JP2000300076A - Water permeable material for plant growing field and underground structure of plant growing field - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a water-permeable material resistant to the lowering of water-conducting function even after the use over a long period and exhibiting good draining property by providing a specific core material and a filter medi um. SOLUTION: The objective water-permeable material 10 is placed under the ground of a plant-growing field. The material is provided with a core material 11 and a filter medium 12 covering at least the upper surface of the core material 11 in laid state. The core material 11 has water-permeability and pressure resistance, the filter medium 12 has a mesh structure and the size of the mesh opening is sufficient for passing the flown down fine particles of soil material. The mesh has uniform mesh size distribution. The filter medium 12 preferably has a coefficient of permeability of >=1×10 deg. cm/sec in the direction perpendicular to the surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a permeable material for a plant growing area, a basement structure of a plant growing area, and a plant growing area suitable for growing plants.

[0002]

2. Description of the Related Art In order to satisfactorily grow plants, it has been conventionally practiced to create soil and underground structures in plant growing areas and plant plants thereon.

The above-mentioned plant growing ground has a structure in which a soil layer such as soil and sand is provided on an underground base. Generally, a plurality of grooves are provided in the above-mentioned basement, and a porous tube is arranged in the groove. Used.

[0004] The above soil and sand layers are classified into three layers, a surface layer, an intermediate layer, and a lower layer, depending on their properties and particle size, and relatively fine granular soil is used for the surface layer. A predetermined amount of fertilizer and water retention material are mixed to obtain soil suitable for growing plants, and the surface layer has a thickness suitable for growing plants. For the intermediate layer below the surface layer, granular sand having a larger particle size than the surface layer is used to support the surface layer and allow excess rainwater or water to permeate, and also to prevent the fine sediment of the surface layer from flowing down. To limit, the thickness of earth and sand particles and the thickness of the middle layer are set. Further, in the lower layer below the intermediate layer, a granular stone having a larger particle size than the intermediate layer is used, supports the surface layer and the intermediate layer, and quickly transfers flowing water from the intermediate layer to the porous tube. To achieve this, the layer thickness and grain size are selected.

[0005] The water that has reached the above-mentioned perforated tube flows into the inside of the perforated tube through a number of holes provided on the surface of the perforated tube. The perforated pipe is arranged so as to have a gradient, and water flowing into the perforated pipe is guided to an external drain.

[0006]

As described above, the conventional plant cultivation site has three layers: a surface layer for growing the plants, a lower layer for promoting drainage to the perforated pipe, and an intermediate layer for connecting the surface layer and the lower layer. It is required that the intermediate layer has a filter function and efficiently drains water while supporting the soil of the surface layer as the intermediate layer, but in reality the filter function is not sufficient. Instead, the soil in the surface layer flows down to the lower layer. In addition, the sediment of the middle layer itself flows down to the lower layer. The soil and sand flowing down to the lower layer flow into the perforated pipe, and settle and deposit in the perforated pipe.

[0007] The water in the perforated pipe is led out to an external drainage ditch by a gradient. However, even if the perforated pipe has a slight gradient, the earth and sand does not flow out, and accumulates in the perforated pipe as described above. There is a problem that the water guide function of the porous tube is reduced.

To solve this problem, a method has been proposed in which the porous tube is covered with a non-woven filter to prevent inflow of sediment into the porous tube. However, the non-woven filter is likely to be clogged. For this reason, there is a new problem that the permeability of the plant growing area decreases in a short period of time.
The result is poor drainage.

Water management is particularly important for turfgrass grown at golf courses, and if the water permeability is reduced as described above and drainage is poor, humidification damage such as root rot may occur. Also, when a large amount of rainfall causes water to stagnate on the turfgrass, the growth of the turfgrass is significantly inhibited.

[0010] In recent years, cold-season turfgrass has been grown at many golf courses. However, the cold-season turfgrass is susceptible to high-temperature damage in the summer season. Function is reduced and eventually summer dies.

Particularly, it is required that the green grass of a golf course (a substantially circular turf band formed around the hole) be kept in an extremely good moisture state. There is.

Therefore, excellent drainage due to high water permeability,
There is a need for a plant growing area that simultaneously satisfies water retention.

Accordingly, the present invention has been made in view of the above-described problems, and has a water-conveying function that is not significantly reduced even when used for a long period of time, and has an excellent drainage property and a plant-growing-ground underground structure. An object of the present invention is to provide a water-permeable material for a plant growing place that can realize the plant growing place.

