Ecological transformation method for inner slope of slope type seawall

Abstract

The invention relates to the technical field of seawall ecological transformation, and discloses a slope type seawall inner slope ecological transformation method which comprises the following steps: selecting a seawall section suitable for ecological transformation according to three first-level indexes, namely a seawall shoreline foundation, hydrology and water quality conditions and surrounding environment conditions; constructing a pool in the selected seawall section according to the terrain; constructing a pool base; and constructing a plant community in the water pool according to the life type, the phenological period and the salt tolerance of the plant. According to the method, a proper transformation section can be selected in combination with various environmental factors of a transformation area, then a corresponding water pool is constructed in combination with the landform, then a proper ecological material is selected to construct a substrate, and different plant communities are constructed in the water pool according to the characteristics of different plants. A natural-imitated seawall ecological space is built, the flood prevention and tide blocking functions of the seawall are guaranteed, the hygrophytes, aquatic plant communities and planktons can be utilized, an inhabiting and foraging environment is built for aquatic animals and hydrophilic birds, and the ecological service function of the seawall is improved.

Description

Technical Field

[0001] This invention relates to the field of ecological transformation technology for seawalls, specifically to an ecological transformation method for the inner slope of a sloping seawall. Background Technology

[0002] The inner slopes of seawalls are mostly constructed with hard materials such as concrete and masonry. While these materials effectively resist tidal impacts and ensure the safety of the seawall, this traditional structure severely impacts the coastal ecosystem. Hard slopes disrupt the natural exchange of matter, energy, and biological information between land and sea, depriving intertidal organisms of their original suitable habitats. Plankton and submerged plants that previously depended on the shallow waters of the inner slopes of seawalls have drastically decreased, leading to a significant loss of shelter and food sources for aquatic animals such as fish, shrimp, and crabs. This results in the degradation of the intertidal ecosystem structure and the loss of biodiversity. Furthermore, hard slopes lead to a scarcity of food resources in the intertidal zone. Unlike the rich aquatic ecosystems of natural seawall inner slopes, which attract numerous waterbirds to rest and forage, the resting and foraging grounds for migratory birds have been significantly reduced, contributing to a decline in both the number and diversity of waterbird populations. In addition, hard slopes cannot effectively absorb and purify water, allowing rainwater runoff to carry large amounts of pollutants directly into the sea, exacerbating eutrophication in nearshore waters and further deteriorating the marine ecosystem.

[0003] As people place increasing emphasis on ecosystem protection, some seawalls have undergone ecological modifications based on their hard slopes. However, due to a lack of comprehensive consideration of various environmental factors on the inner slope of the seawall (such as changes in water level at different elevations and differences in soil salinity), simply planting salt-tolerant plants is insufficient to survive tidal erosion, failing to form stable communities and providing suitable foraging, hiding, or habitat environments for aquatic animals and waterfowl. Consequently, the plant configuration is not closely integrated with the seawall structure, making it difficult to achieve a balance between the seawall's flood control and tide-blocking functions and its ecosystem support functions. Summary of the Invention

[0004] In view of this, the present invention provides an ecological transformation method for the inner slope of a sloping seawall, in order to solve the problem that the various environmental factors of the inner slope of the seawall were not comprehensively considered during the ecological transformation of the seawall, resulting in a loose integration of plant configuration with the seawall structure, making it difficult to achieve a balance between the flood control and tide blocking functions and the ecosystem support function of the seawall.

[0005] In a first aspect, the present invention provides a method for the ecological transformation of the inner slope of a sloping seawall, comprising:

[0006] Based on three primary indicators—the foundation of the seawall shoreline, hydrological and water quality conditions, and surrounding environmental conditions—suitable seawall sections for ecological transformation were selected.

[0007] Construct water tanks according to the terrain in the selected seawall section;

[0008] Construct the base of the pool;

[0009] Plant communities were constructed in the pond based on the plant's life form, phenological period, and salt tolerance.

