Wave dissipation type lake and reservoir wetland ecological restoration method

Abstract

The invention relates to the technical field of ecological restoration, and particularly discloses a wave dissipation type lake and reservoir wetland ecological restoration method. The wave-resistant short dike is built at the bottom of the lakeshore levee slope and mainly plays a role in protecting the lakeshore and an aquatic plant planting area, and due to fluctuation of the water level, the wave-resistant short dike can intercept part of dry branches, fallen leaves and soil, can serve as a new plant recovery area and can also serve as a shelter and a habitat of aquatic organisms; the ecological restoration wetland area is established between the lakeshore levee slope and the wave-resistant short levee, different emergent aquatic plants and submerged plants are planted, the wetland structure is optimized, the wetland landscape is beautified, and the propaganda and education effects on tourists and surrounding people can be achieved; meanwhile, due to the fact that wind is heavy and waves are high in middle and large lakes and reservoirs, newly repaired embankments and wave-resistant short embankments are prone to being scoured by water waves and damaged, even the newly built embankments face the danger of being destroyed by water, and meanwhile various aquatic plants, aquatic plants and the like which are planted are destroyed, wind waves can be effectively reduced by building the steel column wave-resistant net.

Description

Technical Field

[0001] The invention relates to the technical field of ecological restoration, and in particular to a wave-breaking lake wetland ecological restoration method. Background Art

[0002] Rivers and lakes play an irreplaceable role in the global water environment system. They are not only an important support for water supply, fishery and water transportation, but also play a key role in microclimate regulation and species diversity protection. The health of rivers and lakes is closely related to human activities. However, excessive exploitation of water resources, ecological damage caused by urbanization, and the discharge of large amounts of production and domestic wastewater have caused serious water pollution in rivers flowing through cities. Excessive input of nutrients such as nitrogen and phosphorus has seriously overloaded the self-purification capacity of rivers and the carrying capacity of the water environment, and some rivers have gradually evolved into slightly polluted rivers. These unpurified river waters eventually flow into lakes and reservoirs, which will inevitably lead to eutrophication of lake waters, degradation of ecosystems and loss of biodiversity, forming a vicious cycle.

[0003] The existing restoration technologies for river, lake and reservoir water environments mainly include physical, chemical and biological methods, and mainly include source control and pollution interception, river dredging, ecological revetments, bypass wetlands, ecological floating beds and other restoration methods. However, most of these use a single restoration method, which is difficult to control the increasingly polluted river and lake water systems.

[0004] For example, Chinese patent document CN201610226495.9 discloses a lake water environment pollution restoration system, including an ecological floating bed floating on the surface of the lake, a plurality of planting beds fixed on the ecological floating bed, an adsorption net and a reaction bed fixed on the bottom of the ecological floating bed, and an algae grid and an aeration pipe arranged on the bottom of the lake; the aeration pipe is connected to an air pump through a ventilation pipe; a plurality of aeration holes are provided on the aeration pipe; at least one inflatable bag is fixed on the algae grid, the inflatable bag is connected to an air supply pipe through an inflatable pipe, and the input end of the air supply pipe is connected to the second output end of the air pump. Although the restoration efficiency of the system is improved, it is not easy to construct in lakes and reservoirs with large winds and waves, and can only be implemented in lakes and reservoirs with small winds and waves and shallow water in local bays. Summary of the invention

[0005] In view of the deficiencies in the prior art, the object of the present invention is to provide a wave-breaking lake wetland ecological restoration method.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme:

[0007] A wave-breaking lake wetland ecological restoration method comprises the following steps:

[0008] S1. Build a wave-breaking embankment at the bottom of the lake bank slope;

[0009] S2. Drive wooden piles obliquely into the lake bank slope to a depth of 1 / 3-1 / 2 of the length of the wooden piles. The wooden piles are arranged along the river channel and located above the wave-breaking dike. The interval between two adjacent wooden piles is 2.5-3m. An eco-bag is fixed on each wooden pile, and the eco-bag is located below the lake surface.

[0010] S3, a steel column wave-breaking net is arranged 8-10m outside the wave-breaking dike, the steel column wave-breaking net comprises a number of channel steels arranged along the river channel, the interval between two adjacent channel steels is 2.5-3m, the channel steels are equipped with a wave-breaking net, and a buoy is arranged on the wave-breaking net;

[0011] S4. Establish an ecological restoration wetland area between the lake bank slope and the wave-breaking dike and plant different aquatic plants.

[0012] Preferably, in step S2, the preparation method of the eco-bag is as follows:

[0013] (1) adding biochar to a sodium hydroxide solution, heating and stirring, and then filtering, washing, and drying to obtain alkali-activated biochar;

[0014] Biochar comes from agricultural waste, such as corn straw biochar, peanut shell biochar, coconut shell biochar, rice husk biochar, etc.

