Method for constructing medium slope riparian buffer zone in cold region based on non-point source pollution blocking

Abstract

The invention discloses a method for constructing a medium slope riparian buffer zone in a cold region based on non-point source pollution blocking, and belongs to the technical field of river non-point source pollution treatment in the cold region. Submerged plants are planted in the submerged plant unit on the lower portion of the system by 15 cm in the river bank direction, pumice of 15 cm is placed close to the edge of the vegetation, and the whole unit is alternately and sequentially arranged; the upper emergent aquatic plant unit and the submerged plant corresponding unit are vacant, the unit corresponding to the pumice stone is used for placing emergent aquatic plant planting baskets and planting emergent aquatic plants, and a biological ribbon is suspended between the two units in the system; a living willow pile is wedged into a middle slope bottom riverbed at the position where the slope top extends towards the water surface by 0.7-1 m, gravel-cobble is laid at the bottom of the riverbed to the living willow pile, the long edge of a sand retention and turbidity reduction system is vertically placed on the gravel-cobble in the river bank direction, and the space between the river bank and the willow pile and the gap between the river bank and the willow pile are filled with the gravel-cobble; shrubs and arbors are planted close to the sand retention and turbidity reduction system to serve as an arbor and shrub interception area; herbaceous plants are planted close to the arbor and shrub interception area to serve as a herbaceous retention area.

Description

Technical Field

[0001] The invention relates to the field of river ecological protection / environmental governance, and in particular to a method for constructing a mid-slope riverbank buffer zone in cold regions based on non-point source pollution blocking. Background Art

[0002] Non-point source pollution has surpassed point source pollution to become the main source of ecological and environmental pollution, and is one of the important environmental issues affecting the quality of my country's water environment. Riverbank buffers intercept a large amount of nutrients, organic matter, pesticides and other pollutants from surface runoff, farmland runoff, and deep underground runoff through filtration, infiltration, absorption and sedimentation, and are an effective means of non-point source pollution control. Affected by topographic conditions, longitude and latitude, altitude, social factors and other factors, the interception and conversion efficiency of pollutants in riverbank buffers of different vegetation types varies significantly. At the same time, the width and slope of riverbank buffers are also important factors affecting pollutant reduction. However, the current riverbank buffer construction technology focuses more on the construction of buffer plant communities, and less consideration is given to the width of buffers and the interception characteristics of buffers with different slopes, which seriously affects the pollutant interception effect of riverbank buffers. Summary of the invention

[0003] The purpose of the present invention is to solve the problems existing in the above-mentioned technologies and further provide a method for constructing a mid-slope riverbank buffer zone in cold regions based on non-point source pollution blocking.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] A method for constructing a buffer zone on steep slope riverbanks in cold regions based on non-point source pollution blocking.

[0006] Step 1: Riverbank buffer zone finishing: In April every year, select a medium-slope riverbank buffer zone with a slope of 12%-50%, remove stones and weeds from the substrate, level the slope, and trim it until the slope substrate is firm;

[0007] Step 2: Make the framework of the sediment retention and turbidity reduction system. Use wire mesh to form a support beam as the system framework. The framework is 3-5m long, 0.6-0.9m wide, and 0.4-0.6m high. Two units of emergent plants and submerged plants are set perpendicular to the river bank. Each unit is divided by wire mesh with an interval of 0.3m.

[0008] Step 3: Production of sediment retention and turbidity reduction system units. The system is divided into an upper emergent plant unit and a lower submerged plant unit. 15 cm submerged plants are planted along the lower edge of the system perpendicular to the long direction of the system. The submerged plants are selected from one or a combination of Myriophyllum, Ceratophyllum and Potamogeton. 15 cm pumice is placed next to the submerged plants. The submerged plants and pumice units are arranged alternately in sequence and separated from the upper emergent plant unit by wire mesh. The vacant unit of the emergent plants corresponds to the submerged plants up and down. The emergent plant planting basket corresponds to the pumice part of the submerged plant unit up and down. The emergent plants are selected from one or a combination of calamus, cattail, Zizania and water onion. Biological streamers are hung between the submerged plants and the emergent plant units. The two ends of the streamers are hung on both sides of the system respectively. The length of the streamers is 0.9 to 1.2 m.

