JP7474427B2 - Marine fertilizer, and manufacturing and installation methods for the same - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Act Research on marine fertilization materials, and manufacturing and installation methods thereof was disclosed at a master's thesis interim presentation held at Hiroshima University, a national university corporation, on July 4, 2019. Research on marine fertilization materials, and manufacturing and installation methods thereof was disclosed at the 27th (2019) Seto Inland Sea Research Forum in Hiroshima, held at the Nishi Ward Community Center in Hiroshima City from September 5 to 6, 2019.

The present invention relates to marine fertilizers, and manufacturing and installation methods for the marine fertilizers.

Traditionally, herbivorous bivalve mollusks such as clams have been widely enjoyed in the Japanese diet, from being found on the dinner tables of ordinary households to being served in restaurants.

However, the catch of clams caught in tidal flats and other areas has been declining in recent years. This is thought to be due to oligotrophy caused by a lack of nutrients in seawater, such as nitrogen, phosphorus, and iron.

Therefore, several attempts have been proposed to improve the oligotrophic conditions in the areas where bivalve mollusks grow, thereby restoring the bivalve mollusks' catches.

In particular, it has been described that a fertilizer for promoting the growth of herbivorous bivalve mollusks, previously proposed by one of the inventors of the present application, can fatten clams, and that application of the fertilizer is expected to restore catches in comparison with control plots (see, for example, Patent Document 1).

JP 2017-158435 A

However, the above-mentioned conventional growth-promoting fertilizer materials were not sustainable because their constituent materials were mainly inorganic fertilizers. On the other hand, organic fertilizers are highly sustainable and can be expected to have a long-term fertilizing effect. In particular, organic fertilizers that use chicken manure as the main ingredient and have been fully decomposed to be recognized as so-called normal fertilizers place even less of a burden on the environment in the surrounding sea areas than organic fertilizers that are not fully matured, such as special fertilizers, and can be said to be one of the most useful fertilizing materials.

The present invention was made in consideration of such circumstances, and provides a marine fertilizer, which is a highly sustainable organic fertilizer whose main component is derived from chicken manure, and which can dissolve nutrients suitable for the growth of algae that serve as food for herbivorous bivalve mollusks, and which can effectively increase the growth and survival of bivalve mollusks, as well as a manufacturing method and installation method for the same. The fertilizer is

In order to solve the above-mentioned conventional problems, the marine fertilizer material of the present invention is (1) a compressed molded body of a mixed material containing 12 parts by weight of fermented chicken manure, 2 to 6 parts by weight of granular iron, 1 to 4 parts by weight of magnesium oxide, and an amount of water such that the moisture content of the marine fertilizer material described below is 45 to 60% by weight (excluding those that contain an amount of cement that is sufficient to solidify the entire mixed material) , and is configured to be soluble in seawater at a ratio of N/P = 10 to 30 and Fe/P = 0.001 to 0.1 .

In addition, in the manufacturing method of the marine fertilizer material according to the present invention, ( 2 ) a mixture of 12 parts by weight of fermented chicken manure, 2 to 6 parts by weight of granular iron, 1 to 4 parts by weight of magnesium oxide, and an amount of water such that the moisture content of the marine fertilizer material described below is 45 to 60% by weight (excluding those containing an amount of cement that can solidify the entire mixture) is compressed and molded to be soluble in seawater at a ratio of N/P = 10 to 30 and Fe/P = 0.001 to 0.1 .

The method for producing a sea area fertilizer material according to the present invention is also characterized in the following points.
( 3 ) The mixed material contains leaf mold and/or culture soil as auxiliary raw materials within a range in which the balance of leaching is maintained .
( 4 ) The fermented chicken manure is also characterized in that it is produced through the steps of: preparing a fermented mixture by adding a chicken manure fermentation microorganism fermentation liquid to a mixture of chicken manure and a moisture regulator having a lower moisture content than the chicken manure to adjust the moisture content to 60±5%; piling the obtained fermented mixture to promote fermentation; a turning step in which, when the temperature of the fermented mixture reaches 70°C or higher, the mixture is turned over before it reaches 80°C and the fermented mixture is again turned over; a repeating step in which the turning step is repeated until the moisture content reaches 35% or less and the temperature does not rise to 45°C or higher; and a fermented chicken manure production step in which the fermented mixture that has been through the repeating step is subjected to a further additional fermentation step as necessary to produce fermented chicken manure.
(5) The chicken manure fermentation microorganism fermentation liquid is prepared by a process comprising a step of allowing a mixture of 0.6 parts by weight of dried stevia stem powder, 0.6 parts by weight of rice bran powder, 0.6 parts by weight of dried soybean pulp powder, and 11 to 13 parts by weight of brackish water containing at least a salt-tolerant yeast to stand for a predetermined period of time; a step of placing the mixture after the step in a predetermined container and forming a weakly sterilized region in the placed mixture that is 10 cm or more from any position on the outer surface of the placed shape of the mixture and 17 cm or less from at least any position on the outer surface; and a step of placing the container containing the mixture after the step in a heating space, raising the temperature of the heating space from room temperature and normal pressure to 150 to 160°C at about 2.5 atmospheres over 45 to 60 minutes, maintaining the state of 150 to 160°C at about 2.5 atmospheres for 1 to 3 minutes, and then placing the container in the heating space. a microorganism selection step in which the temperature of the mixture is lowered to 115-125°C at about 2 atmospheres over a period of 3-5 minutes, the state of 115-125°C at about 2 atmospheres is maintained for 20-40 minutes, and the temperature of the heating space is further lowered to room temperature and normal pressure over a period of 24-30 hours to leave the microorganisms selected by heating in the mixture; a solid-liquid separation step in which the mixture that has been through the microorganism selection step is solid-liquid separated by a means that allows at least the microorganisms to transfer to a liquid phase to obtain a microorganism-containing liquid; a first fermentation step in which a sugar source is added to the obtained microorganism-containing liquid and fermented at room temperature and normal pressure for a predetermined period of time to adjust the pH of the microorganism-containing liquid to 4.5 or less and the oxidation-reduction potential to -100 mV or less; and a second fermentation step in which a stevia stem aged liquid is added to the microorganism-containing liquid that has been through the first fermentation step, and fermented until the pH is 3.1 or less to obtain a defective fermentation inhibitor.

In addition, the method for installing a marine fertilization material according to the present invention is ( 6 ) a method for installing a marine fertilization material manufactured by the marine fertilization material described in (1) above or the manufacturing method for a marine fertilization material described in any one of ( 2 ) to ( 5 ) above, comprising the steps of forming a hole in the tidal flat to the same height as the marine fertilization material and installing the material, and placing the marine fertilization material in the formed hole, and then covering the top of the marine fertilization material with a small amount of sand.

The marine fertilizer of the present invention is made of a compressed molded body of a mixed material containing 12 parts by weight of fermented chicken manure, 2 to 6 parts by weight of granular iron, 1 to 4 parts by weight of magnesium oxide, and an amount of water such that the moisture content of the marine fertilizer described below is 45 to 60% by weight (excluding those containing an amount of cement that can solidify the entire mixed material). It is configured to be soluble in seawater at a ratio of N/P = 10 to 30 and Fe/P = 0.001 to 0.1, so it is an organic fertilizer with excellent sustainability, and while its main constituent material is derived from chicken manure, it can realize the elution of nutrients suitable for the growth of algae that serve as food for herbivorous bivalve mollusks, and can also be a marine fertilizer that can effectively increase the growth and survival of bivalve mollusks.

