JPS60120927A - Diatom precipitated bank and its production - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Subject of the Invention] The present invention relates to a diatom-depositing reef for depositing and multiplying diatoms essential for raising juvenile fish and shellfish, and a method for producing the same.

[Background of the invention]

Today, with 200 nautical miles of ocean territory now a reality, the promotion of coastal fisheries has become an urgent task. In order to promote coastal fishing, it is necessary to create a good habitat suitable for fish and shellfish, and to do this, it is necessary to increase the number of good seaweed beds that serve as feeding grounds for fish and shellfish. The inventor of this application previously invented a seaweed bed propagation reef for growing seaweed beds (patent application filed in 1973).
No. 6-172620). The key point of this seaweed bed propagation reef is to embed crystal blocks of ferrous sulfate or ferric sulfate on the surface of the concrete base while the concrete is uncured, and as the concrete hardens, the crystals When this seaweed bed propagation reef is deposited, it has a structure in which a number of depressions are formed on the surface formed by the body mass dissolving in the water in the concrete, which has a permeable layer of ferrous sulfate or ferric sulfate. It has been confirmed that many algae grow. In particular, it is extremely effective for the growth of green algae and brown algae, but it is not sufficient for the deposition and proliferation of diatoms, which are essential for the spawning, hatching, and subsequent growth of young fish and shellfish during their initial life stage. It does not have any effect. The reason for this is that diatoms are delicate organisms, and their survival and proliferation are greatly affected by the environment. It is particularly sensitive to alkalis in concrete and cannot live on the surface of concrete structures. In addition, it has been confirmed that diatoms are weak not only in alkalinity but also in acidity, and the reason why diatoms cannot adhere to and survive on the seaweed bed breeding reef is that
This is thought to be due to the acidity contained in iron or ferric sulfate.

Therefore, currently, natural crushed stones are deposited to create a habitat for diatoms, but even if natural crushed stones are deposited in shallow waters where diatoms live, rough waves and 1. The problem was that they were washed away by fast-moving ocean currents.

[Object of the Invention] The present invention has been made in view of the above-mentioned points. Natural stones, which are deposited in shallow waters with rough waves and suitable for diatoms to live in, are exposed on the surface of reef blocks, and are exposed to rough waves and ocean currents. The purpose of the present invention is to provide a diatom deposited reef that will not be washed away and a method for producing the same.

[Summary of the invention]

The key point of the present invention is to expose natural stone such as andesite, on which diatoms prefer to deposit, from the surface of the concrete block body,
The present invention provides a diatom deposited reef in which diatoms are deposited on the surface of natural stone, and a method for producing the same.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

FIG. 1 is a perspective view showing a part of a diatom deposited reef according to the present invention, and FIG. 2 is a cross-sectional view. As shown in the figure, a large number of natural stones 2 are exposed from the surface of a concrete block 1. As a method of exposing this natural stone, a method of embedding the natural stone 2 in the concrete block 1 before the concrete has yet to harden can be considered, but in order to mass-produce the diatom deposited block, it is manufactured by the method described below.

FIG. 3 and FIG. 4 are diagrams showing the manufacturing process of the diatom deposited reef block. As shown in Figure 3, first, block formwork 1
A plate-like body 12 made of paper or the like impregnated with a concrete hardening retardant that retards the hardening of concrete is placed on the surface of the hardening concrete. A commercially available concrete hardening retarder that retards the hardening of concrete is sufficient, and paper impregnated with this concrete hardening retarder is also commercially available. Although it is possible to use the above-mentioned commercially available paper for the plate-like body 12, it is more effective to use a thick felt-like paper as the plate-like body 12 in order to increase the amount of concrete hardening retardant impregnated. It is.

When concrete consisting of crushed stone 13, such as andesite, on which diatoms are likely to deposit, as well as sand and cement 14, is poured over the plate-shaped body 12, the moisture contained in the concrete 1 and the plate-shaped body 12 are impregnated. Concrete 1 to the retarder react with each other, and the hardening of the cement to the position shown by the dashed line A is delayed. When the cement at a position deeper than the dashed-dotted line A has hardened, the formwork 11 and the plate-shaped body 12 are peeled off and the surface is washed with water. Cement, sand, stones, etc. are washed away by the water, creating a surface as shown in the cross-sectional view in Figure 4.

When a concrete block body with the above structure is sunk in shallow water, the natural stone part exposed from the surface of concrete block 1 becomes a neutral part that is neither acidic nor alkaline, and it is confirmed that many diatoms are deposited thereon. has been done. In particular, it has been confirmed that andesite, which has a hardness of 16, has a remarkable effect on the deposition of diatoms.

In the above example, the formwork 11 and the plate-like body 12 impregnated with concrete hardening retarder are peeled off and then washed with water. If the block is submerged in the sea, even if the washing step is omitted, the block surface will be washed by seawater and the block will look like the one shown in FIG. 4.

As explained above, according to the above embodiment, a plate-like body impregnated with concrete 1 to a curing retarder is placed on the formwork 11,
Concrete 1 made of natural stone, which diatoms like to deposit
A diatom-deposited reef on which diatoms prefer to deposit can be manufactured by a simple process of casting and curing the mold, peeling off the formwork 11 and the plate-shaped body, and submerging it in the sea. In addition, the diatom reefs produced in this way can be made into a frustum shape as shown in Figure 5, for example, to increase their stability and allow them to be used in rough seas or ocean currents, such as when natural crushed stone is deposited. It does not get washed away by fish, and it is highly effective in creating nursery grounds for young fish, which is essential for creating artificial fishing grounds.

〔Effect of the invention〕

As explained above, the diatom-deposited reef according to the present invention allows natural stones, which diatoms prefer to deposit, to be sprayed onto the concrete block surface, which has a stable structure in terms of strength and weight. When placed in rough, shallow waters, it has an excellent effect on the deposition of diatoms.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing a part of the diatom deposited reef block, Figure 2
The figure is a sectional view, FIGS. 3 and 4 are views showing the manufacturing process, and FIG. 5 is a perspective view showing an example of a diatom deposited reef. 1-m-concrete block, 2-m-natural stone, 1
1-m-frame, 12-m-plate impregnated with concrete hardening retarder, 13-m=natural crushed stone, 14-11 sand. cement. Applicant Tokyu Musashi Industries Co., Ltd. Agent Patent Attorney Takashi Kumagai Figure 1 Figure 2 Figure 3 Figure 4a

Claims (3)

[Claims] (1) A diatom-deposited reef consisting of a concrete block body, characterized in that natural stone is exposed on the surface of the concrete block body. (2) A plate impregnated with a concrete hardening retardant is laid on the formwork, concrete made of cement, sand, and natural stone is poured onto the plate, and after the concrete has hardened, the formwork is and a diatom-deposited reef characterized by peeling off the plate-like body and then washing the professional walking surface with water to remove unhardened cement so that the surface of many natural stones is exposed from the surface of the concrete block. manufacturing method. (3) The method for manufacturing a reef according to claim 2, characterized in that crushed stone, such as andesite, on which diatoms prefer to deposit is used as the natural stone contained in the concrete.