JPH0728623B2 - Shellfish aquaculture plant - Google Patents

Description

TECHNICAL FIELD The present invention relates to a shellfish aquaculture plant, and more specifically,
The present invention relates to a shellfish aquaculture plant designed to reduce the damage caused by starfish on shellfish such as clams, red shells, and milk oysters.

[Technical background of the invention]

As a method for cultivating shellfish, non-compartmental sea surface culture is usually adopted, and is classified into the following three types depending on the type of shellfish to be cultivated.

Raft-type hanging method This method is a method in which a raft is floated on the surface of the sea, and an appressor with seeds is hung from the raft to culture, and it is used for aquaculture of shellfish such as oysters and pearl oysters.

Pile driving method This method is a method of raising a "soda crack" and culturing the "crack", and is usually used for culturing oysters and the like.

Ground seeding method This method is a method of seeding seedlings using the shallow sea surface and culturing depending on natural feed, and is used for culturing various shellfish such as clams, mussels and clams. .

All of these aquaculture methods are adopted in consideration of the ecology of shellfish for aquaculture.

By the way, when cultivating shellfish, the biggest problem is
It is the extermination of harmful enemies. The harmful organisms include those that directly prey on useful aquatic animals and cause damage, and those that deprive the habitat of the aquaculture target and food and interfere with the aquaculture. For example, there are many types of sea stars that prey on shellfish, and in particular, starfish (Asterias) cause a lot of damage to clams, clams, stink bugs, and the like.

Therefore, in order to cultivate shellfish, it is necessary to consider in advance the means for exterminating harmful enemies such as starfish. By the way, normally, stars such as starfish (Asterias) grow on the seabed, and the seabeds such as sandboxes and reefs are used as food, so in the case of the raft hanging method described above, It can be said that the damage caused by such enemies is small.

However, the raft hanging method is not suitable for aquaculture of shellfish such as clams, clams, and mussels. That is, for example, in the case of clams, these shellfish live in sandy and muddy areas having a water depth of 5 to 6 m from the areas exposed at low tide. Since many of the starfish, which are harmful enemies, usually live in the area, it is easy to encounter damages, and it is difficult to adopt the area as a farm. In addition to the starfish, carnivorous snails may also be harmful.

Therefore, in order to solve such damage in the case of culturing shellfish such as clams, clams, and stinks, it is preferable to prevent the entry of harmful enemies, but as of today, the method has not been found. Therefore, although sprinkling of granular lime may be performed, in general, the actual situation is to collect and remove with a mop or the like.

By the way, when cultivating shellfish, it is necessary to create an environment in which shellfish can easily inhabit like the fish reef, in addition to the above-mentioned extermination of harmful enemies. And, as the conditions, at least two points are required: to obtain the same environment as the habitat of shellfish and to feed appropriately.

Therefore, the present inventor has conducted various studies from the viewpoint of obtaining an environment satisfying such points, and as a result of facilitating the natural generation of algae etc. as a bait, it is easy to obtain an environment such as a sandbox with a steel plate. It has been found that it is preferable to obtain a farm bed. In other words, the steel culture bed is not exposed to the atmosphere, so it is less likely to rust, and it has the advantages that it is lighter in weight than structural reefs made of concrete blocks, has a great variety of structures, and has a good algae generation rate.

The present invention has been made in view of the above points, and an object of the present invention is to provide a shellfish aquaculture plant capable of preventing the entry of harmful enemies with a simple configuration.

Another object of the present invention is to provide a shellfish aquaculture plant that can prevent the entry of harmful enemies, easily naturally generate algae as a bait for shellfish, and have an easy facility. is there.

[Means for solving problems]

And, the shellfish aquaculture plant of the present invention as a means for achieving the above object, a gas layer such as air or nitrogen gas is interposed between the culture bed and the seabed, and the gas layer causes damage such as starfish. It is configured to prevent an enemy from climbing up (entering) the above-mentioned aquaculture floor.

In addition, the shellfish aquaculture plant of the present invention as a means for achieving the above-mentioned other object has a support, and a support for the support for forming a pseudo-environmental floor such as a sandbox on one or a plurality of upper and lower floors, a rocky place, etc. A box having an open lower surface is provided at a portion of the stanchion located below the aquaculture floor, and a gas such as air or nitrogen gas is injected into the box to surround the stanchion where the box is located. And a gas layer formed on the substrate.

