Bamboo check dam construction method for preventing and controlling benggang erosion sediment diffusion

Abstract

Disclosed in the present invention is a method for constructing a bamboo check dam in a Benggang gully. The method comprises: building branch check dams at the mouth of a Benggang gully and in the Benggang gully, wherein the branch check dams are sited at narrow sections where the gully has a relatively gentle gradient and a large area available for sediment deposition; and then planting bamboo plants in a region between the bottom of Benggang and the branch check dam at the mouth of the Benggang gully, and planting herbaceous plants between the bamboos. After bamboo-planting management is performed, the content of nutrients, such as organic matters, nitrogen and phosphorus, in soil of a Benggang gully bed and an alluvial (proluvial) fan is significantly increased, the soil is thus improved, and the plant growth conditions are also improved. Sustainable management and utilization can be achieved after bamboo forests are established, and selective felling for use in construction, transportation, furniture, papermaking, weaving crafts, etc. can bring certain economic benefits.

Description

A method for constructing a bamboo valley pavilion to prevent erosion and sediment diffusion of landslides Technical field:

[0001] The invention belongs to the field of soil and water conservation management, and specifically relates to a method for constructing a bamboo valley for preventing and controlling gully erosion and silt diffusion. Background technology:

[0002] Collapse gullies are the most serious type of soil erosion in southern China, widespread across the southern hilly and low mountainous regions. Severe gully erosion can easily cause regional ecological degradation, damage to critical downstream infrastructure, and significant economic losses, severely threatening regional food security, ecological safety, and human safety. It presents a major challenge in natural disaster prevention and control in southern my country. Traditional gully management typically employs a "blocking above, blocking below, cutting in the middle, and greening inside and outside" approach. Ditches are drilled on the catchment slopes above the gullies to intercept surface runoff. Gullies or dams are constructed at the mouths or downstream of the gullies to intercept runoff and sediment. Planting platforms are constructed on exposed slopes within the gullies, such as collapsed walls and colluvial deposits. However, this approach involves extensive engineering measures and is costly, often requiring the use of large machinery. Its implementation is often limited by various conditions. To reduce management costs, some areas currently simply construct earthen gullies or earthen dams at the mouths or downstream of the gullies to retain sediment, preventing or mitigating the direct impact of gully erosion on downstream areas. However, due to the convergence of the water-collecting slopes above the collapsing gullies and the steepness of the internal slopes, headwater erosion at the gully head, collapse of the wall, and secondary erosion of the collapsing body continue to occur, resulting in large amounts of sediment accumulating in front of the gullies or sand dams. Some of the sediment is even discharged downstream with runoff from the spillway. After long-term continuous erosion and siltation, the gully mouth area at the bottom of the collapsing gully has become a sediment accumulation area, and the conditions for vegetation growth have become extremely poor, mostly becoming barren land. Even if trees and shrubs are planted, it is difficult for them to grow into forests. The safety and stability of the gullies or sand dams are also affected to a certain extent, with cracks or damage occurring and they are easily filled with silt. The high-sediment runoff discharged from the spillway also directly threatens the ecological security of the areas downstream of the collapsing gullies.

[0003] Summary of the invention:

[0004] The present invention aims to provide a method for constructing bamboo gorges within collapsing gullies. This method utilizes artificial intervention to improve plant growth conditions in the channel area from the bottom of the collapsing gully to the gully entrance. By leveraging the rapid growth, strong root consolidation, and resistance to submergence of bamboo plants, the method prevents the spread of sediment from collapsing gullies downstream, thereby addressing the shortcomings of previously mentioned gorges or sand dams in managing collapsing gully erosion and sediment production.

[0005] The method for constructing a bamboo valley of the present invention is characterized by: firstly building a branch valley at the narrow part of the collapsing gully and the gully, then planting bamboo plants in the area from the bottom of the collapsing gully to the collapsing gully, and planting grass plants between the bamboos.

[0006] Preferably, the specific steps are as follows:

[0007] a. Construction of branch valleys: Build water-permeable, sand-impermeable branch valleys at the mouth of the collapsing gully and in the gully. Choose a location where the gully gradient is gentle and the gully width is narrow. Drive bamboo stakes into the valleys and fill the spaces between them with branches to create branch valleys.

