Artificial fish reef for rearing juvenile hexagrammos otakii and method for manufacturing the same

Abstract

The present application relates to a kind of artificial reefs for the conservation of onchocercus takii juvenile fish and its preparation method, belong to the field of fishery resources protection, the artificial reef is hollow step type, bottom opening and is provided with support foot and is inserted in seabed, the side of the bottom step structure of artificial reef is provided with dentiform structure, artificial reef top end and dentiform structure are made of limestone material, the top of the uppermost step of artificial reef is provided with top water-permeable hole, seaweed binding rope is set in each dentiform structure and artificial reef top end, artificial reef side is provided with internal and external through string side water-permeable hole;Artificial reef outer surface is fixed with algae spore.The device can play an attracting role to onchocercus takii adult fish, play a protective role to onchocercus takii juvenile fish, and is beneficial to the recovery of onchocercus takii natural resources.

Description

Technical Field

[0001] This invention belongs to the field of fishery resource protection, and specifically relates to an artificial reef for raising juvenile rockfish and its preparation method. Background Technology

[0002] Artificial reefs can improve the ecological environment of aquatic areas, forming a miniature artificial ecosystem that provides a good habitat for fish and other aquatic organisms, allowing them to forage, reproduce, and grow. Through the scientific construction of artificial reefs, the goal of protecting and increasing fishery resources can be achieved.

[0003] The large-scaled rockfish (Hexagrammus octopus) is a species of fish belonging to the family Hexagramidae in the order Scorpaeniformes. Commonly known as the yellow croaker, it is an important reef-dwelling economic fish species in the coastal waters of northern my country. However, in recent years, due to factors such as overfishing and habitat destruction, coupled with the fish's inherently low egg-bearing capacity and reproductive rate, the population of large-scaled rockfish has declined significantly.

[0004] Studies have shown that large seaweeds such as sea kelp attract a high concentration of juvenile rockfish, thus playing a role in conserving their resources. Furthermore, the combined use of large seaweeds and artificial reefs can effectively improve fish attraction. Artificial reefs provide ample shade for juvenile rockfish, while the large seaweed releases oxygen through photosynthesis and provides some food. Rockfish have slender, smooth bodies and a penchant for burrowing, and sea kelp, with its dense foliage and good concealment, provides sufficient space for juvenile rockfish.

[0005] However, existing artificial reefs are made of materials such as cement, which require a long time to release alkaline substances before algae can attach. Even after attaching, the algae may not grow vigorously enough to provide adequate shelter for juvenile rockfish, thus hindering the effective attraction and conservation of rockfish resources. Furthermore, herbivores such as sea urchins feed on the large algae on the reef surface, reducing the shaded area and decreasing the food source for algae. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide an artificial reef for the conservation of juvenile rockfish (Hexagrammos octopus) and its preparation method. The device described in the present invention can attract and protect juvenile rockfish, which is conducive to the recovery of rockfish resources.

[0007] This invention is achieved through the following technical solution:

[0008] An artificial reef for the conservation of juvenile rockfish (Hexagrammos davidii) is described. The artificial reef is hollow and stepped, with an opening at the bottom and supporting feet inserted into the seabed. The sides of the bottom stepped structure of the artificial reef have serrated structures. The top of the artificial reef and the serrated structures are made of limestone. The top of the uppermost step of the artificial reef has a top water-permeable hole. Seaweed binding ropes are installed on each serrated structure and the top of the artificial reef. The sides of the artificial reef have internal and external water-permeable holes. Algae spores are fixed on the outer surface of the artificial reef.

[0009] As one of the preferred embodiments, the side slope of the stepped structure is 80 degrees.

[0010] As one of the preferred embodiments, the steel slag accounts for 30% by mass, and the raw materials are soaked in acetic acid for more than 3 hours before use.

[0011] As one of the preferred embodiments, the artificial reef is a two-layer hollow stepped structure.

[0012] As one of the preferred embodiments, two rows of toothed structures are provided only on the side of the bottom step structure.

[0013] As one of the preferred embodiments, large algae, including 70-80% sea buckthorn, kelp, and wakame, are bound to the serrated structure and the top of the artificial reef.

[0014] The present invention also provides a method for preparing the artificial reef, wherein the main body of the artificial reef is composed of steel slag and concrete, and a toothed structure and a top are made of limestone on the outer surface of the main body. Binding ropes are set on the toothed structure and the top. Then, cell solidification technology is used to fix algal spores on the surface of the artificial reef to improve the germination rate of spores and promote the formation of large algal forests in the later stage.

[0015] As one of the preferred embodiments, alkaline waste steel slag is soaked in acetic acid solution to release toxic substances, and then used to make the main structure of the artificial reef.

[0016] As one of the preferred embodiments, the cell solidification technology involves uniformly applying a mixture of alginate and algal spore fertilized eggs onto the surface of the reef, followed by applying a layer of calcium chloride solution.

[0017] As one of the preferred embodiments, 70-80% of the algal spores are sea spores, and also include kelp and wakame.

