JPH09271280A - Seaweed bed forming member and seaweed bed forming method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the colonization rate of a useful seaweed kind by preventing insect damages by seaweed eating animals at the time of forming a seaweed bed. SOLUTION: This seaweed bed forming member 10 is in a structure for which the repellent 14 of the seaweed eating animals is held there between two sheets 12a and 12b composed of decomposing resin and is installed in the sea of a reef or the like for instance. The installed seaweed bed forming member 10 starts to collapse little by little by the action of the decomposing resin and the repellent 14 starts to dissolve little by little in seawater, accompanying it. Then, the seaweed eating animals flee from the reef or the like by the action of the repellent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seaweed bed forming member used for forming a seaweed bed of useful algae and a seaweed bed forming method using the same.

[0002]

2. Description of the Related Art In recent years, a phenomenon called so-called "isoyake" in which lime algae proliferate remarkably frequently has disappeared due to disappearance of seaweed beds composed of useful algae such as kelp and Honda straw.
The disappearance of the seaweed beds and the expansion of the rocky area will not only reduce useful algae but also the number of aquatic animals that live in the seaweed beds, leading to a large loss of marine resources. As a countermeasure against this, the present applicant has proposed a technology for recovering the seaweed bed by installing a vanishing artificial algal reef made of degradable resin in the rocky area (for example, Japanese Patent Application No. 6-208175). ).

[0003]

However, even if the disappearance type artificial algal reef is repeatedly installed, a sufficient effect cannot be obtained if the useful algae are damaged by algae such as sea urchin and abalone.

[0004]

Therefore, an object of the present invention is to provide a seaweed bed forming member and an algae using the seaweed bed forming member, which can improve the fixing rate of useful algae by preventing feeding damage caused by algae in forming the seaweed bed. It is to provide a method of creating a place.

[0005]

The seaweed bed forming member according to the present invention is formed in a sheet form from a degradable resin containing a repellent for algae. In addition to the repellents for algae, useful seaweed fertilizers may be included.

The method for creating a seaweed bed according to the present invention comprises laying the seaweed bed forming member according to the present invention as it is on the seabed, or cutting the seaweed bed forming member according to the present invention into a plurality of cord-like bodies, These ropes are twisted together to form a rope, and the rope is laid on the seabed or in the sea.

The "repellents for algae" include harmful substances, alarm substances, escape behavior inducing substances and the like for algae. The term "useful algae" includes flowering plants such as eelgrass and koala, as well as hidden flowering plants such as wakame, kelp, and straw. “Degradable resin” refers to a resin that decomposes and disappears in a natural environment, and specifically refers to a resin that exhibits biodegradability, water solubility, and the like. Biodegradable resins include microbial production type such as poly (hydroxybutyrate / hydroxyvalerate) copolymer, petroleum synthetic type such as polyethylene succinate, polybutylene succinate and polycaprolactone, plant synthetic type such as poly-L lactic acid. , Starch + polyvinyl alcohol and other natural polymer types, and the like.
Examples of the water-soluble resin include polyvinyl alcohol, cellulosic polymers, paper, and clay.

As repellents for algae, diterpenes,
Triterpenes, terpenes containing 1,4-diacetoxybutadiene moieties, terpenes containing halogens, monoterpenes containing halogens, avrainvilleol, cymopol, tannins, polyphenol fractions with a molecular weight of 3000-30000, tannic acid, free sulfuric acid, stypodiol, taondiol, dictyol E,
Bifurcarenone, halogen compounds, fatty acids containing acetylene, elatol, lanosolsulfate and the like can be mentioned.

It is assumed that useful algal larvae have grown by installing, for example, a vanishing artificial algal reef on a rocky reef in the rocky area. Then, since the alga-eating animals gather, the buds will be damaged by this condition. Therefore, the seaweed bed forming member according to the present invention is installed on this reef or the like. The seaweed bed forming member begins to disintegrate little by little due to the action of the degradable resin, and along with this, the repellent begins to gradually elute into seawater. Then, the alga-eating animals escape from the reef or the like by the action of the repellent. Since the repellent agent continues to elute little by little over a long period of time, its action also continues over a long period of time. Therefore, the larvae grow steadily and become adults, so that the reef or the like having the seaweed bed constructing member becomes the seaweed bed. On the other hand, the seaweed bed building member disappears due to the action of the degradable resin,
It does not interfere with adult growth and does not pollute the natural environment.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a partially cutaway perspective view showing a first embodiment of a seaweed bed formation member according to the present invention. FIG. 2 is a perspective view showing a method for manufacturing the seaweed bed forming member of FIG. 1, and the steps proceed in the order of FIG. 2 [A], FIG. 2 [B], and FIG. 2 [C]. FIG. 3 is a partially cutaway perspective view showing a second embodiment of a seaweed bed formation member according to the present invention. Hereinafter, description will be given with reference to these drawings. However, in FIG. 1 to FIG. 3, the seaweed bed forming member is enlarged in the thickness direction for the sake of convenience of explanation.

