JP6361966B2 - Formation method of seaweed beds - Google Patents

Description

  The present invention relates to a method for forming an algae field in water in which the food pressure on algae by aquatic organisms changes over time.

  The algae field formed in the water is formed so as to spread over a certain area by the balance between the growth of algae constituting the algae field and the intake by the feeding activity of the aquatic organisms. Algae grow to reach the maturity period (the time when spores are released) during the period when fish intake decreases (hereinafter also referred to as low feeding pressure), thereby reducing the risk of fish feeding. While next-generation breeding and growth will take place. As a result, the balance between the growth of algae and the amount of food consumed by the fish is maintained, and the algae ground with a certain extent is maintained.

  However, the period when the food pressure is high is prolonged due to environmental changes, and such a period (a period when the amount of food intake is high) and the algae maturation period may overlap. In such a case, the growth of the next generation of algae is inhibited by feeding by fish, and a phenomenon occurs that the balance between the growth of algae and the amount of food consumed by fish collapses and the algae ground disappears (hereinafter also referred to as firewood burning). ing.

  When forming a seagrass bed again in the water in which such salmon burning has occurred, it is required to grow algae without being affected by feeding by fish. As a method for cultivating algae in this way, for example, an algae reef in which algae spores and algae themselves adhere to a reef material is installed on the bottom of the water to form an artificial algae field, and algae on the reef material is cultivated. A method for forming a protection region by covering the region with a net-like member has been proposed (see Patent Document 1). In such a method, since the organisms that feed on the algae do not enter the protected area, the algae on the alga reef are not affected by the feeding activity of the aquatic organisms, and the growth of the algae and the formation of the algae field are efficiently performed. Can be performed.

JP 2007-6796 A

  However, when the above-described protected area is formed, the outside of the protected area is affected by the feeding activity of aquatic organisms. For this reason, if spores are released from the algae in the protected area at a high pressure, even if the spores adhere to the bottom of the water outside the protected area, it is difficult to grow the algae outside the protected area. It is not possible to form a seaweed bed outside.

  Then, this invention makes it a subject to provide the formation method of an algae field which can form an algae field also in the outer side of the protection area | region of the algae covered with the net-like member.

The method for forming an algae field according to the present invention is a method for forming an algae field in water in which the food pressure on algae by aquatic organisms changes over time, wherein the spore or larvae are formed at a time when the food pressure is low. A protective area covered with a net-like member is formed in the growing area for growing the first algae that reaches the maturity stage to disperse the embryo and the perennial second algae, and the first algae that are the first algae and the second algae are formed in the protected area. It is characterized by nurturing diatom chrome .

  According to such a configuration, since the first algae reach the maturity stage at a low feeding pressure, the next generation of the first algae grows even if spores or young embryos are diffused in the region outside the protected region. Thereby, the algae ground of the first algae (hereinafter also referred to as the first algae ground) can be formed outside the protection region. In addition, the second algae, which is a perennial algae, is grown in the protected area. Can also be formed). That is, the formation and expansion of the first algae basin can be performed outside the protected area, and the second algae basin can be maintained throughout the year in the protected area.

  According to such a configuration, the first algae are cultivated in addition to the second algae in the protected area, so that the first algae are not affected by the feeding activity of aquatic organisms until the first algae reaches the maturity stage. Can be nurtured. Thereby, formation of the 2nd seaweed bed outside the protection field can be performed efficiently.

  As described above, according to the present invention, it is possible to provide a method for forming an algae field that can form an algae field even outside the protected area of algae covered with a net-like member.

The perspective view which shows the state by which the net-like member was installed in the reef material used with the formation method of the seaweed bed concerning this embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to FIG.

  The method for forming an algae field according to the present embodiment is to form an algae field in water in which the food pressure on algae by aquatic organisms changes over time. In addition, the method for forming a seaweed bed according to the present embodiment, as an aquatic organism, in the sea where herbivorous fish such as Aigo, Japanese hornet, Japanese bream, Nazidai, Kawahagi, Umadurahagi inhabit the sea, in particular, at least of Aigo, Japanese damselfish, and Japanese sea bream. It is suitably applied when algae beds are formed in the sea where any one of them lives.

