Method for ecological restoration and reconstruction of river estuary

Abstract

The present disclosure provides a river estuary ecological restoration reconstruction method, and relates to the technical field of ecological restoration. The ecological restoration reconstruction method comprises the following steps: determining an ecological restoration area at a river estuary; determining an average low tide water level and an average high tide water level of the ecological restoration area; removing surface floating silt and soft soil layer in the ecological restoration area, and compactly reinforcing the underlying riverbed foundation; determining a high-risk erosion area in the ecological restoration area below the average low tide water level; performing structural reinforcement treatment on the high-risk erosion area; setting a hidden dam below the average low tide water level in the ecological restoration area; setting a dam at a position corresponding to the average high tide water level of the ecological restoration area; setting a reinforced and anti-filtration composite material layer on the foundation between the hidden dam and the dam in the ecological restoration area; and setting the reinforced and anti-filtration composite material layer on the foundation in the high-risk erosion area and at least part of the area after the structural reinforcement treatment.

Description

Technical Field

[0001] This disclosure relates to the field of ecological restoration technology, and more specifically, to a method for ecological restoration and reconstruction of river estuaries. Background Technology

[0002] In coastal ecological restoration projects, especially in the remediation of river estuaries, the current mainstream methods are mostly hardening-oriented, such as the extensive use of vertical revetments, concrete-filled riprap, or large-scale dumping of artificial irregular blocks. However, such technical solutions leave an excessive artificial trace and lose the heterogeneity of the landscape.

[0003] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this disclosure is to provide a method for ecological restoration and reconstruction of river estuaries.

[0005] According to one aspect of this disclosure, a method for ecological restoration and reconstruction of river estuaries is provided, comprising: Determine ecological restoration areas at river estuaries; Determine the average low tide level and average high tide level of the ecological restoration area; Remove the surface silt and soft soil layer in the ecological restoration area, and carry out compaction and reinforcement treatment on the underlying riverbed foundation; High-risk erosion areas were identified within the ecological restoration area located below the average low tide level; Structural reinforcement treatment was carried out on the high-risk erosion areas; A hidden dam is constructed below the average low tide level in the ecological restoration area. A dike shall be constructed at the location corresponding to the average high tide level in the ecological restoration area. A reinforced and filter composite material layer is installed on the foundation between the hidden dam and the embankment in the ecological restoration area; The reinforced and filter composite material layer is provided on the foundation of the high-risk erosion area and on at least a portion of the area that has undergone the structural reinforcement treatment.

[0006] In one exemplary embodiment of this disclosure, the underlying riverbed foundation is subjected to compaction and reinforcement treatment, including: Vibratory compaction or dynamic compaction treatment is carried out on the underlying riverbed foundation.

[0007] In one exemplary embodiment of this disclosure, structural reinforcement treatment is performed on the high-risk erosion area, including: In the high-risk erosion area, at least one of the following is used for structural reinforcement: riprap, gabion baskets, and reinforced concrete piles.

[0008] In one exemplary embodiment of this disclosure, the riprap is placed in the high-risk erosion area and fixed in the foundation by the reinforced concrete piles inserted into the ground.

[0009] In one exemplary embodiment of this disclosure, the reinforced and filter composite material layer is disposed on at least a portion of the riprap, and the end of the reinforced and filter composite material layer away from the dam is fixed by the reinforced concrete pile.

[0010] In one exemplary embodiment of this disclosure, the reinforced and filter composite material layer includes at least one of a three-dimensional geonet and a high-strength woven geotextile.

[0011] In one exemplary embodiment of this disclosure, the ecological restoration and reconstruction method further includes: A filter layer, a stabilizing layer, and a wave-resistant energy dissipation layer are sequentially disposed on the reinforced and filter composite material layer.

[0012] In one exemplary embodiment of this disclosure, the filter layer comprises crushed stone with a particle size of 5cm to 15cm, the stabilizing layer comprises boulders with a particle size of 15cm to 30cm, and the wave-resistant and energy-dissipating layer comprises large boulders or artificial irregularly shaped blocks with a particle size of 30cm to 50cm.

