JPH0662666A - Artificial water retaining soil structure - Google Patents

Abstract

PURPOSE:To obtain a soil structure suitable for various uses, capable of suppressing evaporation of water in soil. CONSTITUTION:An artificial water retaining soil structure has a hydrophobic layer composed of hydrophobic particles on soil containing a water retaining agent. The hydrophobic layer may exist through a soil layer containing no water retaining agent on soil containing the water retaining agent. A soil layer containing no water retaining agent may sometimes exist further on the hydrophobic layer composed of the hydrophobic particles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a newly improved artificial water-retaining soil structure, and more specifically, an artificial water-retaining soil structure capable of controlling mainly evaporation of water in the soil, a method for producing the same, and the like. The present invention relates to a method for suppressing water evaporation in soil, which comprises using water to suppress evaporation of water in soil.

The artificial water-retaining soil structure of the present invention is used in all applications where it is useful to suppress evaporation of water in soil. For example, various agriculture, gardening such as potted plants,
It is used for street trees and afforestation of parks, but its application is not limited and can be applied to all fields.

[0003]

[Related Technology] The ratio of deserts occupying the land of the world is currently about 3
It is around 0%, but the area continues to increase. There are various causes for this, but human production activities such as environmental pollution such as tree felling and acid rain, large intake of groundwater, abnormal weather that is thought to be caused by ozone layer depletion and carbon dioxide gas increase, etc. There are many things that are based on the environmentally destructive factors that accompany.

On the other hand, the world's population is increasing year by year, and in order to avoid future food crisis due to this population increase, it is necessary to prevent desertification of soil and to revive dead and dead soil. is there.

For the purpose of avoiding the food crisis, efforts have been made to improve the production efficiency by improving the crops themselves by using biotechnology in recent years. However, in order to improve the production efficiency of agricultural products, it is necessary to improve the soil on which the agricultural products are grown to a soil suitable for various agricultural products. However, conventionally, soil improvement such as tilling the soil surface or applying fertilizer was routinely performed, but the soil was constructed for the purpose of fundamentally improving the soil environment based on the soil structure. Attempts to artificially assemble the soil layers to fundamentally improve the so-called soil structure itself have not been made normally.

As described above, at present, it is necessary to improve the soil structure in order to make the environmental properties of the soil desirable for human beings at the global environmental level. Often determined by the water content. Therefore, it is first necessary to improve the soil structure so that the water content in the soil can be artificially controlled.

Conventionally, as means for controlling the water content in the soil, for example, the soil and the water-retaining polymer compound are mixed, or as disclosed in JP-A-1-319585.
Means have been proposed for treating the surface of soil with high molecular weight hydrogen siloxanes.

[0008]

DISCLOSURE OF THE INVENTION The present inventors have earnestly studied from the viewpoint of the above-mentioned global environmental level and the like, and as a result, surprisingly, a water retention agent is contained in the soil structure. It was surprisingly found that when a hydrophobic layer made of hydrophobic particles is provided on the upper layer of the soil, evaporation of water in the soil can be efficiently suppressed, and the present invention has been completed.

Further, in the present invention, a soil layer is further formed from sand or soil on the hydrophobic layer, and the hydrophobic layer is provided not in the soil surface but in the soil. In the area as well, the present invention has been completed by finding that the present invention can be more effectively utilized because the hydrophobic layer is protected in the soil.

That is, an object of the present invention is to provide an artificial water-retaining soil structure having a hydrophobic layer composed of hydrophobic particles on the soil containing a water-retaining agent, and controlling the water content in the soil by improving the soil structure, For example, in industrial fields such as various agricultural and horticultural fields, and eventually in environmental protection industries such as soil desertification prevention, desert greening, forest protection, etc., the above problems are solved by artificially improving the soil structure itself. It is a thing.

