JP2003158942A - Oxygen supply apparatus and method for cultured shells - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oxygen supply apparatus for cultured shells, capable of easily increasing an amount of dissolved oxygen in bottom water so as to promote growth of the shells cultured in the bottom water, simple and economical, and to provide a oxygen supplying method for the cultured shells. <P>SOLUTION: This oxygen supply apparatus for the cultured shells is attached to a raft 7 for culturing the shells and supplies the oxygen to the shells mainly positioned in a bottom part L of the raft 7 so as to promote the growth of the shells, wherein the apparatus is composed of a water conducting pipe 1, a water supply propeller 2, and a bottom plate guide 3, so that the water conducting pipe 1 is fastened to the raft 7 and equipped with a water intake 1a which takes surface water therein at its top and a bottom end which is extended into a bottom portion of the shells positioned in the bottom part L, the water supply propeller 2 is positioned at the bottom end of the inside of the water conducting pipe 1 and vigorously conducts the surface water existing in the water conducting pipe 1 in the downward direction, and the bottom plate guide 3 is positioned just below the water conducting pipe 1 and horizontally spreads the surface water supplied from the water conducting pipe 1 by making the water beat against itself. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to seawater (surface water) of a surface layer portion having a large amount of dissolved oxygen, which is attached to an aquaculture raft for cultivating shellfish such as oysters, pearl oysters or scallops.
TECHNICAL FIELD The present invention relates to an oxygen supply device for cultured shellfish and an oxygen supply method for cultured shellfish, which can be supplied to the bottom layer having a small amount of dissolved oxygen to promote the growth of shellfish.

[0002]

2. Description of the Related Art It is known that when culturing shellfish such as oysters and pearl oysters, the supply of oxygen promotes their growth. Conventionally, for example, the following exist as an oxygen supply means when culturing such shellfish using a raft. 1. A hose is connected to a compressor installed on a ship or raft, and at the tip of the hose, a box containing a rotary blade that mixes and stirs water and compressed air is installed, and there are many nozzles with fine holes on the box surface. Attach it, hang it in water, and jet it. 2. A hose is connected to a compressor installed on a ship or raft, and a water pipe with numerous holes is attached to the end of the hose to hang it in water, and a separate submersible pump collects seawater from the surface layer. , Compressed air and surface water are mixed and aerated and diffused in water.

[0003]

However, in these means, since the mixture of oxygen and seawater is injected by the compressor provided on the ship, raft, etc., the bubbles are 2 to 3 mm.
Since it is not so small (10 to 20 μm or less) as it dissolves in seawater, and the ejection pressure is weak, it is impossible to sufficiently promote the growth of shellfish. In order to promote the healthy growth of shellfish, the amount of oxygen contained in seawater (dissolved oxygen amount) is required to be at least 3 mg / L. Usually, the dissolved oxygen content of surface water is 10 mg / L, and that of middle layer water of a depth of about 4 m is 4 mg / L. Therefore, even by conventional means, the growth of shellfish cultivated by these surface water and middle layer water is not possible. To some extent promoted. However, the amount of dissolved oxygen in bottom layer water having a depth of about 8 m is as small as 2 mg / L or less, and the amount of dissolved oxygen cannot be effectively increased by conventional means.

It is possible to increase the amount of dissolved oxygen in the bottom layer water (seawater in the bottom layer) by using a large compressor or a large number of compressors, but this would make the equipment bulky and uneconomical. Is.

Therefore, an object of the present invention is to easily increase the amount of dissolved oxygen in the bottom layer water to promote the growth of shellfish cultivated in the bottom layer water, which is simple and economical. A supply device and an oxygen supply method are provided.

[0006]

In order to achieve the above object, the oxygen supply device for aquaculture shellfish according to claim 1 of the present invention is attached to a raft (7) for aquaculture of shellfish, which is mainly a bottom layer portion. A device for supplying oxygen to shellfish (K) located in (L) to promote its growth, the device being fixed to the raft (7) and having an intake part (1a) for taking in surface water at the upper end. , Shellfish (K) whose lower end is located in the bottom layer (L)
Of the water guiding pipe (1) reaching the lower part of the water guiding pipe (1) and the surface water in the water guiding pipe (1) introduced from the water intake part (1a) provided at the lower end of the water guiding pipe (1) vigorously downward. A water supply propeller (2) for sending, and a bottom plate guide (3) provided immediately below the water pipe (1) so that surface water supplied from the water pipe (1) hits and diffuses horizontally. It is characterized by

Further, in the oxygen supply device for cultured shellfish according to a second aspect of the present invention, a tubular body (4) for sending high pressure water is provided at the upper end of the water guiding pipe (1), and the tubular body (4) is provided. The air suction cylinder (5) for supplying the outside air is connected to the lower end portion.