[0014]

According to the present invention, there is provided a water permeable material for plant growing ground according to the present invention, which is a water permeable material laid underground in a plant growing land, wherein the water permeable material comprises a core material and a filter material. At least the upper surface in the laid state of the material is configured by covering the filter material, the core material has water permeability and pressure resistance, the filter material is in a mesh shape, the mesh The point is that the pores have a size that can pass through the flowing fine particles of the soil material, and that the sizes of the pores are small.

In the case of the above-mentioned conventional nonwoven fabric filter, since the fibers are laminated at random, the passage holes are complicated in the thickness direction of the filter (FIG. 5).
(a): a cross-sectional view of a conventional nonwoven fabric filter), so that the fine particles are easily captured by the filter and clogging is likely to occur. However, since the filter material of the water-permeable material for plant growing areas according to the present invention is in a mesh shape, the passage holes are straight in the thickness direction of the filter material (FIG. 5 (b): the plant growing method according to the present invention). (A cross-sectional view showing an example of a ground permeable filter material), so that fine particles pass through without being trapped. Therefore, clogging hardly occurs.

Further, since the size of the mesh holes of the filter material is small and almost uniform,
It functions as a sieve for separating fine particles (fine particles flowing down) and particles not to pass. As described above, since the size of the mesh hole of the filter material is a size that can pass through the fine particles flowing down of the soil material, particles having a size that can be deposited against the flowing water flow (hereinafter referred to as a deposition size) Do not pass through the filter material.
Therefore, there is little possibility that a deposit is generated in the core material, and there is little possibility that the water guiding function is reduced.

On the other hand, the falling fine particles that have passed through the filter material flow down with running water without being deposited, and are discharged to the outside. The falling fine particles are fine particles that can flow down with water by a gentle flow of water, and are, for example, fine sand and fertilizer dust.

The filter material preferably has a more uniform pore size.

The sand and soil fall from above when the water permeable material is laid. However, by covering the filter material on at least the upper surface of the core material as described above, the sediment size particles are reduced. Can be prevented from invading. More preferably, the entire surface of the core material is coated with a filter material.

On the other hand, since the core material has water permeability, water or the like that has passed through the filter material and entered the core material can flow down well. Further, since the core material has pressure resistance, even when the water permeable material of the present invention is buried in the soil, the core material is not significantly deformed and can maintain good water permeability.

[0021] In the plant growth areas for water-permeable material according to the present invention, in addition, the filter material is preferably hydraulic conductivity in the vertical direction is 1 × 10 ⁰ cm / sec. Or more with respect to that plane. In addition, the said transmission coefficient is measured by the water permeability test of JISA1218.

As mentioned above, it is particularly important to control soil moisture when growing plants that are sensitive to soil moisture and temperature, such as turfgrass. It is preferable that the breeding ground structure has a high water permeability. Therefore, as described above, the water permeability is preferably 1 × 10 ⁰ cm / sec. Or more, and more preferably 1 × 10 ¹ cm / sec. Or more. It is desired that the water permeability does not decrease even after long-term use.

Further, in the water-permeable material according to the present invention, the mesh diameter of the filter material is 0.2 to 3 mm,
The number of mesh holes is 1000 to 50,000 per 100 cm ²
Preferably, the number is

When the pore diameter is more than 3 mm, particles which may be deposited may be transmitted therethrough. Therefore, the pore diameter is preferably 3 mm or less. It is more preferably at most 2.5 mm, even more preferably at most 2 mm. On the other hand, if it is less than 0.2 mm, the water permeability of the filter material may be deteriorated, so that the pore size is preferably 0.2 mm or more. It is more preferably at least 0.3 mm, still more preferably at least 0.4 mm, even more preferably at least 0.6 mm.

The number of mesh holes is 10 per 100 cm ^2.
When the number is less than 00, the water permeability of the filter material may be deteriorated. On the other hand, when the number is more than 50,000, the strength (strength) of the filter material may be weakened, so that the handleability and workability may be deteriorated. 1000-5000 as described above
It is preferably 0/100 cm ² . It is more preferably at least 1200 pieces / 100 cm ² , still more preferably at least 2000 pieces / 100 cm ² . Further, the number is more preferably 20,000 / 100 cm ² or less, still more preferably 17000/100 cm ² or less, and still more preferably 12,000 / 100 cm ² or less.

