River water ecological restoration method based on ecological floating blanket

Abstract

The invention belongs to the field of water ecological restoration, and particularly relates to a riverway water ecological restoration method based on an ecological floating blanket, ecological floating blanket-fish-microorganism is utilized to construct an ecological restoration system to improve a riverway water body, and the ecological floating blanket comprises plants, a carrier, a nylon net, a planting matrix and an inorganic filler; the selected plants are subjected to pollutant degrading bacterium inoculation and tolerance experiment domestication; inorganic filler is hung on the lower part of the ecological floating blanket through a nylon net; the nylon net is subjected to membrane pre-hanging treatment, so that a layer of yellowish-brown biological membrane is formed on the surface of the nylon net; the planting substrate is a combination of multiple of chitosan-potassium alginate coating melamine polyurethane composite foam, biochar, scrap iron and alum sludge ceramsite; the plant provided by the invention is high in tolerance and can efficiently adsorb and degrade pollutants; the planting matrix provided by the invention promotes each other and efficiently adsorbs pollutants; the constructed ecological floating blanket-fish-microorganism ecological planting and breeding technology can promote a receiving river channel to form a food chain system with a healthy water body.

Description

Technical Field

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

[0002] Wastewater discharge from industrial parks has the characteristics of industry characteristics, large fluctuations in water quality and quantity, high COD concentration, and complex composition. 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" after engineering means, adding chemical agents, etc., in which the organic pollutants discharged are difficult to degrade in the environment, affecting the stability of the ecological environment, and will be enriched in aquatic organisms, causing poisoning to them. The tail water of industrial park wastewater after being treated 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, and discharge into natural water bodies is not conducive to the quality of the surface water environment.

[0003] This type of tailwater contains emerging pollutants such as phenol and its derivatives, microplastics, and perfluoroalkyl and polyfluoroalkyl substances (PFAS). Among them, phenol and its derivatives are aromatic compounds, which are protoplasmic poisons that are toxic to organisms and difficult to degrade. They are common pollutants in industrial wastewater. Everyday plastics are exposed to weathering, sunlight and wear for a long time, breaking down into smaller fragments. Plastics smaller than 5 mm are classified as microplastics. Microplastics enter the sewage treatment plant with sewage, and unremoved microplastics are discharged into local rivers with the tailwater of the sewage treatment plant. Although primary wastewater treatment can remove larger particles, due to the lack of a special removal process, this defect has caused sewage treatment plants to become an important source of microplastic pollution. PFAS is widely used in various industries. Due to its extremely high thermal and chemical stability, PFAS persists in the environment. PFAS enters the water environment in various ways. It can not only be directly discharged through industrial sewage and domestic sewage, but also enter the water body through indirect pathways such as landfill leachate and dust, and finally converge into the sewage treatment plant. Although traditional sewage treatment processes can remove a certain amount of PFAS, there are still PFAS residues in the tailwater. The tertiary treatment processes of chlorination, ozone oxidation, and ultraviolet disinfection are also unable to effectively remove PFAS and have negative removal effects.

[0004] Ecological floating blanket is a new water remediation technology developed from traditional artificial wetlands. Due to its advantages of low investment, high efficiency, no need for additional land, strong adaptability to water depth, flexible operation, simple maintenance, and green economy, it is becoming more and more popular and widely used in landscape water remediation projects. In the ecological floating blanket system, the upper part is vigorous plants, and the lower part is a developed plant root system with rich biofilm attached to it. The carrier in the ecological floating blanket system can provide buoyancy for the plants, and the medium plays a role in fixing the plants. Under the joint action of plant absorption, microbial assimilation and transformation, adsorption and precipitation and other mechanisms, the ecological floating blanket can purify the water system. At present, ecological floating blankets have many applications in the purification of landscape water and traditional pollutants, but there are no reports on the purification effect of the above-mentioned emerging pollutants.

[0005] Therefore, it is necessary to provide an improved technical solution to address 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: A river water ecological restoration method based on an ecological floating blanket, which uses an ecological floating blanket-fish-microorganism to construct an ecological restoration system to improve the river water body, includes the following steps: S1. River channel selection: The river channel is the receiving water body for the tailwater of the industrial sewage 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 blanket: The ecological floating blanket includes plants, carriers, nylon nets, planting substrates and inorganic fillers; the plants in the ecological floating blanket are a combination of irises, windmill grass, water spinach, reeds and giant hyacinth, and the selected plants are inoculated with pollutant-degrading bacteria and domesticated through tolerance experiments; 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 plants. The inorganic filler is suspended through a nylon net at the bottom of the floating mat. The inorganic filler is a combination of zeolite and sponge iron. The nylon net containing 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. S3. Selection of fish in the water: fish purification functional groups are fish that can ingest organic debris and floating algae and have different habits and feeding characteristics; fish are a combination of silver carp, bighead carp and bighead carp; S4. Restoration of river water ecology: Six months after the ecological restoration system constructed by ecological floating carpet-fish-microorganisms was put into use, the river water environment was improved.

