Clam land-based breed conservation system and breed conservation management method

Abstract

The invention belongs to the technical field of aquaculture, and provides a land-based breed conservation system and a breed conservation management method.The land-based breed conservation system comprises a breed conservation unit, a fertilizer and water unit and a breeding tail water collection unit, the breed conservation unit is formed by arranging a plurality of breed conservation pools side by side, yellow sand is laid at the bottoms of the pools, and the breed conservation pools are arranged in the breeding tail water collection unit; a first water outlet is formed in the position, close to a sewer, of the bottom of the breed conservation pool, the yellow sand is obliquely laid to the first water outlet from top to bottom, and a first water drainage insertion pipe connected in a separated mode is arranged on the first water outlet; the water fertilizing unit comprises two water fertilizing pools, the water fertilizing pools are bowl-shaped, and fishes, shrimps and crabs are bred in the water fertilizing pools in a mixed mode; the breeding tail water unit comprises a sewer, the sewer is communicated with the first water outlet of each breed conservation pond, and the sewer is communicated with the fertile water pond. The method solves the key technical problems of low efficiency, high death rate, difficulty in breeding management and the like in the process of collecting, transporting and storing the meretrix meretrix germplasm resources.

Description

Technical Field

[0001] This invention relates to the field of aquaculture technology, specifically to a method for the land-based preservation, transportation, and cultivation of clams. Background Technology

[0002] Clams ( Meretrix meretrix The hard clam is one of the most important bivalve economic shellfish species in my country, widely distributed in various sea areas of my country. The coastal areas of the Liaohe River Estuary in Liaoning, the coastal areas of Laizhou Bay in Shandong, the coastal areas of Nantong in Jiangsu, and the coastal areas of Hepu in Guangxi are the four major production areas of hard clam in my country. In addition, there are different geographical groups of hard clams in southern Zhejiang, the west coast of Taiwan, the coastal areas of Fujian, the Pearl River Estuary in Guangdong, and the coast of Hainan. The germplasm resources of hard clams are very rich. The color, pattern and shell shape of hard clam shells also vary in different groups, and there are some mutants in shell color, shell shape and traits, which can serve as the material basis for the development of new varieties. However, since the end of the last century, disorderly north-south transplantation has become increasingly frequent, and the phenomenon of germplasm mixing has become increasingly serious, showing different degrees of degradation and gradually deteriorating. The main problems faced by the existing technology are: (1) lack of a complete land-based conservation system, making it difficult to systematically manage different hard clam germplasm resources on the basis of long-term cultivation; (2) frequent algae blooms in the conservation ponds leading to a large number of deaths of hard clam individuals; (3) low survival rate of different germplasm collected through off-site hard clam transplantation in land-based conservation facilities.

[0003] Addressing the current state of clam germplasm resources and industry demands requires long-term planning and strategy. Therefore, establishing a "Noah's Ark"-like protection system to prevent the large-scale destruction of superior clam germplasm through ex-situ relocation is of paramount importance. Currently, there are no reports in China of preserving different clam species using land-based conservation methods. Jiangsu Province, as the leading clam-producing region among the four major producing areas and located in the middle of my country's coastal areas, is well-suited for collecting and preserving clam germplasm resources. Therefore, this invention establishes a method for land-based conservation, transportation, and cultivation of clam, which is crucial and provides strong support for the in-depth development of the clam breeding industry. Summary of the Invention

[0004] The technical problem this invention aims to solve is to provide a land-based conservation system and management method for hard clam, addressing key technical issues such as high mortality rate, low survival rate, and difficult aquaculture management caused by the lack of a robust land-based conservation system. By establishing a land-based hard clam germplasm conservation system, original species and high-quality germplasm resources (potential breeding materials, new varieties, and new strains) from different geographical populations of hard clams are concentrated in one location for off-site re-cultivation, improving the survival rate of the conserved species and forming a living germplasm bank for hard clam. This provides a long-term, stable gene pool and germplasm materials for selecting superior farmed varieties and creating new germplasm.

[0005] To solve the above technical problems, the embodiment of the present application provides a clam land-based seed bank system, which comprises a seed bank unit, a fertilizer water unit and a breeding tail water collecting unit, the seed bank unit is formed by several seed bank pools arranged side by side, the seed bank pool is rectangular, the bottom of the seed bank pool is paved with yellow sand, the bottom of the seed bank pool is provided with a first drainage port near the sewer, the yellow sand is inclined from top to bottom to the drainage port, and the drainage port is provided with a first drainage insertion pipe connected in a detachable manner; The fertilizer water unit comprises two fertilizer water pools, the fertilizer water pool is bowl-shaped, the area of each fertilizer water pool is 3-4 mu, one side of the fertilizer water pool is provided with a second drainage port, the second drainage port is communicated with an external drainage main channel, the fertilizer water pool is communicated with the water inlet pipe of the seed bank unit through a floating pump pipeline, and fish, shrimp and crab are mixedly bred in the fertilizer water pool; The breeding tail water unit comprises a sewer, one side of the sewer is communicated with the external drainage main channel, a gate is arranged at the connection position of the tail end of the sewer and the external drainage main channel, the sewer is communicated with the first drainage port of each seed bank pool, and the sewer is communicated with the fertilizer water pool.

