A shrimp, crab, mussel and fish three-dimensional ecological breeding method on large water surface by utilizing niche complementation

Abstract

The present application belongs to the technical field of shrimp, crab, shellfish and fish three-dimensional ecological aquaculture method, especially to a shrimp, crab, shellfish and fish three-dimensional ecological aquaculture method using ecological niche complementation, a salt pond in intertidal zone is selected, a culture salt pond with an area of more than 500 mu is constructed, the culture salt pond is 400-450 m wide from east to west, 850-950 m long from south to north, and 3.0-3.2 m deep, a ring ditch is excavated around the culture salt pond, a central ditch with the same direction as water inlet and outlet is excavated in the center, a shellfish bed is arranged between the ring ditch and the central ditch, and the slope ratio of water inlet to water outlet is 1.8:1.0.

Description

Technical Field

[0001] This invention belongs to the technical field of large-scale three-dimensional ecological aquaculture methods for shrimp, crab, shellfish and fish, and particularly relates to a large-scale three-dimensional ecological aquaculture method for shrimp, crab, shellfish and fish that utilizes complementary ecological niches. Background Technology

[0002] In the field of marine large-scale shrimp, crab, shellfish and fish farming, the existing model is still mainly based on single-species farming. This not only fails to make full use of the three-dimensional space of the water body and the nutrient resources of different water layers, but also easily leads to eutrophication and disease outbreaks due to the accumulation of metabolic products. The survival rate and economic benefits fluctuate greatly. The few attempts at polyculture are just simple superposition of species, without ecological niche complementarity design based on the different water layers and feeding characteristics of different species. This fails to give full play to the planktonic feeding regulation function of spotted gudgeon, the water purification function of shellfish, and the decontamination function of swimming crab. There is survival competition between species, poor ecological stability of the farming system, and the inability to achieve the dual effect of water quality self-purification and yield increase.

[0003] Meanwhile, the existing supporting technology system for aquaculture suffers from significant problems of extensiveness. There are no scientific and unified standards for the timing, density, and size of seedling release. The layout of ditches and drainage systems in aquaculture areas are not adapted to the needs of three-dimensional aquaculture. Water quality management, such as water exchange, application of microecological agents, and oxygenation strategies, lacks precision. Feeding management also fails to design differentiated plans based on the growth stages of different species and water temperature changes. Furthermore, the common three-spined swimming crab species has insufficient tolerance to low salinity and slow growth rate, resulting in low material and energy cycle efficiency of the aquaculture system, prominent problems of feed waste and water pollution, and high aquaculture costs. This makes it difficult to meet the development needs of green, ecological, efficient, and intensive aquaculture. Summary of the Invention

[0004] The purpose of this invention is to address the aforementioned technical problems by providing a method for large-scale, three-dimensional ecological aquaculture of shrimp, crabs, shellfish, and fish that utilizes complementary ecological niches.

[0005] In view of this, the present invention provides a method for large-scale three-dimensional ecological aquaculture of shrimp, crabs, shellfish and fish utilizing complementary ecological niches, comprising the following steps: Select salt-producing ponds in the intertidal zone and construct aquaculture salt ponds with an area of ​​more than 500 mu. The aquaculture salt ponds are 400m to 450m wide from east to west, 850m to 950m long from north to south, and 3.0m to 3.2m deep. Dig a ring ditch around the aquaculture salt ponds and dig a central ditch in the same direction as the water inlet and outlet. Set up shell beds between the ring ditch and the central ditch. The slope ratio of the water inlet and outlet directions is 1.8:1.0. After the harvest was completed in early December of that year, the pond water was drained. Before March of the following year, the salt pond was exposed to the sun, dredged, and cleaned and repaired. Fifteen days before water was introduced, the ring ditch, central ditch, and shell beds were disinfected with bleaching powder. At the same time, the shell beds were covered with polyethylene netting. The salt pond was separated for water inlet and outlet, and double-layered 60-mesh polyethylene netting was installed at the inlet and outlet. In early March, the water was introduced to a depth of 30cm above the surface of the shell beds. In late March, four-cornered clam and Manila clam seedlings are stocked into the shellfish beds. The four-cornered clam seedlings have an average shell length of 2cm and a stocking density of 130kg / mu to 150kg / mu. The Manila clam seedlings have an average shell length of 1.1cm and a stocking density of 190kg / mu to 210kg / mu. In mid-April, when the water temperature is ≥15℃, Chinese shrimp seedlings with a total length of 0.9cm to 1.1cm are stocked at a density of 4000 to 6000 shrimp / mu. In early May, when the water temperature is ≥18℃, swimming crab (Portunus trituberculatus) seedlings (stage II) are stocked at a density of 4000 to 6000 crabs / mu. In late June, spotted gudgeon seedlings with a length of 3cm to 4cm are stocked at a density of 400 to 600 gudgeons / mu. After releasing the shellfish larvae, gradually increase the water level to 50-60cm above the shellfish beds. Use water quality nutrients to cultivate basic food organisms, controlling the water color to a light green rich in green algae and diatoms, and the water transparency to 40-50cm. In July, raise the water level to 1.7m-2.0m above the shellfish beds and maintain it stable. Apply Bacillus and EM bacteria in June and July, and apply lactic acid bacteria and photosynthetic bacteria in August and September to regulate water quality. Start aeration in mid-July. Adjust water quality by bottom water exchange according to water temperature, and replenish fresh water promptly after heavy rain. Measure water temperature, dissolved oxygen, salinity, and transparency daily, and examine plankton microscopically every two days. Four-cornered clams and Manila clams feed on planktonic food. During the Chinese shrimp farming period, artificial compound feed is given every 5 to 7 days at a rate of 1 kg / mu to 1.5 kg / mu. Feeding begins after the release of the second-stage seedlings of swimming crabs, with fresh, smooth blue clams as the main feed and frozen small shrimp as a supplement. After the fifth stage, frozen sandworms are added. The feeding frequency and amount are adjusted according to the water temperature and growth conditions. Some Chinese shrimp are harvested before the Mid-Autumn Festival, the remaining Chinese shrimp and gudgeon are harvested in late October, and swimming crabs are harvested from late October to mid-November; clams and Manila clams are harvested from late November to early December.