In addition, if the magnesium oxide is added for the purpose of adjusting the elution of phosphorus derived from the fermented chicken manure, it is possible to suppress the elution of excess phosphorus while using phosphorus-rich chicken manure as one of the raw materials, and to achieve an elution ratio of nutrients suitable for algae growth.

In addition, if the material is made into a column shape measuring 10-30 cm in height and 15-30 cm in width, the marine fertilizer can be given even more sustained release properties, making it a more sustainable marine fertilizer.

In addition, if the fermented chicken manure is produced through the steps of: preparing a fermented mixture by adding a chicken manure fermentation microorganism fermentation liquid to a mixture of chicken manure and a moisture regulator having a lower moisture content than the chicken manure to adjust the moisture content to 60±5%; piling the obtained fermented mixture to promote fermentation; turning the fermented mixture when the temperature of the fermented mixture reaches 70°C or higher before it reaches 80°C and piling the fermented mixture again; repeating the turning process until the moisture content is 35% or less and the temperature does not rise to 45°C or higher; and a fermented chicken manure production process in which the fermented mixture that has been through the repeating process is subjected to an additional fermentation process as necessary to produce fermented chicken manure, then the fermented chicken manure that has been produced through the steps can be sufficiently decomposed, and the environmental load on the ocean caused by incomplete fermentation can be suppressed as much as possible.

The chicken manure fermentation microorganism fermentation liquid is prepared by mixing 0.6 parts by weight of dried stevia stem powder, 0.6 parts by weight of rice bran powder, 0.6 parts by weight of dried soybean pulp powder, and 11 to 13 parts by weight of brackish water containing at least a salt-tolerant yeast, in a step of leaving the mixture for a predetermined period of time, a step of placing the mixture that has undergone the step of leaving the mixture in a predetermined container, and forming a weakly sterilized area in the placed mixture that is 10 cm or more from any position on the outer surface of the shape of the mixture and 17 cm or less from at least any position on the outer surface, and a step of placing the predetermined container that has contained the mixture that has undergone the step of placing the mixture in a heating space, raising the temperature of the heating space from room temperature and pressure to a state of 150 to 160°C at about 2.5 atmospheres over a period of 45 to 60 minutes, maintaining the state of 150 to 160°C at about 2.5 atmospheres for 1 to 3 minutes, and then heating the heating space to a state of 115 to 120°C at about 2 atmospheres. 5°C over 3-5 minutes, maintaining a temperature of 115-125°C at approximately 2 atm for 20-40 minutes, and further lowering the temperature of the heating space to room temperature and normal pressure over 24-30 hours to leave the heat-selected microorganisms in the mixed liquid; a solid-liquid separation process in which the mixed liquid that has been through the microorganism selection process is solid-liquid separated by a means that allows at least the microorganisms to transition to a liquid phase to obtain a microorganism-containing liquid; a first fermentation process in which a sugar source is added to the obtained microorganism-containing liquid and fermented at room temperature and normal pressure for a predetermined time to set the pH of the microorganism-containing liquid to 4.5 or less and the oxidation-reduction potential to -100 mV or less; and a second fermentation process in which a stevia stem aged liquid is added to the microorganism-containing liquid that has been through the first fermentation process and fermented until the pH is 3.1 or less to obtain a defective fermentation inhibitor. This allows for more reliable fermentation of chicken manure.

In addition, according to the manufacturing method of the marine fertilizer material of the present invention, a mixture of 12 parts by weight of fermented chicken manure, 2 to 6 parts by weight of granular iron, 1 to 4 parts by weight of magnesium oxide, and an amount of water such that the moisture content of the marine fertilizer material described below is 45 to 60% by weight (excluding those containing an amount of cement that can solidify the entire mixture). It is then compressed and molded into seawater so that it can be dissolved in a ratio of N/P = 10 to 30 and Fe/P = 0.001 to 0.1. This makes it possible to produce a marine fertilizer that is a highly sustainable organic fertilizer that is mainly composed of chicken manure and can dissolve nutrients suitable for the growth of algae that serve as food for herbivorous bivalve mollusks, and can effectively increase the growth and survival of bivalve mollusks.

In addition, if the magnesium oxide is added to adjust the elution of phosphorus derived from the fermented chicken manure, it is possible to suppress the elution of excess phosphorus while using chicken manure, which is rich in phosphorus, as one of the raw materials, and to achieve an elution ratio of nutrients suitable for algae growth.

In addition, according to the method for installing marine fertilization material of the present invention, the method for installing the above-mentioned marine fertilization material or marine fertilization material manufactured by the manufacturing method for marine fertilization material includes the steps of forming a hole in the tidal flat with a height equivalent to that of the marine fertilization material and installing the material, and placing the marine fertilization material in the hole and then covering the top of the marine fertilization material with a small amount of sand. This makes it easy to install the marine fertilization material, and it is an organic fertilizer with excellent long-lasting properties, and its main component is derived from chicken manure, and it is capable of dissolving nutrients suitable for the growth of algae that serve as food for herbivorous bivalve mollusks, and it can effectively exert its effect as a marine fertilization material.

FIG. 2 is an explanatory diagram showing the difference in elution ratio (Fe/P) when the amount of granular iron used is changed. FIG. 1 is an explanatory diagram showing the difference in the elution state of each component when the amount of magnesium oxide used is changed. FIG. 13 is an explanatory diagram showing the results of a field test.

The present invention relates to a marine fertilizer, and in particular to a marine fertilizer that is a highly sustainable organic fertilizer whose main component is derived from chicken manure, and that can dissolve nutrients suitable for the growth of attached or benthic microalgae that serve as food for herbivorous bivalve mollusks, and can effectively increase the growth and survival of the bivalve mollusks.

Algae, especially phytoplankton and periphyton microalgae (hereafter simply referred to as algae), are the main primary producers in the ocean, and they are food for bivalve mollusks. Therefore, if the proliferation of algae, which serves as food for bivalve mollusks, is promoted in oligotrophic ocean areas, the proliferation of bivalve mollusks is promoted as a result.

Algae need certain nutrients to grow. These nutrients differ from those required by land crops, which require nitrogen (N), phosphorus (P), and potassium (K), and are known to have a ratio of N:Si:P:Fe=16:15:1:0.005.

However, no marine fertilizer has been provided that uses organic fertilizers, rather than chemical fertilizers, as its main component and achieves such a component elution ratio.

The marine fertilizer material according to this embodiment is characterized by its composition being a compressed molded body containing 12 parts by weight of fermented chicken manure, 2 to 6 parts by weight of granular iron, 1 to 4 parts by weight of magnesium oxide, and an amount of water such that the moisture content of the marine fertilizer material described below is 45 to 60% by weight.

The fermented chicken manure referred to here is not chicken manure obtained from the chicken coop immediately after excretion (so-called raw chicken manure), but chicken manure that has been decomposed by fermentation. The fermentation process is not particularly limited, but by going through the fermentation process described below, high-quality decomposition can be achieved.

