JP2000166374A - Greening method for slope and lawn for greening slope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently green a slope by planting lawn seedlings only at a specific position on the slope having its crest. SOLUTION: When a slope 2 having its crest 1 is greened, the lawn seedlings are planted only on the crest 1 and the planted lawn grows along the slope 2 until the slope is greened. The objective lawn for greening slopes 2 preferably has excellent ability to cover the slopes with high proliferation and soil holding and the specie of this lawn is 'MIYAKO'. This greening method is particularly effective for relatively short slopes of, for example, rice paddy levees or irrigation channels that have the flat crests of several tens centimeters and these flat crests are utilized as the working paths from the view points of the safety for the crest works and of the scene restoration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for greening a slope having a top.

[0002]

2. Description of the Related Art Conventionally, it takes one year to several years to recover vegetation on a slope caused by cut and embankment, and collapse during soil erosion during that time has been a problem. Therefore, some means of protecting the topsoil is required to prevent collapse. There are the following three methods. The first is the installation of artificial objects such as concrete blocks and covering materials, and the second is greening with seedlings and seeds such as turf and low-shrub, and direct spraying on slopes is the mainstream. Third, a combination of the two.

In general, installation of an artificial object for the purpose of protecting a slope requires the highest cost and affects the landscape. On a short slope where the loss of landscape is often close to the living space,
Often questioned. Also, it is difficult to reuse the artifacts during reconstruction. Next, slope greening by mechanical spraying of seeds and seedlings is not a practical method due to profitability and technical problems when the construction scale is small.

[0004] Therefore, the protection of the ground,
Considering cost and landscape, greening by planting seedlings directly on the slope is realistic, but it is a work on slopes. The higher the number, the higher the construction unit price.

[0005] The collapse of the slope is caused by collapse of the slope of the slope or occurrence of rill erosion due to raindrops, and depending on the conditions, is relatively gentle and requires several months or more at the earliest. In particular, when the top is used as a living space such as a walking route, the collapse of the shoulder, which is the boundary between the top and the slope, is most likely to occur, which has accelerated the erosion to the collapse.

Although cultivated species of Japanese turf are used for various purposes such as golf courses, parks and green areas, and river landscapes, they are not based on the process of selection and breeding. It is doubtful that they have the trait. In particular, the traits necessary for slope planting have not been clarified.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to efficiently green a slope.

[0008]

According to the present invention, there is provided a method of greening a slope having a top, wherein a turf seedling is planted only at the top, the turf grows to the slope, and the slope is greened. A method of revegetating a slope, or a slope revegetation turf that revegetates a slope, characterized in that it has excellent coverage and breeding properties. In the slope greening turf, which is characterized by being excellent in soil retention, the slope greening turf, or in the slope greening turf, the turf is characterized by a variety name "Miyako" It is on the grass for slope greening.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

[0010] The present invention clarifies the traits of Japanese turf necessary for slope planting, selects Japanese turf lines having the traits, demonstrates the necessity of the traits, and finally, It was obtained by studying the planting method to make use of.

It has been found that the traits necessary for planting turf on the slopes are cover growth and soil retention of the root system. The overgrowth is a factor that enables early covering of bare ground, and a turf line excellent in overgrowth was selected by examining the number and elongation of runners generated from turf seedlings. next,
Among them, turf lines with excellent soil retention were selected.
Soil-retaining lines were selected by investigating the amount and distribution depth of rhizomes.

[0012] In terms of the overgrowth of the turf, the average number of stolons generated from one vegetative stem having a length of 20 cm 4 months after planting is about 40.6 ± 17.21 or more. desirable. 17.21 is the standard deviation. In the soil retention of the root system, the distribution depth of the rhizome after one year from the planting was an average value of 5.8 ± 0.5.
It is desirable that it is about 7 cm or more. Note that 0.57
Is the standard deviation. The environmental conditions are as follows. In a sunny place south of Kanto, planting is conducted in early April, and the fertilization amount during cultivation is at least a nitrogen component of 20 g / m ² .