The seaweed bed forming member 10 of the first embodiment has a structure in which the repellent 14 for an algae is sandwiched between two sheets 12a, 12b made of degradable resin. The sheets 12a and 12b are manufactured by, for example, extrusion molding using a decomposable resin as a raw material. Sheet 12a, 1
The thickness of 2b is 0.5 mm so that the repellent 14 can be easily eluted.
The thickness is preferably not more than 0.1 mm, and more preferably 0.1 mm or more in order to obtain sufficient strength. Also, sheet 1
The thickness of 2a and 12b may be uniform, but in order to prolong the elution time of the repellent 14, a gradient may be provided so as to change from a thin portion to a thick portion. The repellent agent 14 may be in any form such as granular, powdery or liquid form. The repellent 14 may not be sandwiched between the sheets 12a and 12b, but may be contained in the sheets 12a and 12b themselves at the stage of film formation, for example.

As the degradable resin for the sheets 12a and 12b, starch + modified polyvinyl alcohol (trade name "Matterby": Nippon Synthetic Chemical Co., Ltd.), poly (hydroxybutyrate / hydroxyvalerate) copolymer (trade name "Biopol : Zeneca Co., Ltd., starch-based polymer (trade name "Nobon": Warner-Lambbert), polycaprolactone (trade name "Tone": Nippon Unicar Co., Ltd.), aliphatic polyester (trade name "Bionore": Showataka) Molecule Co., Ltd.), poly-L lactic acid (trade name “Lacty”: Shimadzu Corporation), etc. are commercially available.

The seaweed bed forming member 10 is manufactured as follows. First, the repellent 14 is placed on the sheet 12b (FIG. 2A). Subsequently, the sheet 12a is placed on the repellent 14, and the sheets 12a and 12b are pressed so as to sandwich the repellent 14 and the sheets 12a and 12b are heated (FIG. 2B). As a result, the sheets 12a and 12b are pressure-bonded with the repellent 14 sandwiched therebetween, and the seaweed bed formation member 10 is completed (FIG. 2C). Note that, instead of pressure bonding, adhesion with an adhesive or the like may be used.

The seaweed bed forming member 20 of the second embodiment is composed of three sheets 12a, 12b, 12c made of degradable resin.
Further, it has a structure in which the repellent 14 for algae is sandwiched. As described above, the number of sheets 12a, ... May be any number. By using a structure in which a large number of sheets 12a, ... Are stacked while sandwiching the repellent 14, the elution time of the repellent 14 can be further lengthened.

FIG. 4 is an explanatory view showing the first embodiment of the seaweed bed forming method according to the present invention, and FIGS.
Time progresses in the order of [B] and FIG. 4 [C]. Hereinafter, description will be given with reference to this drawing.

It is assumed that the useful algal larva S ₁ has grown by installing, for example, a disappearing artificial algal reef on the rock reef R in the rocky area. Then, sea urchin U, abalone A, fish F, etc., which are algae, are gathered, so that the bud S ₁
Will be damaged by food. Therefore, the reef R is covered with the seaweed bed creating member 10 (FIG. 4 [A]). At this time, the seaweed bed creating member 10 is fixed to the reef R by a weight, a wedge, or the like (not shown) so that the seaweed bed creating member 10 is not washed by the seawater W. The seaweed bed forming member 10 gradually begins to disintegrate due to the action of the decomposable resin, and along with this, the repellent 14 gradually begins to dissolve into the seawater W. Then, the sea urchin U, the abalone A, the fish F, and the like escape from the reef R by the action of the repellent 14 (FIG. 4).
[B]). Therefore, the sprout S ₁ grows smoothly to become the adult S ₂ , so that the reef R on which the seaweed bed formation member 10 is installed becomes the seaweed bed (FIG. 4C). On the other hand, since the seaweed bed forming member 10 disappears due to the action of the degradable resin, it does not interfere with the growth of the adult S ₂ and does not pollute the natural environment.

