Primary salt marsh wetland toughness improving method based on corridor type spartina alterniflora ecological regulation and control

Abstract

The invention relates to the technical field of coastal zone ecological restoration, and particularly discloses a method for improving the toughness of a primary salt marsh wetland based on corridor type spartina alterniflora ecological regulation and control. According to the method, an intertidal zone salt marsh wetland in which spartina alterniflora and native plants coexist is taken as an object, a hydrological communication pattern of the intertidal zone salt marsh wetland is identified, according to a regulation and control framework of'design-simulation-monitoring-evaluation-optimization ', a vegetation-free corridor in a tidal current dominant direction is designed, different corridor widths and spatial layouts are set, and the vegetation-free corridor in the tidal current dominant direction is established. The hydrological communication recovery and sediment communication efficiency is evaluated in a mode of combining model simulation and field monitoring, and then gallery parameters are optimized to obtain an optimal mode; on the basis, self-organization development and toughness improvement of the primary wetland are promoted. According to the method, smooth cordgrass corridor control and wetland sediment communication regulation are combined initiatively, a feedback optimization regulation and control framework based on sediment communication efficiency quantification is constructed, and a low-cost and self-regulation ecological engineering new scheme integrating invasive species treatment and original wetland toughness improvement is formed.

Description

Technical Field

[0001] This invention relates to the field of coastal ecological restoration technology, and in particular to a method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation. Background Technology

[0002] Salt marshes, located in the terrestrial-marine ecotone, serve as a crucial barrier for coastal ecological security, playing a vital ecological role in mitigating storm surges, sequestering carbon, and maintaining biodiversity. In recent years, influenced by global warming, the rate of sea-level rise has accelerated significantly, leading to increased flooding and system degradation in intertidal salt marshes. The resilience of salt marsh ecosystems depends on a feedback loop between hydrodynamics, sedimentation, and vegetation: tidal forces transport suspended sediment inland, where vegetation slows the flow, causing sediment deposition and raising the tidal flat base to match the sea-level rise and maintain a suitable environment for vegetation. Vegetation growth further promotes sediment accumulation, enhancing erosion resistance, thus forming a self-sustaining mechanism based on biophysical feedback. If this feedback loop is disrupted, the wetland will struggle to maintain dynamic equilibrium, leading to a decline in system resilience.

[0003] Spartina alterniflora, a perennial herb native to the Atlantic coast of North America, possesses high stress tolerance and environmental shaping capabilities, earning it the nickname "ecosystem engineer." It is a typical invasive species in my country's coastal salt marshes. In invasive areas, Spartina alterniflora can alter local topography and hydrological connectivity through its dense rhizomes and siltation-promoting effects, weakening tidal energy transport. In typical salt marshes such as the Yellow River Delta, its invasion has led to dynamic attenuation and local siltation, creating a dam-basin geomorphological pattern, disrupting original water and sediment transport pathways, causing inland salt marsh subsidence, water stagnation, and degradation of native vegetation, significantly weakening the structural and functional resilience of salt marshes.

[0004] Existing technologies primarily target the control of Spartina alterniflora or the restoration of vegetation in salt marshes, but these two approaches are often treated separately, making it difficult to achieve a holistic restoration of ecological functions. For example, previous studies have explored methods combining mowing and tillage, or mowing and brackish water irrigation, which can effectively suppress the growth and reproduction of Spartina alterniflora, but these engineering effects may hinder the natural recovery of native species. Some scholars have also proposed a bio-physical control method combining physical shading and biological substitution to control Spartina alterniflora, but this often uses mangroves as substitute plants, which is not suitable for salt marsh wetlands. Furthermore, the restoration of vegetation in salt marshes often employs methods such as artificial planting, micro-topography modification, and biogrid materials to improve local habitats and promote seedling establishment, but these small-scale interventions cannot address the systemic problem of impaired overall connectivity after invasion.