[0010] Beneficial effects

[0011] This ecological transformation method based on the inner slope of a sloping seawall can combine various environmental factors of the transformation area to select suitable transformation sections, then construct corresponding pools according to the surrounding topography, select appropriate ecological materials to construct the base, and create different plant communities in different locations within the pools based on the characteristics of different plants. This creates a natural-looking seawall ecological space, which not only ensures the seawall's function of flood control and tide blocking, but also utilizes the rich wetland and aquatic plant communities and plankton to create a suitable habitat and foraging environment for aquatic animals and waterfowl, thus enhancing the seawall's ecological service functions.

[0012] In an optional embodiment, the primary indicators of the seawall shoreline are divided into three secondary indicators: geological conditions, soil conditions, and slope structure; the primary indicators of hydrological and water quality conditions are divided into three secondary indicators: inundation duration, wind and wave intensity, and water quality; and the primary indicators of the surrounding environmental conditions are divided into two secondary indicators: the surrounding ecological foundation and the intensity of human activities.

[0013] Beneficial effects

[0014] The three primary indicators of seawall shoreline foundation, hydrological and water quality conditions and surrounding environmental conditions are further refined into eight secondary indicators, which can build a systematic evaluation system to fully cover key factors and ultimately select the seawall section most suitable for ecological transformation.

[0015] In an optional embodiment, the weights of each primary and secondary indicator are determined using the analytic hierarchy process (AHP).

[0016] Beneficial effects

[0017] The Analytic Hierarchy Process (AHP) can be used to rationally allocate the weights of various indicators and select areas suitable for improvement.

[0018] In an optional embodiment, the slope ratio of the pool is 1:5 to 1:3.

[0019] In one optional embodiment, the water depth ranges from [0, 0.3] m in the shallow area of ​​the pool, from [0.3, 1.0] m in the transition area, and from [1.0, 1.5] m at the bottom of the pool.

[0020] In an optional embodiment, the surface layer of the substrate is made of ecological slope protection material, and the bottom layer of the substrate is made of impermeable material.

[0021] In one optional embodiment, the base surface material at the pool inlet is a grass-planting brick made of salt-resistant concrete, the base surface material at the pool waist is a plant fiber ecological blanket, and the base surface material at the pool bottom is a gabion mesh with a mixed matrix of gravel and soil.

[0022] In an optional embodiment, the underlying material of the substrate is clay or a geomembrane.

[0023] In one alternative embodiment, salt-tolerant wetland plants are planted in the poolside area, salt-tolerant emergent plants are planted in the shallow water area, and salt-tolerant submerged plants are planted in the transition area.

[0024] Beneficial effects

[0025] By planting different plants in different areas of the pond according to their growth characteristics, a stable plant community can be formed, which is conducive to creating a diverse ecological environment and providing a suitable habitat and foraging environment for aquatic animals and water birds.

[0026] In an optional embodiment, the salt-tolerant wetland plant is *Iris tectorum*, the salt-tolerant emergent plant is *Phragmites australis*, and the salt-tolerant submerged plant is *Potamogeton crispus*. Attached Figure Description

[0027] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0028] Figure 1 This is a flowchart of an ecological transformation method for the inner slope of a sloping seawall according to the present invention.

[0029] Figure 2 This is a schematic diagram of the ecological transformation of the inner slope of a sloping seawall.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1. Seawall section;

[0032] 2. Pool;

[0033] 3. Geomembrane;

[0034] 4. Salt-loving iris;

[0035] 5. Reeds;

[0036] 6. Potamogeton crispus;

[0037] 7. Stone blocks and nut blocks;

[0038] 8. Revetment. Detailed Implementation

[0039] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0042] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0043] The following is combined Figures 1 to 2 The following describes embodiments of the present invention.

[0044] According to an embodiment of the present invention, in one aspect, an ecological transformation method for the inner slope of a sloping seawall is provided, comprising:

[0045] S1: Based on three primary indicators—the foundation of the seawall shoreline, hydrological and water quality conditions, and surrounding environmental conditions—the seawall section 1 suitable for ecological transformation was selected.

[0046] S101: The foundation of the seawall shoreline refers to the geological, topographical, and structural stability conditions of the area where the seawall is located, which is the physical foundation for ecological transformation.