[0009] Step 4: Place a sand retention and turbidity reduction system. At a point extending 0.7 to 1 m from the top of the slope to the water surface, wedge a living tree stump of a willow tree with a length of 1.2 to 1.5 m and a middle diameter of 4 to 6 cm into the riverbed at the bottom of the middle slope. The wedging depth is 0.8 to 1.1 m, the height of the above-ground part is 0.2 to 0.3 m, and the density is 0.45 to 0.65 m. Spread pebbles and gravels at the bottom of the riverbed to the living willow stumps. Place the long side of the sand retention and turbidity reduction system vertically on the pebbles and gravels along the river bank, and fill the gap between the river bank and the willow stumps with pebbles and gravels.

[0010] Step 5. In the tree and shrub interception area, shrubs with a width of not less than 3m are planted near the sand retention and turbidity reduction system. The planting varieties are one or a combination of Spiraea serrata, Pearl Bush and Red Rhododendron, 3-4 year old seedlings, and the plant spacing × row spacing is 1.5m × 1.5m. Next to the shrubs, 4-5 year old tree seedlings are planted. The tree varieties are one or a combination of poplar, Salix matsudana and Salix artemisiae, and the plant spacing × row spacing is 3m × 3m. The planting hole specifications are: 50cm × 50cm × 50cm;

[0011] Step 6: Herbaceous retention area: Plant a herbaceous retention area with a width of not less than 5m adjacent to the tree and shrub interception area. The planting varieties are one or any combination of bluegrass, red fescue and white clover. The seeds are 25g / m 2 Sow in spring.

[0012] In step 3, the particle size of the pumice is 10 to 20 mm.

[0013] In step 4, the particle size of the pebbles and gravels is 5 to 8 cm.

[0014] In step 4, the density is the spacing between rows and plants.

[0015] The outstanding feature of the present invention is that the sand retention and turbidity reduction system, willow piles, pebbles and gravel are combined with plants to repair and construct the mid-slope river bank buffer zone in cold areas, which significantly improves the purification capacity of the mid-slope buffer zone for non-point source pollution. In 2015, an experiment was conducted in the riverbank zone of Ash River in Chenggaozi Town, Xiangfang District, Harbin (N45°40′9.83″, E126°54′4.16″~N45°40′30.13″, E126°53′45.04″). The experimental length was 1 km. The continuous monitoring results in 2017 and 2018 showed that compared with the middle slope (control) where the riverbank buffer zone was not constructed, the amount of sediment decreased by 14.3-17.9%, the total nitrogen removal rate increased by 10.3-11.7%, and the total phosphorus removal rate increased by 12.4-13.1%. In addition, the invention is simple to operate and has wide applicability. It is affordable for governments, enterprises and institutions, and can significantly improve the regional ecological environment. It is of great significance to maintain regional ecological security and protect riverbank buffer zones. At the same time, it can provide a solid ecological guarantee for regional economic and social development. The invention can be used for the restoration and construction of middle slope buffer zones in cold regions. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of modeling for the construction method of steep slope riverbank buffer zones in cold regions based on non-point source pollution blocking.

[0017] Figure 2 Schematic diagram of the sediment retention and turbidity reduction system. DETAILED DESCRIPTION

[0018] The present invention will be further described in detail below: This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method is given, but the protection scope of the present invention is not limited to the following embodiments.

[0019] Example 1

[0020] like Figure 1 Figure 2 As shown in the figure, the method for constructing a buffer zone of steep slope riverbank in cold regions based on non-point source pollution blocking is as follows:

[0021] Step 1: Riverbank buffer zone finishing: In April every year, select a medium-slope riverbank buffer zone with a slope of 12%-50%, remove stones, weeds and other debris from the matrix, and properly level the slope surface until the slope matrix is ​​firm;

[0022] Step 2: Make the skeleton of the sediment retention and turbidity reduction system. Use wire mesh to form a support beam (frame) as the system skeleton. The skeleton is 3m long, 0.6m wide and 0.5m high. Two units of emergent plants and submerged plants are set vertically in the river bank direction. Each unit is divided by wire mesh with an interval of 0.3m.

[0023] Step 3: Production of sediment retention and turbidity reduction system units. The system is divided into an upper emergent plant unit and a lower submerged plant unit. A 15 cm submerged plant Myriophyllum is planted along the lower edge of the system perpendicular to the long direction of the system. A 15 cm pumice (particle size 10-20 mm) is placed next to the submerged plant. The submerged plant and pumice units are arranged alternately in sequence and separated from the upper emergent plant unit by a wire mesh. The vacant unit of the emergent plant corresponds to the submerged plant up and down. The water plantain planted in the emergent plant planting basket corresponds to the pumice part of the submerged plant unit up and down. A biological streamer is hung between the submerged plant and the emergent plant unit. The two ends of the streamer are hung on both sides of the system respectively. The streamer is 0.9 m long.