[0013] In one exemplary embodiment of this disclosure, the ecological restoration and reconstruction method further includes: The tidal flat area above the ecological restoration area was identified; The hidden dam is constructed on the side of the tidal flat area away from the riverbank.

[0014] In one exemplary embodiment of this disclosure, the ecological restoration and reconstruction method further includes: Identify areas of severe water turbulence within the ecological restoration zone; An energy dissipation structure is installed in the area of ​​intense water flow turbulence.

[0015] The ecological restoration and reconstruction method for river estuaries disclosed herein addresses the complex hydrodynamic conditions in river estuaries, where the intensity of tidal cycles, runoff confluence, and wave disturbances varies significantly with spatial location. By clearly defining the ecological restoration area, this method ensures that engineering measures are precisely applied to the key areas requiring restoration, thereby reducing unnecessary ecological disturbances and resource waste.

[0016] The average low tide level and average high tide level are core indicators for hydrodynamic zoning in estuary areas. They determine the flow patterns, wave impact intensity, sediment deposition rate, and ecological succession potential at different locations. Based on these two levels, the subsequent deployment of hidden dams (below the low tide level), the construction of dikes (corresponding to the high tide level), and the construction of the protective layer (between the two) all have clear basis, achieving the adaptation of engineering measures to tidal rhythm and avoiding the impact of water level fluctuations on the stability of the engineering structure.

[0017] The estuary area is subject to long-term runoff and tidal forces, resulting in a surface layer of silt. This silt layer has extremely low bearing capacity and is easily eroded away by water flow. Directly laying a facing structure on it can easily lead to uneven foundation settlement, structural cracking, or even overall instability. Removing the surface silt allows direct contact with the underlying stable soil layer, providing a reliable bearing layer for all subsequent engineering structures and avoiding the risk of damage due to foundation deformation. Simultaneously, the compaction and reinforcement treatment significantly reduces the soil porosity and increases soil density by compacting and consolidating the foundation soil. This greatly enhances the foundation's resistance to liquefaction and its bearing capacity, ensuring stability under long-term hydrodynamic loads and providing long-term reliable foundation support for the entire restoration project. The removal of surface silt and the compaction of the foundation provide a flat and stable base for the subsequent laying of reinforced filter layers and graded stone filter layers, thus completing the creation of a biodiversity-friendly base. This not only avoids the clogging of the filter layer by weak soil, but also provides a more stable substrate environment for benthic organisms, balancing engineering stability and ecological needs.

[0018] High-risk erosion areas in the estuary region mainly include scour pits, weak foundation zones, the toes of dikes, and the bases of groynes. These areas are critical weak points characterized by intense water turbulence and scouring, and are also the most vulnerable parts of existing engineering structures. Preliminary surveys identified these high-risk erosion areas, enabling precise allocation of protective resources and avoiding the cost waste and ecological damage associated with indiscriminate protection. Structural reinforcement of these high-risk erosion areas effectively resisted strong hydrodynamic scouring, eliminating the risk of engineering damage and providing crucial stability for the entire restoration system. Furthermore, by reinforcing only localized high-risk erosion areas rather than implementing comprehensive shoreline hardening, the natural mudflats and intertidal environment of low-energy zones were preserved to the greatest extent possible. This avoided the disruption of ecological connectivity caused by large-scale hardening, achieving synergy between engineering protection and ecological conservation, and significantly reducing the intensity of disturbance to the estuarine ecosystem.

[0019] Hidden dikes, positioned below low tide, reflect, break up, and dissipate incident waves, significantly reducing wave energy and the direct impact on the downstream shoreline. This reduces the driving force for shoreline erosion, creating conditions for siltation and stabilization of the downstream beach. Compared to traditional offshore dikes, hidden dikes remain underwater at low tide, with no exposed hard structures, minimizing visual impact and achieving invisible protection, avoiding the landscape damage associated with traditional revetments. The deployment of hidden dikes guides the direction of runoff and tidal currents, adjusts the flow field distribution in the estuary area, reduces concentrated scouring of local shorelines by the main current, and promotes the deposition of suspended sediment in the area behind the dike. This gradually shapes natural landforms such as silt-forming mudflats and tidal channels, achieving a geomorphic restoration model guided by engineering and shaped by nature, rather than artificially altering the landscape, significantly reducing the long-term maintenance requirements of the project.