  The change of the food pressure with respect to algae becomes remarkable, for example, when the amount of seaweed in the surrounding sea area changes. Specifically, in the situation where many seaweeds such as seaweed exist in the surrounding sea area in early spring, the pressure of algalivorous fish that eat seaweed is dispersed, resulting in a low pressure. On the other hand, from early spring to summer, the spring seaweed ground (wakame etc.) disappears as the water temperature rises, so the amount of seaweed in the surrounding sea area greatly decreases and the food pressure increases relatively. Furthermore, when the water temperature gradually decreases from a period when the water temperature is relatively high (for example, a period of 20 ° C. or higher), the food pressure against algae further increases. Decrease. The period when this pressure increases is prominent at the beginning of autumn when the seaweeds in the surrounding sea area decrease and the water temperature decreases.

  In the method for forming an algal field according to the present embodiment, a predetermined region (also referred to as a growth region) is a first algae that reaches a maturity stage in which spores or young embryos are released at a time when the feeding pressure is low, and a perennial second algae. Raise with. The growing region is not particularly limited, and the surface of the artificial reef material and the water bottom are used. In the present embodiment, as shown in FIG. 1, the surface of the artificial reef material A and the water bottom L around the artificial reef material A serve as a growing region, and an algae bed is formed in the growing region.

  In addition, a protective region covered with the mesh member B is formed in the growing region. In the present embodiment, the protection area is formed on the reef material A by installing the mesh member B on the reef material A. As the reticulated member B, a member having a stitch that does not allow underwater organisms (specifically, at least the above-mentioned herbivorous fish) to enter the protected area is used. In the protected area, at least second algae are grown. In the present embodiment, the first algae and the second algae are grown in the protected area.

  The first algae is preferably one that diffuses zoospores as spores in the mature period. Since the zoospores are dissipated, the zoospores are dissipated to the periphery of the protected area, and therefore, the expansion of the algae ground (specifically, the first algae ground described later) can be performed efficiently. Moreover, it is preferable that the first algae reach the maturity stage immediately before the time when the food pressure increases. As a result, the first algae can spend a period of high food pressure in a state that is hard to be eaten by aquatic organisms (for example, the size and form that aquatic organisms are difficult to eat). In this case, the formation of the seaweed beds (specifically, the first seaweed bed described later) can be efficiently performed.

  As the first algae, any one or a plurality selected from perennial hondawala, hondawala and kombu can be used. Examples of Honda Walla include temperate Mametawala, Yatsuma Tamoku, Akamoku and other southern Kirebamok, Magirimok, Futaemok, Tsukushimoku and the like. Examples of the kombu include wakame and (southern) antome. In particular, antokume has a longer growth period than seaweeds, and the spread of the zoospores is wider than that of the larvae of the honda, so the rate of expansion of the seaweed beds is high. In addition, Antokume has a structure in which the temporary roots are firmly attached to the reef, so that it is relatively strong in waves and can grow from a shallow water area to a deep sea area with a relatively small amount of light. For this reason, an artificial seaweed bed creation (specifically formation of the 1st seaweed bed mentioned below) can be performed efficiently by using antokume as the first algae.

  The second algae are cultivated over the course of the year without meeting the damage of fish in the protected area, but are preferably algae that release zoospores as spores in the mature period. As the zoospores are released, the zoospores are released to the periphery of the protected area, so that the second algae can be grown around the protected area depending on the maturation period and food pressure of the second algae.

  As the second algae, any one or more selected from arame, kajime, kurome, crane arame, and perennial Honda Walla can be used. In particular, the spread rate of seaweed beds is high in chrome as the zoospores have a wider diffusion range than the young embryos. Further, chrome is a structure in which the temporary roots are firmly attached to the reef, so that it is relatively strong in waves and can grow from a shallow sea area to a deep sea area with relatively little light intensity. For this reason, by using chrome as the second algae, artificial seaweed bed construction (specifically, formation of seaweed beds in or around the protected area) can be performed efficiently.

  Next, the flow in which the seaweed beds are formed by the method for forming the seaweed beds according to the present embodiment will be described. Below, the case where an antume is used as a 1st algae and the chrome is used as a 2nd algae is demonstrated.

