JP7165941B2 - Method for constructing a solid earth embankment to prevent soil erosion - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method and a construction apparatus for constructing a solid earth embankment in a soil layer for suppressing soil runoff.

In recent years, due to the frequent occurrence of torrential rains, soil erosion, in which surface soil is washed away by surface water, has frequently occurred in sloped farmlands. As a result, agricultural production activities are hindered and the water environment of local public water bodies is adversely affected. Farmers implement soil erosion control measures to control the erosion of fertile topsoil and permanently maintain productivity. In addition, soil erosion control is necessary as a water quality conservation measure for public water areas that serve as regional water sources, and as an environmental conservation measure for water areas such as rivers and seas.

Soil erosion control measures include the no-tillage cultivation method in which crops are cultivated in a non-tilled state, the contour cultivation method in which plows and crop ridges are arranged in the contour direction, and the soil level by planting crops and green manure. Covering measures to prevent the field from becoming bare ground, a water collection method by digging trenches in the field to prevent water from flowing directly in the direction of the slope, a vegetation buffer zone measure to filter the sediment that flows out to the outside of the field, and There are measures such as setting up a settling basin that settles the earth and sand. However, there are drawbacks in terms of the time and effort required to respond, and the degree of effect manifestation.

Specific examples of such measures for suppressing soil runoff are found in Patent Documents 1 to 4 and Non-Patent Documents 1 to 4.
Patent Literature 1 discloses a soil erosion prevention construction method in which a material containing mycelium added to an organic material is sprayed on the soil surface to constrain the soil by propagating the mycelium. Patent Literature 2 discloses a method for preventing soil runoff in which the surface of soil is covered with a part of a plant body mainly composed of parenchyma cells. Patent Document 3 discloses spraying a soil erosion inhibitor containing a water-based resin emulsion and a water-soluble polymer, but the spraying of the material loses its effectiveness by tilling, and cannot be used for a long period of time. Patent Literature 4 discloses a method of forcibly mitigating the effects of rainfall and freeze-thaw using sheets, but sheets interfere with plowing work for cultivating crops in farmland. These conventional techniques are difficult to perform each time from the viewpoint of cost and labor.

Non-Patent Document 1 includes mitigation of field gradients, installation of water receiving channels and drainage channels, installation of underdrains as civil engineering methods, installation of ridges as agricultural land management, contour cultivation, green belts, etc., mulching and cover crops as plowing and farming measures. , minimum tillage (less or no tillage), crop rotation, intercropping, and organic matter input. In actual upland farming areas, land gradients are eased and culverts and drainage canals are constructed as part of infrastructure development projects, but this is not applicable to all farmlands due to the high cost burden. Even if these improvements are made, they do not constitute a drastic countermeasure against soil erosion. Also, the effects of crop rotation and organic matter input are limited. Furthermore, contour cultivation can be carried out on very gentle slopes, but cannot be carried out on steep slopes because mechanical work is impossible. Intercropping is effective, but there are times when the ground surface cannot be covered with vegetation and the ground becomes bare due to the crop rotation system. Greenbelt, mulching and cover cropping are the most effective, but often difficult to implement due to profitability, cost and work system of crop rotation. It is extremely difficult to introduce minimum tillage (less tillage, no tillage) due to the problem of overgrown weeds in Japan, which has a humid climate.

As a practical countermeasure in farming, Non-Patent Document 3 discloses a countermeasure for preventing red soil runoff in farming by introducing grassy zones and buckwheat cultivation. It is effective for introducing buckwheat cultivation and mulch installation using its residue, but it is difficult to introduce in large-scale agricultural areas because it takes time and effort to implement. Non-Patent Document 4 discloses the suppression of soil runoff in large-scale sloping farm fields by introducing a terrace drainage channel, etc., but the terrace drainage channel causes collapsed land in agriculture, hinders farm work, and causes weeds to grow and grow. , there is a problem that the effect disappears until it is rebuilt after tillage.