[0020] The dike is located at the high tide level, forming a double protection system with the hidden dike below the low tide level. The hidden dike is responsible for reducing most of the energy of the incident waves, while the dike resists the impact of the remaining high tide water flow. This forms a progressive protection structure that first dissipates energy and then provides protection, which greatly improves the overall protection capacity of the shoreline, reduces the stress load on the dike, and extends the service life of the project.

[0021] The reinforced and filter composite material layer strengthens the foundation soil through the tensile strength of the geosynthetic material, improving the overall anti-sliding stability of the soil and preventing the slope soil from sliding failure under hydrodynamic action. On the other hand, its filter function allows water to drain freely while preventing foundation soil particles from being carried away by the water flow, preventing seepage failure such as soil erosion and ensuring the long-term stability of the foundation.

[0022] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0024] Figure 1 This is a schematic diagram of a river estuary provided for one embodiment of this disclosure.

[0025] Figure 2 This is a schematic diagram of ecological restoration and reconstruction of a river estuary provided as an embodiment of the present disclosure.

[0026] Figure 3A cross-sectional schematic diagram of ecological restoration and reconstruction of a river estuary provided for one embodiment of this disclosure.

[0027] Figure 4 A flowchart of an ecological restoration and reconstruction method for a river estuary provided in one embodiment of this disclosure. Detailed Implementation

[0028] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed description will be omitted.

[0029] Although relative terms such as "up" and "down" are used in this specification to describe the relative relationship of one component of an icon to another, these terms are used only for convenience, such as according to the orientation of the examples shown in the accompanying drawings. It is understood that if the device of the icon is flipped upside down, the component described as "up" will become the component described as "down." When a structure is "up" of another structure, it may mean that the structure is integrally formed on the other structure, or that the structure is "directly" mounted on the other structure, or that the structure is "indirectly" mounted on the other structure through another structure.

[0030] The terms “a,” “one,” “the,” “the,” and “at least one” are used to indicate the presence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” and “third,” etc., are used only as markers and are not a limitation on the number of objects.

[0031] This disclosure provides a method for ecological restoration and reconstruction of river estuaries, such as... Figures 1-4 As shown, it includes: Step S100: Determine the ecological restoration area at the river estuary; Step S200: Determine the average low tide level and average high tide level of the ecological restoration area; Step S300: Remove the surface silt and soft soil layer in the ecological restoration area, and carry out compaction and reinforcement treatment on the underlying riverbed foundation; Step S400: Identify high-risk erosion areas within the ecological restoration area located below the mean low tide level; Step S500: Reinforce the structure of high-risk erosion areas; Step S610: Set up a hidden dam below the average low tide level in the ecological restoration area; Step S620: Construct a dike at the location corresponding to the average high tide level in the ecological restoration area; Step S710: Install a reinforced and filter composite material layer on the foundation between the hidden dam and the dike in the ecological restoration area; Step S720: Install a reinforced and filter composite material layer on the foundation of the high-risk erosion area and on at least part of the area that has undergone structural reinforcement treatment.

[0032] The ecological restoration and reconstruction method for river estuaries disclosed herein addresses the complex hydrodynamic conditions in these areas, where the intensity of tidal cycles, runoff confluence, and wave disturbances varies significantly with spatial location. This method involves clearly defining the ecological restoration area (e.g., Figure 2 The ecological surface layer construction area within the ecological surface layer construction line shown in the diagram) ensures that engineering measures are precisely applied to the key areas that need restoration, reducing unnecessary ecological disturbance and resource waste.