[0006] Preferably, in step one, the width of the ring ditch is 10m to 12m, the distance from the salt pond dam is 1.5m to 2m, and the distance from the bottom of the pond is 40cm to 50cm; the width of the central ditch is 20m to 22m, and the distance from the bottom of the pond is 70cm to 80cm. The shell beds are divided into 6 to 8 sections, each section being 100m to 110m wide, 180m to 200m long, and 25cm to 35cm higher than the bottom of the pond. The area of ​​the shell beds accounts for 70% to 72% of the total area of ​​the salt pond. Four-cornered clams were planted on one side of the shellfish bed, while Manila clams were planted on the other side.

[0007] Preferably, in step two, the water depth is controlled at 15cm to 25cm and the bleaching powder concentration is 35g / m³ during disinfection, and the water is rinsed twice after disinfection. During the middle and later stages of aquaculture, the netting at the inlet and outlet was replaced with double-layered 40-mesh and 20-mesh polyethylene netting, respectively.

[0008] Preferably, in step one, the seedlings of four-cornered clams and Manila clams are evenly sown in the shellfish beds; Chinese shrimp larvae must be uniform, clean, vigorous, and free from specific pathogens; The seedlings of the three-spotted swimming crab (Portunus trituberculatus) in the second stage require uniform metamorphosis, vigorous activity, and good health without damage, with a size of 12,000 to 14,000 crabs / kg; The gudgeon seedlings are naturally bred and caught at sea.

[0009] Preferably, the water nutrient agent mentioned in step four is a fertilizer paste; Turn on the oxygenation equipment 2 hours before and after applying Bacillus subtilis; the oxygenation method is mechanical oxygenation by an aerator or microporous nanotube micro-aeration oxygenation, and place 2 circular nano oxygenation discs with a diameter of 60cm to 80cm per acre. The water change rule is as follows: when the average daily water temperature is ≥28℃, change the water once a day, drain the water first and then add water, draining 40cm to 50cm from the bottom each time; When the average daily water temperature is less than 28℃, change the water every 2 to 3 days, draining 20cm to 30cm from the bottom each time.

[0010] Preferably, aerators are installed every 125m along the north-south direction of Yanwangzi, at a distance of 40m from the Yanwangzi dike; Do not bottom-seed shellfish within a 25m radius of the aerator or nano-aeration disc.

[0011] Preferably, in step five, the artificial compound feed for Chinese shrimp is a special compound feed for shrimp, which is evenly spread in the ring ditch and central ditch area of ​​the salt pond when it is put in.

[0012] Preferably, the feeding parameters for the three-spined swimming crab in step five are: feeding once a day from May to June, with the feeding amount being 50% to 80% of the total weight of the three-spined swimming crab; In July, feed twice a day, once in the morning and once in the evening, with the amount of feed being 8% to 10% of the total weight; From August to October, feed twice a day, once in the morning and once in the evening, with the amount of feed being 10% to 12% of the total weight; Feed once a day starting in November, with the amount of feed being 3% to 5% of the total weight. Stop feeding when the water temperature is below 8℃.

[0013] Preferably, this also includes daily pond inspection steps: inspect the pond once each in the early morning and evening to check the feeding, growth and activity of the cultured organisms, and promptly remove uneaten feed and dead bodies from the culture water.

[0014] Preferably, in step six, Chinese shrimp and spotted gudgeon are harvested using traps or seine nets, swimming crabs are harvested using crab traps or gillnets, and four-cornered clams and Manila clams are harvested using harvesting tools; At harvest time, Chinese prawns weigh 23g-37g / tail, male swimming crabs weigh 120g-224g / each, female swimming crabs weigh 200g-315g / each, spotted gudgeon weigh 135g-200g / tail, four-cornered clams have an average shell length of ≥3.1cm, and Manila clams have an average shell length of ≥3.2cm.

[0015] The beneficial effects of this invention are as follows: This method relies on a scientific niche complementarity design to achieve three-dimensional habitat for Chinese shrimp, swimming crab "Huangxuan No. 2", four-cornered clams, Manila clams, and spotted gudgeon in different areas of the upper, lower, and bottom sediment layers of the water body, fully exploring the spatial and nutrient resource potential of the large salt flat area and constructing a complete aquaculture biological cycle chain. Through the synergistic effect of spotted gudgeon feeding on plankton to regulate primary productivity, bivalve mollusks filtering and purifying water quality, and swimming crabs removing dead and weak organisms, the accumulation of uneaten feed and metabolic products is effectively reduced, achieving self-purification regulation of the aquaculture water body. This significantly reduces the risk of eutrophication and disease outbreaks, reduces the input of water quality improvers and disease control agents, and significantly improves the ecological stability of the aquaculture system and the overall survival rate of each species.