[0047] Furthermore, the primary indicators of the seawall shoreline are divided into three secondary indicators: geological conditions, soil conditions, and slope structure.

[0048] Geological conditions mainly refer to the geological structure, soil and rock types, and stability characteristics of the area where the seawall is located. Geological structure specifically includes soil and rock types, geological structure, and groundwater conditions. Soil and rock types, such as bedrock (e.g., granite, limestone), sandy soil, and cohesive soil (e.g., silt, clay), should be selected based on their strong erosion resistance and sufficient bearing capacity. For geological structures, it's crucial to determine whether the area is located on fault lines, folds, or seismically active zones, choosing a stable region to avoid damage from geological movements. Groundwater conditions need to be assessed based on water level, permeability, and salinity to determine if drainage is necessary and if the area is suitable for vegetation growth. A comprehensive assessment suggests selecting an area with stable geological conditions.

[0049] Soil conditions refer to the physicochemical properties of the soil in and around the seawall, directly affecting vegetation growth and ecosystem stability. Soil type, salinity, nutrients, and pH value need to be considered. A comprehensive assessment should select areas with suitable soil particle size and salinity, conducive to plant growth.

[0050] Slope structure refers to the geometry and surface protection methods of the inner slope of a seawall, which determines the space for ecological transformation and its erosion resistance. A comprehensive assessment should prioritize areas where the existing slope structure is relatively easy to modify.

[0051] S102: Hydrological and water quality conditions refer to the hydrodynamic conditions and water quality characteristics of the sea area where the seawall is located, which directly affect the material cycle and biological survival of the ecosystem.

[0052] Furthermore, the primary indicators of hydrological and water quality conditions are divided into three secondary indicators: inundation duration, wind and wave intensity, and water quality conditions.

[0053] Submersion duration refers to the periodic length of time during which the intertidal zone of a seawall is submerged and exposed by seawater due to tidal action. It is a key factor determining the type and function of the intertidal ecosystem. Areas with moderate submersion duration (4-8 hours per day) and small tidal range (less than 2 meters) are preferable to promote the coordinated development of diverse biological communities.

[0054] Wave intensity refers to the wave energy generated by wind in the sea area where the seawall is located, which directly affects the stability of the seawall structure and the survival rate of ecological elements. It is advisable to choose an area with low wave intensity (wave height less than 1 meter) and dispersed wind direction.

[0055] Water quality refers to the physical and chemical properties of the water in the sea area where the seawall is located, which directly affects the material cycle and biological health of the ecosystem. Areas with good water quality, balanced nutrients, and moderate transparency should be selected.

[0056] S103: Surrounding environmental conditions refer to the intensity of human activities and the ecological background around the seawall, reflecting the social acceptance and ecological potential of ecological transformation.

[0057] Furthermore, the primary indicator of surrounding environmental conditions is divided into two secondary indicators: the surrounding ecological foundation and the intensity of human activities.

[0058] The surrounding ecological foundation refers to the original state and biodiversity level of the natural ecosystem surrounding the seawall, serving as a biological resource pool and ecological functional base for ecological transformation. Areas with high native vegetation cover, diverse animal communities, and a sound ecological foundation should be selected.

[0059] Human activity intensity refers to the frequency and intensity of human development, utilization, and disturbance activities around seawalls, directly affecting the stability and restoration potential of the ecosystem. Areas with low human activity intensity and no point source pollution should be selected.

[0060] Furthermore, the weights of each primary and secondary indicator are determined using the Analytic Hierarchy Process (AHP). Specifically, in this embodiment, the weights of each primary and secondary indicator are shown in Table 1 (AHP Site Selection Index System Table).

[0061]

[0062] Table 1. Site Selection Index System of Analytic Hierarchy Process (AHP)

[0063] S2: Construct a pool 2 in the selected seawall section 1 according to the terrain;

[0064] The inner slope of the seawall is itself a slope, and pools 2 of varying depths are constructed at different locations based on the undulating terrain of the slope. Specifically, pool 2 is approximately 15–20m long and 3–5m wide, with its long axis parallel to the centerline of the seawall. The slope of pool 2 is designed as a gentle slope, with a slope ratio of 1:5–1:3.