Using these selected lines, the effectiveness of the selected trait was demonstrated, and a planting method that makes the most of the trait was found. Unlike the conventional method of planting directly on the slope, as shown in FIG. 1, turf seedlings (sods) 3 are planted only on the top end 1, and the breeding turf 4 replaces the slope 2 due to the growth of the turf itself. Cover.

According to the present invention, the slope is not directly protected in the early stage of planting. However, since the top 1 is protected, the collapse of the slope can be suppressed, and the vegetation of the top 1 makes it difficult for water to form. Therefore, it is possible to indirectly suppress the rill erosion. Therefore, slope 2
It takes several months to one year for the coating to completely cover, without catastrophic collapse.

The present invention has a flat top with a width of several tens of cm and a law length of 0.4 to 2, for example, a levee or a drainage channel.
This is particularly effective for a slope relatively short as m. In particular, it is most effective on the ridge where the top is the work path from the viewpoint of improving the safety of the top end work and restoring the landscape.

An embodiment of the present invention will be described below.

<A> Variety of turf to be tested First, about 300 native lines and varieties of Japanese turf were collected, and those with good growth and low natural grass appearance were selected from among them. We chose six kinds of noshiba (grass species name), ordinary Kouraishiba (grass species name), and improved Japanese turf "Miyako", "Haruka", "Misato", and "Hayato". "Miyako", "Haruka", "Misato", "Hayato"
Are varieties registered under the Ministry of Agriculture, Forestry and Fisheries Seed and Seedling Law,
No. 4300, No. 5868, No. 6269, No. 586
Registered as No. 9.

[0018] The traits required for slope planting are, firstly, excellent coverage and proliferation relating to the number of occurrences of stolons, and secondly, excellent soil retention relating to a large amount of rhizomes and root depth. We paid attention to. In addition, the characteristics of overgrowth can save the amount of seedlings planted by early covering of joints, and the characteristics of soil retention can avoid drought damage to vegetation. The creeping stalk is a vegetative stem extending on the ground surface, and the rhizome is a vegetative stem extending underground.

The environmental conditions for the test for the growth of the cover are as follows. In a sunny place south of Kanto, planting is conducted in early April, and the fertilization amount during cultivation is at least a nitrogen component of 20 g / m ² .

<B> Test of Coat Proliferation As a test 1 of coat multiplication, six types of Noshiba, Kouraishiba, and improved Japanese turf (Miyako, Haruka, Misato, Hayato) were 20 cm long after 4 months from planting. The number of creeping stems generated from two stems (crawling stems and rhizomes) and their total elongation were compared, and the results are shown in Table 1.

[0021]

[Table 1]

As a test 2 for cover growth, "Miyako", which has a high number of crawling stems, was selected, and a single plant of Noshiba was used as a control for planting 4 from a vegetative stem (crawling stem or rhizome) having a length of 20 cm. The number of creeping stalks after months and the amount of elongation were compared, and the results are shown in Table 2. The numerical values in Table 2 indicate the average values of the five test sites, and the LSD indicates the least significant difference.
The values in parentheses indicate the standard deviation. The average number of creeping stalks from one vegetative stem of "Miyako" was 40.6, which was significantly higher than that of Noshiba, about five times.

[0023]

[Table 2]

<C> Soil Retention Test As shown in FIGS. 2 and 3, planting 1
Years later, a columnar object (construction was made of a green leaf above-ground part 31, a rhizome 3)
The amount of soil that the plant can hold is compared at the height (average value) of 2, root 33, soil 5), and the results are shown in Table 3. FIG.
FIG. 3 is a view showing a state in which the soil 5 is attached, and FIG. 3 is a view in which the soil 5 is removed. In FIG. 2, the soil holding amount indicates the depth from the ground to the deepest part where the soil 5 is attached (the height is replaced by a cylinder instead of the amount). The rhizome depth is a columnar shape where the rhizomes 32 are densely packed. The height of the object, the depth of the root 33 indicates the depth from the deepest part of the rhizome 32 to the deepest part where the roots 33 are distributed, and the deepest root length is the length of the longest root tip 34 from the ground. Indicates the length.

