JPH08298859A - Greening of hillside - Google Patents

Abstract

PURPOSE: To make surface soil resist to erosion due to rainfall or a wind with strong joining to the ground and prepare a growing foundation for plants on a slope even in the case of a bedrock by spraying a specific foundation material for greening a hillside on the slope and efficiently greening the hillside such as a mountain district. CONSTITUTION: A slope is sprayed with a foundation material for greening a hillside containing a water-soluble polymer consisting essentially of an N- vinylcarboxamide such as N-vinylacetamide as a soil binder in an amount of 0.02-1wt.% based on the foundation material for greening the hillside, an air- permeable material such as perlite or vermiculite and further a plant seed and/or a rhizome in soil for greening comprising an organic culture soil consisting essentially of one or more of bark, leaf mold, peat-moss and a farmyard manure. Thereby, the hillside is greened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for greening sloped areas in mountainous areas, sloped areas such as railway tracks and shoulders of expressways, slopes of mountains excavated for housing construction, land reclamation and gravel collection, and coasts. , Especially on an efficient greening method in a land where the rock is exposed and is not suitable for plant growth.

[0002]

2. Description of the Related Art It is often unavoidable to destroy the natural environment in order to ensure convenience, comfort and safety for human life. It is almost impossible to restore the destroyed environment once the green has disappeared due to the destruction of the natural environment. Many methods have been proposed for revegetation of such nature-destroyed land, and much energy has been spent to restore the greenery. Once the nature is destroyed and the green is lost, the top soil, which is the base of plant growth, is easily lost, and is easily washed away or blown away by rain, wind, etc., making restoration of the green extremely difficult. Especially in the sloping land, the topsoil is easily washed away even with a slight rainfall, and the land after losing the topsoil is exposed to rocks and becomes abruptly dry, which is the most important water retention capacity for plant growth. With the loss of fertilizing ability and the loss of organic soil, vegetation is almost impossible by a simple method such as sowing. Even if it is possible to sow and green with artificial soil once, this soil has a weak binding force to the ground and is easily eroded and drained by rainfall, resulting in a large waste of energy and money. It was.

Such difficulties are not only encountered in the development of mountain forest roads, but also on mountain slopes other than forest roads where landslides are prone to occur, railroad or highway shoulders, slopes carved for construction of residential areas, etc. Therefore, conventionally in such slopes growing soil for plants, fertilizers, plant seeds, soil improvers,
Greening has been carried out by spraying culture soil for greening containing a solidifying agent (paste agent). However, the solidifying agent (paste agent) used here is an emulsion of a hydrophobic polymer such as a vinyl acetate polymer or a styrene-acrylic acid copolymer, or a partially neutralized product of polyacrylic acid, polyacrylamide, acrylamide. -Sodium acrylate copolymers, water-soluble polymers such as polyvinyl alcohol, and these are small in amount due to insufficient soil bonding strength or weak weather resistance (light stability, corrosion resistance, etc.). Had allowed soil erosion to take place easily.

[0004]

DISCLOSURE OF THE INVENTION The present invention does not hinder the growth of germination and young shoots, has a strong bond with the ground, and resists erosion due to rainfall and wind after a greening treatment, Even so, the aim is to develop a greening method using soil that can form a plant growth base on a slope.

[0005]

[Means for Solving the Problems] The present invention is applied to a soil for revegetation consisting of organic culture soil as a soil-bonding agent with 0.0
A water-soluble polymer containing 2-1 wt% N-vinylcarboxylic acid amide as a main component and a ventilation material, and further spraying a sloping ground greening base material containing plant seeds and / or rhizomes on the sloping ground. A method for greening a sloping land, a method for greening an sloping land in which the organic culture soil is a culture soil mainly containing at least one of bark, mulch, peat moss, and compost,
A method for greening sloping ground, which is a greening base material for sloping grounds containing perlite and / or vermiculite as a ventilation material, and a soil for greening consisting of organic culture soil in the frame with 0.02 as a binder. Water-soluble polymer containing 1% by weight of N-vinylcarboxylic acid amide as a main component, aeration material, sloping ground containing plant seeds and / or rhizomes. The above objective was achieved by developing a greening method for sloping land, which is characterized by fixing the greening base material with anchor pins or the like.