The present invention does not simply improve the surface of the soil as in the prior art, but provides a hydrophobic layer composed of hydrophobic particles on the upper layer of the soil containing the water retention agent in the structure of the stratum zone constituting the soil. This is an epoch-making invention that artificially improves the original soil environment of the soil by mainly suppressing the evaporation of water in the soil.

[0012]

[Means for Solving the Problems] That is, according to the present invention, as described in claim 1, an artificial water-retaining soil structure having a hydrophobic layer made of hydrophobic particles on a soil having a water-retaining agent. It provides the body.

Further, the present invention includes claim 2 of the claims.
As described above, there is provided an artificial water retention soil structure having a hydrophobic layer composed of hydrophobic particles on a soil having a water retention agent via a soil layer not containing the water retention agent.

Further, according to the present invention, as described in claim 3 of the appended claims, a soil layer containing no water retention agent is further provided on the hydrophobic layer comprising hydrophobic particles.
Alternatively, the artificial water retentive soil structure described in 2 is provided.

The present invention also provides, as described in claim 4 of the appended claims, a water-holding agent-free soil layer existing on a hydrophobic layer having a thickness of 10 to 100 mm or The artificial water retention soil structure according to claim 3, which is a soil layer made of soil.

Furthermore, according to the present invention, as described in claim 5, the hydrophobic layer is partially hydrophobic, inside the hydrophobic layer or through the hydrophobic layer. An artificial water-retaining soil structure according to any one of claims 1 to 4, which has a soil portion having no.

Further, according to the present invention, as described in claim 6 of the appended claims, the water retention agent is a polymer compound having water retention property according to any one of claims 1 to 5. An artificial water retention soil structure is provided.

Further, according to the present invention, as described in claim 7 of the claims, the particle diameter of the hydrophobic particles is 20.
The artificial water-retaining soil structure according to any one of claims 1 to 6, which has a diameter of 00 µm or less.

Further, according to the present invention, as described in claim 8 of the claims, the hydrophobic particles are sand and / or soil particles treated with a water repellent. The artificial water retention soil structure according to any one of items 1 to 7 is provided.

Furthermore, the present invention provides the artificial water-retaining soil structure according to claim 8, wherein the water repellent agent is a silicone-based or fluorine-based water repellent agent as described in claim 9 of the appended claims. It is provided.

Next, the present invention relates to claim 1 of the claims.
As described in 0, the artificial water retention soil structure according to any one of claims 1 to 9, wherein the ground is dug into a finite area and depth and artificially created in a space formed in the ground. A method for producing an artificial water retentive soil, which comprises burying a body and artificially forming a stratum structure having a hydrophobic layer composed of hydrophobic particles on the soil having a water retention agent in the soil. is there.

Furthermore, the present invention is characterized by using the artificial water-retaining soil structure according to any one of claims 1 to 9 as described in claim 11 of the claims. It is intended to provide a method for suppressing water evaporation in soil.

The present invention will be described in detail below. In the present invention, any water-retaining agent can be used as long as it has the property of increasing the effective water content of the soil by including it in the soil.

Examples thereof include water-retaining polymers such as PVA, MC and CMC, acrylic polymer water-absorbing polymers, beet moss, inorganic pearlite, montmorillonite and vermiculite.

The present invention provides an artificial water retaining soil structure in which a hydrophobic layer is provided on the soil containing such a water retaining agent. The term "on the soil" means that it is on the stratum containing the water retention agent, and the hydrophobic layer composed of hydrophobic particles is present above the direction of the ground surface.

The hydrophobic particles for forming the hydrophobic layer are
Any material may be used as long as it has a so-called hydrophobic property and is in the form of particles, and the material thereof may be inorganic or organic.

Hydrophobicity is a concept including so-called water repellency.

In the present invention, the artificial water retention soil structure means
The soil structure configured as described above is a soil block having a three-dimensional structure.