[0016] This method, through standardized construction of aquaculture ditches and ridges, precise tiered seedling release tailored to water temperature and growth cycle, coupled with refined water quality control and differentiated feeding management, and leveraging the advantages of the low-salt-tolerant and fast-growing swimming crab "Huangxuan No. 2," synchronizes the growth rhythms of various farmed species, enhances their environmental adaptability, and significantly improves feed utilization by employing differentiated feeding strategies, reducing feed waste and aquaculture costs. Simultaneously, the method results in uniform marketable sizes and improved quality for all farmed species, leading to a significant increase in yield per unit area. This achieves simultaneous high yields of shrimp, crab, shellfish, and fish, greatly enhancing the economic benefits of large-scale aquaculture. It aligns with the green, ecological, efficient, and intensive development requirements of aquaculture and possesses significant value for large-scale promotion and application. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the salt pond of the present invention; Figure 2 This is a schematic diagram of the cross-section of the salt pond of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0019] A method for large-scale, three-dimensional ecological aquaculture of shrimp, crabs, shellfish, and fish utilizing niche complementarity includes the following steps: Construction of Salt Ponds for Aquaculture: The salt ponds are located in the intertidal zone and were originally secondary salt production ponds. The seawater used in the aquaculture process is taken from natural seawater, primarily through mechanical water extraction during high tide. The salt pond area is over 500 mu (approximately 33 hectares), with an east-west width of 400m-450m, a north-south length of 850m-950m, and a depth of 3.0m-3.2m. A ring ditch is dug around the salt pond, 1.5m-2m away from the pond's dam, 10m-12m wide, and 40cm-50cm deep. A central ditch is dug in the center of the salt pond, aligning with the inlet and outlet directions, with a slope ratio of 1.8:1.0. Shell beds are set between the ring ditch and the central ditch. The central ditch is 20m-22m wide and 70cm-80cm lower than the pond bottom. Shell beds are set up between the ring ditch and the central ditch. One side of the shell bed is planted with four-cornered clams, and the other side with Manila clams. Each side of the shell bed can be divided into 6 to 8 sections, each section being 100 to 110 meters wide and 180 to 200 meters long, and 25 to 35 centimeters above the bottom of the pond. The shell bed area accounts for 70% to 72% of the total area of ​​the salt flat.

[0020] Disinfection and water intake for salt-bearing ponds: After harvesting the farmed animals in early December, drain the ponds. Before March of the following year, expose the salt-bearing ponds to the sun and remove silt from the ring and central ditches. Afterward, clean the ponds, repair the dikes and sluice gates, and construct shellfish beds. Fifteen days before water intake, disinfect the ring and central ditches with bleaching powder in water, at a depth of 15-25 cm and a bleaching powder concentration of 35 g / m³. 3 Meanwhile, the shellfish beds were covered with polyethylene netting. The salt flats had separate inlet and outlet systems, with double-layered 60-mesh polyethylene netting installed at both inlet and outlet to prevent harmful organisms from entering. Water was introduced in early March, filling the beds to 30cm above the surface.

[0021] Seedling release: Shellfish seedlings are released in late March. The average size of Manila clams is 1300 clams / kg. The Manila clam seedlings are evenly scattered on the shellfish beds at a density of 190 kg / mu to 210 kg / mu. The average size of tetrapod clams is 510 clams / kg. The tetrapod clam seedlings are evenly scattered on the shellfish beds at a density of 130 kg / mu to 150 kg / mu. In mid-April, when the water temperature rises above 15℃, stock Chinese shrimp seedlings with a total length of 0.9cm to 1.1cm. The seedlings should be uniform, clean, vigorous, and free from specific pathogens, with a stocking density of 4,000 to 6,000 shrimp per mu. In early May, when the water temperature rises above 18℃, stock swimming crab seedlings in their second stage. The swimming crab seedlings should be uniform in metamorphosis, vigorous, healthy, and undamaged, with a stocking density of 4,000 to 6,000 crabs per mu.

[0022] In late June, naturally bred gudgeon seedlings with a total length of 3cm to 4cm were captured and the density was 400 to 600 gudgeons per mu.

[0023] Water quality management: After stocking the shellfish larvae, gradually increase the water level to 50-60cm above the shellfish beds. Then, use products such as "fertilizer paste" to cultivate basic food organisms. The water color should ideally be a light green rich in green algae and diatoms, and the water transparency should be maintained at 40-50cm. In July, as the temperature rises, raise the water level to 2.0m above the shellfish beds, and then maintain a relatively stable water level.

[0024] During the aquaculture period, microecological agents are used to regulate water quality: Bacillus and EM bacteria are applied in June and July, and lactic acid bacteria and photosynthetic bacteria are applied in August and September. Bacillus is an aerobic bacterium; to prevent oxygen deficiency in the water, the aerator should be turned on two hours before and after applying Bacillus. In mid-July, due to the increase in temperature and the large load of saltwort, the oxygen consumption of the water increases. At this time, oxygenation should be carried out using mechanical aerators or microporous nanotubes for micro-aeration. Two circular nano-aeration discs with a diameter of 60cm to 80cm are placed per acre.

[0025] Feeding Management: After stocking, the shellfish larvae feed on planktonic food. During the Chinese shrimp farming period, artificial compound feed for Chinese shrimp is given every 5-7 days at a rate of 1-1.5 kg / mu. Feeding begins after stocking stage II larvae of the swimming crab, mainly with live, smooth blue clams, supplemented with frozen small shrimp, at a rate of 80%-50% of the total weight of the swimming crabs. Once the swimming crabs reach stage V, frozen sandworms can be added to the feed.

