Vegetation restoration method

Abstract

To provide a vegetation restoration method capable of maintaining more substrates stably for a long period of time and contributing to improve construction efficiency.SOLUTION: A vegetation restoration method in accordance with the present invention includes arranging a vegetation restoration device D, which includes at least one embracing wire 4A embracing a long-shaped substrate flowing-out prevention member 2 in a spiral state as a wire member 4 configuring a wire mesh 1. The embracing wire 4A comprises an upper wire part 4a projected upward in a curved state and a lower wire part 4b projected downward in a curbed state.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vegetation restoration method suitable for restoring vegetation on, for example, slopes and the like. [Background technology]

[0002] A commonly used vegetation restoration method involves laying wire mesh on a slope and spraying on it soil and vegetation substrate to allow plants to grow. The slope protection device described in Patent Document 1 employs wire mesh that is thicker than a generally flat, diamond-shaped wire mesh to prevent the soil and substrate from being washed away by rainfall or other factors, and a substrate washout prevention member (fiber rope) is threaded and stretched through the interior space of the wire mesh. To further enhance the effectiveness of preventing substrate washout, instead of the conventional spraying method, the present applicant has proposed a slope greening structure (Patent Document 2) in which vegetation bags filled with substrate are placed in the grooves of the thick wire mesh and held in place by a mesh body, and substrate washout prevention members (stoppers made of linear bundles of palm fiber or the like) are arranged in a contoured pattern to prevent the vegetation bags from slipping and the substrate from being washed away. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Microfilm of Utility Model Application No. 58-37800 (Utility Model Application No. 59-144050) [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-336193 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in both the slope protection device of Patent Document 1 and the slope greening structure of Patent Document 2, the substrate flow prevention member (a fiber rope in Patent Document 1 and a stopper in Patent Document 2) is inserted loosely into the internal space of the thick wire mesh (the cross-sectional area of ​​the substrate flow prevention member is one size smaller than the cross-sectional area of ​​the internal space of the wire mesh). As a result, depending on the uneven shape of the ground and the arrangement of the substrate flow prevention member, there is a risk that the substrate flow prevention member may float significantly above the ground, thereby compromising the substrate flow prevention effect. Furthermore, as a result, the substrate flow prevention member is prone to shifting from its fixed position relative to the wire mesh. This shift causes the substrate flow prevention member to move out of one side of the wire mesh, creating a gap in the wire mesh where no substrate flow prevention member is present. This means that the desired substrate flow prevention effect will not be achieved in at least that area, and additional work will be required to correct the shift, which creates a corresponding problem of reduced construction efficiency.

[0005] The present invention has been made with the above points in mind, and its object is to provide a vegetation restoration method that can stably maintain a larger number of substrates for a long period of time and also contributes to improving construction efficiency. [Means for solving the problem]

[0006] In order to achieve the above object, the present invention provides a vegetation restoration method in which a vegetation restoration device comprising a wire mesh and a long substrate washaway prevention member is arranged on a slope together with a substrate containing at least one of seeds, vegetation base material, fertilizer, and erosion prevention material, and the wire mesh has a three-dimensional thickness formed by engaging a plurality of wire rods bent in a substantially spiral shape with each other so that the spiral axes of the wire rods are substantially parallel to each other, and each wire rod is configured so that an upper line portion curved in an upward convex shape and a lower line portion curved in a downward convex shape are alternately connected to form a substantially spiral shape, and the wire rods in which the substrate washaway prevention member is housed are arranged so that the substrate washaway prevention member is attached to the wire rod by the screw. The wire is designed to be an embracing member that embraces in a spiral shape, and this embracing is such that the substrate flow prevention member contacts each of the upper line portion and the lower line portion that are repeatedly connected to the wire, and the embracing wire has an upper line portion that is curved convex upward and a lower line portion that is curved convex downward, and the substrate flow prevention member has a belt-like shape with a substantially rectangular cross section, and the upper line portion and the lower line portion contact or are embedded in the corners of the substrate flow prevention member, and the vegetation restoration device with the substrate flow prevention member held on the deployed wire mesh is fixed to the slope with anchor pins, and at this time the substrate flow prevention member is arranged so as to follow the contour lines of the slope, and a layer of substrate is formed to cover the vegetation restoration device. The base material flow-out prevention member is made of natural fibers such as palm. (Claim 1).