Further, the oxygen supply device for cultured shellfish according to a third aspect of the present invention is characterized in that the bottom plate guide (3) is detachable.

In the oxygen supply device for cultured shellfish according to a fourth aspect of the present invention, the bottom plate guide (3) is replaced with an upper end portion,
An injector (6) provided with an opening (6a) communicating with the water guiding pipe (1) and a projecting cylinder (6b) for horizontally injecting the surface water flowing from the opening (6a). Is provided.

Still further, in the method for feeding oxygen to cultured shellfish according to claim 5, in the raft (7) for shellfish culture, oxygen is supplied mainly to the shellfish (K) located in the bottom layer (L). A method for promoting growth, comprising the raft (7),
The water guide pipe (1) is fixed to the upper end part, which has a water intake part (1a) for taking in surface water, and the lower end part reaches the lower part of the shellfish (K) located in the bottom layer part (L). A water supply propeller (2) is provided at the lower end of the inside to forcefully send the surface water in the water guiding pipe (1) taken from the water intake portion (1a) downward, and at the same time, the water guiding pipe (1). ) Bottom plate guide (3)
Is provided so that surface water supplied from the water guiding pipe (1) hits and diffuses in the horizontal direction.

Further, in the method for supplying oxygen-cultured cultured shellfish according to a sixth aspect of the present invention, the silicic acid solution is introduced into the water pipe (1) and the diatom solution is fed downward together with the surface water. Characterized by breeding.

Symbols in parentheses indicate corresponding elements or corresponding matters described in the drawings and embodiments of the invention described later.

According to the oxygen supply device for cultured shellfish according to the first aspect of the present invention, the shellfish is fixed to the raft and has the water intake portion for taking in surface water at the upper end and the lower end for the shellfish. A water pipe that reaches a lower level, a water propeller that is provided at the lower end of the water pipe to send surface water in the water pipe downward, and a surface water that is provided directly below the water pipe. Since it is provided with a bottom plate guide adapted to be diffused in the horizontal direction by hitting, the dissolved oxygen contained in the surface water in large amount can be effectively supplied to the bottom layer portion. Therefore, the growth of the shellfish located in the bottom layer can be promoted.

By sending the surface water to the bottom layer, the plankton which causes red tide such as heterocapsa that inhabits the surface layer in large amounts can also be sent to the bottom layer. Since the dissolved oxygen content of the bottom water is smaller than that of the surface water, the growth of Heterocapsa and the like is suppressed. This allows
Can protect shellfish from red tide damage.

Since the water-propelling propeller is provided especially at the lower end of the water pipe, surface water can be sent as a rotary swirl flow to a farther distance, and oxygen can be supplied over a wide range of the bottom layer. By the way, if this water delivery propeller is installed at the upper end of the water guiding pipe, the flow velocity in the water guiding pipe will decrease, and when it is discharged from the water guiding pipe, it will receive hydraulic resistance, so as with the case of sending with a conventional compressor,
I can't send far.

Further, since this oxygen supply device is formed by the water guide pipe, the water supply propeller and the bottom plate guide, the structure is simple and the economy is excellent.

According to the invention of claim 2, claim 1
In addition to the function and effect of the invention described in (1), a cylinder for sending high-pressure water is provided at the upper end of the water guide pipe, and an air suction cylinder for supplying outside air is connected to the lower end of the cylinder. The surface water and the outside air can be mixed by the pressure of the high-pressure water and effectively supplied to the bottom layer. This allows more oxygen to be delivered to the bottom layer. At this time, the bubbles of oxygen sent to the bottom layer are so small (10 to 20 μm or less) that they are dissolved in seawater.

According to the invention described in claim 3, in addition to the effect of the invention described in claim 1 or 2, since the bottom plate guide is detachable, the surface layer can be removed by removing the bottom plate guide. Water etc. can be applied to the seabed to remove the sludge existing there. This is effective, for example, because microorganisms and the like harmful to shellfish can be eliminated if it is carried out before the culture of shellfish is started.

Further, according to the invention of claim 4,
In addition to the invention described in claim 1 or 2, the upper end portion is provided with an opening communicating with the water guiding pipe, and an injection cylinder portion for horizontally injecting the surface water flowing in from the opening is projected. Since the body is provided, surface water or the like can be supplied to a long distance by this injection cylinder portion. Therefore, the amount of dissolved oxygen in the bottom layer portion can be effectively increased over a wide range.