[0026] Depending on the water temperature and the growth of the swimming crabs, feed them once a day from May to June. From July onwards, feed them twice a day, once in the morning and once in the evening, with the amount of feed being 8% to 10% of the total weight of the swimming crabs. From August to October, feed them 10% to 12% of the total weight of the swimming crabs each day. From November onwards, feed them 3% to 5% of the total weight of the swimming crabs each day until the water temperature drops below 8℃ and then stop feeding.

[0027] During the middle and later stages of aquaculture, the inlet and outlet screens were replaced with double-layered 40-mesh and 20-mesh polyethylene screens to increase water permeability.

[0028] Before the Mid-Autumn Festival, some Chinese shrimp are harvested using traps or seine nets, at which time the shrimp weigh 26g-36g / tail. Depending on the stock of swimming crabs, male swimming crabs are harvested using crab traps or gillnets, at which time the male crabs weigh 128g-224g / each. In late October, the remaining Chinese shrimp and gudgeon are harvested, at which time the gudgeon weigh 145g-200g / tail. In early to mid-November, female swimming crabs are harvested using gillnets, at which time the female crabs weigh 200g-300g / each. In mid to late November, clams and Manila clams are harvested based on market prices. At this time, the average size of clams harvested is 3.08cm, the average weight is 11.1g / clam, and the average yield is 710kg / mu; the average size of Manila clams is 3.2cm, the average weight is 7.2g / clam, and the average yield is 1620kg / mu.

[0029] Example 1: The ecological integrated farming method for Chinese shrimp, swimming crab "Huangxuan No. 2", four-cornered clams, Manila clams, and spotted gudgeon in this example includes the following steps: Construction of the salt flats for aquaculture: The salt flats are located near the intertidal zone, and the seawater used in the aquaculture process is taken from natural seawater, mainly through tidal mechanical pumping. The salt flat area used for aquaculture is 510 mu (approximately 34 hectares), with an east-west width of 400m, a north-south length of 850m, and a depth of 3.0m. A ring ditch is dug around the salt flat, 1.5m away from the salt flat dike, and 10m wide, 60cm-70cm below the bottom of the pond. A central ditch is dug in the center of the salt flat, running in the same direction as the inlet and outlet. The central ditch is 20m wide and 60cm-70cm below the bottom of the pond. Shell beds are set between the ring ditch and the central ditch. Each shell bed is 188m wide and 100m long, 20cm-25cm above the bottom of the pond. The shell bed area accounts for 71.92% of the salt flat area.

[0030] Disinfection and water intake for salt-bearing ponds: After harvesting the farmed animals in early December, drain the ponds. Before March of the following year, expose the salt-bearing ponds to the sun and remove silt from the ring and central ditches. Afterward, clean the ponds, repair the dikes and sluice gates, and construct shellfish beds. Fifteen days before water intake, disinfect the ring and central ditches and shellfish beds with bleaching powder in water at a depth of 15-20 cm and a bleaching powder concentration of 35 g / m³. 3 At the same time, the shell beds are covered with polyethylene netting.

[0031] The salt flats have separate inlet and outlet systems, with double-layered 60-mesh polyethylene netting installed at both inlet and outlet to prevent harmful organisms from entering. Water is introduced in early March, filling the area to 30cm above the surface of the shell beds. After July, the inlet and outlet are replaced with double-layered 40-mesh polyethylene netting, and after early August, they are replaced with double-layered 20-mesh polyethylene netting.

[0032] Seedling stocking: In late March, stock juvenile four-cornered clams and Manila clams. Four-cornered clams have an average size of 510 clams / kg, and are evenly scattered on the shellfish beds at a stocking density of 130 kg / mu. Manila clams have a size of 1300 clams / kg, and are evenly scattered on the shellfish beds at a stocking density of 190 kg / mu. In late April, when the water temperature rises above 15℃, stock juvenile Chinese shrimp (0.8cm-1.1cm in total length). The shrimp should be uniform, clean, vigorous, and free of specific pathogens, at a stocking density of 4000 shrimp / mu. In early May, when the water temperature rises above 18℃, stock stage II swimming crabs (14,000 crabs / kg). The swimming crabs should have uniform metamorphosis, be vigorous, healthy, and undamaged. The stocking density for stage II swimming crabs is 4000 crabs / mu.

[0033] In late June, 3-4 cm long sea gudgeon were released at a density of 400 fish per acre.

[0034] Water Quality Management: After stocking the shellfish larvae, gradually increase the water level to 50cm above the shellfish beds. Then, use products such as "fertilizer paste" to cultivate basic food organisms. The water color should ideally be a light green rich in algae. Maintain water transparency at 40cm-50cm. In July, as the temperature rises, raise the water level to 1.7m above the shellfish beds, and then maintain a relatively stable water level. Use microecological agents to regulate water quality during the aquaculture period. Apply Bacillus and EM bacteria in June and July, and apply lactic acid bacteria and photosynthetic bacteria in August and September to regulate water quality. Bacillus is an aerobic bacterium; to prevent oxygen deficiency, turn on the aerator 2 hours before and after applying Bacillus. In mid-July, due to rising temperatures and high salinity, oxygen consumption increases. At this time, use mechanical aerators or microporous nanotubes for micro-aeration. Place one 3kW aerator per 40 acres, or two 60cm diameter circular nano-aeration discs per acre.

[0035] Feeding Management: After stocking, the shellfish larvae feed on planktonic food. During the Chinese shrimp farming period, artificial feed for Chinese shrimp is added to the pond every 5 days at a rate of 1 kg / mu. Feeding begins after stocking stage II juvenile swimming crabs, primarily with live, smooth blue clams, supplemented with frozen small shrimp. Once the swimming crabs reach stage V, frozen sandworms can be added. Depending on water temperature and crab growth, feed once daily from May to June, at a rate of 80%–50% of the total weight of the swimming crabs; from July onwards, feed twice daily, once in the morning and once in the evening, at a rate of 8% of the total weight of the swimming crabs; from August to October, feed 10% of the total weight of the swimming crabs daily; from November onwards, feed 3% of the total weight of the swimming crabs daily until the water temperature drops below 6℃, at which point feeding is discontinued.

