A rapid evaluation method and device for vertical hydrological connectivity of coastal wetlands

Abstract

The application discloses a kind of coastal wetland vertical hydrology connectivity rapid evaluation method and device, belong to wetland ecological environment monitoring and assessment technical field, method includes: obtaining pre-soil layer sampling, measured soil moisture content and soil pore water salinity;According to soil moisture content and soil pore water salinity, the connectivity index of vertical hydrology of each sampling point is calculated, and the rapid evaluation of vertical hydrology connectivity is realized by connectivity index;The application can accurately and quickly evaluate the vertical hydrology connectivity of different landforms of wetland by comprehensively considering the characteristics of soil water and salt change.

Description

Technical Field

[0001] This invention relates to a method and apparatus for rapid evaluation of vertical hydrological connectivity in coastal wetlands, belonging to the field of wetland ecological environment monitoring and assessment technology. Background Technology

[0002] Estuarine wetlands, formed by the deposition of river sediments flowing into the sea, are rich in biodiversity and biological resources, playing a crucial role in maintaining biodiversity, geochemical cycles, and pollutant degradation in estuarine regions. Furthermore, the organic carbon generated from primary productivity, a key component of the blue carbon system, can be rapidly buried during sediment deposition, making it significant for mitigating global climate change. However, estuarine wetlands, located at the confluence of rivers and the sea, are vulnerable to the impacts of human activities and climate change. Complex factors such as altered river water and sediment conditions, land reclamation projects, sea-level rise, and storm surges threaten the stability of global estuarine wetlands, leading to shrinking areas and degraded ecological functions. The hydrological processes of wetlands, involving both land and sea, influence the distribution and evolution of habitat factors and control the stability of wetland ecosystems. Therefore, a deep understanding of the hydrological and material transport processes of estuarine wetlands is extremely important for wetland protection and restoration.

[0003] Wetland hydrological connectivity studies the process of transporting matter, energy, and organisms among hydrological cycle elements in wetland ecosystems, reflecting the smoothness of hydrological transmission between different landscape units. It is a crucial application of hydrological connectivity in wetland research, its origins traceable back to the concept of the "river continuum" in 1980. Mainstream wetland hydrological connectivity research largely follows the general approach, focusing primarily on horizontal and vertical connectivity. Vertical hydrological connectivity, a more recent research perspective, stems from studies of surface water and groundwater exchange. It refers to the circulation of matter and energy within the wetland through the exchange of surface and groundwater, evaluating the quality of connectivity accordingly. Vertical hydrological connectivity is reflected in indicators such as soil salinity, directly influencing the shaping of wetland flora and fauna distribution patterns and their resistance to adverse external influences, such as sea-level changes and storm surges.

[0004] Because the concept of wetland vertical hydrological connectivity was proposed relatively late, its evaluation criteria are still incomplete. In 2022, Bai Hongjun et al. constructed a method for quantifying wetland vertical hydrological connectivity by combining soil moisture content with soil structure. However, this method is somewhat cumbersome in practice. Therefore, this paper attempts to propose a simpler and faster method to better serve wetland ecological protection work. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method and device for rapid evaluation of vertical hydrological connectivity in coastal wetlands, overcoming the cumbersome procedures of existing evaluation methods.

[0006] To achieve the above objectives, the present invention is implemented using the following technical solution: In a first aspect, the present invention provides a method for rapid evaluation of vertical hydrological connectivity in coastal wetlands, comprising: Obtain soil moisture content and soil pore water salinity by pre-sampling soil layers; Based on soil moisture content and soil pore water salinity, the vertical hydrological connectivity index of each sampling point is calculated, and the vertical hydrological connectivity is rapidly evaluated through the connectivity index.

[0007] Furthermore, when performing stratified soil sampling, sampling points are selected on different wetland landforms. These sampling points are distributed across different elevation ranges. Shallow soil is drilled at the sampling points, and then stratified sampling is performed. The samples are then sealed on-site to obtain soil samples.

[0008] Furthermore, the method for measuring soil moisture content includes: The moisture content of the soil sample is calculated based on the pre-obtained mass of the container, the total mass of the container and the soil sample, and the total mass of the container and the dried soil sample. The calculation formula is as follows: ; in, The moisture content of the soil sample. For the mass of the container, The total mass of the container and soil sample. This refers to the total mass of the container and the dried soil sample.

[0009] Furthermore, the method for measuring soil pore water salinity includes: Soil pore water salinity was calculated using a saturated extraction method by measuring the salinity and corresponding moisture content of the supernatant. The calculation formula is as follows: ; in, For soil pore water salinity, The ratio of deionized water to soil sample. This refers to the salinity of the supernatant.