Further, according to the invention described in claim 5, it is possible to effectively supply the dissolved oxygen contained in the surface water to the bottom layer. Therefore, the growth of the shellfish located in the bottom layer can be promoted.

According to the invention described in claim 6, in addition to the effect of the invention described in claim 5, the silicic acid solution is introduced into the water pipe, and the silicic acid solution is lowered together with the surface water. The silicate solution is supplied to seawater so that diatoms (plankton) can be propagated.
This diatom has an extremely fast growth rate and promptly consumes nutrients in seawater. Therefore, heterocapsa (red tide) causes nutrition competition and suppresses growth. This can protect shellfish from red tide damage.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION With reference to FIG. 1, an oxygen supply device for cultured shellfish according to a first embodiment of the present invention will be described. FIG. 1 is a perspective view showing an oxygen supply device. The length of the water guiding pipe in this device is about 7 m, and the amount of surface water discharged from the lower end thereof is 6.6 tons per minute.
Further, the surface water sent by this device diffuses in the bottom layer L to the extent that it exceeds the size of the raft (10 m × 20 m). The shaded portion in the figure indicates the photosynthetic depth region where the dissolved oxygen amount is large, and the lower portion indicates the photosynthesis impossible depth region where the dissolved oxygen amount is small.

The oxygen supply device for aquaculture shellfish according to the first embodiment of the present invention is attached to the raft 7 for oyster culture, and supplies oxygen to the oyster K mainly located in the bottom layer L to promote its growth. It is a water transfer pipe 1, a water propeller 2
And a bottom plate guide 3.

The water guide pipe 1 is fixed to the center of the raft 7, has an intake part 1a for taking in surface water at the upper end, and has a length where the lower end reaches the lower part of the oyster K located in the bottom layer L. . The water-propelling propeller 2 is provided at the lower end of the water guiding pipe 1, and vigorously sends the surface water in the water guiding pipe 1 taken from the water intake portion 1a downward. Also,
The bottom plate guide 3 is provided directly below the water guiding pipe 1 and is fixed to the water guiding pipe 1 by a support plate 3a. The bottom plate guide 3 is provided so that surface water supplied from the water guiding pipe 1 hits and diffuses, and the direction thereof is changed to a horizontal direction. ing.

This oxygen supply device operates as follows.
First, before the operation, the inside of the water conduit 1 is in a state of being filled with the surface water flowing from the water intake portion 1a.
When the water propeller 2 is rotated from this state, the surface water in the water guide pipe 1 is vigorously sent downward by the rotational force thereof, and hits the bottom plate guide 3 located immediately below it to be sent horizontally. At this time, new surface water sequentially flows into the water conduit 1 from the water intake 1a.

The surface water sent in the horizontal direction reaches every corner of the bottom layer portion L where the oyster K is located, and supplies the bottom layer portion L with oxygen rich in the surface water. by this,
The amount of dissolved oxygen in the bottom water increases, which is necessary for aquaculture of oyster K. 3
It is more than mg / L and promotes the growth of oyster K.

In addition, this oxygen supply device is equipped with a water pipe 1.
Since it is formed by the water supply propeller 2 and the bottom plate guide 3,
The structure is simple, the manufacturing cost and maintenance cost are low, and the economy is excellent.

The inventors of the present invention conducted an experiment to test the effect of this device. This test is for water propeller 2
The apparatus of the present invention using a stirring amount of 6.6 m ³ / min was attached to the raft 7 and driven, and the dissolved oxygen amount at each water depth was measured at a position away from the water pipe 1.

The device of the present invention was attached to the raft 7 and driven for 5 minutes, and the result of measurement at a position 1 m away from the water pipe 1 was as follows:
The amount of dissolved oxygen at a depth of 8 m, which is the bottom layer L, is 2.31.
mg / L to 6.60 mg / L, and also from the bottom layer L at a water depth of 7 m, 2.20 mg / L to 4.30 m
g / L, respectively. It should be noted that at a water depth of 5 m which is the middle layer portion M, it remains 4.60 mg / L, and is almost equal to the surface layer portion H
At a water depth of 2 m, 10.25 mg / L to 10.00
It was changed to mg / L.

Further, the device of the present invention was attached to the raft 7 and driven for 60 minutes, and measured at a position 5 m away from the water guiding pipe 1, and as a result, the dissolved oxygen amount at the water depth of 8 m which is the bottom layer L was 2.
5 mg / L to 4.13 mg / L, and 3 mg / L to 4.55 mg / L at a water depth of 7 m, which is also the bottom layer L
Each increased to L. In addition, the water depth of the middle layer M is 5 m
Then, it changed from 4.3 mg / L to 5.95 mg / L.