[0005] Therefore, there is an urgent need to develop a new method that can control Spartina alterniflora while restoring the "dynamic-sediment-vegetation" feedback cycle of salt marsh wetlands, so as to achieve the synergistic goal of controlling invasive species and improving the resilience of native wetlands, thereby restoring the self-sustaining and self-regulating capacity of the salt marsh wetland system. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies, this invention provides a method for enhancing the resilience of native salt marsh wetlands based on corridor-style Spartina alterniflora ecological regulation. This method proposes a regulation framework of "design-simulation-monitoring-evaluation-optimization". By combining model simulation with on-site monitoring, it constructs and optimizes the pattern of vegetation-free corridors. While achieving Spartina alterniflora control, it can significantly improve the wetland sediment connectivity efficiency, thereby promoting wetland self-organization and enhancing system resilience.

[0007] This invention is achieved through the following technical solution: A method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation includes the following steps: (1) Select intertidal salt marsh wetlands where Spartina alterniflora and native plants grow as the target; (2) Identify the hydrological connectivity pattern of salt marsh wetlands, clarify the dominant tidal current direction in the sea-land dimension and the tidal channel-tidal flat dimension, construct the model domain and divide the space into grids; (3) Based on the regulatory framework of “design-simulation-monitoring-evaluation-optimization”, construct and optimize the pattern of vegetation-free corridors, restore hydrological connectivity, and improve sediment connectivity; (4) In the design phase, select a non-vegetated corridor layout along the dominant trend direction and set a series of corridor and vegetation spacing parameters. (5) In the simulation phase, a salt marsh biogeomorphic model coupled with vegetation feedback effect is constructed using hydrodynamic geomorphology modeling tools to simulate the hydrological connectivity and sediment connectivity conditions of the above-mentioned corridor width and interval distance combination scenario. The vegetation feedback effect is quantified by an experimental empirical formula. (6) In the monitoring phase, a corridor-type Spartina alterniflora removal control experiment was carried out in a salt marsh wetland. The biomass of Spartina alterniflora was removed by a combination of mechanical and manual mowing to create a vegetation-free corridor connecting open water bodies and native plant areas. The hydrological connectivity and sediment connectivity characteristics of the corridor were monitored at multiple points. (7) In the assessment phase, the efficiency of hydrological connectivity restoration and sediment connectivity is assessed based on the flow velocity and spatial sediment deposition patterns of different corridor treatment groups. (8) In the optimization stage, the evaluation results of different corridor scenarios are compared, and the corridor parameters with high sediment connectivity efficiency and revenue surplus are selected to obtain a corridor optimization model that is conducive to improving wetland resilience. (9) Based on the corridor optimization model obtained from the above regulatory framework, carry out regional Spartina alterniflora removal regulation to improve the sediment connectivity and landform development of inland native wetlands and promote the self-organized evolution and resilience enhancement of salt marshes.

[0008] A more preferred technical solution of the present invention is as follows: In step (1), the salt marsh wetland is a system that is significantly affected by tidal fluctuations but less affected by wave erosion. The sediment carried by the tide is an important source of material for the development and succession of the wetland.

[0009] In step (2), the hydrological connectivity pattern includes the open sea, tidal channel network and tidal flat flow pattern. Along the hydrological connectivity intensity gradient, the wetland landscape composed of Spartina alterniflora and native plants has a zonal distribution feature. The model domain takes the tidal channel-tidal flat composite wetland as the core research area and extends to the shallow sea area and to the boundary of artificial structures. A spatially non-uniform structural grid is constructed in the model domain, with a grid size of 4-160m.

[0010] In step (3), the layout of the vegetationless corridor is to create a vegetationless corridor connecting the open water body (including the tidal channel system) and the native plant area along the dominant tidal direction, so as to restore the hydrological connectivity of the inland salt marsh to the greatest extent.

[0011] In step (4), the width parameter is set based on a 1:1 ratio between the corridor and vegetation, and a series of combinations of increasing and decreasing the corridor width are further set to explore the feedback effect of vegetation pattern on tidal dynamics; for the model scenario setting, the corridor width is increased (greater than 20m) to simulate the system response at the landscape scale; for the field monitoring setting, the corridor width is reduced (less than 20m) to simulate the system response at the local scale.