[0007]

[0008] In the above-mentioned vegetation restoration method, the upper line portion and the lower line portion may have the same curvature (Claim 2). The embracing wire may be configured to describe a flattened ellipse whose height is smaller than its width when viewed from one end of its spiral axis (Claim 3).

[0009] In the above-mentioned vegetation restoration method, the thickness of the substrate flow-away prevention member may be smaller than its width (claim 4).

[0010] [Effects of the Invention]

[0011] The present invention provides a vegetation restoration method that can stably maintain a larger number of substrates for a long period of time and also contributes to improving construction efficiency.

[0012] In other words, in the vegetation restoration method of the invention according to each claim of the present application, the embracing wires that make up the wire mesh helically embrace the base material flow prevention members, so that when the wire mesh is aligned with the unevenness of the natural ground, the base material flow prevention members also follow the unevenness of the natural ground, thereby enhancing the base material flow prevention effect of the base material flow prevention members. Moreover, in the vegetation restoration method of the present invention, the wire mesh and the base material flow prevention members are integrated by the above-mentioned embracing, making it less likely that the base material flow prevention members will accidentally shift from their fixed position relative to the wire mesh, thereby eliminating the need for work such as returning the base material flow prevention members to their fixed position, and improving construction efficiency.

[0013] In the vegetation restoration method of the invention of claim 1, the lower line of the embracing wire is curved downward to convexly, thereby increasing the holding power of the substrate. In other words, the holding power of the substrate is affected not only by the shape of the wire mesh and the presence or absence of a substrate wash-off prevention member, but also by the frictional resistance of the substrate itself against the surface of the construction area. In this method, the contact area between the lower line of the embracing wire and the surface of the construction area is reduced, while the substrate can be held in the gap below the lower line, thereby increasing the frictional resistance of the substrate against the surface of the construction area and, as a result, improving the effectiveness of preventing the substrate from washing away.

[0014] In addition, in this construction method, the underline portion of the embracing wire is curved downward in a convex shape, so the underline portion is less likely to prevent the base material flow prevention member placed on top of it from contacting the surface of the construction area, thereby increasing the effectiveness of the base material flow prevention member in preventing the base material from flowing away.

[0015] In addition, in the vegetation restoration method of the invention of claim 1, the upper line portion of the embracing wire is curved in an upward convex shape, so that the width of the upper line portion narrows toward the upper side, and if it is covered with a base material so that at least the entire upper line portion is not exposed, for example, when the base material is eroded or washed away by a sudden downpour or typhoon, the amount of the upper line portion exposed to the surface of the base material increases as this progresses, and the ability to capture airborne seeds, etc. is strengthened, preventing a significant impairment of the vegetation restoration ability.

[0016] In the vegetation restoration method of the invention according to claim 2, productivity is improved by standardizing the shapes of the upper and lower lines, and the wire mesh can be installed in a reversible manner by eliminating the need for a front and back.

[0017] In the vegetation restoration method of the invention according to claim 1, by making the substrate flow prevention member approximately rectangular in cross section, it is possible to eliminate the front and back (top and bottom) of the substrate flow prevention member and make it possible to insert it reversibly into the wire mesh, and it is also possible to make the substrate flow prevention member more easily come into surface contact with the ground, thereby improving the effectiveness of preventing the substrate flow. Moreover, for example, when the upper and lower lines of the embracing wire are each curved as in claim 1, the substrate flow prevention member effectively fills the space surrounded by the upper and lower lines, and the upper and lower lines come into contact with or sink into the corners of the substrate flow prevention member, making it difficult for the substrate flow prevention member to shift position or come off the wire mesh, and it is also possible to securely hold the substrate flow prevention member to the wire mesh without using special fastening devices.