From this experiment, it was confirmed that when the apparatus of the present invention was used, the amount of dissolved oxygen in the bottom layer L greatly exceeded the numerical value (3 mg / L) required for cultivating the oyster K.

An oxygen supply device for cultured shellfish according to a second embodiment of the present invention will be described with reference to FIGS. 2 to 4. FIG. 2 is a front view showing a state where the oxygen supply device is provided on the raft 7. FIG. 3 is a front view showing this oxygen supply device, FIG. 4 (a) is a partially enlarged front view thereof, and FIG. 4 (b) is a sectional view taken along line AA of FIG. 4 (a).

The characteristic of this device is that a cylinder 4 for sending high-pressure water is provided at the upper end of the water guide pipe 1, and an air suction cylinder 5 for supplying outside air is connected to the lower end of the cylinder 4. is there. The uppermost end of the water guiding pipe 1 and the upper ends of the tubular body 4 and the air suction tube 5 project upward from the sea surface S.
When high-pressure water is sent from the tubular body 4 into the water guide pipe 1, the outside air flows in from the air intake tube 5 by its suction action. Also,
The surface water in the water pipe 1 is more strongly sent downward by the pressure, and after hitting the bottom plate guide 3, spreads over a wider area. Therefore, oxygen in the outside air and oxygen in the surface water are abundantly supplied to the bottom layer L, and the growth of the oyster K is very smoothly promoted. At this time, the bubbles of oxygen sent to the bottom layer L are extremely small (10 to 20 μm or less) as they are dissolved in seawater.
It has become. As the high-pressure water, it is preferable to use surface water having a large amount of dissolved oxygen.

The bottom plate guide 3 can be detached from the water pipe 1. When the water feed propeller 2 is rotated with the bottom plate guide 3 removed, the surface water hits the sludge D on the seabed and scatters and removes the sludge D.
As a result, the seabed where the raft 7 is located can be cleaned, and the growth of oyster K can be promoted.

With reference to FIG. 5, an oxygen supply device for cultured shellfish according to a third embodiment of the present invention will be described. Figure 5
FIG. 5A is a front view showing the oxygen supply device, and FIG.
FIG. 6 is a sectional view taken along line BB in FIG.

The feature of this oxygen supply device is that the bottom plate guide 3
Instead of the above, the injector 6 is provided. This injector 6
Has an opening 6a at its upper end communicating with the water conduit 1.
In addition, four injection cylinders 6b for horizontally injecting the surface water flowing from the opening 6a are provided at equal intervals. Therefore, the surface water sent downward by the water delivery propeller 2 has its momentum maintained because the jetting direction is limited by the jetting cylinder portion 6b, and reaches farther than in the case of the bottom plate guide 3. Thereby, the amount of dissolved oxygen in the bottom layer portion L can be increased over a wide range. Although four injection cylinders 6b are provided here, the number of injection cylinders 6b is not limited to this, and for example, one injection cylinder 6b may be extended to a desired position.

Incidentally, in any of the oxygen supply devices according to the first to third embodiments, the water pipe 1 thereof is provided.
Can be used not only for feeding surface water and the like, but also for introducing a silicic acid solution. This is a method of supplying oxygen to the shellfish K located mainly in the bottom layer part L of the raft 7 to promote its growth, and the raft 7 has an intake part 1a for taking in surface water at the upper end, Bottom end is bottom layer L
The water transfer pipe 1 reaching the lower level of the shellfish K located at is fixed, and a water propeller 2 is provided at the lower end of the water transfer pipe 1 so that the surface water in the water transfer pipe 1 taken from the water intake part 1a is vigorously downwards. In the aquaculture shellfish oxygen-supplying method in which the bottom plate guide 3 is provided immediately below the water guiding pipe 1 so that the surface water supplied from the water guiding pipe 1 hits and diffuses horizontally, This is a method in which a silicic acid solution is added and the silicic acid solution is sent downward together with the surface water. As described above, by supplying the silicic acid solution and supplying it to the seawater, the diatom can be grown and the growth of the heterocapsa which is the cause of the red tide can be suppressed, and the oyster K can be protected from the damage of the heterocapsa.

[0038]

According to the oxygen supply device for cultured shellfish according to the first aspect of the present invention, it is possible to effectively supply the dissolved oxygen contained in the surface water abundantly and abundant plankton due to photosynthesis to the bottom layer. . Therefore, the growth of the shellfish located in the bottom layer can be promoted. Moreover, since this oxygen supply device is formed of the water guide pipe, the water supply propeller, and the bottom plate guide, it has a simple structure and is excellent in economic efficiency.

