Gradient removal method for suspended solids in water body in three-dimensional polyculture of fishes with different feeding habits

Abstract

The invention discloses a gradient removal method for suspended solids in a water body for three-dimensional polyculture of fishes with different feeding habituals, which belongs to the technical field of aquaculture and comprises the following steps: respectively mounting different floating nets on a water surface layer and a middle layer of an aquaculture water area; putting filter-feeding fishes in the water surface layer of the culture water area, putting scraping-feeding fishes in the middle layer of the culture water area, and putting benthic organisms in the bottom layer of the culture water area; floating feed is put 2-3 times every day on the water surface layer of the aquaculture water area, a 40% fermented material and 60% sinking material mixed feeding mode is adopted on the bottom layer of the aquaculture water area, feeding is conducted at night, and residual feed is cleaned and recycled once every day; the concentration of the suspended particulate matters and the turbidity of the water body are monitored in real time, when the concentration of the suspended particulate matters is larger than a threshold value, the proportion of scraping-feeding fishes is increased, the proportion of benthic organisms is reduced, and when the concentration of the suspended particulate matters is smaller than the threshold value, the proportion of filter-feeding fishes is increased. Meanwhile, the stability problem of the polyculture system is solved through a dynamic proportion regulation mechanism.

Description

Technical Field

[0001] The invention relates to the technical field of aquaculture, and in particular to a method for gradient removal of suspended matter in water bodies for three-dimensional mixed culture of fish with different feeding habits. Background Art

[0002] Factory farming has become the mainstream aquaculture model in my country's aquaculture industry. During this aquaculture process, the accumulation of suspended particulate matter (TSS) from leftover bait and feces can lead to eutrophication, pathogen breeding, and economic losses. Existing technologies for removing suspended particulate matter include physical and biological methods. Physical precipitation only removes 30-60% of TSS from wastewater with high suspended matter concentrations. According to a study titled "A Comparative Study on the Purification Effects of Three Species of Tidal Flat Shellfish on the Tailwater of Litopenaeus vannamei," stocking the tailwater with 20 tilapia per cubic meter of tilapia reduced suspended particulate matter concentrations by 46.5%. A study titled "Experimental Study on the Purification of Intensive Pond Water by Odontodontia dorsi" reported that after ten hours of stocking intensive ponds with Odontodontia dorsi, suspended particulate matter removal rates reached 47.97%-91.87%. In a study titled "Research Progress in Pond Aquaculture Wastewater Treatment Technologies," Song Wei et al. reported that a mixed culture system of silver carp and bighead carp with a density of 40 g / m3 can increase water transparency from 30 cm to 80 cm.

[0003] The sedimentation tanks required for physical methods occupy a large area, microfiltration machines consume a lot of energy and cannot decompose organic matter. Traditional single filter-feeding fish (such as silver carp and bighead carp) can only remove suspended particles with a particle size greater than 50 microns, and are less effective in removing fine particles with a particle size less than 30 microns and bottom mud. Single shellfish filter-feeding (such as oysters) easily consumes plankton and disrupts the ecological balance. Existing technology cannot efficiently remove suspended matter of different particle sizes in aquaculture water. Therefore, it is necessary to design a gradient removal method for suspended matter in water bodies for three-dimensional mixed culture of fish with different feeding habits. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for gradient removal of suspended matter in water bodies for three-dimensional mixed culture of fish with different feeding habits, so as to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solution: a method for gradient removal of suspended matter in water bodies for three-dimensional polyculture of fish with different feeding habits, comprising the following steps:

[0006] S1. Install different floating nets in the surface layer and middle layer of the aquaculture waters;

[0007] S2. Stock the surface layer of the aquaculture waters with filter-feeding fish, the middle layer with scraper-feeding fish, and the bottom layer with benthic organisms. Use floating nets in the surface layer and the middle layer of the aquaculture waters to confine the filter-feeding fish and scraper-feeding fish to the target water layers, respectively.

[0008] S3. Floating feed is added to the surface layer of the aquaculture waters 2-3 times a day, and a mixed feed of 40% fermented feed and 60% sinking feed is added to the bottom of the aquaculture waters. Feeding is carried out at night, and the remaining bait is cleaned and recovered once a day for fermentation feed reproduction;

[0009] S4. Monitor the concentration of suspended particulate matter and water turbidity in real time. When the concentration of suspended particulate matter is greater than the threshold, increase the proportion of scraping fish and reduce the proportion of benthic organisms. When the concentration of suspended particulate matter is less than the threshold, increase the proportion of filter-feeding fish.

[0010] In a further embodiment, in step S1, the water surface layer uses a high-strength polyethylene net with a mesh diameter of 5 cm, and the high-strength polyethylene net is installed 0.5 m below the water surface to limit the activity range of filter-feeding fish. The middle layer uses a nylon woven net with a mesh diameter of 2-3 cm, and the nylon woven net is installed 1 m below the water surface. The nylon woven net intercepts algae for scraping fish to eat, while ensuring that the fish are stratified.