The organic culture soil used in the present invention is an organic material such as bark, mulch, peat moss, and compost, or a mixture of sand, soil and the like, which is the main material. The material should contain at least 10% by weight, preferably 30% by weight or more. The organic material in the culture soil is not only extremely effective in maintaining the water retention capacity and the fertilization capacity, but also has a high runoff resistance due to rainfall. It has a positive effect on binding.

Further, a porous inorganic material such as perlite or vermiculite is blended for the purpose of reducing the weight of the greening base material and improving the air permeability. If a ventilation material is not mixed, the density of the greening base material will be high, so not only the required amount of greening base material will increase when the construction thickness is the same, but especially when the temperature and humidity are high, the organic soil will be corroded. Therefore, the air permeability of the vegetation base material is reduced in a short time after the construction, which often adversely affects the vegetation after germination. For this reason, it is effective to increase the blending amount in order to reduce the weight and maintain the air permeability, but it is advantageous to blend 2 to 20% by volume in consideration of the rainwater runoff resistance.

The soil binder used in the present invention is N-vinylcarboxylic acid amide homopolymer or N-vinylcarboxylic acid amide.
-A water-soluble polymer containing vinylcarboxylic acid amide as a main component. These water-soluble polymers not only dramatically improve the bonding strength of the organic culture soil to the sloping ground, but also have excellent weather resistance. While various polymer substances that have been used for the purpose of soil improvement and agglomeration have low weather resistance and lose their performance in exposed soil in a short period of time, N
Polymers of vinyl carboxylic acid amides can retain their performance as soil bonding materials for a long period of time even in places where strong sunlight exposure is inevitable, such as the southern slope.

When the poly N-vinyl carboxylic acid amides are used as a soil bonding material, it is essential that they have water solubility, but the soil bonding strength is reduced but they are not easily dissolved in water. Is preferable from the viewpoint of outflow resistance. When it is an N-vinylcarboxylic acid amide homopolymer (including a copolymer of only N-vinylcarboxylic acid amides), the weight average molecular weight is about 500,000 or more (there is no upper limit of the molecular weight as long as it has water solubility. Currently, a high molecular weight polymer having a molecular weight of about 20,000,000 can be produced.) A slightly high crosslinked polymer or a slightly crosslinked polymer has a slightly lower soil bonding strength, but has a better outflow resistance. Weight average molecular weight is about 50
If it is less than 10,000, the bonding strength of the greening base material to the sloping ground will be weakened, and it is not preferable because it is necessary to increase the blending ratio, and the outflow resistance is lowered and the cost is increased. Further, even in the case of a copolymer with another comonomer, a water-soluble or poorly water-soluble comonomer and a water-soluble high-molecular-weight copolymer are excellent bonding materials in terms of outflow resistance.

The poly N-vinyl carboxylic acid amides used as the soil bonding material in the present invention are homopolymers or copolymers of N-vinyl carboxylic acid amides, and as the N-vinyl carboxylic acid amides, N-vinylacetamide, N-vinylformamide, N-methyl-
Examples thereof include N-vinylformamide and N-methyl-N-vinylacetamide, of which N-vinylacetamide is preferred. Examples of comonomers copolymerizable with N-vinylcarboxylic acid amide include (meth) acrylic acid (salt), (meth) acrylamido-2-methylpropanesulfonic acid (salt), vinylsulfonic acid (salt), acrylamide, and hydroxyl group. C1-C3 substituted by
Examples thereof include alkyl (meth) acrylic acid esters, and among these, those having preferable performance include acrylamido-2-methylpropanesulfonic acid (salt),
(Meth) acrylic acid (salt) and vinyl sulfonic acid (salt). Examples of these salts include sodium salts, potassium salts, ammonium salts and the like. Since the performance of the polymer changes depending on the amount of the comonomer compounded, it is desirable that the amount is at most 30% by weight, preferably 10% by weight or less based on the total amount of all the monomers.

The amount of the soil bonding agent used in the present invention is 0.02 to 1% by weight, and a particularly preferable range is 0.05 to 0.5% by weight. 0.0
If it is less than 2% by weight, the drainage resistance to rainwater will be insufficient and the water retentivity of the greening base material will be insufficient, while if it is more than 1% by weight, the drainage resistance will be improved, but the soil will become too hard, Since the number of plants is reduced, rooting and the like are likely to occur, and in any case, the growth of plants is adversely affected.