JP 2004-360206 A (Soil erosion prevention method) JP 2004-350547 A (soil erosion prevention method) JP 2016-204290 A (soil erosion inhibitor with excellent freeze-thaw stability) JP-A-10-60901 (sheet-like material for preventing soil erosion)

"Municipal government measures and farmers' responses to prevent red soil runoff from farmland in Okinawa Prefecture" http://www.jstage.jst.go.jp/article/arp1982/21/3/21_3_232/_pdf Issued in March 2011 "To Protect Farmland from Heavy Rain" (Eastern Arable Land Branch Office, Okhotsk General Promotion Bureau) http://www.okhotsk.pref.hokkaido.lg.jp/file.jsp?id=225105 Issued in September 2007, "Measures to Prevent Red Soil Runoff for Farming by Introducing Grassy Zones and Buckwheat Cultivation" https://www.jstage.jst.go.jp/article/jjsidre2007/75/9/75_9_817/_pdf/-char/ja "Soil erosion control in large-scale sloping farm fields by introduction of terrace drainage channels" http://www.naro.affrc.go.jp/project/results/laboratory/nilgs/2015/nilgs15_s34.html

The problem of soil erosion control is that the ground surface becomes bare during the period from plowing and after seeding to early growth, after harvesting, and before and after winter, and soil erosion occurs during this period. No technique has been proposed to cope with this period.

In view of the above situation, an object of the present invention is to provide a method for suppressing soil erosion in farmland that can solve the above-described problems of the prior art, and a construction apparatus used therefor.

In order to achieve the above objects, the present invention provides the following configurations.
(1) One aspect of the present invention is a method of constructing a tight earth embankment in a soil layer to suppress soil erosion in farmland, comprising:
In one plowing row, while advancing the tractor vehicle, plowing the compact uncultivated soil to a predetermined plowing depth with a cultivator attached to the tractor vehicle;
At a predetermined position in the forward direction in the one tillage row, the cultivator is raised above the ground surface, and in this state, the traction vehicle is advanced by a predetermined distance in the one tillage row. By lowering the cultivator to the tillage depth and restarting forward tillage in the one tillage row, a solid earth embankment is constructed between two tillage parts in the one tillage row. death,
The firm and dense earth embankment of the untilled portion has a length corresponding to the advance distance while the tiller is raised and a width of the tiller, and is made of firm and dense untilled soil. do.
(2) Another aspect of the present invention is a method of constructing a tight earth embankment in a soil layer for suppressing soil erosion in farmland, comprising:
Cultivating firm uncultivated soil to a predetermined plowing depth with a cultivator attached to the towing vehicle while advancing the towing vehicle,
At a predetermined position in the forward direction, the cultivator is raised to a depth shallower than the tillage depth, and in this state, the tractor is advanced by a predetermined distance to cultivate, and then the cultivator is lowered to the tillage depth again. By cultivating the land, constructing a tight earth embankment of the upper layer of shallow tillage and the lower layer of uncultivated soil,
The tight-dense earth bank of the uncultivated soil in the lower layer has a length corresponding to a forward movement distance while the cultivator is raised and a width of the cultivator.
(3) In any one of the above aspects, the compact earth embankment of the untilled portion or the compact earth embankment of the uncultivated soil of the lower layer is constructed on a slope.
(4) In any of the above aspects, subsoil crushing or a soil layer is performed using a tiller before or after construction of the compact earth embankment of the untilled portion or the solid earth embankment of the uncultivated soil in the lower layer. It is characterized by constructing a subsoil crushing ditch with high water permeability by crushing solid uncultivated soil to a depth deeper than the tillage depth by making improvements.
(5) In any one of the above aspects, it is characterized in that the interval between the two dense earth dikes adjacent in the advancing direction is set according to the distance that the cultivator advances by tilling at the tilling depth.
(6) In any of the above aspects, the space between one tillage row formed in the forward direction of the cultivator and the adjacent tillage row in the direction perpendicular to the forward direction is set to zero or a predetermined value. It is characterized by setting
(7) In any one of the above aspects, by increasing or decreasing the interval between the two dense earth embankments adjacent in the forward direction and/or the space width between the plowing rows adjacent in the direction perpendicular to the forward direction, Characters and/or pictures consisting of dots and/or lines are expressed on the surface by the solid embankment of the no-tillage portion, or the upper shallow-tillage portion is visually visible from the plowed portion at the predetermined tillage depth. characters and/or pictures made up of dots and/or lines formed by the shallowly cultivated portion of the upper layer are expressed when they are physically distinguishable.
(8) In any one of the above aspects, the construction device including the cultivator includes an elevating cylinder that can extend and contract in a direction perpendicular to the ground surface in order to elevate the cultivator, and the elevating cylinder. a ground tire or ground plate provided at the lower end ,
The ground tire or ground plate is brought into contact with the ground surface in both the contracted state and the extended state of the lifting cylinder .
(9) In any one of the above aspects, using a construction device including the cultivator,
Acquiring positioning information acquired by driving using positioning information technology or terrain data that is existing digital elevation model data ,
Based on the terrain data, the positioning and geographic information analysis system analyzes to obtain analysis results including the terrain, its own position, and the appropriate placement position of the tight embankment ,
In order to construct the solid embankment, it is characterized by automatically adjusting the vertical position of the cultivator and/or the depth of tillage according to the running position.