[0011] In a further embodiment, in step S2, the filter-feeding fish are used to remove floating particles with a particle size greater than 50 microns in the aquaculture waters, the scraping fish are used to remove attached algae with a particle size of 30-50 microns, and the benthic organisms are used to remove debris with a particle size of 30-50 microns.

[0012] In a further embodiment, in step S2, the stocking density ratios of the filter-feeding fish, scraper-feeding fish and benthic organisms are 40%, 35% and 25% respectively.

[0013] In a further embodiment, in step S2, the filter-feeding fish is silver carp, the scraping fish is bream, and the benthic organisms are loach and river snail.

[0014] In a further embodiment, in step S2, the amount of silver carp released is 800 silver carp with a specification of 300g / tail per mu, the amount of bream released is 700 bream with a specification of 200g / tail per mu, the amount of loach released is 500 per mu, and the amount of snail released is 50kg per mu.

[0015] In a further embodiment, in step S4, when the suspended particulate matter concentration is greater than 200 mg / L, the proportion of scraping fish is increased to 40% and the proportion of benthic organisms is reduced to 20%; when the suspended particulate matter concentration is less than 200 mg / L, the proportion of filter-feeding fish is increased to 50%.

[0016] In a further embodiment, in step S4, every 1000m 3A NIR sensor and a buoy station are set up in the water body to form a triangular detection network for real-time monitoring of suspended particulate matter concentration and water turbidity.

[0017] In a further embodiment, in step S3, the protein content of the floating feed is 28%, and the daily feeding amount of the floating feed is 2-3% of the total body weight of the filter-feeding fish;

[0018] The fermentation material is Bacillus, and the amount of Bacillus is 10 6 CFU / g, the sinking material is a mixture of soybean meal base material and 2% bentonite, with a density of 1.2-1.3g / cm3, and the feeding amount of the 40% fermentation material and 60% sinking material is 1.5-2% of the total amount of benthic organisms.

[0019] In a further embodiment, in step S4, the biomass density is analyzed using a near-infrared spectrometer, and the ratio of corresponding fish and benthic organisms is adjusted by releasing pre-cultivated fish species and transferring adult fish and benthic organisms to temporary holding ponds.

[0020] Compared with the existing technology, the beneficial effects achieved by the present invention are: the present invention combines the complementary feeding habits of fish and the vertical space of the aquaculture system, establishes a suspended particulate matter particle size-fish feeding habit matching model, realizes the precise classification and removal of particulate matter, and solves the stability problem of the polyculture system through a dynamic proportion control mechanism, breaking through the bottleneck of traditional polyculture technology, and providing an efficient ecological solution for factory aquaculture pollution control. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0022] In the following description, numerous specific details are provided to provide a more thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without one or more of these details. In other instances, certain technical features well known in the art are not described to avoid confusion with the present invention.

[0023] See also Figure 1 The present invention provides a technical solution: a method for gradient removal of suspended matter in water bodies for three-dimensional mixed culture of fish with different feeding habits, comprising the following steps:

[0024] S1. Install different floating nets in the surface layer and middle layer of the aquaculture waters;

[0025] S2. Stock the surface layer of the aquaculture waters with filter-feeding fish, the middle layer with scraper-feeding fish, and the bottom layer with benthic organisms. Use floating nets in the surface layer and the middle layer of the aquaculture waters to confine the filter-feeding fish and scraper-feeding fish to the target water layers, respectively.

[0026] S3. Floating feed is added to the surface layer of the aquaculture waters 2-3 times a day, and a mixed feed of 40% fermented feed and 60% sinking feed is added to the bottom of the aquaculture waters. Feeding is carried out at night, and the remaining bait is cleaned and recovered once a day for fermentation feed reproduction;

[0027] S4. Monitor the concentration of suspended particulate matter and water turbidity in real time. When the concentration of suspended particulate matter is greater than the threshold, increase the proportion of scraping fish and reduce the proportion of benthic organisms. When the concentration of suspended particulate matter is less than the threshold, increase the proportion of filter-feeding fish.

[0028] Through the above technical solution, filter-feeding fish remove particles with a size greater than 50 microns in the surface layer of the aquaculture waters, scraping fish remove algae with a size of 30-50 microns in the middle layer of the aquaculture waters, and benthic organisms remove debris with a size less than 30 microns in the bottom layer of the aquaculture waters, thereby reducing the concentration of suspended particulate matter in the aquaculture waters, preventing eutrophication of the water body, and increasing the total fish production.

