JP2007215449A - Method for raising shellfishes - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for simply and economically raising shellfishes on a small scale at a high growth rate without requiring large-sized equipment. <P>SOLUTION: The method for raising the shellfishes is carried out as follows. Spats or young shellfishes of shellfishes are nipped between narrow nonwoven fabrics containing biodegradable fibers at a prescribed interval, twisted and included therein. The resultant stringy material is continuously embedded in at least one groove in earth and sand at the seabed while digging the groove. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a shellfish growing method, and more particularly, to a method for easily and efficiently growing a shellfish, particularly a juvenile shellfish or a young shellfish, and also relates to a method for simultaneously growing seagrass serving as shellfish food.

In recent years, the sea and lakes have been polluted, and it has become a major problem for the growth of sea-bottomed organisms such as shellfish. At the same time, shellfish have been killed together with seagrass in some places, which has become a major social problem. Improvement measures are desired. Seaweeds play an important role in marine ecosystems because they provide a habitat for various organisms and gather various fish using them as food.

As a method for growing shellfish, there is a conventional method in which juvenile shellfish or young shellfish are sprinkled on the seabed and grown, but the probability of growth is low, and it is not an efficient method. Patent Document 1 discloses a method for culturing and growing juvenile shellfish or juvenile shellfish in a certain connected container and hanging them in the sea. However, cost and labor are clear and economically superior. It's not a method. Patent Document 2 discloses a shell reef using an artificial block, but requires a large-scale construction and cannot be said to be a simple and efficient method.
JP 10-42626 A JP 2002-84903 A

  An object of the present invention is to provide a method for growing shellfish with a high growth rate, which is neatly arranged at a constant density using a simple device without requiring large-scale equipment.

  In view of the conventional problems and the present situation, the present inventor sandwiches shells of juvenile shellfish or young shellfish at a constant interval in a narrow-width non-woven fabric containing a biodegradable fiber having a specific range of water absorption, and twists and encapsulates them. The present inventors have found that the above-mentioned problems can be solved by laying the string-like object in the groove portion of the seabed using the string-like object, and have reached the present invention.

That is, the invention claimed in the present application is as follows.
(1) At least one groove in the bottom of the seabed with a braided or shellfish sandwiched between narrow nonwoven fabrics containing biodegradable fibers at regular intervals and twisted and encased. A method for growing shellfish, characterized by being continuously buried in the groove while digging.
(2) The method according to (1), wherein the narrow-width nonwoven fabric is a cellulose fiber nonwoven fabric.
(3) The method according to (1) or (2), wherein the thin nonwoven fabric has a water absorption ratio of 3 to 15 times and an air permeability of 100 to 1000 cc / cm ² · sec.
(4) The method according to any one of (1) to (3), wherein a cotton yarn and / or a regenerated cellulose fiber yarn is wound around the outside of the string.
(5) The method according to any one of (1) to (4), wherein the string-like object has a strength of 10 to 40N.
(6) The method according to any one of (1) to (5), wherein the narrow nonwoven fabric is impregnated or adhered with a substance that assists the growth of shellfish.
(7) The method according to (6), wherein seaweed seeds are included in the narrow nonwoven fabric.

  According to the present invention, shellfish can be rearranged in a certain density range and can be cultivated with high space productivity without using a large-scale device in rearing shellfish larvae or juveniles on the sea floor. . Further, by supporting a material necessary for the growth of shellfish on a string-like material or encapsulating it, a further favorable growth can be expected. Furthermore, since a biodegradable string is used, it is an environmentally friendly method.

The narrow-width non-woven fabric used in the present invention can be set to a size that can be contained in accordance with the size of the juvenile shellfish or young shellfish, and the width is 10 to 100 mm, preferably 20 to 50 mm. The basis weight is preferably in the range of 10 to 60 g / m ² , more preferably 15 to 40 g / m ² . If the width and basis weight of the narrow non-woven fabric are within this range, the shellfish or larvae of the shellfish are encased at regular intervals to form a string-like material. And an appropriate thickness can be formed.