[0036] During the aquaculture period, if the average daily water temperature is ≥28℃, change the water once a day, draining a 35-40cm layer of water from the bottom each time. If the average daily water temperature is <28℃, change the water every 2-3 days, using a bottom water change method, draining a 25-30cm layer of water from the bottom each time. After heavy rain, replenish with fresh water promptly to prevent excessive salinity changes. Inspect the water twice a day, in the early morning and evening, and measure the water temperature, dissolved oxygen, transparency, and salinity daily. Examine the plankton in the water every two days under a microscope to observe changes in the quantity and characteristics of the plankton population.

[0037] Before the Mid-Autumn Festival, some Chinese shrimp are harvested using traps or seine nets, at which time the shrimp weigh 23-32g / shrimp. Depending on the stock of swimming crabs, male swimming crabs are harvested using crab traps or gillnets, at which time the male crabs weigh 120g-190g / crab. In mid-to-late October, the remaining Chinese shrimp and gudgeon are harvested, at which time the gudgeon weigh 135g-160g / crab. In early to mid-November, female swimming crabs are harvested using crab traps or gillnets, at which time the female crabs weigh 200g-286g / crab. From late November to early December, shellfish are harvested according to market prices. The average size of four-cornered clams is 3.07cm, the average weight is 10.8g / clam, and the average yield is 630kg / mu. The average size of Manila clams is 3.12cm, the average weight is 7.4g / clam, and the average yield is 1580kg / mu.

[0038] Example 2: The ecological integrated farming method for Chinese shrimp, swimming crab "Huangxuan No. 2", four-cornered clams, Manila clams, and spotted gudgeon in this example includes the following steps: Construction of the salt flats for aquaculture: The salt flats are located near the intertidal zone, and the seawater used in the aquaculture process is taken from natural seawater, mainly through tidal mechanical pumping. The salt flat area used for aquaculture is 600 mu (approximately 40 hectares), with an east-west width of 430m, a north-south length of 930m, and a depth of 3.2m. A ring ditch is dug around the salt flat, 2.0m away from the salt flat dike. A central ditch is dug in the center of the salt flat, oriented in the same direction as the water inflow. The ring ditch is 11m wide and 50cm below the bottom of the pond; the central ditch is 21m wide and 80cm below the bottom of the pond. Shell beds are set up on the side closest to the dike and on both sides of the central ditch. Each shell bed is 190m long and 100m wide, with 7 shell beds on each side, and is 35cm above the bottom of the pond. The shell bed area accounts for 72.53% of the salt flat area.

[0039] Disinfection and water intake for salt-bearing ponds: After harvesting the farmed animals in early December, drain the ponds. Before March of the following year, expose the salt-bearing ponds to the sun and remove silt from the ring and central ditches. Afterward, clean the ponds, repair the dikes and sluice gates, and construct shellfish beds. Fifteen days before water intake, disinfect the ring and central ditches with bleaching powder in water at a depth of 20-25 cm and a bleaching powder concentration of 35 g / m³. 3 At the same time, the shell beds are covered with polyethylene netting.

[0040] The salt flats have separate inlet and outlet systems, with double-layered 60-mesh polyethylene netting installed at both inlet and outlet to prevent harmful organisms from entering. Water is introduced in early March, filling the flats to 30cm above the surface.

[0041] Seedling stocking: In late March, stock juvenile four-cornered clams and Manila clams. Four-cornered clams have an average size of 510 clams / kg, and are evenly scattered on the shellfish beds at a stocking density of 140 kg / mu. Manila clams have a size of 1300 clams / kg, and are evenly scattered on the shellfish beds at a stocking density of 200 kg / mu. In late April, when the water temperature rises above 15℃, stock juvenile Chinese shrimp (0.9cm-1.1cm in total length). The juveniles must be uniform, clean, vigorous, and free of specific pathogens, with a stocking density of 5000 shrimp / mu. In early May, when the water temperature rises above 18℃, stock stage II swimming crab (14,000 crabs / kg) at a stocking density of 5000 crabs / mu. The swimming crabs must have uniform metamorphosis, be vigorous, healthy, and undamaged.

[0042] In late June, 3-4 cm long sea gudgeon were released at a density of 500 gudgeons per acre.

[0043] Water Quality Management: After stocking the shellfish larvae, gradually increase the water level to 60cm above the shellfish beds. Then, use products such as "fertilizer paste" to cultivate basic food organisms. The water color should ideally be a light green rich in green algae and diatoms. Maintain water transparency at 40cm-50cm. In July, as the temperature rises, raise the water level to 1.8m above the shellfish beds, and then maintain a relatively stable water level. Use microecological agents to regulate water quality during the aquaculture period. Apply Bacillus and EM bacteria in June and July, and apply lactic acid bacteria and photosynthetic bacteria in August and September to regulate water quality. Bacillus is an aerobic bacterium; to prevent oxygen deficiency, turn on the aerator 2 hours before and after applying Bacillus. In mid-July, due to rising temperatures and a large saltwort load, the oxygen consumption of the water increases. At this time, use aerators or microporous nanotubes for micro-aeration. Install one 3kW aerator per 50 acres or two 70cm diameter circular nano-aeration discs per acre.

