JP4215737B2 - Amamo field construction method - Google Patents

Description

The present invention relates to a method for constructing an eelgrass field using an eelgrass transplantation base sheet in which roots and seedlings of eelgrass, which are a kind of seaweed, are easily established.

  Amamo field plays a very important role not only as a spawning ground for fish and as a growth place for juvenile fish, but also for purifying the sea area due to the absorption of nitrogen and phosphorus, which cause oxygen generation and seawater eutrophication. However, natural eelgrasses have been decreasing due to land reclamation and water pollution. In response to this, various technological developments for restoring the eelgrass field have been promoted.

As a method for transplanting eelgrass, a method is known in which the following several types of base sheets are used and laid on the seabed for transplantation.
(1) A seeding base formed by filling a growth base material together with a eel seed into a bag formed of a material woven with early corrosive fibers and hardly corrosive fibers (Patent Document 1).
(2) A seeding sheet produced by adhering eelgrass seeds to a biodegradable sheet (Patent Document 2).
(3) A seed sheet in which seeds are bonded to a net-like material or sheet-like material made of a biodegradable resin (Patent Document 3).

  In addition to the base sheet, transplanting can be carried out by enclosing the collected larvae with clay lumps, transplanting using pots or concrete blocks, etc. The “planting method” in which the seedlings are transplanted and the “seeding method” in which the collected seeds of the eel are spread on the seabed are known.

JP-A-6-205620 JP 10-42626 A JP-A-11-308904

  In the above-described method for transplanting an ammo using a conventional base sheet, the base sheet is easily damaged or moved in the sea. Therefore, roots and seedlings of eelgrass are difficult to settle, and there is a problem that eelgrass colonization rate is lower than that of the planting and sowing methods.

The present invention has been made in view of the above, and an object thereof is to provide a reclamation method for at least the next one A Mamo field.
(1) To improve the establishment rate of sea cucumber when transplanting sea eel using a base sheet.
(2) Even if there is a wave or flow, transplant and prevent movement and breakage of the base sheet.

  In order to achieve the above object, the present invention combines an internal structure with a material in which the roots and stems of sea cucumber are easily fixed, and transplants the sea bream with an appropriate weight provided with a weight so as not to be affected by waves and currents in the sea. A base sheet for transplantation was installed in a natural amamo field, and an ammo field was established by moving the ammo transplant base sheet, which had established an ammo with a high retention rate, to the sea floor. It is to be created.

A first invention of the present application is an ammo transplant base sheet that germinates and settles sea eels, including a transplant mat, a biodegradable reinforcing net that covers the surface of the transplant mat, and provides unevenness, and the raw A construction method for an ammo field using an ammo transplant base sheet, comprising: a weight attached to a degradable reinforcement net; and an amamo fixed with a biodegradable reinforcement net and a graft mat entangled with roots. The base sheet for transplanting eelgrass is installed in a natural eelgrass field, and eel seeds fall and naturally germinate in the natural eelgrass field, so that the root of the eel is entangled with the biodegradable reinforcing net or the mat for transplantation. Then, a construction method for the eelgrass field is provided, in which the eelgrass transplantation base sheet with the eelgrass settled is transferred to the seabed of the transfer destination .

The second invention of the present application is to provide a method for building an ammo field according to the first invention, wherein the transplantation mat is biodegradable and comprises plant fibers having voids inside.

A third invention of the present application provides a method for forming an ammo field according to the first or second invention, wherein the weight body is a flexible member.

The present invention can obtain at least one of the following effects.
(1) Covering the surface of the base sheet for transplanting eelgrass with a biodegradable reinforcing net and providing unevenness on the surface improved the retention of seeds and sand mud until the seeds of root eels rooted. . Therefore, it is possible to remarkably improve the establishment rate of sea cucumber in the sea cucumber transplantation method using the base sheet.
(2) Since a weight was attached to the bed sheet for transplanting the sea lions to give enough weight to oppose the waves and the flow, the movement of the bed sheet for transplanting the sea am It is possible to transplant the sea bream while preventing damage.
(3) When the mat for transplantation is formed of plant fibers having many internal voids, it has good affinity with the roots of sea cucumber and can be fixed to the mat for transplantation reliably. In particular, the roots of eelgrass seedlings pass through the mat made of plant fibers and are easily embedded in the seabed.
(4) In the natural eelgrass field, the number of eelgrass per unit area, which is the core of growth on the seabed of the relocation site, is large by using the eelgrass transplant base sheet that has been cultivated in a state of high anchorage in advance. , The success rate of the construction of the Amamo field is improved compared with the conventional one.