[0033] The average low tide level and average high tide level are core indicators for hydrodynamic zoning in estuary areas. They determine the flow patterns, wave impact intensity, sediment deposition rate, and ecological succession potential at different locations. Based on these two water levels, the subsequent layout of the hidden dam 11 (below the low tide level), the setting of the dike 12 (at the corresponding location of the high tide level), and the construction of the protective layer (between the two) all have clear basis, achieving the adaptation of engineering measures to tidal rhythm and avoiding the impact of water level fluctuations on the stability of the engineering structure.

[0034] The estuary area is subject to long-term runoff and tidal forces, resulting in a surface layer of silt. This silt layer has extremely low bearing capacity and is easily eroded away by water flow. Directly laying a facing structure on it can easily lead to uneven foundation settlement, structural cracking, or even overall instability. Removing the surface silt allows direct contact with the underlying stable soil layer, providing a reliable bearing layer for all subsequent engineering structures and avoiding the risk of damage due to foundation deformation. Simultaneously, the compaction and reinforcement treatment significantly reduces the soil porosity and increases soil density by compacting and consolidating the foundation soil. This greatly enhances the foundation's resistance to liquefaction and its bearing capacity, ensuring stability under long-term hydrodynamic loads and providing long-term reliable foundation support for the entire restoration project. The removal of surface silt and the compaction of the foundation provide a flat and stable base for the subsequent laying of reinforced filter layers and graded stone filter layers, thus completing the creation of a biodiversity-friendly base. This not only avoids the clogging of the filter layer by weak soil, but also provides a more stable substrate environment for benthic organisms, balancing engineering stability and ecological needs.

[0035] High-risk erosion areas in the estuary region mainly include scour pits, weak foundation zones, the toes of dikes, and the bases of groynes. These areas are critical weak points characterized by intense water turbulence and scouring, and are also the most vulnerable parts of existing engineering structures. Preliminary surveys identified these high-risk erosion areas, enabling precise allocation of protective resources and avoiding the cost waste and ecological damage associated with indiscriminate protection. Structural reinforcement of these high-risk erosion areas effectively resisted strong hydrodynamic scouring, eliminating the risk of engineering damage and providing crucial stability for the entire restoration system. Furthermore, by reinforcing only localized high-risk erosion areas rather than implementing comprehensive shoreline hardening, the natural mudflats and intertidal environment of low-energy zones were preserved to the greatest extent possible. This avoided the disruption of ecological connectivity caused by large-scale hardening, achieving synergy between engineering protection and ecological conservation, and significantly reducing the intensity of disturbance to the estuarine ecosystem.

[0036] The Hidden Dam 11, positioned below low tide, reflects, breaks up, and dissipates incident waves, significantly reducing wave energy and the direct impact on the downstream shoreline. This reduces the driving force for shoreline erosion, creating conditions for siltation and stabilization of the downstream beach. Compared to traditional offshore breakwaters, Hidden Dam 11 remains underwater at low tide, with no exposed hard structure, minimizing visual impact and achieving invisible protection, thus avoiding the landscape damage associated with traditional revetments. The deployment of Hidden Dam 11 guides the direction of runoff and tidal currents, adjusts the flow field distribution in the estuary area, reduces concentrated scouring of local shorelines by the main current, and promotes sediment deposition in the downstream area, gradually shaping natural landforms such as silt-forming mudflats and tidal channels. This achieves a landform restoration model guided by engineering and shaped by nature, rather than artificially altering the landform, significantly reducing the long-term maintenance requirements of the project.

[0037] The dike 12 is located at the high tide level, forming a double protection system with the hidden dike 11 below the low tide level. The hidden dike 11 is responsible for reducing most of the energy of the incident waves, while the dike 12 resists the impact of the remaining high tide water flow. This forms a progressive protection structure that first dissipates energy and then provides protection, which greatly improves the overall protection capability of the shoreline, reduces the stress load on the dike 12, and extends the service life of the project.

[0038] The reinforced and filter composite material layer 30 reinforces the foundation soil through the tensile strength of the geosynthetic material, thereby improving the overall anti-sliding stability of the soil and preventing the slope soil from sliding failure under hydrodynamic action. On the other hand, its filter function allows water to drain freely while preventing foundation soil particles from being carried away by the water flow, preventing seepage failure such as soil erosion, and ensuring the long-term stability of the foundation.