[0008] b. Land preparation and hole digging: Bamboo plants are planted in rows perpendicular to the direction of water flow, using a "pin"-shaped hole digging method. In the area of ​​​​collapse planting, the land is leveled and the planting holes are dug according to this specification. After digging the holes, apply sufficient base fertilizer to each hole;

[0009] c. Planting bamboo plants: Planting should be done in March and April every year. Choose two-year-old clumping bamboo with a stem thickness of 5 to 20 cm (preferably local bamboo). Dig out the bamboo with the stump, cut off the bamboo top, leaving a stem of 1.5 to 2.0 m and 2 to 3 coiled branches, and keep the rhizome of the bamboo species intact. When planting, cut it obliquely from the internode, cut the end of the bamboo stem into an oblique end, put the bamboo seeds into the hole, cover it with soil, and use degradable ecological bags to fill the collapsing sand on the spot and pile it on the bamboo roots to help the bamboo survive.

[0010] d. Planting herbs: Sow grass seeds such as Bermuda grass, broad-leaved paspalum, and molasses grass in the open space between the bamboo pockets (mix the grass seeds with organic fertilizer and soil thoroughly before sowing). After the grass seeds germinate, they can quickly increase the surface vegetation coverage and create a good habitat for the survival of bamboo.

[0011] Further preferably, the specific steps are as follows:

[0012] a. Construction of branch valleys: Build water-permeable, sand-impermeable branch valleys at the mouth of the collapsing gully and in the gully. Choose a location where the gully gradient is gentle and the gully width is narrow. First, clear the rocks there and drive 1.5m high bamboo stakes into the ground to a depth of 0.5m. The spacing between each bamboo stake is 20-30cm. Use local materials and fill the space between the bamboo stakes with branches to build a branch valley. Depending on the specific topography of the collapsing gully, multiple branch valleys can be built in the narrow part of the gully.

[0013] b. Land preparation and hole digging: Bamboo plants are densely planted in a "pin-shaped" pattern with rows perpendicular to the direction of water flow, with a spacing of 1m between rows. In the area of ​​collapsed hills, the land is leveled and the planting holes are dug according to this specification. The planting holes are 0.8m long, 0.6m wide, and 0.4m deep. After digging the holes, apply sufficient base fertilizer to each hole. The base fertilizer can be compound fertilizer or organic fertilizer. The application rate of compound fertilizer is 0.25kg / hole, and the application rate of organic fertilizer is 40-50kg / hole. If the soil has a high sand content, add cultivated soil to improve the soil quality.

[0014] c. Planting bamboo plants: Planting should be done in March and April every year. Choose two-year-old clumping bamboo with a stem thickness of 5 to 20 cm (local bamboo is preferred). Dig out the bamboo with the stump, cut off the bamboo top, leave 1.5 to 2.0 m of stem and 2 to 3 coiled branches, and keep the rhizome of the bamboo species intact, protect the buds and root points. When planting, cut obliquely from the internodes, chop the end of the bamboo stem into an oblique mouth, put the bamboo seeds into the hole (plant 2 to 4 trees in each hole), cover them with soil, use degradable ecological bags made locally to fill 20 to 30 kg of collapsing sand, and place 1 bag horizontally at the upper and lower positions of the bamboo roots to prevent bamboo root erosion, which is conducive to bamboo survival.

[0015] d. Planting Herbs: Thoroughly mix molasses grass, bermudagrass, and broadleaf paspalum seeds, organic fertilizer, and collapsing sandy soil in a mass ratio of 1:10:100. Sow the grass seeds in the spaces between the bamboo holes. After planting the grass seeds and bamboo, water thoroughly through the top 20 cm of soil. Because the grass seeds germinate quickly and increase surface vegetation cover, they can suppress high temperatures on the surface of the collapsing gullies, creating a favorable habitat for bamboo.