[0018] Claim Item 1 In the vegetation restoration method of the present invention, by using natural fibers such as palm fibers for the substrate washaway prevention material, it is possible to improve the water retention capacity of the material and it is also expected that the material will have a fertilizer effect due to biodegradation. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1A is an explanatory diagram showing a schematic configuration of a vegetation restoration method according to one embodiment of the present invention, and FIG. 1B is a plan view of a vegetation restoration device used in the vegetation restoration method. [Figure 2] 1A is a partially enlarged perspective view of the vegetation restoration device, and FIG. 1B is a cross-sectional view of the wire mesh of the vegetation restoration device. [Figure 3] 1 is a graph showing the results of an erosion resistance confirmation test conducted on a product that has undergone the vegetation restoration method and a conventional product, with the vertical axis representing the thickness of the substrate and the horizontal axis representing the elapsed time from the start of the test. DETAILED DESCRIPTION OF THE INVENTION

[0020] An embodiment of the present invention will be described below.

[0021] The vegetation restoration method in this example involves placing a vegetation restoration device D equipped with a wire mesh 1 and a substrate washaway prevention member 2 together with a substrate 3 in the construction area R (in this example, a slope), as shown in Figure 1(A).

[0022] As shown in Figure 2(A), the wire mesh 1 is a diamond-shaped wire mesh (wire lath) with a three-dimensional thickness, which is made by engaging multiple wires 4 bent in an approximately spiral shape with each other so that the spiral axes of the wires 4 are approximately parallel to each other.

[0023] The wire mesh 1 in this example has a width W (see FIG. 1(B)) of approximately 2000 mm, a length L (see FIG. 1(B)) of approximately 10000 mm, a mesh size of approximately 56 mm, and a thickness (height) T (see FIG. 2(B)) of approximately 16 mm. The wire 4 is made of, for example, zinc-plated iron wire and may be of any thickness depending on the required strength, etc. However, a thickness of less than 1 mm will result in insufficient strength as a wire mesh, and a thickness of more than 10 mm will result in the resulting wire mesh being heavy and difficult to install, so a thickness of 1 to 10 mm is preferred. Here, both ends of the wire 4 are knuckled, but they may also be processed by other appropriate processes such as twisting.

[0024] As shown in the enlarged view in Figure 1(A) and Figures 2(A) and (B), each wire 4 is configured so that upwardly convex curved upper line portions 4a and downwardly convex curved lower line portions 4b are alternately connected to form a roughly spiral shape, and as shown in particular in Figures 1(A) and 2(B), when viewed from one end in the spiral axis direction, it is configured so that it forms a flattened ellipse whose height is smaller than its width (the longitudinal cross-sectional shape is a flattened ellipse).

[0025] As shown in Figure 1(B), the base material flow prevention member 2 is long and is housed in a portion of the wire 4 of the wire mesh 1 so that its spiral axis passes through it. Such a base material flow prevention member 2 is preferably made of fibers such as coconut fiber, straw, or palm hair, which are held in the shape of a nonwoven fabric by chemical bonding, thermal bonding, needle punching, or other methods. However, the present invention is not limited to this, and the base material flow prevention member 2 may also be made by cutting a mat (such as a general-purpose mat) made of coconut fiber into a long, thin belt shape.

[0026] Furthermore, in this example, the substrate flow prevention member 2 is belt-shaped (strip-shaped) with a length that is approximately the same as the width of the wire mesh 1 (approximately 2000 mm) (see FIG. 1(B)), and the cross section perpendicular to the longitudinal direction is rectangular with dimensions of approximately 30 mm (width) x approximately 10 mm (thickness) (see FIG. 1(A)). That is, in accordance with the flattened ellipse shape of each wire 4 as described above, the thickness of the substrate flow prevention member 2 is smaller than its width (for example, the thickness is approximately half the width or less). The thickness of the substrate flow prevention member 2 can be changed as appropriate depending on the material, properties, etc. For example, if the substrate flow prevention member 2 is a belt-shaped member made of palm fiber and the thickness T of the wire mesh is 16 mm, the thickness can be approximately 12 to 13 mm.