The size of the pores of the conventional non-woven fabric filter varies greatly. (Since the non-woven fabric filter is formed by randomly arranging the fibers, the pore size cannot be controlled. 1000 holes
It is impossible to manufacture a non-woven fabric filter having a size of 100 cm ² ), while clogging occurs in small pores without passing even fine particles flowing down, while sediment-size particles occur in large pores. However, as described above, the water-permeable material of the present invention has 1,000 to 50,000 holes of approximately uniform size having a hole diameter of 0.2 to 3 mm as described above. Since it is provided with 100 cm ^2, it does not allow sediment size particles to permeate and has good permeability.

The permeable material according to the present invention is characterized in that the core material
Is 1 × 10 at 20% compression ^-2cm / sec. or more
Yes, stress at 20% compression is 1.5tf / m^TwoThat's all
Is preferred.

The water-permeable material must withstand the weight of the soil at the top when laid underground, must also withstand the weight of water added due to rain, water sprinkling, and the like. Etc. must also withstand the weight. It has a sufficient pressure resistance that does not cause much compressive deformation even when such a weight is loaded, and in order to ensure sufficient water permeability, as described above, the water permeability coefficient at 20% compression is 1%.
It is preferable that the stress is not less than × 10 ^-2 cm / sec. And the stress is not less than 1.5 tf / m ² . Furthermore, the water permeability at 20% compression is 1 ×
More preferably, it is at least 10 ^-1 cm / sec. Also 2
More preferably 0% -compression stress is 2.0tf / m ² or more, more preferably stress 5.0tf / m ² or more.

In addition, in the water-permeable material according to the present invention, it is preferable that the core material is a three-dimensional net made of synthetic fiber.

The synthetic fiber three-dimensional net has a large porosity so that a material having high water permeability can be easily obtained, and a thickness for obtaining a predetermined water permeability can be relatively small.
There is an advantage that the volume when buried in the plant growing area is small, and the construction cost is low. Since the conventional plant growing site has a structure in which the perforated pipe is arranged at the bottom of the lower layer, it is necessary to excavate the bottom very deeply, and there is a problem that the construction cost is high.

Furthermore, the core material of the synthetic fiber three-dimensional net-like body is lightweight and flexible even if it has a large plane area, so that it is easy to handle. For example, it can be easily lifted even if it is 50cm wide and 1.5m long, and even a very long core material such as 20m or more can be transported in a rolled shape, Laying may also be performed. In the case of a perforated tube, there is a concern that a heavy machine is required for transportation.

In addition, the core material of the synthetic fiber three-dimensional net can have various shapes, for example, a large flat plate-like structure having a width of 25 cm to 1.5 m and a thickness of 0.5 cm to 10 cm.
A wide water permeable material can also be used.

[0033] The underground structure for plant growing ground according to the present invention has a gradient in which the water permeable material for plant growing ground is disposed in at least 10% of the cultivated ground area, and the water permeable material guides drainage to the outside of the growing ground. That is the gist.

By arranging the water permeable material in 10% or more of the cultivated horizon area as described above, it is possible to improve the water permeable performance of the whole plant cultivation ground. It is preferable that the water permeable material is uniformly arranged on the underground base.

Further, since the water permeable material has the gradient as described above, the drainage can be favorably guided to the outside.

Further, the underground structure of the plant growing area according to the present invention comprises:
A plant cultivation ground underground structure in which plant cultivation soil is disposed above the plant cultivation ground underground base, and 10% of the cultivation ground area
For the above area, a core material having water permeability and pressure resistance was laid on the underground base with a gradient to guide drainage to the outside of the growing ground, and at least the upper surface of the core material was coated with a filter material. The filter material is in the form of a mesh, the pores of the mesh are large enough to pass through the falling fine particles of the soil material, and the size of each pore is small.

As described above, the filter material is hardly clogged and does not transmit the sediment size particles.
Since this filter material is coated on the upper surface of the core material, the core material does not contain the sediment-size particles, and thus the core material has a good water-conducting function. In addition, since the core material is laid with a gradient, it is possible to guide drainage well to the outside.

The water permeable material is preferably disposed at 30% or more of the cultivation horizon area, more preferably at 50% or more.