The hydrophobic layer of the present invention is essentially composed of hydrophobic particles, and even if particles having other properties are mixed, the hydrophobic property of the entire layer is not lost and the present invention Is the range.

For example, the present invention can be applied to a case where the hydrophobic layer has a soil portion partially having no hydrophobicity or penetrating the hydrophobic layer, but the entire layer has hydrophobicity. 2 is an embodiment of the artificial water retention soil structure. This is, for example,
When the artificial water retentive soil structure of the present invention is used for planting a plant, it may be effective to remove hydrophobicity only in a limited part of planting a plant on the soil surface, and as a specific means therefor. There are cases such as planting seedlings in paper pot cultivation.

Further, depending on the application, it is possible to mix particles having other useful properties with the hydrophobic particles constituting the hydrophobic layer within a range in which the hydrophobicity is not lost in the entire hydrophobic layer.

The present invention may also be an artificial water-retaining soil structure having a hydrophobic layer composed of hydrophobic particles on a soil having a water retaining agent via a soil layer not containing the water retaining agent. This is an embodiment of the artificial water retention soil structure in the case where the soil layer having the water retention agent is not in contact with the upper hydrophobic layer (direction of the soil surface).

Such an aspect of the present invention is determined according to each application. For example, when a plant is cultivated in the artificial water-retaining soil structure of the present invention, an optimum soil structure suitable for the individual properties of the plant may be adopted within the scope of the present invention.

Further, in the present invention, it is preferable that the water retention agent is a polymer compound having water retention property from the viewpoint of water retention and practicability. The polymer compound may be a natural polymer or a synthetic polymer.

Further, the polymer used is preferably a polymer having durability against enzymes such as cellnase. further,
Those that generate toxic substances by decomposition are not preferable, and those that do not destroy the soil environment used are preferable. In this respect, cellulose derivatives, gums, PVA and the like are preferable.

When the present invention is used especially in a desert area which is extremely dry, an artificial water-retaining soil structure containing a so-called water-absorbing polymer having a good water-retaining property and capable of absorbing several hundred times its own weight of water as a water-retaining agent. The body is preferred.

The particle system of the hydrophobic particles constituting the hydrophobic layer of the present invention is not particularly limited as long as the object of the present invention can be achieved, but preferably, it is easy to control the water content. The average particle diameter is preferably 2000 μm or less. Particularly preferably, it is 1000 μm or less.

In the present invention, as the hydrophobic particles, it is practical that the surface of the particles of sand or soil is treated with a water repellent, and these can be used alone or in combination. Treated water repellent sand is preferred.

[0039] Sand can be collected easily and in large quantities from beaches, dunes, deserts and the like on the coast. It is possible to use the soil that has been once fired and made into particles.

For example, if a large amount of sludge that has been fired into particles is used, sludge can be effectively used and sludge treatment can be performed at the same time. Further, when a plant is planted on the artificial water-retaining soil structure of the present invention, the hydrophobic layer preferably has an aggregate structure, so that it is also effective to use aggregated soil particles treated with polyvinyl alcohol or the like. In addition,
Sand is a concept that also includes fine gravel, and soil is a concept that also includes clay.

The water repellent used is not particularly limited as long as it is generally used as a water repellent, but silicone-based and fluorine-based ones are particularly preferable. Among them, silicone type is particularly preferable from the viewpoint of water repellency and economics.

As the silicone water repellent, for example, the following general formula can be used.

And a silicone compound represented by the following:
It is used as it is (without solvent), diluted with a solvent such as toluene, xylene, trichlene, or used as an emulsion type. Further, a curing catalyst such as dibutyltin dilaurate, dibutyltin diacetate, dioctyltin laurate, iron octate may be used.

