KR20110021676A - Agent for preventing germination of aquatic plants - Google Patents

Abstract

PURPOSE: An agent for preventing germination of aqueous plants is provided to prevent germination without curing bottom clay. CONSTITUTION: An agent for preventing germination of aqueous plants in bottom clay contains magnesium oxide powder. The magnesium oxide powder contains 80 mass% of particles having 1mm particle size. The exterior density of the magnesium oxide powder is 2.10 g/cm^3. The germination of aqueous plants is prevented by spraying the agent to the bottom clay.

Description

AGENT FOR PREVENTING GERMINATION OF AQUATIC PLANTS}

The present invention relates to a germination inhibitor of aquatic plants rooted in the bottom mud of freshwater bodies such as harvest plants, side plants and submerged plants, and a method for preventing germination of aquatic plants.

In freshwater waters such as rivers and lakes, aquatic plants absorb nutrients such as phosphorus and nitrogen in water and bottom mud, which causes the algae to be suppressed. have.

However, if aquatic plants thrive abnormally, the development of odor due to decay (bad effects on life), the navigational disturbance of the ship, the fishing obstacle (deterioration of the fishery environment), the deterioration of the lake bottom environment (mudification, oxygen deprivation) Many problems arise, namely, adverse effects on ecosystems.

The removal method of the aquatic plant which thrived in a fresh water body is a method of cutting off aquatic plants. However, this method requires a lot of effort and requires the treatment of cut off aquatic plants.

PTL 1 describes a method of curing the ground as a method of preventing the growth of weeds on the ground. In Patent Document 1, as a method of hardening the ground, a weed propagation preventing material containing magnesium oxide is supplied to the ground, and after mixing and mixing the weed propagation preventing material and the soil, the water is sprayed on the soil and mixed with the soil magnesium oxide It is described a method of reacting with water to cure.

Japanese Unexamined Patent Publication No. 2003-47388

The method of curing the ground described in Patent Document 1 is useful as a method of preventing ground weed propagation. However, since various organisms live in the ground mud in the freshwater, the bottom mud in the freshwater is hardened. May adversely affect the ecosystem.

It is therefore an object of the present invention to provide a method capable of preventing the germination of aquatic plants without curing the bottom mud of fresh water, and an anti-germination agent of aquatic plants useful for preventing germination of the aquatic plants.

The present inventors found that when magnesium oxide powder having a particle diameter of 1 mm or less is dispersed in the bottom mud of a freshwater water, germination of aquatic plants can be prevented without curing the bottom mud.

Accordingly, the present invention is directed to a germination inhibitor of aquatic plants rooted in the bottom mud of fresh water, containing magnesium oxide powder having a particle diameter of 1 mm or less.

Preferred embodiments of the anti-germination agent of the aquatic plant of the present invention are as follows.

(1) The magnesium oxide powder contains 80 mass% or more of particles having a particle diameter of 1 mm or less.

(2) Magnesium oxide powder contains 80 mass% or more of particle | grains whose particle diameter is 0.75 mm or less.

(3) Magnesium oxide powder shows an apparent density of 2.10 g / cm 3 or more.

(4) Magnesium oxide powder is a light magnesium oxide powder or an electrolytic magnesium oxide powder.

(5) Aquatic plants are plants of the Hydrocaryaceae family (also known as the Trapaceae family).

The present invention also relates to a method for preventing germination of aquatic plants rooted in the bottom mud of freshwater bodies such as harvest plants, foliar plants and submerged plants, which disperse the germination of the aquatic plants of the present invention in the bottom mud of freshwater bodies. .

By spreading the anti-germination agent of the aquatic plant of the present invention in the bottom mud of fresh water, the germination of aquatic plants, particularly dry and plant rooted in the bottom mud of the fresh water can be effectively prevented.

1 is a photograph taken from above of the transparent plastic case of Example 1. FIG.
2 is a photograph taken from above of the transparent plastic case of Comparative Example 1. FIG.

The germination inhibitor of the present invention includes a relatively fine magnesium oxide powder having a particle diameter of 1 mm or less. It is preferable that the average particle diameter of magnesium oxide powder is 0.75 mm or less, and it is more preferable to exist in the range of 0.03-0.5 mm. The apparent density (or bulk density) of magnesium oxide powder is preferably 2.10 g / cm 3 or more, more preferably in the range of 3.10 to 3.56 g / cm 3, still more preferably in the range of 3.10 to 3.50 g / cm 3 , Particularly preferably in the range of 3.15 to 3.30 g / cm 3. The apparent density of magnesium oxide powder can be measured by a gas phase substitution method based on Archimedes' principle.

The magnesium oxide powder used in the germination inhibitor of the present invention may contain coarse particles having a particle diameter larger than 1 mm. However, it is preferable that magnesium oxide powder contains 80 mass% or more of fine particles whose particle diameter is 1 mm or less, and it is especially preferable to contain 90 mass% or more. Furthermore, it is preferable that magnesium oxide powder contains 80 mass% or more of particle | grains whose particle diameter is 0.75 mm or less, and it is especially preferable to contain 90 mass% or more. Moreover, it is preferable to contain 80 mass% or more of particle | grains whose particle diameter is larger than 0.005 mm, and it is especially preferable to contain 90 mass% or more.

The magnesium oxide powder used in the germination inhibitor of the present invention is preferably a small magnesium oxide powder and an electrolytic magnesium oxide powder.