[0015] (2) dispersing the alkali-activated biochar in deionized water, then adding carboxymethyl chitosan and epichlorohydrin thereto, stirring for reaction, and after the reaction is completed, filtering, washing, and drying to obtain modified biochar;

[0016] (3) immersing the modified biochar in a calcium salt solution to chelate calcium ions, then adding the modified biochar with chelated calcium ions to a mixed aqueous solution of calcium nitrate and diammonium phosphate, heating the mixture for reaction, and after the reaction is completed, filtering, washing, and drying the mixture to obtain biochar-loaded hydroxyapatite;

[0017] (4) The biochar-loaded hydroxyapatite and the composite microbial powder are mixed evenly to obtain a mixture, and then the mixture is added to a mixed aqueous solution of sodium alginate and gelatin, shaken and mixed for 24-48 hours, and centrifuged, washed, and dried to obtain gel particles;

[0018] (5) Put the gel particles into a bag made of polypropylene and seal it to obtain an eco-bag.

[0019] Preferably, in step (1), the temperature of the heating and stirring treatment is 40-60° C., and the time of the heating and stirring treatment is 2-5 h.

[0020] Preferably, in step (2), the mass ratio of alkali-activated biochar, carboxymethyl chitosan and epichlorohydrin is 10-15:5-8:4-6.

[0021] Preferably, in step (2), the stirring reaction temperature is 60-80° C., and the stirring reaction time is 3-5 h.

[0022] Preferably, in step (3), the solubility of the calcium salt solution is 10-15 mmol / L, the concentration of diammonium hydrogen phosphate in the mixed aqueous solution is 3-5 mmol / L, and the molar ratio of calcium nitrate to diammonium hydrogen phosphate is 1.5-2:1.

[0023] Preferably, in step (3), the heating reaction temperature is 70-85° C., and the heating reaction time is 48-72 h.

[0024] Preferably, in step (4), the mass ratio of biochar-loaded hydroxyapatite to the composite microbial powder is 10-15:1-3, wherein the composite microbial powder is composed of Shewanella putrefaciens powder and Bacillus subtilis powder, the mass ratio of Shewanella putrefaciens powder to Bacillus subtilis powder is 1-2:1-2, and the number of viable bacteria in both Shewanella putrefaciens powder and Bacillus subtilis powder is not less than 1.0×10 8 cfu / g.

[0025] Preferably, in step (4), the ratio of the mixed material to the mixed aqueous solution is 2-4 g:100 mL.

[0026] Preferably, in step (4), the mass fraction of sodium alginate in the mixed aqueous solution is 3-6%, and the mass fraction of gelatin is 1-2%.

[0027] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0028] (1) The present invention establishes a wave-breaking embankment at the bottom of the lake bank slope, which mainly plays the role of protecting the embankment and the aquatic plant planting area. Due to the rise and fall of the water level, the wave-breaking embankment will intercept some dead branches and leaves and soil, which can be used as a new plant recovery area and can also become a shelter and habitat for aquatic organisms.

[0029] (2) The present invention establishes an ecological restoration wetland area between the lake bank slope and the wave-breaking levee. By planting different emergent plants and submerged plants, the wetland structure is optimized and the wetland landscape is beautified, which can play a propaganda and educational role for tourists and surrounding people.

[0030] (3) Due to the strong winds and high waves in medium and large lakes and reservoirs, which can reach more than 2 meters, newly repaired embankments and wave-breaking dikes are easily damaged by waves. Even newly built embankments are in danger of being washed away, and all kinds of aquatic grasses and plants planted will be destroyed. By building steel column wave-breaking nets, wind and waves can be effectively reduced.

[0031] (4) The self-made eco-bag of the present invention first increases the number of active functional groups on the surface of the biochar by alkali activation treatment, and then grafts carboxymethyl chitosan onto the biochar through the cross-linking effect of epichlorohydrin. On the one hand, the hydrophilicity of the biochar is improved, so that it can be infiltrated faster and the adsorption performance of the biochar is improved. On the other hand, the polymer network structure of carboxymethyl chitosan is conducive to the subsequent loading of hydroxyapatite. In addition, carboxymethyl chitosan can provide a carbon source for microorganisms, thereby improving the ability of microorganisms to degrade ammonia nitrogen. Carboxymethyl chitosan contains a large number of hydroxyl and amino groups, which first chelate calcium ions, and then use the chelated calcium ions as seeds. Nano-hydroxyapatite is further grown. The high specific surface area of ​​nano-hydroxyapatite enables it to provide a large number of adsorption sites, thereby achieving the removal of ammonia nitrogen in wastewater through physical adsorption. At the same time, hydroxyapatite, as an attachment medium for microorganisms, can promote the growth and metabolism of microorganisms, and further promote biological denitrification. The composite microbial agent works together with biochar and hydroxyapatite to better remove pollutants in wastewater. Finally, sodium alginate and gelatin are used for encapsulation. Calcium alginate and gelatin form a cross-linked gel structure, which effectively reduces the leakage of microorganisms. At the same time, calcium alginate and gelatin have good adsorption properties and can adsorb pollutants in water. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic structural diagram of the wave-breaking lake and reservoir wetland ecological restoration provided by the present invention. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below through specific preferred embodiments, but the present invention is not limited to the following embodiments.