[0006] The first drainage insertion pipe is provided with three length specifications, i.e., a first drainage insertion pipe with a length of 20-30 cm for cleaning the beach surface and the yellow sand bottom of the seed bank pool, a first drainage insertion pipe with a length of 60-70 cm for use in the rainy season, and a first drainage insertion pipe with a length of 80-90 cm for use in normal breeding.

[0007] The drainage port is further provided with a brick wall fence around the drainage port to prevent the yellow sand from flowing into the drainage port and causing the loss of the bottom.

[0008] The breeding tail water unit further comprises a pvc pipe, one end of the pvc pipe is communicated with the sewer, the other end of the pvc pipe is arranged at the bottom of the fertilizer water pool, and the pvc pipe is provided with a second drainage insertion pipe, when the second drainage port and the gate are closed, the water body in the seed bank unit and the fertilizer water unit forms a self-circulation.

[0009] The embodiment of the present application further provides a clam land-based seed bank management method based on the clam land-based seed bank system, which comprises the following steps: (1) Transplanting: the temperature difference between the original habitat and the seed bank site is less than 5 DEG C, the transplanting is performed in the autumn when the temperature decreases, and the collection of the northern population is completed before the local sea is closed; (2) Transportation: the clams for transplanting from other places are packaged by using a nylon net bag, the bag opening is tightly tied and forms a live buckle, and the clam is packaged by using a foam box and an ice bottle; (3) Adaptive self-breeding: the clams transplanted from other places are adaptively bred in the seed bank pool, the breeding density is distributed according to the shell length specification, after overwintering, in the first breeding season of the seed bank site, a plurality of clam individuals are randomly selected for breeding, and through artificial breeding, seedling cultivation and finished product breeding, 10-20 thousand clams are reserved to construct a seed bank population of the transplanted population from other places. (4) Water exchange management: Observe the water transparency of the seed preservation pond daily, and drain the seed preservation pond twice a day, with each water exchange being 50% of the total volume. Then, transfer the water into the fertilization pond and ensure that the transparency is >50cm for at least 8 hours. (5) Management of moss: Drain the water from the breeding pond, prepare a solution with a concentration of 80 mg / L using 500 g of trichloroisocyanuric acid (containing 30% chlorine), and spray it on the yellow sand beach of the bottom through a sprayer. After spraying, dry the pond for 2-3 hours, then fill it with water and restore it to the normal aquaculture water level. (6) Shading management: A 2m high steel frame is set up along the upper edge of the seed preservation pond. When the temperature is >30℃, a shade net is laid on the steel frame. On windy days, the shade net is pulled back to both sides of the steel frame and then pulled back open afterward. (7) Rainy season management: Use a first drainage pipe with a length of 60-70cm and fill the water level of the seed preservation pond to be level with the upper edge of the first drainage pipe of 60-70cm to ensure that a large amount of fresh water is automatically discharged in time and to keep the water body stable after heavy rain; (8) Overwintering management: When the water temperature is maintained at 10℃~15℃ for 5 consecutive days, choose a sunny day and shovel all the clams and bottom sand in the breeding pond into a plastic basket with a hole diameter of 0.8~1cm. Use a water pump to wash the remaining sand back into the pond. The clams, sandworms, and miscellaneous clams are left in the plastic basket. After removing the sandworms and miscellaneous clams, weigh the clams and collect the basic data of the clams to enter into the breeding file. Then, according to the shell length specifications and breeding density, they are re-sown into the original breeding pond. Before the clams are re-entered into the pond, the bottom sand of the breeding pond is leveled again to meet the overwintering needs, and the thickness is increased by 5~6cm on the basis of the original bottom thickness. After all the work is completed, the water level is filled to the maximum and water is changed every day.

[0010] In step (2), the specific steps of transportation include: packing the clams into bags of 40-50 jin each using nylon mesh bags, rinsing the nylon mesh bags with fresh water from four directions (front, back, left, and right) using a 1-inch water pipe pump, ensuring that the water is clear and there is no sticky residue, and then sealing and transporting them in foam boxes and ice bottles.

