JP2009055875A - Artificial culture soil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an artificial culture soil containing a vegetative organic material, preventing the development of water-repellency even after drying, keeping low viscosity, having moderate water-retention and air permeability and storable for a long time. <P>SOLUTION: The artificial culture soil contains mica on the surface of a vegetative organic material. The coverage of the surface of the vegetative organic material with mica is preferably ≥1.0% from the viewpoint to efficiently suppress the water-repellency of the vegetative organic material, and the content of the mica in the artificial culture soil is preferably within the range of 0.1 to 30 wt.%. The particle diameter of the mica is preferably ≤125 μm. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an artificial soil, and more particularly to an artificial soil having a plant organic material.

  Plant organic materials such as peat moss and coconut peat are widely used in the field of agriculture and horticulture because they are lightweight and have excellent breathability and water retention. However, once these plant organic materials are dried, they become denatured and exhibit water repellency, and even after irrigation, the hydrophilicity does not recover, and the functions necessary for cultivation such as water absorption and water retention are lost. .

Therefore, various proposals have been made so far to prevent the expression of water repellency due to drying of the plant organic material. For example, a technique for mixing clay minerals with plant organic materials (see, for example, Patent Document 1 and Patent Document 2), a technique for adding vegetable organic materials to silica (for example, see Patent Documents 3 and 4) )), And techniques for adding surfactants to plant organic materials have been proposed.
JP-A-9-74896 JP-A-11-266694 JP-A-7-41 JP 2005-124443 A

  However, in the proposed technology in which clay minerals are mixed with plant organic materials, the viscosity becomes high, the fluidity is lowered, and the handling property in the production process is greatly lowered. Further, in the proposed technology for adding silica to plant organic materials, the water retention capacity of silica is too high, and seedling length or root damage due to overhumidity may occur. In addition, the proposed technology for adding surfactants to plant organic materials is excellent in recovery of water absorption after drying of plant organic materials, but is often deactivated due to biodegradation, etc. There was a problem that the preventive effect decreased with time and was not suitable for long-term storage.

  The present invention has been made in view of such conventional problems, and the object of the present invention is that water repellency does not appear even after drying, and the viscosity is maintained low, and the appropriate water retention is achieved. An object of the present invention is to provide an artificial soil having a breathable and organic plant material that can be stored for a long time.

  As a result of intensive studies to achieve the above object, the present inventors have effectively suppressed the water repellency of the plant organic material that appears after drying once the mica is present on the surface of the plant organic material. As a result, the present invention has been found. That is, the artificial soil according to the present invention is characterized by having a plant organic material with mica attached to the surface.

  Here, from the viewpoint of efficiently suppressing the water repellency of the plant organic material, the coverage of the surface of the plant organic material by the mica is preferably 1.0% or more, and the content of the mica in the artificial soil is included. The amount is preferably in the range of 0.1 to 30% by weight. The particle size of the mica is preferably 125 μm or less. In this specification, the coverage of mica is calculated by calculating the total area of mica attached to the surface of the plant organic material from an image taken using a laser microscope “VK-9500” (manufactured by KEYENCE). The total area of this mica is divided by the surface area of the plant organic material. In the present specification, the particle size of mica is an arithmetic average diameter measured by a particle size distribution analyzer “LA-300” (manufactured by Horiba Seisakusho).

  And it is preferable to use what contains 1 type, or 2 or more types selected from peat moss, coconut peat, bark compost, and chip compost as the vegetable organic material.

  In the artificial soil according to the present invention, mica adheres to the surface of the plant organic material, so that even if it is once dried, the subsequent development of water repellency can be suppressed. In addition, since the viscosity is kept low, the productivity and handling properties are prevented from being lowered. Furthermore, the water retention is not as high as when silica is contained, and an overhumid state is not caused. Moreover, the artificial soil of the present invention can maintain the water repellency suppressing effect for a long period of time and is excellent in storage stability.