[0018] The beneficial effects of this invention compared to the prior art are as follows:

[0019] This invention adopts a stepped main structure and sets a toothed structure on the outer surface of the main structure. Large algae binding ropes, mainly sea spores, are set on the top of the artificial reef and the toothed structure. At the same time, algae spores, mainly sea spores, are fixed on the outer surface of the artificial reef, so that sea spores can grow into the dominant algae of the artificial reef and attract juvenile rockfish to gather there.

[0020] After the artificial reef is made, it is first soaked in sodium alginate solution and then in calcium chloride solution to fix the spores of sea spores, which can improve the germination rate of sea spores and promote their subsequent growth.

[0021] This invention features a hollow, stepped main body that provides ample shelter for juvenile rockfish, allowing them to inhabit the habitat. The bottom opening and supporting feet facilitate feeding on benthic organisms and provide protection from predators. The attached large seaweed not only provides shade but also serves as a food source for the juvenile rockfish.

[0022] The side of each stepped structure of this invention is steeply sloped and has a serrated structure, which can increase the attachment area for large seaweed and effectively prevent sea urchins from consuming the seaweed.

[0023] This invention uses steel slag as a raw material to supplement calcium and iron, creating a marine forest design. Before deploying the algae onto the reef, cell solidification technology is used to fix the spores of large algae such as sea urchins onto the reef surface. This allows the large algae to grow and reproduce well on the reef. The toothed structure and limestone apex promote the oxygen release rate of the algae, which is beneficial to the survival of juvenile fish.

[0024] This invention relates to an artificial reef with top and side permeable holes, ensuring water exchange between the inside and outside of the reef and facilitating the entry and exit of juvenile fish, while preventing threats from predators and competitors. Cell fixation technology allows large algae to grow well on the reef surface; however, because it takes time for the fixed algal spores to mature, the initial attraction rate upon reef deployment is not high. Therefore, binding large seaweed increases the attraction rate of juvenile fish immediately after reef deployment. The large seaweed used for cell fixation and binding is mainly *Gnaphalium affine*, but kelp, wakame, and other large seaweed can also be bound, combining them to improve the attraction effect on juvenile *Hexagrammos otakii*. *Hexagrammos otakii* also feeds on various types of seaweed; binding and fixing various large seaweeds in combination with the artificial reef provides them with abundant food and greater hiding space. Attached Figure Description

[0025] Figure 1 This is a front view of one side of the artificial reef of the present invention;

[0026] Figure 2 This is a top view of the artificial reef of the present invention;

[0027] 1. Supporting feet, 2. Toothed structure, 3. Top, 4. Top water permeable hole, 5. Side water permeable hole, 6. Side, 7. Vertical water passage hole. Detailed Implementation

[0028] The technical solution of the present invention will be further explained below through embodiments, but the scope of protection of the present invention is not limited in any way by the embodiments.

[0029] Example 1

[0030] An artificial reef for conserving juvenile rockfish, such as Figure 1-2 As shown, the artificial reef is hollow and stepped, with an opening at the bottom and a supporting foot 1 inserted into the seabed. The bottom step structure of the artificial reef has a toothed structure 2 on its side. The top of the artificial reef 3 and the toothed structure are made of limestone. The top of the uppermost step of the artificial reef has a top water permeable hole 4. Seaweed binding ropes are set on each toothed structure and the top of the artificial reef. The sides of the artificial reef have side water permeable holes 5 that run through the inside and outside. Algae spores are fixed on the outer surface of the artificial reef.

[0031] As one of the preferred embodiments, the side slope of the stepped structure is 80 degrees.

[0032] As one of the preferred embodiments, the steel slag accounts for 30% by mass, and the raw materials are soaked in acetic acid for more than 3 hours before use.

[0033] As one of the preferred embodiments, the artificial reef is a two-layer hollow stepped structure, with vertical water passage holes 7 provided on the side of the upper stepped structure.

[0034] As one of the preferred embodiments, two rows of toothed structures are provided only on the side of the bottom step structure.

[0035] As one of the preferred embodiments, the large algae tied to the toothed structure and the top of the artificial reef include sea buckthorn with a coverage of 70-80%, as well as kelp and wakame, which can better attract juvenile rockfish.

[0036] The artificial reef is constructed by stacking two hollow stepped structures. The bottom stepped structure has an opening at the bottom and supporting feet on the side. These supporting feet are inserted into the seabed for stability and allow for water and air permeability, facilitating water exchange and the free movement of aquatic organisms inside and outside the artificial reef. Two rows of toothed structures are located on the lower side of the bottom stepped structure to bind large algae and prevent sea urchins from climbing onto the artificial reef to feed on algae. The upper part of the bottom stepped structure has two side permeable holes, and the upper stepped structure has vertical permeable holes on its side. The top of the upper stepped structure has a top permeable hole and binding ropes. The main body of the artificial reef is composed of steel slag and concrete. Limestone is used to create toothed structures and a top edge on the outer surface of the main body, with binding ropes attached to these toothed structures and the top edge. Cell solidification technology is then used to fix algal spores to the reef surface to improve spore germination rate and promote the formation of large algal forests later.

