Marine plant culture and marine plant culture method

Abstract

To provide a marine plant culture body which can be laid on the bottom of the sea without trouble, is biodegradable, and does not hinder the germination and rooting of marine plants, and to provide a method for culturing marine plants.SOLUTION: The marine plant culture has a bag body composed of a sheet made of regenerated cellulose and a mixture of a seed body of a marine plant selected from the group consisting of a seed or a germinating body of seaweed and a spore or a germinating body of seaweed and a culture medium holding the seed body.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a marine plant culture and a method for culturing a marine plant. [Background technology]

[0002] Seaweed beds not only provide a suitable habitat for a variety of organisms, including benthic organisms, fish, and plankton, but also contribute to environmental improvements such as water purification.

[0003] In recent years, the effects of climate change have been noticeable, suppressing algae growth and causing seaweed beds to be washed away by typhoons. Furthermore, there have been cases where the balance between the amount of algae eaten by sea urchins and fish and the amount of algae that can be grown has been disrupted, resulting in coastal barrenness and the disappearance of algae. As a result, attempts have been made to artificially increase the number of seaweed beds in areas where algae have declined.

[0004] For example, eelgrass beds are known to have a significant function in raising young thanks to the flowering plant eelgrass and the microalgae that attach to it, and in recent years their conservation and restoration (creation) have become important themes.

[0005] For this reason, seeding sheets such as a seeding sheet in which seeds are fixed to a sheet member made of biodegradable resin (see, for example, Patent Document 1), or a seaweed propagation base in which seaweed seeds are placed on a biodegradable porous support plate and a biodegradable covering net is placed on top of the seeds (see, for example, Patent Document 2) are produced, and the seeding sheet is rolled up and lowered to the seabed for laying. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 3183829 [Patent Document 2] Patent No. 4341025 Summary of the Invention [Problem to be solved by the invention]

[0007] However, at present, the work of laying the sheets on the seabed is basically done manually by divers, which requires specialized skills and a great deal of labor, resulting in high costs.

[0008] The present invention has been proposed in light of the current situation, and an object of the present invention is to provide a marine plant culture that can be laid on the seabed without hassle, is biodegradable, and does not interfere with the germination or rooting of marine plants, as well as a marine plant culture method using the same. [Means for solving the problem]

[0009] [1] A bag made of a sheet of regenerated cellulose, and A marine plant culture comprising a mixture of a marine plant seed body selected from the group consisting of seaweed seeds or germinated bodies, and seaweed spores or germinated bodies, enclosed inside the bag, and a culture medium for holding the seed body. [2] The marine plant culture described in [1], wherein the regenerated cellulose is cuprammonium rayon. [3] The marine plant culture according to [1] or [2], wherein the sheet is a nonwoven fabric. [4] A method for culturing a marine plant, characterized by using the marine plant culture according to any one of [1] to [3]. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a marine plant culture and a method for culturing marine plants that can be laid on the seabed without much effort, are biodegradable, and do not interfere with the germination or rooting of marine plants. [Brief explanation of the drawings]

[0011] [Figure 1]1 is a cross-sectional perspective view showing one example of the configuration of a marine plant culture body of the present invention. [Figure 2] FIG. 1 is a perspective view showing a state in which a plurality of marine plant culture bodies of the present invention are connected together. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an exemplary embodiment of the present invention (hereinafter abbreviated as "the present embodiment") will be described in detail. The present invention is not limited to the present embodiment, and various modifications can be made within the scope of the gist of the present invention. In the present specification, the upper and lower limits of each numerical range can be combined arbitrarily.

[0013] FIG. 1 is a cross-sectional perspective view showing an example of the structure of a marine plant culture body of the present invention. The marine plant culture 1 of the present invention is characterized by having a bag 10 made of a sheet of regenerated cellulose, and a mixture of a marine plant seed 20 selected from the group consisting of seaweed seeds or germinated bodies, and seaweed spores or germinated bodies, enclosed inside the bag 10, and a culture medium 30 for holding the seed 20. Such a marine plant culture medium 1 can be laid on the seabed without much effort, is biodegradable, and does not hinder the germination or rooting of marine plants.