[0008] Furthermore, the planting density of plants in the ecological floating carpet is 1 kg seedlings / m 2 The planting ratio of iris, windmill grass, water spinach, reed and bighead carp 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 0.3-0.5kg / fish, and the release density is 9 / m 2 .

[0009] Furthermore, the mass ratio of zeolite to sponge iron in the inorganic filler is (0.8-1.2):1.

[0010] Furthermore, the plant acclimatization 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 be between 0.8 and 1.2. The culture medium was centrifuged to harvest the cells, and then resuspended in 0.9% (w / v) NaCl solution. The optical density of each bacterial strain was adjusted so that the cell number was 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 20 L 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 contaminated water with a phenol concentration of 300 mg / L. After sterilizing the contaminated water and the surface of the plant roots, 150 ml of bacterial inoculum was added to the contaminated water and the plant seedlings were cultured for 10 days.

[0011] Furthermore, the nylon mesh pre-film treatment process in step S2 is as follows: (1) After soaking the nylon net in clean water for 30 h, hang it in a container containing 50 L of test water; the test water is the water taken from the river in step S1; (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.

[0012] Furthermore, the preparation steps of the chitosan-potassium alginate coated melamine polyurethane composite foam are as follows: 3The melamine polyurethane foam was immersed in a chitosan-acetic acid solution and subjected to ultrasound for 30 min to obtain a first product; the first product was then immersed in a potassium alginate solution with a concentration of 1.0 g / L, and was taken out from the solution after standing at room temperature for 1 h to obtain a second product; finally, the second product was immersed in a 6% calcium chloride solution for 30 h and naturally dried to obtain a chitosan-potassium alginate coated melamine polyurethane composite foam; The biochar is made from sterilized plant raw materials by pyrolysis at 500-600°C and stable carbonization for 2 hours; The scrap iron is in a spiral shape with 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 at room temperature to constant weight, 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.

[0013] In one embodiment, 50 chitosan-potassium alginate coated melamine polyurethane composite foams, 100 g of biochar contained in a mesh bag and 900 g of iron filings are placed in each of the planting baskets.

[0014] 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.

[0015] 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.

[0016] 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 filled in a mesh bag are placed in each of the planting baskets.

[0017] The beneficial effects of the present invention are: 1. The plants provided by the present invention have strong tolerance and can efficiently adsorb and degrade pollutants; Through laboratory domestication experiments, the five plants have improved their tolerance to pollutants. When living in polluted water, they can degrade and absorb pollutants, insoluble substances and heavy metals in the water. The plant roots extend deeply into the polluted water, entangled with each other in the water to form a dense network, filtering and absorbing a large amount of suspended matter in the water. Through the absorption or adsorption of the plant roots, they are used for the physical capture, biochemical transformation and degradation of pollutants, reducing nitrogen, phosphorus, phenol, microplastics, fluoride and other emerging pollutants in the water, making them nutrients for plants. The combined action of radial oxygen secretion of plant roots and bacteria in the river will eventually form a biofilm on the surface of the plant roots, effectively absorbing suspended matter in the water, and engulfing and metabolizing pollutants in the water.

[0018] 2. The floating pad provided by the present invention is safe, stable and pollution-free; The floating mat can provide buoyancy for plants, 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 the water. They are very effective for 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 in the winter when plant growth is stagnant; the hanging inorganic filler also enhances the stability of the ecological floating blanket and the resistance of plants to lodging.