[0043]

Embedded image R ¹ aR ² bSiOx [R ¹ is the same or different, unsubstituted or substituted monovalent hydrocarbon group; R ² is the same or different group selected from a hydrolyzable group, —OH or —H A and b are 0 ≦ a <4 and 0 ≦ b
A number represented by ≤4, 0 <a + b≤4; x = (4-a-b) / 2. ] For example, the general formula

In the formula, R ¹ is an alkyl group having 1 to 15 carbon atoms such as methyl, ethyl, propyl and decyl, an alkenyl group such as vinyl and allyl, an aryl group such as phenyl, a cycloalkyl group and CH ₃ CH ₂ It is a group in which a part or all of hydrogen atoms bonded to carbon atoms of the above groups such as CH ₂ — are substituted with a halogen atom or a cyano group. Also, R ² is
Hydrolyzable groups such as alkoxy groups, acyloxy groups, ketoxime groups, amino groups, aminoxy groups, amido groups, enoxy groups, alkenyloxy groups, halogen groups such as chlorine, -OR ³ (R ³ is Na or K), -OH, -H, etc.

Specific silicone compounds include, for example,

From [Chemical 2]

The following compounds represented by: or a partial hydrolyzate thereof are used.

Embedded image HO-Si (ONa) (CH ₃ )-[OSi (ONa) CH
₃ ] n-OH (n: 0, 1, 2)

Embedded image CH _3- [SiO (CH ₃ ) ₂ ] _m- [SiO (H) (C
H ₃ )] _l -Si (CH ₃ ) ₃ (l, m: 0 or integer)

Embedded image _{^{R 4 - [SiO (CH 3}} ) 2] k-Si (CH 3) 2 R 4 (K: ^{integer, R 4: -OH, -CH =} CH 2, OCH 3)

Embedded image CH ₃ SiCl ₃ , C ₁₀ H ₂₁ SiCl ₃ , CF ₃ CH
₂ CH ₂ SiCl ₃ , CH ₃ Si (OCH ₃ ) ₃

In addition,

Embedded image A silazane compound of (CH ₃ ) ₃ SiNH—Si (CH ₃ ) ₃ is also useful as the water repellent used in the present invention.

The surface treatment method for the particles of sand or soil with the water repellent may be the method generally used for the surface treatment of powder. For example, it is possible to produce hydrophobic particles by mixing various silicone oils and sand by a mechanochemical method and performing surface treatment.

In addition to the above-mentioned water repellent sand as the hydrophobic particles, fine particles of a polymer having a hydrophobic surface (plastic) can be used. Of these, organosilicone-based compounds are preferable, and polymethylsilsesquioxane is particularly preferable.

It is also possible to use, for example, waste plastic pulverized into particles, whereby the waste plastic is effectively used and the problem of waste disposal of the waste plastic is solved. It is also possible to use these high molecular weight polymers after water repellent treatment.

In addition to the above-mentioned hydrophobic particles as specific examples, for example, hydrophobic granular metal oxides such as silica, alumina, titania, zirconia, vanadium acetate, iron oxide, glass beads, crushed oil shells, Needless to say, hydrophobic particles such as oil sand can be used, but in particular, those whose surface is treated with a silicone water repellent are more preferable. However, the oil shell and the oil sand can be effectively used even if they are not treated with silicone.

The hydrophobicity of the hydrophobic layer can be arbitrarily adjusted, for example, by changing the type of hydrophobic particles or the thickness of the hydrophobic layer.

That is, the hydrophobic layer composed of the hydrophobic particles in the soil of the present invention, depending on the kind, size and shape of the hydrophobic particles constituting the soil, the depth from the soil surface, the control rate of water, etc. It may be selected as needed. For example, the hydrophobic strength can be adjusted by appropriately mixing water-repellent sand that is a hydrophobic particle and ordinary sand that is not treated with a water-repellent agent and that is a non-hydrophobic particle.

When a soil layer is further set on the hydrophobic layer of the artificial water retentive soil structure of the present invention, there is no loss due to wind of hydrophobic particles, and there is no deterioration due to sunlight, etc. There is an advantage that the hydrophobic particles constituting the are excellent in durability.

