CN107052041B

CN107052041B - Method for efficiently restoring polluted wetland by utilizing artificial ecosystem

Info

Publication number: CN107052041B
Application number: CN201710266396.8A
Authority: CN
Inventors: 杜道林; 李健
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-04-21
Filing date: 2017-04-21
Publication date: 2020-11-10
Anticipated expiration: 2037-04-21
Also published as: CN107052041A

Abstract

The invention discloses a method for efficiently repairing a polluted wetland by utilizing an artificial ecosystem, which is characterized in that scientific configuration is carried out according to different longitudes and latitudes, different humiture and different coastal pollution types, arbor and shrub, herbaceous plants and benthonic animal ecosystems are constructed artificially, and a special sediment microbial community is formed naturally, so that heavy metals and organic pollutants in the polluted wetland are quickly and effectively absorbed and converted by microorganisms and are absorbed and extracted by plants. The invention ensures ecological benefit and maximum restoration efficiency, greatly reduces restoration cost and can generate certain economic benefit. Not only make full use of the difference of the ecological niches of the overground part and maximize the utilization rate of the vertical space, but also maximize the contact area of the rhizosphere microorganisms and the benthonic animals in the underground space, thereby providing a new idea of ecological restoration.

Description

Method for efficiently restoring polluted wetland by utilizing artificial ecosystem

Technical Field

The invention relates to the field of wetland restoration, in particular to a method for efficiently restoring a polluted wetland by utilizing an artificial ecosystem.

Background

At present, heavy metal and organic matter pollution becomes an important obstacle affecting economic development and human health, and has been paid great attention in international scope. The wetland pollution problem in China is particularly prominent, and sewage from modern industry, mining industry and urban life is continuously discharged into rivers, lakes and even oceans, which seriously affects the economic development, human health and living environment in China. The wetland pollution causes great loss to fishery in China and simultaneously forms great obstruction to the development of the fishery.

The method for remedying wetland pollution comprises a chemical method, a physical method and a biological method. The former two have quick effect but high cost, are easy to cause secondary pollution and do not have the principle of environmental sustainability. The bio-extraction method has become one of the focuses of researchers in recent years, because of its good environmental friendliness and ecological sustainability.

The existing ecological restoration technology of the polluted coastal wetland is less, and is mostly seen in the restoration technology of the polluted land soil, and the public number is as follows: 201310538655.X, named: the invention patent publication of the method for ecologically restoring cadmium-polluted soil by utilizing turfgrass mentions that the turfgrass dens roots are adopted to extract heavy metals in the cadmium-polluted soil; the publication number is: 201410778967.2, the name is: the invention discloses a method for restoring soil ecology in rare earth mining area by using herbaceous plants, which is characterized in that animal wastes are used for improving soil, and then a plurality of herbaceous plants are sowed for restoring vegetation; the publication number is: 201410018435.9, the name is: the invention relates to a method for ecologically restoring heavy metal contaminated soil, which adopts fast-growing bamboo willow to extract a plurality of heavy metals in the heavy metal contaminated soil; the publication number is: 201610337938.1, the name is: the invention discloses a construction method of a comprehensive heavy metal polluted soil ecological restoration system.

Although the technologies can generate certain environmental benefits and achieve certain heavy metal extraction effects, the following problems exist: 1) most of the methods are not suitable for restoring polluted wetlands, especially coastal wetlands; 2) ecological benefits are not maximized; 3) a high-speed and high-efficiency heavy metal extraction mode is not formed; 4) economic benefits are ignored when the ecological benefits are explained; 5) most of the technologies have the risk of ecological system collapse due to monotonous species or communities, and the reproducibility is not high; 6) some techniques are cost prohibitive; 7) some techniques extract single heavy metal types, or do not mention the remediation of organic pollutants; 8) some techniques use chelating agents, which are prone to secondary pollution.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a method for efficiently restoring polluted wetlands by utilizing an artificial ecosystem, which overcomes the defects in the prior art, can be derived into an ecosystem suitable for restoring the pollution of any wetland under the condition of scientific species configuration, and has good ecological value and development prospect.

The technical problem to be solved by the invention is realized by the following technical scheme:

a method for efficiently restoring polluted wetlands by utilizing an artificial ecosystem is characterized in that scientific configuration is carried out according to different longitudes and latitudes, different humiture and different coastal pollution types, arbor and shrub, herbaceous plants and benthonic animal ecosystems are constructed artificially, and a special sediment microbial community is formed naturally, so that heavy metals and organic pollutants in the polluted wetlands are absorbed and converted by microorganisms quickly and effectively and are absorbed and extracted by plants.