[0065] In other embodiments, the slope of pool 2 may be designed as stepped.

[0066] Furthermore, the water depth requirements vary in different areas of pool 2. The water depth range in the shallow area of ​​pool 2 is [0, 0.3] m, the water depth range in the transition area is [0.3, 1.0] m, and the water depth range at the bottom of the pool is [1.0, 1.5] m.

[0067] S3: Construct the base of the pool;

[0068] Furthermore, the surface layer of the base is made of ecological slope protection material, and the bottom layer of the base is made of impermeable material.

[0069] Suitable surface and bottom materials need to be selected to construct the pool base. The surface material should be an ecological slope protection material with high permeability, good durability, and conducive to biological attachment and growth. The bottom material should be an impermeable material to retain water and prevent leakage.

[0070] Specifically, the base surface material at the pool opening is made of salt-resistant concrete grass pavers, which can resist salt erosion and extend the structural life by virtue of the high corrosion resistance of salt-resistant concrete, and can also achieve rapid drainage and reduce salt deposition.

[0071] The base surface material located at the waist of the pool is made of plant fiber ecological blankets or vegetation bags. Leveraging the natural degradability and water and fertilizer retention properties of plant fibers, a stable microenvironment is provided for plant growth, enabling rapid greening and ecological restoration. Its flexible structure can adapt to the complex curved surface of the waist area and micro-deformation of the foundation, reducing the risk of cracking. Simultaneously, the interwoven root system and fibers form a reinforcing layer, effectively preventing soil erosion and inhibiting salt upwelling, thus combining ecological function with structural stability.

[0072] The base surface material at the bottom of the pool is a gabion mesh made of a mixture of gravel and soil. This design utilizes the high strength and flexibility of the gabion mesh to adapt to foundation deformation and prevent structural cracking. The permeability of the gravel accelerates drainage and reduces water pressure, while the soil in the mixed substrate provides growing conditions for vegetation, promoting ecological soil stabilization and water purification. Its porous structure also provides habitat for aquatic organisms, balancing structural stability, ecological function, and biodiversity.

[0073] The base material is either clay or geomembrane 3. Clay, with its natural low permeability, can effectively block water seepage, and it is readily available and inexpensive. Geomembrane 3, on the other hand, boasts the advantages of high strength, high impermeability, and chemical corrosion resistance of synthetic materials, enabling it to adapt to complex foundation deformations and provide long-term stable seepage prevention.

[0074] S4: Based on the life form, phenological period and salt tolerance of the plants, a plant community was constructed in pond 2.

[0075] By scientifically configuring multi-level plant communities based on the life forms, phenological periods, and salt tolerance of plants, and by ensuring that plants grow, reproduce, and wither throughout the year to maintain the continuity of ecological functions, a stable and functionally diverse water pond plant ecosystem is ultimately constructed.

[0076] Furthermore, salt-tolerant wetland plants are planted along the edge of the pond, salt-tolerant emergent plants in the shallow water area, and salt-tolerant submerged plants in the transition area. Specifically, the salt-tolerant wetland plants are *Iris halophila* or *Iris pseudacorus*, the salt-tolerant emergent plants are *Phragmites australis* or *Bolboschoenus maritimus*, and the salt-tolerant submerged plants are *Potamogeton pectinatus* or *Ruppia maritima*.

[0077] The following specific construction examples illustrate the methods of ecological transformation:

[0078] First, three candidate seawall sections, A, B, and C, were selected. The Analytic Hierarchy Process (AHP) was used to evaluate various indicators. Finally, based on the comprehensive evaluation results, seawall section C was selected for ecological transformation. The scores of various indicators for the three candidate seawall sections A, B, and C are shown in Table 2 below (Scoring Table for Site Selection Factors of Each Section).