  The fibers that make up the narrow nonwoven fabric must contain biodegradable fibers. After being laid on the seabed, juveniles or larvae grow in the soil, and the nonwoven fabric biodegrades in the sediment on the seabed. It is necessary to do. The biodegradation rate is preferably biodegradable according to the growth rate of juvenile shellfish or young shellfish in the soil. For example, biodegradation in the sediment of the seabed is possible in 3 to 6 months. preferable.

  Examples of biodegradable fibers include cellulosic fibers such as rayon, cupra, cotton, hemp, and pulp, and thermoplastic fibers such as aliphatic polyester fibers such as polylactic acid. Among these, regenerated cellulose fibers such as rayon and cupra are preferable from the viewpoint of water absorption and biodegradation speed. Regenerated cellulose fibers are excellent in water absorption and biodegradability.

As content rate of the biodegradable fiber in a narrow nonwoven fabric, 30 weight% or more is preferable, More preferably, it is 50 to 100 weight%. If it is less than 30% by weight, the remaining non-biodegradable fibers increase, and the burden on the environment increases.
The fineness of the fibers constituting the nonwoven fabric is preferably 1 to 10 dtex, more preferably 2 to 5 dtex.

  Nonwoven fabric production methods include wet papermaking, short fiber spunlace nonwoven fabric, wet spunbond method, etc., but from the viewpoint of uniformity, economy, and degree of opening as a nonwoven fabric, the wet spunbond method is preferred. As the nonwoven fabric, a cupra long fiber nonwoven fabric manufactured by a wet spunbond method is excellent.

  The nonwoven fabric of the present invention is preferably excellent in water absorption and water retention. The water absorption preferably has a water absorption ratio of 3 to 15 times the own weight, and more preferably 5 to 10 times. If the water absorption is within this range, sufficient water can be obtained for the growth of juvenile or larvae, and the sedimentation in seawater is good, and the adhesion to the ground when absorbed is excellent. It is effective in improving the laying property of the string-like material on the seabed.

  The narrow nonwoven fabric of the present invention is preferably impregnated or adhered with a substance that assists the growth of shellfish at the same time as the juvenile shellfish or the young shellfish. A nutrient source can be enclosed in a microcapsule and sandwiched between web sheets constituting a nonwoven fabric to be fixed. By sandwiching seaweeds and the like in a non-woven fabric, shellfish can be grown using seaweed as food. When microcapsules are used, sustained release properties can be expected, and effects over a long period can be expected.

  The string-like material used in the present invention is formed by cutting a nonwoven fabric into a predetermined width to form a narrow-width tape, sandwiching a juvenile shell or a young shellfish between the tapes, and twisting the seed so as to wrap it with the nonwoven fabric. It is a thing. At that time, it is preferable from the viewpoint of reinforcing the strength that the outer layer portion of the string-like material is wound around the string-like material while alternately intersecting with the cotton yarn or the cellulose fiber yarn. The reinforcing yarn may be wound at the same time when a narrow nonwoven fabric is twisted to form a string. The reinforcing cotton yarn is preferably 10 to 40, and the cellulose fiber is preferably 100 to 200 dtex rayon filament fiber. This string is usually used by being wound on a reel.

  The interval between the juvenile shellfish or the juvenile shellfish can be set as appropriate according to the type, size and degree of growth of the shellfish, and can be included at regular intervals. In the clam juvenile which is a typical shellfish, it is preferable to set at intervals of 3 to 10 cm. As in the present invention, when larvae and the like are wrapped with a narrow nonwoven fabric, the larvae and the like are not dropped at the time of laying, and can be regularly and regularly grown with a constant arrangement density at regular intervals.