[0010] Furthermore, based on soil moisture content and soil pore water salinity, the vertical hydrological connectivity index of each sampling point is calculated using the following formula: ; in For connectivity metrics, The number of measurement points on the soil profile. This represents the average salinity at the measurement points along the soil profile.

[0011] Secondly, the present invention provides a rapid evaluation device for vertical hydrological connectivity of coastal wetlands, comprising: The acquisition module is used to acquire the soil moisture content and soil pore water salinity obtained by pre-sampling and layering of the soil. The evaluation module is used to calculate the vertical hydrological connectivity index of each sampling point based on soil moisture content and soil pore water salinity, and to achieve rapid evaluation of vertical hydrological connectivity through the connectivity index.

[0012] Thirdly, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the methods described above.

[0013] Fourthly, the present invention provides a computer device, comprising: Memory, used to store computer programs / instructions; A processor for executing the computer program / instructions to implement the steps of any of the methods described above.

[0014] Fifthly, the present invention provides a computer program product, including a computer program / instructions that, when executed by a processor, implement the steps of any of the methods described above.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: 1. This invention provides a method and apparatus for rapid evaluation of vertical hydrological connectivity in coastal wetlands. By comprehensively considering the characteristics of soil water and salt changes, it can assess the vertical hydrological connectivity of different landforms in wetlands as accurately and quickly as possible.

[0016] 2. The evaluation indicators and methods provided by this invention are highly targeted and practical, and can provide scientific guidance for the ecological protection, restoration and rational management of wetlands, which helps to improve the stability of wetland ecosystems and their ecological service functions.

[0017] 3. The application of this invention helps to deepen the understanding of the vertical hydrological connectivity mechanism of wetlands, provides new ideas and methods for wetland ecohydrological research, and has important reference value for the research and management of other similar wetlands. Attached Figure Description

[0018] Figure 1 This is a flowchart of a rapid evaluation method for vertical hydrological connectivity of coastal wetlands provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the tidal ditch habitat provided in an embodiment of the present invention. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0020] Example 1: This example introduces a rapid evaluation method for the vertical hydrological connectivity of coastal wetlands, including: Obtain soil moisture content and soil pore water salinity by pre-sampling soil layers; Based on soil moisture content and soil pore water salinity, the vertical hydrological connectivity index of each sampling point is calculated, and the vertical hydrological connectivity is rapidly evaluated through the connectivity index.

[0021] like Figure 1 As shown in this embodiment, the rapid evaluation method for vertical hydrological connectivity of coastal wetlands involves the following steps in its application: (1) Sampling stage Sampling points were selected on different wetland landforms and appropriately distributed at different elevations. A shallow soil layer of 1m was drilled, and samples were taken in layers every 10cm and then sealed on site.

[0022] (2) Soil moisture content measurement In the laboratory, the collected samples are processed in a timely manner to remove impurities such as stones and plant roots from the soil. The samples are gently crushed with a wooden stick to make them into uniform particles. The processed soil samples should be stored in a dry and ventilated environment to prevent moisture absorption or further water loss until the moisture content is measured. Prepare an electronic balance with an accuracy of ±0.001g, a temperature-adjustable constant-temperature oven, a desiccator, and an aluminum box. After cleaning the aluminum box, place it in the oven and dry it at 105℃±2℃ until constant weight, which generally takes 2-4 hours. Then remove it and place it in the desiccator to cool to room temperature. Weigh it using the electronic balance and record the mass (m0) of the aluminum box. Using the ring cutter method, take 5-20g of soil sample from the undisturbed soil sample and place it in an aluminum box. Weigh the sample again and record the total mass (m1) of the aluminum box and soil sample. Place the aluminum box containing the soil sample in a constant temperature oven and dry it at 105℃±2℃ for 6-8 hours to completely evaporate the moisture in the soil. For soils with high organic matter content or special soils, the drying time may need to be appropriately extended, but over-drying should be avoided to prevent chemical changes in certain components of the soil. After drying, remove the aluminum box and place it in a desiccator to cool to room temperature. Then weigh the sample using an electronic balance and record the total mass (m2) of the aluminum box and the dried soil sample. Calculate the sample moisture content using the following formula: ; (3) Soil pore water salinity measurement Accurately weigh 5-10g of the prepared soil sample and place it in a clean conical flask or plastic bottle. Mix the soil sample with deionized water. Add the solution to deionized water in the specified proportion, tighten the cap, and shake on a shaker for 30 minutes to ensure that the salts in the soil are fully dissolved in the deionized water. The shaking speed should be moderate to avoid splashing. After shaking, let the extract stand for 30 minutes to allow soil particles to settle. After the turbid and clear layers separate, take the upper clear layer and measure its salinity using a YSI salinity meter. Combined with the corresponding mass moisture content measured in the previous step, the soil pore water salinity value is converted. ; The formula for converting pore water salinity is: .