[0011] In step (3), the corresponding distribution of culture density based on shell length is as follows: 500-750 shells / m² for shell lengths of 1-2cm. 2 Shell length 2-3cm, 250-500 per m 2 Shell length 3-4cm, 150-300 per m 2 Shell length > 4cm is calculated at 100 shells / m 2 .

[0012] In step (4), the specific steps of water changing include: using clear water and fertilizer water in combination, adopting progressive water changing, when the transparency in the seed preservation pond is less than 30 cm for more than 6 hours after single water changing, changing 50% clear water in the seed preservation pond, and observing the floating sand and death of the clams, if no abnormality is found, keeping the water transparency until more than 50 cm, and then changing water, gradually achieving that the transparency is more than 50 cm for more than 8 hours per day.

[0013] The beneficial effects of the above technical solutions of the present application are as follows: The present application sets a clam land-based seed preservation system and a clam land-based seed preservation management method, first constructs a specific clam land-based seed preservation system to provide necessary conditions for improving seed preservation efficiency, secondly collects, transports and adaptively breeds different clam germplasm resources to be key material conditions for improving seed preservation efficiency, and finally guarantees long-term preservation of different clams under the land-based seed preservation system through a series of daily management such as water changing, moss management, sunshade management, rainy season management and overwintering management, provides protection for the clam living germplasm bank, and can continuously provide seed sources for new variety creation. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 Fig. 1 is a structural schematic diagram of the clam land-based seed preservation system of the present application.

[0015] MARKS OF THE DRAWINGS 1, seed preservation pond; 2, first drainage port; 3, first drainage insertion pipe; 4, yellow sand; 5, brick wall; 6, water inlet pipe; 7, fertilizer pond; 8, second drainage port; 9, sewer; 10, second drainage insertion pipe; 11, passageway; 12, PVC pipe. DETAILED DESCRIPTION

[0016] In order to make the technical problems, technical solutions and advantages of the present application clearer, specific embodiments will be described in detail below with reference to the drawings.

[0017] As Figure 1As shown, the embodiment of the present application provides a clam land-based seed bank system, which comprises a seed bank unit, a fertilizer and water unit and a breeding tail water collection unit, the seed bank unit is formed by several seed bank pools 1 side by side, a passageway 10 is arranged between two seed bank pools 1, the seed bank pool 1 is rectangular, the length, width and height are 7m, 6m and 0.8m respectively, the pool bottom is paved with yellow sand with a particle size of <10mm, a first drainage port 2 is arranged at the bottom of the seed bank pool 1 close to the sewer 9, the yellow sand 4 is inclinedly paved from top to bottom to the first drainage port 2, a first drainage insertion pipe 3 connected in a detachable manner is arranged on the first drainage port 2, and a water inlet pipe 6 is arranged on both sides of the seed bank pool 1. The first drainage insertion pipe 3 with a length of 20cm is mainly used for routine cleaning of the seed bank pool beach surface and the yellow sand bottom. When used, the drainage port is inserted into the first drainage insertion pipe with a length of 20cm, a 1-inch water pump is used to reverse the bottom to make the water flow from top to bottom to the insertion pipe, and then the beach surface is washed from top to bottom after the whole pool is washed. Through the operation, the dirty water and the false feces and other dirt of clams in the whole pool are concentrated to the first drainage port, when the water level of the seed bank pool is higher than 20cm, the dirty water and the like overflow into the first drainage insertion pipe with a length of 20cm and enter the sewer; after the routine cleaning is completed, the first drainage insertion pipe is pulled out, the dirt deposited around the drainage port is removed, and the 1-inch water pump is used for cleaning.

[0018] The first drainage insertion pipe 3 with a length of 60cm is mainly used in the rainy season. When used, it is ensured that the normal water storage in the seed bank pool reaches the upper edge of the first drainage insertion pipe with a length of 60cm; when it rains, a large amount of surface water in the seed bank pool can be discharged in time to prevent the water body from being quickly diluted to cause the death of clams due to their inadaptation.

[0019] The first drainage insertion pipe 3 with a length of 80cm is mainly used in normal breeding. When used, it is helpful to maintain the water level of the seed bank pool, especially in summer, the water level can be maintained at 80cm to the maximum to prevent the water level from being too low to cause the death of clams due to the high water temperature.

[0020] The bottom yellow sand 4 of the seed bank pool 1 is required to be paved as follows: from top to bottom to the first drainage port 2, the thickness of the middle is 15cm, the thickness of the upstream water inlet end is 30cm, and the outer periphery of the drainage port is surrounded by two layers of brick walls 5 connected end to end to block the sand layer. It should be noted that the two layers of brick walls 5 have the following functions: when the seed bank pool 1 is regularly cleaned by a 1-inch water pump to clean the beach surface and excrement, 1-2 bricks on the backwater side are opened to make the water flow quickly take away the excrement and discharge it out of the seed bank pool 1, and the brick wall 5 on the water side can make the water flow quickly deposit the yellow sand 4 to prevent the yellow sand 4 from being discharged out of the seed bank pool 1 to cause the loss of the bottom.