[0039] In some embodiments, breakwaters can be designed as multi-tiered or perforated structures to create diverse flow zones and habitats. Ecological reef systems (such as oyster reefs and artificial seagrass reefs) can also be used to replace parts of traditional rocky breakwaters, directly constructing productive habitats.

[0040] In some embodiments, the underlying riverbed foundation 20 is subjected to compaction and reinforcement treatment, including: vibratory compaction or dynamic compaction treatment of the underlying riverbed foundation 20.

[0041] The underlying soil in estuary areas is mostly loose sand, silt, or soft cohesive soil with a high void ratio and high water content. Vibratory compaction and dynamic compaction are highly suitable for these types of foundations. Vibratory compaction applies cyclic vibration loads to the foundation soil using vibratory equipment, causing loose soil particles to rearrange, compacting pores, reducing the void ratio, and increasing soil density. It is particularly suitable for sandy and silty soil foundations, significantly improving the foundation's resistance to liquefaction and bearing capacity. It has high construction efficiency, minimal disturbance to the foundation, and is suitable for large-area estuarine foundation treatment. Dynamic compaction, on the other hand, generates strong impact and vibration on the foundation soil through impact action, causing instantaneous consolidation and compaction. It can effectively eliminate foundation heterogeneity, improve the overall bearing capacity and deformation resistance of the foundation, and is particularly suitable for areas with weak soil layers and insufficient foundation bearing capacity. It has good adaptability to the complex foundation conditions of estuary areas.

[0042] In some embodiments, structural reinforcement of high-risk erosion areas includes: in high-risk erosion areas, installing at least one of riprap, gabion baskets, and reinforced concrete piles 40 to reinforce the high-risk erosion areas.

[0043] Three reinforcement methods can be flexibly selected or combined according to the actual situation to form a targeted protection plan. **Rockfill and Masonry:** This method involves manually placing stones and then tightly embedding them to form a stable masonry structure. It is characterized by simple construction, low cost, and good permeability, making it suitable for areas with strong hydrodynamic forces but good foundation conditions, such as scour pits and the toes of embankments. It effectively resists direct scouring by water flow, while the gaps between the stones allow for drainage and pressure reduction, preventing seepage damage. **Gabion:** These are woven from galvanized steel wire into mesh cages, filled with stones to form a flexible protective structure. They have good flexibility and permeability, adapting to uneven foundation settlement and possessing strong scour resistance. They are suitable for high-risk areas with weak foundations and prone to deformation, such as weak foundation zones. The flexibility of the gabions disperses the impact energy of the water flow, preventing structural damage caused by localized stress concentration. Furthermore, gabions facilitate plant "landing," allowing plants to play an ecological slope stabilization role, thereby effectively enhancing the stability of riverbed slopes. Reinforced concrete piles (40): By inserting the piles deep into the foundation, a rigid support structure is formed, which can significantly improve the bearing capacity and erosion resistance of the foundation. It is suitable for critical weak points with strong water erosion and extremely poor foundation stability, such as the base of groynes and the corners of embankments. The piles can penetrate deep into stable soil layers, providing reliable support for the superstructure and preventing the foundation from being eroded away. The combined use of these three methods can form a composite protection system, comprehensively adaptable to high-risk areas with different erosion intensities and geological conditions, improving the targeting and effectiveness of the protection plan.

[0044] In some embodiments, riprap is installed in high-risk erosion areas and fixed in the foundation by reinforced concrete piles 40. Traditional riprap masonry structures are prone to problems such as rock displacement and scouring under long-term hydrodynamic action, requiring frequent maintenance and re-laying, resulting in high maintenance costs. However, the riprap structure fixed by reinforced concrete piles 40 significantly improves overall stability, making it less prone to rock displacement, reducing the workload and cost of later maintenance, extending the service life of the protective structure, and improving the long-term benefits of the project. The arrangement of the piles can divide the riprap into multiple independent protective units. Even if local rock displacement occurs, it will not affect the stability of the entire structure, improving the fault tolerance of the protective system.