  The artificial soil according to the present invention has a plant organic material with mica attached to the surface. The mechanism by which the water repellency of the plant organic material is suppressed by the presence of mica on the surface of the plant organic material is not yet clear, but so far the mica on the surface of the plant organic material has a water absorption point. Thus, it is speculated that water may permeate from the gaps between the mica due to the capillary phenomenon to suppress water repellency.

  There is no limitation in particular in the vegetable organic material used by this invention, A conventionally well-known thing can be used. Examples of plant organic materials include peat moss, coconut peat, bark compost, and chip compost, and these may be used alone or in combination. Examples of the shape of the plant organic material include a shape in which plant fibers are intertwined, a shape in which a bark and a wood part of a tree are shredded, and a chip shape in which the bark and the wood part of a tree are crushed.

  As content of the vegetable organic material in artificial soil, the range of 5-100 volume% is preferable normally. A more preferable content is in the range of 20 to 100% by volume.

  The mica used in the present invention is not limited, and conventionally known mica can be used. Examples of mica include muscovite, phlogopite, biotite, sericite, soda mica, Tobe mica, iron mica, muscovite, siderophyllite, eastnite, polyricio mica, triricio mica, lithia mica, chinwald mica, and profit wealth mica. These may be used, and one or more of these may be used in combination. The smaller the particle size of the mica, the more easily the effect of the present invention can be achieved, and specifically, 125 m or less is preferable. A more preferable upper limit is 60 μm.

  The coverage of the surface of the plant organic material with mica is preferably 1.0% or more. This is because if the coverage with mica is less than 1.0%, the effects of the present invention may not be sufficiently obtained. A more preferred lower limit of the coverage with mica is 3%. Further, from the viewpoint of productivity, manufacturing cost, etc., the upper limit value of the coverage with mica is usually 80%. More specifically, when the plant organic material is peat moss, the mica coverage is preferably 7% or more, as shown in the examples described later.

  The mica content in the artificial soil is preferably in the range of 0.1 to 30% by weight. If the content of mica in the artificial soil is less than 0.1% by weight, the effects of the present invention may not be sufficiently obtained. On the other hand, when the content of mica in the artificial soil exceeds 30% by weight, dust scattering increases in the manufacturing process, and the working environment and productivity may be lowered and the manufacturing cost may be increased. The more preferable content of mica in the artificial soil is in the range of 2 to 10% by weight.

  In order to attach mica to the surface of the plant organic material, for example, the plant organic material and mica may be put into a mixing device and mixed with stirring. At this time, in order to efficiently attach mica to the surface of the plant organic material, the surface of the plant organic material should be slightly wet, and when using a plant organic material with a low water content It is recommended to hydrate. The amount of water added is preferably such that the water content of the plant organic material is usually 40% or more.

  The amount of mica added to the plant organic material may be appropriately determined from the type and particle size of the mica so that the coverage with the mica is in a desired range, but is usually 1 per 100 parts by weight of the plant organic material. A range of ˜20 parts by weight is preferred. In the artificial soil of the present invention, mica may exist in a free state other than the one attached to the surface of the plant organic material.

  Further, from the viewpoint of further suppressing the water repellency of the plant organic material, a surfactant may be further added to the plant organic material. When the surfactant is powder, the surfactant may be added to the mixing device together with the plant organic material and adhered to the surface of the plant organic material. When the surfactant is an aqueous solution, the aqueous solution may be sprayed on the surface of the plant organic material to adhere to the surface of the plant organic material. Examples of the surfactant include soap, sulfated oil, polyoxyethylene alkyl ether sulfate, alkyl sulfate ester salt, alkylbenzene sulfonate, alkane sulfonate, α-olefin sulfonate, N-acyl amino acid salt, Anionic surfactants such as dialkylsulfosuccinates and alkylnaphthalenesulfonates; Cationic surfactants such as alkyltrimethylammonium salts and alkylpyridinium salts; polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene fatty acid esters And nonionic surfactants such as polyhydric alcohol fatty acid esters; amphoteric surfactants such as betaine and sulfobetaine.