Preferably, in the above technical solution, the method includes the steps of:

1) selecting arbor plants, wherein seedlings of the arbor plants come from cryptofetal embryonic hypocotyl development, arbor hypocotyls of the arbor plants are picked in arbor forests in self-wetland in april and may month every year, each arbor plant is about 20-30 cm, and the arbor plants are artificially and directly planted in the polluted wetland to automatically take roots and develop, and the depth of each arbor plant is about 5-8 cm; or cultivating for one month to two months, and transplanting the trees into the polluted wetland after the roots and 2-4 pairs of true leaves of the trees grow, wherein the depth is about 5-8 cm, and the planting density is 30-40 cm multiplied by the row spacing of 40-50 cm.

2) Selecting arbor and shrub, wherein seedlings of the arbor and shrub come from embryonic axis development, arbor and shrub embryonic axes are picked from the wetland every nine and ten months, each arbor and shrub embryonic axis is about 5cm, and the arbor and shrub is artificially and directly planted among arbors and self-rooted and developed by the arbor and shrub; or cultivating for one month to two months, and transplanting the trees and shrubs in the polluted wetland after the embryonic axis of the trees and shrubs grows roots and 2-4 pairs of true leaves, wherein the depth is about 5-8 cm.

3) Selecting perennial herbaceous plants, wherein the perennial herbaceous plants are from tissue culture or seed culture, the herbaceous plants are subjected to stem section culture after propagation, and seedlings are cut in arbor forests; or after collecting herbaceous plant spores, cultivating the herbaceous plant spores indoors until 5-6 young leaves are obtained, and transplanting and cutting the herbaceous plant spores under an arbor forest.

4) Selecting benthonic animals, and putting the captured, purchased or cultured benthonic animals into the polluted wetland of vegetation trees, arbors and shrubs, perennial herbs and ciliate desert grass in autumn.

Preferably, in the technical scheme, the arbor is selected from woody plants which have strong salt tolerance, strong flooding resistance, strong adaptability and stress resistance, high growth speed, high accumulation or degradation characteristics of various pollutants and certain economic value.

Preferably, in the above technical scheme, the arbor is one or a combination of more than one of avicennia marina, solanum delicicum and bruguiera gymnorrhiza.

Preferably, in the above technical solution, the arbor and shrub is selected from arbor and shrub having strong salt tolerance, strong flooding tolerance, strong adaptability and stress tolerance, fast growth rate, and high accumulation or degradation characteristics of various pollutants.

Preferably, in the above technical solution, the arbor and shrub is a tung tree.

Preferably, in the above technical scheme, the perennial herbaceous plants are selected from herbaceous plants with strong salt tolerance, strong adaptability and stress resistance, fast growth speed, high tolerance and high accumulation or degradation characteristics of various heavy metals and/or organic pollutants.

Preferably, in the above technical solution, the perennial herb is one or more of vetiver, reed, calamus, hippocampus, purslane, sage and ciliate desert-grass.

Preferably, in the above technical scheme, the benthonic animals are selected from common benthonic animals which are easy to obtain or culture, strong in mobility, small in range of motion and easy to live and store.

Preferably, in the above technical scheme, the benthonic animals are one or a combination of perinereis aibuhitensis and the tidal crabs.

The technical scheme of the invention has the following beneficial effects:

(1) space utilization maximization: different plants in construction have different ecological niches and root depths, the greening of the vertical space of the overground part reaches the maximization, and the area of the root-soil interface of the underground part is maximized.

(2) Time utilization maximization: taking vetiver grass, hippocampus and ciliate desert-grass as examples, the growth cycle and the growth speed are different, the biomass on the ground is large, and the vetiver grass can be harvested for many times in different time periods every year. The coupling effect between benthonic animals, microorganisms and plants greatly improves the extraction and degradation rate of pollutants.

(3) Wide application range and high reproducibility: the construction provides a complex and stable ecosystem model, for example, the avicennia marina, the tung tree, the vetiver grass, the reed, the calamus, the hippocampus and the ciliate desert grass are all plants with high pollutant stress resistance and high accumulation, and are easy to be planted and survive in most polluted wetlands of temperate zone and subtropical zone. Meanwhile, the construction can be popularized and developed into other species combinations suitable for polluted wetlands in other environments.