[0045] In some embodiments, a reinforced and filter composite material layer 30 is provided on at least a portion of the riprap, and the end of the reinforced and filter composite material layer 30 away from the embankment 12 is fixed by reinforced concrete piles 40. The reinforced filter layer covering the riprap integrates the riprap structure with the subsequent protective layer, avoiding structural discontinuities at the interface and forming a continuous and complete protective system, eliminating weak points prone to concentrated water scouring. The riprap layer provides a solid supporting base for the reinforced filter layer, preventing tearing due to uneven foundation settlement. Simultaneously, the rough surface of the riprap increases friction with the reinforced layer, further enhancing its stability. The fixing effect of the piles restricts the displacement of the reinforced filter layer, preventing overall sliding or end lifting under water flow, ensuring the integrity and continuity of the reinforced layer, and enabling it to continuously perform its reinforcement and filter functions.

[0046] In some embodiments, the reinforced and filter composite material layer 30 includes at least one of a three-dimensional geonet and a high-strength woven geotextile. The three-dimensional geonet and the high-strength woven geotextile have complementary performance characteristics and can be used alone or in combination according to actual needs to form a composite reinforced filter layer with superior performance. The high-strength woven geotextile has extremely high tensile strength and good permeability, mainly functioning as reinforcement and filter. Its high tensile strength can effectively resist the tensile force of the soil, improve the overall anti-sliding stability of the slope, and prevent soil sliding failure. The three-dimensional geonet has a three-dimensional structure with high porosity, providing good energy dissipation and drainage functions. It also provides embedding for the subsequent riprap filter layer, improving the overall stability of the filter layer. Its three-dimensional structure also provides channels for plant root growth, which is beneficial for the establishment and growth of salt marsh plants. The high tensile strength of high-strength woven geotextiles effectively resists the tensile forces of the soil, enhancing the overall anti-sliding stability of the slope and preventing soil sliding failure. Simultaneously, its excellent permeability allows for the drainage of seepage water from the foundation, reducing pore water pressure and preventing seepage-induced damage such as piping and soil erosion. When the two materials are used in combination, the woven geotextile acts as the bottom layer, providing filtration and reinforcement, while the three-dimensional geonet acts as the top layer, providing energy dissipation, embedding, and ecological functions. This forms a fully functional composite reinforced filter layer, significantly improving the performance of the protection system.

[0047] In some embodiments, the ecological restoration and reconstruction method further includes: Step S800: Sequentially install a filter layer, a stabilizing layer, and a wave-resistant energy dissipation layer on the reinforced and filter composite material layer 30.

[0048] Based on the reinforced and filter composite material layer 30, a filter layer, a stabilizing layer, and a wave-resistant energy dissipation layer are further added, forming a four-level progressive protection system. Each layer undertakes a specific function, working synergistically to significantly improve the overall protective capability of the revetment structure. The bottom reinforced filter layer: performs reinforcement, filtration, and drainage functions, ensuring foundation stability and preventing seepage damage. The filter layer: further refines the filtration function, blocking the loss of foundation soil particles while draining seepage water, protecting the bottom reinforcement material from siltation. The stabilizing layer: as the main framework of the revetment structure, provides overall stability, resists the impact of water flow, and prevents structural deformation or instability. The wave-resistant energy dissipation layer: directly faces the impact of incident waves and water flow, reducing hydrodynamic energy through the embedding and energy dissipation of blocks, lowering the impact intensity on the underlying structural layers. This multi-level progressive protection system achieves layer-by-layer energy dissipation and protection, significantly improving the scour and wave resistance of the revetment structure and ensuring the long-term stability of the project.

[0049] The three-layered facing structure, formed by the layered arrangement of graded boulders, creates a porous and highly permeable structural system. The pores between the layers of boulders create interconnected drainage channels, ensuring free water exchange and preventing the rigid structure from obstructing ecological connectivity. The porous structure provides habitats for benthic organisms and pathways for the root growth of salt marsh plants, facilitating the establishment and succession of biological communities and promoting ecosystem restoration. Simultaneously, the layered, embedded boulders structure possesses excellent overall stability, resisting strong hydrodynamic forces and meeting engineering protection requirements, thus achieving a synergy between structural stability and ecological function.