[0034] It should be noted that, unless otherwise specified, the chemical reagents involved in the present invention were purchased through commercial channels.

[0035] A wave-breaking lake wetland ecological restoration method comprises the following steps:

[0036] S1. Build a wave-breaking dike at the bottom of the lake bank slope.

[0037] In this step, a wave-breaking levee is built at the bottom of the lake bank slope, and wetland plants are planted on the wave-breaking levee to protect the levee; it mainly plays the role of protecting the levee and aquatic plant planting area, and due to the rise and fall of water levels, the wave-breaking levee will intercept some dead branches and leaves and soil, which can be used as a new plant recovery area, and due to the porous structure of the wave-breaking levee, it can become a shelter and habitat for aquatic organisms.

[0038] S2. Drive wooden piles obliquely into the lake bank slope, with a driving depth of 1 / 3-1 / 2 of the length of the wooden piles. The wooden piles are arranged along the river channel and located above the wave-breaking dike. The interval between two adjacent wooden piles is 2.5-3m, and an ecological bag is fixed on each wooden pile.

[0039] In this step, the driving angle of the wood piles is 45-60 degrees, the driving depth is 1 / 3-1 / 2 of the length of the wood piles, and the interval between two adjacent wood piles is 2.5-3m. The purpose of driving the wood piles is to protect the wave-breaking dike.

[0040] An eco-bag is fixed on each wooden stake. The size of the eco-bag is 40cm×80cm. The weight of each eco-bag is 10-12kg, and the eco-bag is located below the lake surface.

[0041] The preparation method of the eco-bag is as follows:

[0042] (1) adding biochar to a sodium hydroxide solution, heating and stirring, and then filtering, washing, and drying to obtain alkali-activated biochar;

[0043] (2) dispersing the alkali-activated biochar in deionized water, then adding carboxymethyl chitosan and epichlorohydrin thereto, stirring for reaction, and after the reaction is completed, filtering, washing, and drying to obtain modified biochar;

[0044] (3) immersing the modified biochar in a calcium salt solution to chelate calcium ions, then adding the modified biochar with chelated calcium ions to a mixed aqueous solution of calcium nitrate and diammonium phosphate, heating the mixture for reaction, and after the reaction is completed, filtering, washing, and drying the mixture to obtain biochar-loaded hydroxyapatite;

[0045] (4) The biochar-loaded hydroxyapatite and the composite microbial powder are mixed evenly to obtain a mixture, and then the mixture is added to a mixed aqueous solution of sodium alginate and gelatin, shaken and mixed for 24-48 hours, and centrifuged, washed, and dried to obtain gel particles;

[0046] (5) Put the gel particles into a bag made of polypropylene and seal it to obtain an eco-bag.

[0047] Specifically, in step (1), the temperature for heating and stirring treatment is 40-60°C, for example, 40°C, 45°C, 50°C, 55°C, 60°C can be selected; the time for heating and stirring treatment is 2-5h, for example, 2h, 3h, 4h, 5h can be selected, but it is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0048] Specifically, in step (2), the mass ratio of alkali-activated biochar, carboxymethyl chitosan and epichlorohydrin is 10-15:5-8:4-6.

[0049] Specifically, in step (2), the stirring reaction temperature is 60-80°C, for example, 60°C, 65°C, 70°C, 75°C, 80°C can be selected; the stirring reaction time is 3-5h, for example, 3h, 3.5h, 4h, 4.5h, 5h can be selected, but it is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0050] Specifically, in step (3), the dosage ratio of modified biochar and calcium salt solution is 1g:5-15mL, for example, 1g:5mL, 1g:8mL, 1g:10mL, 1g:12mL, 1g:15mL can be selected; the solubility of the calcium salt solution is 10-15mmol / L, for example, 10mmol / L, 11mmol / L, 12mmol / L, 13mmol / L, 14mmol / L, 15mmol / L can be selected; but it is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0051] More specifically, the calcium salt solution is a soluble calcium salt solution, for example, a calcium nitrate solution or a calcium chloride solution.

[0052] Specifically, in step (3), the dosage ratio of the modified biochar with chelated calcium ions to the mixed aqueous solution is 1g:5-15mL, for example, 1g:5mL, 1g:6mL, 1g:8mL, 1g:10mL, 1g:12mL, 1g:15mL can be selected, the concentration of diammonium hydrogen phosphate in the mixed aqueous solution is 3-5mmol / L, for example, 3mmol / L, 3.5mmol / L, 4mmol / L, 4.5mmol / L, 5mmol / L can be selected; the molar ratio of calcium nitrate to diammonium hydrogen phosphate is 1.5-2:1, for example, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, 2:1 can be selected; but it is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0053] Specifically, in step (3), the temperature of the heating reaction is 70-85°C, for example, 70°C, 75°C, 80°C, 85°C can be selected; the time of the heating reaction is 48-72h, for example, 48h, 54h, 60h, 66h, 72h can be selected; but it is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0054] Specifically, in step (4), the mass ratio of biochar-loaded hydroxyapatite to the composite microbial powder is 10-15:1-3, for example, 10:1, 10:2, 10:3, 12:1, 12:2, 12:3, 15:1, 15:2, 15:3 can be selected; wherein the composite microbial powder is composed of putrefactive Shewanella powder and Bacillus subtilis powder, the mass ratio of putrefactive Shewanella powder to Bacillus subtilis powder is 1-2:1-2, and the number of viable bacteria in the putrefactive Shewanella powder and the Bacillus subtilis powder is not less than 1.0×10 8 cfu / g.