[0019] 3. The planting matrix provided by the present invention promotes each other and efficiently absorbs pollutants; Chitosan-potassium alginate coated melamine polyurethane composite foam has unique chemical and physical stability. It will not age or decompose in weak acid and weak alkali environments, and there is no residual free formaldehyde. Its use in ecological floating blankets is ecologically effective and environmentally friendly, and it has good adsorption properties for pollutants such as heavy metals in the environment. Alum sludge ceramsite, biochar and scrap iron have high adsorption capacity for inorganic and organic pollutants in water. Mixed use can enhance the removal effect of chlorinated organic matter, nitro aromatic compounds, azo dyes, heavy metals, perchlorates, nitrates, etc. in sewage. At the same time, alum sludge ceramsite and biochar can also provide more adhesion area 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 denitrification and phosphorus removal in water bodies, while being beneficial to the richness, diversity and uniformity of microbial communities, and enhancing heterotrophic or autotrophic denitrification, which will be beneficial to the further treatment of tail water from sewage treatment plants.

[0020] 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. After being 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, so that the tail water of the sewage treatment plant is transformed from "engineering water" to "ecological water". The fish leftover bait, excrement, etc. can provide nutrition for plants, and the metabolism of the plants themselves can improve the water quality, and 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, forming 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

[0021] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them: Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0022] In the figure, 1-planting matrix, 2-inorganic filler. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0024] A river water ecological restoration method based on an ecological floating blanket, which uses an ecological floating blanket-fish-microorganism to construct an ecological restoration system to improve the river water body, includes the following steps: S1. River channel selection: The river channel is the receiving water body for the tailwater of the industrial sewage treatment plant. A small fence facility is set up in the river channel. The upper edge of the fence is 1 m 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 5000 m 2 , water flow speed does not exceed 1m / s; S2. Preparation of ecological floating blanket: Figure 1 As shown, the ecological floating blanket includes plants, a carrier, a nylon net, a planting matrix 1 and an inorganic filler 2; Plant selection: Plants to be planted are selected according to 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 place for material circulation in the river, with both economic and ecological effects. In the present invention, the plants in the ecological floating blanket are a combination of irises, windmill grass, water spinach, reeds, and giant hyacinth, and the selected plants are domesticated through inoculation of pollutant-degrading bacteria and tolerance experiments; 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 performance; even in the winter when plant growth is stagnant, it can effectively remove pollutants. The inorganic filler 2 hanging below also enhances the stability of the ecological floating blanket and the lodging resistance of plants; In the present invention, the carrier in the ecological floating blanket is a floating pad mainly made of EVA (ethylene-vinyl acetate copolymer material) with a thickness of 5 cm (the purchased EVA floating board is provided with basket holes adapted to the planting basket); the area of ​​a single floating pad is 50 m 2 , 400 planting baskets were installed, and the floating blanket covered an area of ​​30% of the enclosure area. Planting baskets were installed on the floating mat to fix the roots of the plants. The inorganic filler 2 was suspended through a nylon net at the bottom of the floating mat. The inorganic filler 2 was a combination of zeolite and sponge iron. The nylon net holding the inorganic filler 2 was pre-filmed to form a layer of yellow-brown biofilm on its surface. Selection of matrix materials: It plays a role in fixing plants and promoting biofilm attachment, and also has the advantages of providing nutrients, saving fertilizer, and absorbing or degrading pollutants in water; In the present invention, the planting matrix 1 is a combination of multiple types of chitosan-potassium alginate coated melamine polyurethane composite foam, biochar, scrap iron, and alum sludge ceramsite; S3. Selection of fish in the water: The fish purification functional group is a group of fish that can ingest organic debris and floating algae and have different habits and feeding characteristics; the fish are a combination of silver carp, bighead carp and catfish, with the number ratio of silver carp, bighead carp and catfish being 1:1:1, the fish released is 0.3-0.5kg / tail or 4-6cm long per tail, and the density of fish released is 9 / m 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; S4. Restoration of river water ecology: Six months after the ecological restoration system constructed by ecological floating carpet-fish-microorganism was put into use, the river water environment was improved, achieving harmonious and mutually beneficial symbiosis of plants-animals-microorganisms, and realizing material circulation and energy flow in the river ecosystem.

[0025] Traditional ecological floating blankets are mainly composed of aquatic plants or terrestrial plants on the surface of water bodies. Through the absorption, adsorption and species competition of plant roots, nitrogen, phosphorus and organic matter in polluted water bodies are reduced, thereby achieving the effect of purifying water quality, but the effect of removing emerging pollutants cannot be achieved. In the present invention, the emerging pollutants are significantly reduced under the joint cooperation of plant roots, microorganisms (including biofilm microorganisms, rhizosphere microorganisms and microorganisms attached to the planting matrix 1) and the planting matrix 1. In the present invention, the ecological floating blanket can efficiently absorb organic and inorganic pollutants in water and provide energy for plants and microorganisms, promoting their degradation of emerging organic pollutants such as phenol, microplastics and fluoride in water bodies. The ecological floating blanket has high stability and strong lodging resistance of plants, and has both ecological and economic benefits.