[0024] Step 4: Place a sand retention and turbidity reduction system. At 0.7m from the top of the slope to the water surface, wedge a 1.2m long and 4-6cm middle diameter willow stump into the riverbed at the bottom of the middle slope. The wedging depth is 0.8m, the height of the above-ground part is 0.2-0.3m, and the density (spacing between rows and plants) is 0.5m. Spread pebbles (particle size 5-8cm) at the bottom of the riverbed to the living willow stumps. Place the long side of the sand retention and turbidity reduction system vertically on the pebbles along the river bank, and fill the gap between the river bank and the willow stumps and the river bank with pebbles.

[0025] Step 5. In the tree and shrub interception area, plant 4m wide Spiraea shrubs near the sand retention and turbidity reduction system. The 3-year-old seedlings have a plant spacing × row spacing of 1.5m × 1.5m. Plant 4-5-year-old poplar seedlings next to the shrubs with a plant spacing × row spacing of 3m × 3m. The planting hole specifications are: (length, width and height) 50cm × 50cm × 50cm;

[0026] Step 6: Herbaceous retention area: Plant a 5m wide herbaceous retention area next to the tree and shrub interception area. The varieties are one or any combination of bluegrass, red fescue and white clover. The seeds are 25g / m 2 Sow in spring.

[0027] Example 2

[0028] like Figure 1 Figure 2 As shown in the figure, the method for constructing a buffer zone of steep slope riverbank in cold regions based on non-point source pollution blocking is as follows:

[0029] Step 1: Riverbank buffer zone finishing: In April every year, select a medium-slope riverbank buffer zone with a slope of 12%-50%, remove stones, weeds and other debris from the matrix, and properly level the slope surface until the slope matrix is ​​firm;

[0030] Step 2: Make the skeleton of the sediment retention and turbidity reduction system. Use wire mesh to form a support beam (frame) as the system skeleton. The skeleton is 4m long, 0.9m wide and 0.45m high. Two units of emergent plants and submerged plants are set vertically in the river bank direction. Each unit is divided by wire mesh with an interval of 0.3m.

[0031] Step 3: Make the sediment retention and turbidity reduction system unit. The system is divided into an upper emergent plant unit and a lower submerged plant unit. A 15 cm submerged plant, Dermatophyte, is planted along the lower edge of the system perpendicular to the long direction of the system. A 15 cm pumice (particle size 10-20 mm) is placed next to the submerged plant. The submerged plant and pumice units are arranged alternately in sequence and separated from the upper emergent plant unit by a wire mesh. The vacant unit of the emergent plant corresponds to the submerged plant up and down. The Zizania latifolia planted in the emergent plant planting basket corresponds to the pumice part of the submerged plant unit up and down. A biological streamer is hung between the submerged plant and the emergent plant unit. The two ends of the streamer are hung on both sides of the system respectively. The streamer is 1 m long.

[0032] Step 4: Place a sand retention and turbidity reduction system. At 0.7m from the top of the slope to the water surface, wedge a 1.3m long and 4-6cm middle diameter willow stump into the riverbed at the bottom of the middle slope. The wedging depth is 0.9m, the height of the above-ground part is 0.2-0.3m, and the density (spacing between rows and plants) is 0.55m. Spread pebbles (particle size 5-8cm) at the bottom of the riverbed to the living willow stumps. Place the long side of the sand retention and turbidity reduction system vertically on the pebbles along the river bank, and fill the gap between the river bank and the willow stumps and the river bank with pebbles.

[0033] Step 5. In the tree and shrub interception area, plant shrubs such as pearl bush or red yew with a width of 3m near the sand retention and turbidity reduction system. The 3-4-year-old seedlings have a plant spacing × row spacing of 1.5m × 1.5m. Plant trees such as Salix matsudana with a plant spacing × row spacing of 3m × 3m next to the shrubs. The planting hole specifications are: (length, width and height) 50cm × 50cm × 50cm;

[0034] Step 6: Herbaceous retention area: Plant a 5m wide herbaceous retention area next to the tree and shrub interception area. The varieties are red fescue and white clover, or any combination of the two. The seeds are 25g / m 2 Sow in spring.