[0055] Specifically, in step (4), the dosage ratio of the mixture to the mixed aqueous solution is 2-4 g:100 mL, for example, 2 g:100 mL, 2.5 g:100 mL, 3 g:100 mL, 3.5 g:100 mL, 4 g:100 mL can be selected, and the mass fraction of sodium alginate in the mixed aqueous solution is 3-6%, and the mass fraction of gelatin is 1-2%.

[0056] S3. A steel column wave-breaking net is arranged 8-10m outside the wave-breaking dike. The steel column wave-breaking net includes a number of channel steels arranged along the river channel, with the interval between two adjacent channel steels being 2.5-3m. The wave-breaking net is installed on the channel steel, and a buoy is arranged on the wave-breaking net.

[0057] In this step, the selected channel steel is a 3.5m long No. 8 channel steel, which is driven into the lake bottom 1m away, with an interval of 2.5-3m between two adjacent channel steels, and a wave-breaking net is installed on the channel steel. The wave-breaking net is made of nylon net, and the bottom of the wave-breaking net is more than 50cm away from the lake bottom, allowing fish to enter and exit freely; a buoy is provided on the wave-breaking net, which floats on the water surface and is used to tow the wave-breaking net.

[0058] In this step, due to the strong winds and high waves in medium and large lakes and reservoirs, which can reach more than 2 meters, the newly repaired embankments and wave-breaking dikes are easily damaged by the erosion of waves. Even the newly built embankments are in danger of being washed away, and all kinds of planted aquatic grasses and aquatic plants will be destroyed. By establishing a steel column wave-breaking net, the wind and waves can be effectively reduced.

[0059] S4. Establish an ecological restoration wetland area between the lake bank slope and the wave-breaking dike and plant different aquatic plants.

[0060] In this step, native plants are preferred in plant configuration. Native plants adapt to the local natural environment for a long time, and they will produce convergent adaptation to environmental conditions in terms of physiology, structure, external morphology, etc. Native plants are also the species that can best adapt to local climatic conditions. Therefore, the selection of native plants can fully adapt to local environmental conditions, and can quickly build a group to achieve the purpose of restoration and reconstruction. The priority selection of native plants can also reduce the use of alien plants and reduce the ecological risk of alien plant invasion. Different plants have inconsistent growth cycles. In order to meet the requirements of waterfowl for food and habitat, the types, quantity, feeding habits and habitat habits of waterfowl in this area must be fully considered when configuring aquatic plants in habitats. The aquatic plant species that waterfowl like to eat and the emergent or wet plant species that can provide safe shelter have become the target of restoration and reconstruction. At the same time, according to the characteristics of the strip distribution of wetland vegetation and the adaptation characteristics of different ecotype plants to the hydrological environment, wet plants, emergent plants, floating leaf root plants and submerged plants are configured in suitable areas to serve the wetland ecological landscape.

[0061] The present invention will be further described below by means of specific examples.

[0062] The biochar used in the following examples and comparative examples is corn straw biochar.

[0063] Example 1

[0064] A wave-breaking lake wetland ecological restoration method comprises the following steps:

[0065] S1. Build a wave-breaking embankment at the bottom of the lake bank slope. The width of the wave-breaking embankment is 2m, the height is 1.5m, and the length is 100m. Duckweed and spike foxtail algae are planted on the wave-breaking embankment. The planting density of duckweed is 20 plants / m 2 The planting density of spike foxtail algae is 20 plants / m 2 ;

[0066] S2. Drive 3m long wooden piles obliquely into the lake bank slope, with the angle between the wooden piles and the horizontal plane being 45° and the driving depth of the wooden piles being 1m. The wooden piles are arranged along the river channel, with the interval between two adjacent wooden piles being 3m. There are 33 wooden piles, and the wooden piles are located above the wave-breaking dike. An eco-bag is fixed on each wooden pile. The size of the eco-bag is 40cm×80cm, and the weight of each eco-bag is 10kg. The eco-bag is located below the lake surface.