The plant growing area according to the present invention is that the turfgrass is vegetated on a growing area using the permeable material for the plant growing area or a growing area using the underground structure of the plant growing area. And

It is particularly necessary to strictly control the moisture content of turfgrass, and in this respect, turfgrass cultivated using the permeable material and cultivated land employing the above-described underground structure can grow turfgrass well.

[0041]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Example 1> FIG. 1 is a perspective view showing a first example of a water permeable material for plant growing areas according to the present invention. Is a water permeable material 10 covered with a filter material. FIG. 1
Are not coated with the filter material.

FIG. 2 is a perspective view showing an example in which a plurality of the water permeable materials 10 shown in FIG. 1 are arranged on an underground base of a plant growing area.

The water permeable material 10 is connected to the front and rear side surfaces of the filter material which are not covered with each other by abutting each other. The plurality of water permeable materials 10 have a gradient so as to descend toward the collecting drain pipe 13 as a whole. It is arranged.

The water in the earth and sand enters the core material 11 from above the water permeable material 10 and the like, flows into the collecting drain pipe 13 through the adjacent water permeable material 10, and is further discharged outside the plant growing area. .

The core material 11 may be of any material and shape as long as it has sufficient pressure resistance and water permeability as described above. Cylindrical or stone resin molded product, diameter 5-1
5mm gravel, 4-6 of JIS A5001-1988
No. 1 or a mixture thereof, and a three-dimensional net made of synthetic fiber.

Examples of the material of the synthetic fiber three-dimensional net include polyester resins, polyamide resins (nylon 6, nylon 66, etc.), polyethylene resins, polybutylene resins, polyurethane resins, and the like. Can be mixed and used. It is also possible to use recycled products of these resins.

As a method for producing the above three-dimensional network, the raw resin is heated and melted and extruded linearly from a nozzle having a large number of holes, received on a moving metal net in cooling water, and solidified by cooling while forming a three-dimensional network. And the like.

As the thickness of the core material 11 is smaller, the volume of the water-permeable material is smaller and the construction cost is lower, so it is preferable that the thickness be determined from the pressure resistance and the water permeability of the core material 11.

The thickness of the core material 11 is recommended to be 5 to 100 mm, preferably 10 mm or more, more preferably 20 mm or more, and preferably 80 mm or less, and 70 mm or less.
The following is more preferred.

When the water-permeable material 10 having a small thickness is used, a plurality of the water-permeable materials 10 may be stacked so as to have a suitable thickness.

The filter material 12 has a mesh shape as described above, and the mesh holes are large enough to allow the flowing down fine particles to pass therethrough, and have small variations in the hole sizes. Therefore, water is transmitted without clogging, and the water reaches the core material 11. Further, since the sediment-size particles are not permeated, no sediment is formed on the core material 11 and a good water guiding function is maintained.

Examples of the filter material 12 include a synthetic resin molded mesh or a woven or knitted fabric sealed with a thermoplastic resin (for example, vinyl chloride resin or acrylic resin) or an adhesive. This is preferable because the material is easy to handle when it is applied, and there is little possibility that a portion having a large mesh hole diameter will be generated due to an external force after the application.

The tensile strength and tear strength of the filter material 12 are preferably large, and the tensile strength is preferably 20 kgf / 3 cm or more, and the tear strength is preferably 3 kgf or more, more preferably 30 kgf / 3 cm.
As described above, the tear strength is 5 kgf or more, more preferably the tensile strength is 50 kgf / 3 cm or more, and the tear strength is 7 kgf or more.

In particular, the water-permeable material composed of the core material of the synthetic fiber three-dimensional net and the synthetic resin molded mesh or the woven and knitted filter material exhibits stable performance.

When constructing the plant growing area, the permeable material 1
0 is placed on the underground base, and the lower layer of granular stone, the middle layer of earth and sand, and the surface layer of soil are preferably laid in this order.

At the factory, the core material 11 and the filter material 12
The present invention is not limited to the case where the water-permeable material 10 is used, but the core material may be disposed on the underground base, and then the upper surface of the core material may be covered with a sheet of the filter material.

<Embodiment 2> FIG. 3 is a sectional view showing an underground structure of a plant growing area according to Embodiment 2 of the present invention.