  In addition, when peat moss is used as a plant organic material, peat moss generally has an acidity of about pH 3.5 to 5.5. Therefore, pH is adjusted by further adding and mixing slaked lime, quick lime, bitter lime, calcium carbonate, etc. It is preferable to do this.

  A conventionally known apparatus can be used as the mixing apparatus, and examples thereof include a paddle mixer, a concrete mixer, and a flat mixer. What is necessary is just to determine suitably as mixing conditions from the kind of apparatus, a processing amount, etc. For example, in the case of a flat type mixer (a cocoon diameter: 63 cm, a cocoon depth: 35 cm), it is about 3 minutes at a rotational speed of 60 revolutions / minute.

  The artificial soil of the present invention may contain other components in addition to the plant organic material as long as the effects of the present invention are not impaired. Examples of the other components include vermiculite, pearlite, zeolite, black clay, true sand soil, Kanuma soil, Kuroboku soil, rice husk kun charcoal, and charcoal. Further, fertilizers and agricultural chemicals may be contained in the artificial soil of the present invention.

  As fertilizers, for example, N, P, K, Ca, Mg, S, B, Fe, Mn, Cu, Zn, Mo, Cl, Si, Na, etc., especially N, P, K, Ca, Mg supply sources And inorganic substances and organic substances. As such inorganic substances, ammonium nitrate, potassium nitrate, ammonium sulfate, ammonium chloride, ammonium phosphate, sodium nitrate, urea, ammonium carbonate, potassium phosphate, superphosphate lime, molten phosphorus fertilizer (3MgO · CaO · P2O5 · 3CaSiO2) Potassium sulfate, potassium salt, lime nitrate, slaked lime, carbonated lime, magnesium sulfate, magnesium hydroxide, magnesium carbonate and the like. Organic substances include chicken dung, beef dung, amino acids, peptone, Mieki, fermented extract, calcium salts of organic acids (citric acid, gluconic acid, succinic acid, etc.), fatty acids (formic acid, acetic acid, propionic acid, caprylic acid, And calcium salts of capric acid, caproic acid and the like.

  Examples of the agrochemicals include those described in “Agricultural Chemicals Handbook 2001 Version” (11th edition, November 1, 2001, issued by the Japan Plant Protection Association). Although the specific example is shown below, it is not limited to these.

  As the insecticide, for example, organophosphorus insecticides such as CYAP agent, MPP agent, MEP agent, ECP agent, and pyrimiphosmethyl agent; carbamate agents such as NAC agent, MIPC agent, BPMC agent, PHC agent, XMC agent, etiophencarb agent Insecticides; Arethrin, Resmethrin, Permethrin, Cypermethrin, and other pyrethroid insecticides; Cartap, thiocyclam, Neristoxin, such as Bensultap, Midacloprid, Acetamiprid, Nitenpyram, Thiacloprid, Neonicotinoid insecticides such as thiamethoxam; insect growth regulators such as buprofezin, isoprothiolane, diflubenzuron, teflubenzuron; benzoepin, fipronil, pymetrozine, chlorfenavir, diafenthiuron Synthetic insecticides such as insecticides, natural insecticides such as pesticides, delices, nicotine sulfate, machine oil, rapeseed oil, etc .; acaricides such as kelsen, phenisobromolate, tetradiphone, BPPS; DD Agents, DCIP agents, methyl isothiocyanate agents, dazomet agents, etc .; fumigants such as methyl bromide agents, chloropicrin agents, carbam agents, carbam sodium salts, cyanide agents; BT agents, spinosad agents, boberia -Biological pesticides such as bronniati and verticillium / recani.

