JP4201194B2 - Non-feeding benthic farming method - Google Patents

Description

The present invention relates to a no-feeding benthic aquaculture method.

As a method of cultivating shrimp in a pond built on land, a high-density aquaculture method is currently generally adopted that feeds pellets of moving substances to grow shrimp and obtains a harvest of about 500 g / m ² every year. . In this method, the water of the pond is circulated along the periphery of the pond, and the sludge composed of shrimp shells and excrement deposited on the bottom of the pond is collected in the center of the pond. The sludge gathered from the bottom is removed.

There are problems with high-density aquaculture methods, such as feeding costs that occupy half the cost of aquaculture and pressure producers, and sludge removed from aquaculture ponds causes environmental problems. On the other hand, in the rough-release aquaculture method in which shrimp are cultivated without feeding by simply putting seawater into and out of the pond, the yield is extremely reduced, and it is difficult to manage aquaculture.
The present invention has been made in view of the above problems, and provides a shrimp culture method with a higher yield compared to a rough-release aquaculture method in which the feed cost is less than that of a high-density aquaculture method and sludge accumulation is suppressed. The purpose is to do.
Further, the present invention has a large yield compared to the rough-release aquaculture method in which benthic organisms including organisms other than shrimp such as shellfish, giant clam, sea cucumber, and sea bream have a low food cost and sludge accumulation is suppressed. The purpose is to provide a breeding method.

In order to solve the above-mentioned problem, in the present invention, a device for continuously pumping the bottom layer water of the aquaculture pond and diffusing it into the upper layer water of the aquaculture pond is installed in the benthic aquaculture pond, Mix with water, grow aerobic bacteria in the upper water with high dissolved oxygen concentration, decompose organic matter derived from the pond bottom to produce inorganic nutrients, increase the concentration of inorganic nutrients in the upper water, and actively activate photosynthesis And providing a no-feeding benthic culture method characterized by growing phytoplankton.
By bottom water diffuses continuously into the upper water exuviae benthos floating in the bottom layer water, organic matter such as the discharged matter from diffusing into the upper water. Aerobic bacteria grow in upper water with high dissolved oxygen concentration, decompose organic matter derived from the pond bottom, and produce inorganic nutrients. As the concentration of inorganic nutrients in the upper water increases, photosynthesis is activated, phytoplankton grows, and zooplankton that feeds on phytoplankton grows. The benthic organism grows and proliferates supported by abundant phytoplankton and zooplankton that feed.
According to the present invention, benthic organisms can be cultivated without feeding, so the feeding cost is zero. Since the accumulation of sludge on the bottom of the pond can be suppressed, it is possible to use the benthic aquaculture pond continuously for many years. Although the yield is reduced compared to the high-density aquaculture method, it is possible to obtain a larger yield than the rough-culture method. Since phytoplankton and zooplankton that are fed by natural benthic organisms are used as feed, healthy and tasty benthic organisms can be produced.

In a preferred embodiment of the present invention, organic matter is fertilized to the bottom of the benthic aquaculture pond before the start of the aquaculture, and nutrients are replenished at the beginning of the benthic aquaculture.
At the beginning of aquaculture, the organic matter concentration in the bottom water is low. If organic matter such as chicken manure is fertilized at the bottom of the benthic aquaculture pond before the start of aquaculture, phytoplankton and zooplankton can be proliferated by increasing the concentration of inorganic nutrients in the upper layer water even at the beginning of aquaculture. it can. Usually, fertilization only needs to be performed once before the start of aquaculture, so the cost increase due to fertilization is minimal.
In a preferred embodiment of the present invention, organic matter is applied to the bottom of the benthic aquaculture pond during the cultivation.
If the growth of phytoplankton and zooplankton is insufficient, organic matter may be applied to the bottom of the benthic aquaculture pond during cultivation.

In the preferable aspect of this invention, seawater exchange with an open sea is continuously performed with a water exchange pump, and the water temperature and water quality of a benthic organism pond are maintained in a suitable state.
By continuously exchanging seawater with the open sea using the water exchange pump, it is possible to prevent the water quality of the culture pond from deteriorating over time and to prevent the water temperature of the culture pond from rising over time.

In a preferred embodiment of the present invention, the bottom water pool is formed by digging down the bottom of the pond below the apparatus for continuously pumping the bottom water and diffusing it into the upper layer.
Organic matter near the bottom of the pond can be collected in the bottom reservoir and pumped up effectively.