[0026] The plants in the ecological floating carpet of the present invention have the following characteristics: 1) Iris: Iris has a certain tolerance and repair ability to organic pollutants, and 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 of pH value of water bodies, reduce salinity, and increase transparency, which has a good effect on improving water quality.

[0027] 2) Windmill grass: With a well-developed root system and strong cold resistance, it has a strong ability to absorb and enrich pollutants, can promote the biodegradation of pollutants by microorganisms, and has good application prospects in sewage treatment. Planting windmill grass helps improve the diversity and abundance of rhizosphere microorganisms, increases the abundance of Acinetobacter, Pseudomonas, and Bacillus in the system, and is conducive to nitrogen and phosphorus removal.

[0028] 3) Water spinach: It is heat-resistant and waterlogging-resistant, 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.

[0029] 3) Reed: It has well-developed rhizomes, strong adaptability, and fast reproduction speed. It has the advantages of deep water resistance, drought resistance, high temperature resistance, and lodging resistance. It can effectively remove total nitrogen and total phosphorus in 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.

[0030] 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.

[0031] The ecological restoration system constructed by the ecological floating carpet-fish-microorganism is maintained by regularly replacing inorganic fillers 2, planting substrates 1, and regularly harvesting plants. Among them, irises, windmill grass, and reeds are harvested once every three months, and water spinach and giant hyacinth are harvested once a month.

[0032] Furthermore, the planting density of plants in the ecological floating carpet is 1 kg 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 big sedge 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 growth, but also provide attachment sites for microorganisms to grow through 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 be used as a planting matrix 1 to provide energy for a new batch of plants, further improving the purification efficiency of the ecological floating carpet.

[0033] Furthermore, the mass ratio of zeolite to sponge iron in the inorganic filler 2 is (0.8-1.2):1.

[0034] Furthermore, the plant acclimatization 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 the OD660 was between 0.8 and 1.2. The culture medium was centrifuged to harvest the cells, and then resuspended in a 0.9% (w / v) NaCl solution. The optical density of each bacterial strain was adjusted so that the cell number was not less than 1.0×107 CFU / mL, and the suspensions of the three bacterial strains were mixed in a ratio of 1:1:1 to prepare 150 mL of inoculum. (2) Prepare 20 L 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; (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.

[0035] Bacillus Velez 、 Pseudomonas stutzeri and Bacillus cereus are both plant growth-promoting bacteria. Adding them to water bodies can promote plant growth and increase plants' tolerance to pollutants and resistance to pathogens.

[0036] Bacillus Velez was purchased from the China Industrial Culture Collection Center (CICC) with the strain number CICC21120. Laboratory research found that it can secrete a variety of biologically active substances and effectively inhibit a variety of plant pathogens. It is also a plant growth-promoting strain that is efficient in nitrogen fixation, phosphorus solubilization, potassium solubilization, iron carrier production and indoleacetic acid production, and can be used for water environment remediation.

[0037] Pseudomonas stutzeri was purchased from the China Industrial Microbiological Culture Collection Center with the strain number CICC 10430. It is an activated sludge constituent strain with good growth-promoting and nitrous oxide emission reduction properties and can be used for sewage treatment.

[0038] Bacillus cereus was purchased from the China Industrial Microbiology 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 defense ability of crops against adverse hazards such as pathogens, drought and low temperature freezing, and delay crop aging.