  Examples of the bactericides include copper bactericides such as inorganic copper, organic copper, nonylphenol sulfonate, DBEDC, and the like; inorganic sulfur, zinc sulfate, bicarbonate, hypochlorite, etc. Inorganic bactericides; organic sulfur bactericides such as dineb, manneb, manzeb, ambam, and polycarbamate; organophosphorus bactericides such as IBP, EDDP, torquelophosmethyl, fosetyl, etc .; fusalides, tricyclazole Melanin biosynthesis inhibitors such as thiophanate methyl, benomyl, thiabendazole, and dietofencarb; dicarboximide fungicides such as iprodione and procimidone; oxycarboxylin and mepronil Acid amide fungicides such as antibacterial agents, flutolanil agents, and flametopyr agents; Sterol biosynthesis inhibitors such as Hong, Vitertanol, fenbuconazole, and microbutanyl; methoxy acrylate fungicides such as azoxystrobin, cresoxime methyl, trifloxystrobin, and methminostrobin; pyrimethanil, Anilinopyrimidine fungicides such as mevanipyrim and cyprodinil; Synthetic antibacterials such as teclophthalam and oxolinic acid; Soil fungicides such as flusulfamide, hydroxyisoxazole, echromesole, and tazomet; propenazole , Other synthetic fungicides such as acibenzoral S methyl, isoprothiolane, ferrimzone, etc .; antibiotics such as plastosidine S, kasugamycin, polyoxin, validamycin, streptomycin, etc .; machine oil Rapeseed agents, natural product fungicides such as soybean lecithin; versus antimicrobial agents, shiitake mycelium extract, fungicide, etc. from organisms such as Agrobacterium radiobacter agents.

  As herbicides, for example, phenoxy acid herbicides such as 2,4-PA agent, MCPA agent, MCPB agent, MCPP agent, triclopyr agent, and clomeprop agent; IPC agent, phenmedifam agent, desmedifam agent, bencho curve And carbamate herbicides such as orthobencarb agent; acid amide herbicides such as DCPA agent, alachlor agent, bretiracrol agent, metolachlor agent; urea such as DCMU agent, linuron agent, ciduron agent, diimron agent Sulfonylurea-based herbicides such as bensulfuron methyl agent, ethoxysulfuron agent, pyrazosulfuron ethyl agent; pyrimidyloxybenzoic acid-based herbicides such as pyriminobac methyl agent and bispyribac sodium salt; CAT agent, Triazine herbicides such as atrazine, simethrin, and amethrin; Diazine-based herbicides such as basil, promacil, butaphenacyl, and lenacyl; diazole-based herbicides such as pyrazolate, pyrazoxifene, and benzophenap; bipyridylium herbicides such as paraquat and diquat; piperophos, Organophosphorus herbicides such as Amiprofos methyl and Butamifos; Amino acid herbicides such as Glyphosate, Bialaphos and Glufosinate; Other organic herbicides such as Ioxinyl, Bifenox and DBN; Chlorates And inorganic herbicides such as humectants and cyanate agents; biological herbicides such as Xanthomonas campestris.

  Examples of plant growth regulators include, for example, ethylene agents such as ethephone agents; auxin agents such as indole butyric acid agents, ethiclozate agents, and cloxyphonac agents; cytokinin agents such as benzylaminopurine agents and forchlorphenuron agents; maleic acid Auxin antagonists such as hydrazide agents; Other plant growth regulators such as isoprothiolane agents, oxine sulfate agents, calcium peroxide agents; biological origins such as chlorella extract, mixed herbal extract, shiitake mycelium extract Plant growth regulators and the like.

  Examples of the attractant include insect pheromone attractants such as Little A agent, beet armor agent, and Diamo lua agent; and other attractants such as a pinene oil agent and a methyl eugenol agent.

  Examples of the repellent include dilam, thiuram, petroleum asphalt, iminotadine acetate, bishydroxyethyldodecylamine and the like.