  Embodiments of the present invention will be described below with reference to the drawings.

(1) Configuration of the Amamo Transplant Base Sheet FIG. 1 shows an example of the amamo transplant base sheet 10.
The amamo transplant base sheet 10 includes a transplant mat 20, a mesh-like biodegradable reinforcement net 30 covering one side or both sides of the transplant mat 20, and a weight body 40 attached to the surface of the biodegradable reinforcement net 30. It consists of.
There are no particular limitations on the dimensions and planar shape of the amamo transplant base sheet 10, and it is appropriately selected according to the place of use.

[Portable mat]
The transplanting mat 20 has a large number of voids inside and is made of a biodegradable material that is corroded and reduced after the transplantation of sea cucumber is completed. For example, plant fibers such as palm fiber and jute can be used.
The thickness of the transplantation mat 20 is such a thickness that does not hinder the roots of the eels from penetrating through the mat and being settled on the sandy mud on the seabed, and is preferably in the range of 2 mm to 20 mm.
The thinner the transplant mat 20 is, the better the penetration of the roots will be. However, the extremely thin one will need to be thick enough to withstand about one year of corrosion because the mat will grow rapidly when the mat is placed on the seabed for a long period of time. It is.
By having a large number of voids inside the transplant mat 20, it is easy to hold sea cucumber seeds and sand mud as a growth base layer, and also has an effect of suppressing the outflow of these held seeds and sand mud.

[Biodegradable reinforcement net]
The biodegradable reinforcing net 30 is a mesh body made of a biodegradable material, and is excellent in durability as compared with the transplant mat 20 and has a long period until the decomposition is completed.
As a material of the biodegradable reinforcing net 30, known compounds such as cellulose acetate, aliphatic polyester, aliphatic polyester amide, aliphatic / aromatic polyester, polyvinyl alcohol, aliphatic polyamide, polyoxyalkylene, and the like are used. it can. The biodegradable reinforcing net 30 may be made of various natural fibers (animal fibers, etc.) and artificial fibers (synthetic fibers, semi-synthetic fibers, regenerated fibers, inorganic fibers, etc.).

  The opening shape of the biodegradable reinforcing net 30 is a square mesh shape, and the opening size is desirably 10 cm to 50 cm. The size of the opening of the biodegradable reinforcing net 30 is larger than the range that does not inhibit the growth of sea cucumber roots, and smaller than the range in which the net 30 can hold the mat 20. Select as appropriate.

  The reason for covering with the biodegradable reinforcing net 30 is that it is easy to retain seeds and sand mud during the period until the seeds are rooted by unevenness on the surface of the transplanting mat 20 and to improve the fixation rate of the eel. This is to reinforce with the biodegradable reinforcing net 30 when the transplantation mat 20 is damaged or corroded.

[Weight body 40]
Because it receives waves and currents in the sea, it is difficult to obtain the stability of the entire base sheet.
Therefore, a weight body 40 having a weight sufficient to ensure stability in water is attached to the surface of the biodegradable reinforcement net 30 over the entire base sheet.
In this example, although the case where the weight body 40 is a chain is shown, a wire rope or the like can also be adopted. In short, it is preferable to have a weight necessary for stability and to have a degree of freedom of deformation (flexibility) that does not hinder the flexibility of the base sheet so that it can follow the undulations of the sea floor.
This flexibility includes both elements based on the connection structure of the weights 40 and elements based on the physical properties of the material itself.
When the weight body 40 is attached in the form of a filament, a concave groove, that is, a valley portion can be formed between the surface of the biodegradable reinforcing net 30 and the weight body 40, and the stem of the eel is hidden behind the weight body 40. It can be grown like a groove. Moreover, the weight body 40 becomes a mountain part, and the force of the wave and the flow that directly act on the stem of the eel is reduced, thereby preventing the eel outflow more effectively until the eel seed is rooted. It will be possible.

  In addition to the arrangement of the weights 40 having a continuity such as a lattice shape or a strip shape, the weights 40 may be partially dotted.

(2) Amamo Field Construction Method Next, an ammo field creation method using the above-described amamo transplant base sheet 10 will be described with reference to FIGS.

