Coral reef ecosystem community carbon sequestration evaluation method based on Lagrange drift trajectory

Abstract

The invention discloses a coral reef ecosystem community carbon sequestration evaluation method based on a Lagrange drift trajectory, and belongs to the field of marine ecological environment monitoring and carbon cycle research. The device comprises a drift tracking module, a CTD module, a hydrochemical parameter acquisition module, a depth instrument, a waterproof system and a buoyancy system, all the modules are integrated in the waterproof system, the buoyancy system is connected with the exterior of the waterproof system, and the modules are in signal connection to realize data transmission; according to the method, a Lagrange drift path and a time interval are recorded through the drift tracking module, the CTD module collects the temperature and salinity of a water body, the hydrochemical parameter collection module obtains total alkalinity and dissolved inorganic carbon and calculates the variable quantity of the total alkalinity and the dissolved inorganic carbon, and the depth instrument monitors the average water depth; the COexchange flux is calculated in combination with meteorological data, and then the net calcification rate and the net photosynthesis rate are obtained through a preset formula.

Description

Technical Field

[0001] This invention belongs to the field of marine ecological environment monitoring and carbon cycle research, specifically involving the application of drifting devices based on the Lagrange method, and further belonging to the technical field of calculating the calcification and carbon sequestration rate of coral reef ecosystem communities. Background Technology

[0002] Coral reef ecosystems are a crucial component of the marine carbon cycle. Their calcification and carbon sequestration processes not only determine the rate of reef biobuilding but also play a key role in global carbon balance. Currently, commonly used methods for measuring community calcification and carbon sequestration mainly include the still water tank method and the Eulerian fixed-point current method. While these methods meet basic measurement needs to some extent, they have significant limitations in practical applications. Specifically, the still water tank method and the Eulerian fixed-point current method have poor spatial representativeness, making it difficult to reflect the overall metabolic status of the coral reef ecosystem. Furthermore, significant flow interference during measurement can easily affect the accuracy of parameter acquisition. Additionally, they require considerable human intervention, have low automation levels, and increase operational complexity and the risk of human error.

[0003] The Lagrangian method, by tracking the actual movement path of water masses, can acquire time-varying chemical parameters under natural flow conditions, thereby enabling dynamic assessment of community-scale carbon metabolism. Compared to traditional methods, it is more closely aligned with the natural environmental characteristics of coral reef ecosystems. However, current technologies based on the Lagrangian method still have shortcomings. There is a lack of integrated, autonomously drifting dedicated devices, hindering the efficient coordination of path tracking and parameter acquisition. Furthermore, a systematic computational workflow has not been established, making it difficult to systematically transform the collected multi-dimensional data into accurate assessments of calcification and carbon sequestration rates. These limitations restrict the widespread application of this method in carbon sequestration assessments of coral reef ecosystems. Summary of the Invention

[0004] The purpose of this invention is to provide a method and apparatus for assessing carbon sequestration in coral reef ecosystem communities based on Lagrangian drift trajectories, in order to address the problems of poor spatial representativeness and high degree of human intervention in traditional carbon sequestration measurement methods, as well as the lack of integrated autonomous drift devices and systematic calculation processes in existing Lagrangian methods.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A method for assessing carbon sequestration in coral reef ecosystem communities based on Lagrange drift trajectories includes the following steps:

[0007] The Lagrange drift path of the water body is recorded using a drift tracking module;

[0008] The water body's hydrochemical parameters were collected and data quality control and time alignment were performed during the monitoring period corresponding to the Lagrange drift path.

[0009] Based on the aforementioned hydrochemical parameters and the seawater carbonate balance equation, the seawater carbonate balance parameters were calculated.

[0010] Combining meteorological data with the seawater carbonate balance parameters, the CO2 exchange flux at the air-seawater interface was calculated using the CO2 flux formula.

[0011] Based on the changes in the water chemical parameters, seawater density, average water depth, and CO2 exchange flux, the net calcification rate and net photosynthetic rate were calculated respectively.

[0012] In one possible implementation, the drift tracking module includes a GPS positioning unit, which is used to achieve real-time tracking and attitude correction of the Lagrange drift path.

[0013] In one possible implementation, the water chemical parameters include dissolved inorganic carbon, total alkalinity, and pH value, and the water temperature and salinity data are acquired simultaneously through a water chemical parameter acquisition module when collecting the water chemical parameters.