(4) Absolute environmental friendliness: the benthonic animals (such as perinereis aibuhitensis) replace the defect that the chelating agent is utilized to increase the plant absorption rate in the prior art, completely avoid secondary pollution and have absolute environmental friendliness.

(5) Economic benefit: taking vetiver as an example, the method has the characteristics of fast growth, high biomass and high heat value, can be used for biogas fermentation after being harvested, can produce 550-700ml biogas per 1000g fresh leaves, and provides certain economic benefit.

(6) The stability of the ecological system: the complexity of the species in this construction determines the stability of this artificial ecosystem.

In conclusion, the method for efficiently restoring the polluted wetland by using the artificial ecosystem greatly reduces the restoration cost and can generate certain economic benefit while ensuring the ecological benefit and maximizing the restoration efficiency. Not only make full use of the difference of the ecological niches of the overground part and maximize the utilization rate of the vertical space, but also maximize the contact area of the rhizosphere microorganisms and the benthonic animals in the underground space, thereby providing a new idea of ecological restoration.

Detailed Description

Specific examples of the invention are described in detail below to facilitate a further understanding of the invention.

All experimental procedures used in the following examples are conventional unless otherwise specified.

Example 1 selection of materials

(1) And (3) arbor: selecting woody plants which have strong salt tolerance, flooding resistance, strong adaptability and stress resistance, high growth speed, high accumulation or degradation characteristics of various pollutants and certain economic value.

Preferably: small arbor avicennia marina, kandelia candel and bruguiera gymnorrhiza which have high tolerance and high-efficiency fixing ability to various heavy metals and have the ability of absorbing and degrading organic pollutants.

(2) And (3) arbor and shrub: selecting arbor and shrub with strong salt tolerance, flooding tolerance, strong adaptability and stress tolerance, and fast growth rate, and has the characteristics of high accumulation or degradation of various pollutants.

Preferably: the arborescent and shrub plant of the coastal wetland, namely the tung tree, has the advantages of negative resistance and normal growth in loose forests.

(3) Perennial herbaceous plants: selecting herbaceous plants with strong salt tolerance, strong adaptability and stress resistance, high growth speed, high tolerance to various heavy metals and/or organic pollutants and high accumulation or degradation characteristics.

Preferably: the herbaceous plant vetiver with high economic value, large biomass and capability of adsorbing and fixing various heavy metals and organic pollutants; creeping plant hippocampus which has a high accumulation capacity for cadmium and has characteristics of degrading organic pollutants (such as phenanthrene) in association with rhizosphere microorganisms; purslane which is salt-tolerant, flooding-tolerant and has high accumulation property for cadmium; salt-tolerant, flooding-resistant and reed and calamus with high accumulation characteristics to lead, zinc, chromium, cadmium and the like; the salt land sage has high accumulation on cadmium, can quickly spread and has the functions of preventing sand and fixing soil; the ciliate desert-grass has strong salt tolerance, high enrichment performance on various heavy metals (such as arsenic and lead), strong tolerance on organic pollutants (such as polycyclic aromatic hydrocarbon) and high removal rate.

(4) Benthonic animals: taking tropical and subtropical coastal wetlands as examples, common benthonic animals which are easy to obtain or culture, strong in mobility, small in moving range and easy to live and store are selected.

Preferably: perinereis aibuhitensis and Boschniakia hainanensis.

Example 2 construction of ecosystem

Experimental materials: avicennia marina, tung tree, hippocampus japonicus, ciliate desert-grass, vetiver grass and perinereis aibuhitensis.

1) The method comprises the steps of selecting arbor plant avicennia marina, wherein seedlings of the arbor plant avicennia marina are grown from cryptofetal embryonic axis, and the avicennia marina embryonic axis is picked from the avicennia marina wetland in april and may. In order to prevent the tidal power from reducing the planting rate of the avicennia marina hypocotyls, cultivation is carried out for one month to two months, and after the avicennia marina hypocotyls grow roots and 2-4 pairs of true leaves, the plants are planted in the polluted wetland with the depth of about 5-8 cm. The planting density is 30-40 cm of plant spacing and 40-50 cm of row spacing.