[Amamo pre-fixation]
As shown in FIG. 2, the base sheet 10 for sea eel transplantation is first installed on the seabed near the natural sea bream field 50. In installation, a corner-shaped fixing pin 11 is driven in, for example, so that the base sheet 10 for transplanting ammo is not easily peeled off.
In the natural eelgrass field 50, a part of the plant body turns into a flower branch and releases seeds in early spring, but eelgrass seeds 51 are planted on the upper surface of the eelgrass transplantation base sheet 10 as well as the surrounding seabed. Since the eelgrass transplant base sheet 10 is installed including during the seed release period, the number of seeds per unit area of the eelgrass seeds 51 increases as they naturally fall at a relatively high density.
The sea cucumber seeds 51 that have fallen on the surface of the base sheet 10 for transplanting sea cucumber are restrained from free movement due to the flow of waves by the degradable reinforcing net 30 covering the surface and the uneven surface of the weight body 40, thereby suppressing the outflow of sea cucumber seeds 51 Is done.

When the seedling 51 reaches the germination stage, the roots and stems are fixed by being entangled with the biodegradable reinforcing net 30 and the mat 20 for transplantation.
This fixing process will be described in detail. The root hairs grown from the sea cucumber seeds 51 are fixed by entering into the internal spaces of the knitting yarn and the transplant mat 20 constituting the biodegradable reinforcing net 30 and growing while entangled. .

[Transplantation of eelgrass]
The eelgrass transplanted seedling 10 is removed and transported to the seafloor of the transfer destination and laid in close contact with the seafloor to complete the transplantation.
A known method such as fixing with the fixing pin 11 or the anchor described above can be applied as a method for fixing the ammo transplant base sheet 10.
Since the flexibility of the ammo transplant base sheet 10 itself does not change even after the eelgrass has settled, the flexibility of the amamo transplant base sheet 10 can be used to smoothly move the base sheet 10 and Since the roots are tightly entangled and integrated with the inside of the ammo transplant base sheet 10, it is difficult for the sea eels to flow out of the amamo transplant base sheet 10 during the transfer operation.

Further, as shown in FIG. 3, after transplanting, the sand mud 54 and the sea eel can be kept satisfactorily due to the irregularities on the surface of the sea bream transplant base sheet 10 and the presence of the internal gaps in the transplant mat 20. .
The sea bream 52 continues to grow with the passage of time, and the root 53 penetrates the transplant mat 20 of the sea bream transplant base sheet 10 and the biodegradable reinforcing net 30 on the back surface to firmly root the seabed ground.
The transplanted Amamo 52 group becomes the nucleus, and the rhizome grows to form a new strain (nutrient strain). From then on, the release of seeds to the surrounding seabed and germination are repeated in order to create a natural eelgrass field.
In the growth process of the eelgrass group, the mat 20 for transplantation of the base sheet 10 for eelgrass is first decomposed, then the biodegradable reinforcing net 30 is decomposed, and finally the weight body 40 is decomposed due to corrosion and disappears. To do.

The perspective view which shows an example of the base sheet for sea cucumber transplantation concerning this invention Explanatory diagram of how to build amamo Cross-sectional view of the base sheet for transplanting sea eel after transplanting

Explanation of symbols

10 ... Amamo transplant base sheet 11 ... Fixing pin 20 ... Transplant mat 30 ... Biodegradable reinforcement net 40 ... Weight body 50 ...・ ・ ・ Natural eelgrass ground 51 eelgrass seeds 52 eelgrass 53 eelgrass roots 54 sand mud

Claims (3)

An ammo transplant base sheet that germinates and settles sea eels, which is attached to the transplant mat, a biodegradable reinforcement net that covers the surface of the transplant mat and imparts irregularities, and the biodegradable reinforcement net An ammo field construction method using an ammo transplant base sheet composed of a weight body ,
The base sheet for transplanting sea eels is installed in a natural sea bream field,
Natural roots of eelgrass is fixing entangled biodegradable reinforcing net or transplantation mat by eelgrass seeds germinate naturally fall in eelgrass beds of,
Next, move the sea cucumber transplantation base sheet, where the sea cucumber has settled, to the seabed of the relocation destination ,
How to create an Amamo field. The method for building a eelgrass field according to claim 1, wherein the mat for transplantation is biodegradable and comprises vegetable fibers having voids inside. The method for building an ammo field according to claim 1 or 2, wherein the weight body is a flexible member.

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