JPH0238173B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] This invention relates to artificial floating algae, and more specifically to artificial floating algae that can hide hatched larvae, seeds, young fish, etc. and migrate from the hatching area to the coastal area. [Prior art] Fish such as tuna, yellowtail, eel, shrimp, and crab that live in the coastal waters of the Japanese archipelago hatch in large numbers, for example in the waters near the Nansei Islands, and produce young fish such as larvae, fry, and young fish. They mainly migrate on ocean currents using floating algae such as sargassum as cover, and reach the waters near the Japanese archipelago or the coasts of other continents, where they become adults. However, floating algae such as sargassum is lighter than seawater that has been torn apart by waves, and the amount of floating algae is only enough to move a small portion of the young fish, and most of the young fish live in coastal waters where they are suitable for growing. The current situation is that they die without reaching this point.
Therefore, if there is a larger amount of floating algae or something that functions as floating algae, it will be possible to dramatically increase near-sea fishery resources. In the past, there have been almost no attempts to artificially create something with functions similar to floating algae.
For example, structures made of synthetic resin that float on seawater,
Alternatively, a bundle of thin film-like or fibrous materials made of polyethylene, polypropylene, etc. can be considered. [Problems to be Solved by the Invention] However, synthetic resins are difficult to decompose and disappear, and they float in the ocean forever, polluting the ocean, and structures become obstacles to ship navigation, so they have not been put to practical use. In addition, floating seaweed such as straw has air bubbles distributed almost uniformly throughout its body, and in the sea it moves as a mass while rotating.
Therefore, the effects of preventing small fish from being predated by large fish and making them easier to hide are not necessarily sufficient, and the size and shape of small fish are not constant, making it difficult to expect a stable effect on attracting fish. This invention was made in view of the above circumstances. The purpose of this product is to allow the growth of young fish and other fish while moving them to coastal waters, thereby increasing nearshore fishery resources.At the same time, compared to synthetic resin products, they decompose and disappear in a short period of time, causing no marine pollution or hindrance to ship navigation. We are proposing artificial floating algae. [Means for solving the problem] This artificial floating algae consists of a floating part with a specific gravity of less than 1 and a hanging part of a fibrous or film-like material with a specific gravity of more than 1. It floats on the sea and follows the ocean currents. It is an artificial floating algae that moves, and the hanging part is made up of multiple rocking pieces that hang down from a floating body floating on the sea for a length of several cm to 4 meters and swing in response to the movement of seawater. It forms a space in which fish can hide, and the main parts of both the floating part and the hanging part are made of easily disintegrating cellulose material. Multiple rocking pieces that swing in response to the movement of seawater hang down from the hanging part of this artificial floating algae, and the space formed between them provides suitable environmental conditions as a hideout for young fry, allowing them to grow at a high density. It can be made to collect at a high level. In addition, this floating algae consists of a floating part of cellulose material and a hanging part of cellulose material, so if it is left in seawater, it will decompose and disappear over several months due to the action of seawater, light, air, bacteria, etc., or the floating part will disappear. They absorb water and sink without losing their buoyancy, and after sinking they decompose and disappear, so by appropriately setting materials and specifications, they disappear after a predetermined migration period and do not cause ocean pollution. Furthermore, by appropriately setting the extinction period, it is possible to separate young fish from drifting algae and establish them in the targeted coastal waters. Cellulose materials also have the advantage of being rich in bacteria and food for plankton and other young fish. The main part of this artificial floating algae is made of easily disintegrating cellulose material, and when it is released into the sea, it decomposes and disappears after a period of several months, and after sinking, it does not stop forming, so-called easily disintegrating material. Must-have. In this invention, the cellulose material refers to a plant material mainly composed of wood fibers (cellulose) such as wood, cork, and rush, a cellulose fiber material such as wood fiber, hemp, and pulp, or a cellulose material such as cellophane,
These are film-like substances made of regenerated cellulose such as flat threads, and any of them can be used under conditions that satisfy the above-mentioned easy disintegration property by appropriately setting design conditions. The hanging part of this artificial floating algae is selected from natural cellulose materials such as cotton, hemp, pulp, etc., and regenerated cellulose materials such as rayon, which have a specific gravity of more than 1 and sink in seawater. These substances are used in the form of fibrous materials, such as long fibers, short fibers, bristles, spun yarns, twisted yarns, cords, knitted fabrics, non-woven fabrics, etc., or in the form of films. And a few cm from the floating body part
4m, preferably 10cm to 3m long, curtain-shaped,
It is hung in the form of tufts, curtains, or blinds to form rocking pieces. When regenerated cellulose flat threads, preferably those with flatness of 20 or more, more preferably 100 or more, are used as the rocking pieces, the wide rocking pieces swing smoothly, and the space between the rocking pieces allows suitable hiding of young and fry. , which works well to prevent small fish from being predated by large fish. It should be noted that a flat thread-like rocking piece has a larger surface area and is more preferable than a round rod-like rocking piece in achieving the object of the present invention. Furthermore, the regenerated cellulose flat yarn has excellent decomposition properties in seawater as described in (Example 5), and is particularly suitable in this respect as well. Compared to natural cellulose materials, regenerated cellulose materials can be easily formed into desired shapes and dimensions, absorb water well, swell, and rock like seaweed in the sea.
It is easy to control the period during which bacteria decomposes and disappears by setting the specifications, and it has many advantages, such as being dyed with a pigment and focusing on a color (brown) suitable for low cost and durability, and is the most excellent. The material is The floating body is made of thin wood, cork, rush, or other cellulose material that is easily photodegradable, or foamed or hollow regenerated cellulose material that floats in the sea and has a specific gravity of 1 to support the weight of the hanging part. It is selected from the following materials and is used in plate, rod, frame, or spherical shapes. In order for artificial floating algae to float in seawater, the floating body must have buoyancy. However, it is not necessary to make the buoyancy of the floating body part unnecessarily large. The period of migratory movement of this artificial floating algae may be predicted, and the materials and specifications may be set so that after floating for that period, it gradually absorbs water and sinks without losing its buoyancy, or it decomposes and disappears.
The length or width of the floating body portion is preferably from about 20 to 30 cm to 2 to 3 m, and the thickness is preferably from several mm to several tens of mm. Embodiments of the artificial floating algae according to the present invention will be described below with reference to the drawings. [Example 1] In Fig. 1, recycled cellulose flat yarn 1 colored brown with a flatness of 2000 and a weave of 4000 denier and a length of 30 cm is folded to form a rocking piece, and a square piece of wood with a side of 20 cm and a thickness of 5 mm is made. Board 2 is used as a floating part, and wood board 2
An artificial floating algae was constructed by fixing flat threads 1 in the shape of a rope at a density of 1 thread per 1 cm ² to one front of the wall to form a hanging part. This artificial floating algae submerges its hanging part in the sea and floats, moving along with the ocean current, and the swinging piece made of flat threads 1 hanging down like a curtain swings according to the movement of the seawater.
The young fish are attracted by the color of the main body, the rocking sound, the rocking whirlpool, the shadow, etc., and gather, and get into the space between the flat threads.
It moved along the ocean currents along with artificial floating algae. Also,
During the migration, a part of the flat thread 1 was torn off by the waves, but it sank, and after about 6 months, the floating part 2 absorbed water, lost its buoyancy, and the entire floating algae sank, causing no marine pollution. [Example 2] In Fig. 2, a jute triplet twisted yarn 3 is used as a swinging piece, a rush round stick 4 with a diameter of 3 cm and a length of 1 m made by bundling rushes is used as a floating body, and a length of 50 cm is attached to the round stick 4. The artificial floating algae was constructed by fixing the jute twisted threads 3 in tufts at 4 cm intervals to create a hanging part. This artificial floating algae also floated by hanging the jute yarn 3 in the sea in tufts, and exhibited the same effects as the floating algae (Example 1). [Example 3] In Fig. 3, swinging pieces made of viscose rayon fabric 5 with a length of 2 m and a width of 30 cm are arranged in four rows in parallel in a curtain shape on a floating body made of a square wooden frame 6 with a side of 30 cm. We created an artificial floating algae by fixing it and creating a hanging part. [Example 4] A rocking piece made of regenerated cellulose film 7 with a length of 1 m and a width of 10 cm was suspended like a curtain on a floating part of a perforated wooden board 8 having a square shape of 1 m on a side and having a large number of through holes. An artificial floating algae was created by creating a hanging part. [Example 5] Regenerated cellulose flat yarn (fiber 12000 denier width
A 75 mm, beige colored dyed yarn) was floated and immersed in seawater with an average temperature of 21°C, and the relationship between the elapsed number of days and strength and elongation was determined. The results were as shown in the table below.

