121] From the data in Table 1, we can see that:

[0122] 1. The results of Examples 1-4 demonstrate that the ecological floating blankets of the present invention are significantly effective in degrading and adsorbing pollutants, and promoting the growth and reproduction of microorganisms and plants. On the one hand, the ecological floating blankets can degrade and adsorb pollutants in water, improving water quality and reducing the toxic effects of pollutants on plants and microorganisms, thereby promoting their growth and reproduction. On the other hand, the ecological floating blankets provide a substrate for microorganisms to attach and grow, while also anchoring plants and providing them with absorbable nutrients. Furthermore, the ecological floating blankets inhibit algae growth, effectively preventing eutrophication while providing habitats for aquatic animals and birds, thereby enhancing the stability of river ecosystems.

[0123] 2. The results of Examples 1-4 demonstrate that the synergistic interaction between the plants, carrier, and substrate of this application can achieve a better improvement in the river water environment. Reducing the amount and amount of substrate used, or changing the substrate type, can adversely affect the improvement of the river water ecological environment. A comprehensive comparison of Examples 1-4 shows that Example 4 is the best example of this invention.

[0124] 3. The overall fluoride removal rate in the test results was relatively low. This is because the commonly used treatment methods for fluoride-containing wastewater currently include precipitation and adsorption. Research on fluoride removal in sewage treatment plants has shown that fluoride removal relies primarily on adsorption by activated sludge, with microorganisms having little effect on fluoride purification. Furthermore, the assimilation and utilization efficiency of fluoride by most aquatic plants and animals is also low. In this test, fluoride removal primarily relied on chemical adsorption by the planting substrate and absorption by the plant's phytoplankton, resulting in a relatively low overall removal rate.

[0125] 4. Comparing Example 1 with Comparative Example 1, by comparing the removal results of various indicators with and without inorganic fillers, it was found that the removal rates of various items decreased, indicating that inorganic fillers have removal effects on traditional organic pollutants and emerging pollutants, but overall, planting matrix, microorganisms and plants play a major role in the removal of pollutants.

[0126] 5. Comparing Example 1 with Comparative Example 2, the planting matrix was replaced with vermiculite. It can be seen that the removal rates of various items have dropped significantly, indicating that the planting matrix (composite foam, biochar and iron filings) not only has a removal effect on traditional pollutants such as total nitrogen and total phosphorus, but also has a certain removal effect on phenol, fluoride and microplastics.

[0127] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A river water ecological restoration method based on ecological floating carpet, characterized in that: The ecological restoration system using ecological floating carpets, fish, and microorganisms to improve river water quality includes the following steps: S1. River channel selection: The river channel is the receiving water body for the tailwater of the industrial wastewater treatment plant. A small fence facility is used to isolate the treatment area in the river channel. The water flow velocity in the treatment area does not exceed 1m / s. S2. Preparation of Ecological Floating Blankets: The ecological floating blankets include plants, carriers, nylon mesh, planting substrates, and inorganic fillers. The plants in the ecological floating blankets are a combination of irises, windmill grass, water spinach, reeds, and giant hyacinths. The selected plants have been inoculated with pollutant-degrading bacteria and acclimated through tolerance experiments. The carrier of the ecological floating carpet is a floating mat made of EVA, on which a planting basket is installed to fix the roots of the plants. The inorganic filler is suspended from the bottom of the floating mat through a nylon mesh. The inorganic filler is a combination of zeolite and sponge iron. The nylon mesh containing the inorganic filler is pre-coated with a composite bacterial preparation, forming a yellow-brown biofilm on its surface. The composite bacterial preparation is made by culturing and drying Bacillus subtilis, Bacillus lysinicus, and Microbacterium esters, and then mixing them in a 1:1:1 ratio. The planting matrix is ​​a combination of chitosan-potassium alginate-coated melamine polyurethane composite foam, biochar, scrap iron, and alum sludge ceramsite. S3. Selection of fish in the water: Fish with different purifying functions, such as those that can ingest organic debris and phytoplankton, and have different habits and feeding characteristics, should be selected from a combination of silver carp, bighead carp, and catfish. S4. Restoration of river water ecology: Six months after the ecological restoration system constructed by the ecological floating carpet, fish, and microorganisms was put into operation, the river water environment has improved; The plant acclimation experiment in step S2 includes the following steps: (1) Bacillus velezensis, Pseudomonas stutzeri, and Bacillus cereus were cultured in an inorganic salt medium containing 200 mg / L phenol for 24 h until OD 660 The optical density of each bacterial strain was adjusted to a value between 0.8 and 1.