[0079] Then, in section C of the seawall, two pools 2 were constructed on the inner slope by excavation and filling. Each pool is approximately 15m long and 3m wide, with its long axis parallel to the centerline of the seawall. The slope of pool 2 is designed as a gentle slope with a ratio of 1:5. The water depth in the shallow area is controlled at 0–0.3m, the water depth in the transition area at 0.3–1.0m, and the water depth at the bottom of the pools at 1.0–1.2m.

[0080]

[0081] Table 2 Scoring Table for Site Selection Factors in Each Section

[0082] On the seaward revetment 8 of pool 2, grass pavers made of salt-resistant concrete are used to stabilize the slope structure and support plant growth. Vegetation bags are laid on the surface of the pool waist to support plant growth. Geomembrane 3 is applied to the bottom layer of the pool for seepage prevention. At the same time, boulders and nuts 7 are placed to help benthic animals inhabit the area.

[0083] Furthermore, salt-tolerant wetland plants such as yellow iris (Iris pseudacorus) and salt-loving iris (Iris halophila) are planted in the pond-side area, salt-tolerant emergent plants such as reed (Phragmites australis) are planted in the shallow water area, and salt-tolerant submerged plants such as pondweed (Potamogeton pectinatus) are planted in the transition area to form a multi-layered plant community, providing a continuous habitat and foraging environment for aquatic animals and waterfowl.

[0084] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for ecological transformation of the inner slope of a sloping seawall, characterized in that, include: Based on three primary indicators—the foundation of the seawall shoreline, hydrological and water quality conditions, and surrounding environmental conditions—suitable seawall sections for ecological transformation were selected (1). In the selected seawall section (1), a pool (2) is constructed according to the terrain; Construct the base of the pool; Plant communities were constructed in the pond (2) based on the plant life form, phenological period and salt tolerance.

2. The method for ecological transformation of the inner slope of a sloping seawall according to claim 1, characterized in that, The primary indicators of the seawall shoreline are divided into three secondary indicators: geological conditions, soil conditions, and slope structure; the primary indicators of hydrological and water quality conditions are divided into three secondary indicators: inundation duration, wind and wave intensity, and water quality; and the primary indicators of the surrounding environmental conditions are divided into two secondary indicators: the surrounding ecological foundation and the intensity of human activities.

3. The method for ecological transformation of the inner slope of a sloping seawall according to claim 2, characterized in that, The weights of each primary and secondary indicator are determined using the Analytic Hierarchy Process (AHP).

4. The method for ecological transformation of the inner slope of a sloping seawall according to claim 1, characterized in that, The slope ratio of the pool (2) is 1:5-1:

3.

5. The method for ecological transformation of the inner slope of a sloping seawall according to claim 1, characterized in that, The water depth range of the shallow area of ​​the pool (2) is [0, 0.3] m, the water depth range of the transition area is [0.3, 1.0] m, and the water depth range of the bottom of the pool is [1.0, 1.5] m.

6. The method for ecological transformation of the inner slope of a sloping seawall according to claim 1, characterized in that, The surface layer of the base is made of ecological slope protection material, and the bottom layer of the base is made of impermeable material.

7. The method for ecological transformation of the inner slope of a sloping seawall according to claim 6, characterized in that, The base surface material at the pool opening is made of grass bricks made of salt-resistant concrete, the base surface material at the middle of the pool is made of plant fiber ecological blankets, and the base surface material at the bottom of the pool is made of gabion mesh with a mixed substrate of gravel and soil.

8. The method for ecological transformation of the inner slope of a sloping seawall according to claim 6, characterized in that, The base material is clay or geomembrane (3).

9. The method for ecological transformation of the inner slope of a sloping seawall according to claim 1, characterized in that, Salt-tolerant wetland plants are planted along the edge of the pool, salt-tolerant emergent plants are planted in the shallow water area, and salt-tolerant submerged plants are planted in the transition area.

10. The method for ecological transformation of the inner slope of a sloping seawall according to claim 9, characterized in that, The salt-tolerant wetland plant is iris salsa (4), the salt-tolerant emergent plant is reed (5), and the salt-tolerant submerged plant is Potamogeton crispus (6).

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