[0039] The five plants in the present invention improve 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, which filters and absorbs a large amount of suspended matter in the water bodies. At the same time, through the absorption or adsorption of the plant root system, the pollutants are physically captured, biochemically transformed and degraded, and nitrogen, phosphorus, phenol, microplastics, fluoride and other emerging pollutants in the water bodies are reduced, making them nutrients for plants and promoting plant growth. During their growth, plants continuously release various organic acids, sugars, vitamins and other organic substances to the surrounding environment, which can provide carbon sources for microbial denitrification and thus enhance nitrogen removal. In addition, radial oxygen loss (ROL) of plant roots is the core element of the rhizosphere oxidation-reduction heterogeneous micro-ecosystem. Its diffusion layer provides a good habitat for aerobic and anaerobic microorganisms and promotes their metabolic activities, providing a suitable environment for the nitrogen cycle process and nitrifying bacteria, denitrifying bacteria and anaerobic ammonia-oxidizing bacteria. The consumption of oxygen by aerobic or facultative bacteria in the rhizosphere of plants may be conducive to the growth of anaerobic ammonia-oxidizing bacteria, and eventually gradually forms a biofilm on the surface of plant roots, and forms a microbial symbiosis including bacteria, fungi, algae, protozoa and metazoa under the action of extracellular polymers. The microorganisms in the root membrane not only produce polysaccharides, which effectively adsorb suspended matter in water, but also engulf and metabolize pollutants in water and convert them into inorganic matter. The plant rhizosphere has become the most intense place for organic matter degradation, material circulation and life activities. Existing results have proved that the strength of plant root ROL is closely related to the removal effect of pollutants. On the other hand, the biochar produced by harvesting the plants on the ecological blanket can be used as the planting matrix of the ecological floating blanket. In addition, the growth of these plants on the ecological blanket can improve the transparency and dissolved oxygen content of the water body, promote the growth of microorganisms and aquatic animals, help the river water body achieve water ecological balance, and also play a good role in beautifying the environment and providing a habitat for birds.

[0040] Furthermore, the nylon mesh pre-film treatment process in step S2 is as follows: (1) After soaking the nylon net in clean water for 30 h, hang it in a container containing 50 L of test water; the test water is the water taken from the river in step S1; (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 lysine, and Microbacterium esters, and then mixing them in a ratio of 1:1:1, with an addition amount of 0.5 g / L.

[0041] Bacillus subtilis was purchased from the China Industrial Microbial Culture Collection Management Center, and the strain number is CICC 0732. Bacillus subtilis is commonly used in sewage treatment. After entering the aquaculture water body, it can secrete a rich extracellular enzyme system to promptly degrade organic matter in the water body, such as excrement, leftover bait, plankton residues and organic debris, so that it can be mineralized into nutrients required for the growth of unicellular algae, thereby avoiding the accumulation of organic waste in the water. At the same time, it effectively reduces the oxygen consumption of organic matter in the water, indirectly increases the dissolved oxygen in the water, and ensures the normal cycle of organic matter oxidation, ammoniation, nitrification and denitrification, thereby maintaining good water quality.

[0042] Lysinibacillus was purchased from the China Industrial Microbial Culture Collection Center, with the strain number CICC22093. Lysinibacillus is used in environmental sewage treatment research and can effectively adsorb heavy metals in water and degrade organic pollutants in water. Especially in water bodies with serious eutrophication problems and frequent outbreaks of cyanobacteria blooms, it can use microcystins produced by cyanobacteria bloom pollution as a carbon source and nitrogen source for its own growth and reproduction, and has broad application prospects in water pollution control.

[0043] 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.

[0044] The material characteristics of the planting matrix 1 selected in the present invention are as follows: 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 phosphates from wastewater. While removing phosphorus from the water body, phosphorus adsorbed on substrates with weaker binding affinity also contributes to the effective absorption by plant roots. Crosslinking chitosan with potassium alginate can enhance the stability of chitosan as a phosphate adsorbent. This crosslinking process between chitosan and alginate molecules produces a harder and insoluble structure. In addition, the formation of a crosslinked network increases the surface area and porosity of chitosan-alginate hydrogels, providing more active sites for phosphate adsorption. While removing phosphorus from the water body, phosphorus is adsorbed by forming weak hydrogen bonds and can be effectively used by plants. The specific chemical structure and three-dimensional network crosslinking system of melamine polyurethane foam give it unique chemical and physical stability. It will not age or decompose in weak acid and weak alkaline environments, and there is no residual free formaldehyde. The use of chitosan-potassium alginate coated melamine polyurethane foam in ecological floating carpet is ecologically effective and environmentally friendly.

[0045] The preparation steps of the chitosan-potassium alginate coated melamine polyurethane composite foam are as follows: 3 The melamine polyurethane foam was immersed in a chitosan-acetic acid solution and ultrasonicated for 30 min to obtain the first product; then the first product was immersed in a potassium alginate solution with a concentration of 1.0 g / L, and was taken out from the solution after standing at room temperature for 1 h to obtain the second product; finally, the second product was immersed in a 6% calcium chloride solution for 30 h and naturally dried to prepare a chitosan-potassium alginate coated melamine polyurethane composite foam.

[0046] The preparation process of chitosan-acetic acid solution is as follows: 10 g of chitosan is dissolved in 500 mL of acetic acid solution with a mass concentration of 5%. After complete dissolution, the volume is fixed to 1 L with 5% acetic acid solution to obtain a chitosan-acetic acid solution with a mass concentration of 10 g / L.