The core material of the water-permeable material used in Example 2 was a three-dimensional net made of polypropylene resin (thickness 30 mm, 20%
The stress at the time of compression is 40 tf / m ² ), and the filter material is a polyester filament mesh-like woven fabric coated with soft vinyl chloride resin (mesh pore diameter 1.0 mm, number of mesh pores 6000/100 cm ² ) [curing mesh “ Arrow Catch, manufactured by Toyobo Co., Ltd.], and the entire surface of the core material was further coated with the filter material to form a water-permeable material.

The permeable material (thickness: 30 mm) was uniformly arranged on the underground base at 50% of the total area of the breeding ground, with a downward slope of 1/100 toward the collecting drain pipe 13 (permeability). Material placement section 6). However, at the time of this arrangement, the filter material at the connection portion of each water permeable material in the direction in which water flows down is removed so that the core materials of the adjacent water permeable materials come into direct contact with each other, and after the arrangement, the connection portion is covered with the filter material. Was. Then, the most permeable material on the downstream side was connected to the collecting drain pipe 13. In addition, granular stones (particle diameter: about 3 to 15 mm) having a thickness of 30 mm were arranged between the permeable materials (the remaining area 50%).

On this permeable material placement portion 6, river sand from Lake Biwa (2.5 mm or less in particle diameter) is spread to a thickness of 200 mm (intermediate layer 2), and then river sand from Lake Biwa (particle diameter 2.5 mm or less) and ground peat moss were mixed at a volume ratio of 9: 1 and spread to a thickness of 100 mm. The bottom surface (on the underground base) and the front side of the underground part of the cultivated land construction site were covered with a waterproof sheet, and water was blocked so as to prevent moisture from leaking to the outside, except for the collecting drain pipes leading to the external drain.

The water permeability of the plant growing area of Example 2 was 44
%, And water was confirmed from the drain 10 minutes after watering.
From this result, it can be seen that the underground structure of Example 2 shows good water permeability (drainage).

In addition to draining the water in the plant growing area, it is possible to adjust the amount of water in the plant growing area by providing a valve in the collective drainage pipe 13 and adjusting the opening of the valve. . The water accumulated in the core material by squeezing the valve reaches the root portion of the plant by capillary action.

<Embodiment 3> The water-permeable material was used to cover one area of the total area of the growing ground.
An underground plant breeding ground similar to that of Example 2 was constructed, except that it was uniformly arranged at 0%.

The water permeability of the plant growing site of Example 3 was 28
%, Indicating good water permeability.

<Comparative Example 1> Except that no permeable material was provided,
The same underground structure for growing plants as in Example 2 was constructed.

The water permeability of the plant growing ground of Comparative Example 1 was 9%.
The drainage was poor because no water permeable material was used.

<Embodiment 4> FIG. 4 is a sectional view showing an underground structure of a plant growing area according to Embodiment 4 of the present invention.

In the fourth embodiment, a porous tube having a large number of holes is used as a core material of the water permeable material, and the same filter material as in the second embodiment is coated on the outer periphery of the porous tube.
0 was set.

The water-permeable material is placed in a comb-like shape on 10% of the total area of the growing ground while the water-permeable material is inclined down 1/100 toward the collecting drain pipe 13 on the underground base (the water-permeable material placement part 1).
6), the downstream end was connected to the collecting drain pipe 13; Then, as in Example 2, a thickness of 250 mm is provided between the water-permeable materials (the remaining area is 90%).
A granular stone (particle size of about 3 to 15 mm) was placed at.

On this water permeable material arrangement portion 16, in the same manner as in Embodiment 2 described above, river sand (with a particle size of 2.5 mm or less) produced from Lake Biwa was deposited to a thickness of 200 mm.
Then, as a surface layer 1, earth and sand obtained by mixing river sand (2.5 mm or less in particle size) from Lake Biwa and ground peat moss at a volume ratio of 9: 1 was spread over the surface to a thickness of 100 mm. The bottom surface (on the underground base) and the front side of the underground part of the cultivated land construction site were covered with a waterproof sheet, and water was blocked so as to prevent moisture from leaking to the outside, except for the collecting drain pipes leading to the external drain.

The water permeability of the plant growing site of Example 4 was 25.
%, Indicating good water permeability.

However, since the diameter of the porous tube as the core material of the water permeable material is required to be 100 mm or more, when laying the water permeable material using the porous tube as the core material, the underground base is made to be larger than that of the second embodiment. It was necessary to dig deeper (at least 120 mm deeper), so the construction cost was higher than in Example 2.