The dense earth embankment built in the soil layer according to the present invention for suppressing soil erosion of farmland is a technology that utilizes tillage management in agricultural work, and is characterized by being easy for farmers to work on. In particular, since new expensive equipment is not required, countermeasures can be taken at low cost and simply. In addition to various techniques for improving water permeability such as conventional subsoil crushing grooves, the present invention can add the effect of suppressing soil runoff. Furthermore, if the control of tractors such as tractors becomes more advanced due to technological innovations such as ICT construction and precision agriculture, it will be possible to easily form dot- or line-shaped no-tillage areas. As a result, the patchwork pattern in the hilly land is expressed, and regional development is expected through the conservation of soil and the beautiful farmland landscape.

FIGS. 1(a) to 1(d) are side views for explaining a method of constructing a solid earth embankment in a non-plowed portion using a cultivator. FIGS. 2(a) to 2(d) are side views for explaining a method of constructing a tight-dense earth embankment in shallow tillage using a power tiller. FIG. 3 shows an example in which (a) is a non-plowed portion of solid earth embankment and (b) is a lightly tilled portion of solid earth embankment with a predetermined length on a sloping land. Fig. 4 shows an example in which (a) is a solid earth embankment in a non-plowed area and (b) is a solid earthen embankment in a lightly tilled area with a predetermined length on a slope. It shows the effect of suppressing water permeability inside. Fig. 5 shows yet another example in which (a) is a solid earth embankment in a non-plowed portion and (b) is a solid earthen embankment in a shallow tillage portion with a predetermined length on a slope. It shows the effect of suppressing water permeability in the soil layer and the effect of infiltration into deep layers. FIG. 6 is a plan view of an example of a non-plowed solid earth embankment or a lightly tilled solid earth embankment constructed by the cultivator R. As shown in FIG. FIG. 7 shows an example of constructing a compact earth embankment in a no-tillage portion or a compact earthen embankment in a shallow-tillage portion on a curved topographical slope. FIG. 8 shows another example of how to build a compact earth embankment. FIG. 9 shows still another example of the method of constructing a compact earth embankment. FIG. 10 shows an embodiment of a cultivator mounted on a tow vehicle. FIG. 11 shows yet another embodiment of a cultivator mounted on a tow vehicle. FIG. 12 shows an example of a method of constructing a tight earth embankment using a positional information system. FIG. 13 shows a configuration example of a system for constructing a dense earth embankment for no-tillage areas or a solid earth embankment for shallow-plowage areas corresponding to topography and position using a position information system. FIG. 14 shows an example of displaying characters and pictures by dots and lines on the ground surface by constructing a dense earth embankment in a no-tillage portion.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIGS. 1(a) to 1(d) are side views for explaining a method of constructing a solid earth embankment in a non-plowed portion using a cultivator. First, as shown in (a), while the towing vehicle T is being advanced, the tiller R attached to the towing vehicle T is used to plow the firm uncultivated soil 10 to a predetermined plowing depth D to form a tilled layer 11. form. Next, as shown in (b), by raising the cultivator R to a position above the ground surface at a predetermined position in the forward direction, formation of the non-plowed portion 12 is started. , the towing vehicle T is advanced by a predetermined distance. As a result, the untilled portion of the firm uncultivated soil 10 is formed with the width of the cultivator R (the length in the direction perpendicular to the advancing direction). The surface of the untilled portion is covered with plant bodies 14 in a vegetative state or in a dead state. Subsequently, as shown in (C), the cultivator R is again lowered to the predetermined tillage depth D to resume tillage. As a result, as shown in (d), the untilled portion consisting of firm and dense uncultivated soil 10 having a length B corresponding to the advance distance while the cultivator R is raised and the width of the cultivator R. A dense embankment 12 is constructed. The dense earth embankment 12 has a function of suppressing water permeability in the soil layer.