[0037] A more specific preparation method: First, waste steel slag from factories is used as raw material. The raw material is soaked in acetic acid for at least 3 hours to effectively remove toxic substances and prevent expansion, thus improving the recycling efficiency of the steel slag. High-concentration industrial acetic acid is used, diluted to obtain a 10%–15% acetic acid solution, which effectively neutralizes the acidity or alkalinity of the raw material. The mass ratio of steel slag to concrete is set at 3:7, providing abundant calcium and iron elements for organisms and effectively ensuring the stability of the reef and its fish-attracting effect. Two layers of regular pentagonal frustum are constructed using the treated steel slag and concrete, decreasing in size from bottom to top, with a side slope of 80 degrees for the stepped structure.

[0038] The cell solidification technology mainly involves mixing 4% alginic acid with fertilized eggs of sea bream, kelp, and wakame at a 1:1 volume ratio. The reef is then soaked in seawater and dried. The prepared solution is then evenly applied to the reef surface, followed by a layer of calcium chloride solution as a solidification coating. Because the algal cells are encapsulated, they are effectively protected from adverse environmental influences. The encapsulation layer slowly dissolves upon contact with cations (sodium ions) in the seawater, allowing the algae to grow rapidly. The surrounding calcium carbonate structure provides calcium for algal development, promoting photosynthesis and growth, and providing a suitable habitat for juvenile fish.

[0039] Because of the use of cell solidification technology, algae growth takes a certain amount of time, which affects the fish-attracting effect of the artificial reef. By binding large seaweeds such as sea urchins, the fish-attracting effect of the initial artificial reef can be effectively improved. The material and complex structure of the reef, as well as the attachment of algae, can provide a wide living space for juvenile rockfish, allowing them to feed, avoid predators, and inhabit.

[0040] When the artificial reef of this embodiment is deployed to a suitable natural sea area, after about a month of development, the algal fertilized eggs on the surface of the artificial reef will germinate into sea worm seedlings, and at the same time, the sea worms will be bound to the tooth-like structure. After about a year of growth, the algae on the artificial reef will grow luxuriantly and form a colony of juvenile and adult rockfish, which can effectively conserve rockfish resources.

Claims

1. A method for preparing an artificial reef for raising juvenile Hexagrammos oysterfish, characterized in that, The artificial reef features a hollow, stepped main body, providing ample shelter for juvenile rockfish. The main body is constructed from steel slag and concrete. The alkaline waste steel slag is soaked in an acetic acid solution for over 3 hours to release toxic substances before being used to create the main structure. The mass ratio of steel slag to concrete is set at 3:

7. Two hollow pentagonal frustums are constructed, decreasing in size from bottom to top, with an 80-degree side slope. Each step structure features a steep slope and a serrated structure to increase the attachment area for large seaweed and effectively prevent sea urchins from consuming the seaweed. The artificial reef has an opening at the bottom and is equipped with supporting feet inserted into the seabed to facilitate water flow and provide shelter for juvenile fish. The sides of the bottom stepped structure of the artificial reef have two rows of tooth-like structures, which are arranged around the circumference of the platform. The top of the artificial reef and the tooth-like structures are made of limestone. The top of the uppermost step of the artificial reef has a top water permeable hole. Seaweed binding ropes are installed on each tooth-like structure and the top of the artificial reef. The sides of the artificial reef have side water permeable holes that run through the inside and outside. The artificial reef is equipped with top and side water permeable holes to ensure water exchange between the inside and outside of the artificial reef and the entry and exit of juvenile fish, while preventing threats from predators and competitors. After the artificial reef is made, it is first soaked in sodium alginate solution and then in calcium chloride solution to fix the spores of sea spores, which can improve the germination rate of sea spores and promote their subsequent growth. Then, cell solidification technology is used to fix the algal spores, mainly sea spores, on the surface of the artificial reef to improve the germination rate of the spores and promote the formation of large algal forests in the later stage. This allows sea spores to grow into the dominant algae of the artificial reef, attracting juvenile rockfish to gather here. The cell solidification technology involves mixing 4% alginate with algal spore fertilized eggs at a 1:1 volume ratio, applying the mixture evenly to the surface of the artificial reef, and then applying a layer of calcium chloride solution. The method involves deploying artificial reefs in suitable natural sea areas. Fertilized algal eggs on the surface of the artificial reefs germinate into sea slug larvae. Simultaneously, large algae are bound to the tooth-like structures and the top of the artificial reefs to form an artificial algal field. The large algae include sea slugs, kelp, and wakame, with the amount of sea slugs exceeding that of kelp and wakame. The bound large algae provide shade and also serve as a food source for juvenile rockfish. The algae on the artificial reefs grow densely, forming a colony of juvenile rockfish.

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