[0012] In step (5), the initial conditions, boundary conditions, and process parameters required for model construction are set according to the characteristics of the wetland system under study. The tidal rise and fall process is simulated by solving the depth-averaged NS equation. Among them, the ocean boundary is driven by astronomical tides and is defined by setting the amplitude and phase parameters of eight major tidal constituents (i.e., M2, S2, K1, O1, N2, K2, P1, Q1). The tidal constituent parameters are obtained by harmonic analysis of the tidal level data of the regional tidal station. The tidal harmonic analysis is carried out with the help of the T-tide tool. The sediment transport process is characterized by the convection-diffusion equation, and the geomorphic changes caused by sediment deposition or erosion are calculated by adding source and sink terms to the equation. The sediment concentration and parameters are set according to the regional measured data, and the other parameters are taken as default values.

[0013] A further preferred technical solution is that the feedback effect of vegetation on the flow field is simulated by adding a dissipation term to the momentum equation. Based on the tidal fluctuation characteristics of the coastal salt marsh, the vegetation feedback effect considers both the exposed and submerged states of the vegetation; the specific formula is as follows: In the vegetation exposure scenario (h < h) ν That is, the water surface is below the vegetation canopy. C=C b , λ=C D ×n; In the scenario of vegetation submersion (h > h) ν That is, the water surface is above the vegetation canopy. , , ; In the formula, C and λ represent the substrate roughness and turbulent kinetic energy dissipation caused by vegetation, respectively. b For the surface roughness, C D Here, is the vegetation blocking coefficient, n is the plant density (n = m * D, where m is the plant density and D is the plant basal diameter), h and h v Let represent the water depth and the vegetation canopy height, respectively; j is the Von Karman constant (0.41); and g is the acceleration due to gravity. In step (6), after the biomass of Spartina alterniflora is cut and removed, the stubble height at the bottom should not exceed 5 cm to minimize its resistance to water flow; hydrological connectivity monitoring is conducted by measuring the tidal current velocity within the channel using a current meter; sediment deposition monitoring is performed by determining the sediment deposition rate of the tidal flat using a sedimentation disc; the sedimentation disc consists of an unobstructed flat plate and removable filter paper, and the deposition rate is obtained by calculating the change in the net weight of the dried filter paper and the area conversion at the beginning and end of the monitoring period. The calculation method is as follows: , In the formula, Y ij It is a processing group i In position j Sediment deposition rate (g / m 2 day), W ij It is a specific time period T Internal processing group i In position j The amount of sediment deposited (after drying, g). S It is the area of ​​the filter paper (m²) 2 ).

[0014] Further preferred, the sedimentation disk monitoring cycle covers at least one complete tidal cycle, approximately 14 days; the sedimentation disk monitoring is deployed at unequal intervals along the environmental gradient, with denser monitoring near the shore and sparser monitoring inland, while covering landscape types such as nearshore areas, Spartina alterniflora areas, and native plant areas.

[0015] In step (7), sediment connectivity is assessed by evaluating the sediment connectivity efficiency of the corridor through the sediment deposition rate at each monitoring point along the environmental gradient. The sediment connectivity efficiency of the corridor is the reciprocal of the slope coefficient of sediment deposition attenuation in the corridor. The slope coefficient of sediment deposition attenuation in the corridor is obtained by semi-logarithmic fitting of the sediment deposition rate and the distance from the open water body. The calculation formula is as follows: , , In the formula, SCE i It is a corridor group i The efficiency of sediment connectivity. β i It is a corridor group i The slope coefficient of sediment deposition attenuation is derived from the sediment deposition rate ( Y i ) and distance from open water body ( X i The result was obtained by performing a semi-logarithmic fit.

[0016] In step (9), the removal and regulation of Spartina alterniflora involves regular removal of Spartina alterniflora from May to September each year after the initial cutting and removal, in order to maintain the stability of the corridor morphology. Depending on the growth of its new seedlings, it is repeatedly and continuously cut every half month or month until the flowering period ends and there are no more large-scale new seedlings.