This embodiment is an artificial water-retaining soil structure having a soil layer containing no water-retaining agent on the hydrophobic layer, for example, sand or soil having a thickness of 10 to 100 mm existing on the hydrophobic layer. If the soil layer is set, the hydrophobic layer is protected from deterioration due to sunlight and scattering due to wind, so that the use of this aspect of the present invention in an area where sunlight and wind are strong does not impair the effect for a long period of time. To be demonstrated.

As described above, the embodiment of the present invention in which the hydrophobic layer is covered with sand or soil can prevent loss of the hydrophobic particles due to wind and deterioration from sunlight because the hydrophobic particles are present in the soil. Therefore, the stability of the hydrophobic layer itself is also excellent for the artificial water-retaining soil structure of the present invention, and since the loss of the hydrophobic particles can be prevented, the thickness of the hydrophobic layer of the artificial water-retaining soil structure can be reduced. There are advantages such as.

Next, in order to manufacture a soil structure comprising the artificial water-retaining soil structure of the present invention, for example, the ground is dug into a certain area and depth, and the artificial space is formed in the ground. The artificial water-retaining soil structure described above may be embedded in the above to artificially form a stratum structure having a hydrophobic layer composed of hydrophobic particles on the soil having a water-retaining agent.

It is sufficient to excavate a certain area to a certain depth, mix the water retention agent with the soil layer, and further bury a hydrophobic layer of arbitrary thickness composed of hydrophobic particles on the soil layer. The layers making up may be similar to the surrounding natural formations, for example.

In order to bury a hydrophobic layer composed of hydrophobic particles having an arbitrary thickness, it is sufficient to lay the hydrophobic particles after forming a soil layer containing a water retention agent on site, and concretely, for example, concrete. Sand and silicone water repellent can be mixed on site using a mixer and mixer of the same kind, and then excavated and laid in the space formed in the ground. It is also possible to work while facing the site while using sand to make the sand water repellent.

In addition, a soil layer previously containing a water retention agent and sand subjected to water repellent treatment were separately filled in a cubic container or bag at a factory, and these were excavated to form a space formed in the ground. It is also possible to first arrange the soil containers or bags containing the water retaining agent first, and then arrange the water-repellent sand containers or bags thereon. If the container is wood, it will corrode in the ground, that is, in the artificial water-retaining soil structure, and if the bag is paper such as a cement bag, which is strong, it can be used in the present method and will corrode in the ground like the container.

The present method can accurately and simply configure the thickness of the soil layer and the hydrophobic layer containing the water retention agent, and the artificial water retention soil structure can be easily obtained by filling and laying other soil constituent layers such as fertilizer. The body can be manufactured in any size (area).

Needless to say, the size of the artificial water-retaining soil structure is not particularly limited, and the desired width and thickness can be set according to the application. A large container having a certain height may be filled with the artificial water-retaining soil structure of the present invention at a factory in advance, and the container may be directly arranged in a space of a certain area dug to the same depth as the height of the container. It is possible.

Further, according to the present invention, without excavating the ground,
It is also possible to design the soil structure of the present invention by laying the artificial water retention soil structure of the present invention on the ground having a finite area and artificially forming a new stratum structure.

If necessary, it is possible to form a special growing environment suitable for agricultural crops by enclosing a certain land consisting of an artificial water retention soil structure with a dome and combining it with an external environment of artificial atmosphere. .

The present invention is constituted as described above, and is aimed at by various factors such as the kinds of the water retention agent and the hydrophobic particles, the thickness of the soil layer and the hydrophobic layer containing the water retention agent, and the combination with other external environment. The evaporation of water in the soil can be suppressed at an arbitrary rate to control the water content of the soil structure, thereby enabling a new and useful method for suppressing the soil water content.

[0064]

EXAMPLES Next, the present invention will be described with reference to examples. The present invention is not limited to this.