According to the second aspect of the present invention, in addition to the effect of the first aspect of the invention, since the tubular body and the air intake tube are provided at the upper end portion of the water guiding pipe, the high pressure water is provided. The surface water and the outside air can be effectively supplied to the bottom layer by the pressure. As a result, more oxygen can be sent to the bottom layer, and the growth of shellfish can be further promoted.

Further, according to the invention of claim 3,
In addition to the effect of the invention described in claim 1 or 2, since the bottom plate guide is detachable, surface water or the like can be applied to the seabed to remove the sludge present therein. As a result, microorganisms harmful to shellfish can be eliminated and their growth can be promoted.

Further, according to the invention described in claim 4, in addition to the invention described in claim 1 or 2, since an injector is provided, surface water or the like can be supplied to a long distance by the injection cylinder portion. You can As a result, the amount of dissolved oxygen in the bottom layer can be effectively increased over a wide range, and the growth of shellfish can be promoted over a wide range.

Further, according to the invention described in claim 5, it is possible to effectively supply the dissolved oxygen contained in the surface water to the bottom layer. Therefore, the growth of the shellfish located in the bottom layer can be promoted.

According to the invention described in claim 6, in addition to the effect of the invention described in claim 5, the silicic acid solution is introduced into the water pipe, and the silicic acid solution is discharged downward together with the surface water. Since the silicate solution is supplied to seawater to propagate diatoms, shellfish can be protected from damage from red tide and their growth can be further promoted.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of an oxygen supply device according to the present invention.

FIG. 2 shows a second embodiment of an oxygen supply device according to the present invention,
It is a front view which shows the state attached to the raft.

FIG. 3 is a front view showing the device shown in FIG.

4A and 4B show the apparatus shown in FIG. 2, in which FIG. 4A is a partially enlarged front view, and FIG. 4B is a sectional view taken along line AA in FIG.

5A and 5B show a third embodiment of the oxygen supply device according to the present invention, wherein FIG. 5A is a front view, and FIG. 5B is B in FIG.
It is a -B line sectional view.

[Explanation of symbols]

1 Water pipe 1a Water intake 2 Water propeller 3 Bottom plate guide 3a Support plate 4 cylinder 5 Air suction cylinder 6 injectors 6a opening 6b Injection cylinder 7 raft D sludge H surface layer K shellfish (oyster) L bottom layer M Middle part S sea level

Claims (6)

[Claims] 1. A device which is attached to a raft for shellfish culture and which mainly supplies oxygen to shellfish located in the bottom layer to promote the growth thereof, which is fixed to the raft and takes in surface water at the upper end. With a water intake part, the lower end of the water transfer pipe reaching the lower part of the shellfish located in the bottom layer part, and the surface water in the water transfer pipe provided at the lower end part of the water transfer part, taken in from the water intake part Oxygen for aquaculture shells, which is equipped with a water-propelling propeller for vigorously sending water to the water, and a bottom plate guide that is provided immediately below the water-conducting pipe so that surface water supplied from the water-conducting pipe hits and diffuses horizontally. Supply device. 2. A cylinder for sending high-pressure water is provided at an upper end of the water guide pipe, and an air suction cylinder for supplying outside air is connected to a lower end of the cylinder.
The oxygen supply device for aquaculture shellfish described in. 3. The oxygen supply device for aquaculture shellfish according to claim 1, wherein the bottom plate guide is detachable. 4. An injection method in which, instead of the bottom plate guide, an opening communicating with the water guiding pipe is provided at the upper end, and an injection cylinder for horizontally injecting the surface water flowing from the opening is provided in a protruding manner. The oxygen supply device for aquaculture shellfish according to claim 1 or 2, further comprising a body. 5. A raft for cultivating shellfish, which is a method for supplying oxygen mainly to shellfish located in the bottom layer to promote the growth thereof, wherein the raft has a water intake section for taking in surface water at the upper end. Along with fixing the water conduit pipe that reaches the bottom of the shellfish where the lower end portion is located in the bottom layer portion, a water supply propeller is provided at the lower end portion of the water conduit pipe, and the surface water in the water conduit pipe taken from the water intake portion is fixed. Oxygen supply for cultured shellfish, characterized in that a bottom plate guide is provided immediately below the water transfer pipe so that surface water supplied from the water transfer pipe hits and diffuses horizontally. Method. 6. The oxygen for cultured shellfish according to claim 5, wherein the diatom is propagated by introducing the silicic acid solution into the water guiding pipe and sending the silicic acid solution downward together with the surface water. Supply method.