2) Selecting arbor and shrub tung tree, wherein the seedling comes from the development of embryonic axis, and the embryonic axis of the tung tree is collected from the tung tree forest in the mangrove wetland every nine or ten months. Each about 5 cm. Can be artificially and directly planted in the avicennia marina forest to automatically take root and develop; or after cultivation for one month to two months, after the embryonic axis of the tung tree grows out roots and 2-4 pairs of true leaves, the tung tree is planted in the polluted wetland with the depth of about 5-8 cm.

3) Selecting perennial herb such as hippocampus, ciliate desert-grass and vetiver grass, wherein the vetiver grass can be obtained from tissue culture or seed culture, culturing stem segments (two stem segments are one stem segment) after the propagation of the hippocampus, and cutting the seedlings in the avicennia marina forest. In order to prevent the tide power from reducing the germination and planting rate of ciliate desert-grass spores, 5-6 young leaves are cultivated indoors after the spores are collected, and the ciliate desert-grass spores are transplanted and inserted into the white-bone loaves.

The growth speed of the vetiver grass is obviously higher than that of the avicennia marina, but the avicennia marina has better negative resistance in the early growth and development stage and also has positive preference after being planted, so that interplanting can be carried out without waiting for the avicennia marina to form a forest.

4) Selecting the perinereis aibuhitensis as the benthonic animal, and putting the captured, purchased or cultured benthonic animal into the polluted wetland of vegetation trees, trees and shrubs and perennial herbs in autumn.

The species composition in the ecological system needs to fully consider the stable group plant colony of different climatic zones or the ecological niche composition of the ecological system structure.

The invention only takes the plants as the preferred scheme, and the species can be matched and selected by the skilled person according to the needs.

Experimental example 1

The sediments are collected from the south coast forest (24 degrees in northern latitude, 24 degrees in east longitude, 117 degrees in east longitude, 55 degrees in west China) of natural protection area of Fujian Zhongzhou Longhai Zhonghai county Fuhai Tu province, Fujian Zhonghai county, Fujian province, Yuanjian Konghong forest, the sediments are fully mixed, CdCl2(0, 1, 2, 4 mg/kg. Mixing thoroughly once every five days, keeping the surface of the sediment covered with water during activation, and supplementing the evaporated water loss with ultrapure water. Adding about 3kg of activated sediment into each seedling pot, repeating three treatments each time, transplanting 4 pieces of avicennia marina with similar growth vigor and two pairs of true leaves in each pot, and treating for 45 days. The results are shown in Table 1.

TABLE 1

The result shows that the distribution rule of cadmium in the avicennia marina tissues is root > stem > leaf. The cumulative amount of cadmium in the root has exceeded the concentration of cadmium in the surrounding environment. The four treatments have no obvious influence on the growth of the avicennia marina, and the biomass of roots, stems and leaves has no obvious change, which indicates that the avicennia marina has certain tolerance capability.

Experimental example 2

The method adopts soil culture pot culture and laboratory culture. Five groups of heavy metal treatments are performed, each group is repeated by three times, and the concentrations are respectively as follows: 0. 10, 30, 60, 120mg/kg & DW, 5kg of dry soil is used in each pot. Heavy metals Cd, Cr, Pb and Ni are added into the potting soil according to the set concentration and are fully and uniformly mixed. Selecting the same batch of transplanted strong vetiver seedlings with the height of about 20cm, and uniformly planting 5 seedlings in each pot. And after planting, placing the plants in a greenhouse, pouring deionized water into the greenhouse regularly to moisten the soil, and keeping the temperature at 25-29 ℃. After culturing for 60 days, respectively harvesting the overground part and the underground part, washing with deionized water, and drying at 70 ℃ to constant weight after enzyme deactivation. And (4) grinding and sieving the mixture, and then measuring the contents of Cd, Cr, Pb and Ni in the overground part and the underground part. The results are shown in Table 2.

TABLE 2

The result shows that the vetiver grass has strong enrichment capacity to heavy metals Cd, Cr, Pb and Ni, particularly the amount of the heavy metals enriched in the root system can reach 80 times of that in the soil, and the accumulation amount of the heavy metals on the ground can reach 56 times of that in the soil.