[0025]

[Table 3]

The larger the numerical value of the soil holding amount, the larger the amount of soil that can be held. As a result, "Miyako" had the highest soil retention, followed by Kouraishiba. Moreover, despite the fact that the root distribution at the bottom of the rhizome does not change, when comparing the rhizome depth, "Miyako" is 3
There were about twice as many species. This suggests that the depth of rhizome distribution has the greatest effect on soil retention.

In order to examine "Miyako" and "Noshiba" in detail, in Test 4, planting was performed in mountain sand, taken out one year later, and the results are shown in Table 4. The rhizome depth of “Miyako” was 5.8 ± 0.57 cm on average, which was about twice that of the control Noshiba.

[0028]

[Table 4]

<D> Planting on the slope In order to actually examine the planting on the slope, in Test 5, as a strain having a low covering growth amount but a large amount of soil retention, it is a line that has a large amount of soil retention. Three systems, "Hayato" and "Miyako", which are superior in both, were carried out on the slope of the irrigation canal, and the results are shown in Table 5. All three types of turf were planted with a joint coverage of 70% at the slope. In addition, the planting was performed in the slope direction of the slope so that the joints (5 to 6 cm) were aligned so that soil runoff easily occurred, and the planting was further performed during the plum season.

In Table 5, the survival of turf seedlings indicates the percentage of turf seedlings that maintain a green leaf area of 50% or more one month after planting. The numerical values were the average of 4 test sites per species, and the least significant difference LSD (5%) was 18.6.
One test site is 2 m ² . The coverage is a green leaf covering area index 4 months after planting, and is shown as 0: bare land to 10: completed. The numerical values indicate the average value of three test sites per species. The completion period indicates the period during which the plantation is completely covered with turf. Erosion is the degree of occurrence of erosion 4 months after planting, and is shown as 1: slight to 9: severe. The protection effect is determined from the protection effect = A-B-C, assuming that the slope protection effect at the time of covering the entire surface is 100. A = 10 × coverage, B = planting amount × (100−root ratio) / 200, C =
(100-planting amount) / 2 × erosion rate / 10 × ｛1 + Σ2
^{-(T-4) / 4} ｝. Here, T = completion period. The completion period T indicates the number of months and is 4 or more. Σ in the equation is the sum of the risk of erosion occurring during the completion period T.

[0031]

[Table 5]

[0032] In the rice cultivars, the survival of turf seedlings is the worst.
Time was required for coating. In particular, as for the seagrassgrass, the joint became a water diameter and the rill erosion occurred. As a result, a depression was observed four months after planting. In Hayato, no serious soil erosion was observed, but the creeping stalks at the joint did not progress, and it took time to complete the covering. On the other hand, in the case of Miyako, the covering was completed four months after planting, and the erosion damage seen during that period was minimal, and the protection effect of the planting was the highest. This indicated that the difference in joint coverage between "Hayato" and "Miyako", which have the same covering growth property, was affected by the distribution depth of the rhizome.

Therefore, (1) the evaluation traits used for the selection of Nihon Shiba strains were appropriate, (2) the superiority of the cover growth had the greatest effect on slope protection, and (3) the soil retention of the root system It was suggested that they also have a complementary effect. In other words, greening slopes with Japanese turf like "Hayato" can be expected to have a relatively high protection effect, but the risk of erosion is required for at least one year before the covering is completed, so it is necessary to plant an appropriate amount. . In addition, it was thought that the cover growth ability was also an index of the vigor of turf seedlings, as seen in the example of rice brassicae.