[0016] The present invention primarily uses plant-based measures to control the erosion and sediment spread of collapsing gullies, saving management costs and achieving significant benefits in collapsing gullies. Bamboo plants have natural reproductive capacity, strong shoot and tillering ability, rapid growth rate, upright branches, and lush foliage. Planted in the same year, they produce shoots and tillers in the same year, mature into a forest in the second year, and effectively block collapsing gullies by the third year, playing the role of retaining sand and consolidating soil. Bamboo plants have well-developed root systems that spread outward in a network-like pattern and can gather downward in deeper soil layers, forming clusters of bamboo stumps with their well-developed whip roots. The crisscrossing root systems and intertwined bamboo stumps can effectively slow down and disperse runoff and retain sediment. After implementing bamboo planting management, the organic matter and nitrogen and phosphorus content of the soil in the collapsing gully beds and alluvial (flood) fans is significantly increased, the soil is improved, and plant growth conditions are enhanced. After bamboo forests have matured, they can be sustainably managed and utilized, and selective felling can be used for construction, transportation, furniture, papermaking, weaving, etc., to achieve certain economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic plan view of the system for preventing and controlling the spread of erosion and sediment from collapsing hills;

[0018] Figure 2 is a schematic cross-sectional diagram of the system for preventing and controlling the spread of landslide erosion and sediment. Specific implementation method:

[0019] The following examples are provided to further illustrate the present invention, but are not intended to limit the present invention.

[0020] Example 1:

[0021] As shown in FIG1 and FIG2, the method for strengthening the landslide ridge sand retention and soil consolidation of the present invention is described below in conjunction with FIG1 and FIG2, and the specific steps are as follows:

[0022] In areas with relatively straight, narrow, and large mobile collapsing gullies, the land should be leveled from the gully mouth to the bottom of the collapsing gully. Bamboo planting holes should be dug in rows perpendicular to the water flow. The holes should be spaced 1 meter apart both vertically and horizontally, with a size of 0.8m x 0.6m x 0.4m. After digging, apply 0.25kg of compound fertilizer to each hole. Bamboo should be planted in March and April. Species include Dendrocalamus latifolia, Dendrocalamus truncatus, or Dendrocalamus truncatus. Choose two-year-old bamboo strips with a stem thickness of 5-20cm. Dig out the bamboo with the stump and trim off the top, leaving a stem of 1.5-2.0m and two to three twisted branches. Keep the rhizome intact, especially protecting the buds and root points. When planting, cut the bamboo plants obliquely through the internodes, and cut the stem ends into an oblique cut to catch rainfall and retain moisture. During planting, bamboo seeds are placed in rows perpendicular to the direction of water flow, covered with soil, and 2 to 4 bamboo plants are planted per hole. Grass seeds such as molasses grass, bermudagrass, and broadleaf paspalum are sown in the spaces between the bamboo plants. Investigations and monitoring have shown that bamboo shoot production in March exceeds 50% within the same year of planting. After six months of growth, a single bamboo plant can produce 3 to 5 tillers. The root system is well-developed, forming a network-like structure that converges 30 to 40 cm deep, consolidating the soil. The large root mass forms individual bamboo stumps, which disperse and slow runoff, protecting the soil from erosion. Monitoring results (see Table 1) show that under the same rainfall conditions, the bamboo planting area has a 36.5% reduction in annual runoff, a 15.1% reduction in runoff coefficient, and a 66.5% reduction in sand yield modulus compared to the control area (no bamboo planting and no branch grate), demonstrating significant water and soil conservation benefits. Bamboo planting increases soil fertility, significantly improving plant growth conditions. According to sampling and analysis (see Table 2), soil organic matter, total nitrogen, total phosphorus, and total potassium levels in the bamboo-planted areas increased by 38.9%, 41.3%, 28.6%, and 13.6%, respectively, compared to the control areas. Bamboo planting also increases local farmers' income. Bamboo, with its fast growth, short lifespan, wide range of uses, and high economic value, is widely used in construction, transportation, furniture, papermaking, and weaving.

[0023] Table 1 Soil and water conservation benefits in the bamboo planting area of ​​collapsed hills

[0024] Table 2 Soil nutrient content in the bamboo planting area of ​​the collapsed hill

Claims

1. A method for constructing a bamboo valley for preventing and controlling the spread of erosion and silt from collapsing ridges, comprising the following steps: First, a branch valley that is permeable to water but not sand is constructed at the mouth of the Benggang gully and in the ditch. The location is chosen where the ditch gradient is gentle and the width is narrow. Then, bamboo plants are planted in the area between the bottom of the Benggang and the branch valley at the mouth of the ditch, and herbaceous plants are planted between the bamboos to form a bamboo valley.