2. The cells were harvested by centrifugation and then resuspended in 0.9% (w / v) NaCl solution. The optical density of each bacterial strain was adjusted to a cell number of not less than 1.0 × 10 7 CFU / mL, the three bacterial strain suspensions were mixed in a ratio of 1:1:1 to prepare 150 mL of inoculum; (2) Prepare 20L of clean water, add a certain amount of rooting agent to the water to increase the survival rate of plants, and culture healthy plant seedlings in the clean water for 20 days; (3) The cultured plant seedlings were transferred to a contaminated water body with a phenol concentration of 300 mg / L. After sterilizing the contaminated water body and the surface of the plant roots, 150 ml of bacterial inoculum was added to the contaminated water body and the plant seedlings were cultured for 10 days.

2. The river water ecological restoration method based on ecological floating carpet according to claim 1 is characterized by: The planting density of plants in the ecological floating carpet is 1kg seedlings / m 2 The planting ratio of iris, windmill grass, water spinach, reed and giant caltrop is (1.4-1.6): (1.1-1.3): (0.9-1.1): (1.4-1.6): (0.9-1.0); the number ratio of catfish, silver carp and bighead carp is 1:1:1, the weight of fish released is 0.3-0.5 kg / fish, and the stocking density is 9 fish / m 2 .

3. The river water ecological restoration method based on ecological floating carpet according to claim 1 is characterized in that: The mass ratio of zeolite to sponge iron in the inorganic filler is (0.8-1.2):

1.

4. The river water ecological restoration method based on ecological floating carpet according to claim 1 is characterized in that: The nylon mesh pre-filming treatment process in step S2 is as follows: (1) After soaking the nylon net in clean water for 30 hours, hang it in a container containing 50L of test water; the test water is the water taken from the river in step S1; (2) Add the composite bacterial preparation to the test water, aerate it, and pre-film it, waiting for the formation of biofilm on the surface of the nylon mesh; the addition amount of the composite bacterial preparation is 0.5 g / L.

5. The river water ecological restoration method based on ecological floating carpet according to claim 1 is characterized in that: The preparation steps of the chitosan-potassium alginate coating melamine polyurethane composite foam are as follows: 3 The melamine polyurethane foam was immersed in a chitosan-acetic acid solution and ultrasonicated for 30 minutes to obtain a first product; the first product was then immersed in a 1.0 g / L potassium alginate solution, allowed to stand at room temperature for 1 hour, and then removed from the solution to obtain a second product; finally, the second product was immersed in a 6% calcium chloride solution for 30 hours and naturally dried to produce a chitosan-potassium alginate coated melamine polyurethane composite foam; The biochar is made by pyrolysis of sterilized plant raw materials at 500-600°C and stable carbonization for 2 hours; The scrap iron is in a spiral shape and has a length of 2-3 cm; The raw material of the alum sludge ceramsite is taken from the alum sludge of the water plant; the alum sludge is kneaded into a ball, air-dried to constant weight at room temperature, placed in a muffle furnace at 600°C for 6 minutes, taken out, and cooled at room temperature for 18 hours to prepare the alum sludge ceramsite. The diameter of the ceramsite is 0.5-0.6 cm, the average pore size is 3.5 mm, and the average specific surface area is 250 m 2 / g.

6. The river water ecological restoration method based on ecological floating carpet according to claim 1 is characterized by: 50 chitosan-potassium alginate coated melamine polyurethane composite foams, 100 g of biochar in a mesh bag and 900 g of iron filings were placed in each planting basket.

7. The river water ecological restoration method based on ecological floating carpet according to claim 1 is characterized by: 50 chitosan-potassium alginate coated melamine polyurethane composite foams and 1000 g alum sludge ceramsite were placed in each of the planting baskets.

8. The river water ecological restoration method based on ecological floating carpet according to claim 1 is characterized by: 500 g of alum sludge ceramsite, 50 g of biochar filled in a mesh bag and 450 g of iron filings were placed in each planting basket.

9. The river water ecological restoration method based on ecological floating carpet according to claim 1 is characterized by: 50 chitosan-potassium alginate coated melamine polyurethane composite foams, 50 g of biochar and 450 g of iron filings, and 500 g of alum sludge ceramsite contained in a mesh bag were placed in each of the planting baskets.

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