[0029] In a further embodiment, in step S1, the water surface layer uses a high-strength polyethylene net with a mesh diameter of 5 cm, which is installed 0.5 m below the water surface to limit the activity range of filter-feeding fish. The middle layer uses a nylon woven net with a mesh diameter of 2-3 cm, which is installed 1 m below the water surface. The nylon woven net intercepts algae for scraping fish to eat, while ensuring that the fish are stratified.

[0030] Through the above technical solution, the activity range of silver carp is restricted by high-strength polyethylene nets, and algae are intercepted by nylon woven nets for the three-legged carp to eat, while ensuring the stratification of fish schools.

[0031] In a further embodiment, in step S2, filter-feeding fish are used to remove floating particles with a size greater than 50 microns in the aquaculture waters, scraping fish are used to remove attached algae with a size of 30-50 microns, and benthic organisms are used to remove debris with a size of 30-50 microns.

[0032] Through the above technical solution, the gradient removal of suspended particulate matter from large particles to micro-debris is achieved through the complementarity and three-dimensional polyculture of filter-feeding fish, scraping fish and benthic organisms.

[0033] In a further embodiment, in step S2, the stocking density ratios of filter-feeding fish, scraper-feeding fish and benthic organisms are 40%, 35% and 25% respectively.

[0034] Through the above technical solution, the concentration of suspended particulate matter in the aquaculture waters can be conveniently reduced by setting the density ratio of filter-feeding fish, scraping fish and benthic organisms. At the same time, through subsequent dynamic proportion regulation, the gradient removal of suspended particulate matter in the aquaculture waters can be achieved.

[0035] In a further embodiment, in step S2, the filter-feeding fish is silver carp, the scraping fish is bream, and the benthic organisms are loach and river snail.

[0036] Through the above technical solution, silver carp filters plankton and larger organic debris in the water, bream scrapes algae and organic debris, and loach and river snail remove smaller organic debris.

[0037] In a further embodiment, in step S2, the amount of silver carp released is 800 silver carp with a specification of 300g / tail per mu, the amount of bream released is 700 bream with a specification of 200g / tail per mu, the amount of loach released is 500 per mu, and the amount of snail released is 50kg per mu.

[0038] Through the above technical solution, the number of silver carp, bighead carp, loach and river snails released is reasonable according to the area of ​​the aquaculture water area, thereby improving the treatment effect of suspended particulate matter.

[0039] In a further embodiment, in step S4, when the suspended particulate matter concentration is greater than 200 mg / L, the proportion of scraping fish is increased to 40% and the proportion of benthic organisms is reduced to 20%; when the suspended particulate matter concentration is less than 200 mg / L, the proportion of filter-feeding fish is increased to 50%.

[0040] Through the above technical solution, the proportion of filter-feeding fish, scraper-feeding fish and benthic organisms is dynamically adjusted according to the change of the suspended particulate matter concentration, so as to facilitate the efficient gradient removal of suspended particulate matter in the aquaculture waters.

[0041] In a further embodiment, in step S4, every 1000m 3 A NIR sensor and a buoy station are set up in the water body to form a triangular detection network for real-time monitoring of suspended particulate matter concentration and water turbidity.

[0042] Through the above technical solution, the coordination of NIR sensors and buoy stations facilitates the subsequent dynamic proportional control of filter-feeding fish, scraper-feeding fish and benthic organisms.

[0043] In a further embodiment, in step S3, the protein content of the floating feed is 28%, and the daily feeding amount of the floating feed is 2-3% of the total body weight of the filter-feeding fish;

[0044] In step S3, the fermentation material is Bacillus, and the amount of Bacillus is 10 6CFU / g, the sinking feed is a mixture of soybean meal base and 2% bentonite, with a density of 1.2-1.3g / cm3, and the feeding amount of 40% fermented feed and 60% sinking feed is 1.5-2% of the total benthic organisms.

[0045] Through the above technical solution, the growth of fish in the aquaculture waters is ensured by the floating feed, and the normal growth of benthic organisms is ensured by the mixed feeding of Bacillus and sinking feed.

[0046] In a further embodiment, in step S4, the biomass density is analyzed using a near-infrared spectrometer, and the ratio of corresponding fish and benthic organisms is adjusted by releasing pre-cultivated fish species and transferring adult fish and benthic organisms to temporary holding ponds.

[0047] Through the above technical solution, the stocking ratio is ensured to reach the specified ratio by adjusting the biomass of corresponding fish and benthic organisms.

[0048] In this system, silver carp achieve an 85% removal rate for particles larger than 50 microns in the surface layer, bream achieve a 78% removal rate for algae between 30 and 50 microns in the middle layer, and loach and river snails achieve a 63% removal rate for debris smaller than 30 microns in the bottom layer. The average suspended particulate matter concentration of the entire system has been reduced from 210 mg / L to 90 mg / L, and total fish production has increased from 1,000 kg / mu to 1,500 kg / mu. Furthermore, this system reduces operating costs by 60% compared to mechanical filtration systems, achieving precise, size-based removal of suspended particulate matter while reducing costs.