[0044] Feeding Management: After stocking, shellfish feed on planktonic food. During the Chinese shrimp farming period, artificial compound feed for Chinese shrimp is added to the pond every 4 days at a rate of 1.3 kg / mu. Feeding begins after stocking stage II juvenile swimming crabs, primarily with live, smooth blue clams, supplemented with frozen small shrimp. Once the swimming crabs reach stage V, frozen sandworms and frozen goby can be added. Depending on water temperature and crab growth, feed once daily from May to June, at a rate of 70%–50% of the total weight of the swimming crabs; from July onwards, feed twice daily, once in the morning and once in the evening, at a rate of 9% of the total weight of the swimming crabs; from August to October, feed 11% of the total weight of the swimming crabs daily; from November onwards, feed 5% of the total weight of the swimming crabs daily until the water temperature drops below 8℃, at which point feeding is discontinued.

[0045] During the aquaculture period, if the average daily water temperature is ≥28℃, change the water once a day, draining a 40cm-45cm layer of water from the bottom each time. If the average daily water temperature is <28℃, change the water every 2-3 days, using a bottom water change method, draining a 25cm-30cm layer of water from the bottom each time. After heavy rain, replenish the water promptly to prevent excessive salinity changes. Inspect the water twice a day, morning and evening, and measure water temperature, dissolved oxygen, transparency, salinity, and other water quality indicators daily. Examine plankton microscopically every two days to observe changes in the quantity and characteristics of the plankton community.

[0046] Before the Mid-Autumn Festival, some Chinese shrimp are harvested using traps or seine nets, at which time the shrimp weigh 26g-35g / shrimp. Depending on the stock, male swimming crabs are harvested using crab traps or gillnets, at which time the males weigh 128g-205g / crab. In early to mid-November, the remaining Chinese shrimp and gudgeon are harvested, at which time the gudgeon weigh 135g-154g / shrimp. In mid-to-late November, female swimming crabs are harvested using gillnets, at which time the females weigh 210g-280g / crab. From late November to early December, clams and Manila clams are harvested based on market prices. At this time, the average size of clams harvested is 3.11cm, the average weight is 10.9g / clam, and the average yield is 650kg / mu; the average size of Manila clams is 3.16cm, the average weight is 7.7g / clam, and the average yield is 1680kg / mu.

[0047] Example 3: The ecological integrated farming method for Chinese shrimp, swimming crab "Huangxuan No. 2", four-cornered clams, Manila clams, and spotted gudgeon in this example includes the following steps: Construction of the salt flats for aquaculture: The salt flats are located near the intertidal zone, and the seawater used in the aquaculture process is taken from natural seawater, mainly through tidal mechanical pumping. The salt flat area used for aquaculture is 728 mu (approximately 41.5 hectares), with an east-west width of 450m, a north-south length of 1080m, and a depth of 3.2m. A ring ditch is dug around the salt flat, 2m away from the salt flat dam. A central ditch is dug in the center of the salt flat, running in the same direction as the water inflow. The ring ditch is 12m wide and 50cm below the bottom of the pond; the central ditch is 22m wide and 80cm below the bottom of the pond. Between the ring ditch and the central ditch are shell beds, each 200m wide and 100m long, 30cm above the bottom of the pond. The shell bed area accounts for 72.3% of the salt flat area.

[0048] Disinfection and water intake for salt-bearing ponds: After harvesting the farmed animals in early December, drain the ponds. Before March of the following year, expose the salt-bearing ponds to the sun and remove silt from the ring and central ditches. Afterward, clean the ponds, repair the dikes and sluice gates, and construct shellfish beds. Fifteen days before water intake, disinfect the ring and central ditches and shellfish beds with bleaching powder in water at a depth of 25-30 cm and a bleaching powder concentration of 35 g / m³. 3 At the same time, the shell beds are covered with polyethylene netting.

[0049] The salt ponds have separate inlet and outlet systems, with double-layered 60-mesh polyethylene netting installed at both inlet and outlet to prevent harmful organisms from entering. Water is introduced in early March, filling the ponds to 35cm above the surface.

[0050] Seedling stocking: In late March, stock juvenile four-cornered clams and Manila clams. Four-cornered clams have an average size of 500 clams / kg, and are evenly scattered on the shellfish beds at a stocking density of 150 kg / mu. Manila clams have a size of 1280 clams / kg, and are evenly scattered on the shellfish beds at a stocking density of 220 kg / mu. In late April, when the water temperature rises above 15℃, stock juvenile Chinese shrimp (0.9cm-1.1cm in total length). The juveniles must be uniform, clean, vigorous, and free of specific pathogens, with a stocking density of 6000 shrimp / mu. In early May, when the water temperature rises above 18℃, stock stage II swimming crab (12,000 crabs / kg) at a stocking density of 6000 crabs / mu. The swimming crabs must have uniform metamorphosis, be vigorous, healthy, and undamaged.

[0051] In late June, 3-4 cm long sea gudgeon were released at a density of 600 fish per acre.

[0052] Water Quality Management: After stocking the shellfish larvae, gradually increase the water level to 60cm above the shellfish beds. Then, use products such as "fertilizer paste" to cultivate basic food organisms. The water color should ideally be a light green rich in green algae and diatoms. Maintain water transparency at 40cm-50cm. In July, as the temperature rises, raise the water level to 2.1m above the shellfish beds, and then maintain a relatively stable water level. Use microecological agents to regulate water quality during the aquaculture period. Apply Bacillus and EM bacteria in June and July, and apply lactic acid bacteria and photosynthetic bacteria in August and September to regulate water quality. Bacillus is an aerobic bacterium; to prevent oxygen deficiency, turn on the aerator 2 hours before and after applying Bacillus. In mid-July, due to rising temperatures and high salinity, oxygen consumption increases. At this time, use mechanical aerators or microporous nanotubes for micro-aeration. Place one 3kW aerator or two 80cm diameter circular nano-aeration discs per 45 acres.