Experimental example 3

Culturing the hippocampus plant in a greenhouse for one month, wherein the culture medium is Hoagland nutrient solution culture, the temperature is 25-28 ℃, the salinity is 27 per mill, and natural illumination is adopted. Preparing artificial seawater and applying Hoagland nutrient solution and 1 mg.L < -1 > phenanthrene to obtain the hippocampus culture solution. 500mL of culture solution is taken from a glass culture bottle, and then the glass culture bottle is transferred into a hippocampus plant which has uniform growth, vigorous activity and no plant diseases and insect pests, and simultaneously a control group (CK) without hippocampus is made, 3 times of treatment are repeated, the mouth of the culture bottle is coated with a sealing film after the culture bottle is shaded, and the direct volatilization of phenanthrene is reduced. All treatment groups were incubated in a light incubator. The temperature is 26 +/-1 ℃, the illumination intensity is 4000lx, and the illumination time is 12 hours/day. And (3) determining the phenanthrene content in the plant sample at the initial stage of the experiment and after 5 days of culture and the residual concentration of phenanthrene in the culture solution after 5 days of culture. The results are shown in Table 3.

TABLE 3

According to the experimental result, the removal rate of the sea horse teeth to the phenanthrene in the sea water after 5 days reaches 92.86%. However, the accumulation amount of the sea horse teeth to phenanthrene is far less than the removal amount of the sea horse teeth to phenanthrene, which shows that the sea horse teeth can remove phenanthrene through plant metabolism, plant volatilization or combined microbial action, have the capability of rapidly and efficiently removing the concentration of phenanthrene in seawater, and are coastal beach plants with great restoration potential.

Experimental example 4

In the experiment for purifying the heavy metal polluted water body by the salt tolerant aquatic plant, reed and calamus are used as test objects, and the indoor simulation of the coastal wetland is adopted to compound the heavy metal polluted water body. The culture temperature is 25-28 ℃. The Hoagland nutrient solution with the salinity of 6 per thousand is used as a culture medium, and the heavy metals simulating the polluted water are selected from lead, zinc, cadmium and chromium, and the contents of the heavy metals are respectively 30mg/l, 300mg/l, 10mg/l and 20 mg/l. Plants which grow healthily and have similar growth conditions are selected, washed clean by ultrapure water, and then tested according to the groups of reed, calamus, reed and calamus. Before the experiment, the plants are acclimated to the salt tolerance so as to adapt to the high-salt water until the salinity is 6 per mill. The removal rate of the plants to various heavy metal elements in the water body is basically kept unchanged in the domestication process, which shows that the plants have higher salt tolerance. Sampling after culturing for 60 days, detecting the contents of lead, zinc, cadmium and chromium in the water body, and detecting the biomass of the plants. The water lost by evaporation and the like was replenished every 3 days.

As can be seen from the following table, the plant has the purification effect of reed and acorus calamus reed on the polluted water. The reed and calamus configuration has the best purification effect on heavy metal pollution. The results are shown in Table 4 (purification effect of the plant composite arrangement on eutrophic pollution).

TABLE 4

Plant combination	Salinity (‰)	Lead (II)	Zinc	Cadmium (Cd)	Chromium (III)
						Reed	6	81.15	79.84	83.00	69.00
Acorus calamus	6	83.73	83.53	85.74	75.14
						Reed and calamus	6	88.15	91.68	89.74	82.77

Experimental example 5

In order to further verify the effect of the systematic combination of the trees, the shrubs and the herbaceous plants on the extraction of heavy metals under the soil culture condition, the heavy metal gradient pollution is artificially set, the field pollution condition is simulated, and the influence of the systematic combination of the trees, the shrubs and the herbaceous plants on the migration occurrence of various heavy metals in the coastal wetland sediments is measured.

The sediments are collected from the Murraya Koenigii Kong, Fujian, Zhangzhou, Longhai, Zhengcao, Cambodia, and Korea, and the sediments are fully mixed, and are activated for two months by applying cadmium, chromium, lead 10, 50 and 100 mg/kg.DW with different concentrations. And (3) measuring the concentrations of cadmium, chromium and lead in the activated sediment, planting the avicennia marina, the tung tree, the vetiver grass, the calamus and the reed (a system group), and simultaneously setting a control group of the avicennia marina, the tung tree (a woody group), the vetiver grass, the calamus and the reed (a herbaceous group). The treatment was carried out in a greenhouse for 6 months, the loss of evaporated water being made up with ultrapure water. The results are shown in Table 5.