[0035] Example 3

[0036] like Figure 1 Figure 2 As shown in the figure, the method for constructing a buffer zone of steep slope riverbank in cold regions based on non-point source pollution blocking is as follows:

[0037] Step 1: Riverbank buffer zone finishing: In April every year, select a medium-slope riverbank buffer zone with a slope of 12%-50%, remove stones, weeds and other debris from the matrix, and properly level the slope surface until the slope matrix is ​​firm;

[0038] Step 2: Make the skeleton of the sediment retention and turbidity reduction system. Use wire mesh to form a support beam (frame) as the system skeleton. The skeleton is 5m long, 0.8m wide and 0.4m high. Two units of emergent plants and submerged plants are set perpendicular to the river bank. Each unit is divided by wire mesh with an interval of 0.3m.

[0039] Step 3: Production of sediment retention and turbidity reduction system units. The system is divided into an upper emergent plant unit and a lower submerged plant unit. A 15 cm submerged plant Potamogeton is planted along the lower edge of the system perpendicular to the long direction of the system. A 15 cm pumice (particle size 10-20 mm) is placed next to the submerged plant. The submerged plant and pumice units are arranged alternately in sequence and separated from the upper emergent plant unit by a wire mesh. The vacant unit of the emergent plant corresponds to the submerged plant up and down. The calamus planted in the emergent plant planting basket corresponds to the pumice part of the submerged plant unit up and down. A biological streamer is hung between the submerged plant and the emergent plant unit. The two ends of the streamer are hung on both sides of the system respectively. The streamer is 1.2 m long.

[0040] Step 4: Place a sand retention and turbidity reduction system. At the top of the slope extending 1m to the water surface, wedge a living tree stump of a willow tree with a length of 1.4m and a middle diameter of 4-6cm into the riverbed at the bottom of the middle slope. The wedging depth is 1.1m, the height of the above-ground part is 0.2-0.3m, and the density (spacing between rows and plants) is 0.65m. Spread pebbles (particle size 5-8cm) on the bottom of the riverbed to the living willow stumps. Place the long side of the sand retention and turbidity reduction system vertically on the pebbles along the river bank, and fill the gap between the river bank and the willow stumps and the river bank with pebbles;

[0041] Step 5: In the tree and shrub interception area, plant the shrub Redwood with a width of 3.4m near the sand retention and turbidity reduction system. The 3-4 year old seedlings have a plant spacing × row spacing of 1.5m × 1.5m. Plant the tree Artemisia selengensis next to the shrubs. The 4-5 year old seedlings have a plant spacing × row spacing of 3m × 3m. The planting hole specifications are: (length, width and height) 50cm × 50cm × 50cm;

[0042] Step 6: Herbaceous retention area: Plant a 5m wide herbaceous retention area next to the tree and shrub interception area. The variety is white clover, and the seeds are 25g / m 2 Sow in spring.

[0043] Example 4

[0044] like Figure 1 Figure 2 As shown in the figure, the method for constructing a buffer zone of steep slope riverbank in cold regions based on non-point source pollution blocking is as follows:

[0045] Step 1: Riverbank buffer zone finishing: In April every year, select a medium-slope riverbank buffer zone with a slope of 12%-50%, remove stones, weeds and other debris from the matrix, and properly level the slope surface until the slope matrix is ​​firm;

[0046] Step 2: Make the skeleton of the sediment retention and turbidity reduction system. Use wire mesh to form a support beam (frame) as the system skeleton. The skeleton is 4.5m long, 0.7m wide and 0.6m high. Two units of emergent plants and submerged plants are set perpendicular to the river bank. Each unit is divided by wire mesh with an interval of 0.3m.

[0047] Step 3: Production of sediment retention and turbidity reduction system units. The system is divided into an upper emergent plant unit and a lower submerged plant unit. A 15 cm submerged plant, Dermatophyllum japonicum, is planted along the lower edge of the system perpendicular to the long direction of the system. A 15 cm pumice (particle size 10-20 mm) is placed next to the submerged plant. The submerged plant and pumice units are arranged alternately in sequence and separated from the upper emergent plant unit by a wire mesh. The vacant unit of the emergent plant corresponds to the submerged plant up and down. The cattail planted in the emergent plant planting basket corresponds to the pumice part of the submerged plant unit up and down. A biological streamer is hung between the submerged plant and the emergent plant unit. The two ends of the streamer are hung on both sides of the system respectively. The streamer is 1.1 m long.