[0053] Feeding Management: After stocking, the shellfish larvae feed on planktonic food. During the Chinese shrimp farming period, artificial feed for Chinese shrimp is introduced into the pond every 4 days at a rate of 1.5 kg / mu. Feeding begins after stocking stage II juvenile swimming crabs, primarily with live, smooth blue clams, supplemented with frozen small shrimp. Once the swimming crabs reach stage V, frozen small miscellaneous fish can be added. Depending on the water temperature and the growth of the swimming crabs, feed once daily from May to June, at a rate of 85%–50% of the total weight of the swimming crabs; from July onwards, feed twice daily, once in the morning and once in the evening, at a rate of 10% of the total weight of the swimming crabs; from August to October, feed 12% of the total weight of the swimming crabs daily; from November onwards, feed 4% of the total weight of the swimming crabs daily until the water temperature drops below 8℃, at which point feeding is discontinued.

[0054] During the aquaculture period, if the average daily water temperature is ≥28℃, change the water once a day, draining a 40cm-50cm layer of water from the bottom each time. If the average daily water temperature is <28℃, change the water every 2-3 days, using a bottom water change method, draining a 25cm-35cm layer of water from the bottom each time. After heavy rain, replenish the water promptly to prevent excessive salinity changes. Inspect the water twice a day, once in the early morning and once in the late afternoon, and measure physicochemical factors such as water temperature, dissolved oxygen, silica, and transparency daily. Examine the plankton in the water every two days, paying close attention to changes in the quantity and characteristics of the plankton population.

[0055] Before the Mid-Autumn Festival, some Chinese shrimp are harvested using traps or seine nets, at which time the shrimp weigh 26g-37g / shrimp. Male swimming crabs are harvested using crab traps or gillnets, at which time the males weigh 128g-210g / crab. In early to mid-November, the remaining Chinese shrimp and gudgeon are harvested, at which time the gudgeon weigh 138g-154g / crab. In mid-to-late November, female swimming crabs are harvested using crab traps or gillnets, at which time the females weigh 220g-315g / crab. From late November to early December, clams and Manila clams are harvested according to market prices. The average size of the harvested clams is 3.10cm, the average weight is 10.8g / clam, and the average yield is 670kg / mu. The average size of the Manila clams is 3.18cm, the average weight is 7.8g / clam, and the average yield is 1720kg / mu.

[0056] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A method for large-scale, three-dimensional ecological aquaculture of shrimp, crabs, shellfish, and fish utilizing complementary ecological niches, characterized by: Includes the following steps: Select salt-producing ponds in the intertidal zone and construct aquaculture salt ponds with an area of ​​more than 500 mu. The aquaculture salt ponds are 400m to 450m wide from east to west, 850m to 950m long from north to south, and 3.0m to 3.2m deep. Dig a ring ditch around the aquaculture salt ponds and dig a central ditch in the same direction as the water inlet and outlet. Set up shell beds between the ring ditch and the central ditch. The slope ratio of the water inlet and outlet directions is 1.8:1.

0. After the harvest was completed in early December of that year, the pond water was drained. Before March of the following year, the salt pond was exposed to the sun, dredged, and cleaned and repaired. Fifteen days before water was introduced, the ring ditch, central ditch, and shell beds were disinfected with bleaching powder. At the same time, the shell beds were covered with polyethylene netting. The salt pond was separated for water inlet and outlet, and double-layered 60-mesh polyethylene netting was installed at the inlet and outlet. In early March, the water was introduced to a depth of 30cm above the surface of the shell beds. In late March, four-cornered clam and Manila clam seedlings are stocked into the shellfish beds. The four-cornered clam seedlings have an average shell length of 2cm and a stocking density of 130kg / mu to 150kg / mu. The Manila clam seedlings have an average shell length of 1.1cm and a stocking density of 190kg / mu to 210kg / mu. In mid-April, when the water temperature is ≥15℃, Chinese shrimp seedlings with a total length of 0.9cm to 1.1cm are stocked at a density of 4000 to 6000 shrimp / mu. In early May, when the water temperature is ≥18℃, swimming crab (Portunus trituberculatus) seedlings (stage II) are stocked at a density of 4000 to 6000 crabs / mu. In late June, spotted gudgeon seedlings with a length of 3cm to 4cm are stocked at a density of 400 to 600 gudgeons / mu. After releasing the shellfish larvae, gradually increase the water level to 50-60cm above the shellfish beds. Use water quality nutrients to cultivate basic food organisms, controlling the water color to a light green rich in green algae and diatoms, and the water transparency to 40-50cm. In July, raise the water level to 1.7m-2.0m above the shellfish beds and maintain it stable. Apply Bacillus and EM bacteria in June and July, and apply lactic acid bacteria and photosynthetic bacteria in August and September to regulate water quality. Start aeration in mid-July. Adjust water quality by bottom water exchange according to water temperature, and replenish fresh water promptly after heavy rain. Measure water temperature, dissolved oxygen, salinity, and transparency daily, and examine plankton microscopically every two days. Four-cornered clams and Manila clams feed on planktonic food. During the Chinese shrimp farming period, artificial compound feed is given every 5 to 7 days at a rate of 1 kg / mu to 1.5 kg / mu. Feeding begins after the release of the second-stage seedlings of swimming crabs, with fresh, smooth blue clams as the main feed and frozen small shrimp as a supplement. After the fifth stage, frozen sandworms are added. The feeding frequency and amount are adjusted according to the water temperature and growth conditions. Some Chinese shrimp are harvested before the Mid-Autumn Festival, the remaining Chinese shrimp and gudgeon are harvested in late October, and swimming crabs are harvested from late October to mid-November; clams and Manila clams are harvested from late November to early December.