[0014] In one possible implementation, the seawater carbonate balance parameters include seawater CO2 partial pressure, CO2 solubility, carbonate saturation, and bicarbonate concentration. The seawater carbonate balance parameters are calculated by using any two of the water chemistry parameters as primary parameters and the other as quality control parameters, combined with the temperature and salinity data.

[0015] In one possible implementation, the meteorological data includes a preset altitude wind speed and atmospheric CO2 partial pressure. A gas exchange rate constant is calculated based on the preset altitude wind speed. The CO2 exchange flux is calculated by combining the gas exchange rate constant, the CO2 solubility, and the CO2 partial pressure difference between seawater and the atmosphere using the air-seawater interface CO2 flux formula.

[0016] In one possible implementation, when calculating the net calcification rate, the change in total alkalinity is multiplied by the seawater density and the average water depth, and then divided by twice the time interval. The error caused by the velocity gradient is corrected by the path integral method.

[0017] In one possible implementation, when calculating the net photosynthetic rate, the change in dissolved inorganic carbon is multiplied by the seawater density and the average water depth, and then divided by the time interval. The CO2 exchange flux is used to correct for the change in dissolved inorganic carbon caused by gas exchange.

[0018] In one possible implementation, during the data quality control, abnormal data is removed and missing data is supplemented, and time alignment is used to make the water chemical parameters correspond one-to-one with the time nodes of the Lagrange drift path.

[0019] In one possible implementation, the average water depth is obtained by monitoring with a depth gauge, and the average water depth of adjacent time periods within the monitoring period is taken as the average water depth.

[0020] In one possible implementation, the seawater density is calculated from the temperature and salinity data, or a preset seawater density constant is used.

[0021] Compared with the prior art, the beneficial effects of this invention are as follows: The integrated drift device of this invention includes a drift tracking module, a CTD module, a water chemical parameter acquisition module, and a waterproof buoyancy system. Each module works together to achieve real-time path recording, temperature and salinity monitoring, and automatic acquisition of water chemical parameters without much manual intervention. This not only improves the automation level of carbon sequestration assessment and reduces errors caused by manual operation, but also ensures the continuity and timeliness of parameter acquisition.

[0022] This invention tracks the actual movement path of water masses using the Lagrange method and obtains chemical parameters under natural flow conditions. Compared with the traditional still water tank method and the Eulerian fixed-point velocity method, it effectively avoids the influence of flow disturbance on the measurement. At the same time, it can reflect the overall community metabolism of the coral reef ecosystem, improve the spatial representativeness of carbon sequestration assessment, and is applicable to dynamic environments such as tidal and wave zones, thus enhancing the environmental adaptability of the method.

[0023] The calculation process of this invention solves key equilibrium parameters through the seawater carbonate equilibrium equation, corrects the influence of gas exchange on dissolved inorganic carbon by combining the CO2 flux formula at the air-seawater interface, and corrects the error caused by the velocity gradient by using the path integral method. These multiple steps ensure the accuracy of the calculation of net calcification rate and net photosynthetic rate, and improve the accuracy of carbon sequestration assessment.

[0024] The drifting device and calculation process of this invention have good scalability and can be used in conjunction with equipment such as unmanned underwater vehicles and buoy systems to further expand the application scenarios of the method. It can not only meet the carbon sequestration assessment needs of different coral reef areas, but also provide more diverse technical means for marine ecological environment monitoring and carbon cycle research. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the Lagrange drift device according to an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the drift trajectory of the Sanya Lagrange device according to an embodiment of the present invention;

[0028] Figure 3 This is a flowchart illustrating the method for assessing carbon sequestration in coral reef ecosystem communities according to an embodiment of the present invention. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0030] Example:

[0031] It should be noted that the terms "comprising" and "having" and any variations thereof in the embodiments of the present invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such processes, methods, products, or devices.

[0032] The carbon sequestration assessment method for coral reef ecosystem communities based on Lagrange drift trajectories in this invention is applicable to a carbon sequestration assessment device for coral reef ecosystem communities. The device includes a drift tracking module, a CTD module, a water chemical parameter acquisition module, a waterproof system, and a buoyancy system. The drift tracking module, CTD module, and water chemical parameter acquisition module are all integrated inside the waterproof system, and the buoyancy system is externally connected to the waterproof system. The drift tracking module, CTD module, and water chemical parameter acquisition module are interconnected by signal.