[0027] In order to stabilize and ensure the retention of the base material flow prevention member 2 by the wire mesh 1, in this example, the wire 4 in which the base material flow prevention member 2 is housed is configured to helically embrace the base material flow prevention member 2 (the base material flow prevention member 2 is in contact with each of the repeated upper line portions 4a and lower line portions 4b of the wire 4). This makes it less likely that the base material flow prevention member 2 will fall off the wire mesh 1 even if it deteriorates over time, making it easier to maintain its function over a long period of time. Below, the wire 4 that helically embraces the base material flow prevention member 2 housed therein may be referred to as the embracing wire 4A to distinguish it from the other wires 4 that do not house the base material flow prevention member 2, but in this example, the shapes of each wire 4 (the embracing wire 4A and the other wires 4) are the same.

[0028] The substrate 3 includes at least one of seeds, vegetation base material, fertilizer, and erosion prevention material.

[0029] Next, the construction procedure of the vegetation restoration method of this example will be explained.

[0030] (1) First, as shown in Figure 1(A), a wire mesh 1 is laid in the construction area R, which is a slope, and a substrate flow prevention member 2 is held by the wire mesh 1 (embracing wire 4A), and both 1 and 2 are fixed to the construction area R with anchor pins 5. At this time, the substrate flow prevention member 2 is positioned so as to follow the contour lines of the construction area R. This results in the vegetation restoration device D being laid (installed) in the construction area R.

[0031] In this example, a base material escape prevention member 2 is inserted into the inner space at one end of the embracing wire 4A of the wire mesh 1, which has been rolled up in advance, and an anchor pin 5 is driven into this base material escape prevention member 2 to fix it together with the wire mesh 1 in the construction area R. After that, the wire mesh 1 is unfolded toward the foot of the slope, and the base material escape prevention member 2 is inserted into the embracing wire 4A of the wire mesh 1 at regular intervals (for example, 500 mm) from the top of the slope toward the bottom of the slope, while being fixed with the anchor pins 5. Then, to accommodate the unfolding work of the wire mesh 1 as described above, at least some of the anchor pins 5 driven into the part located closest to the top of the slope (upper side) are slightly larger than the other anchor pins 5, allowing for stronger fixation.

[0032] In addition, if the wire mesh 1 with the substrate flow prevention members 2 inserted at regular intervals can be rolled up, the substrate flow prevention members 2 may be pre-inserted (attached) to the wire mesh 1. Even if the wire mesh 1 with the substrate flow prevention members 2 inserted cannot be rolled up, the substrate flow prevention members 2 may be pre-inserted (attached) to the wire mesh 1 if, for example, the wire mesh 1 is to be transported in an unfolded state.

[0033] (2) A layer of the base material 3 is formed by spraying or scattering the base material 3 so as to cover the vegetation restoration device D (wire mesh 1 and base material washaway prevention member 2) laid in the construction area R.

[0034] The vegetation restoration method of this example is completed through the above steps (1) and (2).

[0035] In the vegetation restoration method of this example, the embracing wires 4A that make up the wire mesh 1 helically embrace the base material flow prevention members 2, so that if the wire mesh 1 is aligned with the unevenness of the ground, the base material flow prevention members 2 will also follow the unevenness of the ground, thereby improving the base material flow prevention effect of the base material flow prevention members 2. Moreover, in the vegetation restoration method of this example, the wire mesh 1 and the base material flow prevention members 2 are integrated by the above-mentioned embracing, and the base material flow prevention members 2 are less likely to accidentally shift from their fixed position relative to the wire mesh 1, so that work such as returning the base material flow prevention members 2 to their fixed position is unnecessary, and construction efficiency is also improved.

[0036] Furthermore, in the vegetation restoration method of this example, basically only wire mesh 1, substrate washaway prevention member 2, substrate 3, and anchor pin 5 are used, and the number of required parts and labor is small, so it is extremely easy to reduce the cost of construction.

[0037] Furthermore, in the vegetation restoration method of this example, the long substrate flow prevention member 2 is arranged so as to roughly follow the contour lines and is fixed together with the wire mesh 1 by anchor pins 5 so that it is in contact with the surface of the construction area R, so that the substrate flow prevention member 2 acts as a cushioning material and the wire mesh 1 as a whole is able to easily fit the unevenness of the surface of the construction area R.

