JP2008022813A - Vessel for culturing shellfish and method for culturing shellfish - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vessel for culturing shellfishes, capable of flowing water in a sand layer in the vessel to promote growth of the shellfishes in the sand layer by set near water surface to utilize ebb and flood, and to provide a method for culturing shellfishes by utilizing the vessel for culturing shellfishes. <P>SOLUTION: The vessel for culturing shellfishes comprises a vessel 1 having a water-impermeable side wall part 5 and a water-permeable bottom part 4, and a sand layer 2 for culturing the shellfishes which layer is set in the vessel. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a container and a method for culturing shellfish such as swordfish and clams.

  In the past, shijimi were abundant in brackish waters such as estuaries, and clams were abundant in sand in shallow water, ensuring sufficient catch. However, in recent years, catches of swordfish and clams have decreased due to pollution of rivers, lakes, and shallow waters, and accumulation of sludge. Recently, shijimi has been attracting attention as a health food suitable for preserving liver function, but its catch has been decreasing year by year, and many of them depend on imports from abroad. There is a demand for an effective method for culturing shellfish that live in brackish waters and shallow sands, such as swordfish and clams.

Patent Documents 1 to 3 describe shellfish culture containers and shellfish culture methods. The shellfish containers described in these documents are placed in the sea. Patent Documents 1 and 2 describe providing a sand layer in a container, but do not describe a configuration for flowing seawater in the sand layer. Patent Document 3 describes that a through-hole 7 is provided in the outer peripheral portion of a container to cause seawater in the container to flow, but does not describe provision of a sand layer in the container. In patent document 3, the sand dropping hole 8 is provided in the bottom part of the container, and it is not assumed at all that the sand layer is provided in the container.
JP-A-7-177833 Japanese Patent Laid-Open No. 9-266736 JP-A-6-343370

  A sand layer is necessary for the cultivation of shellfish that like sand, such as swordfish and clams. In order to promote the growth of shellfish in the sand layer, it is necessary to cause the water in the sand layer to flow. However, unless underflow water is generated, the water in the sand layer is not sufficiently flowed.

  The present invention provides a container for shellfish culture that can be installed near the water surface to flow water in the sand layer in the container using tides and the like, and promote the growth of shellfish in the sand layer, and the shellfish An object of the present invention is to provide a shellfish culture method using an aquaculture container.

The present invention has the following configuration in order to solve the above-described problems.
A shellfish cultivation container having a container having a water-impermeable side wall and a water-permeable bottom and a sand layer for shellfish cultivation inside the container.

Moreover, it has the following embodiments.
The water permeable bottom is a porous body.
The water permeable bottom is porous concrete.
It further has water introduction means for introducing fresh water or seawater from the top or bottom of the container to the sand layer.
The shellfish cultivation container is installed in a water surface area, and the water in the sand layer is caused to flow through the water-permeable bottom by tides.

  Since the side wall surrounding the container is impermeable and the bottom is water permeable, and there is a sand layer on the bottom, the flow of water into and out of the container always creates a flow that passes through the bottom and the sand layer. By installing this container near the surface of the brackish water or near the surface of the shallow water, the water in the sand layer can be flowed by allowing water to flow in and out of the container through the bottom due to tides and the like. Shijimi, clams, etc. grow on algae in the sand layer, but the algae nutrients and dissolved oxygen are supplied into the sand layer due to the flow of water in the sand layer due to tides. The growth of is promoted. It also eliminates topographical restrictions on shellfish habitat and enables efficient aquaculture.

  By using porous concrete as the water-permeable bottom, it is possible to prevent the sand from flowing out in the sand layer while maintaining water permeability. Furthermore, the water in the sand layer can be effectively flowed by providing the water guiding means. If a check valve is provided at the upper part of the container side wall as a means of water transfer, water can be effectively flowed from the check valve to the upper part of the sand layer during the high tide level in response to tides. Can make osmotic flow. You may use what utilized the energy of the water level of a relatively high river as a water conveyance means. If a pipe is used as the water guiding means, an osmotic flow can be created in the sand layer with the energy of the water pressure, and if a pump or the like is used, it can be installed in a place where there is almost no fluctuation in the water level around the container.

  A first embodiment of the present invention will be described. FIG. 1 is a schematic diagram of this embodiment. The shellfish cultivation container 1 is installed in the vicinity of the surface of the water area where the tides are full. The shellfish cultivation container 1 includes a water-impermeable side wall portion 5 surrounding the periphery and a water-permeable bottom portion 4. A sand layer 2 is provided in the shell culture container 1, and shellfish 3 such as swordfish and clams are grown in the sand layer 2. The shellfish cultivation container 1 is fixed to the ground 7 by a support 6 so that it does not move due to tidal flow or flow. The water surface around the shell culture container 1 fluctuates between the water surface 9 at high tide and the water surface 10 at low tide due to tides. Osmotic flow in the water-permeable bottom 4 and the sand layer 2 occurs due to fluctuations in the water surface around the shell culture container 1, and the water surface 8 in the container fluctuates.