[0033] Furthermore, the drift tracking module includes a main unit, a GPS positioning unit, and a speed recording unit; both the GPS positioning unit and the speed recording unit are signal-connected to the main unit of the drift tracking module to collaboratively record the Lagrange drift path and speed of the water body; the GPS positioning unit is also signal-connected to the CTD module and the water chemical parameter acquisition module respectively, and the speed recording unit is also signal-connected to the water chemical parameter acquisition module.

[0034] Furthermore, the CTD module includes a main body, a temperature sensor, and a salinity sensor; both the temperature sensor and the salinity sensor are signal-connected to the main body of the CTD module for collecting temperature and salinity data of the water body; the main body of the CTD module is signal-connected to the water chemical parameter acquisition module for transmitting temperature and salinity data to the water chemical parameter acquisition module.

[0035] Furthermore, the water chemistry parameter acquisition module includes a water sample acquisition system and a parameter detection unit; the water sample acquisition system is located inside the waterproof system and includes a micro water pump and an automatic sampling pipeline. The micro water pump is connected to one end of the automatic sampling pipeline, and the other end of the automatic sampling pipeline extends to the outside of the waterproof system; the parameter detection unit is connected to the water sample acquisition system by signal, and the water sample acquisition system is also connected to the CTD module by signal.

[0036] Furthermore, the parameter detection unit includes a DIC sensor, a TA sensor, and a pH sensor; the DIC sensor, TA sensor, and pH sensor are all connected to the water sample acquisition system for detecting dissolved inorganic carbon, total alkalinity, and pH value in the water; the DIC sensor, TA sensor, and pH sensor are also connected to the main unit of the drift tracking module.

[0037] Furthermore, it also includes a depth gauge; the depth gauge is located inside the waterproof system and is connected to the parameter detection unit of the water chemical parameter acquisition module to transmit water depth data; the depth gauge is also connected to the main component of the CTD module.

[0038] Furthermore, the buoyancy system is a floating ball; the floating ball is fixedly connected to the top exterior of the waterproof system to provide buoyancy for the entire device, allowing the device to remain at a preset water level and drift with the water.

[0039] Furthermore, the water chemical parameter acquisition module also includes a control unit; the control unit is connected to the micro water pump of the water sample acquisition system to control the start and stop of the micro water pump and adjust the collection rhythm of water samples; the control unit is also connected to the speed recording unit of the drift tracking module to adjust the acquisition frequency according to the water movement speed.

[0040] Furthermore, the water chemical parameter acquisition module also includes a timing unit; the timing unit is signal-connected to the GPS positioning unit of the drift tracking module, and is used to correlate the GPS positioning information with the acquisition time information of the water chemical parameters; the timing unit is also signal-connected to the main component of the CTD module.

[0041] See Figure 3 The method includes:

[0042] Step 101: Use the drift tracking module to record the Lagrange drift path of the water body.

[0043] Step 102: Collect water chemical parameters of the water body and perform data quality control and time alignment during the monitoring period corresponding to the Lagrange drift path.

[0044] The water chemical parameters include dissolved inorganic carbon, total alkalinity, and pH value. When collecting the water chemical parameters, the temperature and salinity data of the water body are acquired simultaneously through the water chemical parameter acquisition module.

[0045] During the data quality control process, abnormal data is removed and missing data is supplemented. Time alignment is used to ensure that the water chemical parameters correspond one-to-one with the time nodes of the Lagrange drift path.

[0046] Step 103: Calculate the seawater carbonate balance parameters based on the aforementioned water chemistry parameters and the seawater carbonate balance equation.

[0047] The seawater carbonate balance parameters include seawater CO2 partial pressure, CO2 solubility, carbonate saturation, and bicarbonate concentration. The seawater carbonate balance parameters are calculated by using any two of the water chemistry parameters as the main parameters and the other as the quality control parameter, combined with the temperature and salinity data.

[0048] Step 104: Combining meteorological data with the seawater carbonate balance parameters, calculate the CO2 exchange flux using the air-seawater interface CO2 flux formula.

[0049] The meteorological data includes wind speed at a preset altitude and atmospheric CO2 partial pressure. The gas exchange rate constant is calculated based on the wind speed at the preset altitude. The CO2 exchange flux is calculated by combining the gas exchange rate constant, the CO2 solubility, and the CO2 partial pressure difference between seawater and the atmosphere using the CO2 flux formula at the air-seawater interface.