[0014] <Marine plants> Marine plants are seaweeds and other marine plants that live in the ocean, and any marine plants that produce seeds or spores can be used. Specific examples of marine plants include eelgrass, Sargassum, Sargassum, Ecklonia cava, and kelp.

[0015] <Seed body> The marine plant seed bodies 20 are seaweed seeds or germlings, seaweed spores or germlings, and specifically include seaweed seeds, roots or stems including growth points, seaweed spores, sporophytes, zoospores, gametes, seaweed reefs including growth points, etc.

[0016] <Bag body> The bag 10 is made of a sheet of regenerated cellulose. The sheet made of regenerated cellulose may be any sheet containing regenerated cellulose, and may be a fabric (woven fabric, knitted fabric, nonwoven fabric, etc.) containing fibers (short fibers, long fibers, hollow fibers, etc.), a film, a porous membrane (flat membrane), etc.

[0017] Furthermore, when the sheet contains fibers, the fibers may be textured yarns, such as loosely twisted yarns to tightly twisted yarns, false twist textured yarns, air jet textured yarns, push-textured yarns, knit-de-knit textured yarns, and spun yarns such as ring spun yarns, open-end spun yarns, and air jet spun yarns.

[0018] Among regenerated cellulose fibers, cuprammonium rayon (also known as cupra or Bemberg (registered trademark, manufactured by Asahi Kasei Corporation)) is preferred in terms of functional expression because it has a porous structure on the fiber surface in addition to the presence of a large amount of amorphous matter on the surface. Cuprammonium rayon biodegrades at a rate that does not interfere with the germination or growth of plants.

[0019] Regenerated cellulose fibers can be either continuous or short fibers, but continuous fibers are preferable because they have better lint-free properties than short fibers, have fewer fiber ends and fluff, and are less likely to fall off from nonwoven fabrics. Furthermore, because they are formed by self-adhesion through hydrogen bonding and three-dimensional entanglement through high-pressure liquid flow, they tend to have strong interfiber bonding and entanglement.

[0020] The fiber diameter of the regenerated cellulose fibers is preferably 5.0 μm or more and 20.0 μm or less, more preferably 7.0 μm or more and 18.0 μm or less, even more preferably 9.0 μm or more and 16.0 μm or less, and even more preferably 10.0 μm or more and 16.0 μm or less.

[0021] When the sheet constituting the bag body 10 is a nonwoven fabric containing regenerated cellulose fibers, the nonwoven fabric is preferably produced using a binderless method such as hydroentangling or needle punching, which does not contain a binder. In particular, hydroentangling makes it easy to produce a nonwoven fabric that is resistant to delamination because the fibers are sufficiently entangled with each other.

[0022] When the sheet constituting the bag body 10 is a nonwoven fabric containing regenerated cellulose fibers, the basis weight of the nonwoven fabric is 5 g / m 2 More than 100g / m 2 Preferably, it is 10 g / m or less. 2 More than 40g / m 2 More preferably, it is 15 g / m or less. 2 More than 30g / m 2 It is even more preferable that the weight is less than this range. By keeping the weight per unit area within this range, biodegradability and retention of the seed material 20 and the like are excellent. The tensile strength of the nonwoven fabric when dry is preferably 5 N / 5 cm width or more in both the warp and weft directions, and more preferably 10 N / 5 cm width or more. In addition, it is preferable that the strength balance in the warp and weft directions is within 2.5 times.

[0023] When the sheet constituting the bag body 10 is a nonwoven fabric containing regenerated cellulose fibers, the thickness of the nonwoven fabric is preferably 0.10 mm to 0.30 mm, more preferably 0.15 mm to 0.25 mm. By keeping the thickness within this range, biodegradability and retention of the seed body 20 and the like are excellent.

[0024] Furthermore, when the sheet constituting the bag body 10 is made of a fibrous fabric or nonwoven fabric, various nutrients (fertilizers) such as nitrogen, phosphorus, iron, etc., hormones that assist algae growth, bitter substances such as tannins that prevent feeding damage, and other substances may be attached to or impregnated into the sheet in advance. Furthermore, for example, when creating a seagrass bed, the seagrass may be eaten away by feeding-damaging organisms, and the sheet may be impregnated with a chemical agent that combats these feeding-damaging organisms.