[0021] The fertilizer water unit comprises two fertilizer water pools 7, which are bowl-shaped or pot-shaped, each with an area of 3-4 mu. The bottom of the fertilizer water pool 7 is designed to facilitate the concentration of metabolites and physical residues of the breeding species at the bottom of the soil pool, which is beneficial to the dredging treatment and the trawl-style concentrated harvesting of the breeding species. A second drainage port 8 is arranged on one side of the fertilizer water pool 7, which is in communication with the external drainage main channel. The fertilizer water pool 7 is in communication with the water inlet pipe of the seed preservation unit through the floating pump pipeline. In this embodiment, fish (black seabream, sea bass, and small yellow croaker), shrimps (spiny-tail white shrimp, Japanese prawn, and South American white prawn), and crabs (three-spotted swimming crab and pseudolatent mud crab) are mixedly bred in the fertilizer water pool. In the case that the second drainage port 8 is closed and the sewer 9 gate is closed, the fertilizer water unit and the seed preservation unit can realize a circulating water system.

[0022] The breeding tail water unit comprises a sewer 9, one side of which is in communication with the external drainage main channel. A gate is arranged at the end of the sewer 9 where it is connected to the external drainage main channel. The sewer 9 is in communication with the first drainage port 2 of each seed preservation pool 1. The sewer 9 is in communication with the two fertilizer water pools 7 through pvc pipes 11, and the pvc pipe 12 is arranged at the lowest point of the bottom of the fertilizer water pool 7. A second drainage insertion pipe 10 is arranged on the pvc pipe 12. The gate of the sewer 9 is closed before the seed preservation unit discharges water, and the insertion pipe 10 arranged on the pvc pipe is removed, so that the water in the sewer 9 flows into the fertilizer water pool 7. Due to the water level difference, the higher the water level of the sewer 9, the greater the impact. Therefore, in order to avoid the impact of the water flowing out of the pvc pipe 12 on the dam of the fertilizer water pool 7, the pvc pipe 12 is arranged at the lowest point of the fertilizer water pool 7. At the same time, the water in the sewer 9 forms a water increasing process from bottom to top at the bottom of the fertilizer water pool 7, simulating a tide, and playing a stirring role.

[0023] The embodiment of the present application also provides a clam land-based seed conservation management method based on the clam land-based seed conservation system, which mainly relates to water changing, green algae treatment, sunshade treatment, rainy season management and overwintering treatment. At present, the water changing, sunshade treatment, rainy season management and overwintering treatment in the daily management method of the clam seed conservation have not been reported, the reports related to the green algae control are mainly in the pond culture, and the current control is mainly through the biological method (manual fishing), the physical method (light shielding and transparency reduction), the chemical method (mainly divided into the biological algae inhibition class for killing the green algae by regulating the physiological activity of the green algae, the trifluralin and the triazine class, the triphenylamine herbicide for killing the green algae by blocking the photosynthesis of the green algae, the cationic oxidation class for denaturing the protein of the algae and inactivating the enzyme, and the light shielding and carbon source supplementing class for promoting the growth of the beneficial algae by using humic acid sodium). The biological method and the physical method are time-consuming and labor-consuming, the chemical method can change the pH value and the water quality of the water body, and sometimes the inaccurate dosage can cause the death of the breeding species. Although the literatures report that the quicklime or the bleaching powder is used to kill the green algae, the quicklime or the bleaching powder is used in the case that there is no breeding species in the pond, and the concentration of the chlorine preparation solution for killing the green algae without affecting the clams has not been reported in the articles and the patents.

[0024] The clam land-based seed conservation management method is basically divided into collection, transportation, adaptive breeding and daily management, and specifically includes the following steps: (1) Translocation: the temperature difference between the original habitat and the seed conservation site is less than 5 DEG C, the translocation is performed in the autumn with a temperature drop, and the collection of the northern population is completed before the local sea is closed.

[0025] (2) Transportation: the clams for translocation in different places are packaged with 40-50 kg by using a nylon mesh bag, the bag opening is tightly tied and formed into a live buckle, the foam box is sealed with ice bottles, the individual for transportation is cleaned before being packaged and sealed in the box, so that the survival rate of the transportation is not affected by the high local temperature caused by the impurities such as mud and sand after packaging. In addition, it is worth mentioning that the packaging method is as follows: the nylon mesh bag containing 40 kg of clams is lifted, the bag opening is naturally tightened after rotating several times, the clams are pressed in the nylon mesh bag and cannot open, and then a section of rope is tightly tied as follows.