[0067] The preparation method of the eco-bag is as follows:

[0068] (1) 10 g of biochar was added to 100 mL of 1 mol / L sodium hydroxide solution, heated and stirred at 60 °C for 3 h, and then filtered, washed, and dried to obtain alkali-activated biochar;

[0069] (2) 12 g of alkali-activated biochar was dispersed in 100 mL of deionized water, and then 6 g of carboxymethyl chitosan and 5 g of epichlorohydrin were added thereto, and the mixture was stirred and reacted at 80 °C for 3 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain modified biochar;

[0070] (3) Immerse 10 g of modified biochar in 100 mL of 10 mmol / L calcium nitrate solution for 2 h to chelate calcium ions, then add 10 g of modified biochar with chelated calcium ions to 100 mL of a mixed aqueous solution containing calcium nitrate and diammonium hydrogen phosphate, wherein the concentration of diammonium hydrogen phosphate in the mixed aqueous solution is 4 mmol / L, and the molar ratio of calcium nitrate to diammonium hydrogen phosphate is 1.6:1. Heat the mixture at 75 °C for 60 h. After the reaction is completed, filter, wash, and dry to obtain biochar-loaded hydroxyapatite.

[0071] (4) 10 g of biochar loaded with hydroxyapatite and 2 g of composite microbial powder were mixed evenly, wherein the composite microbial powder consisted of Shewanella putrefaciens powder and Bacillus subtilis powder in a mass ratio of 1:1, and the number of viable bacteria of the Shewanella putrefaciens powder was 1.0 × 10 8 cfu / g, the number of viable bacteria of Bacillus subtilis powder is 1.0×10 8 cfu / g, and obtain a mixture, then add 2g of the mixture into 100mL of a mixed aqueous solution of sodium alginate and gelatin, wherein the mass fraction of sodium alginate in the mixed aqueous solution is 5%, and the mass fraction of gelatin is 1%, and shake and mix for 24h, and obtain gel particles after centrifugation, washing, and drying;

[0072] (5) The gel particles are placed in a bag made of polypropylene with a size of 40 cm×80 cm and the bag is sealed to obtain an eco-bag.

[0073] S3. A steel column wave-proof net is arranged 10m away from the wave-proof dike. The steel column wave-proof net includes channel steels arranged along the river channel. The position of the channel steels corresponds to the wooden piles. The selected channel steels are 3.5m long No. 8 channel steels. The channel steels are driven 1m into the lake bottom. The interval between two adjacent channel steels is 3m. A wave-proof net is installed on the channel steel. The wave-proof net is made of nylon net. The bottom of the wave-proof net is 50cm away from the lake bottom, allowing fish to enter and exit freely. A water surface float is set on the wave-proof net;

[0074] S4. Establish an ecological restoration wetland area between the lake bank slope and the wave-breaking levee, plant different aquatic plants, and plant submerged plants and emergent plants from bottom to top along the lake bank slope. The submerged plants are Vallisneria and Potamogeton. The planting density of Vallisneria is 20 plants / m 2 The planting density of Potamogeton chinensis is 20 plants / m 2 The emergent plants are reed and southern reed, and the planting density of reed is 15 plants / m 2The planting density of Nandi is 15 plants / m 2 At the same time, water lilies and Hydrilla verticillata are planted between the wave-breaking dike and the steel column wave-breaking net. The planting density of water lilies is 2 plants / m 2 The planting density of Hydrilla verticillata is 20 plants / m 2 .

[0075] Example 2

[0076] A wave-breaking lake wetland ecological restoration method comprises the following steps:

[0077] S1. Build a wave-breaking embankment at the bottom of the lake bank slope. The width of the wave-breaking embankment is 2m, the height is 1.5m, and the length is 100m. Duckweed and spike foxtail algae are planted on the wave-breaking embankment. The planting density of duckweed is 20 plants / m 2 The planting density of spike foxtail algae is 20 plants / m 2 ;

[0078] S2. Drive 3m long wooden piles obliquely into the lake bank slope, with the angle between the wooden piles and the horizontal plane being 45° and the driving depth of the wooden piles being 1m. The wooden piles are arranged along the river channel, with the interval between two adjacent wooden piles being 3m. There are 33 wooden piles, and the wooden piles are located above the wave-breaking dike. An eco-bag is fixed on each wooden pile. The size of the eco-bag is 40cm×80cm, and the weight of each eco-bag is 12kg. The eco-bag is located below the lake surface.

[0079] The preparation method of the eco-bag is as follows:

[0080] (1) 10 g of biochar was added to 100 mL of 1 mol / L sodium hydroxide solution, heated and stirred at 40 °C for 5 h, and then filtered, washed, and dried to obtain alkali-activated biochar;

[0081] (2) Dispersing 10 g of alkali-activated biochar in 100 mL of deionized water, then adding 5 g of carboxymethyl chitosan and 4 g of epichlorohydrin, stirring and reacting at 60 ° C for 5 h, after the reaction is completed, filtering, washing, and drying to obtain modified biochar;

[0082] (3) Immerse 10 g of modified biochar in 100 mL of 15 mmol / L calcium nitrate solution for 2 h to chelate calcium ions, then add 10 g of modified biochar with chelated calcium ions to 100 mL of a mixed aqueous solution containing calcium nitrate and diammonium hydrogen phosphate, wherein the concentration of diammonium hydrogen phosphate in the mixed aqueous solution is 5 mmol / L, and the molar ratio of calcium nitrate to diammonium hydrogen phosphate is 1.5:1. Heat the mixture at 70 °C for 72 h. After the reaction is completed, filter, wash, and dry to obtain biochar-loaded hydroxyapatite.