TABLE 5

The results show that: the absorption rate of cadmium, chromium and lead in the sediment, namely the combination of avicennia marina, tung tree, vetiver, calamus and reed (system group), the combination of vetiver, calamus and reed (herbaceous group), the combination of avicennia marina and tung tree (woody group), so that the configuration of the arbor, shrub and herbaceous plant system has great promotion effect on improving the heavy metal restoration efficiency. The combination of several different species has the synergistic effect, and the effect is better after the combination is matched with the benthonic animals.

In the technology, the arbor and shrub are selected, for example, the avicennia marina and the tung tree, are mangrove plants, have developed root systems, are high-salt-resistance plants living in coastal intertidal zones, and have the capacity of enriching various heavy metals such as lead, copper, zinc, cadmium, chromium and the like. The herbaceous plant vetiver with high economic utilization has strong salt tolerance and strong flooding resistance.

The tolerance of the vetiver grass to common heavy metal pollution (such as arsenic, cadmium, copper, chromium, lead, mercury, nickel and zinc) is more than 10-100 times of that of common plants, and the enrichment capacity of the vetiver grass to the heavy metal follows the rule that Zn is more than Pb and more than Cu is more than Zn-Pb-Cu.

The herbaceous plants including the hippocampus, the ciliate desert-grass, the calamus, the reed and the like can enrich heavy metals in large quantity, have the capacity of degrading organic pollutants by combining rhizosphere microorganisms, and have a good repairing effect on sediments which are compositely polluted by the heavy metals and the organic pollutants.

The benthonic animals like perinereis aibuhitensis and the like have small moving range and no possibility of causing pollution diffusion, and not only can improve the anaerobic environment of sediments through self disturbance, increase the contact area of dissolved oxygen and the sediments and change the physical and chemical properties of the sediments. Meanwhile, the perinereis aibuhitensis has better tolerance to heavy metals such as cadmium and copper, the exchangeable heavy metal content in a large amount of discharged excrement is very high, and the extraction of plant roots to the heavy metals is facilitated.

The invention aims at the problems that the pollution source is complex, single heavy metal or organic pollutant does not exist in the coastal wetland pollution, the pollutant has other characteristics in the enrichment level in the sediment, and species with different enrichment pollutant types and different growth periods and root system depths are configured to improve the contact area of root soil. The introduction of the perinereis aibuhitensis strengthens the repairing effect, and maximizes the time and space utilization rate of biological extraction or degradation. Meanwhile, the construction artificially configures complex plant populations according to different plant ecological niche differences, so that the utilization rate of the vertical space of the overground part is greatly improved, the greening area of the coastal wetland is maximized, and the system stability is maximized. The construction ensures ecological benefit and also provides economic benefit.

The invention discloses a method for efficiently restoring a polluted wetland by utilizing an artificial ecosystem. The method is characterized in that scientific seed selection and reasonable configuration are carried out according to different longitudes, latitudes, temperatures and humidity and different coastal pollution types, an arbor-arbor bush-herbaceous plant-benthonic animal ecosystem is constructed artificially, and a special sediment microbial community is formed naturally, so that heavy metals, organic pollutants and the like in the polluted wetland are absorbed and transformed by microorganisms quickly and effectively and are absorbed and extracted by plants. The ground vegetation is artificially harvested to achieve the effect of efficiently purifying the soil. The construction comprises screening woody plants, shrubs, vines and herbaceous plants with high tolerance and removal characteristics on heavy metals and/or organic pollutants, cultivating and planting arbors and shrubs, cutting herbaceous plants and introducing benthonic animals. Scientific seed selection and reasonable configuration are carried out on the overground vegetation structure by utilizing different interspecific relations and ecological niches, a complex independent stable plant community is formed, meanwhile, beneficial soil benthonic animals are introduced, a complex rhizosphere ecological circle formed by underground roots, soil and microorganisms is formed in a combined mode by combining a soil microorganism system, and a complete artificial ecosystem is constructed. The stable system changes the original biogeochemical circulation path of the pollutants in the sediment, increases the bioavailability of the pollutants, and greatly improves the extraction and removal rate of the pollutants and the repair rate of the soil. The invention fully utilizes the difference between the ecological niche characteristics of the overground part and the ecological niche of the underground root system among different tolerant plant species, takes benthonic animals with weak maneuverability as assistance, and greatly increases the bioavailability of pollutants and the absorption area of the pollutants by the activation or decomposition action of rhizosphere and a special microbial community. Not only has the sufficiency of time-space utilization, but also shows good simplicity economically, and has excellent friendliness in environment. Through the construction, the pollutant content of the coastal sediments can be quickly and effectively reduced, additional ecological functions such as bank protection and dike fixation, waste filtration and coastal environment greening are provided, and a certain economic benefit can be formed by selecting appropriate plants while the construction cost and the manual maintenance cost are effectively reduced.