Here, in the above configuration, the floors on the upper and lower floors are usually
It consists of upper, middle, and lower three-story floors, and natural stones and blocks are installed on the upper floor to create a pseudo-rocky area, where algae such as abalone and turban shells and algae such as green algae grow and grow on the middle floor and lower floor, respectively. Is constructed by laying sand with a thickness of about 10 to 30 cm so as to grow shellfish such as clams, mussels and milk oysters. In addition, if necessary, the three-dimensional aquaculture floor is formed of a steel material, and the three-dimensional aquaculture floor is arranged so as to be adjacent in a square shape, a cross shape, or a circular shape.

[Action]

Then, based on the above configuration, the shellfish aquaculture plant of the present invention, the diver preliminarily surveys the installation location in the inland sea such as the Seto Inland Sea, and level the installation location, and then carries the aquaculture floor to the installation location with a sea crane. After being lifted up by a crane, it will be submerged in water and lowered to the seabed for installation.

After the facility, algae adhere to and grow on the aquaculture bed where a sandbox or the like is formed, and the algae that have grown act as a natural feed for seedlings or juveniles for aquaculture.

Then, the gas layer of air or nitrogen gas (the box into which the gas is injected) prevents harmful enemies such as starfish from climbing to the aquaculture floor, and the aquaculture of the shellfish is performed in a preferable state.

〔Example〕

Embodiments embodying the present invention will be described below with reference to the drawings.

Here, FIGS. 1 to 7 show an embodiment of the present invention, FIG. 1 (a) is a side view, FIG. 1 (b) is an enlarged view of a main part of a column, and FIG. 1 (c). ) Is a vertical cross-sectional view of FIG. 1 (b), FIG. 2 is a plan view of the upper floor, FIG. 3 is a plan view of the middle floor (lower floor), and FIG.
FIG. 5 is a plan view showing an adjacent arrangement state, FIG. 5 is a side view showing the adjacent arrangement state, FIG. 6 is an explanatory diagram of an installation procedure, and FIG. 7 is a plan view showing another arrangement state.

The shellfish aquaculture plant of this embodiment is roughly described as follows: a basic concrete block 1 and a rectangular aquaculture floor 2a having a plurality of upper and lower stages.
It is composed of 2b and 2c and a gas injection box 3.

Basic concrete blocks 1, 1 are about 5, 5m long and wide
1m, height 1m, weight about 9,6t, with a hollow 1a in the center
Blocks having a concave cross section and arranged in parallel. Then, sand can be arranged in the depression 1a, if necessary. In addition, the protrusions (base parts) 1b located at the respective ends of the blocks 1 and 1 have columns 4 ...
・ Are erected in parallel. Here, the pillar 4, ...
A steel material having a length of about 4.5 m is used as a base material, and the base portion 1b of the block 1 is firmly erected and fixed to the base portion 1b by a bolt at a lower portion thereof. Then, the pillars 4, ... Support and fix the upper, middle, and lower tiered rectangular culture beds 2a, 2b, 2c.

The upper and lower tiered rectangular culture beds 2a, 2b, 2c are made of steel plates, and are horizontally fixed to the stanchions 4, ... at intervals of 2 m. And on the floor, rocks,
A sandbox etc. is formed. That is, natural stones and blocks are installed on the upper floor 2a to make it a pseudo rocky place, and the middle floor 2b and the lower floor
Reinforcing materials having a height of about 15 to 20 cm are erected on the periphery and other places of each of 2c to form a shallow rectangular box (container shape) formed in 9 divisions. Then, each section is laid with sand with a thickness of about 10 to 30 cm to form a pseudo sandbox. Here, the amount of sand used is usually about 3 tons. In addition, aquaculture floor (especially upper floor 2a,
If necessary, the middle floor 2b) 2 is provided with a lighting port 8 at the center thereof for considering the lighting of the lower-stage aquaculture floor. The lighting port is usually a cover member (a steel plate having a size that covers the lighting port is used) and is fixed to the aquaculture floor body by bolting or the like. Note that the lighting port 8 may be made of a transparent or semitransparent hard plastic plate or the like, if necessary.