[0038] In the vegetation restoration method of this example, the underline 4b of each wire 4, including the embracing wire 4A, is curved downward to convexly extend, thereby increasing the holding power of the substrate 3. In other words, the holding power of the substrate 3 is affected not only by the shape of the wire mesh 1 and the presence or absence of the substrate washaway prevention member 2, but also by the frictional resistance of the substrate 3 itself against the surface of the construction area R. In this regard, the method of this example reduces the contact area between the underline 4b of each wire 4A and the surface of the construction area R, while also allowing the substrate 3 to be held in the gap below the underline 4b, thereby increasing the frictional resistance of the substrate 3 against the surface of the construction area R and, as a result, improving the effectiveness of preventing the substrate 3 from washing away.

[0039] In addition, in this construction method, the underline portion 4b of each wire 4, including the embracing wire 4A, has a downwardly convex curved shape, so the underline portion 4b is less likely to prevent the base material flow prevention member 2 placed on top of it from contacting the surface of the construction area R, thereby increasing the effectiveness of the base material flow prevention member 2 in preventing the base material 3 from flowing away.

[0040] In addition, in the vegetation restoration method of this example, the upper line portion 4a of each wire 4, including the embracing wire 4A, is made convexly curved upward, so that the width of the upper line portion 4a narrows toward the upper side.If the upper line portion 4a is covered with the base material 3 so that at least the entire upper line portion 4a is not exposed, then, for example, if erosion or washing away of the base material 3 progresses due to heavy rain or typhoons, the amount of upper line portion 4a exposed to the surface of the base material 3 increases as this progresses, and the ability to capture flying seeds, etc. is strengthened, preventing a significant impairment of the vegetation restoration ability.

[0041] Furthermore, in the vegetation restoration method of this example, the curvature of the upper line portion 4a and the lower line portion 4b of each wire 4 is made the same, and their shapes are made common, which improves productivity and also makes it possible to eliminate the front and back of the wire mesh 1, making it possible to carry out reversible construction.

[0042] Furthermore, in the vegetation restoration method of this example, by making the substrate washaway prevention member 2 approximately rectangular in cross section, the substrate washaway prevention member 2 has no front or back (top and bottom), making it reversible to insert into the wire mesh 1, and it also makes it easier to bring the substrate washaway prevention member 2 into surface contact with the ground, improving the effectiveness of preventing the washaway of the substrate 3. Moreover, because the upper line portion 4a and the lower line portion 4b of each wire 4 including the embracing wire 4A are each curved, the substrate washaway prevention member 2 effectively fills the space surrounded by the upper line portion 4a and the lower line portion 4b, and the upper line portion 4a and the lower line portion 4b contact or sink into the corners of the substrate washaway prevention member 2, making it difficult for the substrate washaway prevention member 2 to shift position or come off the wire mesh 1, and it is also possible to securely hold the substrate washaway prevention member 2 to the wire mesh 1 without using any special fastening devices.

[0043] Furthermore, in the vegetation restoration method of this example, by using natural fibers such as palm for the substrate washaway prevention member 2, its water retention capacity can be improved, and it is also expected that it will have a fertilizer effect due to biodegradation.

[0044] The following describes the details and results of the erosion resistance confirmation test conducted to compare the vegetation restoration method of this example with conventional vegetation restoration methods.

[0045] First, as an embodiment of the present invention (this example), a vegetation restoration device D was prepared, in which substrate flow prevention members 2 were attached at regular intervals to a wire mesh 1, and as a conventional embodiment, a generally flat diamond-shaped wire mesh (lath wire mesh) was prepared.

[0046] Two test frames, each consisting of a flat, roughly rectangular box with the top removed, were filled with compacted decomposed granite soil to a height of 5 cm. One test frame was fitted with the vegetation restoration device D, an embodiment of the present invention, and the other with a conventional wire mesh. A 3 cm thick growth substrate (substrate 3) was sprayed onto each frame. Each test frame was then placed in a rainfall test apparatus with a 1:1.0 (45°) gradient. Piano wire was stretched across the surface of each test frame, dividing it into 16 4x4 grids. The average thickness of substrate 3 at nine intersections was measured and calculated every hour for six hours at an hourly rainfall rate of 100 mm / hour. The results are shown in Table 1 and Figure 3.