The water permeability in the soil layer here is the water permeability mainly in the direction parallel to the ground surface, and corresponds to the direction of movement of the soil when soil runoff occurs.

FIGS. 2(a) to 2(d) are side views for explaining a method of constructing a tight-dense earth embankment in shallow tillage using a power tiller. First, as shown in (a), while the towing vehicle T is being advanced, the tiller R attached to the towing vehicle T is used to plow the firm uncultivated soil 10 to a predetermined plowing depth D to form a tilled layer 11. form. Next, as shown in (b), at a predetermined position in the forward direction, the cultivator R is raised to a depth below the ground surface and shallower than the tillage depth D to form a shallow tillage portion 11' for shallow tillage. Start. As shown in (c), the towing vehicle T is advanced by a predetermined distance while plowing. As a result, the tight and dense earth embankment 13 of the shallow tillage portion, which is composed of the firm uncultivated soil 10 up to a predetermined depth and the shallow tillage portion 11' above it, extends across the width of the cultivator R (in the direction perpendicular to the forward direction). length). After moving forward by a predetermined distance, as shown in (d), the cultivator R is again lowered to a predetermined tillage depth D, and the tractor T is advanced while tilling. As a result, a compact soil embankment having a length B' corresponding to the advance distance of the cultivator R and a width of the cultivator R, the lower layer being the solid uncultivated soil 10 and the upper layer being the shallow tilled portion 11'. 13 is constructed. The dense earth embankment 13 has a function of suppressing water permeability in the soil layer.

FIG. 3 shows an example in which (a) is a non-plowed portion of solid and dense earth embankment 12 and (b) is a lightly cultivated portion of solid and dense earth embankment 13 with predetermined lengths B and B' on a slope. is shown. Plant bodies 14 in a lush or dead state existing on the ground surface of the dense earth embankment 12 are left as they are. These solid earth embankments 12 and 13 can suppress water permeability in the soil layer.

FIG. 4 shows an example in which (a) is a non-plowed portion of solid and dense earth embankment 12 and (b) is a lightly cultivated portion of solid and dense earth embankment 13 with predetermined lengths B and B' on a slope. , indicating the effect of suppressing permeability in the soil layer. The water W flowing down from the upper side of the sloping land during rainfall is stagnated above the solid and dense earth embankment 12 of the non-plowed part or the solid and dense earth embankment 13 of the shallow tillage part, and the water W in the soil permeates deep. Enhance functionality. As a result, it is possible to promote the infiltration of the surface water W into the ground and suppress the occurrence of soil runoff.

FIG. 5 shows a construction of a firm and dense earth embankment 12 in a non-plowed portion (A) and a firm and dense earth embankment 13 in a shallow tillage portion (B) with predetermined lengths B and B' on sloped land. Another example is shown, showing the effect of suppressing water permeability in the soil layer and the effect of infiltration into deep layers. In the example of FIG. 5, the subsoil crushing ditch 15 is constructed in a deeper layer than the plowing depth D. As shown in FIG. The subsoil crushing ditch 15 is a permeable water-permeable soil 10 crushed by crushing the subsoil or improving the soil layer using a cultivator R before or after the construction of the tight earth embankments 12 and 13. is the high part. The subsoil crushing groove 15 extends toward the ground. The water W flowing down from the upper side of the dense earth embankment during rainfall is stagnated above the solid earth embankment 12 in the no-tillage portion or the solid earth embankment 13 in the shallowly cultivated portion, and is passed through the subsoil crushing ditch 15. It enhances the function of penetrating the water W in the soil into the deep layer. As a result, it is possible to promote the infiltration of the surface water W into the ground and suppress the occurrence of soil runoff.