Granular iron is a raw material that causes iron to dissolve. Granular does not mean one or several lumps of iron, but rather means that it is finer and numerous (multiple), and includes powder-like iron such as iron sand. Granular iron can have a diameter of, for example, approximately 0.05 mm to 10 mm, and specific examples that can be used include steel slag granules, iron sand, and iron powder.

The amount of granular iron used should be at least 2 parts by weight, for example 2 to 6 parts by weight, assuming that the amount of fermented chicken manure used is 12 parts by weight. Adding less than 2 parts by weight of granular iron is not preferred as this can lead to problems such as iron deficiency. By using 2 parts by weight or more of granular iron, an optimal supply of iron can be achieved.

Magnesium oxide functions as a solidifying agent in the marine fertilizer of this embodiment and also has the role of adjusting the elution of phosphorus from the marine fertilizer, and commercially available magnesium oxide can be used. Magnesium oxide may be added in powder form, or may be dissolved in water and added as necessary.

The amount of magnesium oxide used is equivalent to 1 to 4 parts by weight, assuming that the amount of fermented chicken manure used is 12 parts by weight. Adding less than 1 part by weight of magnesium oxide is not preferred because it will cause a problem of insufficient hardness. Adding more than 4 parts by weight is also not preferred because it will cause a problem of excessive suppression of phosphoric acid elution. By using 1 to 4 parts by weight of magnesium oxide, an optimal supply of phosphoric acid can be achieved.

In addition, other auxiliary materials may be added to the marine fertilizer material according to this embodiment. Examples of such auxiliary materials include leaf mold and culture soil. The amount and components of these auxiliary materials can be appropriately selected within a range that maintains a balance of dissolution of nitrogen (N), phosphorus (P), potassium (K), iron, etc. that does not impede the achievement of the object of the present invention.

Then, 2 to 6 parts by weight of granular iron and 1 to 4 parts by weight of magnesium oxide are mixed with 12 parts by weight of the fermented chicken manure, and auxiliary ingredients are added as necessary to adjust the moisture content of the mixture to 45 to 60% by weight. In other words, water is added to the mixture in an amount that will result in a moisture content of 45 to 60% by weight.

This moisture-adjusted mixture can be subjected to compression molding in a specified compression molding machine to obtain the marine fertilizer material according to this embodiment.

In other words, it is possible to provide a marine fertilizer that is a highly sustainable organic fertilizer whose main component is derived from chicken manure, and that can dissolve nutrients suitable for the growth of algae that serve as food for herbivorous bivalve mollusks, for example, N/P = 10-30 and Fe/P = 0.001-0.1, and can also effectively increase the growth and survival of bivalve mollusks.

The marine fertilizer material is not particularly limited in shape as long as it is compressed and molded, but it can have a pellet-like or columnar appearance, for example. The size is also not limited, and by making it into a columnar shape with a height of 10 to 30 cm and a width of 15 to 30 cm, it can become a marine fertilizer material with excellent durability. In this case, the area/volume ratio can be approximately 0.1 to 0.9, or more specifically, approximately 0.2 to 0.5. The compression molding pressure is preferably 300 kgf or more per 0.4 square meters, and can be, for example, 0.5 to 1.0 ton per 0.4 square meters.

The fermented chicken manure is preferably produced through a process of preparing a fermented mixture, a process of promoting fermentation, a process of turning over, a process of repeating, and a process of producing fermented chicken manure.

The process for preparing the fermented mixture involves adding a fermentation liquid of a chicken manure fermenting microorganism to a mixture of chicken manure and a moisture regulator with a lower moisture content than the chicken manure to adjust the moisture content to within the range of 60±5%. As the moisture content regulator, for example, the fermented chicken manure obtained through each of the above processes or other dried sawdust can be used.

The process of promoting fermentation is carried out by piling up the resulting fermented mixture. Piling can be carried out, for example, in a roofed fermentation yard surrounded on three sides by concrete or the like, and although it depends on the amount of fermentation, the height can be approximately 1.8 to 2.0 m.

The turning process is a process in which the fermented mixture is turned when its temperature reaches 70°C or higher, before it reaches 80°C, and the fermented mixture is piled up again. By turning the mixture, oxygen can be supplied to the piled up fermented mixture while maintaining the optimum temperature range for the lactic acid bacteria and yeast that perform the fermentation.

The repeating process is a process in which the above-mentioned turning process is repeated until the moisture content of the fermented mixture falls below 35% and the temperature does not rise above 45°C. Note that this is only a rough guideline as it varies depending on the season and temperature, but the turning process, including this repeating process, is generally carried out about 3 to 5 times before the next fermented chicken manure production process is carried out.

The fermented chicken manure production process is a process in which the fermented mixture obtained through the repeating process is subjected to a further additional fermentation process as necessary to produce fermented chicken manure. That is, the fermented mixture obtained through this repeating process may be directly used as fermented chicken manure in this process, or it may be used as fermented chicken manure after being subjected to a further additional fermentation process.

As an additional fermentation step that may be performed as necessary in this process, the fermented mixture that has gone through the repeated process is piled up high (for example, 2m or more) so that it is leaned against a wall, and fermentation is carried out while compressing the lower part under its own weight and turning it over once or twice a month.

In this additional fermentation process, it is preferable to ferment and mature the manure while turning it over until the moisture content is 20% or less, the nitrogen content is 2.8% or more, the phosphoric acid content is 3.8% or more, and the potassium content is 3.0% or more, to produce fermented chicken manure.

The aforementioned chicken manure fermentation microorganism fermentation liquid is a liquid that is fermented by microorganisms (hereinafter also referred to as chicken manure fermentation microorganisms) that can improve the bottom sediment environment where excess organic matter exists in the target area for bottom sediment environment improvement, such as areas that have become sludge-like, and contains metabolic products of the chicken manure fermentation microorganisms. In the present application, however, it is characterized in that it is used to function as a starter for forming a bacterial flora that ferments and matures chicken manure in the fermentation mixture.

The type of chicken manure fermentation microorganism is not particularly limited, but for example, microorganisms selected from the microbial population contained in brackish water collected from the brackish water area described below using a screening method described below, in particular a bacterial flora containing a large amount of halophilic (salt-tolerant) yeast, are used.

In other words, the chicken manure fermentation microorganism fermentation liquid is not particularly limited as long as it contains fermentation metabolic products produced by the fermentation of the chicken manure fermentation microorganisms described above and is a liquid in which the bacterial activity and amount are increased, but for example, a liquid produced through a predetermined settling step, container placement step, microbial selection step, solid-liquid separation step, first fermentation step, and second fermentation step described below can be used. By going through these steps, the chicken manure is excellent in fermentation and maturation due to the symbiosis of brackish water-derived halophilic (salt-tolerant) yeast and other microorganisms derived from the raw materials (e.g., lactic acid bacteria), and contributes to the production of nutritional components suitable for algae growth.