  First, antokume (first algae) and chrome (second algae) are grown in the protected area covered with the mesh member B. As a result, a mixed seaweed bed of Antokume and Kurome is formed in the protected area. Anthrome in the protected area reaches the maturity period (specifically around August) when the food pressure by the fish is low (specifically, just before the food pressure becomes high) and releases the zoospores. The diffused zoospores adhere to the bottom L around the protected area. And the antome that grows from the zoospores has a high food pressure in a form (specifically, a size that can be observed with a microscope) that is difficult to eat by fish outside the protected area (specifically, , From September to February). Then, when the time when the food pressure is low (specifically, from March to August), an Antarctic seaweed bed (hereinafter also referred to as a first seaweed bed) is formed around the protected area.

  Here, since the Antarctic is an annual algae, the Antarctic ground that constitutes the First Algae has been temporarily suspended after the Antarctic that has matured (specifically, when the food pressure increases). Disappears. However, as mentioned above, the Antarctic zoospores are released in and around the 1st Algae at a low feeding pressure, so Ant Ants growing from the released zoospores feed on fish. A period of high food pressure is spent in a difficult form (specifically, a size that can be observed with a microscope), and a broader range of first algae fields are formed when the time of low food pressure arrives.

  On the other hand, perennial chrome remains in the protected area after the mature stage of the Antarctic, and a chrome algae field (hereinafter also referred to as a second algae field) is formed throughout the year. Specifically, the Antokume in the protection area diffuses zoospores in the protection area, but such zoospores do not grow in the protection area because of the presence of chrome in the surroundings. As a result, a black seaweed bed is formed throughout the year in the protected area.

  As described above, in the method for forming a seagrass bed according to the present embodiment, the second seaweed ground (four season seaweed ground) is formed throughout the year in the protected area, and only outside the protected area at a time when the food pressure is low. The first algae field (spring algae field) will be formed.

  As described above, according to the method for forming an algae field according to the present invention, it is possible to provide a method for forming an algae field that can form an algae field even outside the protected area of the algae covered with a mesh member. it can.

  That is, since the first algae reach the maturity stage when the food pressure is low, the next generation of the first algae grows even if spores or young embryos are released in the area outside the protected area. Thereby, the algae ground of the first algae (hereinafter also referred to as the first algae ground) can be formed outside the protection region. In addition, the second algae, which is a perennial algae, is grown in the protected area. Can also be formed). That is, the formation and expansion of the first algae basin can be performed outside the protected area, and the second algae basin can be maintained throughout the year in the protected area.

  Also, by growing the first algae in addition to the second algae in the protected area, it is possible to grow the first algae without being affected by the feeding activities of aquatic organisms until the first algae reaches the maturity stage. it can. Thereby, formation of the 2nd seaweed bed outside the protection field can be performed efficiently.

  In addition, the formation method of the seaweed bed concerning this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of this invention. Further, the configurations and methods of the plurality of embodiments described above may be arbitrarily adopted and combined (even if the configurations and methods according to one embodiment are applied to the configurations and methods according to other embodiments). Of course, it is of course possible to arbitrarily select configurations, methods, and the like according to various modifications described below and employ them in the configurations, methods, and the like according to the above-described embodiments.

  For example, in the above-described embodiment, the first algae are configured to be grown in the protection area together with the second algae. However, the present invention is not limited to this. For example, the first algae are outside the protection area. It may be raised. For example, by placing the first algae in the mature stage around the protected area at a low phagocytic pressure, spores or young embryos are released around the protected area even outside the protected area. A seaweed bed can be formed.

  Moreover, in the said embodiment, although the Antarctic which is an annual algae is used as a 1st algae, it is not limited to this, You may use a perennial algae as a 1st algae.

  Moreover, in the said embodiment, although the net-like member B is installed on the reef material A and the protection area is formed, it is not limited to this, and the net-like member B is installed on the water bottom L and the protection area is It may be formed.

  A ... reef material A, B ... mesh member, L ... water bottom

Claims (1)

A method for forming an algae basin that forms an algae basin in water in which the pressure on algae by aquatic organisms changes over time,
Forming a protective region covered with a net-like member in a growing region for growing a first algae that reaches the maturity stage to disperse spores or young embryos at a time when the phagocytic pressure is low, and a perennial second algae; A method for forming an algae basin characterized by cultivating antokume as a first algae and chrome as a second algae.

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