2. The method for large-scale three-dimensional ecological aquaculture of shrimp, crab, shellfish and fish utilizing complementary ecological niches as described in claim 1, characterized in that: The ring ditch mentioned in step one is 10m to 12m wide, 1.5m to 2m away from the salt pond embankment, and 40cm to 50cm below the bottom of the pond; the central ditch is 20m to 22m wide and 50cm to 70cm below the bottom of the pond. The shell beds are divided into 6 to 8 sections, each section being 100m to 110m wide, 180m to 200m long, and 25cm to 35cm higher than the bottom of the pond. The area of ​​the shell beds accounts for 70% to 72% of the total area of ​​the salt pond. Four-cornered clams were planted on one side of the shellfish bed, while Manila clams were planted on the other side.

3. The method for large-scale three-dimensional ecological aquaculture of shrimp, crab, shellfish and fish utilizing complementary ecological niches as described in claim 2, characterized in that: In step two, when disinfecting with bleach, control the water depth to 15cm-25cm and the bleach concentration to 35g / m³, and rinse twice after disinfection; During the middle and later stages of aquaculture, the netting at the inlet and outlet was replaced with double-layered 40-mesh and 20-mesh polyethylene netting, respectively.

4. The method for large-scale three-dimensional ecological aquaculture of shrimp, crab, shellfish and fish utilizing complementary ecological niches as described in claim 1, characterized in that: In step one, the seedlings of four-cornered clams and Manila clams are evenly sown in the shellfish beds; Chinese shrimp larvae must be uniform, clean, vigorous, and free from specific pathogens; The seedlings of the three-spotted swimming crab (Portunus trituberculatus) in the second stage require uniform metamorphosis, vigorous activity, and good health without damage, with a size of 12,000 to 14,000 crabs / kg; The gudgeon seedlings are naturally bred and caught at sea.

5. A method for large-scale three-dimensional ecological aquaculture of shrimp, crabs, shellfish, and fish utilizing complementary ecological niches, as described in claim 1, is characterized in that: The water nutrient agent mentioned in step four is a fertilizer paste; Turn on the oxygenation equipment 2 hours before and after applying Bacillus subtilis; the oxygenation method is mechanical oxygenation by an aerator or microporous nanotube micro-aeration oxygenation, and place 2 circular nano oxygenation discs with a diameter of 60cm to 80cm per acre. The water change rule is as follows: when the average daily water temperature is ≥28℃, change the water once a day, drain the water first and then add water, draining 40cm to 50cm from the bottom each time; When the average daily water temperature is less than 28℃, change the water every 2 to 3 days, draining 20cm to 30cm from the bottom each time.

6. A method for large-scale three-dimensional ecological aquaculture of shrimp, crab, shellfish and fish utilizing complementary ecological niches, as described in claim 5, is characterized in that: Aerators were installed every 125 meters along the north-south direction of Yanwangzi, 40 meters away from the Yanwangzi dike. Do not bottom-seed shellfish within a 25m radius of the aerator or nano-aeration disc.

7. A method for large-scale three-dimensional ecological aquaculture of shrimp, crab, shellfish and fish utilizing complementary ecological niches, as described in claim 1, is characterized in that: In step five, the artificial compound feed for Chinese shrimp is a special compound feed for shrimp, which is evenly spread in the area between the ring ditch and the central ditch of the salt pond when it is put in.

8. A method for large-scale three-dimensional ecological aquaculture of shrimp, crabs, shellfish, and fish utilizing complementary ecological niches, as described in claim 1, is characterized in that: The feeding parameters for the three-spined swimming crabs in step five are as follows: feed once a day from May to June, with the feeding amount being 50% to 80% of the total weight of the three-spined swimming crabs; In July, feed twice a day, once in the morning and once in the evening, with the amount of feed being 8% to 10% of the total weight; From August to October, feed twice a day, once in the morning and once in the evening, with the amount of feed being 10% to 12% of the total weight; Feed once a day starting in November, with the amount of feed being 3% to 5% of the total weight. Stop feeding when the water temperature is below 8℃.

9. A method for large-scale three-dimensional ecological aquaculture of shrimp, crabs, shellfish, and fish utilizing complementary ecological niches, as described in claim 1, is characterized in that: It also includes daily pond patrol procedures: patrol the pond once each in the early morning and evening to check the feeding, growth and activity of the farmed organisms, and promptly clean up any uneaten feed and dead bodies in the aquaculture water.

10. A method for large-scale three-dimensional ecological aquaculture of shrimp, crab, shellfish and fish utilizing complementary ecological niches, as described in claim 1, is characterized in that: In step six, Chinese prawns and gudgeon are harvested using traps or seine nets, swimming crabs are harvested using crab traps or gillnets, and four-cornered clams and Manila clams are harvested using harvesting tools. At harvest time, Chinese prawns weigh 23g-37g / tail, male swimming crabs weigh 120g-224g / each, female swimming crabs weigh 200g-315g / each, spotted gudgeon weigh 135g-200g / tail, four-cornered clams have an average shell length of ≥3.0cm, and Manila clams have an average shell length of ≥3.1cm.

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