〔Effect of the invention〕

This invention is as described above, and this artificial floating algae is suitable as a shelter for young fish, forms an environment rich in food such as plankton, and efficiently moves young fish that gather in this environment to coastal waters. be able to. Furthermore, even if a large number of artificial floating algae are released to move a large number of young fish, the artificial floating algae will not pollute the ocean or interfere with ship navigation.

[Brief explanation of drawings]

FIG. 1, FIG. 2, FIG. 3, and FIG. 4 are perspective views of artificial floating algae (Examples 1, 2, 3, and 4), respectively. 1... flat thread, 2... wood board, 3... jute twisted yarn, 4... round rush bar, 5... rayon fabric, 6...
...Wooden frame, 7...Striped film, 8...Perforated wooden board.

Claims (1)

[Claims] 1 An artificial floating algae that floats on the sea and moves according to ocean currents, consisting of a floating part with a specific gravity of less than 1 and a hanging part of a fibrous or film-like material with a specific gravity of more than 1. The floating body consists of a plurality of rocking pieces that hang down from the floating body part by a length of several cm to 4 cm and swing in response to the movement of seawater, and a space is formed between the rocking pieces in which fish can hide. This artificial floating algae is characterized in that both the drooping part and the drooping part are made of easily disintegrating cellulose material.