[0025] The fibers constituting the sheet may be biodegradable regenerated cellulose or any other known compound known to be biodegradable, such as aliphatic polyester, aliphatic polyester amide, aliphatic / aromatic polyester, polyvinyl alcohol, aliphatic polyamide, polyoxyalkylene, etc. Newly developed biodegradable fibers may also be used.

[0026] For example, when the sheet constituting the bag body 10 is a fabric containing regenerated cellulose fibers, the fibers can be in a blended form such as blended spinning (cotton blend, fleece blend, sliver blend, core yarn, silospun, silofil, hollow spindle, etc.), interlaced blend, twisted, fancy twisted yarn, covering (single, double), composite false twist (simultaneous false twist, pre-twisted false twist, differential elongation false twist, phase difference false twist, false twist processing followed by post-blending), etc.

[0027] <Culture medium> The culture medium 30 holds the marine plant seed bodies 20 and allows them to germinate and take root on the seabed. The culture medium 30 is not particularly limited in material as long as it can perform the function, but for example, if the marine plant is a sandy mud seaweed or algae, the culture medium 30 can be a bottom sediment made of sand and mud, and if the marine plant is a rocky reef seaweed or algae, the culture medium 30 can be a bottom sediment made of gel (polymer viscous material).

[0028] As the sand and mud, fine soil such as Kanuma soil, river sand, mountain sand, leaf mold, clay loam, sandy loam, bark compost, and peat moss can be used.

[0029] The reef may be made of stones, sand, or various types of shells such as oyster shells.

[0030] The gelling agent used to prepare the gel is not particularly limited and may be either natural or artificial. Examples of such gelling agents include gellan gum, agar, gelatin, silica gel, acrylamide, glucomannan, methylcellulose, gum arabic, starch, sodium alginate, carrageenan, bentonite, alginate, collagen, fused silica, water-soluble starch, polyacrylate, cellulose, polyethylene glycol, polyethylene oxide, polyvinyl alcohol, dextran, and polysaccharides. These gelling agents may be used alone or in combination of two or more. Among these, cellulose, carboxymethylcellulose, and sodium alginate are preferred as gelling agents.

[0031] Furthermore, when the culture medium 30 is a gel and the seed body 20 is a spore (sporophyte, zoospore, gametophyte), the spores move through the gel to be fertilized, so it is preferable that the gel is soft enough to allow the spores to move.

[0032] The moisture content of the gel is preferably between 200% and 5000% in the initial state immediately after installation on the seabed, which prevents the spores from drying out and allows them to move through the gel, promoting their implantation and germination.

[0033] The culture medium 30 may further contain, in addition to the sand, mud, reef, and gel described above, water-retaining materials, admixtures, various nutrients (fertilizers), various chemicals such as pesticides, and the like.

[0034] Then, the mixture of the culture medium 30 and the seeds 20 of the marine plant is placed inside the bag 10, and the opening of the bag 10 is closed to obtain the marine plant culture medium 1 of the present invention.

[0035] The method for closing the opening of the bag body 10 is not particularly limited, but examples thereof include a method of joining the opening of the bag body using sewing, heat sealing, glue, etc., or a method of tying the opening of the bag body 10 with a string. In addition, the member for closing the opening of the bag body 10 is also preferably made of a biodegradable material.

[0036] In addition, it is preferable to divide the bag 10 into multiple small spaces by partially or entirely closing it by sewing, gluing, or the like so that the culture does not become too uneven inside the bag 10. In this case, the spaces may not be completely closed, but may be made into semi-passage-shaped pockets.

[0037] The size and shape of the marine plant culture medium 1 of the present invention, i.e., the size and shape of the bag body 10, are not particularly limited and can be determined appropriately according to the type of marine plant and the conditions of the seabed (topography, water depth, ocean currents, etc.).