[0083] (4) 10 g of biochar loaded with hydroxyapatite and 1 g of composite microbial powder were mixed evenly, wherein the composite microbial powder consisted of Shewanella putrefaciens powder and Bacillus subtilis powder in a mass ratio of 1:1, and the number of viable bacteria of the Shewanella putrefaciens powder was 1.0 × 10 8 cfu / g, the number of viable bacteria of Bacillus subtilis powder is 1.0×10 8 cfu / g, a mixture is obtained, and then 4g of the mixture is added to 100mL of a mixed aqueous solution of sodium alginate and gelatin, wherein the mass fraction of sodium alginate in the mixed aqueous solution is 3%, and the mass fraction of gelatin is 2%, and the mixture is shaken and mixed for 24h, and gel particles are obtained after centrifugation, washing and drying;

[0084] (5) The gel particles are placed in a bag made of polypropylene with a size of 40 cm×80 cm and the bag is sealed to obtain an eco-bag.

[0085] S3. A steel column wave-proof net is arranged 10m away from the wave-proof dike. The steel column wave-proof net includes channel steels arranged along the river channel. The position of the channel steels corresponds to the wooden piles. The selected channel steels are 3.5m long No. 8 channel steels. The channel steels are driven 1m into the lake bottom. The interval between two adjacent channel steels is 3m. A wave-proof net is installed on the channel steel. The wave-proof net is made of nylon net. The bottom of the wave-proof net is 50cm away from the lake bottom, allowing fish to enter and exit freely. A water surface float is set on the wave-proof net;

[0086] S4. Establish an ecological restoration wetland area between the lake bank slope and the wave-breaking levee, plant different aquatic plants, and plant submerged plants and emergent plants from bottom to top along the lake bank slope. The submerged plants are Vallisneria and Potamogeton. The planting density of Vallisneria is 20 plants / m 2 The planting density of Potamogeton chinensis is 20 plants / m 2 The emergent plants are reed and southern reed, and the planting density of reed is 15 plants / m 2 The planting density of Nandi is 15 plants / m 2 At the same time, water lilies and Hydrilla verticillata are planted between the wave-breaking dike and the steel column wave-breaking net. The planting density of water lilies is 2 plants / m 2 The planting density of Hydrilla verticillata is 20 plants / m 2 .

[0087] Example 3

[0088] A wave-breaking lake wetland ecological restoration method comprises the following steps:

[0089] S1. Build a wave-breaking embankment at the bottom of the lake bank slope. The width of the wave-breaking embankment is 2m, the height is 1.5m, and the length is 100m. Dermatophytes and Vallisneria are planted on the wave-breaking embankment. The planting density of Dermatophytes is 20 plants / m 2 The planting density of Vallisneria is 20 plants / m 2;

[0090] S2. Drive 3m long wooden piles obliquely into the lake bank slope, with the angle between the wooden piles and the horizontal plane being 45° and the driving depth of the wooden piles being 1m. The wooden piles are arranged along the river channel, with the interval between two adjacent wooden piles being 3m. There are 33 wooden piles, and the wooden piles are located above the wave-breaking dike. An eco-bag is fixed on each wooden pile. The size of the eco-bag is 40cm×80cm, and the weight of each eco-bag is 10kg. The eco-bag is located below the lake surface.

[0091] The preparation method of the eco-bag is as follows:

[0092] (1) 10 g of biochar was added to 100 mL of 1 mol / L sodium hydroxide solution, heated and stirred at 60 °C for 2 h, and then filtered, washed, and dried to obtain alkali-activated biochar;

[0093] (2) 15 g of alkali-activated biochar was dispersed in 100 mL of deionized water, and then 8 g of carboxymethyl chitosan and 6 g of epichlorohydrin were added thereto, and the mixture was stirred and reacted at 80 °C for 3 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain modified biochar;

[0094] (3) Immerse 10 g of modified biochar in 100 mL of 12 mmol / L calcium nitrate solution for 2 h to chelate calcium ions, then add 10 g of modified biochar with chelated calcium ions into 100 mL of a mixed aqueous solution containing calcium nitrate and diammonium hydrogen phosphate, wherein the concentration of diammonium hydrogen phosphate in the mixed aqueous solution is 3 mmol / L, and the molar ratio of calcium nitrate to diammonium hydrogen phosphate is 2:1. Heat the mixture at 85 °C for 48 h. After the reaction is completed, filter, wash, and dry to obtain biochar-loaded hydroxyapatite.

[0095] (4) 10 g of biochar loaded with hydroxyapatite and 3 g of composite microbial powder were evenly mixed, wherein the composite microbial powder consisted of Shewanella putrefaciens powder and Bacillus subtilis powder in a mass ratio of 2:1, and the number of viable bacteria of the Shewanella putrefaciens powder was 1.0 × 10 8 cfu / g, the number of viable bacteria of Bacillus subtilis powder is 1.0×10 8 cfu / g, and obtain a mixture, then add 3g of the mixture into 100mL of a mixed aqueous solution of sodium alginate and gelatin, wherein the mass fraction of sodium alginate in the mixed aqueous solution is 4% and the mass fraction of gelatin is 1%, shake and mix for 24h, and obtain gel particles after centrifugation, washing and drying;

[0096] (5) The gel particles are placed in a bag made of polypropylene with a size of 40 cm×80 cm and the bag is sealed to obtain an eco-bag.