The settling step is a step of mixing materials (hereinafter collectively referred to as extract extraction materials) that are the raw materials for extracting the extract contained in the defective fermentation inhibitor with brackish water containing at least halophilic (salt-tolerant) yeast, and dissolving the extract into the brackish water while standing still. This is a step of standing still for a predetermined period of time for a mixture of 0.6 parts by weight of dried stevia stem powder, 0.6 parts by weight of rice bran powder, 0.6 parts by weight of dried soybean pulp powder, and 11 to 13 parts by weight of brackish water containing at least halophilic (salt-tolerant) yeast. In this settling step, predetermined amounts of the extract extraction materials and brackish water are mixed and left to stand for a predetermined period of time, for example, at room temperature. The time required for standing can be, for example, 15 to 20 days.

The container placement process is a process in which the mixed liquid that has been through the settling process is placed in a specified container, and a weak sterilization area is formed in the placed mixed liquid that is 10 cm or more from any position on the outer surface of the container shape of the mixed liquid, and 17 cm or less from at least any position on the outer surface, so that complete sterilization does not occur when the mixed liquid is heated in the microorganism selection process described below.

The microorganism selection process is a process in which a specified container containing the mixed liquid after the container placement process is placed in a heating space, the heating space is heated from room temperature and normal pressure to 150-160°C at about 2.5 atmospheres over 45-60 minutes, the state of 150-160°C at about 2.5 atmospheres is maintained for 1-3 minutes to perform the first heating process, the heating space is then cooled to 115-125°C at about 2 atmospheres over 3-5 minutes, the state of 115-125°C at about 2 atmospheres is maintained for 20-40 minutes to perform the second heating process, and the heating space is further cooled to room temperature and normal pressure over 24-30 hours to perform the cooling process, thereby leaving the microorganisms selected by heating in the mixed liquid.

The solid-liquid separation process is a process for obtaining a microorganism-containing liquid by performing solid-liquid separation on the mixed liquid that has been through the microorganism selection process using a means that allows at least the microorganisms to migrate to the liquid phase. Solid-liquid separation does not necessarily require complete removal of solids, but is merely an idea of roughly removing solids and improving fluidity while transferring the selected microorganisms to the liquid phase. Such solid-liquid separation can be performed, for example, by placing the mixed liquid in a cloth bag or the like and using the spin-drying function of a washing machine. Alternatively, solid-liquid separation can be performed by applying a centrifugal force sufficient to leave the microorganisms in the liquid phase using a general solid-liquid separation device, or the mixed liquid can be placed in a cloth bag and squeezed to obtain the liquid phase.

The first fermentation process is a process in which a sugar source is added to the obtained microorganism-containing liquid and fermented at room temperature and pressure for a predetermined time, so that the pH of the microorganism-containing liquid is 4.5 or less and the redox potential is -100 mV or less.

The second fermentation process is a process in which a stevia stem matured liquid is added to the microorganism-containing liquid that has been through the first fermentation process, and fermented until the pH is 3.1 or less to produce a defective fermentation inhibitor. The amount of stevia stem matured liquid added to the microorganism-containing liquid can be about 0.38 to 0.4 parts by weight per 0.38 parts by weight of the microorganism-containing liquid.

Here, the stevia stem matured liquid used in this second fermentation step can be a fermented liquid obtained by soaking stevia stems in water or the like to extract the extract while fermenting with microorganisms derived from stevia stems (hereinafter also referred to as a simple stevia stem matured liquid).

However, it is more preferable to prepare the stevia stem matured liquid through a stevia stem dispersion preparation process, a stevia stem dispersion container placement process, a stevia stem-derived microorganism selection process, a stevia stem extract preparation process, an extract concentration process, and a maturation process.

The stevia stem dispersion preparation process is a process in which water is added to dried stevia stem powder to prepare a stevia stem dispersion. Specifically, the process is carried out by adding approximately 10 parts by weight ± 2 parts by weight of water to 1 part by weight of dried stevia stem powder.

The stevia stem dispersion container placement process is a process in which the stevia stem dispersion is placed in a container capable of forming a weak sterilization region so that complete sterilization does not occur when heated in the stevia stem-derived microorganism selection process described below, in a manner similar to the container placement process described above.

The weakly sterilized region in this stevia stem dispersion container placement process is an internal region that is 10 cm or more from any position on the outer surface and 17 cm or less from at least any position on the outer surface of the container in which the stevia stem dispersion is placed. More preferably, a container is used that is capable of forming a weakly sterilized region without forming a non-selected region that is more than 17 cm from any position on the outer surface.

The stevia stem-derived microorganism selection process, like the above-mentioned microorganism selection process, is a process in which a stevia stem dispersion is heated to select microorganisms derived from stevia stems, and more specifically, it is composed of a first stevia stem heating process and a second stevia stem heating process.

In the first stevia stem heating process, a specified container that contains stevia stem dispersion after the stevia stem dispersion container placement process is placed in a heating space, and the heating space is heated from room temperature and pressure to 150-160°C at approximately 2.5 atmospheres over a period of 30-40 minutes, and the state of 150-160°C at approximately 2.5 atmospheres is maintained for 1-3 minutes.

The second stevia stalk heating process follows the first stevia stalk heating process, in which the heating space is cooled to 115-125°C at approximately 2 atmospheres over a period of 3-5 minutes, and then maintained at 115-125°C at approximately 2 atmospheres for 20-40 minutes.

After the first stevia stem heating process and the second stevia stem heating process, the stevia stem dispersion is cooled to 85-95°C, allowing the heat-selected microorganisms derived from dried stevia stem to remain in the stevia stem dispersion.

The stevia stem extract preparation process is a process in which a liquid phase is obtained by solid-liquid separation from the stevia stem dispersion liquid that has been subjected to the stevia stem-derived microorganism selection process.

Specifically, following the second stevia stem heating step described above, the stevia stem dispersion liquid is cooled to 85-95°C and then subjected to solid-liquid separation using a means that allows at least the microorganisms to migrate to the liquid phase, and the liquid phase is obtained as a stevia stem extract. This stevia stem extract liquid has a Brix value of 2.0-4.0 and contains microorganisms derived from stevia stem.

The extract concentration process is a process in which the stevia stem extract is heated and boiled down to a specified concentration to obtain a stevia stem concentrate. Specifically, the stevia stem extract is heated and boiled down, and then concentrated so that when cooled to room temperature, the Brix value is 4.0 to 7.0, the pH is 6.0 or less, and the ORP is 10 to 99 mV.

The maturation process involves maturing the stevia stem concentrate at room temperature while fermenting to obtain a stevia stem matured liquid with a pH of 5.0 or less and an ORP of -100mV or less.

In this way, by going through the stevia stem dispersion preparation process, the stevia stem dispersion container placement process, the stevia stem-derived microorganism selection process, the stevia stem extract preparation process, the extract concentration process, and the maturation process, it is possible to obtain a stevia stem maturation liquid suitable for producing a defective fermentation inhibitor.

Furthermore, if the liquid produced through the above-mentioned settling process, container placement process, microorganism selection process, solid-liquid separation process, first fermentation process, and second fermentation process is used as a chicken manure fermentation microorganism fermentation liquid, the fermentation of chicken manure can be carried out more reliably.

Although this chicken manure fermentation microorganism fermentation liquid is obtained by the method described above, this does not limit the manufacturing method of the chicken manure fermentation microorganism fermentation liquid, but specifies the manufacturing method of the chicken manure fermentation microorganism fermentation liquid by the settling step, container placement step, microorganism selection step, solid-liquid separation step, first fermentation step, and second fermentation step.