Example 1 Acryhope (manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd.), which is a water-retaining agent containing sodium acrylate as a main component, was mixed with Asano silica sand No. 4 (average particle size: about 1000 μm) at a ratio of 0.1% by weight. The mixture was thoroughly mixed to obtain a water retention agent-containing soil.

Next, Asano quartz sand No. 4 (average particle size of about 100)
0 μm) and Asano quartz sand No. 7 (average particle size about 100 μm)
0.3% C ₁₀ H ₂₁ Si (Cl) _{3 for} each 10 kg
/ N-hexane solution (2.5 kg) was poured, the mixture was stirred and left at room temperature for about 12 hours, filtered, washed with water, and dried at 100 ° C.
Silicone-treated hydrophobic silica sand that is hydrophobic particles was obtained.

The water-holding agent-containing soil was placed in a glass container having a diameter of 10 cm and a depth of 30 cm to a depth of 10 cm, and the layer of the silicone-treated sand Asano silica sand No. 4 obtained above was placed on the water-holding agent-containing layer. The artificial water-retaining soil structure was manufactured at a laboratory level in order to confirm the effect of the present invention by setting the depth to 3.3 cm and further setting the layer of Asano silica sand No. 4 to 2 cm. did.

Example 2 Acryhope (manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd.), which is a water-retaining agent containing sodium acrylate as a main component, was mixed with Asano silica sand No. 7 (average particle size: about 100 μm) at a ratio of 0.1% by weight. The mixture was thoroughly mixed to obtain a water retention agent-containing soil.

Next, Asano quartz sand No. 4 (average particle size of about 100
0 μm) and Asano quartz sand No. 7 (average particle size about 100 μm)
0.3% C ₁₀ H ₂₁ Si (Cl) _{3 for} each 10 kg
/ N-hexane solution (2.5 kg) was poured, the mixture was stirred and left at room temperature for about 12 hours, filtered, washed with water, and dried at 100 ° C.
Silicone-treated hydrophobic silica sand that is hydrophobic particles was obtained.

The above water-holding agent-containing soil was placed in a glass container having a diameter of 10 cm and a depth of 30 cm to a depth of 10 cm, and the layer of the silicone-treated sand Asano silica sand No. 7 obtained above was placed on this water-holding agent-containing layer. The artificial water-retaining soil structure was manufactured at a laboratory level in order to confirm the effect of the present invention by setting the depth to 3.3 cm and further setting the layer of Asano silica sand No. 7 to 2 cm. did.

[Comparative Example 1] An artificial water-retaining soil structure was prepared by inserting Asano silica sand No. 4 not treated with silicone in place of the silk cone-treated Asano silica sand of Examples 1 and 2.

Distilled water (50 cc) was poured into each of Examples 1 and 2 and Comparative Example 1, and water was retained in the water retaining agent-containing soil layer through the hydrophobic layer. Next, this was left to stand at room temperature of 35 ° C., and each weight change (water evaporation amount) was measured. As a result, the artificial water-retaining soil structure of the example of the present invention suppressed water evaporation as compared with the artificial water-retaining soil structure of the comparative example.

Example 3 Acryhope (manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd.), which is a water-retaining agent containing sodium acrylate as a main component, was mixed with Asano silica sand No. 4 (average particle size: about 1000 μm) at a ratio of 0.2% by weight. The mixture was thoroughly mixed to obtain a water retention agent-containing soil.

Next, a granular hydrolyzate of CH ₃ SiCl ₃ ,
Polymethylsilsesquioxane (particle size: 800 μm) was used to prepare hydrophobic particles constituting the hydrophobic layer.

The above water-retaining agent-containing soil was placed in a glass container having a diameter of 10 cm and a depth of 30 cm to a depth of 10 cm, and a layer of Asano silica sand No. 4 was set to a depth of 3.3 cm on the water-retaining agent-containing layer. In order to confirm the effect of the present invention, an artificial water-retaining soil structure at a laboratory level is provided so that a hydrophobic layer made of polymethylsilsesquioxane (particle size is 800 μm) is 2 cm in thickness. Manufactured body.