[0050] Specifically, the CO2 exchange flux FCO2 = k × K0 × ρ × ΔpCO2 × 1000;

[0051] In the formula, k is the gas exchange rate constant, K0 is the CO2 solubility, ρ is the seawater density, and ΔpCO2 is the CO2 partial pressure difference between seawater and the atmosphere.

[0052] Step 105: Calculate the net calcification rate and net photosynthetic rate based on the changes in the water chemical parameters, seawater density, average water depth, and CO2 exchange flux.

[0053] In calculating the net calcification rate, the change in total alkalinity is multiplied by the seawater density and the average water depth, and then divided by twice the time interval. The error caused by the velocity gradient is corrected by the path integral method.

[0054] Specifically, the net calcification rate Gnet = −ΔTA × ρ × h / (2 × Δt × 1000);

[0055] In the formula, ΔTA is the change in total alkalinity, ΔTA = TA_final − TA_initial, ρ is the seawater density, h is the average water depth, and Δt is the time interval.

[0056] In calculating the net photosynthetic rate, the change in dissolved inorganic carbon is multiplied by the seawater density and the average water depth, and then divided by the time interval. The CO2 exchange flux is used to correct for the change in dissolved inorganic carbon caused by gas exchange.

[0057] Specifically, the net photosynthetic rate Pnet = −ΔDIC×ρ×h / (Δt×1000)−FCO2;

[0058] In the formula, ΔDIC is the change in dissolved inorganic carbon, ΔDIC=DIC_final−DIC_initial, ρ is the seawater density, h is the average water depth, Δt is the time interval, and FCO2 is the CO2 exchange flux;

[0059] The average water depth is obtained by monitoring with a depth gauge, and the average water depth of adjacent time periods within the monitoring period is taken as the average water depth.

[0060] The seawater density is calculated from the temperature and salinity data, or by using a preset seawater density constant.

[0061] To further illustrate the practical application effect of the coral reef ecosystem community carbon sequestration assessment method and device based on Lagrange drift trajectory of the present invention, a field drift experiment was conducted in the Luhuitou reef area of ​​Sanya. The experimental process and data collection were completed using the Lagrange device of the present invention. The device structure can be referred to the attached diagram. Figure 1 Understanding, attached Figure 1 The buoyancy provided by the floating ball stabilizes the device in the target water layer. The GPS positioning unit and the speed recording unit work together to record the drift trajectory, and the water chemical parameter acquisition module is responsible for water sample collection and parameter detection.

[0062] The experiment lasted for one hour. Under the natural influence of local currents, the Lagrange device drifted along the surface of the reef. During the experiment, the device's built-in GPS positioning unit continuously recorded changes in latitude and longitude. Combined with the motion speed data collected by the speed recording unit, the drift path length of the device was calculated to be approximately 0.22 kilometers. This path length effectively covers the typical community area of ​​the reef, ensuring that the collected data is representative at the community scale.

[0063] The data recording and water sample collection for the experiment were both set to be performed every 10 minutes: each time a record was made, the drift tracking module simultaneously output real-time trajectory data, the water chemistry parameter acquisition module simultaneously recorded real-time water chemistry data, and the water sample collection system was started at the same time to collect on-site water samples through a micro water pump and an automatic sampling pipeline; the collected water samples will be used for subsequent analysis of three parameters: DIC, TA, and pH. The analysis results will be used to verify the accuracy of the real-time water chemistry data.

[0064] During the experiment, the device's CTD module continuously monitored the water temperature and salinity. The monitoring results showed that the temperature ranged from 29.3°C to 29.7°C, and the average salinity remained stable at 33.8. The depth gauge monitored the depth of the water layer in real time. The data showed that the water depth remained at approximately 3m during the experiment, ensuring that the device always collected data within the preset vertical water layer and avoiding the impact of water depth fluctuations on parameter consistency. At the same time, wind speed data of the experimental area were collected by an external meteorological station. The records showed that the wind speed during the experiment was approximately 3.5m / s. This data will be used to determine the gas exchange rate constant in the subsequent calculation of CO2 exchange flux at the air-seawater interface.