In general, natural products such as plant powders, rice bran, soybean pulp, and brackish water contain various components and microorganisms in complex states and ratios, just like other natural products. In the above-mentioned screening environment, it is believed that certain microorganisms can be selected that can utilize components that other microorganisms cannot utilize, or that can find value in the metabolic products of certain microorganisms, and furthermore, that the presence of the components that make up these raw materials can function as a chicken manure fermentation microbial fermentation liquid that can perform suitable fermentation.

However, when taking into account the fermentation metabolism of microorganisms during the manufacturing process and their products, it is impossible or almost impractical to directly identify the individual bacteria that make up the microbial flora that causes this type of bottom sediment improvement, quantify the number of bacteria, or specify the type and concentration of components derived from each raw material using specific parameters.

Therefore, the chicken manure fermentation microorganism fermentation liquid was specified by the manufacturing method because the chicken manure fermentation microorganism fermentation liquid can only be specified by the manufacturing method. The same applies to the chicken manure fermentation microorganism fermentation liquid as a component of the marine fertilizer material according to this embodiment.

The same is true for the fermented chicken manure, which is the raw material for the marine fertilizer according to this embodiment. It has been described as being produced through the steps of preparing a fermented mixture, promoting fermentation, turning, repeating, and producing fermented chicken manure. However, this does not limit the method for producing fermented chicken manure, or the method for producing marine fertilizer. The fermented chicken manure is specified by the method for producing the steps of preparing a fermented mixture, promoting fermentation, turning, repeating, and producing fermented chicken manure. Identifying the individual bacteria that make up the microflora in the fermented chicken manure, quantifying the number of bacteria, and specifying the types and concentrations of components derived from each raw material are impossible or almost impractical to directly specify using predetermined parameters, etc., taking into account the fermentation metabolism by microorganisms during the production process and their products. In other words, the fermented chicken manure is specified by the production method because it can only be specified by the production method. However, this does not prevent the applicant from intentionally interpreting the invention in a way that limits some or all of the manufacturing method for the chicken manure fermentation microorganism fermentation liquid, fermented chicken manure, etc., when granting the patent for this application.

The above explanation of each component of the marine fertilization material according to this embodiment can be interpreted as an explanation of each component of the manufacturing method of the marine fertilization material according to this embodiment.

In other words, in the manufacturing method of marine fertilizer according to this embodiment, a mixture of 12 parts by weight of fermented chicken manure, 2 to 6 parts by weight of granular iron, 1 to 4 parts by weight of magnesium oxide, and an amount of water that will result in a moisture content of the marine fertilizer of 45 to 60% by weight is compressed and molded into a column shape 10 to 30 cm in height and 15 to 30 cm in width, and a marine fertilizer can be manufactured that is a highly sustainable organic fertilizer that is mainly composed of chicken manure-derived materials, can dissolve nutrients suitable for the growth of algae that serves as food for herbivorous bivalve mollusks, and can effectively increase the growth and survival of bivalve mollusks.

The present application also provides a method for installing the marine fertilization material according to this embodiment. The installation method of the present application is a method for installing the marine fertilization material or the marine fertilization material manufactured by the manufacturing method of the marine fertilization material described above, and includes a step of forming a hole of approximately the same height as the marine fertilization material in the tidal flat and installing the material, and a step of placing the marine fertilization material in the formed hole and then covering the top of the marine fertilization material with a small amount of sand.

This configuration makes it possible to prevent adhesion of large algae, in particular, to the surface of the marine fertilization material when it is placed underwater, and to facilitate the elution of the constituent components of the fertilization material.

This marine fertilizer is easy to install, is a highly sustainable organic fertilizer, and uses chicken manure as its main component, and is effective as a marine fertilizer that can dissolve nutrients suitable for the growth of algae that serve as food for herbivorous bivalve mollusks.

The marine fertilizer material, manufacturing method, and installation method according to this embodiment will be further explained below, including the manufacturing process and test results.

[1. Screening of chicken manure fermentation microorganisms]
In a 20L stainless steel container (diameter 32cm, height 38cm), 0.85kg of dried stevia stem powder, 0.85kg of rice bran powder, and 0.85kg of dried soybean pulp powder were added, and 17kg of brackish water collected from the Abu River estuary in Yamaguchi Prefecture (area with a salinity of about 0.8-1.0%) was added, stirred, and mixed to prepare several batches, which were then left to stand overnight (about 15-17 hours) at room temperature (standing process). A microbial test of the mixture that had been left to stand confirmed the presence of at least Lactobacillus buchneri among several microorganisms detected.

In addition, a separate microbial test was conducted on the collected brackish water, confirming that it contained salt-tolerant yeasts at a concentration of 150 cfu/ml.

Next, 20 L of the mixture that had undergone the standing process was placed in a lidded stainless steel container P1 (cylindrical with an inner diameter of 28 cm and a height of 33 cm) with a capacity of approximately 20.31 L, and a weak sterilization area was formed in the container (container placement process). Similarly, 20.41 L of the mixture that had undergone the standing process was placed in a lidded stainless steel container Q1 (cylindrical with an inner diameter of 20 cm and a height of 67 cm) with a capacity of approximately 21.04 L, and the shape of the mixture placed in the stainless steel container Q1 was set to a cylindrical shape with a diameter of 20 cm and a height of 65 cm, forming a weak sterilization area. In addition, 30.85 L of the mixture that had undergone the standing process was placed in a lidded stainless steel container R1 (cylindrical with an inner diameter of 34 cm and a height of 36 cm) with a capacity of approximately 32.67 L, and the shape of the mixture placed in the stainless steel container R1 was set to a cylindrical shape with a diameter of 34 cm and a height of 34 cm, forming a weak sterilization area.

Next, the mixed liquid was placed in each of the stainless steel containers P1, Q1, and R1 in a pressure cooker, and the temperature was raised to 150-160°C at approximately 2.5 atmospheres over 45-60 minutes, and the state of 150-160°C at approximately 2.5 atmospheres was maintained for 1-3 minutes (first heating step).

Next, the temperature was lowered to 115-125°C at approximately 2 atm over a period of 3-5 minutes, and the temperature was maintained at 115-125°C at approximately 2 atm for 20-40 minutes (second heating step).

Next, the heating switch of the pressure cooker was turned off, and the temperature inside the pressure cooker was allowed to drop to room temperature and pressure over a period of 24 to 30 hours (temperature drop process).

Then, the lid of the pressure cooker was opened, and a mixture was obtained in each of the stainless steel containers P1, Q1, and R1, in which the chicken manure fermentation microorganisms had been screened. As a result of the microbial testing of this mixture, the presence of at least Lactobacillus buchneri was confirmed among the several microorganisms detected.

2. Preparation of stevia stem ripening liquid
First, 10±2 kg of water was added to 1 kg of dried stevia stem powder in a specified container and mixed thoroughly to prepare a stevia stem dispersion (stevia stem dispersion preparation step). Note that this stevia stem dispersion was prepared in several batches.