FIG. 6 is a plan view of an example of a compact earth embankment 12 in a non-plowed portion or a compact earthen embankment 13 in a shallowly cultivated portion constructed by the tiller R. As shown in FIG. Here, a plurality of compact earth dikes 12, 13 are constructed in one plowing row along the forward direction. Furthermore, a plurality of plowing rows are constructed in a direction perpendicular to the advancing direction. By moving the cultivator R up and down while the towing vehicle T is running, the solid embankment 12 of the no-tillage portion of a predetermined length B or the shallow-plowed portion of the predetermined length B' is established at a predetermined position. An earthen embankment 13 can be constructed. For example, in one plowing row, after constructing one solid earth embankment 12, 13, until construction of the next solid earth embankment 12, 13 is started, the tiller R is advanced at a tilling depth D while tilling. The distance is the interval between two solid embankments 12 and 13 adjacent in the forward direction.

In addition, by increasing or decreasing the interval between one plowing row along the forward direction of the towing vehicle T and the adjacent plowing row in the direction perpendicular to the forward direction, a solid earth embankment with a predetermined clearance C is formed. can build. The gap width C can be zero or a predetermined value.

FIG. 7 shows an example of constructing a compact earth embankment 12 for no tillage or a compact earth embankment 13 for shallow tillage on a curved topographical slope. In such terrain, it is desirable to construct solid earth embankments 12, 13 at the midpoint and lower part of the slope. Moreover, it is desirable to adjust the interval between the solid embankments 12 and 13 adjacent to each other in the direction of inclination according to the degree of inclination and length of the slope. Optimally, the steeper the slope, the smaller the length B of the compact soil embankment 12 in the no-tillage portion or the length B' of the compact soil embankment 13 in the shallow-plowed portion, and these compact soil embankments 12, It is preferable to build 13 more closely spaced from a position relatively close to the top of the slope.

FIG. 8 shows another example of the method of constructing the compact earth embankments 12 and 13 . In this example, GPS, GNSS such as GLONASS, a position information system G such as a total station, or known numerical information of terrain is used. Here, a towing vehicle T is equipped with a position information system G. Landform data of the field is obtained from the positional information system G or known numerical information of the landform. Contour lines E indicating the undulations of the field are grasped based on the obtained landform data, and dense earth embankments 12 and 13 are arranged while the towing vehicle T is driven in a direction substantially perpendicular to the contour lines E, for example. In the illustrated example, the compact earth dikes 12 and 13 are constructed so as to be arranged substantially along the contour line E. As shown in FIG.

FIG. 9 shows still another example of the method of constructing the compact earth embankments 12 and 13 . In this example, GPS, GNSS such as GLONASS, a position information system G such as a total station, or known numerical information of terrain is used. Here, a towing vehicle T is equipped with a position information system G. Based on the terrain data thus obtained, the contour lines E indicating the undulations of the field are grasped, and, for example, the compact earth embankments 12 and 13 are arranged while the towing vehicle T is traveling in a direction substantially parallel to the contour lines E. . In this case, the towing vehicle T can be made to draw a curve along the contour line E instead of going straight. The space width C between adjacent tillage rows can also be changed as appropriate.

10 shows an embodiment of a cultivator R mounted on a towing vehicle T. FIG. (a) shows the normal state of the cultivator R. FIG. In this case, a plurality of rotary blades 16 for tilling are arranged and attached evenly in the width direction. (b) shows an example in which a part of the rotary blade in the central part is removed. In this case, the uncultivated soil 10 remains in the portion without the rotary blade, and a dense earth embankment 12 is constructed in the uncultivated portion. (C) shows an example in which a part of the central rotary blade is shortened. In this case, the short portion of the rotary blade constructs a dense embankment 13 in the shallow tillage portion.