For the purpose of improving the water retention capacity, the greening base material for sloping ground of the present invention is a partially neutralized product of polyacrylic acid, polyacrylamide type, acrylamide-sodium acrylate copolymer type, polyvinyl alcohol-sodium acrylate type. It is also an effective method to add a water-absorbent resin (polymer water retention agent) which is a cross-linked body of a water-soluble polymer such as starch-sodium acrylate-based, polyvinyl alcohol-based, polyethylene oxide-based. In particular, for the polymer crosslinked body containing N-vinylcarboxylic acid amide as a main component, which is crosslinked to such an extent that it does not dissolve even when swollen in water, the same monomer as the soil bonding material can be used.

Among them, the polymer cross-linked product containing N-vinylcarboxylic acid amide as a main component promotes the germination of plant seeds and assists the growth of vegetation. Therefore, the sloped ground surface can be covered with vegetation in a short time to prevent erosion. It has the effect of enhancing the water retention capacity of the greening base material due to its own water absorption and increasing the bond strength between the greening base material and the ground. Therefore, it is possible to prevent wind erosion due to the drying of the base material after the construction and erosion due to runoff of the greened base material due to rainwater. In addition to organic soil, it promotes soft rock or soilless soil conversion.

Further, the polymer crosslinked body containing N-vinylcarboxylic acid amide as a main component has a water-absorbing property, which is different from a normal water-absorbing resin. Ordinary water-absorbent resin, for example, sodium polyacrylate-based water-absorbing agent is sufficiently swollen with water, it is difficult to water the plant probably because it is stronger than the water-absorbing ability of the plant, water-absorbing resin sufficient water In many cases, water is not supplied to vegetation even if the water is retained, whereas the crosslinked polymer having N-vinylcarboxylic acid amide as its main component has weak water absorption when water itself is retained. It has the ability to supply water to plants and has excellent properties as a water absorbing agent for greening base materials. Furthermore, if necessary, it is possible to add fertilizer to the greening base material. Fertilizers to be compounded are synthetic fertilizers, animal feces such as cabbage and cow dung, fermentation residues, compounded fertilizers, chemical fertilizers, oil dregs, wood chips, ammonium sulfate, ESH.
Examples of the compost include compost (boiled and softened rice husks) and bone meal. It is desirable to use a mixture of fast-acting fertilizer and slow-acting fertilizer.

The properties of the vegetation base material for sloping land having the above-mentioned structure differ depending on the slope of the sloping ground and the ground. When it is suspended in water and created by using a sprayer, it is advantageous to crush the relatively fine grain size, especially organic culture soil in advance so that it can be easily used in the sprayer. When the sandbags are packed and fixed on a slope, the particle size is not particularly problematic, and it is advantageous to use a dry one that is lightweight and easy to carry. The slope of the construction target slope is steep,
When greening a slope, which is an exposed surface of the rock and the fixation of the greening base material is an unstable condition, a slope is previously provided on the slope, or a wire net is fixed with anchor pins. After that, spray it or fix the greened base material packed in sandbags with anchor pins. The construction by the spraying method is excellent in construction method and economical efficiency, and the method by this method is preferable although it depends on the conditions of the construction site.

The suitable range of spray thickness is not constant depending on the ground, the slope direction, the amount of rainfall, the type of growing plant, etc., but the minimum thickness is necessary as a plant growth base, and the thickness may be thin. At least 3c even on grass and herbs
A spray thickness of m, preferably 10 cm is required. Especially in areas where the ground faces south and there is little rainfall, N
-A water retention agent based on vinylcarboxylic acid amide is blended or a spray thickness of 10 cm or more is preferable. By doing so, the adhesiveness of the bonding agent is also assisted, and the death of plants that have germinated and grown due to lack of water can be greatly reduced.

As plant seeds, in consideration of the construction purpose and restoration target, it must be suitable for the climatic conditions of the construction site, have high ground covering ability and soil binding force, have strong germination ability and fertility, and soil Improvement, fertility, and easy availability of seeds are the conditions for selection. However, mixed seeding combining different types of plants is preferable, and when the target plant germinates slowly and the initial growth is slow, it is necessary to use early growing plants to secure the initial covering and binding force. Is. Since the soil of this method is organic, it has the characteristics that herbaceous plants and woody plants that grow naturally around the seeded plants after they have grown easily invade, and plant transitions occur easily to restore natural vegetation.