[0050] In some embodiments, the filter layer comprises crushed stone with a particle size of 5cm to 15cm, the stabilizing layer comprises boulders with a particle size of 15cm to 30cm, and the wave-resistant and energy-dissipating layer comprises large boulders or artificial irregularly shaped blocks with a particle size of 30cm to 50cm. The filter layer uses crushed stone with a particle size of 5cm to 15cm, which has a small particle size and moderate porosity, effectively preventing the loss of foundation soil particles while allowing water to drain freely, preventing seepage damage, avoiding clogging of the underlying reinforcement material, and ensuring the long-term effectiveness of the filter function. The stabilizing layer uses boulders with a particle size of 15cm to 30cm, which has a moderate particle size and good interlocking performance, forming a stable overall skeleton structure to resist the shearing effect of water flow, preventing the facing structure from sliding or collapsing. At the same time, the medium-sized boulders can disperse the impact energy of water flow, reducing the impact on the underlying filter layer. The wave-resistant energy dissipation layer uses large stones or artificial irregularly shaped blocks with a particle size of 30cm-50cm. The large particle size and high self-weight result in strong erosion resistance. It can directly break and reduce the energy of incident waves, thereby reducing the impact intensity of waves on the underlying structure. At the same time, the energy dissipation effect of large stones or irregularly shaped blocks is better, which can effectively resist strong water flow and prevent them from being washed away.

[0051] In some embodiments, after terrain preparation, reinforcing materials can be laid directly, covered with a layer of natural gravel of a single particle size, and local plant seeds and soil microorganisms can be implanted using hydroseeding technology. This can quickly initiate vegetation succession and is suitable for low-energy protected areas or as a buffer zone for core restoration areas.

[0052] In some embodiments, the ecological restoration and reconstruction method further includes: Step S910: Determine the tidal flat area (sand ridge tide) 50 in the ecological restoration area; Step S920: Set up a hidden dam 11 on the side of the tidal flat area 50 away from the riverbank.

[0053] By setting up a hidden dam 11 along the path of the incident waves, wave energy can be broken up and reduced in advance, significantly reducing the direct impact intensity of waves on the downstream shoreline, reducing the driving force for shoreline erosion, and creating conditions for shoreline siltation and stability. At the same time, the hidden dam 11 can guide the direction of tidal currents, reduce the concentrated scouring of local shorelines by the main current, promote the deposition of suspended sediment in the area behind the dam, and gradually shape a siltation-type tidal flat landform, realizing a landform restoration model that combines engineering guidance and natural shaping.

[0054] In some embodiments, the ecological restoration and reconstruction method further includes: Step S1100: Identify areas of severe water turbulence within the ecological restoration area; Step S1200: Install energy dissipation structures in areas of intense water turbulence.

[0055] Energy dissipation structures can directly break up and reduce the turbulent energy of water flow, lowering the impact intensity of water flow on the foundation and revetment structure, preventing the foundation from being eroded and hollowed out, and avoiding localized structural damage. At the same time, energy dissipation structures can adjust the direction of water flow, reducing the concentrated scouring of local shorelines by the main flow, reducing the destructive effect of turbulence on the engineering structure, eliminating weak points in the project, and ensuring the overall stability of the entire restoration system.

[0056] The unique structures of irregularly shaped blocks, such as the Twisted King and four-legged hollow cubes, can break up incident waves, creating a complex turbulent field that significantly reduces wave energy and lowers the impact intensity on the underlying structure. The interlocking and embedding of the blocks form a stable overall protective system, preventing them from being washed away by the water flow. Simultaneously, the high weight of the blocks helps them withstand strong water scouring, enhancing the erosion resistance of the protective structure. The use of these specialized energy-dissipating structures significantly improves the protective effect in areas of intense water turbulence, ensuring the long-term stability of the engineering structure.