In the case where the narrow nonwoven fabric is twisted into a string shape, the number of twists is preferably 5 to 50 times / m. When twisting is strengthened, although it is good in terms of immobilization of juvenile shellfish or juvenile shellfish, growth may be hindered.
The thickness of the string-like material is in the range of 2 to 10 mm, preferably 3 to 5 mm. When encasing juvenile shellfish or the like in a thin nonwoven fabric, it is slightly loosened rather than tightly wound and bulky. It is better to wrap around with sex.
When laying larvae or larvae on the sea floor using the string-like material of the present invention, juveniles and the like can be arranged at regular intervals in the length direction of the string-like material, By arranging the grooves, juvenile shells and the like can be arranged according to the groove interval.

  In the present invention, since a relatively thin string-like object is used, the interval between the multiple lines can be set freely. For example, it can be arranged neatly in a narrow range with high density, or it can be roughly arranged in a wide range. That is, the arrangement density and arrangement configuration can be changed and set from a small scale to a large scale as appropriate in accordance with the topographical condition of the seabed and the growth plan of juvenile shellfish.

  In the present invention, when seaweed or seagrass seeds are encapsulated in a thin non-woven fabric at the same time as the juvenile shellfish or young shellfish, the growth of seaweeds and seaweeds is carried out in a simultaneous progression system along with the growth of shellfish, orderly and orderly Co-growth of shellfish and seaweed becomes possible.

Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 1 is a developed view of a string-like object in which young shellfish and the like used in the present invention are encapsulated in a nonwoven fabric. This string-like material 1 includes a juvenile shell 3 and the like sandwiched between thin non-woven fabrics 2 made of biodegradable fibers, is twisted and enclosed, and further encloses a cotton thread 4 around the shell and the like It is made of reinforced by wrapping them so that they cross each other.

FIG. 2 is an explanatory view schematically showing an apparatus for laying the string-like object on the seabed. This apparatus includes a guide tube 6 for receiving the string-like object 1 wound on a reel 5 placed on a ship, and a feeding means for laying the string-like object 1 on the seabed via the guide tube 6. The laying device 7 provided with the laying device 7, the eaves portion 8 and the feeding portion 9 provided in the laying device 7, and the covering means 10 supported swingably on the upper portion of the laying device 7. The feeding unit is provided in the feeding unit 9 and a known unit such as a pinch roll is used.
The reel 5 is installed in a ship above the sea surface, but may be another place where a string-like object can be supplied stably.

  The guide tube 6 receives the string-like object 1 supplied from the reel 5 in the laying device 7 and serves as a guide for laying the string part in the groove on the sea floor formed by the brim part 8. The laying device 7 has a ridge portion 8 for digging a groove on the seabed at the front thereof, and is configured to advance forward while digging the groove on the seabed by appropriate power means. The hook portion 8 and the feeding portion 9 are arranged immediately after the hook portion 8 so that the string portion 1 is laid in a groove on the sea floor dug by the hook portion 8. . As the covering means, for example, a scraping device 10 that is slidably provided on the laying device main body is provided on the upper portion of the feeding portion 9, and the groove portion after the string-like material is laid is backfilled and flattened.

  The shape of the groove is set according to the thickness of the string-like material, the depth in the soil suitable for growth of juvenile shellfish or juveniles, the topography on the seabed, and the flow state of seawater, but the depth is 2 to 10 cm and the width is 2 A range of -10 cm is preferred. The number of the grooves may be one, but if the number of the grooves is two to four, etc., it is possible to lay many lines in a single operation, and the laying efficiency is greatly improved. In multi-strips of 2 to 4 or the like, it is possible to use a multi-striped supply reel, a hook part, a feeding part, and a covering means for string-like objects.

  Since the string-like object of the present invention is formed by twisting a narrow tape, the juvenile shellfish or the young shellfish is contained in the string-like object and fixed without falling off. Since it is laid in the ditch and is not affected by the flow of seawater, so to speak, juvenile shellfish, etc., have received double protection, which encourages the growth of certain juvenile shellfish or larvae it can. Furthermore, since the groove portions can be finely and freely arranged as described above, orderly shellfish can be grown. In addition, when laying a flat growth sheet, it is easy to receive the influence of the flow of seawater on the entire surface of the sheet, to receive the liquid resistance of seawater, and to be peeled off. The string-like material of the invention has very little liquid resistance as a surface, and even if a part of the string-like material is peeled off by seawater, the entire surface is peeled only by being in the form of a tape or string as a palm. Therefore, there is an advantage that the risk of being washed away is extremely small.