<E> Planting of paddy field ridge method The final selection of "Miyako" was carried out, and a study was conducted on four types of planting methods using a paddy field ridge with a relatively short slope and varying the amount of seedlings planted. Table 6 shows the results. The planting amount is represented by the ratio of the area of the turf seedling to the area of the completed plant. As for the planting shape, joints and checkers use grass seedlings of about 30 cm square, and the roll is 36
Rolled lawn seedlings of cm × 140 cm were opened and planted. The paddy ridges have slopes on both sides of the top, so joints and checkers were placed on the top and both sides of the planting site, and rolls were placed only on the top. The survival of turf seedlings indicates the percentage of turf seedlings that maintain a green leaf area of 50% or more one month after planting, and the numerical values indicate the average value of four test sites per species. The coverage is a green leaf covering area index 4 months after planting, and is shown as 0: bare land to 10: completed. The numerical values indicate the average value of three test sites per species. The completion period indicates the period until the planting site is completely covered with turf. The degree of erosion is the degree of erosion occurring four months after planting, and is shown as 1: slight to 9: severe. The walking ability at the top indicates the level of safety with respect to walking at the top four months after planting, and is shown in five stages from 1: poor to 5: good. As for the planting effect, assuming that the protective effect at the time of covering the entire surface is 100, and further taking into account the walking property at the top, the planting effect = A-B-C +
Calculate from D. A = 10 × coverage, B = planting amount ×
(100-survival rate) / 200, C = (100-planting amount)
/ 2 × erosion rate / 10 × {1+ {2- ^{(T-4) / 4} }, D = top area (38.5%) × top coverage / 10 × walkability /
5, T = completion period. The completion period T in the equation is
Indicates the number of months and is 4 or more. Σ in the equation is the sum of the risk of erosion occurring during the completion period T.

[0035]

[Table 6]

As a result, almost complete jointing (80%
(Planting) produces a very high planting effect, followed by checkerboarding (50% planting) and top-rolling (25% planting)
Was a good result. In particular, the roll-covering was able to reduce the amount of planted seedlings by half compared to the checkered-covering, although the time required for covering was the same, and the occurrence of erosion was light enough to cause no problem. However, further reductions in planting lengthened the time required for covering and increased the occurrence of erosion, thus increasing the risk of erosion damage. Therefore, the planting amount was considered to be about 25%. On the other hand, when planting turf seedlings, planting only the top, which is almost equivalent to the amount of planting, can prevent the collapse of the shoulder, compared to planting the entire ridge (top and slope). There was no undulation due to the lawn seedlings, and the efficiency of planting was high. In particular,
The absence of ups and downs due to lawn seedlings enhances the safety of top end work because of excellent walking at the top end. In addition, a roll-shaped lawn seedling (width 36 cm × length 140 cm = 0.5 m ² ) corresponding to 4 to 5 lawn seedlings can be used for top-end planting. Even higher.

As described above, the characteristics of Japanese turf such as "Miyako", which is excellent in overgrowth and excellent in soil retention due to its deep rhizome distribution, are necessary for slope planting. Furthermore, on relatively short slopes such as levees, planting the top of such Japanese turf is effective.

[0038]

According to the present invention, the following effects can be obtained. <B> Since the lawn seedlings are not planted on the slope only at the top, the planting work is simplified and does not involve danger. <B> Since the lawn seedlings are planted on the top, the collapse of the shoulder can be prevented, and when the top is a working walkway, the top is free of undulations and work can be done safely. . <C> It is possible to save material costs by reducing the amount of planted seedlings, reduce the amount of planting work, and save labor costs due to high workability. <D> The slope is covered in about one year after planting, although it varies depending on the planting time. <E> Since the plant is not planted directly on the slope, there is no need for a support such as a skewer, and since the turf is closely attached to the surface, it is not easily damaged by birds. <F> Cover-planting at the top will reduce scattering of raindrops and make it difficult for water to adhere to the slope. <G> Japanese turf vegetation can reduce the occurrence of tall weeds, save labor for management work, and provide an aesthetic appearance. <H> When applied to paddy field ridges, when the covering is completed, the occurrence of weeds, which are the source of pests, can be reduced, and labor for weed management can be reduced. <I> When the coating is completed, erosion due to waves and rainfall and the invasion of small animals such as rats will be reduced, and labor for water leakage countermeasures can be saved.

[Brief description of the drawings]

FIG. 1 is a slope vegetation map of the present invention.

FIG. 2 is a cylindrical view of a lawn taken out with a hole cutter.

FIG. 3 is a view of FIG. 2 with soil removed;

Claims (4)

[Claims] 1. A method of greening a slope having a top, comprising: planting turf seedlings only at the top, growing the turf to the slope, and greening the slope.
How to green the slope. 2. A slope revegetation turf for revegetating a slope, characterized in that it has excellent coverage and multiplication. 3. A slope greening turf for greening a slope, which is excellent in soil retention. 4. The slope greening turf according to claim 2 or 3, wherein the turf has a variety name “Miyako”.