[0049] The preferred specific embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above specific embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all fall within the scope of protection of the present invention.

Claims

1. A method for gradient removal of suspended solids in water bodies for three-dimensional polyculture of fish with different feeding habits, characterized in that: The steps include: S1. Install different floating nets in the surface layer and middle layer of the aquaculture waters; S2. Stock the surface layer of the aquaculture waters with filter-feeding fish, the middle layer with scraper-feeding fish, and the bottom layer with benthic organisms. Use floating nets in the surface layer and the middle layer of the aquaculture waters to confine the filter-feeding fish and scraper-feeding fish to the target water layers, respectively. S3. Floating feed is added to the surface layer of the aquaculture waters 2-3 times a day, and a mixed feed of 40% fermented feed and 60% sinking feed is added to the bottom of the aquaculture waters. Feeding is carried out at night, and the remaining bait is cleaned and recovered once a day for fermentation feed reproduction; S4. Monitor the concentration of suspended particulate matter and water turbidity in real time. When the concentration of suspended particulate matter is greater than the threshold, increase the proportion of scraping fish and reduce the proportion of benthic organisms. When the concentration of suspended particulate matter is less than the threshold, increase the proportion of filter-feeding fish.

2. The method for gradient removal of suspended solids in water for three-dimensional polyculture of fish with different feeding habits according to claim 1, characterized in that: In step S1, the surface layer uses a high-strength polyethylene net with a mesh diameter of 5 cm, which is installed 0.5 m below the water surface to limit the activity range of filter-feeding fish. The middle layer uses a nylon woven net with a mesh diameter of 2-3 cm, which is installed 1 m below the water surface. The nylon woven net intercepts algae for scraping fish to eat and ensures that the fish are stratified.

3. The method for gradient removal of suspended solids in water for three-dimensional polyculture of fish with different feeding habits according to claim 1, characterized in that: In step S2, the filter-feeding fish are used to remove floating particles with a particle size greater than 50 microns in the aquaculture waters, the scraping fish are used to remove attached algae with a particle size of 30-50 microns, and the benthic organisms are used to remove debris with a particle size of 30-50 microns.

4. The method for gradient removal of suspended solids in water for three-dimensional polyculture of fish with different feeding habits according to claim 1, characterized in that: In step S2, the stocking density ratios of the filter-feeding fish, scraper-feeding fish and benthic organisms are 40%, 35% and 25% respectively.

5. The method for gradient removal of suspended solids in water for three-dimensional polyculture of fish with different feeding habits according to claim 1, characterized in that: In step S2, the filter-feeding fish is silver carp, the scraping fish is bream, and the benthic organisms are loach and river snail.

6. The method for gradient removal of suspended solids in water for three-dimensional polyculture of fish with different feeding habits according to claim 5, characterized in that: In step S2, the silver carp is released in an amount of 800 silver carp with a specification of 300g / tail per mu, the black carp is released in an amount of 700 black carp with a specification of 200g / tail per mu, the loach is released in an amount of 500 per mu, and the snail is released in an amount of 50kg per mu.

7. The method for gradient removal of suspended solids in water for three-dimensional polyculture of fish with different feeding habits according to claim 1, characterized in that: In step S4, when the suspended particulate matter concentration is greater than 200 mg / L, the proportion of scraping fish is increased to 40% and the proportion of benthic organisms is reduced to 20%; when the suspended particulate matter concentration is less than 200 mg / L, the proportion of filter-feeding fish is increased to 50%.

8. The method for gradient removal of suspended solids in water for three-dimensional polyculture of fish with different feeding habits according to claim 1, characterized in that: In step S4, every 1000m 3 A NIR sensor and a buoy station are set up in the water body to form a triangular detection network for real-time monitoring of suspended particulate matter concentration and water turbidity.

9. The method for gradient removal of suspended solids in water for three-dimensional polyculture of fish with different feeding habits according to claim 1, characterized in that: In step S3, the protein content of the floating feed is 28%, and the daily feeding amount of the floating feed is 2-3% of the total body weight of the filter-feeding fish; The fermentation material is Bacillus, and the amount of Bacillus is 10 6 CFU / g, the sinking material is a mixture of soybean meal base material and 2% bentonite, with a density of 1.2-1.3g / cm3, and the feeding amount of the 40% fermentation material and 60% sinking material is 1.5-2% of the total amount of benthic organisms.

10. The method for gradient removal of suspended solids in water for three-dimensional polyculture of fish with different feeding habits according to claim 1, characterized in that: In step S4, the biomass density is analyzed using a near-infrared spectrometer, and the ratio of fish to benthic organisms is adjusted by releasing pre-cultivated fish species and transferring adult fish and benthic organisms to temporary holding ponds.

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