Next, 12 L of the stevia stem dispersion liquid prepared in the stevia stem dispersion liquid preparation process was placed in a lidded stainless steel container P2 (inner diameter 25 cm, height 25 cm) with a capacity of approximately 12.27 L, and a weak sterilization area was formed in the stevia stem dispersion liquid placed in the container (stevia stem dispersion liquid container placement process). Similarly, 12 L of the stevia stem dispersion liquid prepared in the stevia stem dispersion liquid preparation process was placed in a lidded stainless steel container Q1 (cylindrical shape with an inner diameter of 20 cm and a height of 67 cm) with a capacity of approximately 21.04 L, and the shape of the stevia stem dispersion liquid placed in the stainless steel container Q1 was made cylindrical with a diameter of 20 cm and a height of 38 cm, forming a weak sterilization area. In addition, 30.85 L of the stevia stem dispersion liquid prepared in the stevia stem dispersion liquid preparation process was placed in a lidded stainless steel container R1 (cylindrical with an inner diameter of 34 cm and a height of 36 cm) with a capacity of approximately 32.67 L, and the shape of the stevia stem dispersion liquid contained in the stainless steel container R1 was made cylindrical with a diameter of 34 cm and a height of 34 cm to form a weak sterilization area.

Next, the stevia stem dispersion liquid was placed in the stainless steel containers P2, Q1, and R1 in a pressure cooker and heated to 150-160°C at approximately 2.5 atmospheres over 30-40 minutes, and then maintained at 150-160°C at approximately 2.5 atmospheres for 1-3 minutes (first stevia stem heating process).

Next, the temperature was lowered to 115-125°C at approximately 2 atm over a period of 3-5 minutes, and the temperature was maintained at 115-125°C at approximately 2 atm for 20-40 minutes (second stevia stalk heating process).

Next, the heating of the pressure cooker was stopped, and when the inside of the pressure cooker reached approximately normal pressure (a pressure at which the lid could be opened) and the temperature reached approximately 85-95°C, the stainless steel containers P2, Q1, and R1 containing the stevia stem dispersion were removed from the pressure cooker, and the stevia stem dispersion was transferred into a cotton cloth bag.

The cloth bag containing the stevia stem dispersion was placed in a dehydrator while still hot, and solid-liquid separation was carried out to obtain a stevia stem extract (stevia stem extract preparation process). This stevia stem extract had a Brix value of 2.0 to 4.0, and a separate microbial test confirmed that the genus Lactobacillus, a microorganism derived from stevia stem, was contained in all of the stainless steel containers P2, Q1, and R1.

Next, the obtained stevia stem extract was placed in a heat-resistant container and placed on a gas stove for about 4 to 5 hours to prepare a stevia stem concentrate (extract concentration process). After that, the heating was stopped and the stevia stem concentrate was left to cool to room temperature. A physical and chemical test was then performed on the stevia stem concentrate, which confirmed that the Brix value was 4.0 to 7.0, the pH was 6.0 or less, and the ORP was 10 to 99 mV.

Next, the obtained stevia stem concentrate was placed in a stainless steel fermentation and maturation can (12 L capacity) with a hook and left to stand at room temperature for maturation (maturation process). During maturation, gas accompanied by a fermentation odor was generated from each of the stevia stem concentrates in the stainless steel containers P2, Q1, and R1, and it was confirmed that the fermentation occurred to approximately the same extent regardless of the difference in the container shape of the stainless steel containers P2, Q1, and R1.

The stevia stem concentrate was considered to be matured stevia stem liquid when its pH was below 5.0 and its ORP was below -100mV during maturation. Even at this point, no differences such as abnormal fermentation due to the shape of the stainless steel containers P2, Q1, and R1 were observed, so in subsequent experiments, all of the matured stevia stem liquids were treated as the same.

3. Preparation of chicken manure fermentation microbial fermentation liquid
The mixed liquids in the stainless steel containers P1, Q1, and R1, which had been subjected to the temperature-lowering process and screening of poultry manure fermentation microorganisms as described above in [1. Screening of poultry manure fermentation microorganisms], were each placed separately in cotton cloth bags, and these cloth bags were subjected to a dehydrator to perform solid-liquid separation to obtain a microorganism-containing liquid (solid-liquid separation process).

Next, about 9 kg of the solid-liquid separated microorganism-containing liquid was placed in stainless steel containers P1, Q1, and R1, each of which was placed in a fermentation/aging can (12 L capacity) with a hook, and 0.1 kg of maple syrup was added to each as a sugar source, stirred uniformly, and left to stand at room temperature and pressure for approximately 20 to 30 days to allow fermentation to occur (first fermentation process).

In the initial stage of this first fermentation process, a supernatant is formed on the surface of the microorganism-containing liquid, but based on the inventors' experience, this is removed every few days to slow down the fermentation. In addition, after this initial stage, the microorganism-containing liquid begins to foam like beer, confirming that fermentation is taking place by the microorganisms.

The first fermentation process was terminated when the pH of the microorganism-containing liquid was 4.5 or less and the redox potential was -100 mV or less. At this point, no differences such as abnormal fermentation due to differences in the container shapes were observed between the stainless steel containers P1, Q1, and R1.

Next, the stevia stem matured liquid obtained in the above [2. Preparation of stevia stem matured liquid] was added to the microorganism-containing liquid that had been through the first fermentation process, and the mixture was stirred uniformly and left to stand at room temperature and pressure for approximately 20 to 25 days to allow fermentation to occur (second fermentation process).

Specifically, 0.75 kg of the microorganism-containing liquid from stainless steel container P1, Q1, or R1 that had undergone the first fermentation step and 0.75 kg of stevia stalk aged liquid were placed in a 10 L secondary fermentation can, and water was added to bring the total weight to 10 kg, followed by uniform stirring to prepare the fermented liquid to be subjected to the second fermentation step. If necessary, about 0.75 kg of a sugar source may be further added to the fermented liquid, for example, oligosaccharides, more preferably sugar beet sugar, may be added.

The second fermentation step was terminated when the pH reached 3.1 or less, and the resulting fermentation liquid was designated as a chicken manure fermentation microorganism fermentation liquid. At this stage, no differences such as abnormal fermentation due to the shape of the stainless steel containers P1, Q1, and R1 were observed, and all chicken manure fermentation microorganism fermentation liquids were treated as the same in the subsequent tests. The number of photosynthetic bacteria belonging to the genus Chromatium in the chicken manure fermentation microorganism fermentation liquid was 20 cfu/ml or less. The number of salt-tolerant yeasts was 1.2 x ¹⁰⁶ cfu/ml.

[4. Production of fermented chicken manure]
Five tons of diluted chicken manure fermentation microorganism fermentation liquid was added to 10 tons of chicken manure (about 40% moisture) discharged from a broiler chicken house, and the mixture was stirred and mixed to prepare 15 tons of a fermented mixture (about 60±5% moisture) of chicken manure to which chicken manure fermentation microorganism fermentation liquid was added (fermented mixture preparation process). Note that the chicken manure discharged from the broiler chicken house contains bedding, and the bedding acts as a moisture regulator to adjust the moisture content to 40% for the raw chicken manure with a moisture content of 70%. The diluted chicken manure fermentation microorganism fermentation liquid was prepared by diluting 25 kg of chicken manure fermentation microorganism fermentation liquid 200 times with water to prepare 5 tons.