In the present invention, the small magnesium oxide powder is a magnesium oxide calcined product obtained by calcining magnesium compounds such as magnesium hydroxide and magnesium carbonate at a temperature of 900 ° C. or higher, preferably 1600 ° C. or higher, particularly preferably 1700 to 2100 ° C. It means what was manufactured by the method of adjusting particle size as it is, or after grind | pulverizing process, and by normal classification, such as a pole.

In the present invention, the molten magnesium oxide powder is magnesium oxide, or magnesium oxide molten solids obtained by melting magnesium compounds such as magnesium hydroxide and magnesium carbonate as they are, or after pulverizing, and then particle size by conventional classification, such as Refers to the manufacturing by the method of adjusting the.

Examples of magnesium hydroxide used as a raw material for producing light magnesium oxide powder and electrolytic magnesium oxide powder include magnesium hydroxide powder obtained by drying magnesium hydroxide precipitated by adding calcium hydroxide to seawater or bitter juice or brine containing magnesium salt. Can be mentioned. As an example of magnesium carbonate, natural magnesite is mentioned. Moreover, as an example of magnesium oxide used as a raw material of manufacture of an electrolytic magnesium oxide powder, a light magnesium oxide powder, a light magnesium oxide powder, and a magnesia clinker are mentioned.

The magnesium oxide fired article and the magnesium oxide molten solids preferably have a bulk density of 2.10 g / cm 3 or more, more preferably in the range of 3.10 to 3.50 g / cm 3, particularly in the range of 3.10 to 3.30 g / cm 3 desirable. Incidentally, the bulk density of the magnesium oxide calcined product and the magnesium oxide molten solid can be measured by the Archimedes method using kerosine in the medium.

By spreading the anti-germination agents of the present invention to the bottom mud of freshwater bodies, harvest plants (e.g., reeds, buds, lotuses, strings, elders, lotuses), deciduous plants (e.g. dry, thorny lotuses, water lilies, Germination of aquatic plants rooted in the ground mud of freshwater bodies such as sputum) and submerged plants (eg, horses, black horses, ear scrubbers, horses, axles).

 The spreading amount of the germination inhibitor is preferably in the range of 0.1 to 10 kg, particularly preferably in the range of 0.5 to 5 kg, with respect to an area of 1 m 2 of the bottom mud. The spreading time of the germination inhibitor is preferably one week to three months before the start of the germination of aquatic plants.

There is no particular limitation on the method of dispersing the germination inhibitor. For example, the anti-germination agent may be dispersed in the water surface of the freshwater water in powder state, or may be injected into the water of the freshwater water in the dispersion state in which the anti-germination agent is dispersed in water.

Germination inhibitors scattered in freshwater bodies settle within freshwater bodies and quickly reach the surface of the bottom mud. Since the germination inhibitor (magnesium oxide powder) that reaches the surface of the bottom mud is a fine powder, it dissolves quickly in water and denatures the surrounding bottom mud to a weak alkali, while the dissolved magnesium ions are phosphorus compounds around the bottom mud. To form poorly soluble magnesium phosphate. Germination of aquatic plants is effectively suppressed by altering the bottom mud to weak alkalinity and further fixing the phosphorus compound around the bottom mud as poorly water-soluble magnesium phosphate.

Example

Example 1

The bottom mud and lake water of the dry lake were collected and placed in a transparent plastic case (18 cm x 30 cm x 23 cm in height) so that the bottom mud had a depth of about 3 cm and the lake had a depth of about 9 cm. Subsequently, 54 g of light magnesium oxide powder (particle diameter: 0.75 mm or less, appearance density: 3.23 g / cm 3) were dispersed so as to be uniformly deposited on the entire ground mud, and deposited Viii). 1, the photograph which image | photographed the transparent plastic case after hardening for three weeks from upper direction is shown. As shown in FIG. 1, even after 3 weeks elapsed, dryness did not occur. Moreover, the bottom mud was not hardened as a result of sticking the bottom mud after hardening for 3 weeks with the glass rod.

Comparative Example 1

Except not scattering magnesium oxide powder, it carried out similarly to Example 1, and placed bottom mud and lake water in the transparent plastic case, and stood still. The photograph which photographed the transparent plastic case after hardening for 3 weeks in FIG. 2 from upper direction is shown. As shown in FIG. 2, after hardening for three weeks, dryness was bleeding.

Claims (8)

An anti-germination agent of aquatic plants rooted in the bottom mud of freshwater, containing magnesium oxide powder having a particle diameter of 1 mm or less. The method of claim 1,
The germination inhibitor of the aquatic plant in which magnesium oxide powder contains 80 mass% or more of particle | grains whose particle diameter is 1 mm or less. The method of claim 1,
The germination inhibitor of the aquatic plant in which magnesium oxide powder contains 80 mass% or more of particle | grains whose particle diameter is 0.75 mm or less. The method of claim 1,
A germination inhibitor of aquatic plants in which magnesium oxide powder exhibits an apparent density of at least 2.10 g / cm 3. The method of claim 1,
A germination inhibitor of aquatic plants, wherein the magnesium oxide powder is a light magnesium oxide powder or an electrolytic magnesium oxide powder. The method of claim 1,
Germination inhibitors of aquatic plants whose aquatic plants are dry and planty. The germination prevention method of the aquatic plant rooted in the bottom mud of a fresh water body which disperse | distributes the germination inhibitor of the aquatic plant of any one of Claims 1-6 in the bottom mud of a fresh water body. The method of claim 7, wherein
The germination prevention method of the aquatic plant in which the dispersion amount of the germination inhibitor of an aquatic plant exists in the range of 0.1-10 kg with respect to the area of 1 m <2> of bottom mud.

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