The configuration illustrated in FIG. 10 is also applicable to tillage sections having parts other than rotary blades. By changing the plowing portion of the cultivator R in this way, within the range of the width of the cultivator R, a tight earth embankment 12 of the no-tillage portion or a solid earth embankment 13 of the shallow plowing portion is constructed in a part thereof. can. In this example, a compact earth embankment 12, 13 extending in the same direction as the forward movement of the towing vehicle T can be constructed in the center, with tillage layers 11 on both sides thereof. In the illustrated example, one solid earth embankment 12, 13 can be constructed, but by removing or shortening the rotary blades of the cultivator R at a plurality of locations, a plurality of solid earth embankments 12, 13 can be constructed. You can also

FIG. 11 shows yet another embodiment of a cultivator R attached to a tow vehicle T. As shown in FIG. In (a), the cultivator R is provided with an extendable elevating cylinder 17 and a ground tire 18 for elevating contact with the ground surface at the lower end thereof. In (b), a lifting cylinder 17 and a grounding plate 19 contacting the ground surface are provided at the lower end thereof. (C) shows a state in which the tillage layer 11 with a predetermined tillage depth D is formed with the lifting cylinder 17 contracted using the tiller R shown in (A). (d) shows a situation in which the cultivator R shown in (a) is used to construct a dense earth embankment 12 in a non- plowed portion with the lifting cylinder 17 extended. The same applies to the case of using the cultivator R shown in (b).

FIG. 12 shows an example of a method of constructing the solid embankments 12 and 13 using the positional information system G. As shown in FIG. The position information system G is a GPS mounted on the towing vehicle T, a GNSS such as GLONASS, a total station, or known numerical information of terrain. Based on these, the topography of the field is grasped, and the tractor operation system for tillage control provided in the tow vehicle T is automatically used, or manually with reference to the position information system. It is possible to manipulate the start position and end position for constructing a dense earth embankment 13 in the cultivated area. (b) indicates the start position. (b) indicates the construction of the solid earth embankment 12 is in progress.

FIG. 13 shows a configuration example of a system for constructing a dense earth embankment 12 for no-tillage areas or a dense earth embankment 13 for lightly tilled areas corresponding to topography and position using a position information system. When constructing the solid earth embankment 12 in the no-tillage portion or the solid earth embankment 13 in the lightly tilled portion, the cultivator is operated up and down while the towing vehicle is running to obtain a predetermined length B, B' and width. Alternatively, it can be constructed with a predetermined clearance width C by increasing or decreasing the distance between the lines of towing vehicles. As another example, it can be constructed by changing the rotary blade 16 of the cultivator.

Constructing tight and dense embankments 12 and 13 at optimal positions according to the topography, or constructing letters and pictures with dots and lines set in advance on the ground surface with tilled and non-tilled parts, For example, it can be done as follows. Positioning information acquired by tractor driving using positioning information technology or terrain data, which is existing digital elevation model data, is automatically collected or manually input. Terrain data is analyzed by positioning and geographic information analysis system. The analysis results, including the terrain and its own position and the appropriate placement position of the compact embankment, can be sequentially displayed on the display system. After that, according to the traveling position of the tractor, the tractor operating system for tillage control automatically operates the three-point linkage, hitch, and lift cylinder to adjust the height and tillage depth of the tiller, thereby adjusting the compact soil. Embankments 12 and 13 are constructed. As another example, by manually manipulating a three-point hitch, hitch, or lift cylinder through operator manipulation or instruction visually confirming indications on the display system, the cultivator can be raised or lowered or the depth of tillage adjusted. , to build a solid embankment 12, 13. As a result, the tight earth embankments 12 and 13 can be constructed at optimal positions.

FIG. 14 shows an example of displaying characters and pictures by dots and lines on the ground surface by constructing a dense earth embankment 12 in a non-plowed portion. By constructing the dense earth embankment 12 of the no-tillage portion with a predetermined length B and width by adjusting the vertical operation of the cultivator, dots and lines can be freely arranged on the ground surface, and letters and characters can be displayed. It is possible to represent a picture. Even in the case of the dense earth embankment 13 in the shallow- plowed portion, depending on the depth of the shallow-plowed portion, it is possible to visually distinguish it from the tillage layer, and characters and pictures can be displayed.

As described above, in the present invention, a tiller such as a rotary, a harrow, a chisel, a cultivator, or a plow mounted on a towing vehicle is used to plow dense uncultivated soil to a predetermined plowing depth while advancing the farmland. Cultivate extensively. By raising the cultivator above the ground surface or to a shallower depth at a predetermined position on the farmland, a no-tillage or shallow-tillage portion is formed, and in that state, the cultivator is grown to a predetermined length. After that, the cultivator is lowered again to the predetermined tillage depth to resume tillage. As a result, the solid earth embankment of the untilled portion consisting of untilled soil that is wholly firm and dense, or the solid earth embankment of the shallowly cultivated portion that has partially firm untilled soil, can be formed to a predetermined length. and the width of a cultivator.