[0065] Throughout the experiment, the device's waterproof system effectively isolated seawater, ensuring the stable operation of internal components such as the drift tracking module, CTD module, water chemical parameter acquisition module, and depth gauge. The modules interact with each other in real time through signal connections. For example, the temperature and salinity data acquired by the CTD module are transmitted to the water chemical parameter acquisition module in real time, providing environmental background data for the detection of water chemical parameters and ensuring that all acquired data correspond to the same spatiotemporal conditions.

[0066] The drift trajectory of the Sanya Lagrange device is as follows: Figure 2 The latitude and longitude data (every 10 minutes) are shown in Table 1 below:

[0067] Water chemistry sampling data (every 10 minutes) are shown in Table 2 below:

[0068] Based on field observations and sampling data, the community net calcification rate (Gnet), net photosynthetic rate (Pnet), and CO2 exchange flux were calculated:

[0069] The main calculation formulas are as follows:

[0070] ①Net calcification rate:

[0071] Gnet=−ΔTA×ρ×h / (2×Δt×1000)

[0072] ②Net photosynthetic rate:

[0073] Pnet=−ΔDIC×ρ×h / (Δt×1000)−FCO2

[0074] ③CO2 exchange flux:

[0075] FCO2 = k × K0 × ρ × ΔpCO2 × 1000

[0076] in:

[0077] ΔTA = TA_final − TA_initial

[0078] ΔDIC = DIC_final - DIC_initial

[0079] ρ = 1025 kg·m⁻³ (seawater density), h = 3 m (average water depth), Δt = 1 h (drift time), K0 = 3.0 × 10⁻² mol·kg⁻¹·atm⁻¹ (CO₂ solubility), ΔpCO₂ = (pCO₂_sea − pCO₂_air) / 10 6 k = 3.99 cm·h⁻¹ = 0.0399 m·h⁻¹ (Gas exchange coefficient at a wind speed of 4 m / s)

[0080] The parameters are explained as follows: Gnet (Net Calcification Rate): Net rate of CaCO3 formation per unit area per unit time in the community; positive values ​​indicate net calcification, unit: mmol·m⁻²·h⁻¹. Pnet (Net Photosynthetic Rate): Net rate of organic carbon fixation per unit area per unit time in the community; positive values ​​indicate net autotrophy, unit: mmol·m⁻²·h⁻¹. FCO2 (Air-Seawater CO2 Flux): CO2 exchange flux at the air-sea interface; positive values ​​indicate release into the atmosphere, negative values ​​indicate absorption into the ocean, unit: mmol·m⁻²·h⁻¹. ΔTA: Change in total alkalinity, unit: μmol·kg⁻¹; TA decreases by approximately 2 mol for every 1 mol of CaCO3 formed by calcification. ΔDIC: Change in dissolved inorganic carbon, unit: μmol·kg⁻¹; photosynthesis reduces DIC. ρ: Seawater density, default 1025 kg·m⁻³, can be calculated precisely using T and S. h: Representative water depth of the sampled / observed water layer or average water depth over adjacent time periods (m). Δt: Time interval (h); in this example, 1 h. k: Gas exchange rate constant (m·h⁻¹), calculated using Wanninkhof (2014)'s formula for CO2 at a height of 10 m in seawater, based on wind speed u10. K0: Solubility of CO2 in seawater (mol·kg⁻¹·atm⁻¹), calculated using Weiss (1974)'s formula for CO2 solubility in seawater. ΔpCO2: Difference between seawater and atmospheric pCO2 (pCO2_sea−pCO2_air), expressed in atm; μatm needs to be divided by 10. 6Convert to ATM.

[0081] Substituting the data, we can obtain the following from the sampled data:

[0082] ΔTA=2254−2270=−16μmol·kg⁻¹

[0083] ΔDIC=2113−2140=−27μmol·kg⁻¹

[0084] Calculation steps:

[0085] ①Net calcification rate:

[0086] Gnet=−(−16)×1025×3 / (2×1×1000)=24.6 mmol·m⁻²·h⁻¹

[0087] ②Net photosynthetic rate (excluding air-sea flux correction):

[0088] Pnet=−(−27)×1025×3 / (1×1000)=83.0 mmol·m⁻²·h⁻¹

[0089] ③CO2 exchange flux:

[0090] FCO2=0.0399×3.0×10⁻²×1025×(−25×10⁻ 6 )×1000

[0091] ≈−0.031 mmol·m⁻²·h⁻¹ (The value is negligible)

[0092] Therefore: Pnet = Pnet*−FCO2≈83.0−(−0.031)≈83.03 mmol·m⁻²·h⁻¹

[0093] Summary of results:

[0094] Net calcification carbon fixation rate Gnet = 24.6 mmol·m⁻²·h⁻¹

[0095] Net photosynthetic carbon fixation rate Pnet = 83.0 mmol·m⁻²·h⁻¹

[0096] Note: The above results are the average rates of the 1-hour drift segment, representing the instantaneous intensity under high photosynthetic conditions during the day.