[0026] (3) Adaptive breeding: the clams translocated in different places are adaptively bred in the seed conservation pond, the breeding density is distributed according to the shell length specifications, after overwintering, more than 100 clam individuals are randomly selected for breeding in the first breeding season of the seed conservation site (the effective parent number is greater than 50 groups to keep the population genetic diversity unchanged), the artificial breeding, seedling cultivation and product breeding are performed, and 10-20 thousand particles are reserved to construct the seed conservation population of the translocated population. The seed conservation population is consistent with the genetic diversity of the original species, the population stability is ensured, and the environmental conditions of the seed conservation site are adapted.

[0027] (4) Water change management: observe the water transparency of the seed bank pool daily, change the water in the seed bank pool at most 2 times a day, each time change 50% of the water, when the transparency is >50 cm, the water can be changed, but the time when the transparency is >50 cm every day should be no less than 8 hours, that is, to ensure that the water in the seed bank pool has a process of fat and thin alternation, to avoid the clam to overfeed for a long time exposed in the fat water. If the transparency in the seed bank pool is <30 cm for more than 6 hours after a single water change, immediately change 50% of the water, and observe the clam floating sand and death on the beach, if no abnormality is found, keep the water transparency until >50 cm before changing the water.

[0028] Among them, the water change rule is as follows: clear water and fat water are used together, progressive water change, gradually reach the time when the transparency is >50 cm every day for no less than 8 hours; if abnormality is found in the clam, drain the pool water, clean the dead clams (use a ball shovel to remove the clam carcasses and the yellow sand with a radius of about 2 cm around the clam habitat, and place them in the collection bin on one side of the tool bucket; the ball shovel is disinfected in the potassium permanganate solution on the other side of the tool bucket before cleaning the next dead clam), rinse the sand surface with a 1-inch water pump after cleaning is completed, dry for 0.5-1 hours after the water is completely drained, then adjust the clear water to half of the pool; the next day, adjust the clear water to half of the pool, then change the water according to the above water change rule until the normal water change.

[0029] (5) Moss management: drain the water in the seed bank pool, use 500g of trichloroisocyanuric acid (containing chlorine 30%) to prepare a solution with a concentration of 80mg / L, spray it on the sand beach of the bottom material through a 20L sprayer, dry for 2-3 hours after spraying, then fill the water in the seed bank pool to the normal breeding water level; (6) Sunshade management: set a 2m high steel frame on the upper edge of the seed bank pool, when the air temperature is >30℃, lay a sunshade net on the steel frame, when typhoon or strong wind, fold the sunshade net to the both sides of the steel frame, then unfold the sunshade net again.

[0030] (7) Rainy season management: use the first drainage pipe with a length of 60cm, and make the water level of the seed bank pool equal to the upper edge of the first drainage pipe with a length of 60cm, to ensure that a large amount of fresh water is automatically drained in time, after heavy rain, keep the water stable; (8) Overwintering management: when the water temperature is continuously 10-15℃ for 5 days, choose a fine day, shovel the clams and the bottom material yellow sand in the seed bank pool into plastic baskets with a hole diameter of 0.8-1cm, and use a water pump to rinse the remaining yellow sand back into the pool, the clams, sandworms and miscellaneous clams are left in the plastic baskets, after removing the sandworms and miscellaneous clams, weigh the clams, collect the basic data and record in the seed bank file, then reseed according to the shell length specifications and breeding density to the original seed bank pool; before the clams are reseeded into the pool, the bottom material yellow sand in the seed bank pool is re-flattened according to the laying principle, and thickened by 5-6cm based on the original thickness to meet the needs of overwintering, after all the work is completed, the water level is filled to the maximum, and daily water change management is maintained.

[0031] The technical solution of the present invention will be further described below with reference to specific embodiments. Example

[0032] I. Clam collection, transportation, and adaptive reproduction within a land-based conservation system A land-based clam conservation system as described in this invention was constructed, and the original clam populations in Rudong, Jiangsu, Qinzhou, Guangxi, and Dandong, Liaoning were preserved. The specific clam collection situation is shown in Table 1.

[0033] Table 1. Collection of original clam populations from Rudong, Jiangsu; Qinzhou, Guangxi; and Dandong, Liaoning.