[0017] The beneficial technical effects of the present invention are as follows: (1) Restore hydrological connectivity and promote the self-organization and development of the system. By creating vegetation-free corridors, the free ebb and flow of tides can be restored, solving the hydrological connectivity blockage problem caused by the barrier effect of Spartina alterniflora; improving sediment transport efficiency, promoting vertical accumulation of inland wetlands, reducing the risk of degradation caused by sea-level rise, and enhancing the elevation stability and resistance to disturbance of salt marshes.

[0018] (2) Management costs are controllable and it has a self-sustaining function. Compared to the strategy of mechanically removing Spartina alterniflora and requiring long-term maintenance, this invention mainly relies on corridor setup and initial dynamic cleaning to maintain the effect, with low investment costs. Through a reasonable pattern of vegetation and corridors, the feedback effect of the remaining vegetation can be stimulated, maintaining strong hydrological connectivity in the corridor area, inhibiting the establishment of new Spartina alterniflora seedlings, and achieving self-sustaining of the corridor morphology.

[0019] (3) Balancing the control of invasive species with the enhancement of ecological functions This method achieves spatial control of Spartina alterniflora through ecological corridor structures, which not only weakens its hydrological blocking impact but also leverages the carbon sequestration function of the retention area. At the same time, the improvement of sediment connectivity promotes habitat quality and native vegetation resilience, which helps to achieve synergistic enhancement of multiple functions such as wetland hydrological regulation, habitat supply, and carbon storage. Attached Figure Description

[0020] The invention will now be further described with reference to the accompanying drawings.

[0021] Figure 1 A schematic diagram showing the changes in the layout and sediment connectivity before and after corridor-style remediation; Figure 2 Construction of a biogeomorphological model of the Yellow River Delta salt marsh wetland and measurement point map; Figure 3 Comparison images for verifying the biogeomorphological model of the Yellow River Delta salt marsh wetland; Figure 4 Schematic diagram of the scenario configuration for a vegetation-free corridor and the simulation results of hydrological and sediment connectivity. Figure 5 A graph showing the relationship between sediment deposition rate and distance from tidal channel for different corridor widths; Figure 6 A comparison chart showing the improvement in sediment connectivity efficiency under different corridor widths. Detailed Implementation

[0022] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0024] The method of this invention focuses on intertidal salt marsh wetlands where Spartina alterniflora and native plants grow. Along the dominant tidal direction, the aboveground biomass of Spartina alterniflora is removed to create vegetation-free corridors connecting open water bodies (including tidal channels) and native plant areas. By designing vegetation-free corridor scenarios of different widths, based on model simulation and field monitoring data, the hydrological connectivity restoration and sediment connectivity efficiency of different corridor scenarios are evaluated to obtain an optimized pattern of vegetation-free corridors. This allows for regional regulation and management to improve sediment accumulation in inland salt marshes and promote wetland self-organization and resilience.

[0025] The implementation site of this invention is located in the salt marsh wetland on the north bank of the Yellow River Delta in Dongying City, Shandong Province. This area is affected by irregular semi-diurnal tides, with a tidal range of approximately 0.7-1.3 meters and relatively weak wave activity, belonging to the siltation-type tidal flat driven by tides. A tidal channel-tidal flat composite wetland significantly affected by tidal activity was selected as the experimental area. This area exhibits a clear hydrological connectivity gradient, with the ebb and flow of the tide perpendicular to the tidal channel being the dominant feature of hydrological connectivity. From the tidal channel inland, there are successively distributed Spartina alterniflora invasion zones and native Suaeda salsa communities. The Spartina alterniflora invasion leads to a dike-basin structure along the tidal channel-tidal flat dimension, i.e., excessive siltation near the shore forms a raised landform, while the transition zone and Suaeda salsa area form low-lying waterlogged areas, resulting in vegetation degradation (see...). Figure 1 (a)).