[0097] S3. A steel column wave-proof net is arranged 10m away from the wave-proof dike. The steel column wave-proof net includes channel steels arranged along the river channel. The position of the channel steels corresponds to the wooden piles. The selected channel steels are 3.5m long No. 8 channel steels. The channel steels are driven 1m into the lake bottom. The interval between two adjacent channel steels is 3m. A wave-proof net is installed on the channel steel. The wave-proof net is made of nylon net. The bottom of the wave-proof net is 50cm away from the lake bottom, allowing fish to enter and exit freely. A water surface float is set on the wave-proof net;

[0098] S4. Establish an ecological restoration wetland area between the lake bank slope and the wave-breaking levee, plant different aquatic plants, and plant submerged plants and emergent plants from bottom to top along the lake bank slope. The submerged plants are Vallisneria and Potamogeton. The planting density of Vallisneria is 25 plants / m 2 The planting density of Potamogeton edulis is 25 plants / m 2 The emergent plants are reed and southern reed, and the planting density of reed is 15 plants / m 2 The planting density of Nandi is 15 plants / m 2 At the same time, water lilies and Hydrilla verticillata are planted between the wave-breaking dike and the steel column wave-breaking net. The planting density of water lilies is 2 plants / m 2 The planting density of Hydrilla verticillata is 20 plants / m 2 .

[0099] Comparative Example 1

[0100] A wave-breaking lake wetland ecological restoration method comprises the following steps:

[0101] S1. Build a wave-breaking embankment at the bottom of the lake bank slope. The width of the wave-breaking embankment is 2m, the height is 1.5m, and the length is 100m. Duckweed and spike foxtail algae are planted on the wave-breaking embankment. The planting density of duckweed is 20 plants / m 2 The planting density of spike foxtail algae is 20 plants / m 2 ;

[0102] S2. Drive 3m long wooden piles obliquely into the lake bank slope, with the angle between the wooden piles and the horizontal plane being 45° and the driving depth of the wooden piles being 1m. The wooden piles are arranged along the river channel, with the interval between two adjacent wooden piles being 3m. There are 33 wooden piles, and the wooden piles are located above the wave-breaking dike. An eco-bag is fixed on each wooden pile. The size of the eco-bag is 40cm×80cm, and the weight of each eco-bag is 10kg. The eco-bag is located below the lake surface.

[0103] The preparation method of the eco-bag is as follows:

[0104] 10g of biochar and 2g of composite microbial powder were mixed evenly, wherein the composite microbial powder consisted of Shewanella putrefaciens powder and Bacillus subtilis powder in a mass ratio of 1:1, and the number of viable bacteria of Shewanella putrefaciens powder was 1.0×10 8cfu / g, the number of viable bacteria of Bacillus subtilis powder is 1.0×10 8 cfu / g, and obtain a mixture, then add 2g of the mixture into 100mL of a mixed aqueous solution of sodium alginate and gelatin, wherein the mass fraction of sodium alginate in the mixed aqueous solution is 5%, and the mass fraction of gelatin is 1%, and shake and mix for 24h, and obtain gel particles after centrifugation, washing, and drying;

[0105] The gel particles were placed in a bag made of polypropylene with a size of 40 cm×80 cm, and the bag was sealed to obtain an eco-bag.

[0106] S3. A steel column wave-proof net is arranged 10m away from the wave-proof dike. The steel column wave-proof net includes channel steels arranged along the river channel. The position of the channel steels corresponds to the wooden piles. The selected channel steels are 3.5m long No. 8 channel steels. The channel steels are driven 1m into the lake bottom. The interval between two adjacent channel steels is 3m. A wave-proof net is installed on the channel steel. The wave-proof net is made of nylon net. The bottom of the wave-proof net is 50cm away from the lake bottom, allowing fish to enter and exit freely. A water surface float is set on the wave-proof net;

[0107] S4. Establish an ecological restoration wetland area between the lake bank slope and the wave-breaking levee, plant different aquatic plants, and plant submerged plants and emergent plants from bottom to top along the lake bank slope. The submerged plants are Vallisneria and Potamogeton. The planting density of Vallisneria is 20 plants / m 2 The planting density of Potamogeton chinensis is 20 plants / m 2 The emergent plants are reed and southern reed, and the planting density of reed is 15 plants / m 2 The planting density of Nandi is 15 plants / m 2 At the same time, water lilies and Hydrilla verticillata are planted between the wave-breaking dike and the steel column wave-breaking net. The planting density of water lilies is 2 plants / m 2 The planting density of Hydrilla verticillata is 20 plants / m 2 .

[0108] Compared with Example 1, in Comparative Example 1, the biochar was not modified, and the biochar was directly blended with the composite microbial powder.