[0097] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0098] The above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made based on the essence of the content of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for assessing carbon sequestration in coral reef ecosystem communities based on Lagrange drift trajectories, characterized in that, Includes the following steps: The Lagrange drift path of the water body is recorded using a drift tracking module; The water body's hydrochemical parameters were collected and data quality control and time alignment were performed during the monitoring period corresponding to the Lagrange drift path. Based on the aforementioned hydrochemical parameters and the seawater carbonate balance equation, the seawater carbonate balance parameters were calculated. Combining meteorological data with the seawater carbonate balance parameters, the CO2 exchange flux at the air-seawater interface was calculated using the CO2 flux formula. Based on the changes in the water chemical parameters, seawater density, average water depth, and CO2 exchange flux, the net calcification rate and net photosynthetic rate were calculated respectively.

2. The method for assessing carbon sequestration in coral reef ecosystem communities based on Lagrange drift trajectories according to claim 1, characterized in that, The drift tracking module includes a GPS positioning unit, which is used to achieve real-time tracking and attitude correction of the Lagrange drift path.

3. The method for assessing carbon sequestration in coral reef ecosystem communities based on Lagrange drift trajectories according to claim 1, characterized in that, The water chemical parameters include dissolved inorganic carbon, total alkalinity, and pH value. When collecting the water chemical parameters, the temperature and salinity data of the water body are acquired simultaneously through the water chemical parameter acquisition module.

4. The method for assessing carbon sequestration in coral reef ecosystem communities based on Lagrange drift trajectories according to claim 1, characterized in that, The seawater carbonate balance parameters include seawater CO2 partial pressure, CO2 solubility, carbonate saturation, and bicarbonate concentration. The seawater carbonate balance parameters are calculated by using any two of the water chemistry parameters as the primary parameters and the other as the quality control parameter, combined with the temperature and salinity data.

5. The method for assessing carbon sequestration in coral reef ecosystem communities based on Lagrange drift trajectories according to claim 1, characterized in that, The meteorological data includes wind speed at a preset altitude and atmospheric CO2 partial pressure. The gas exchange rate constant is calculated based on the wind speed at the preset altitude. The CO2 exchange flux is calculated by combining the gas exchange rate constant, the CO2 solubility, and the CO2 partial pressure difference between seawater and the atmosphere using the CO2 flux formula at the air-seawater interface.

6. The method for assessing carbon sequestration in coral reef ecosystem communities based on Lagrange drift trajectories according to claim 1, characterized in that, When calculating the net calcification rate, the change in total alkalinity is multiplied by the seawater density and the average water depth, and then divided by twice the time interval. The error caused by the velocity gradient is corrected by the path integral method.

7. The method for assessing carbon sequestration in coral reef ecosystem communities based on Lagrange drift trajectories according to claim 1, characterized in that, When calculating the net photosynthetic rate, the change in dissolved inorganic carbon is multiplied by the seawater density and the average water depth, and then divided by the time interval. The CO2 exchange flux is used to correct for the change in dissolved inorganic carbon caused by gas exchange.

8. The method for assessing carbon sequestration in coral reef ecosystem communities based on Lagrange drift trajectories according to claim 1, characterized in that, During the data quality control process, abnormal data is removed and missing data is supplemented. Time alignment is used to ensure that the water chemical parameters correspond one-to-one with the time nodes of the Lagrange drift path.

9. The method for assessing carbon sequestration in coral reef ecosystem communities based on Lagrange drift trajectories according to claim 1, characterized in that, The average water depth is obtained by monitoring with a depth gauge, and the average water depth of adjacent time periods within the monitoring period is taken as the average water depth.

10. The method for assessing carbon sequestration in coral reef ecosystem communities based on Lagrange drift trajectories according to claim 1, characterized in that, The seawater density is calculated from the temperature and salinity data, or by using a preset seawater density constant.

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