[0048] Step 4: Place a sand retention and turbidity reduction system. At the top of the slope extending 1m to the water surface, wedge a living tree stump of a willow tree with a length of 1.5m and a middle diameter of 4-6cm into the riverbed at the bottom of the middle slope. The wedging depth is 1.0m, the height of the above-ground part is 0.2-0.3m, and the density (spacing between rows and plants) is 0.45m. Spread pebbles (particle size 5-8cm) on the bottom of the riverbed to the living willow stumps. Place the long side of the sand retention and turbidity reduction system vertically on the pebbles along the river bank, and fill the gap between the river bank and the willow stumps and the river bank with pebbles;

[0049] Step 5: In the tree and shrub interception area, plant the shrub Redwood with a width of 3m near the sand retention and turbidity reduction system. The 3-4-year-old seedlings have a plant spacing × row spacing of 1.5m × 1.5m. Plant the tree Salix matsudana with a plant spacing × row spacing of 3m × 3m next to the shrubs. The planting hole specifications are: (length, width and height) 50cm × 50cm × 50cm;

[0050] Step 6: Plant the herb retention area with a width of 5m of red fescue adjacent to the tree and shrub interception area. The seeds are 25g / m 2 Sow in spring.

[0051] The above are only preferred specific embodiments of the present invention, which are all different implementations based on the overall concept of the present invention, and the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for constructing a buffer zone on a steep river bank in cold regions based on non-point source pollution blocking, characterized in that: Step 1: Riverbank buffer zone finishing: In April every year, select a medium-slope riverbank buffer zone with a slope of 12%-50%, remove stones and weeds from the substrate, level the slope, and trim it until the slope substrate is firm; Step 2: Make the framework of the sediment retention and turbidity reduction system. Use wire mesh to form a support beam as the system framework. The framework is 3-5m long, 0.6-0.9m wide, and 0.4-0.6m high. Two units of emergent plants and submerged plants are set vertically in the river bank direction. Each unit is divided by wire mesh with an interval of 0.3m. Step 3: Production of sediment retention and turbidity reduction system units. The system is divided into an upper emergent plant unit and a lower submerged plant unit. 15 cm submerged plants are planted along the lower edge of the system perpendicular to the long direction of the system. The submerged plants are selected from one or a combination of Myriophyllum, Ceratophyllum and Potamogeton. 15 cm pumice is placed next to the submerged plants. The submerged plants and pumice units are arranged alternately in sequence and separated from the upper emergent plant unit by wire mesh. The vacant unit of the emergent plants corresponds to the submerged plants up and down. The emergent plant planting basket corresponds to the pumice part of the submerged plant unit up and down. The emergent plants are selected from one or a combination of calamus, cattail, Zizania and water onion. Biological streamers are hung between the submerged plants and the emergent plant units. The two ends of the streamers are hung on both sides of the system respectively. The length of the streamers is 0.9 to 1.2 m. Step 4: Place a sand retention and turbidity reduction system. At a point extending 0.7 to 1 m from the top of the slope to the water surface, wedge a living tree stump of a willow tree with a length of 1.2 to 1.5 m and a middle diameter of 4 to 6 cm into the riverbed at the bottom of the middle slope. The wedging depth is 0.8 to 1.1 m, the height of the above-ground part is 0.2 to 0.3 m, and the density is 0.45 to 0.65 m. Spread pebbles and gravels at the bottom of the riverbed to the living willow stumps. Place the long side of the sand retention and turbidity reduction system vertically on the pebbles and gravels along the river bank, and fill the gap between the river bank and the willow stumps with pebbles and gravels. Step 5. In the tree and shrub interception area, shrubs with a width of not less than 3m are planted near the sand retention and turbidity reduction system. The planting varieties are one or a combination of Spiraea serrata, Pearl Bush and Red Rhododendron, 3-4 year old seedlings, and the plant spacing × row spacing is 1.5m × 1.5m. Next to the shrubs, 4-5 year old tree seedlings are planted. The tree varieties are one or a combination of poplar, Salix matsudana and Salix artemisiae, and the plant spacing × row spacing is 3m × 3m. The planting hole specifications are: 50cm × 50cm × 50cm; Step 6: Herbaceous retention area: Plant a herbaceous retention area with a width of not less than 5m adjacent to the tree and shrub interception area. The planting varieties are one or any combination of bluegrass, red fescue and white clover. The seeds are 25g / m 2 Sow in spring.

2. The method for constructing a buffer zone on a steep slope river bank in cold regions based on non-point source pollution blocking according to claim 1, characterized in that: In step 3, the particle size of the pumice is 10 to 20 mm.

3. The method for constructing a buffer zone on a steep slope river bank in cold regions based on non-point source pollution blocking according to claim 1, characterized in that: In step 4, the particle size of the pebbles and gravels is 5 to 8 cm.

4. The method for constructing a buffer zone on a steep slope river bank in cold regions based on non-point source pollution blocking according to claim 1, characterized in that: In step 4, the density is the spacing between rows and plants.

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