Next, 15 tons of the prepared fermentation mixture was piled up to a height of approximately 1.8 m in a roofed concrete fermentation yard (fermentation promotion process), and when it was left in this state, a rise in the temperature of the fermentation mixture was observed within about 4 to 5 days.

The temperature of the piled fermented mixture was continued to be measured daily, and when the temperature of the fermented mixture reached 70°C or higher, it was turned over before it reached 80°C, and the turning process was carried out by piling the fermented mixture again.

This process of turning the mixture over and over was repeated about five times, lowering the moisture content of the fermented mixture to 35% or less, in this case to about 33% (repeated process). Furthermore, even when the moisture content of this fermented mixture was increased to about 40%, it was not heated to above 70°C, confirming that fermentation by microorganisms had progressed considerably.

Next, the fermented mixture that had undergone the repeating process was subjected to an additional fermentation process to produce fermented chicken manure.

The lees were piled high (e.g., just over 2m) against the concrete wall of the fermentation yard, compressed by their own weight, and turned over once or twice a month while they were aged until the moisture content was below 30%.

The fermented mixture continued to ferment, although the temperature rise was somewhat slow. When it was allowed to ferment until steam no longer came out even when it was turned over, the moisture content was below 20%, the nitrogen content was over 2.8%, the phosphoric acid content was over 3.8%, and the potassium content was over 3.0%, and this was called fermented chicken manure.

[5. Granular iron]
As the granular iron for the raw material for manufacturing the marine fertilizer according to this embodiment, steel slag obtained from a steel company was used. The steel slag had a granular shape with a diameter of about 3 to 10 mm.

[6. Magnesium oxide]
Commercially available powdered magnesium oxide was used as the magnesium oxide for the raw material for producing the marine fertilizer material according to this embodiment.

[7. Manufacturing of marine fertilizers (mixing and molding of raw materials)]
Next, the above-mentioned raw materials were mixed and pressure-molded to produce a marine fertilizer. Specifically, 12 parts by weight of fermented chicken manure, 4 parts by weight of granular iron, and 4 parts by weight of magnesium oxide were mixed, and water was added in an amount to make the water content of the mixture 45 to 60% by weight, and the mixture was mixed to prepare a moisture-adjusted mixture.

Next, the moisture-adjusted mixture was pressed three times using a press at a pressure of 500 kgf per 0.4 square meters to produce marine fertilizer material X according to this embodiment, which was densely molded into a cylindrical shape with a height of 20 cm and a diameter of 25 cm (area/volume ratio = 0.24).

[8. Test to confirm the amount of Fe eluted due to different amounts of steel slag]
Next, we confirmed how the amount of Fe elution changes depending on the amount of steel slag contained in the marine fertilizer.

Specifically, three types of marine fertilizers with different amounts of steel slag were manufactured according to the method described above in [7. Manufacturing marine fertilizers (mixing and molding of raw materials)]. The marine fertilizers manufactured were one with a ratio of fermented chicken manure:steel slag:magnesium oxide = 12 parts by weight:2 parts by weight:4 parts by weight (marine fertilizer Xa), one with a ratio of 12:4:4 (marine fertilizer Xb), and one with a ratio of 12:6:4 (marine fertilizer Xc). The ratio of steel slag to the total weight of the fermented chicken manure, steel slag, and magnesium oxide used as raw materials was 11% for marine fertilizer Xa, 20% for marine fertilizer Xb, and 27% for marine fertilizer Xc.

The experiment was carried out by placing marine fertilizer materials Xa to Xc, each 20 cm high and 25 cm in diameter, at the bottom of three tanks containing 100 L of seawater, and calculating the molar ratio of iron to phosphorus dissolved 3 and 7 days after the start of the experiment. The results are shown in Figure 1.

As can be seen from Figure 1, the marine fertilizer material, which contains 12 parts by weight of fermented chicken manure, steel slag, 4 parts by weight of magnesium oxide, and water in an amount that results in a moisture content of 45 to 60% by weight, can achieve an Fe/P ratio of 0.001 to 0.1 even when the proportion of steel slag is changed within the range of 2 to 6 parts by weight, demonstrating that it is possible to dissolve nutrients suitable for the growth of algae, which serves as food for herbivorous bivalve mollusks.

[9. Test to confirm eluted components due to differences in MgO content]
Next, we investigated the effect of different amounts of magnesium oxide on the elution rates of inorganic nitrogen and phosphoric acid. In the experiment, 2 g of marine fertilizer (molded into small grains the size of soybeans) was placed in a cylindrical semipermeable membrane tube, and an appropriate amount of sterilized filtered artificial seawater was added. The air was removed and both ends were blocked to create an elution sample.

Next, the eluted samples were suspended in a 500 mL container containing 400 mL of artificial seawater, and the percentage of inorganic nitrogen and phosphate eluted into the artificial seawater in the container was measured three and seven days after the start of the test.

The test involved seven types of marine fertilizer materials with different amounts of magnesium oxide added. Specifically, the seven materials were: fermented chicken manure:steel slag:magnesium oxide = 12 parts by weight:4 parts by weight:0 parts by weight (no additives) (marine fertilizer material Xd), a ratio of 12:4:1 (marine fertilizer material Xe), a ratio of 12:6:2 (marine fertilizer material Xf), a ratio of 12:6:3 (marine fertilizer material Xg), a ratio of 12:6:4 (marine fertilizer material Xh), a ratio of 12:6:6 (marine fertilizer material Xi), and a ratio of 12:6:10 (marine fertilizer material Xj). The percentage of magnesium oxide relative to the total weight of fermented chicken manure, steel slag, and magnesium oxide used as raw materials was 0% for marine fertilizer Xd, 5% for marine fertilizer Xe, 11% for marine fertilizer Xf, 15% for marine fertilizer Xg, 20% for marine fertilizer Xh, 27% for marine fertilizer Xi, and 38% for marine fertilizer Xj. The results are shown in Figure 2.

As can be seen from Figure 2, a marine fertilizer containing 12 parts by weight of fermented chicken manure, 4 parts by weight of steel slag, magnesium oxide, and water in an amount that results in a moisture content of 45 to 60% by weight can achieve an N/P ratio of 10 to 30 when the proportion of magnesium oxide is changed within the range of 1 to 4 parts by weight, demonstrating the ability to dissolve nutrients suitable for the growth of algae that serve as food for herbivorous bivalve mollusks.

[10. Testing to confirm eluted components in a large water tank]
The marine fertilizer material X made with the press was placed in a 100L tank, and the concentration of the eluted components was checked while seawater was poured over it. The experiment was carried out over a period of six months, and the concentration of the eluted components was checked approximately every two weeks.

As a result, the average N/P molar elution ratio during the period was 19.6, and the Fe/P molar elution ratio was 0.06. In other words, it was possible to achieve elution of Fe/P = 0.001-0.1 at N/P = 10-30, demonstrating that it is possible to elution of nutrients suitable for the growth of algae, which serves as food for herbivorous bivalve mollusks.

11. Field Testing
The marine fertilizer according to this embodiment was placed on the tidal flats of Urasaki, Onomichi City, and a field test was conducted to confirm the proliferation of the clam. Two plots measuring 3m x 10m were set up, one as a test area and the other as a control area.