Example 4 Acryhope (manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd.), which is a water-retaining agent containing sodium acrylate as a main component, was mixed with Asano silica sand No. 7 (average particle size: about 100 μm) at a ratio of 0.5% by weight. The mixture was thoroughly mixed to obtain a water retention agent-containing soil.

Next, a granular hydrolyzate of CH ₃ SiCl ₃ ,
Polymethylsilsesquioxane (particle size: 800 μm) was used to prepare hydrophobic particles constituting the hydrophobic layer.

The above water-holding agent-containing soil was placed in a glass container having a diameter of 10 cm and a depth of 30 cm to a depth of 10 cm, and a layer of Asano silica sand No. 7 was set to a depth of 3.3 cm on the water-holding agent-containing layer. And a hydrophobic layer made of polymethylsilsesquioxane (particle size is 800 μm) with a thickness of 2 cm, and finally with a layer of Asano silica sand No. 7 with a depth of 3.3 cm. The artificial water retentive soil structure at the laboratory level was manufactured by providing the above structure.

Example 5 Acryhope (manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd.), which is a water retention agent containing polymeric sodium acrylate as a main component, was combined with Asano silica sand No. 4 (average particle size: about 1000 μm) at a ratio of 0.1% by weight. The mixture was thoroughly mixed to obtain a water retention agent-containing soil.

Next, Asano quartz sand No. 4 (average particle size of about 100
0 μm) and Asano quartz sand No. 7 (average particle size about 100 μm)
0.3% HO-Si (ONa) (C
H ₃₎ - Pour 2.5Kg the _{[OSi (ONa) CH 3]} -OH / n- hexane solution was allowed to stand at after stirring at room temperature for about 12 hours, filtered, washed with water, and dried at 100 ° C., the hydrophobic particles A silicone-treated hydrophobic silica sand was obtained.

The above water-holding agent-containing soil was placed in a glass container having a diameter of 10 cm and a depth of 30 cm to a depth of 10 cm, and the layer of the silicone-treated sand Asano silica sand No. 4 obtained above was placed on this water-holding agent-containing layer. The artificial water-retaining soil structure was manufactured at a laboratory level in order to confirm the effect of the present invention by setting the depth to 3.3 cm and further setting the layer of Asano silica sand No. 4 to 2 cm. did.

Comparative Example 2 An artificial water retentive soil structure was prepared by using Asano silica sand No. 7 in place of the hydrophobic layer made of polymethylsilsesquioxane of Examples 3 and 4.

100 cc of distilled water was poured into Examples 3, 4 and 5 and Comparative Example 2, and water was retained in the water retaining agent-containing soil layer through the hydrophobic layer. Next, this was left to stand at room temperature of 38 ° C., and each weight change (water evaporation amount) was measured. As a result, the artificial water-retaining soil structure of the example of the present invention suppressed water evaporation as compared with the artificial water-retaining soil structure of the comparative example.

The artificial water-retaining soil structure of the present invention according to the above-mentioned embodiment is characterized by simply evaporating the water in the soil as compared with the artificial water-retaining soil structure in the case of mixing the water-retaining agent with the soil. Can be demonstrated to be extremely well controlled, and when scaled up, the soil structure can be improved at the global environment level so that it can sustain water retention of soil for a long period of time in arid areas such as desert areas and is suitable for cultivation of agricultural products. It becomes possible.

It is also demonstrated that the artificial water-retaining soil structure of the present invention extremely quickly penetrates into the soil even when water is poured from the ground surface, passes through the hydrophobic layer, and retains water in the water retention agent.