Although the present invention has been described with reference to the above embodiments, it should be understood that the present invention is not limited thereto, and various changes and modifications may be made by those skilled in the art without departing from the spirit and scope of the present invention.

Claims

1. A method for efficiently repairing a polluted wetland by using an artificial ecosystem is characterized in that scientific configuration is carried out according to different longitudes, latitudes, temperatures and humidities and different coastal pollution types, an arbor, arbor and shrub, herbaceous plants and benthonic animal ecosystem is constructed artificially, and a special sediment microbial community is formed naturally, so that heavy metals and organic pollutants in the polluted wetland are quickly and effectively absorbed and converted by microorganisms and are absorbed and extracted by plants; the method comprises the following steps:

1) selecting arbor plants, wherein seedlings of the arbor plants come from embryonic axis development, arbor embryonic axes are picked in arbor forests in self-wetland in april and may month every year, each arbor tree is about 20-30 cm, and the arbor plants are artificially and directly planted in the polluted wetland to automatically root and develop, and the depth is about 5-8 cm; or cultivating for one month to two months, and planting in the polluted wetland after the root and 2-4 pairs of true leaves of the arbor grow, wherein the depth is about 5-8 cm, and the planting density is that the plant spacing is 30-40 cm and the row spacing is 40-50 cm;

2) selecting arbor and shrub, wherein seedlings of the arbor and shrub come from embryonic axis development, arbor and shrub embryonic axes are picked from the wetland every nine and ten months, each arbor and shrub embryonic axis is about 5cm, and the arbor and shrub is artificially and directly planted among arbors and self-rooted and developed by the arbor and shrub; or cultivating for one month to two months, and transplanting the trees and shrubs in the polluted wetland after the embryonic axis of the trees and shrubs grows roots and 2-4 pairs of true leaves, wherein the depth is about 5-8 cm;

3) selecting perennial herbaceous plants, wherein the perennial herbaceous plants are from tissue culture or seed culture, the herbaceous plants are subjected to stem section culture after propagation, and seedlings are cut in arbor forests; or collecting herbaceous plant spores, culturing the herbaceous plant spores indoors until 5-6 young leaves are obtained, and transplanting and cutting the herbaceous plant spores into arbor forests;

4) selecting benthonic animals, and putting the captured, purchased or cultured benthonic animals into the polluted wetland of vegetation trees, arbors and shrubs, perennial herbs and ciliate desert grass in autumn;

the arbor is one or more of avicennia marina, Kandelia candel and Bruguiera gymnorrhiza; the arbor and shrub is a tung tree; the perennial herb is one or more of vetiver, reed, calamus, hippocampus, purslane, sage and ciliate desert-grass.

2. The method for efficiently remediating a contaminated wetland using an artificial ecosystem as claimed in claim 1, wherein the arbor is selected from woody plants having strong salt tolerance, flooding tolerance, strong adaptability, stress tolerance, fast growth speed, high accumulation or degradation characteristics of various pollutants, and certain economic value.

3. The method for effectively remediating a contaminated wetland using an artificial ecosystem as claimed in claim 1, wherein the trees and shrubs are selected from the group consisting of trees and shrubs with strong salt tolerance, flooding tolerance, adaptability, stress tolerance, fast growth rate, and high accumulation or degradation characteristics of various pollutants.

4. The method for effectively remediating a contaminated wetland using an artificial ecosystem as claimed in claim 1, wherein the perennial herbs are selected from the group consisting of herbaceous plants with strong salt tolerance, strong adaptability and stress resistance, fast growth speed, high tolerance and high accumulation or degradation characteristics of various heavy metals and/or organic pollutants.

5. The method for effectively remediating a contaminated wetland using an artificial ecosystem as claimed in claim 1, wherein the benthonic animals are selected from the group consisting of common, easily obtained or cultured, highly active, small-range, and easily living and storable benthonic animals.

6. The method for efficiently remedying the polluted wetland using the artificial ecosystem as claimed in claim 5, wherein the benthonic animals are one or a combination of perinereis aibuhitensis and the tidal crabs.