2. The method according to claim 1, wherein the specific steps are as follows: a. Constructing branch valleys: construct water-permeable and sand-impermeable branch valleys at the mouth of the collapsing gully and in the ditch. The location is selected where the ditch gradient is gentle and the ditch width is narrow. Bamboo stakes are driven in and branches are filled between the bamboo stakes to build branch valleys. b. Land preparation and hole digging: Bamboo plants are planted in rows perpendicular to the direction of water flow in a "pin-shaped" hole digging method. In the collapsing planting area, the land is leveled and the planting holes are dug according to this specification. After digging the holes, sufficient basal fertilizer is applied to each hole; c. Planting bamboo plants: Plant in March and April every year. Choose two-year-old clumping bamboo with a stem thickness of 5 to 20 cm (preferably local bamboo). Dig out the bamboo with the stump, cut off the bamboo top, leave a stem of 1.5 to 2.0 m and 2 to 3 coiled branches, and keep the rhizome of the bamboo species intact. When planting, cut it obliquely from the internodes, cut the end of the bamboo stem into an oblique mouth, put the bamboo seeds into the hole, cover it with soil, use degradable ecological bags made from local materials to fill the collapsed sand and pile it on the bamboo roots, which is conducive to the survival of the bamboo. d. Planting herbs: Sow grass seeds such as Bermuda grass, broad-leaved paspalum, and molasses grass in the open space between the bamboo pockets (mix the grass seeds with organic fertilizer and soil thoroughly before sowing). After the grass seeds germinate, they can quickly increase the surface vegetation coverage and create a good habitat for the survival of bamboo.

3. The method according to claim 2, wherein the specific steps are as follows: a. Construction of branch valleys: Build water-permeable and sand-impermeable branch valleys at the mouth of the collapsing gully and in the ditch. Choose a location where the ditch gradient is gentle and the ditch width is narrow. First, clear the stones there and drive in 1.5m high bamboo stakes. The bamboo stakes are 0.5m deep in the soil, and the distance between each bamboo stake is 20-30cm. Use local materials and fill branches between the bamboo stakes to build a branch valley. According to the specific collapsing gully, the branch valley is built. The topography of the ditch allows the construction of multiple branch valleys in narrow places; b. Land preparation and hole digging: Bamboo plants are densely planted in a "pin-shaped" hole digging method in a direction perpendicular to the direction of water flow, with a row spacing of 1m. In the collapsing planting area, the land is leveled and the planting holes are dug according to this specification. The planting hole specifications are 0.8m long, 0.6m wide, and 0.4m deep. After digging the hole, apply enough basal fertilizer to each hole. The basal fertilizer can be compound fertilizer or organic fertilizer. The application rate of compound fertilizer is 0.25kg / hole, and the application rate of organic fertilizer is 40-50kg / hole. If the soil has a high sand content, add cultivated soil to improve the soil quality; c. Planting bamboo plants: Plant in March and April every year. Choose two-year-old clumping bamboo with a stem thickness of 5 to 20 cm (preferably local bamboo). Dig out the bamboo with the stump, cut off the bamboo top, leave a stem of 1.5 to 2.0 m and 2 to 3 coiled branches, and keep the rhizome of the bamboo species intact, protect the buds and root points. When planting, cut obliquely from the internodes, chop the end of the bamboo stem into an oblique mouth, put the bamboo seeds in the hole (plant 2 to 4 trees in each hole), cover them with soil, use degradable ecological bags to fill 20 to 30 kg of collapsing sand and soil, and place 1 bag horizontally at the upper and lower positions of the bamboo roots to prevent bamboo root erosion, which is conducive to bamboo survival. d. Planting herbs: Mix molasses grass, bermudagrass, broadleaf paspalum seeds, organic fertilizer, and collapsing sand soil thoroughly. The mass ratio of grass seeds to organic fertilizer and collapsing sand soil is 1:10:100, and spread them in the open space between bamboo holes. Water the grass seeds and bamboo once after planting, and water the top 20cm of soil thoroughly. Since grass seeds can germinate quickly and increase the surface vegetation coverage, they can inhibit the high temperature on the surface of the collapsing gully, creating a strong habitat for the survival of bamboo.

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