Example 6 Asano quartz sand No. 4 was placed in a pot made of expanded polystyrene for 10 cm. On top of that, Example 1
10 cm of the water retention agent-containing soil was placed, and the hydrophobic layer of Example 1 was further laid thereon to a thickness of 3 cm. Furthermore, 2 cm of Asano quartz sand No. 4 was put on it. Cotton seedlings were grown in a paper pot having a depth of 10 cm and a diameter of 10 cm made of alluvial soil. A paper pot of this cotton seedling was planted in a polystyrene pot so that the bottom of the paper pot reached the soil layer containing the water retention agent. When water was sprinkled at 40 gr / m ² every week and grown at 35 ° C., cotton grew smoothly. As a comparative example, 3 cm of Asano silica sand was added instead of the above-mentioned hydrophobic layer,
Otherwise, cotton in a paper pot grown under the same conditions as in Example 5 did not grow.

[0087]

EFFECTS OF THE INVENTION According to the present invention, by providing an artificial water-retaining soil structure having a novel structure, the evaporation of water in the soil can be efficiently suppressed. Therefore, a conventional water-retaining agent was simply mixed into the soil. Compared with the case, the effect is efficiently exhibited in the long term.

Further, according to the method for producing an artificial water-retaining soil structure of the present invention, an artificial water-retaining soil structure can be obtained by a relatively easy method, and it is useful to suppress water evaporation in the soil. Very useful in applications. For example, it is used for various agriculture, horticulture such as potted plants, roadside trees, planting trees in parks, etc., but the application of the present invention is not limited and can be applied to all fields.

When this is used for cultivating a plant, it is possible to grow the plant with a small amount of water even in a dry area where the water conditions are extremely severe. For example, large-scale agricultural crops can be cultivated in dry areas where water conditions are severe.

Furthermore, according to the method for suppressing water evaporation in soil, which is characterized by using the artificial water-retaining soil structure of the present invention, adjustment and design of soil water suitable for the intended purpose in advance can be easily carried out. It will be possible.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshiaki Nishimura 2-6-1, Otemachi, Chiyoda-ku, Tokyo Shin-Etsu Chemical Co., Ltd.

Claims (11)

[Claims] 1. An artificial water-retaining soil structure having a hydrophobic layer composed of hydrophobic particles on a soil having a water-retaining agent. 2. An artificial water-retaining soil structure having a hydrophobic layer composed of hydrophobic particles on a soil having a water-retaining agent via a soil layer containing no water-retaining agent. 3. The artificial water retentive soil structure according to claim 1, further comprising a soil layer containing no water retention agent on the hydrophobic layer composed of hydrophobic particles. 4. The artificial water retentive soil structure according to claim 3, wherein the water retaining agent-free soil layer existing on the hydrophobic layer is a soil layer made of sand or soil having a thickness of 10 to 100 mm. 5. The soil portion having a partially non-hydrophobic property is provided inside the hydrophobic layer or through the hydrophobic layer.
5. An artificial water-retaining soil structure according to any one of 4 to 4. 6. The artificial water retention soil structure according to claim 1, wherein the water retention agent is a polymer compound having water retention property. 7. The artificial water retention soil structure according to claim 1, wherein the hydrophobic particles have a particle diameter of 2000 μm or less. 8. The artificial water retentive soil structure according to claim 1, wherein the hydrophobic particles are sand and / or soil particles treated with a water repellent. 9. The artificial water retentive soil structure according to claim 8, wherein the water repellent is a silicone-based or fluorine-based water repellent. 10. Excavating the ground to a finite area and depth,
The artificial water-retaining soil structure according to any one of claims 1 to 9 is artificially buried in a space formed in the ground, and the hydrophobic water-containing particles are formed on the soil having a water-retaining agent. A method for producing an artificial water-retaining soil, which comprises artificially forming a stratum structure having a hydrophobic layer 11. A method for suppressing water evaporation in soil, which comprises using the artificial water-retaining soil structure according to any one of claims 1 to 9.