[0047] 2) The biochar is made from sterilized plant materials by high-temperature pyrolysis at 500-600℃ and stable carbonization for 2 hours; specifically, plants on the ecological blanket are harvested regularly, and plants with economic value can be partially sold after testing and meeting national requirements. The collected plants are cleaned with sterile water and dried at 95℃ for more than 36 hours, and then the plant body is cut and crushed by a crusher. After completion, the crushed plant materials are put into a carbonization furnace for high-temperature pyrolysis at 500-600℃ and stable carbonization for 2 hours, and then cooled to room temperature after carbonization. Biochar can also be purchased directly from the market.

[0048] Biochar provides sufficient adsorption sites for the material itself to adsorb pollutants in the water. Its excellent ion exchange capacity and strong interaction between various surface functional groups and pollutants promote the occurrence of this process, which directly reduces the concentration of pollutants in the water to reduce environmental risks. As a carbon source, biochar provides energy for plants, increases organic carbon in the water to inhibit the proliferation of algae, and provides essential nutrients for attached microorganisms to promote their growth, metabolism and activity, thereby enhancing the microorganisms' ability to degrade and assimilate pollutants in the water. After the microorganisms attach to its surface to form a biofilm, they can also directly adsorb particulate pollutants in the water. In addition, biochar can also enhance the denitrification of rivers by improving the diversity and composition of microbial communities.

[0049] 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 oxide hydroxide), which has a large adsorption capacity for phosphorus. Scrap iron, as a byproduct, is more suitable for use in the present invention than nano-iron due to its spiral shape, low cost and low possibility of clogging. In the present invention, the scrap iron chips are purchased from surrounding factories, with a length of 8-23 cm, a spiral curved shape, and are cut before use; after testing, these scrap iron chips are mainly composed of 95.8% iron, 3.24% carbon and 0.96% other elements (Mn, Ti, etc.).

[0050] 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.

[0051] Preferably, the mass ratio of biochar to iron filings is 1:9. This ratio is obtained through a laboratory gradient experiment; the gradient experiment only studies the effects of biochar and iron filings on pollutants in water, and finds that when 1 part of biochar and 9 parts of iron filings are added, the removal rates of nitrate, total nitrogen and total phosphorus are improved at the same time, while the richness, diversity and uniformity of the microbial community are improved, and the abundance of Nitrospira and Sulfur Microorganisms is increased.

[0052] The planting matrix 1 provided by the present invention promotes each other and efficiently adsorbs pollutants. Effectively utilizing the two byproducts, plant biochar and scrap iron, can simultaneously improve the removal rates of nitrogen and phosphorus in polluted water bodies. After adding iron, the degradation of low molecular weight carbohydrates can be improved. At the same time, biochar promotes the oxidation of iron and improves the removal rate of total phosphorus (TP). The combined use of the two is also beneficial to the richness, diversity and uniformity of the microbial community, and enhances heterotrophic or autotrophic denitrification; some substances released by plant biomass are beneficial to the oxidation of iron, thereby increasing the rate of denitrification and dephosphorization in water bodies.

[0053] 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 a ball, air-dried at room temperature to constant weight, and then placed in a muffle furnace at 600°C for 6 min, taken out, and cooled at room temperature for 18 hours to prepare 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 2 / g. Alum sludge is a by-product of the water purification process of the water plant. The sludge from the water plant after precipitation contains a large amount of active aluminum and aluminum ions, has good phosphorus absorption, and can effectively remove phosphorus from eutrophic water; alum sludge ceramsite can also provide more adhesion area for microorganisms, and is 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, and the microorganisms related to the degradation of organic pollutants in water attached to its surface can play a role in sewage treatment.

[0054] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with specific embodiments.

[0055] The experimental site in the following embodiments and comparative examples is Paihe River, one of the rivers entering the lake on the west side of Chaohu Lake. Paihe River is a heavily polluted river. The pollution entering the river is mainly industrial sewage and wastewater along the river in Xiaomiao Town and Shangpai Town, domestic sewage in the riverside communities, sewage treatment plants in the Economic Development Zone, and tail water from 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 67km long, with a basin area of ​​586 square kilometers. There are 8 tributaries of Paihe River, and the basin area 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, Gugeng 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, and the difference in pollutants in the water does not affect the comparability of the experimental results.