[0034] (1) Rudong, Jiangsu On October 20, 2021, an asteroid was discovered in the Yaosha-Lengjiasha natural sea area of ​​Rudong County, Jiangsu Province (32.45°130°13'N). (121.671722°E) Collected a population of Rudong clam species. The average shell length of the wild species is 3.60cm, totaling 11,800 specimens. They were divided into four nylon mesh bags. The bags were rinsed with fresh water from all four directions using a 1-inch water pump until clear water and no slime remained. The bag openings were then twisted and tightened, and tied using method A. Two bags were placed in a styrofoam box, with 5-6 ice bottles (550ml) added to each box. The boxes were then sealed and transported back to the land-based conservation facility. For specimens 3-4cm in length, the collection rate was 150-300 specimens / m². 2 The retrieved clams were seeded in the conservation pond (311#) and the survival rate after 2 months of culture was 99.37%.

[0035] On July 3, 2022, 120 mature individuals were randomly selected from #311 for artificial population breeding, yielding 47 million attached seedlings. After juvenile rearing, seedling cultivation, and adult stock farming, 20,000 seedlings were selected when they reached 2.5cm in length, and then cultured at a rate of 250-500 seedlings / m². 2 The individuals were raised in the conservation pond (316#), while the remaining individuals were provided to farmers and were no longer kept in the land-based conservation facility for breeding.

[0036] (2) Qinzhou, Guangxi On November 26, 2021, a population of wild-type hard clam (Clam spp.) was collected from Qinzhou, Guangxi Zhuang Autonomous Region (21.607497°N, 108.531731°E). The average shell length of the wild-type hard clam was 5.31 cm. A total of 4520 hard clam shells were collected and divided into four nylon mesh bags. The mesh bags were rinsed with fresh water from all four directions using a 1-inch water pump until clear water and no mucus were produced. The bag openings were then twisted and tightened, and the bags were sealed using method A. Two bags were placed in a foam box, and 5-6 ice bottles (550 ml) were added to each box. The boxes were then sealed and transported back to the land-based conservation facility. For shells >4 cm, 100 shells / m² were collected.2 The retrieved clams will be seeded in one conservation pond (303#), and the survival rate after 2 months of cultivation is 98.89%.

[0037] On July 10, 2022, 120 mature individuals were randomly selected from the conservation pond (311#) for artificial population breeding, resulting in 47 million attached seedlings. After juvenile cultivation, seedling cultivation, and finished product cultivation, 20,000 were selected at 2.5 cm, and 250-500 / m 2 Cultivation in 316#, the rest of the individuals are provided to the farmers, and no longer remain in the land-based conservation facilities.

[0038] (3) Dandong, Liaoning On October 13, 2021, the Dandong original population was collected from the Dandong sea area (39.960361 °N, 124.282969 °E) in Liaoning Province, with an average shell length of 4.24 cm. A total of 7912 individuals were collected, divided into 4 nylon mesh bags, and washed with fresh water from the front, back, left and right directions using a 1-inch water pipe pump. Clear water and no slime are preferred. After rotating and tightening the bag opening, the A method is used, and every 2 bags are placed in a foam box, 5-6 ice bottles (550ml) are added to the foam box, and the box is sealed and packed back to the land-based conservation facility. 4 cm according to 100 / m 2 The retrieved clams will be seeded in two conservation ponds (305#, 306#), and the survival rate after 2 months of cultivation is 99.14%.

[0039] On July 15, 2022, 120 mature individuals were randomly selected from the conservation pond (305#) for artificial population breeding, resulting in 38 million attached seedlings. After juvenile cultivation, seedling cultivation, and finished product cultivation, 20,000 were selected at 2.5 cm, and 250-500 / m 2 Cultivation in conservation pond (318#), the rest of the individuals are provided to the farmers, and no longer remain in the land-based conservation facilities.

[0040] II. Daily management of clam conservation (1) Normal water change: On March 6, 2022, at 7:00 am, 305# was found to have a transparency of >50 cm, and 50% of the water was changed, and the fertilizer was adjusted from the fertilizer unit; At 14:00, it was found that the transparency of 305# was >50 cm, and 50% of the water was changed again, and the fertilizer was adjusted from the fertilizer unit. Repeat this operation every day.

[0041] (2) Water is not clear water: 3 March 7:00 found 305 # water is not clear, transparency <30 cm, immediately change water, discharge 50% water, check the bottom sand surface when there is a sand text clam, judge the vitality; With ball shovel to remove the dead clam and its radius of about 2 cm of yellow sand to the collection bin on one side of the tool bucket; The ball shovel is disinfected in the 80-120 ppm potassium permanganate solution on the other side of the tool bucket and continues to clean the next dead clam. After cleaning, rinse the sand surface with a 1-inch water pump, and after the water is completely discharged, air dry for 0.5-1 h, then adjust the water to half the pool; The next day, adjust the water to half the pool, and then change the water according to the above water change rules until the normal water change.