[0023] (4) Evaluation indicators In statistics, the coefficient of variation is an important indicator of data dispersion. Therefore, the vertical hydrological connectivity of wetlands can be constructed by combining the coefficient of variation with the salinity of pore water in each soil layer. The calculation formula is as follows: ; in The connectivity index is N, where N is the number of measurement points on the soil profile. For salinity values ​​at a single measurement point, This represents the average salinity at the measurement points along the soil profile.

[0024] This method incorporates soil salinity indices and statistical methods, including the coefficient of variation, to provide a practical and quantifiable evaluation index for wetland vertical hydrological connectivity. The method is simple to operate, highly feasible, and provides rapid results, offering a basis for coastal wetland ecological protection planning. This wetland vertical hydrological connectivity assessment considers the fluctuations in salt transport in the topsoil under different landforms. Greater salinity fluctuations and differences indicate poorer overall connectivity, which is reflected in the index as follows: The closer it is to 1, the better the connectivity.

[0025] The following description, in conjunction with a preferred embodiment, illustrates the content involved in the above embodiments.

[0026] (1) Sampling and detection stage Habitat distribution around tidal ditch as follows Figure 2 As shown, considering that ideal sampling points should be distributed along the tidal channel, samples were collected at different elevations perpendicular to the tidal channel in the upstream, midstream and downstream directions. The samples should cover different ecological landform types such as bare soil areas, vegetation areas (Suaeda salsa / Tamarix chinensis), and saline areas. One soil sample was collected for each landform. Therefore, four sampling points were selected in this embodiment. Figure 2The diagram illustrates the salt distribution and change mechanism in different geomorphic zones of tidal channels (such as the bare beach area, Suaeda salsa area, Tamarix chinensis area, and salt return area), and explains the rationality and scientific validity of the soil salinity variation coefficient as an evaluation index of vertical hydrological connectivity from the perspective of geomorphology and ecosystem.

[0027] During the sampling process, the soil profile was sampled at a depth of 100cm, with samples taken every 10cm. The samples were sealed on-site and then processed in the laboratory, including drying, weighing, solution preparation, and distillation extraction. The soil moisture content and pore water salinity have been determined.

[0028] (2) Water and salt analysis Within a 1-meter range of the soil profile, the soil moisture content across different landforms was approximately 30%. This area experiences frequent tidal flooding, resulting in a shallow groundwater level and generally high moisture content in the shallow soil. Overall, soil moisture content did not show significant differences in depth, except in the higher-elevation saline-alkali areas where moisture content tended to increase with depth. Therefore, soil moisture content alone cannot directly reflect differences in vertical soil connectivity.

[0029] According to the measured results, the salinity of the surface soil pore water in the salinization zone showed significant vertical variation. Large-scale blockage of the transport pathways for salt to the lower soil layers slowed down salt transport, resulting in a clear gradient. The salinity of the soil pore water in the *Tamarix chinensis* area was generally slightly lower than in the salinization zone. The growth of *Tamarix chinensis* significantly increases soil permeability, and the lower elevation results in shallower groundwater depth. The root system's absorption of seawater and its role in promoting rainfall infiltration enhance vertical exchange, to some extent offsetting the salinization effect caused by evaporation. The hemispherical morphology of *Suaeda salsa* effectively shields the surrounding soil, and plant transpiration replaces direct soil evaporation, slowing the accumulation of salt to the soil surface. The soil salinity level in the *Suaeda salsa* area was low with even smaller vertical differences, generally maintained between 25-50 ppt. In the Guangtan area, the soil salinity remained consistently around 25 ppt from top to bottom, close to seawater levels. Frequent seawater inundation and a strong tidal pump effect promoted vertical hydrological connectivity and material exchange.

[0030] (4) Evaluation indicators In statistics, the coefficient of variation is an important indicator of data dispersion. Therefore, the vertical hydrological connectivity of wetlands can be constructed by combining the coefficient of variation with the salinity of pore water in each soil layer. The calculation formula is as follows: ; in The connectivity index is N, where N is the number of measurement points on the soil profile. For salinity values ​​at a single measurement point, This represents the average salinity at the measurement points along the soil profile. The closer it is to 1, the better the connectivity.