[0038] Specifically, the shape of the marine plant culture body 1 may be, for example, circular or rectangular in plan view, and may be flat or dumpling-like in three dimensions.

[0039] 2, multiple marine plant cultures 1 may be joined together to form a single large structure, such as a fishing net or a net used for seaweed cultivation, which is easy to handle. This allows marine plant cultures 1 to be laid out efficiently over a wide area. Furthermore, the structure can be laid out to conform to the topography of the seabed.

[0040] 2, multiple marine plant culture bodies 1 are connected together using a rope 2, but this is not limiting and the bags 10 may be sewn together or multiple marine plant culture bodies 1 may be attached to a sheet. Furthermore, members such as ropes used to connect multiple marine plant culture bodies 1 are preferably made of biodegradable materials.

[0041] Next, the method for installing the marine plant culture body 1 of the present invention on the seabed is not particularly limited, and examples thereof include throwing it into the sea or laying it down by towing it from a boat. This allows for easy installation on the seabed without the need for large-scale work by divers. For example, by towing it down from a boat and laying it down, construction over a wide area can be carried out while significantly reducing the number of divers required.

[0042] Furthermore, since most of the marine plant culture 1 is made of biodegradable materials, it will naturally disintegrate after a predetermined period of time has passed since it was installed, and it will have little impact on the natural environment and ecosystem.

[0043] If the time until the bag 10 naturally collapses is too long compared to the germination period of the seed body 20, even if the seeds germinate inside the bag 10, they will be inhibited by the bag 10 and will not grow, making it difficult for them to take root on the seabed. On the other hand, if the time until the bag 10 naturally collapses is too short compared to the germination period of the seed body 20, the bag 10 will collapse before the seeds 20 germinate, and the culture medium 30 and seeds 20 inside will be carried away by ocean currents, making it difficult for them to take root on the seabed.

[0044] In the marine plant culture medium 1 of the present invention, by constructing the bag body 10 from regenerated cellulose, the period until it disintegrates in the sea is approximately one month, which provides an ideal balance with the period until the seed body 20 germinates and takes root.

[0045] Even before the bag 10 completely collapses, by the time the seed body 20 germinates, at least a part of the bag 10 will have collapsed, become holed, or become weak, so it will not hinder germination or rooting. This allows the marine plant seed body 20 to efficiently take root on the seabed.

[0046] Furthermore, before placing the marine plant culture body 1 on the seabed, the culture medium 30 may be soaked in fresh water, thereby impregnating the culture medium 30 with fresh water. This can improve the germination rate of the seeds 20.

[0047] The effects of the present invention are also applied to a marine plant culture method using the marine plant culture material 1 of the present invention described above.

[0048] Although the embodiment of the present invention has been described above, the present invention is not limited to this and can be modified as appropriate within the scope of the invention. [Example]

[0049] Next, the present embodiment will be described in more detail with reference to examples and comparative examples. However, the present embodiment is not limited to the following examples as long as they do not deviate from the gist of the present invention.

[0050] Example 1 Ten eelgrass seeds were mixed with soil as a culture medium. This mixture was placed in a bag (inner dimensions 100 x 100 mm) made of regenerated cellulose nonwoven fabric (Asahi Kasei Corporation, cupra nonwoven fabric "Benliese (registered trademark)") and the opening of the bag was tied with string to create a ball-shaped marine plant culture. Two identical samples were produced. The nonwoven fabric (SJ401) used for the bag body is a mesh made by hydroentangling, with a basis weight of 40 g / m 2 The thickness was 0.50 mm, the fiber diameter was 12 μm, and the tensile strength in the dry state was 24 N / 5 cm width in the warp direction and 19 N / 5 cm width in the weft direction.

[0051] Example 2 The bag body is made of flat, hydro-entangled ultra-fine yarn, with a basis weight of 38 g / m 2 Two marine plant cultures were prepared in the same manner as in Example 1, except that a nonwoven fabric (TA38G) of 0.26 mm thick, 5 μm in fiber diameter, and with a dry tensile strength of 37 N / 5 cm width in the warp direction and 23 N / 5 cm width in the weft direction was used.