[0026] The implementation of this invention follows a control framework of "design-simulation-monitoring-evaluation-optimization." The implementation area is a tidal channel-tidal flat composite wetland. The rise and fall of the tide on the flat surface is mainly achieved through tidal channel flooding and backflow. Therefore, the direction of the unvegetated corridor is designed to be perpendicular to the tidal channel. A regional salt marsh biogeomorphological model is constructed based on Delft3D. The built-in Trachytope module quantifies the turbulent kinetic energy dissipation caused by the presence of *Spartina alterniflora* to reflect its flow obstruction effect. From May to September, the inventors carried out biomass removal of *Spartina alterniflora* along the direction perpendicular to the tidal channel (i.e., the dominant tidal direction) to construct an unvegetated corridor connecting the tidal channel system and the *Suaeda salsa* wetland (see...). Figure 1 (b) and conduct hydrological connectivity and sediment connectivity monitoring in order to assess and optimize the corridor pattern.

[0027] A salt marsh biogeomorphic model simulating the feedback effect of Spartina alterniflora was constructed using Delft3D. Tidal fluctuations were simulated by solving the depth-averaged Navier-Stokes equations, and sediment transport was characterized by convection-diffusion equations. Source and sink terms were added to the equations to calculate geomorphic changes caused by sediment deposition or erosion. Since the regional sediment is predominantly fine-grained cohesive sand, the PK formula was used to calculate sediment deposition and erosion.

[0028] The model domain takes the tidal channel-tidal flat composite wetland as the core research area, and extends seaward to the shallow sea area and landward to the boundary of artificial structures, in order to reduce the impact of boundary effects on the dynamic sediment simulation of the core area. Figure 2 To balance spatial resolution and computational efficiency, a non-uniform structured mesh with a mesh size of 4-160m was selected.

[0029] Using observational data on tidal levels, current velocities, and sediment in the study area (see...) Figure 2 The model was validated and verified using the following methods: time-series tidal level data from tidal channel stations (L1, L2) were used for water level verification; time-series flow velocity and sediment data from the offshore station (S) and tidal channel station (L2) were used to verify the flow field and sediment simulation results; and spatial sedimentary erosion data from the Spartina alterniflora (L3 green dot) and Suaeda salsa (L3 orange dot) tidal flats were used to verify the geomorphological simulation. The results show that the model can well characterize the time-series features of the regional dynamic field and sediment field. Furthermore, the tidal flat sedimentary erosion verification demonstrates that the model can effectively simulate spatial geomorphological changes and vegetation feedback effects. Figure 3 Therefore, the model has been validated and can be used for subsequent scenario simulations. The validation evaluation table for the Yellow River Delta salt marsh wetland biogeomorphology model is as follows: Note: The smaller the RMSE, the better the simulation result; Skill score > 0.5 indicates a very good simulation result, and 0.2 < Skill score < 0.5 indicates a good simulation result.

[0030] When simulating the Spartina alterniflora corridor pattern, a scenario was set up where the corridor width and vegetation strip width were proportional. Two calculation cells (8 meters) were used as the baseline width, and the corridor / vegetation width ratios were set to gradients of 2:8, 2:4, 2:2, 4:2, and 8:2. Figure 4 This study simulated the dynamic patterns and geomorphological changes of tidal flats driven by alternating tidal and neap tides. The results showed that increasing the width of the cutting corridor enhanced the hydrological connectivity of inland wetlands; however, in excessively wide corridors (e.g., the 8:2 scenario), inland wetlands experienced excessive surface erosion due to overly strong dynamics. Therefore, a corridor / vegetation zone width of no more than 1:1 can maintain relatively good hydrological and sediment connectivity.

[0031] On-site mowing of Spartina alterniflora uses a combination of a four-stroke mower and manual mowing, keeping the bottom stubble no more than 5 centimeters to reduce water flow resistance and slow down the regeneration rate.

[0032] Spartina alterniflora mowing is carried out in stages and at different frequencies. During the rapid growth period from May to July, it is mowed every half month; during the post-flowering stabilization period from August to September, it is mowed monthly. Mowing during the flowering period can effectively block the sexual reproduction of Spartina alterniflora and limit its invasion and expansion in the following year. After that, almost no new Spartina alterniflora seedlings are produced, thus maintaining the corridor pattern.