[0031] The bare beach area in the nearshore region is in a long-term tidal fluctuation zone with obvious seawater infiltration. The connectivity index is about 0.9, which is relatively high. Vegetation growth provides a good channel for the vertical transport of salt, and the salt distribution is more uniform. The connectivity index is 0.7 to 0.9, which shows good connectivity. The salt return area, which is far away from the tidal channel and located at a high position, has a connectivity index of about 0.5, which is poor overall.

[0032] In actual operation, this invention can be reasonably adjusted according to the conditions of the study area, including the selection of geomorphological sampling points and the depth of soil sampling.

[0033] Example 2: This example provides a rapid assessment device for vertical hydrological connectivity in coastal wetlands, comprising: The acquisition module is used to acquire the soil moisture content and soil pore water salinity obtained by pre-sampling and layering of the soil. The evaluation module is used to calculate the vertical hydrological connectivity index of each sampling point based on soil moisture content and soil pore water salinity, and to achieve rapid evaluation of vertical hydrological connectivity through the connectivity index.

[0034] The specific functions of each module described above are explained in the relevant content of the method in Embodiment 1, and will not be repeated here.

[0035] Example 3: This example provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the methods described in Example 1.

[0036] Example 4: This example provides a computer device, including: Memory, used to store computer programs / instructions; A processor for executing the computer program / instructions to implement the steps of any of the methods described in Embodiment 1.

[0037] Example 5: This example provides a computer program product, including a computer program / instructions, which, when executed by a processor, implement the steps of the method described in any one of Examples 1.

[0038] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

[0039] Those skilled in the art will understand that embodiments of this disclosure can be provided as methods, systems, or computer program products. Therefore, this disclosure can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this disclosure can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0040] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0041] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0042] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure and not to limit its protection scope. Although this disclosure has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading this disclosure, they can still make various changes, modifications or equivalent substitutions to the specific implementation of the invention, but these changes, modifications or equivalent substitutions are all within the protection scope of the pending claims.

Claims

1. A rapid evaluation method for vertical hydrological connectivity of coastal wetlands, characterized in that, include: Obtain soil moisture content and soil pore water salinity by pre-sampling soil layers; Based on soil moisture content and soil pore water salinity, the vertical hydrological connectivity index of each sampling point is calculated using the following formula: ； in For connectivity metrics, The number of measurement points on the soil profile. The mean salinity values ​​at the soil profile measurement points. Salinity value at a single measurement point; The connectivity index enables rapid evaluation of vertical hydrological connectivity.

2. The rapid evaluation method for vertical hydrological connectivity of coastal wetlands according to claim 1, characterized in that, When performing stratified soil sampling, sampling points are selected on different wetland landforms. These sampling points are distributed at different elevation ranges. Shallow soil is drilled at the sampling points, and then stratified sampling is performed. The samples are then sealed on-site to obtain soil samples.

3. The rapid evaluation method for vertical hydrological connectivity of coastal wetlands according to claim 1, characterized in that, The method for measuring soil moisture content includes: The moisture content of the soil sample is calculated based on the pre-obtained mass of the container, the total mass of the container and the soil sample, and the total mass of the container and the dried soil sample. The calculation formula is as follows: ； in, The moisture content of the soil sample. For the mass of the container, The total mass of the container and soil sample. This refers to the total mass of the container and the dried soil sample.

4. The rapid evaluation method for vertical hydrological connectivity of coastal wetlands according to claim 3, characterized in that, The method for measuring soil pore water salinity includes: Soil pore water salinity was calculated using a saturated extraction method by measuring the salinity and corresponding moisture content of the supernatant. The calculation formula is as follows: ； in, For salinity values ​​at a single measurement point, The ratio of deionized water to soil sample. This refers to the salinity of the supernatant.

5. A rapid evaluation device for vertical hydrological connectivity of coastal wetlands, used to implement the rapid evaluation method for vertical hydrological connectivity of coastal wetlands as described in any one of claims 1-4, characterized in that, include: The acquisition module is used to acquire the soil moisture content and soil pore water salinity obtained by pre-sampling and layering of the soil. The evaluation module is used to calculate the vertical hydrological connectivity index of each sampling point based on soil moisture content and soil pore water salinity, and to achieve rapid evaluation of vertical hydrological connectivity through the connectivity index.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: When executed by a processor, the program implements the steps of the method described in any one of claims 1-4.

7. A computer device, characterized in that, include: Memory, used to store computer programs / instructions; A processor for executing the computer program / instructions to implement the steps of the method according to any one of claims 1-4.

8. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instructions are executed by the processor, they implement the steps of the method described in any one of claims 1-4.

Images