[0109] The following table shows the changes in the content of pollutants in the lake water body before and after 3 months of ecological restoration in Example 1 and Comparative Example 1:

[0110]

[0111] It can be seen from the table that the wave-breaking lake and reservoir wetland ecological restoration method provided by the present invention can significantly reduce the total nitrogen, total phosphorus and ammonia nitrogen contents in lake and reservoir water, and the ecological restoration effect is very significant, which has good application prospects.

[0112] Finally, it should be noted that the above embodiments do not limit the present invention in any form. For those skilled in the art, some modifications and improvements can be made to the present invention. Therefore, any modification or improvement made without departing from the spirit of the present invention belongs to the scope of protection claimed in the present invention.

Claims

1. A wave-breaking lake wetland ecological restoration method, characterized in that: The steps include: S1. Build a wave-breaking embankment at the bottom of the lake bank slope; S2. Drive wooden piles obliquely into the lake bank slope to a depth of 1 / 3-1 / 2 of the length of the wooden piles. The wooden piles are arranged along the river channel and located above the wave-breaking dike. The interval between two adjacent wooden piles is 2.5-3m. An eco-bag is fixed on each wooden pile, and the eco-bag is located below the lake surface. S3, a steel column wave-breaking net is arranged 8-10m outside the wave-breaking dike, the steel column wave-breaking net comprises a number of channel steels arranged along the river channel, the interval between two adjacent channel steels is 2.5-3m, the channel steels are equipped with a wave-breaking net, and a buoy is arranged on the wave-breaking net; S4. Establish an ecological restoration wetland area between the lake bank slope and the wave-breaking dike and plant different aquatic plants.

2. The wave-breaking lake wetland ecological restoration method according to claim 1 is characterized in that: In step S2, the preparation method of the eco-bag is as follows: (1) adding biochar to a sodium hydroxide solution, heating and stirring, and then filtering, washing, and drying to obtain alkali-activated biochar; (2) dispersing the alkali-activated biochar in deionized water, then adding carboxymethyl chitosan and epichlorohydrin thereto, stirring to react, and after the reaction is completed, filtering, washing, and drying to obtain modified biochar; (3) immersing the modified biochar in a calcium salt solution to chelate calcium ions, then adding the modified biochar with chelated calcium ions to a mixed aqueous solution of calcium nitrate and diammonium phosphate, heating the mixture for reaction, and after the reaction is completed, filtering, washing, and drying to obtain biochar-loaded hydroxyapatite; (4) The biochar-loaded hydroxyapatite and the composite microbial powder are mixed evenly to obtain a mixture, and then the mixture is added to a mixed aqueous solution of sodium alginate and gelatin, and the mixture is shaken and mixed for 24-48 hours, and the gel particles are obtained by centrifugation, washing, and drying; (5) Place the gel particles into a bag made of polypropylene and seal the bag to obtain an eco-bag.

3. The method for ecological restoration of lake and reservoir wetlands according to claim 2, characterized in that: In step (1), the temperature of the heating and stirring treatment is 40-60° C., and the time of the heating and stirring treatment is 2-5 h.

4. The method for ecological restoration of lake and reservoir wetlands according to claim 2, characterized in that: In step (2), the mass ratio of alkali-activated biochar, carboxymethyl chitosan and epichlorohydrin is 10-15:5-8:4-6.

5. The wave-breaking lake wetland ecological restoration method according to claim 2 is characterized in that: In step (2), the stirring reaction temperature is 60-80° C., and the stirring reaction time is 3-5 h.

6. The wave-breaking lake wetland ecological restoration method according to claim 2 is characterized in that: In step (3), the solubility of the calcium salt solution is 10-15 mmol / L, the concentration of diammonium hydrogen phosphate in the mixed aqueous solution is 3-5 mmol / L, and the molar ratio of calcium nitrate to diammonium hydrogen phosphate is 1.5-2:

1.

7. The wave-breaking lake wetland ecological restoration method according to claim 2 is characterized in that: In step (3), the heating reaction temperature is 70-85°C and the heating reaction time is 48-72h.

8. The wave-breaking lake wetland ecological restoration method according to claim 2 is characterized in that: In step (4), the mass ratio of biochar-loaded hydroxyapatite to composite microbial powder is 10-15:1-3, wherein the composite microbial powder is composed of Shewanella putrefaciens powder and Bacillus subtilis powder, the mass ratio of Shewanella putrefaciens powder to Bacillus subtilis powder is 1-2:1-2, and the number of viable bacteria in Shewanella putrefaciens powder and Bacillus subtilis powder is not less than 1.0×10 8 cfu / g.

9. The wave-breaking lake wetland ecological restoration method according to claim 2 is characterized in that: In step (4), the ratio of the mixed material to the mixed aqueous solution is 2-4 g: 100 mL.

10. The wave-breaking lake wetland ecological restoration method according to claim 2 is characterized in that: In step (4), the mass fraction of sodium alginate in the mixed aqueous solution is 3-6%, and the mass fraction of gelatin is 1-2%.

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