[0018]

The greening base material for sloped land used in the method for greening sloped land of the present invention is obtained by mixing the soil consisting of organic culture soil with the bonding agent and the aeration material, and further adding the plant seeds. These materials are effective only when they are combined. That is, the organic culture soil itself retains water,
It has fertilizer, air permeability, and water permeability, and has higher heat insulation than general soil, so it has high freezing resistance and freezing resistance of the growth base, and is suitable for germination, growth or vegetation transition of plants. , Which is an extremely effective component, enhances the adhesiveness and water retention of the hydrophilic resin that is the binder, promotes soil conversion of the rainfall erosion resistant soil, and promotes natural transition by the progress of plant transition of vegetation. Effective in restoring vegetation.

Further, while maintaining water retention together with the aeration material, the air permeability and water permeability of the growth base are enhanced. Therefore, the runoff of the growth base due to rainfall is prevented to enhance the rainfall erosion resistance, and the germination and growth of plants are promoted. Promote. Furthermore, since the heat insulation of the growth base is enhanced, the freeze resistance and freeze resistance are greatly improved. As a result, the soil surface binding effect is exerted by the early surface covering, and stable greening can be performed even on a sloped land.

[0020]

【Example】

(Example 1) 100 L of bark compost with a water content of about 30% by weight
(About 50 kg), 10 L of perlite having a particle size of 1 to 5 mm,
1 L each of turf, Japanese pampas grass, and cedar seeds, 500 g of chemical fertilizer, and 50 g of N-vinylacetamide homopolymer having a weight average molecular weight of 3.4 million were sufficiently mixed with a mixer to prepare a greening base material for sloped land. A grid-like wire net with a side of 5 cm was installed on a soft rock ground with a slope angle of about 45 degrees that was carved out for road expansion, and the net was fixed to the rock with an anchor pin every 1 m. The above-mentioned greening base material was sprayed onto this bedrock at an air pressure of 5 kg / cm ² in a spray area of 1 m ² . Since the base material is compressed by air pressure, the thickness is 5
It was cm.

(Example 2) Instead of the N-vinylacetamide homopolymer, N-vinylacetamide having the same weight average molecular weight of 3.4 million was used.
The bedrock was sprayed in the same manner as in Example 1 except that a greening base material containing a vinylacetamide-sodium acrylate copolymer (molar ratio of monomers = 9: 1) was used.

Comparative Example 1 Rock was sprayed on in the same manner as in Example 1 except that the greening base material containing the same amount of polyvinyl alcohol was used instead of the N-vinylacetamide homopolymer.

(Greening situation) 13 days after spraying, there was a daily rainfall of about 50 mm. Observing the slopes constructed after 3 months (there was a small amount of rainfall other than that), it was found that the construction sites of Example 1 and Example 2 showed lush grass growing all over the slopes. However, in the place where the construction of Comparative Example 1 was performed, about 20% of the total area had soil runoff and rocks were exposed.

[0024]

The method for greening a sloping land according to the present invention is
This method is especially effective for revegetation of exposed soilless land such as bedrock and soft rock, and artificially creates a growth base on which plants depend on sloping land, grows plants on this, and restores natural vegetation through vegetation transition. Is effective. The vegetative base material for sloped land of the present invention strongly alleviates the rapid drying of the base, effectively prevents death due to water shortage of vegetation, and improves drainage to prevent runoff of the base material due to rainfall. By promoting the soiling of the soil, it suppresses the weathering action of the ground.

Claims (4)

[Claims] 1. A water-soluble polymer containing 0.02 to 1% by weight of N-vinylcarboxylic acid amide as a soil-bonding agent as a main component to a revegetation soil consisting of organic culture soil, and a ventilation material, and further plant seeds. And / or rhizome-containing greening base material for sloping ground is sprayed onto the sloping surface. 2. The method for revegetation of a sloping land according to claim 1, wherein the organic culture soil is a culture soil mainly containing at least one of bark, mulch, peat moss and compost. 3. The method of revegetation on a sloping land according to claim 1, which is a greening base material for a sloping land, which contains perlite and / or vermiculite as a ventilation material. 4. A soil-bonding agent is applied to a soil for revegetation made of organic culture soil, which is provided with a legal frame and is placed in the frame.
A water-soluble polymer containing 2 to 1% by weight of N-vinylcarboxylic acid amide as a main component, a ventilation material, and a planting base material for sloped land containing plant seeds and / or rhizomes as a soil
Alternatively, a method of revegetation on a sloping land, which comprises fixing the vegetation base material for sloping land packed with sandbags with anchor pins or the like.