[0057] The energy-dissipating structures are mostly porous, highly permeable, irregularly shaped blocks. The pores between the blocks provide habitats for benthic organisms and channels for water exchange and sediment deposition, avoiding the obstruction of ecological connectivity by rigid structures. Furthermore, energy dissipation protection is applied only to areas with intense water turbulence, rather than the entire shoreline being hardened, thus preserving the natural ecological environment of low-energy zones to the greatest extent possible. This provides space for the establishment and succession of biological communities, achieving a balance between protective performance and ecological function. Additionally, native mollusks and algae or salt-tolerant plant seedlings can be inoculated into the pores of the rocks to accelerate the establishment of biological communities.

[0058] In some embodiments, geosynthetic materials may be replaced with natural fiber mats (coconut fiber, jute mats) or biodegradable polymer grids to further enhance initial eco-friendliness.

[0059] In some embodiments, the soil and rock layer may be partially replaced with eco-concrete blocks, recycled aggregate from waste concrete, or a mixture of shell sand to impart specific pH-regulating or bio-attachment-promoting functions.

[0060] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

Claims

1. A method for ecological restoration and reconstruction of river estuaries, characterized in that, include: Determine ecological restoration areas at river estuaries; Determine the average low tide level and average high tide level of the ecological restoration area; Remove the surface silt and soft soil layer in the ecological restoration area, and carry out compaction and reinforcement treatment on the underlying riverbed foundation; High-risk erosion areas were identified within the ecological restoration area located below the average low tide level; Structural reinforcement treatment was carried out on the high-risk erosion areas; A hidden dam is constructed below the average low tide level in the ecological restoration area. A dike shall be constructed at the location corresponding to the average high tide level in the ecological restoration area. A reinforced and filter composite material layer is installed on the foundation between the hidden dam and the embankment in the ecological restoration area; The reinforced and filter composite material layer is provided on the foundation of the high-risk erosion area and on at least a portion of the area that has undergone the structural reinforcement treatment.

2. The ecological restoration and reconstruction method according to claim 1, characterized in that, The underlying riverbed foundation was compacted and reinforced, including: Vibratory compaction or dynamic compaction treatment is carried out on the underlying riverbed foundation.

3. The ecological restoration and reconstruction method according to claim 1, characterized in that, Structural reinforcement treatment of the high-risk erosion area includes: In the high-risk erosion area, at least one of the following is used for structural reinforcement: riprap, gabion baskets, and reinforced concrete piles.

4. The ecological restoration and reconstruction method according to claim 3, characterized in that, The riprap is placed in the high-risk erosion area and fixed in the foundation by the reinforced concrete piles.

5. The ecological restoration and reconstruction method according to claim 4, characterized in that, The reinforced and filter composite material layer is provided on at least a portion of the riprap, and the end of the reinforced and filter composite material layer away from the dam is fixed by the reinforced concrete pile.

6. The ecological restoration and reconstruction method according to claim 1, characterized in that, The reinforced and filter composite material layer includes at least one of a three-dimensional geonet and a high-strength woven geotextile.

7. The ecological restoration and reconstruction method according to claim 1, characterized in that, The ecological restoration and reconstruction method also includes: A filter layer, a stabilizing layer, and a wave-resistant energy dissipation layer are sequentially disposed on the reinforced and filter composite material layer.

8. The ecological restoration and reconstruction method according to claim 7, characterized in that, The filter layer comprises crushed stone with a particle size of 5cm to 15cm, the stabilizing layer comprises boulders with a particle size of 15cm to 30cm, and the wave-resistant and energy-dissipating layer comprises large boulders or artificial irregularly shaped blocks with a particle size of 30cm to 50cm.

9. The ecological restoration and reconstruction method according to claim 1, characterized in that, The ecological restoration and reconstruction method also includes: The tidal flat area above the ecological restoration area was identified; The hidden dam is constructed on the side of the tidal flat area away from the riverbank.

10. The ecological restoration and reconstruction method according to claim 1, characterized in that, The ecological restoration and reconstruction method also includes: Identify areas of severe water turbulence within the ecological restoration zone; An energy dissipation structure is installed in the area of ​​intense water flow turbulence.

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