[0042] (3) Green algae treatment: After finding green algae on the bottom sand surface and the pool wall, the seed bank is drained. A 100-mesh, 1-meter-long silk screen bag is used to collect the green algae discharged with the water to avoid flowing into the sewer. A solution of 500g trichloroisocyanuric acid (containing chlorine 30%) with a concentration of 80mg / L is used to spray on the bottom sand beach using a 20L volume sprayer. After spraying, dry for 2-3h, and then fill the seed bank with water to the normal breeding water level. The main consideration for green algae cleaning is the amount of green algae in the seed bank. Generally, green algae grows vigorously every 7-10 days, and repeated cleaning can control the growth of green algae in the seed bank without affecting the growth and gonadal development of clams.

[0043] (4) Sunshade treatment: A 2m-high steel frame is installed along the top of the seed bank. When the air temperature is >30℃, a sunshade net is laid on the steel frame to shade all the seed banks. During typhoon and strong wind, the sunshade net is rolled up to the sides of the steel frame, and then unrolled after the wind subsides.

[0044] (5) Rainy season management: If it rains heavily, use a 60cm spout to keep the water level of the seed bank at the same level as the top of the 60cm spout to ensure that a large amount of fresh water is automatically discharged. After the rain, the water body should be kept stable and avoid large discharge and large input.

[0045] (6) Wintering treatment: When the water temperature is continuously 10-15℃ for 5 days, the seed bank starts to clean the pool. On December 2, 2022, the weather was fine, and all the clams and bottom sand in the seed bank were scooped into plastic baskets with a hole diameter of 0.8-1cm. The sand was washed back into the pool with a water pump, and the clams, sandworms, and miscellaneous clams were left in the plastic baskets. After removing the sandworms, miscellaneous clams, and other materials, the clams were weighed and the basic data was recorded in the seed bank file. Then, according to the size and breeding density, the clams were re-seeded to the original seed bank. Before the clams were re-seeded, the bottom sand of the seed bank was re-flattened according to the laying principle, and the thickness of the original bottom sand was increased by 5cm to meet the needs of wintering. After all the work is completed, the water level is filled to the maximum, and the water is changed appropriately during wintering.

[0046] Through the collection and transportation of the original habitat of clam, the survival rate of the groups in Lujibi conservation in Rucheng, Guangxi Qinzhou, Liaoning Dandong was maintained at a high level, and the effect of Lujibi conservation was good. The specific situation is shown in Table 2.

[0047] Table 2, the survival rate of the original species in each conservation pool and the survival rate of Lujibi conservation (up to 2022.12.2)

[0048] In summary, the present application sets a set of clam Lujibi conservation system and clam conservation management method, first, through the construction of specific conservation land-based system to improve the efficiency of the necessary hardware, second, the collection, transportation and adaptive breeding of different germplasm resources of clam are the key material conditions to improve the efficiency of conservation, finally, through a series of targeted operations such as water change, green moss treatment, shading treatment, rain season management, overwintering treatment, etc. to ensure the long-term preservation of different germplasm resources of clam in the land-based facility, which provides guarantee for the establishment of clam living germplasm bank, and can provide source for new variety creation. The present application provides the possibility for the long-term preservation of these germplasm resources, and also provides the basis and effective method for the long-term preservation of clam germplasm resources.

[0049] The above is the preferred embodiment of the present application, it should be noted that for ordinary skilled in the art, without departing from the principles of the present application, can also make a number of improvements and refinements, these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A hard clam onshore broodstock system, characterized in that, The utility model relates to a kind of breeding method of clam, including seed preservation unit, fertilizer water unit and breeding tail water collection unit, the seed preservation unit is by several seed preservation pools side by side, the seed preservation pool is rectangular, pool bottom is laid with yellow sand, the bottom of the seed preservation pool is close to sewer and is provided with first drain, the yellow sand is inclined from top to bottom to first drain, first drain is equipped with separate first drain insertion tube connected; The fertilizer water unit includes two fertilizer water pools, which are bowl-shaped. One side of the fertilizer water pool is provided with a second drain, which is in communication with the external drain main channel. The fertilizer water pool is connected to the water inlet pipe of the seed preservation unit through a floating pump pipeline. The breeding tail water unit includes a sewer, which is in communication with the external drain main channel on one side. A gate is arranged at the end of the sewer and the connection of the external drain main channel. The sewer is in communication with the first drain of each seed preservation pool and the fertilizer water pool.

2. The hard clam land-based seed production system of claim 1, wherein, The first drain insertion tube has three length specifications: 20-30 cm for cleaning the surface of the seed preservation pool and the yellow sand bottom, 60-70 cm for use in the rainy season, and 80-90 cm for normal breeding.