  Examples of the rodenticide include monofluoroacetate, coumarin, chlorofacinone, difacin, zinc phosphide, thallium and the like.

  The artificial soil of the present invention may be, for example, one obtained by mixing the above-described various components and then drying and molding into a predetermined shape as necessary. A conventionally known method such as compression molding can be used as the molding method. Examples of the molded shape include a spherical shape, a cylindrical shape, and a flat plate shape, and may be appropriately determined depending on the application.

  Alternatively, the artificial soil of the present invention may be a granular soil obtained by adding and mixing a binder in addition to the above-mentioned various components and granulating. The granulation method is not particularly limited. For example, after adding and mixing a binder and moisture to the various components described above, the mixture may be put into a rotating drum or a rotating pan and rolled to be granulated. Examples of the binder include vinyl binders such as polyvinyl alcohol, acrylic resin binders, polycarboxylic acid binders, and the like. The particle size of the granulated particles is preferably about several mm from the viewpoint of handleability.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these examples at all.

Example 1
100 parts by weight of peat moss was put into a paddle mixer, and when peat moss was crushed, 20 parts by weight of phlogopite (average particle size: 56 μm) and 50 parts by weight of water were further added and stirred to the surface of peat moss. Deposited phlogopite. Then, 25 parts by weight of pearlite and 50 parts by weight of pure sand were added as other materials and mixed until uniform to obtain artificial soil.
The produced artificial soil was photographed using a laser microscope “VK-9500” (manufactured by KEYENCE), and the coverage of the peat moss surface with mica was calculated from the photographed image. In addition, after drying the prepared artificial soil for 36 hours in an oven at 70 ° C., 50 mL was packed in a cylindrical container (diameter: 50 mm, height: 25.5 mm) and water was absorbed on the bottom surface. Was calculated. The results are shown in Table 1. In addition, the value in a table | surface is the average value measured repeatedly 3 times.

Example 2
100 parts by weight of peat moss was put into a paddle mixer, and when peat moss was crushed, 5 parts by weight of muscovite (average particle size: 73 μm) and 40 parts by weight of vermiculite were added, and 50 parts by weight of water was further added. Stir and mix until homogenous to make an artificial soil. Then, in the same manner as in Example 1, the coverage ratio and water absorption amount of mica on the peat moss surface were calculated. The results are shown in Table 1.

Example 3
100 parts by weight of coconut peat is put into a paddle mixer, and 20 parts by weight of phlogopite (average particle size: 125 μm) and 200 parts by weight of water are further added and stirred when coconut peat is crushed. The phlogopite was attached to the surface of the glass. Next, 20 parts by weight of charcoal, 20 parts by weight of vermiculite, and 20 parts by weight of pearlite were further added as other materials and mixed until uniform to obtain artificial soil. Then, in the same manner as in Example 1, the coverage ratio and water absorption amount of mica on the coconut peat surface were calculated. The results are shown in Table 1.

Example 4
100 parts by weight of coconut peat was put into a flat mixer, and 10 parts by weight of phlogopite (average particle size: 36 μm) and 50 parts by weight of water were further added and stirred when the coconut peat was crushed. A phlogopite was attached to the surface of the coconut peat. Next, 35 parts by weight of zeolite and 10 parts by weight of pearlite were further added as other materials and mixed until uniform to obtain artificial soil. Then, in the same manner as in Example 1, the coverage ratio and water absorption amount of mica on the coconut peat surface were calculated. The results are shown in Table 1.

Example 5
100 parts by weight of bark compost was put into a flat mixer, and 1 part by weight of muscovite (average particle size: 23 μm) was added and stirred when the bark compost was crushed to obtain artificial soil. Then, in the same manner as in Example 1, the coverage of the bark compost surface with the mica and the amount of water absorption were calculated. The results are shown in Table 1.