[0052] Example 3 The bag body is made of a fine mesh with a water-flow entanglement, and the weight is 23g / m 2 Two marine plant cultures were prepared in the same manner as in Example 1, except that a nonwoven fabric (SJ231) of 0.27 mm thick, 12 μm fiber diameter, and a dry tensile strength of 25 N / 5 cm width in the vertical direction and 5 N / 5 cm width in the horizontal direction was used.

[0053] Example 4 The bag body is flattened by hydroentangling, and has a basis weight of 38 g / m 2 Two marine plant cultures were prepared in the same manner as in Example 1, except that a nonwoven fabric (SE384) with a thickness of 0.32 mm, a fiber diameter of 12 μm, and a dry tensile strength of 37 N / 5 cm width in the vertical direction and 22 N / 5 cm width in the horizontal direction was used.

[0054] Example 5 The bag body is made of a fine mesh created by hydroentanglement, with a basis weight of 25 g / m 2 Two marine plant cultures were prepared in the same manner as in Example 1, except that a nonwoven fabric (SH25G) with a thickness of 0.18 mm, a fiber diameter of 12 μm, and a dry tensile strength of 17 N / 5 cm width in the vertical direction and 8 N / 5 cm width in the horizontal direction was used.

[0055] Example 6 The bag body is made of a fine mesh created by hydroentanglement, with a basis weight of 18g / m 2 Two marine plant cultures were prepared in the same manner as in Example 1, except that a nonwoven fabric (SJ18G) with a thickness of 0.13 mm, a fiber diameter of 12 μm, and a dry tensile strength of 19 N / 5 cm width in the vertical direction and 4 N / 5 cm width in the horizontal direction was used.

[0056] Example 7 The bag body is flattened by hydroentangling, and the basis weight is 14g / m 2 Two marine plant cultures were prepared in the same manner as in Example 1, except that a nonwoven fabric (SN140) of 0.07 mm thick, 12 μm fiber diameter, and a dry tensile strength of 27 N / 5 cm width in the vertical direction and 6 N / 5 cm width in the horizontal direction was used.

[0057] (Comparative Example 1) The bag body has a basis weight of 40g / m 2 Two marine plant cultures were prepared in the same manner as in Example 1, except that the polylactic acid sheet (film) was used.

[0058] (Comparative Example 2) The bag has a basis weight of 90g / m 2Two marine plant cultures were prepared in the same manner as in Example 1, except that the hemp fabric was used.

[0059] Soil was placed in a planter, and one of the marine plant cultures produced in Examples 1 to 7 and Comparative Examples 1 and 2 was buried in the soil and the other placed on top of the soil, and seawater was then filled in from above. In this state, the marine plant culture was left outside and the state of the culture was observed over time.

[0060] As a result, in all of Examples 1 to 7, it was confirmed that the seeds had sprouted one month after the start of the test. The bags had also begun to decompose. Two months after the start of the test, the bags had completely decomposed, and sprouts and roots had grown outside and were able to take root in the soil.

[0061] In contrast, in Comparative Examples 1 and 2, although the seeds germinated inside the bags, the bags did not decompose, and the seeds were unable to grow shoots or roots outside the bags and take root in the soil. [Industrial Applicability]

[0062] The marine plant culture according to the present invention can be laid on the seabed without much effort, is biodegradable, and does not interfere with the germination or rooting of marine plants, making it widely usable as a marine plant culture. [Explanation of symbols]

[0063] 1 Marine plant culture 10 Bag body 20 species 30 Culture medium

Claims

1. A bag made of a sheet of regenerated cellulose, and A marine plant culture comprising a mixture of a marine plant seed body selected from the group consisting of seaweed seeds or germinated bodies, and seaweed spores or germinated bodies, enclosed inside the bag, and a culture medium for holding the seed body.

2. 2. The marine plant culture of claim 1, wherein the regenerated cellulose is cuprammonium rayon.

3. 3. The marine plant culture according to claim 1, wherein the sheet is a nonwoven fabric.

4. A method for culturing a marine plant, comprising using the marine plant culture according to claim 1.

Images