[0033] Set up a gradient of corridor pattern widths. Based on the area, select a cut corridor width and a vegetation spacing width of 4 meters as the baseline scenario. Expand the corridor width scenario and set up Spartina alterniflora cut corridor scenarios with widths ranging from 1 to 20 meters to compare and optimize the corridor width.

[0034] After Spartina alterniflora was cut and removed, the hydrological connectivity was characterized by monitoring the tidal current velocity under different width scenarios by deploying current meters in the middle of the corridor. The results showed that the flood and ebb current velocities of the corridor were the highest under the medium width condition. After Spartina alterniflora was cut and removed, sediment deposition rates at different locations on the tidal flat were monitored by deploying sedimentation disks of varying density along the tidal channel-tidal flat dimension. The results showed that increasing the corridor width could increase the total sediment deposition on the tidal flat, but under medium width conditions, it was more conducive to sediment transport and distribution inland (see...). Figure 5 ).

[0035] Based on the deposition rate and distance from the tidal channel at spatial locations, the improvement in sediment connectivity efficiency for different corridor width treatment groups was estimated. The results showed that, compared to the uncontrolled control group, adding corridors could improve sediment connectivity efficiency by 291%-466%, with the 4m wide corridor exhibiting the highest efficiency (see...). Figure 6 The table below shows the comparison data of sediment connectivity efficiency and improvement ratio under different corridor widths: By comparing and selecting, an optimal configuration scheme for the non-vegetation corridor in the area was selected (the corridor / vegetation belt width should not exceed 1:1, and the suitable corridor width is 4-20 meters).

[0036] The method of this invention has the advantages of high efficiency, low cost, scientific approach, and precision, and can be applied to Spartina alterniflora control and wetland restoration projects at different scales. When expanding its application, appropriate mechanical removal methods can be selected according to the spatial scale, tidal environment, and sediment conditions of the treatment area. Corridor configuration pattern optimization can be carried out by combining model simulation with on-site control and monitoring, forming an ecological regulation model that combines invasive species control and wetland resilience enhancement.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation, characterized by including: The following steps were taken: (1) Selecting intertidal salt marsh wetlands where Spartina alterniflora and native plants grow as the object; (2) Identifying the hydrological connectivity pattern of the salt marsh wetlands, clarifying the dominant tidal current direction in the sea-land dimension and the tidal channel-tidal flat dimension, constructing the model domain and dividing the space into grids; (3) Constructing and optimizing the unvegetated corridor pattern according to the "design-simulation-monitoring-evaluation-optimization" control framework, restoring hydrological connectivity, and improving sediment connectivity; (4) In the design phase, selecting the unvegetated corridor layout along the dominant tidal current direction and setting a series of corridor and vegetation interval width parameters; (5) In the simulation phase, constructing a salt marsh biogeomorphological model coupled with vegetation feedback effect using hydrodynamic geomorphology modeling tools, simulating the hydrological connectivity and sediment connectivity conditions of the above-mentioned corridor width and interval distance combination scenario, and using empirical formulas based on experiments to measure the vegetation feedback effect. Quantification; (6) In the monitoring stage, a field corridor-type Spartina alterniflora removal control experiment was carried out in a salt marsh wetland. The biomass of Spartina alterniflora was removed by a combination of mechanical and manual mowing to create a vegetation-free corridor connecting open water bodies and native plant areas. The hydrological connectivity and sediment connectivity characteristics of the corridor were monitored at multiple points; (7) In the evaluation stage, the hydrological connectivity restoration and sediment connectivity efficiency were evaluated based on the flow velocity and spatial sediment deposition pattern of different corridor treatment groups; (8) In the optimization stage, the evaluation results of different corridor scenarios were compared, and corridor parameters with high sediment connectivity efficiency and high revenue and expenditure surplus were selected to obtain a corridor optimization model that is conducive to improving wetland resilience; (9) Based on the corridor optimization model obtained by the above regulation framework, regional Spartina alterniflora removal regulation was carried out to improve sediment connectivity and geomorphological development in inland native wetlands and promote the self-organized evolution and resilience improvement of salt marshes.