[0056] Example 1 A method for river water ecological restoration based on the use of an ecological floating blanket comprises the following steps: S1. River channel selection: The river channel is the receiving water body for the tailwater of the industrial sewage treatment plant. A small fence facility is set up in the river channel. The upper edge of the fence is 1 m 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 5000 m 2 , water flow speed does not exceed 1m / s; S2. Preparation of ecological floating blanket: The ecological floating blanket includes plants, floating mats, carriers, nylon nets, planting substrates and inorganic fillers; The plants in the ecological floating carpet are a combination of irises, windmill grass, water spinach, reeds, and giant hyacinth. The planting density is 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, and the selected plants are domesticated by inoculation of pollutant-degrading bacteria and tolerance experiments; The carrier in the ecological floating blanket is a floating mat mainly made of EVA (ethylene-vinyl acetate copolymer material) with a thickness of 5 cm. A planting basket is installed on the floating mat to fix the roots of the plants. The inorganic filler is suspended by a nylon net at the bottom of the floating mat. The inorganic filler is a combination of zeolite and sponge iron. The inorganic filler has a stabilizing effect on the ecological floating mat and has a strong adsorption function for pollutants in the water. Among the inorganic fillers, the mass ratio of zeolite to sponge iron is 0.8:1. The nylon net containing the inorganic filler is pre-filmed to form a layer of yellow-brown biofilm on its surface. The planting basket is square, and 50 chitosan-potassium alginate coated melamine polyurethane composite foams (referred to as composite foams), 100g biochar and 900g iron filings packed in a mesh bag with a pore size of 2 mm are placed in each planting basket as a planting matrix. The mesh bag is made of nylon. Single floating pad area 50 m 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; 4 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; S3. Selection of fish in the water: The fish are a combination of silver carp, bighead carp and catfish. The ratio of silver carp, bighead carp and catfish is 1:1:1. The density of fish is 9 / m 2 ; S4. Restoration of river water ecology: Six months after the ecological restoration system constructed by ecological floating carpet-fish-microorganism was put into use, the river water environment was improved, achieving harmonious and mutually beneficial symbiosis of plants-animals-microorganisms, and realizing material circulation and energy flow in the river ecosystem.

[0057] Example 2 The difference between Example 2 and Example 1 is only that: (1) The mass ratio of zeolite to sponge iron in the inorganic filler is 1:1; (2) Fifty chitosan-potassium alginate-coated melamine polyurethane composite foams and 1000 g alum sludge ceramsite were placed in each planting basket as a planting matrix.

[0058] Example 3 The difference between Example 3 and Example 1 is only that: (1) The mass ratio of zeolite to sponge iron in the inorganic filler is 1.2:1; (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.

[0059] Example 4 The difference between Example 4 and Example 1 is only that: (1) The mass ratio of zeolite to sponge iron in the inorganic filler is 1:1; (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.

[0060] Comparative Example 1 The only difference between Comparative Example 1 and Example 1 is that no inorganic filler is added.

[0061] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that 1000 g of vermiculite is placed in each planting basket as a conventional planting medium for comparison. The vermiculite has a size of 2-4 mm and is purchased from Hebei Chuangjuman Mineral Products Co., Ltd.

[0062] Experimental data and analysis After 6 months of treatment with the embodiments 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 embodiments 1-4 on the river water environment. The test results are recorded in Table 1, where the unit is %.

[0063] Table 1 Experimental data of ecological floating blankets for improving river water environment in Examples 1-4

[0064] From the data in Table 1, we can see that: 1. The results of Examples 1-4 show that the use of the ecological floating blanket of the present invention has significant effects in degrading and adsorbing pollutants, promoting the growth and reproduction of microorganisms and plants, etc. On the one hand, the ecological floating blanket can degrade and adsorb pollutants in the water, improve water quality, reduce the toxic effects of pollutants on plants and microorganisms, and promote their growth and reproduction. On the other hand, the ecological floating blanket can also provide an attachment matrix for microorganisms, promote the attachment and growth of microorganisms; while fixing plants, it provides absorbable nutrients for aquatic plants. At the same time, the ecological floating blanket can inhibit the growth of algae, effectively prevent eutrophication of water bodies, and provide habitats for aquatic animals and birds, thereby improving the stability of the river ecosystem.

[0065] 2. The results of Examples 1-4 show that the plants, carriers, and substrates of the present invention work synergistically with each other to achieve a better effect of improving the river water environment. If the number and amount of substrates used are reduced or the type of substrate is changed, the effect of improving the river water ecological environment will be adversely affected. Comprehensively comparing Examples 1-4, Example 4 of the present invention is the best example.