It should be noted that the formation of a pseudo rocky place and a pseudo sandy place cannot be done by the joint work of mechanical force and divers even after the facility on the seabed, but in the work on the sea surface before it is submerged in the seabed, the sand is sunk while submersed in water with a sea crane. We also carry in and fill natural stones and blocks. As a result, by forming a pseudo sandbox, sinking it into the seabed, and fixing it by fixing it, it is possible to achieve work stability and labor saving.

And the foundation concrete blocks 1 and 1 and the columns 4
..Square aquaculture beds 2a, 2 with upper and lower stages supported via
The aqua reef consisting of b and 2c is a cubic reef with a length of 6, 3 m, a width of 5, 4 m, and a height of 6, 5 m, and the sides are in an open state 6, and seawater flows without sufficient resistance. Moreover, it is designed to be able to illuminate the light sufficiently.

The total weight is about 47,3t, and the breakdown is basic concrete blocks 1,1 for 19,2t, main body except basic concrete blocks 1,1,10t, sand and blocks 17,4t
Has become.

The box 3 is for preventing the starfish from climbing up, and has a structure in which the lower surface 3a is opened and a gas such as air or nitrogen gas is injected into the inside. That is, the box 3 is arranged on the columns 4, ... That connect the aquaculture floor 2c and the basic concrete block 1. Since the gas such as air contained in the box 3 is pressed by the seawater from the lower side, a gas layer 10 such as an air layer is formed in the box, in other words, in that portion,
The structure is such that the columns 4, ... Are covered with a gas such as air. Therefore, when it crawls downward from the pillars 4, ..., it comes into contact (collision) with the gas layer 10 without fail, and in the case of aquatic organisms, its upward movement is blocked at that location. It is like this. by the way,
If the gas inside the box is dissolved in seawater, it will be replenished. Further, it is obvious that the box 3 may be integrated with the support column 4 from the beginning. A sensor for detecting the remaining amount of gas may be arranged in the box 3, and the gas may be automatically supplied into the box by the detection of the sensor.

By the way, in order to install the above-mentioned cultured reef on the seabed of the inland sea,
Normally, the procedure is as follows, as schematically shown in FIG. That is, the installation location is determined in advance by a comprehensive survey such as a seabed survey and a water quality survey. When the installation location is determined, the seabed is leveled with a jet pump. And
After land leveling, 16 with a 30-30t sea crane as soon as possible.
The individual aquaculture reefs of this example are carried to the site, and the sand is carried with them.

Then, after hoisting the aquaculture reef with a sea crane, the sand for the lower floor 2c and the middle floor 2b is put into the conveyor while submerged in the water. By the way, the total weight in the air is about 47,3 tons as described above, but in water, it is reduced to about 28,9 tons, which makes the method possible. At the same time, a gas such as air is supplied / injected into the box 3 so that the gas is sufficiently present in the box 3.

In the above procedure, the divers will be installed in fixed positions one after another on the seabed, and 16 squares will be arranged side by side as shown in Fig. 4. The central void will be the fish swimming pool 7. The total area is about 924 m ² .

Next, to describe the action of the shellfish aquaculture plant of the present embodiment, the aquaculture reef is installed in an inland sea such as the Seto Inland Sea,
It weighs about 28 to 9 tons, is stable and stable in tidal currents, and does not come into contact with the atmosphere after being installed on the sea floor, so it works against rust. Then, algae such as green algae propagate on the steel portion of the basic concrete block 1, each floor 2a, 2b, 2c and the pillars 4, 4, ..., And also on natural stones and blocks on the upper floor 2a. . Therefore, algae and turban shells such as algae and shells on the artificial artificial sandbox floors 2b and 2c, red snails,
Shellfish, such as milky, are naturally cultivated. In addition, as for fish, rockfish, red sea bream, black sea bream, etc. gather and there is a swimming pool 8
It grows by eating algae, plankton, small fish or artificially fed food while freely swimming in the sea, etc., and the installation part of the aqua reef acts as a marine ranch.

Then, when a harmful enemy such as a starfish climbs up the columns 4, ... and tries to enter the aquaculture floor 2a, it comes into contact with a gas such as the air in the gas containing box 3 installed in the middle of the columns 4. , Crawling up the stanchion 4 is prevented, and the farm floor
It prevents entry into 2a and acts to reduce damage to shellfish. When gas such as air in the box 3 is dissolved in seawater, the gas is sequentially replenished so that the gas such as air and nitrogen gas always covers the columns 4 ,.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and it is obvious that the present invention can be modified and implemented without changing the gist of the present invention. Incidentally, the basic concrete block may be formed into a circular shape to form an aquaculture reef with a circular shape, and the installation and placement method may be circular or cross-shaped. It is also possible to enclose a three-dimensional aquaculture plant installed in a square, circular, or cross shape with a net 9 to form a pure aquaculture farm. In this case, there is an advantage that the flow of seawater is made gentle and the outflow of sand is reduced.