According to the present invention, benthic organisms can be cultivated without feeding, so the feeding cost is zero. Since the accumulation of sludge on the bottom of the pond can be suppressed, it is possible to use the benthic aquaculture pond continuously for many years. Although the yield is reduced compared to the high-density aquaculture method, it is possible to obtain a larger yield than the rough-culture method. Since phytoplankton and zooplankton that are fed by natural benthic organisms are used as feed, healthy and tasty benthic organisms can be produced.

An embodiment in which the present invention is used for non-feeding culture of shrimp which is a kind of benthic organism will be described.

As shown in FIG. 1, a density flow diffusion device 2 is installed at the center of a shrimp culture pond 1 formed along a coastline L. A water intake intake pipe 4 extending from a water exchange pump 3 installed on the sea floor near the coastline L reaches the shrimp culture pond 1 across the bank of the coast. A replacement water discharge pipe 5 that is separated from the replacement water intake pipe 4 and extends from the shrimp culture pond 1 penetrates the coastal bank and reaches the vicinity of the coastline L while having a slight downward slope.

As shown in FIG. 2, the density flow diffusion device 2 includes a floating structure 21 that is submerged in water. The floating structure 21 has an upper section 21a, a middle section 21b, and a lower section 21c.
The bottom water intake pipe 22 extends vertically downward through the center of the lower section 21c in plan view. The upper end of the bottom water intake pipe 22 communicates with the middle section 21 b and the lower end is in the vicinity of the bottom surface of the shrimp culture pond 1. A pump 23 is disposed at a portion extending in the lower section 21 c of the bottom layer water intake pipe 22.
An upper water intake pipe 24 penetrates the center of the upper section 21a in plan view and extends vertically upward beyond the water surface WL of the shrimp culture pond 1. The upper end of the upper water intake pipe 24 is closed. A plurality of water intakes 24a are formed below the water surface of the upper water intake pipe 24 and in a region close to the water surface. The lower end of the upper water intake pipe 24 communicates with the middle section 21b. A pump 25 is disposed at a portion extending in the upper section 21 a of the upper water intake pipe 24.
A plurality of water discharge passages 26 extend horizontally and radially from the peripheral wall of the middle section 21b at intervals in the circumferential direction. The water discharge channel 26 is positioned in the upper layer lower part of the seawater of the shrimp culture pond 1.
The density flow diffusion device 2 floats in the seawater of the shrimp culture pond 1 and is moored at the center of the shrimp culture pond 1 by a mooring line 27 having an anchor.
Cables (not shown) for supplying power to the pumps 23 and 25 extend to a power source disposed in the vicinity of the shrimp culture pond 1.

The no-feeding shrimp culture method according to the present embodiment is performed as follows using the above-described apparatus.
The pump 23 of the density flow diffusion device 2 is operated to continuously pump up the bottom water of the shrimp culture pond 1 through the bottom water intake pipe 22 and discharge it to the middle section 21 b of the floating structure 21. The pump 25 is operated to continuously suck up the upper layer water of the shrimp culture pond 1 through the upper layer water intake pipe 24 and discharge it into the middle section 21 b of the floating structure 21.
The bottom layer water and the upper layer water are stirred and mixed in the middle section 21b. The mixed water is discharged into the upper lower part of the seawater of the shrimp culture pond 1 at the same temperature as the mixed water through the water discharge channel 26. The mixed water enters the layer having the same density as the self in the upper layer stratified according to the density, and diffuses horizontally far away while forming a density flow that is a flow of seawater of the same density.
As the bottom layer water continuously diffuses into the upper layer, organic substances such as shrimp shells and excrement floating in the bottom layer water diffuse into the upper layer water. Aerobic bacteria grow in upper water with high dissolved oxygen concentration, decompose organic matter derived from the pond bottom, and produce inorganic nutrients. As the concentration of inorganic nutrients in the upper water increases, photosynthesis is activated, phytoplankton grows, and zooplankton that feeds on phytoplankton grows. Shrimp grow and proliferate, supported by abundant phytoplankton and zooplankton. The organic matter in the bottom water is transported to the upper layer and decomposed, so that sludge accumulation on the pond bottom is suppressed.
According to the present embodiment, shrimp can be cultivated without feeding, so the feeding cost is zero. Since sludge accumulation at the bottom of the pond can be suppressed, the shrimp culture pond 1 can be continuously used for many years. Although the yield is reduced compared to the high-density aquaculture method, it is possible to obtain a larger yield than the rough-culture method. Because it uses phytoplankton and zooplankton as food for natural shrimp, it can produce healthy and delicious shrimp.