[0066] 3. The overall fluoride removal rate in the test results is low. This is because the commonly used treatment methods for fluoride-containing wastewater currently include two main methods: precipitation and adsorption. Research on fluoride removal in sewage treatment plants shows that fluoride removal mainly relies on the adsorption of activated sludge, and microorganisms have almost no purification effect on fluoride. At the same time, the assimilation, absorption and utilization efficiency of fluoride by most aquatic plants and animals is not high. In this test, the removal of fluoride mainly relies on chemical adsorption of the planting matrix and absorption and utilization by the large sedge in the plant, so the overall removal rate is low.

[0067] 4. By 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 rate of each item decreased, indicating that inorganic fillers have a removal effect on traditional organic pollutants and emerging pollutants, but in general, planting matrix, microorganisms and plants play a major role in the removal of pollutants.

[0068] 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.

[0069] 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 of ecological floating carpet-fish-microorganisms is used to improve river water bodies, including the following steps: S1. River channel selection: The river channel is the receiving water body for the tailwater of the industrial sewage 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 blanket: The ecological floating blanket includes plants, carriers, nylon nets, planting substrates and inorganic fillers; the plants in the ecological floating blanket are a combination of irises, windmill grass, water spinach, reeds and giant hyacinth, and the selected plants are inoculated with pollutant-degrading bacteria and domesticated through tolerance experiments; 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 plants. The inorganic filler is suspended through a nylon net at the bottom of the floating mat. The inorganic filler is a combination of zeolite and sponge iron. The nylon net containing 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. S3. Selection of fish in the water: fish purification functional groups are fish that can ingest organic debris and floating algae and have different habits and feeding characteristics; fish are a combination of silver carp, bighead carp and bighead carp; S4. Restoration of river water ecology: Six months after the ecological restoration system constructed by ecological floating carpet-fish-microorganisms was put into use, the river water environment was improved.

2. The method for river water ecological restoration based on ecological floating carpet according to claim 1 is characterized in that: The planting density of plants in the ecological floating carpet is 1 kg seedlings / m 2 The planting ratio of iris, windmill grass, water spinach, reed and bighead carp 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 release density is 9 / m 2 .

3. The method for river water ecological restoration 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 method for river water ecological restoration based on ecological floating carpet according to claim 1 is characterized in that: The plant acclimatization 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 be between 0.8 and 1.

2. The culture medium was centrifuged to harvest the cells, and then resuspended in 0.9% (w / v) NaCl solution. The optical density of each bacterial strain was adjusted so that the cell number was 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 20 L 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 contaminated water with a phenol concentration of 300 mg / L. After sterilizing the contaminated water and the surface of the plant roots, 150 ml of bacterial inoculum was added to the contaminated water and the plant seedlings were cultured for 10 days.

5. The method for river water ecological restoration based on ecological floating carpet according to claim 1 is characterized in that: The nylon mesh pre-film treatment process in step S2 is as follows: (1) After soaking the nylon net in clean water for 30 h, hang it in a container containing 50 L of test water; the test water is the water taken from the river in step S1; (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.

6. The method for river water ecological restoration based on ecological floating carpet according to claim 1 is characterized in that: The preparation steps of the chitosan-potassium alginate coated melamine polyurethane composite foam are as follows: 3 The melamine polyurethane foam was immersed in a chitosan-acetic acid solution and subjected to ultrasound for 30 min to obtain a first product; the first product was then immersed in a potassium alginate solution with a concentration of 1.0 g / L, and was taken out from the solution after standing at room temperature for 1 h to obtain a second product; finally, the second product was immersed in a 6% calcium chloride solution for 30 h and naturally dried to obtain a chitosan-potassium alginate coated melamine polyurethane composite foam; The biochar is made from sterilized plant raw materials by pyrolysis at 500-600°C and stable carbonization for 2 hours; The scrap iron is in a spiral shape with 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 at room temperature to constant weight, 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.

7. The method for river water ecological restoration based on ecological floating carpet according to claim 1 is characterized in that: In each of the planting baskets, 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.

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

9. The method for river water ecological restoration based on ecological floating carpet according to claim 1 is characterized in that: 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.

10. The method for river water ecological restoration based on ecological floating carpet according to claim 1, characterized in that: 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 filled in a mesh bag, and 500 g of alum sludge ceramsite were placed.

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