In addition, it is possible to freely increase the gap size between the floors of each floor to improve the workability of the diver and improve the lighting. In addition, crawling up of starfish and the like is also appropriately applied. Furthermore, as the box can hold gas such as air inside, if a harmful enemy such as a starfish attempts to enter the culture bed,
Obviously, other configurations may be used as long as they are in contact with the gas and can prevent further creeping.

Further, in the above-mentioned embodiments, the explanation has been made on the case where the aquaculture floor and the like are formed by the steel material (plate), but it is also possible to use the one formed by concrete, reinforced plastic or the like like the ordinary fishing reef. Is clear, and also
It may be configured to have one or four or more floors.

〔The invention's effect〕

As is clear from the above description, according to the shellfish aquaculture plant of the present invention, by interposing a layer of gas such as air and nitrogen gas between the seabed and aquaculture floor for aquaculture of shellfish, The presence of the gas will prevent harmful enemies such as starfish from climbing up to the aquaculture floor, and thus have an effect of reducing damage to shellfish by the harmful enemies.

Further, according to the shellfish aquaculture plant of the present invention, since the aquaculture floor is three-dimensionally formed, it has the effect of being able to deal with the natural environment of the inland sea such as the Seto Inland Sea and to use the ocean three-dimensionally. . Then, it can be an environmental reef of not only limited fish or shellfish but also various kinds of fish and shellfish.

Further, according to the shellfish aquaculture plant of the present invention, by using a steel culture bed as the aquaculture floor, it has an advantage that algae, which is a feed amount of the shellfish, easily attaches, and has advantages such as light weight for production and transportation. It also has the effect.

[Brief description of drawings]

1 to 7 show an embodiment of the present invention, FIG. 1 (a) is a side view, FIG. 1 (b) is an enlarged view of a main part of a supporting column, and FIG. Fig. 1 (b) is a vertical sectional view, Fig. 2 is a plan view of the upper floor, Fig. 3 is a plan view of the middle floor (lower floor), Fig. 4 is a plan view showing an adjacent arrangement state, and Fig. 5 is the same. FIG. 6 is a side view showing the adjacent arrangement state, FIG. 6 is an explanatory view of the installation procedure, and FIG. 7 is another plan view showing the arrangement state. 1 ... Basic concrete block, 1a ... Dimple, 2 ...
… Aquaculture beds, 2a, 2b, 2c …… Square aquaculture beds with upper and lower tiers, 3
…… Gas injection box, 4 …… Posts, 5 …… Sand, 6 ……
Open state part, 7 …… Swimming pool, 8 …… Daylight entrance, 9 …… Net,
10 …… Gas layer such as air

Claims (4)

[Claims] 1. A gas layer such as air or nitrogen gas is interposed between the aquaculture floor and the seabed, and the gas layer prevents a harmful enemy such as a starfish from climbing to the aquaculture floor. A shellfish aquaculture plant characterized by. 2. A portion which has a pillar and which supports a culture bed forming a pseudo-environmental floor such as a sandbox, a rocky area or the like on one or more upper and lower floors, and which is located below the culture bed in the pillar. To
A shellfish aquaculture plant, characterized in that a box having an open lower surface is provided, and a gas such as air or nitrogen gas is injected into the box to form a gas layer around the columns where the box is located. 3. Floors on the upper and lower floors are composed of upper, middle and lower three-tiered floors, and natural stones and blocks are installed on the upper floor to create a pseudo rocky place, and algae such as abalone and turban shells and algae such as green algae. 3. The shellfish aquaculture plant according to claim 2, wherein each of the middle floor and the lower floor is laid with sand with a thickness of about 10 to 30 cm so as to grow shellfish such as clams, red shells and milky shells. . 4. The aquaculture plant according to claim 2, wherein the three-dimensional aquaculture floor is made of steel and the three-dimensional aquaculture floor is adjacently arranged in a rectangular shape, a cross shape or a circular shape.