3. The hard clam land-based seed production system of claim 1, wherein, A brick wall is arranged around the drain to prevent the loss of the bottom caused by the flow of yellow sand into the drain.

4. The hard clam land-based seed production system of claim 1, wherein, The breeding tail water unit also includes a PVC pipe, one end of which is in communication with the sewer, and the other end is arranged at the bottom of the fertilizer water pool. A second drain insertion tube is arranged on the PVC pipe. When the second drain and the gate are closed, a water body self-circulation is formed in the fertilizer water unit and the seed preservation unit.

5. The hard clam land-based seed production system of claim 1, wherein, The area of each fertilizer water pool is 3-4 mu. Fish, shrimp and crabs are mixedly bred in the fertilizer water pool.

6. A clam onshore broodstock management method, characterized by, The method includes the following steps: Translocation: The temperature difference between the original habitat and the seed preservation site is less than 5℃. The translocation is carried out in autumn when the temperature decreases. The collection of northern populations is completed before the local sea is closed. Transportation: The clams for translocation are packed with nylon mesh bags, the bag opening is tightly tied and forms a live buckle, and the package is sealed with a foam box and an ice bottle. Adaptive self-propagation: The translocated clams are adaptively bred in the seed preservation pool. The breeding density is distributed according to the size of the shell length. After overwintering, randomly select hundreds of clam individuals for reproduction in the first breeding season in the seed preservation site. Through artificial breeding, seed cultivation and finished product breeding, 10-20 thousand particles are reserved to construct the seed population of the translocated population. Water management: Observe the water transparency of the seed preservation pool every day. Drain the clear water from the seed preservation pool twice a day, with a water exchange rate of 50%. Then adjust the fertilizer water in the fertilizer water pool to ensure that the transparency is greater than 50 cm for more than 8 hours. Green algae management: The seed preservation pool is drained, 500g of trichloroisocyanuric acid (containing 30% chlorine) is prepared into a solution with a concentration of 80mg / L, and the solution is sprayed on the yellow sand surface of the bottom material by a sprayer. After spraying, dry exposure for 2-3 hours, and then fill the seed preservation pool with water to the normal breeding water level. Sunshade management: A 2m high steel frame is arranged along the top of the seed preservation pool. When the air temperature is greater than 30℃, a sunshade net is laid on the steel frame. When it is windy, the sunshade net is folded to the two sides of the steel frame, and then it is unfolded again. Rainy season management: Use a first drainage pipe with a length of 60-70cm and fill the water level in the seed preservation pond to be level with the upper edge of the first drainage pipe with a length of 60-70cm to ensure that a large amount of fresh water is automatically discharged in time and to keep the water body stable after heavy rain. Overwintering Management: When the water temperature is maintained at 10℃~15℃ for 5 consecutive days, choose a sunny day and shovel all the clams and bottom sand in the breeding pond into a plastic basket with a hole diameter of 0.8~1cm. Use a water pump to wash the remaining sand back into the pond. Leave the clams, sandworms, and other clams in the plastic basket. After removing the sandworms and other clams, weigh the clams and collect basic data to enter into the breeding file. Then, according to the shell length specifications and stocking density, re-seed the clams into the original breeding pond. Before re-seedling the clams, level the bottom sand of the breeding pond to meet the overwintering requirements and increase the thickness of the bottom sand by 5~6cm. After all the work is completed, fill the water to the maximum level and maintain daily water change management.

7. The clam onshore broodstock management method of claim 6, wherein, In step (3), the corresponding distribution of the culture density according to the shell length is as follows: 500-750 pieces / m for shell length of 1-2 cm 2 , 250-500 pieces / m for shell length of 2-3 cm 2 , 150-300 pieces / m for shell length of 3-4 cm 2 , and 100 pieces / m for shell length of more than 4 cm 2 .

8. The clam onshore broodstock management method of claim 6, wherein, In step (2), the specific steps of transportation include: packing the clams into bags weighing 40-50 jin each using nylon mesh bags, rinsing the nylon mesh bags with fresh water from four directions (front, back, left, and right) using a 1-inch water pipe pump until clear water comes out and there is no sticky residue, then tying them tightly, and transporting them in foam boxes and ice bottles.

9. The clam onshore broodstock management method of claim 6, wherein, In step (4), the specific steps for changing the water in the breeding pond include: using clean water and fertilized water in combination, adopting a gradual water change, and replacing 50% of the clean water in the breeding pond when the transparency of the water in the breeding pond is less than 30cm for more than 6 hours after a single water change, and observing the floating sand and death of clams on the beach. If no abnormality is found in the clams, the water transparency is maintained until it is greater than 50cm before changing the water again, gradually reaching a time when the transparency is greater than 50cm for no less than 8 hours per day.

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