The reason why the water permeability of Example 4 was lower than that of Example 3 in which a permeable material was laid in 10% of the cultivated horizon is that the flow of water was poor because the underground base was dug deep. It is thought that it became.

<Comparative Example 2> Using the same core material as in Example 2 above, the core material was coated with a nonwoven fabric having a basis weight of 200 g / cm ² to form a water-permeable material. Installed.

The water permeability of the plant growing area of Comparative Example 2 was 11
% And poor water permeability (drainage). The reason is that the water permeability of the non-woven fabric coated on the core material is 2.6 × 1
It is considered that the water permeability of the plant growing area was lowered because of the low rate of 0 ^-1 cm / sec. And clogging caused by long-term use.

Table 1 summarizes the values of Examples 2 to 4 and Comparative Examples 1 and 2.

[0077]

[Table 1]

The method for measuring the above values will be described below.

<Thickness of Core Material, Stress at 20% Compression of Core Material> Five square test pieces of 20.0 cm or more were prepared as core material test pieces, and these test pieces were placed in a compression tester [ORIENTEC. The compressive stress is measured using a Tensilon tester type UTC-25 manufactured by KK. The shape of the bottom chuck of the compression tester is a flat plate larger than the test piece, and the shape of the upper chuck is a circular flat plate having a diameter of 15 cm. In the measurement, the test piece is fixed on the bottom chuck and the test piece is compressed by moving the upper chuck downward at a moving speed of 3 mm / min. At this time, the test piece is placed at a predetermined position on the bottom chuck so that the center of the test piece matches the center of the upper chuck as much as possible.

The relationship between the distance between the chucks and the stress is recorded, and the distance Lcm between the chucks when the compressive stress is 1.77 kgf (0.01 kgf / cm ² ) is obtained from the record, and this L is defined as the thickness of the core material.
Further, the compressive stress Pkgf at the time when the distance between the chucks became 0.8 × Lcm was obtained from the above record, and 20 kg of the test piece was obtained from the following equation (1).
The stress ptf / m ² at the time of% compression is calculated. ptf / m ² = 56.6 × Pkgf (1) The average of the stress p of the five test pieces is defined as the stress when the core material is compressed by 20%. The thickness and compressive stress of the water permeable material are
It is almost the same as the thickness of the core material and the stress during compression.

<Permeability of Filter> JIS A1
The water permeability in the direction perpendicular to the filter surface of the filter material is measured by the constant water level permeability test method described in 218.

<Pore Size of Mesh of Filter Material> The filter material was placed on a horizontal plane, the major axis and the minor axis were measured for arbitrary 20 mesh holes, and the average value of the major axis and the minor axis was defined as the individual pore diameter. The average value of the 20 pore diameters is defined as the pore diameter of the mesh of the filter material.

The pore size of the nonwoven fabric is 50 to 200 μm
Are passed through a nonwoven fabric, the average is taken from the particle size distribution of the passed beads, and this value is defined as the pore size.

<Number of mesh holes in filter material> About 100 to 5
An approximately square sample having 00 holes is prepared, the area of the sample and the number of holes are determined, and the number is converted into the number of mesh holes per 100 cm ² . This is performed for three samples, and the average value of the number of mesh holes is defined as the number of mesh holes of the filter material.

The number of holes in the nonwoven fabric was measured by taking an enlarged photograph of the nonwoven fabric with a microscope, counting the number of holes having a size equal to or larger than the above-determined hole diameter, and converting the number to the number of mesh holes per 100 cm ² .

<Permeability of the underground structure of the plant growing area> A normal grass growing area was constructed in the field by constructing the plant growing area, and one year later,
Sprinkle 100g / 1cm ² of water on the surface of the plant growing area for 5 minutes,
Thereafter, the amount of water obtained from the external drain and the elapsed time are measured. The amount of water collected from the drainage ditch during the 30 minutes after watering is measured, and the recovery rate with respect to the watering amount is obtained, which is defined as the water permeability of the underground structure of the plant growing area.

An underground structure in which at least 20% of the input water is recovered within 30 minutes is desirable.

Although the permeable material and the underground structure for growing plants according to the present invention have been specifically described above, the present invention is not necessarily limited to the above-described examples, but may be appropriately modified within a range that can conform to the above-mentioned purpose. Modifications may be made and all of them are included in the technical scope of the present invention.