Hereinafter, the present invention will be specifically described with reference to examples. In addition, the measuring method in an Example is as follows.
(1) Breathability: According to the fragile method of JIS-L-1906.
(2) Liquid Absorption Ratio The liquid absorption ratio in the present invention means that the weight of a sample sampled at 10 cm × 10 cm is measured (W1) after standing at 20 ± 2 ° C. and 65 ± 2% RH for 16 hours or more. After immersing the sample in a pad filled with water for 10 minutes, the sample is taken out and allowed to stand until the drop of water drops from the sample. The weight of the sample is measured (W2), and the absorption indicated by (W2−W1) / W1. It means liquid magnification.
(3) Weight per unit The sample was sampled to 1 m × 1 m, and the four corners and the center were measured, and the average value was calculated.
(4) Single yarn decitex: The constituent single yarn was enlarged and calculated as dtex.
(5) Strength The strength as a string was measured by the JIS-L-1906 method.

[Example 1]
A regenerated cellulose continuous long-fiber non-woven fabric (Benlyse SF204, registered trademark, manufactured by Asahi Kasei Fibers Co., Ltd.) having a basis weight of 20 g / m ² and a single yarn decitex of 1.5 dtex is slit into a width of 30 mm to obtain a thin non-woven fabric. The nonwoven fabric had a water absorption ratio of 13 times its own weight and a breathability of 250 cc / cm ² · sec. Wrap clams (1 cm in size) at 5 cm intervals in this narrow nonwoven fabric to form a 5 mm thick string-like material, and use the rayon yarn 250 dtex and the 10th cotton yarn as the outer layer. Winding while alternately intersecting at intervals of 2 cm, a reinforced string-like material was obtained and wound up on a reel with a length of 1000 m. The strength of the reinforced string was 30N.

Using a device like the one shown in Fig. 1, three strips with a depth of 5 cm and a width of 3 cm are dug at the buttock using a device as shown in Fig. 1 and the string is wound from the tube. The formed string-like material was continuously laid, and then immediately covered with earth and sand, covered, and leveled with a pressure roll.
About 3 months after laying, the growth of the larvae was observed, and in both cases, the larvae grew steadily on the bottom of the seabed, and the string was almost biodegraded. Biodegradability.

The developed view of the string-like thing which included the juvenile shellfish or the young shellfish used for this invention in the nonwoven fabric. Explanatory drawing which shows typically the apparatus which lays a string-like object on the seabed.

Explanation of symbols

1: string-like material, 2: narrow nonwoven fabric, 3: juvenile or juvenile, 4: cotton thread, 5: reel, 6: guide tube, 7: laying device, 8: heel part, 9: feeding part, 10: Coating means.

Claims (7)

While digging at least one groove in the seabed sediment, sandwiching the larvae or juveniles of shellfish at a regular interval between narrow non-woven fabrics containing biodegradable fibers and twisting them A shellfish breeding method, wherein the shellfish is continuously embedded in the groove. The method according to claim 1, wherein the narrow nonwoven fabric is a cellulose fiber nonwoven fabric. The method according to claim 1 or 2, wherein the thin nonwoven fabric has a water absorption ratio of 3 to 15 times and an air permeability of 100 to 1000 cc / cm ² · sec. The method according to any one of claims 1 to 3, wherein a cotton thread and / or a regenerated cellulose fiber thread is wound around the outside of the string-like material. The method according to any one of claims 1 to 4, wherein the string-like material has a strength of 10 to 40N. The method according to any one of claims 1 to 5, wherein the narrow nonwoven fabric is impregnated or adhered with a substance that assists the growth of shellfish. The method according to claim 6, wherein seaweed seeds are included in the narrow nonwoven fabric.

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