2. The method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation as described in claim 1, characterized in that: In step (1), the salt marsh wetland is a system that is significantly affected by tidal fluctuations but less affected by wave erosion. The sediment carried by the tide is an important source of material for the development and succession of the wetland.

3. The method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation as described in claim 1, characterized in that: In step (2), the hydrological connectivity pattern includes the open sea, tidal channel network and tidal flat flow pattern. Along the hydrological connectivity intensity gradient, the wetland landscape composed of Spartina alterniflora and native plants has a zonal distribution feature. The model domain takes the tidal channel-tidal flat composite wetland as the core research area and extends to the shallow sea area and to the boundary of artificial structures. A spatially non-uniform structural grid is constructed in the model domain, with a grid size of 4-160m.

4. The method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation as described in claim 1, characterized in that: In step (3), the layout of the vegetation-free corridor is to create a vegetation-free corridor connecting the open water body and the native plant area along the dominant tidal direction.

5. The method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation as described in claim 1, characterized in that: In step (4), the width parameter is set based on a 1:1 ratio between the corridor and vegetation, and a series of combinations of increasing and decreasing the corridor width are further set; for the model scenario setting, the corridor width is increased to simulate the system response at the landscape scale; for the on-site monitoring setting, the corridor width is decreased to simulate the system response at the local scale.

6. The method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation as described in claim 1, characterized in that: In step (5), the initial conditions, boundary conditions, and process parameters required for model construction are set according to the characteristics of the wetland system under study. The tidal rise and fall process is simulated by solving the depth-averaged NS equation. Among them, the ocean boundary is driven by astronomical tides and is defined by setting the amplitude and phase parameters of eight major tidal constituents. The tidal constituent parameters are obtained by harmonic analysis of the tidal level data of the regional tidal station. The tidal harmonic analysis is carried out with the help of the T-tide tool. The sediment transport process is characterized by the convection-diffusion equation, and the geomorphic changes caused by sediment deposition or erosion are calculated by adding source and sink terms to the equation. The sediment concentration and parameters are set according to the regional measured data, and the other parameters are taken as default values.

7. The method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation as described in claim 5, characterized in that: The vegetation feedback effect on the flow field is simulated by adding a dissipation term to the momentum equation. Based on the tidal fluctuation characteristics of the coastal salt marsh, the vegetation feedback effect takes into account the exposed and submerged states of the vegetation.

8. The method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation as described in claim 1, characterized in that: In step (6), after the biomass of Spartina alterniflora is cut and removed, the stubble height at the bottom should not exceed 5 cm; for hydrological connectivity monitoring, the tidal current velocity in the corridor is measured using a current meter; for sediment deposition monitoring, the sediment deposition rate of the tidal flat is determined by a sedimentation plate; the sedimentation plate consists of an unobstructed flat plate and removable filter paper, and the deposition rate is obtained by converting the net weight of the dried filter paper and the area at the beginning and end of the monitoring period; the sedimentation plate monitoring cycle covers at least one complete tidal cycle; the sedimentation plate monitoring is deployed at unequal intervals along the environmental gradient, with denser nearshore areas and sparser inland areas, while covering the nearshore area, the Spartina alterniflora area and the native plant area.

9. The method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation as described in claim 1, characterized in that: In step (7), sediment connectivity is assessed by measuring the sediment deposition rate at each monitoring point along the environmental gradient in space. The sediment connectivity efficiency of the corridor is the reciprocal of the slope coefficient of sediment deposition attenuation in the corridor. The slope coefficient of sediment deposition attenuation in the corridor is obtained by semi-logarithmic fitting of sediment deposition rate and distance from open water body.

10. The method for enhancing the resilience of native salt marsh wetlands based on corridor-type Spartina alterniflora ecological regulation as described in claim 1, characterized in that: In step (9), the removal and regulation of Spartina alterniflora involves regular removal of Spartina alterniflora from May to September each year after the initial cutting. Depending on the growth of the new seedlings, the cutting is repeated every half month or month until the flowering period ends and there are no more large-scale new seedlings.

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