The seaweed bed forming member 10 may be provided with a through hole for supplying sunlight or seawater to the bud S ₁ , or may be translucent for supplying sunlight to the bud S ₁ . May be included.

FIG. 5 is a perspective view showing a second embodiment of the seaweed bed forming method according to the present invention.
The process proceeds in the order of [B] and FIG. 5 [C]. Hereinafter, description will be given with reference to this drawing.

First, the seaweed bed forming member 10 is prepared (see FIG. 5).
[A]). Then, the seaweed bed forming member 10 is cut into long and thin pieces to form a plurality of string-shaped bodies 101 to 105 (FIG. 5 [B]). Subsequently, the cord-like bodies 101, ... Are twisted together to form a rope 30 (FIG. 5C). At this time, the rope 30 may be made into a disappearing artificial algal reef by attaching spores or larvae of useful algae to the rope 30. Then, the rope 30 is laid on the seabed or in the sea in the same manner as shown in FIG.

Needless to say, the present invention is not limited to the above embodiment. For example, the seaweed bed forming members 10 and 20 can be used not only for seaweed bed formation but also for aquaculture of useful algae, and can also be used in fresh water such as ponds, rivers, and lakes.

Further, the seaweed bed forming members 10 and 20 may contain aquatic fertilizers such as nitrates, ammonia salts and sulfates. In this case, the growth of useful algae can be promoted.

[0022]

EFFECTS OF THE INVENTION According to the seaweed bed forming member and the seaweed bed forming method according to the present invention, the seaweed bed forming member is gradually collapsed by the action of the degradable resin, and along with this, the repellent of the alga-eating animal is gradually contained in seawater. Since it elutes into, it is possible to eliminate algae for a long period of time. Therefore, it is possible to prevent feeding damage caused by an alga-eating animal when creating a seaweed bed, and thus it is possible to improve the rate of fixing useful algae. Moreover, since the seaweed bed forming member disappears due to the action of the degradable resin, it does not interfere with the growth of adult useful algae and does not pollute the natural environment, and therefore does not need to be recovered. In addition, since useful algae such as sea urchin and abalone can be driven into a certain area, their capture can be facilitated.

When it is used as a sheet, it can be folded and is convenient for storage and transportation, and it can be easily installed only by covering artificial reefs such as reefs and concrete blocks.

When a fertilizer for useful algae is contained in the seaweed bed forming member, the seaweed bed forming member is gradually collapsed by the action of the decomposable resin, and the fertilizer is supplied little by little to the useful algae. It is possible to grow useful algae over a period of time. Therefore, in addition to being able to prevent feeding damage by an alga-eating animal at the time of creating a seaweed bed, it is possible to promote the growth of useful algae, so that the rate of fixing useful algae can be further improved.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing a first embodiment of a seaweed bed formation member according to the present invention.

FIG. 2 is a perspective view showing a method for manufacturing the seaweed bed formation member of FIG. 1, and the process proceeds in the order of FIG. 2 [A], FIG. 2 [B], and FIG. 2 [C].

FIG. 3 is a partially cutaway perspective view showing a second embodiment of a seaweed bed forming member according to the present invention.

FIG. 4 is an explanatory view showing a first embodiment of a seaweed bed formation method according to the present invention, and is FIG. 4A, FIG. 4B, and FIG. 4C.
Time progresses in the order of.

FIG. 5 is a perspective view showing a second embodiment of the seaweed bed creating method according to the present invention, and is FIG. 5A, FIG. 5B, and FIG. 5C.
The process proceeds in the order of.

[Explanation of symbols]

10,20 Seaweed bed formation member 101-105 String-like body 12a, 12b, 12c Sheet 14 Repellent 30 Rope S ₁ Sprout of useful alga S ₂ Adult of useful alga

Claims (4)

[Claims] 1. A seaweed bed constructing member formed in a sheet shape from a degradable resin containing a repellent for an algae. 2. A seaweed bed forming member, which is formed in a sheet shape from a degradable resin containing a repellent for algae and a fertilizer for useful seaweed. 3. A method for creating a seaweed bed, wherein the seaweed bed creating member according to claim 1 or 2 is laid on the seabed. 4. The seaweed bed forming member according to claim 1 or 2 is cut into a plurality of long and thin strings, and the strings are twisted together to form a rope, which is laid on the seabed or in the sea. A method for creating a seaweed bed.