Example 6
100 parts by weight of bark compost was put into a flat mixer, and 3 parts by weight of muscovite (average particle size: 40 μm) was added and stirred when the bark compost was crushed, and muscovite was applied to the surface of bark compost. Was attached. Next, 4 parts by weight of rice husk kun charcoal and 2 parts by weight of vermiculite were further added as other materials and mixed until uniform to obtain artificial soil. Then, in the same manner as in Example 1, the coverage of the bark compost surface with the mica and the amount of water absorption were calculated. The results are shown in Table 1.

Example 7
100 parts by weight of chip compost is put into a flat mixer, and 2.5 parts by weight of muscovite (average particle size: 31 μm) is put into the place where chip compost is crushed and stirred to the surface of chip compost. A muscovite was attached. Next, 5 parts by weight of Kanuma soil was further added as another material and mixed until uniform to obtain artificial soil. Then, in the same manner as in Example 1, the coverage of the chip compost surface by the mica and the water absorption amount were calculated. The results are shown in Table 1.

Example 8
100 parts by weight of chip compost was put into a flat mixer, and 1 part by weight of muscovite (average particle size: 25 μm) was added and stirred when chip compost was crushed, and muscovite on the surface of chip compost Was attached. Next, 40 parts by weight of black clay was added as another material, and mixed until uniform to obtain artificial soil. Then, in the same manner as in Example 1, the coverage of the chip compost surface by the mica and the water absorption amount were calculated. The results are shown in Table 1.

Comparative Examples 1-8
Artificial soils were produced in the same manner as in Examples 1 to 8 except that mica was not used, and the water absorption was calculated in the same manner as in the examples. The results are shown in Table 1.

  As is apparent from Table 1, the water absorption is increased by attaching mica to the surface of the plant organic material. That is, water repellency is suppressed by attaching mica to the surface of the plant organic material.

(Effect of coverage by mica)
100 parts by weight of peat moss is put into a paddle mixer, and when peat moss is crushed, a predetermined part by weight of muscovite (average particle size: 23 μm) and 50 parts by weight of water are further added and stirred to be uniform. To make artificial soil.
The produced artificial soil was calculated in the same manner as in Example 1 to calculate the coverage of the peat moss surface with mica and the water absorption of the produced artificial soil. The results are shown in Table 2. In addition, the value in a table | surface is the average value measured repeatedly 3 times.

  As understood from Table 2, as the peat moss surface coverage with mica increased, the amount of water absorbed by the artificial soil increased.

(Storage stability test)
Predetermined amounts of two types of mica shown in Table 3 (average particle diameters 5 μm and 36 μm) were added to 100 parts by weight of peat moss, and mica was adhered to the surface of peat moss. These peat moss were dried in an oven at 70 ° C. for 24 hours. Then, in a 150 mL disposable cup (water surface area: 23.8 cm ² ) containing 100 mL of pure water, 5 mL of the dried peat moss is gently floated on the water surface to a uniform thickness, and the peat moss is completely filled with water. The time until soaking was measured. The results are shown in Table 3. In addition, the measured value in a table | surface is the average time measured repeatedly 3 times.

  As a comparative experiment, instead of adding mica, 0.1 mL of a surfactant (5% solution of polyoxyethylene alkylphenyl ether) and 0.9 mL of pure water were added dropwise to 50 mL of peat moss and mixed as above. Then, the time until water completely penetrates into peat moss was measured. The results are shown in Table 3.

  Further, as a comparative experiment, for the peat moss not subjected to the surface treatment, the time until water completely penetrates into the peat moss was measured in the same manner as described above. The results are shown in Table 3.

As understood from Table 3, the peat moss not subjected to the surface treatment did not soak water even after 1800 seconds. Moreover, in the peat moss which added surfactant to the surface, the time until water soaked became longer as the number of days after the treatment passed. That is, the hydrophilic effect by the surfactant was deactivated over time.
On the other hand, all of the peat moss with mica attached to the surface soaked water in a shorter time than the initial value of peat moss with the surfactant added to the surface, and high hydrophilicity was observed. Moreover, the change in hydrophilicity over time was small. In addition, the hydrophilicity of peat moss due to the addition of mica was higher as the mica particle size was smaller and the amount added was higher.