The constructed solid earth levee stops or retains the surface water that flows down along the slope in the plowed soil layer, thereby attenuating the velocity of the flowing water and promoting underground infiltration, thereby reducing the amount of surface water. Decrease. Soil erosion can be reduced as a result of reduced surface water. Such a dense earth embankment can be implemented very easily and can exhibit a remarkable effect of suppressing soil erosion.

Specifically, a cultivator such as a rotary mounted on a traction vehicle such as a general-purpose agricultural tractor at or before the time when the surface of the farmland becomes bare or nearly bare, when soil erosion is particularly likely to occur. Construct a solid earth embankment using The period is, for example, after harvest, after adding green manure, after sowing to early growth, after harvest to winter, and from thaw to farm work.

If necessary for the construction of a tight earth embankment, we will collect topographical data and utilize geographic information systems and geographic analysis systems. Instead, it is also possible to construct a solid earth embankment without using them by simple operation of driving a towing vehicle and working with a power tiller. It is preferable that the predetermined position of the small part of the farmland where the dense earth embankment is arranged is a position that does not interfere with agricultural work such as seeding work, pesticide spraying, and mechanical weeding.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to realize measures for suppressing soil erosion that can be implemented easily and with a high degree of freedom without interfering with farm work, for farmland conditions that have not been dealt with in the past.

Examples of the present invention and comparative examples are shown below. For convenience of explanation, reference numerals used in the drawings may be used.

[Example]
Table 1 shows the effect of suppressing soil erosion in the case of constructing the dense earth embankment 12 of the present invention using a rotary tiller. In the first treatment area, the subsoil crushing ditch 15 was first arranged in the direction of the contour lines, and then the dense earth embankment 12 was arranged in the non-plowed portion (see FIG. 5). In the second treatment area, only the subsoil crushing ditch 15 was arranged without constructing the dense earth embankment 12 in the no-tillage portion. The effect of suppressing soil runoff was determined by comparing these results.

・Test location: Rubeshibe, Biei -cho, Hokkaido Sloping 8.5 degree field field ・Soil condition: Gray plateau soil ・Field condition: Subsoil crushing in August 2016, oat seeding
In October 2016, the soil was plowed with a rotary tiller for adding green manure. At the middle position of the slope of 190 m, a tight and dense earth embankment 12 with a length B of 1 m and a width of 20 m was constructed in an unplowed portion. In the second treatment area, only the subsoil crushing ditch 15 was arranged without constructing the dense earth embankment 12 in the no-tillage portion.
・Soil runoff measurement period: From October 2016 to May 2017 after snowmelt

The reduction rate of the soil runoff rate was calculated assuming that the reduction rate of the soil runoff amount in the comparative example described later was 0%. In the second treatment area with only the subsoil crushing ditch 15, the reduction rate of soil runoff was 17%, whereas in the first treatment area, there was one solid earth embankment 12 in the no-tillage area. A reduction rate of 52% of soil runoff was obtained just by constructing the system. From this result, it can be seen that the soil erosion control effect of the dense earth embankment 12 in the no-tillage portion is high.

[Comparative example]
Table 2 is a comparative example, showing the results of soil runoff in a test field in a control plot in which the dense earth embankment 12 of the no-tillage portion of the present invention was not constructed and the subsoil crushing ditch 15 was not constructed. .
・Test location: Rubeshibe, Biei-cho, Hokkaido Slope 8.5 degree field ・Soil condition: Gray plateau soil ・Field condition: Oat seeding in August 2016
October 2016 Cultivation with a rotary tiller to incorporate green manure Soil runoff measurement period: October 2016 to May 2017 after snowmelt

B Length of solid earth embankment in no-tillage area B' Length of solid earth embankment in lightly tilled area C Space width D Plowing depth E Contour line G Location information system R Tiller T Towing vehicle W Water 10 Untilled soil 11 tillage layer 11' shallow tillage part 12 no-tillage part dense earth embankment 13 shallow tillage part firm and dense earth embankment 14 plant body 15 subsoil crushing ditch 16 rotary blade 17 lifting cylinder 18 lifting ground tire 19 for lifting ground plate