Prior to the start of cultivation, organic matter such as chicken manure is fertilized at the bottom of the shrimp culture pond 1 to replenish nutrient salts at the beginning of shrimp culture.
At the beginning of aquaculture, the amount of shrimp shells, excrement, etc. floating in the bottom water is small, so the organic matter concentration in the bottom water is low. If organic matter is fertilized at the bottom of shrimp culture pond before the start of aquaculture, the organic matter concentration in the bottom layer water is increased even at the beginning of the aquaculture, and the concentration of inorganic nutrients in the upper layer water is increased, so that phytoplankton and zooplankton grow. Can be made. Usually, fertilization only needs to be performed once before the start of aquaculture, so the cost increase due to fertilization is minimal.
If the growth of phytoplankton and zooplankton is insufficient, organic matter may be applied to the bottom of the shrimp culture pond 1 during cultivation.

The water exchange pump 3 is operated, and the seawater from the open sea is continuously supplied to the shrimp culture pond 1 through the water intake pipe 4 for water exchange. The surface water of the shrimp culture pond 1 is naturally released continuously to the open sea through the water discharge pipe 5 for water replacement.
By continuously performing seawater exchange with the open sea, it is possible to prevent the water quality in the shrimp culture pond 1 from deteriorating over time and to prevent the water temperature in the shrimp culture pond 1 from increasing over time. it can.

Instead of continuously exchanging seawater in shrimp culture pond 1 with seawater in the open sea, the seawater in shrimp culture pond is regularly exchanged with seawater in the open sea by opening and closing the sluice in synchronization with seawater tidal. May be.
As shown by a one-dot chain line in FIG. 1, the bottom water pool 6 may be formed by digging the pond bottom below the density flow diffusion device 2. Organic matter near the bottom of the pond can be collected in the bottom reservoir 6 and pumped up effectively. If fertilization before the start of the cultivation is performed in the bottom water reservoir 6, the fertilized organic matter can be effectively diffused into the upper water.

The present invention may be used for aquaculture of benthic organisms other than shrimp such as shellfish, giant clam, sea cucumber, and sea bream. It is possible to realize a large yield compared to the rough-release aquaculture method while suppressing the accumulation of sludge while suppressing the feed cost.

The present invention can be widely used for aquaculture of benthic organisms such as shrimp, shellfish, giant clam, sea cucumber and sea bream.

It is a block diagram of the apparatus for enforcing the no-feeding shrimp culture method based on the Example of this invention. (A) is a top view, (b) is sectional drawing. It is sectional drawing of the density flow spreading | diffusion apparatus for enforcing the no-feeding shrimp culture method based on the Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Shrimp culture pond 2 Density flow diffusion apparatus 3 Pump for water conversion 4 Water intake pipe for water replacement 5 Water discharge pipe 6 Bottom water reservoir

Claims (5)

A device that continuously pumps the bottom water of the aquaculture pond and diffuses it into the upper water of the aquaculture pond in the benthic aquaculture pond, mixes organic matter in the bottom water with the upper water, and has a high dissolved oxygen concentration. The aerobic bacteria are grown on the pond, organic matter derived from the bottom of the pond is decomposed to produce inorganic nutrients, the concentration of inorganic nutrients in the upper water is increased, photosynthesis is activated, and phytoplankton is grown. Feeding benthic farming method. 2. The non-feeding benthic aquaculture method according to claim 1, wherein an organic substance is fertilized on the bottom of the aquaculture pond before the start of the aquaculture, and nutrient salt is replenished at the beginning of the benthic aquaculture. 3. The non-feeding benthic aquaculture method according to claim 1 or 2, wherein organic matter is applied to the bottom of the pond during the cultivation. The non-throwing according to any one of claims 1 to 3, wherein the water temperature and the water quality of the benthic aquaculture pond are maintained in a suitable state by continuously performing seawater exchange with the open sea by a water exchange pump. Feeding organism culture method. The non-feeding benthic organism according to any one of claims 1 to 4, wherein a bottom water reservoir is formed by digging down a pond bottom below a device for continuously pumping bottom water and diffusing it into the upper layer. Farming method.

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