(Evaluation of physical properties of plant organic materials due to differences in surface treatment agents)
1000 mL of peat moss (water content 40%) and 50 mL of mica or clay material (zeolite, bentonite, kaolin) or silica as a surface treatment agent were put into a 2 L bag and mixed. Next, water was added so as to have a moisture content of 55% and further mixed to prepare peat moss having a surface treatment agent attached to the surface.
Various physical properties of the produced peat moss were measured by the following methods. Table 4 shows the measurement results.

(Hydrophilic)
After the prepared peat moss was dried in an oven at 70 ° C. for 24 hours, 5 mL of the peat moss was placed in a 150 mL disposable cup (water surface area: 23.8 cm ² ) containing 100 mL of pure water so as to have a uniform thickness. Gently floated on the surface of the water, and the ratio of water soaked after 15 minutes was measured visually.

(Liquidity)
After placing the prepared peat moss on a sieve having an opening of 4.75 mm, the sieve was vibrated for 60 seconds. And the ratio which passed the sieve was calculated and it was set as the parameter | index of fluidity | liquidity. In addition, the measured value in a table | surface is an average value measured repeatedly 3 times.

(Gas phase rate)
The prepared peat moss was filled in a container in which two 100 mL cylindrical containers (diameter 50 mm, height 51 mm) were connected, and water was soaked into the whole peat moss by irrigating from the upper surface. Then, it was placed on a mesh having a mesh size of 0.5 mm and left for 4 hours. Thereafter, using a soil three-phase meter “DIK-1130” (manufactured by Daiki Rika Kogyo Co., Ltd.), the gas phase rate of the lower cylindrical container connected to the two containers was measured. Two cylindrical containers are connected because a volume of 100 mL or more is required for measuring the gas phase rate, but the volume decreases when peat moss contains water. Moreover, the measured value in a table | surface is the average value measured twice repeatedly.

  As understood from Table 4, the hydrophilicity of peat moss to which the surface treatment agent was added showed a high value of 70% or more regardless of the type of the surface treatment agent. In contrast, peat moss to which no surface treatment agent was added showed a low value of 10%. On the other hand, the fluidity of peat moss was 44% or more when mica and silica were added to the surface, whereas it was as low as 35% or less when clay was added to the surface and the viscosity was high. In addition, the vapor phase rate of peat moss was as low as 3 to 5% in the case of adding clayey material and silica, and as high as 12% in the case of peat moss without the addition of a surface treatment agent. The peat moss was 8% and 9%. When the gas phase ratio is low, the water retention is high but the air permeability is low. On the other hand, when the gas phase rate is high, the water retention is low but the air permeability is high. Therefore, the peat moss with mica added to the surface had a good balance between water retention and air permeability, whereas the peat moss with clay material and silica added to the surface had high water retention but low air permeability. The peat moss to which no agent was added had high air permeability but low water retention.

  The artificial soil of the present invention is useful because it does not exhibit water repellency even once dried, is kept low in viscosity, has appropriate water retention and air permeability, and can be stored for a long time.

Claims (5)

  Artificial soil characterized in that mica has plant organic material attached to the surface.   The artificial soil according to claim 1, wherein a coverage of the surface of the plant organic material by the mica is 1.0% or more.   The artificial soil according to claim 1 or 2, wherein the content of the mica in the artificial soil is in the range of 0.1 to 30% by weight.   The artificial soil according to any one of claims 1 to 3, wherein the mica has a particle size of 125 µm or less.   The artificial soil according to any one of claims 1 to 4, wherein the plant organic material includes one or more selected from peat moss, coconut peat, bark compost, and chip compost.