Claims (9)

A method for constructing a solid earth embankment in a soil layer for suppressing soil erosion in agricultural land, comprising:
In one plowing row, while advancing the tractor vehicle, plowing the compact uncultivated soil to a predetermined plowing depth with a cultivator attached to the tractor vehicle;
At a predetermined position in the forward direction in the one tillage row, the cultivator is raised above the ground surface, and in this state, the traction vehicle is advanced by a predetermined distance in the one tillage row. By lowering the cultivator to the tillage depth and restarting forward tillage in the one tillage row, a solid earth embankment is constructed between two tillage parts in the one tillage row. death,
The firm and dense earth embankment of the untilled portion has a length corresponding to the advance distance while the tiller is raised and a width of the tiller, and is made of firm and dense untilled soil. construction method of a solid earth embankment. A method for constructing a solid earth embankment in a soil layer for suppressing soil erosion in agricultural land, comprising:
Cultivating firm uncultivated soil to a predetermined plowing depth with a cultivator attached to the towing vehicle while advancing the towing vehicle,
At a predetermined position in the forward direction, the cultivator is raised to a depth shallower than the tillage depth, and in this state, the tractor is advanced by a predetermined distance to cultivate, and then the cultivator is lowered to the tillage depth again. By cultivating the land, constructing a tight earth embankment of the upper layer of shallow tillage and the lower layer of uncultivated soil,
A method for constructing a compact earth embankment, wherein the compact earth embankment of the uncultivated soil in the lower layer has a length corresponding to a forward movement distance while the tiller is raised and a width of the tiller. 3. The method of constructing a compact earth embankment according to claim 1, wherein the compact earth embankment of the untilled portion or the compact earth embankment of the untilled soil of the lower layer is constructed on a slope. Before or after the construction of the solid earth embankment of the untilled portion or the solid earth embankment of the uncultivated soil in the lower layer, the subsoil is crushed or the soil layer is improved using a cultivator to reduce the tillage depth. 4. The method for constructing a solid earth embankment according to any one of claims 1 to 3, characterized in that a subsoil crushing ditch with high water permeability is constructed by crushing uncultivated soil that is firm to the deepest layer. 5. The solid earth embankment according to any one of claims 1 to 4, characterized in that the distance between the two adjacent solid earth embankments in the advancing direction is set according to the distance that the cultivator advances by plowing at the tilling depth. How to build a dense earth embankment. A space width between one tillage row formed in the forward direction of the tiller and an adjacent tillage row in a direction perpendicular to the forward direction is set to zero or a predetermined value. 6. The method for constructing a solid earth embankment according to any one of 1 to 5. By increasing or decreasing the spacing between the two tight embankments adjacent in the direction of advance and/or the width of the space between the rows of tillage adjacent in the direction perpendicular to the direction of advance, the firmness of the untilled portion can be increased on the ground surface. Expressing characters and/or pictures consisting of dots and/or lines by a dense embankment, or when the shallow tillage part of the upper layer is visually distinguishable from the tillage part at the predetermined tillage depth 7. The method for constructing a dense earth embankment according to any one of claims 1 to 6, characterized in that letters and/or pictures made up of dots and/or lines are represented by the shallow tillage portion of the upper layer. PreviousA construction device including a cultivator for raising and lowering the cultivatorin a direction perpendicular to the ground surfacean extendable lifting cylinder;provided at the lower end of the lifting cylinderwith a ground tire or ground plateand
The ground tire or ground plate is brought into contact with the ground surface in both the contracted state and the extended state of the lifting cylinder. characterized byA method for constructing a dense earth embankment according to any one of claims 1 to 7. Using a construction device including the cultivator,
Acquiring positioning information acquired by driving using positioning information technology or terrain data that is existing digital elevation model data ,
Based on the terrain data, the positioning and geographic information analysis system analyzes to obtain analysis results including the terrain, its own position, and the appropriate placement position of the tight embankment ,
9. The cultivator according to any one of claims 1 to 8 , wherein the cultivator is automatically adjusted up and down and/or the depth of the cultivator according to the travel position in order to construct the solid earth embankment. How to build a solid earth embankment.

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