Ten marine fertilization materials X according to this embodiment were installed in the test area. Each marine fertilization material X was installed through a process of forming a hole in the tidal flat with a height equivalent to that of the marine fertilization material X, for example, a hole of about 10 to 30 cm, and placing the marine fertilization material X in the hole formed in the process, and then burying the marine fertilization material X so that its top surface was almost even with the sand surface, and covering the top of this marine fertilization material X with a small amount of sand.

In addition, 271 ^individual clams with an average shell length of approximately 26 mm were scattered in both the test and control areas. Figure 3 shows the change in average individual clam weight over time.

The weight of the clams (3.68±0.60g) sprayed in the control area changed to 5.18±0.91g after two months, 5.93±1.15g after four months, 6.31±1.21g after five months, and 6.73±1.44g after six months (at the end of the experiment). The survival rate of the clams at the end of the experiment was 78% of that at the time of spraying.

On the other hand, the weight of the clams scattered in the test area (same weight as in the control area) changed to 5.30±0.90g after two months, 6.63±1.14g after four months, 6.95±1.56g after five months, and 6.88±1.50g after six months (at the end of the test), showing a tendency for better fattening compared to the clams in the control area after spraying. In particular, from the fourth month onwards, a significant difference in individual weight was observed compared to the clams in the control area (t-test, p<0.05). Furthermore, the survival rate of the clams at the end of the test was 93% compared to the time of spraying, which was higher than the control area.

In addition, the concentrations of nutrients in the bottom mud in both the control and test areas showed a tendency for dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), and dissolved silicon (DSi) to be significantly higher in the test area. However, in terms of the timing of elution, DIN, DSi, etc. tended to be early, while DIP tended to be slightly delayed.

From these findings, it was shown that the marine fertilizer according to this embodiment is an organic fertilizer that has excellent durability over a period of five months, is made primarily from chicken manure, and is capable of dissolving nutrients suitable for the growth of algae that serves as food for herbivorous bivalve mollusks, making it a fertilizer that can effectively increase the growth and survival of bivalve mollusks.

As described above, the marine fertilizer according to this embodiment is made of a columnar compressed molded body containing 12 parts by weight of fermented chicken manure, 2 to 6 parts by weight of granular iron, 1 to 4 parts by weight of magnesium oxide, and an amount of water that makes the moisture content of the marine fertilizer described below 45 to 60% by weight. This makes it a highly sustainable organic fertilizer that is mainly made of chicken manure and can dissolve nutrients suitable for the growth of algae that serve as food for herbivorous bivalve mollusks, making it a fertilizer that can effectively increase the growth and survival of bivalve mollusks.

Finally, the above-mentioned explanations of each embodiment are merely examples of the present invention, and the present invention is not limited to the above-mentioned embodiments. Therefore, even if the embodiment is different from the above-mentioned embodiments, various modifications can be made depending on the design, etc., as long as they do not deviate from the technical concept of the present invention.

Claims (6)

A marine fertilizer material that is made of a compressed molded body of a mixed material (excluding those that contain an amount of cement that is sufficient to solidify the entire mixed material) containing 12 parts by weight of fermented chicken manure, 2 to 6 parts by weight of granular iron, 1 to 4 parts by weight of magnesium oxide, and an amount of water that makes the moisture content of the marine fertilizer material described below 45 to 60% by weight , and is configured to be soluble in seawater at a ratio of N/P = 10 to 30 and Fe/P = 0.001 to 0.1. A method for producing a marine fertilizer material, comprising compressing and molding a mixture of 12 parts by weight of fermented chicken manure, 2 to 6 parts by weight of granular iron, 1 to 4 parts by weight of magnesium oxide, and an amount of water such that the moisture content of the marine fertilizer material described below is 45 to 60% by weight (excluding mixtures containing an amount of cement sufficient to solidify the entire mixture), and making the mixture soluble in seawater at a ratio of N/P = 10 to 30 and Fe/P = 0.001 to 0.1. The method for manufacturing a marine fertilizer material according to claim 2, characterized in that the mixed material contains leaf mold and/or culture soil as auxiliary raw materials within a range in which the balance of the elution is maintained. The fermented chicken manure is
A step of preparing a fermented mixture by adding a fermentation liquid of a chicken manure fermenting microorganism to a mixture of chicken manure and a moisture adjusting material having a lower moisture content than the chicken manure to adjust the moisture content to 60±5%;
piling the resulting fermented mixture to facilitate fermentation;
A turning step in which, when the temperature of the fermented mixture reaches 70°C or higher, the mixture is turned over before it reaches 80°C and the fermented mixture is piled up again;
a repeating step of repeating the turning step until the moisture content becomes 35% or less and the temperature does not rise to 45° C. or more;
A fermented chicken manure production process in which the fermented mixture that has been subjected to the repeating process is subjected to a further additional fermentation process as necessary to produce fermented chicken manure;
The method for producing a marine fertilizer material according to claim 2, characterized in that the material is produced through the steps of: The chicken manure fermentation microorganism fermentation liquid is
A step of allowing a mixture of 0.6 parts by weight of dried stevia stem powder, 0.6 parts by weight of rice bran powder, 0.6 parts by weight of dried soybean pulp powder, and 11 to 13 parts by weight of brackish water containing at least a salt-tolerant yeast to stand for a predetermined period of time;
A container containing step of containing the mixed liquid having been subjected to the standing step in a predetermined container and forming a weak sterilization region in the contained mixed liquid that is 10 cm or more from any position on the outer surface of the container shape of the mixed liquid and 17 cm or less from at least any position on the outer surface;
a microorganism selection process in which the predetermined container containing the mixed liquid after the container placement process is placed in a heating space, the heating space is heated from room temperature and normal pressure to 150-160°C at about 2.5 atmospheres over a period of 45-60 minutes, the state of 150-160°C at about 2.5 atmospheres is maintained for 1-3 minutes, the heating space is then cooled to 115-125°C at about 2 atmospheres over a period of 3-5 minutes, the state of 115-125°C at about 2 atmospheres is maintained for 20-40 minutes, and the heating space is further cooled to room temperature and normal pressure over a period of 24-30 hours, thereby allowing the microorganisms selected by heating to remain in the mixed liquid;
a solid-liquid separation step of obtaining a microorganism-containing liquid by subjecting the mixed liquid having been subjected to the microorganism selection step to solid-liquid separation using a means capable of transferring at least the microorganism to a liquid phase;
a first fermentation step in which a sugar source is added to the obtained microorganism-containing liquid and fermented at room temperature and normal pressure for a predetermined time to adjust the pH of the microorganism-containing liquid to 4.5 or less and the redox potential to -100 mV or less;
The method for producing a marine fertilizer according to claim 4, characterized in that the fermented liquid is obtained by adding a matured liquid of stevia stem to the microorganism-containing liquid that has been subjected to the first fermentation step, and fermenting the liquid until the pH becomes 3.1 or less to obtain a defective fermentation inhibitor. A method for installing a sea area fertilizer material manufactured by the method for manufacturing a sea area fertilizer material according to claim 1 or any one of claims 2 to 5 ,
A step of forming and installing a hole in the tidal flats at a height equivalent to that of the marine fertilizer material;
A step of placing a sea area fertilizer in the formed hole and then covering the top of the sea area fertilizer with a small amount of sand;
A method for installing a marine fertilization material, comprising the steps of:

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