[0089]

By using the water-permeable material for plant growing areas according to the present invention, or by employing the underground structure of plant growing areas according to the present invention, the water guiding function is not significantly reduced even after long-term use. Plant breeding grounds exhibiting good drainage properties can be obtained. Therefore, for example, the amount of water in the plant growing area can be easily adjusted and managed by adjusting the valve of the drain pipe leading to the outside. Specifically, for example, in the winter season when water usage is low or during the rainy season when rainfall is heavy, open the drain valve to drain water, prevent root rot, and squeeze the bubble in the drain pipe during hot summer or dry season to moisturize. I do. At this time, the water in the core material reaches the root of the plant by capillary action,
In addition, soil temperature can be lowered by moisture retention and evaporation of water from the soil surface layer, and summer withering can be prevented.

In addition, as described above, according to the present invention, as the drainage property is improved, the supply of air into the soil is improved, so that the plant can easily supply oxygen, and root rot and the like can be prevented.

[0091] In particular, in the case of using a three-dimensional net made of synthetic resin as the core material, it is not necessary to dig the basement basement too deeply at the time of construction, so that the construction cost can be reduced. Good workability.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a water permeable material for plant growing areas according to the present invention.

FIG. 2 is a perspective view showing an example of a state in which a plurality of water permeable materials shown in FIG. 1 are arranged on an underground base of a plant growing site.

FIG. 3 is a sectional view showing an underground structure of a plant growing area according to a second embodiment of the present invention.

FIG. 4 is a sectional view showing an underground structure of a plant growing area according to a fourth embodiment of the present invention.

FIG. 5A is a cross-sectional view of a conventional nonwoven fabric filter, and FIG.
FIG. 1 is a cross-sectional view showing an example of a filter material of a water-permeable material for plant growing areas according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Surface layer 2 Intermediate layer 6,16 Permeable material arrangement part 10,20 Permeable material 11 Core material 12 Filter material 13 Collecting drain pipe

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ryoji Morimoto 2-2-2 Dojimahama, Kita-ku, Osaka-Toyobo Co., Ltd. (72) Inventor Kenji Nakagawa 2-2-2 Dojimahama, Kita-ku, Osaka-shi Toyobo Co., Ltd.

Claims (8)

[Claims] 1. A water permeable material laid underground in a plant growing area, wherein the water permeable material includes a core material and a filter material, and the filter material covers at least an upper surface in the laid state of the core material. The core material has water permeability and pressure resistance, the filter material is a mesh, the pores of the mesh are large enough to pass through the fine particles flowing down of the soil material, A water-permeable material for plant growing areas, characterized in that the size of each hole is small. 2. The water-permeable material for plant growing areas according to claim 1, wherein said filter material has a water-permeability in a direction perpendicular to a plane thereof of 1 × 10 ⁰ cm / sec or more. 3. The water-permeable material for plant growing areas according to claim 1, wherein the filter material has a mesh pore diameter of 0.2 to 3 mm and a mesh pore number of 1,000 to 50,000 per 100 cm ^2. . 4. The core material has a water permeability of 1 × 10 ⁻² cm / sec. Or more at 20% compression and a stress of 1.5 tf / m ² or more at 20% compression. 4. The water-permeable material for plant growing areas according to any one of to 3 above. 5. The water-permeable material for plant growing areas according to claim 1, wherein the core material is a three-dimensional net made of synthetic fiber. 6. The permeable material for plant growing ground according to any one of claims 1 to 5, which is arranged in 10% or more of a growing ground area.
And an underground structure for growing plants, wherein the permeable material has a gradient for guiding drainage to the outside of the growing ground. 7. A core material having water permeability and pressure resistance for an area of 10% or more of a cultivated horizon in an underground structure of a cultivated vegetation in which a soil for cultivating a plant is disposed above an underground base of the cultivated land. Is laid on the underground base with a gradient to guide drainage to the outside of the growing ground, wherein at least the upper surface of the core material is covered with a filter material, wherein the filter material is in a mesh shape, and the mesh is The underground structure of a plant growing area, characterized in that the pores are large enough to pass through the fine particles flowing down of the soil material, and the sizes of the pores are small. 8. A breeding ground using the water-permeable material for plant cultivating land according to any one of claims 1 to 5, or a cultivation ground,
A plant breeding ground, characterized in that turfgrass is vegetated on a breeding ground employing the underground structure of the plant breeding ground described in 1 above.