[0047] [Table 1]

[0048] As is clear from the results shown in Table 1 and FIG. 3, when the product of the present invention is used, the thickness of the substrate 3 is greater and the corrosion prevention effect is higher than when the conventional product is used.

[0049] It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the following modifications can be mentioned.

[0050] The base material 3 may be topsoil (topsoil seed bank, topsoil mixed with buried seeds) collected from the construction area R or its surrounding area.In this case, the vegetation restoration method of this example can be implemented as a forest topsoil utilization work that restores vegetation in harmony with the surrounding environment.

[0051] In the above embodiment, the wire mesh 1 is completely covered with the base material 3, but this is not limiting and at least a portion of the wire mesh 1 may not be covered with the base material 3. In this case, the exposed portion of the wire mesh 1 on the surface side of the base material 3 makes it easier to capture airborne seeds, fallen leaves, etc., making the vegetation restoration method of this example feasible as a natural invasion promotion method that excels in restoring vegetation in harmony with the surrounding environment. In addition, in this case, the amount of base material 3 used can be reduced, which also contributes to reducing the labor and costs required for construction.

[0052] Here, when the wire mesh 1 is covered with the base material 3 so that only the upper part (upper line portion 4a) of the wire mesh 1 is exposed, this exposed part (upper line portion 4a) extends in a direction oblique to the contour lines in the construction area R, which is the slope, and multiple exposed parts (upper line portions 4a) are arranged in a roughly staggered pattern.

[0053] The material of the substrate flow-out prevention member 2 may be a shape-retaining material obtained by solidifying fibers with latex, resin, etc., or a thick, hard nonwoven fabric, etc. In any case, it is desirable that the substrate flow-out prevention member 2 has strength in the thickness direction to the extent that it will not be crushed by the weight of the substrate 3 sprayed on top of it.

[0054] In the above embodiment, the embracing wire 4A and the other wires 4 have the same shape, but they may have different shapes.

[0055] It goes without saying that the above modifications may be combined as appropriate. [Explanation of symbols]

[0056] 1 wire mesh 2 Base material flow prevention material 3 Base material 4 wire rod 4A Enclosed Wire 4a Overlined part 4b Underlined part 5 anchor pins D Vegetation restoration device L length R construction area T Wire mesh thickness W Wire mesh width

Claims

1. A vegetation restoration method in which a vegetation restoration device including a wire mesh and a long substrate washaway prevention member is placed on a slope together with a substrate including at least one of seeds, vegetation base material, fertilizer, and erosion prevention material, The wire mesh has a three-dimensional thickness and is formed by engaging a plurality of wire rods bent in a generally spiral shape with each other so that the spiral axes of the wire rods are generally parallel to each other, and each wire rod is configured so that an upper line portion curved in a convex shape upward and a lower line portion curved in a convex shape downward are alternately connected to form a generally spiral shape, The wire in which the base material flow prevention member is housed is configured to be an embracing member that helically embraces the base material flow prevention member, and this embracing is such that the base material flow prevention member contacts each of the upper line portion and the lower line portion that are repeatedly connected to the wire, the embracing wire has an upper line portion that is curved convexly upward and a lower line portion that is curved convexly downward, the base material flow prevention member has a belt shape with a substantially rectangular cross section, and the upper line portion and the lower line portion are in contact with or sink into corners of the base material flow prevention member, The vegetation restoration device, with the substrate washaway prevention members held on the deployed wire mesh, is fixed to the slope with anchor pins, and at this time, the substrate washaway prevention members are arranged along the contour lines of the slope, and a layer of substrate is formed to cover the vegetation restoration device; A vegetation restoration method in which the base material washaway prevention member is made of natural fibers such as palm.

2. The vegetation restoration method according to claim 1 , wherein the upper line portion and the lower line portion have the same curvature.

3. 3. The vegetation restoration method according to claim 2, wherein the embracing wire is configured to describe a flattened ellipse whose height is smaller than its width when viewed from one end of the spiral axis direction.

4. 4. The vegetation restoration method according to claim 1, wherein the thickness of the substrate flow prevention member is smaller than its width.

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