  The flow of water in the shellfish cultivation container 1 due to tides will be described with reference to FIGS. FIG. 2 is a diagram at high tide. The water level around the shellfish cultivation container 1 rises as it approaches high tide. Since the water in the shell culture container 1 is connected to the water around the container through the water-permeable bottom 4 and the sand layer 2, the water level 8 in the container tends to approach the water level 9 around the container. At this time, water around the container flows into the container from the bottom 4, and the inflowed water penetrates into the sand layer 2. Thereby, nutrients and dissolved oxygen contained in the water around the container are taken into the sand layer 2. The opposite phenomenon occurs during the low tide level. FIG. 3 is a diagram at low tide. The water level around the shellfish cultivation container 1 decreases as it approaches low tide. Since the water level 8 in the container tends to approach the water level 10 around the container, the water in the sand layer 2 flows out of the container through the bottom 4. Thereby, the water in which the dissolved oxygen in the sand layer 2 decreased can be discharged | emitted out of a container.

  FIG. 4 is a schematic diagram of the second embodiment. In the first embodiment, the inflow of water into the container in the time zone with a high tide level is performed through the bottom part 4, but depending on the tide level difference and the water permeability of the sand layer 2, the water around the container is sufficiently sufficient to reach the upper part of the sand layer 2. May not reach. In 2nd Embodiment, this is solved by providing the non-return valve 11 in the upper part of the wall part 5 of the container 1 for shellfish cultivation. The check valve 11 is configured to pass water only from the outside to the inside of the container. When the water level around the container is higher than the water level inside the sand layer, the water around the container flows into the container through the check valve 11. When the water level around the container is lower than the water level inside the container, there is no osmotic flow in the sand layer, but the continuous tidal flow causes intermittent osmotic flow that flows downward in the sand layer, causing the water around the container to flow throughout the sand layer. Can be spread.

  FIG. 5 is a schematic diagram of the third embodiment. In the first embodiment and the second embodiment, it is assumed that the shellfish culture container 1 is installed in a place where there is a tide, but the shellfish culture container 1 has almost no water level fluctuation around the container. There is a possibility to install it in a place that does not exist. The third embodiment is an embodiment in the case of installing in such a place. The water guiding means 12 is provided on the upper part of the shellfish cultivation container 1, and water is introduced from the upper part of the container. The inflowing water flows out of the container through the sand layer 2 and the bottom 4.

  FIG. 6 is a schematic diagram of the fourth embodiment. In the third embodiment, the water guiding means is provided on the upper part of the shellfish cultivation container 1, but in the fourth embodiment, the water guiding means 13 is provided below the bottom portion 4. The water flowing in from the bottom 4 overflows from the upper part of the shellfish cultivation container 1 through the sand layer 2. Although it is conceivable to use a pump or the like as the water guiding means 12, energy of a water level such as a relatively high river may be used.

  As mentioned above, although one example of the embodiment of the present invention has been described based on the drawings, the present invention is not limited to the illustrated example, and various modifications are possible within the scope of the technical idea described in the claims. Needless to say.

1 is a schematic diagram of a first embodiment of the present invention. The figure at the time of high tide of 1st Embodiment of this invention. The figure at the time of low tide of 1st Embodiment of this invention. Schematic of 2nd Embodiment of this invention. Schematic of 3rd Embodiment of this invention. Schematic of 4th Embodiment of this invention.

Explanation of symbols

1 Shellfish container 2 Sand layer 3 Shellfish (swordfish, clams, etc.)
4 Bottom (porous body)
5 Side wall (impermeable)
6 Strut 7 Ground 8 Water surface in container 9 Water surface at high tide 10 Water surface at low tide 11 Check valves 12, 13

Claims (5)

A container having an impermeable sidewall and a permeable bottom;
A shellfish cultivation container having a sand layer for shellfish cultivation inside the container.   The shell for culturing shellfish according to claim 1, wherein the water-permeable bottom is a porous body.   3. The shellfish cultivation container according to claim 2, wherein the water-permeable bottom is porous concrete.   The shellfish cultivation container according to any one of claims 1 to 3, further comprising water guiding means for guiding fresh water or seawater from the top or bottom of the container to the sand layer. 5. A shellfish culture method, wherein the shellfish culture container according to any one of claims 1 to 4 is installed in a water surface area, and water in the sand layer is caused to flow through the water-permeable bottom by tidal flow.

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