Methods based on hydrogen and oxygen isotope quantification of upwelling intensity and its biogeochemical processes

Abstract

This invention discloses a method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes. The method includes: acquiring hydrological information and hydrogen and oxygen isotope values ​​of a target sea area, and establishing a hydrogen and oxygen isotope mass balance model; calculating the proportion of different source water bodies in the upwelling influence zone of the target sea area based on the hydrogen and oxygen isotope mass balance model, and obtaining the contribution of deep water to the upwelling influence zone; estimating the theoretical nutrient concentration of the upwelling influence zone based on the nutrient concentrations of the original surface water and the deep water at the upwelling source, as well as the contribution of deep water to the upwelling influence zone; and comparing the measured nutrient concentration of the upwelling influence zone with the theoretical nutrient concentration to obtain the contribution of biological processes in the target sea area. This invention leverages the advantage that water hydrogen and oxygen isotopes are tracers of water itself, developing a method for quantifying upwelling intensity and its biogeochemical processes, providing a new technical approach for the scientific quantitative assessment of upwelling ecosystems.

Description

Technical Field

[0001] This invention relates to the field of coupling and simulation technology of upwelling and marine biogeochemical processes, and in particular to a method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes. Background Technology

[0002] Upwelling refers to the upward movement of water and is an important component of ocean circulation. Upwelling brings abundant nutrients to the upper water layers, significantly promoting primary marine productivity. Areas with strong upwelling are characterized by low temperatures, high salinity, high nutrient levels, and high primary productivity, often forming excellent fishing grounds (such as the famous Peruvian fishing grounds). The East my country Sea and South China Sea have numerous coastal upwelling areas. Quantitative analysis of upwelling intensity and its impact on marine biogeochemistry is of great significance for fisheries and the marine ecological environment.

[0003] However, the limitations of traditional methods restrict scholars' specific understanding of the quantitative characteristics and intensity of upwelling. Traditionally, temperature and salinity have long been used to indicate upwelling conditions, and this method remains widely used. However, this method has limitations because temperature and salinity are not conservative and are not tracers of the water itself, especially in offshore oceans where the salinity differences between surface, subsurface, and deep water layers are relatively small, making it impossible to indicate the presence of upwelling. Hydrogen and oxygen isotopes (δD and δ¹⁸O) from water from different sources... 18 The composition of oxygen varies considerably, for example, the δD and δ¹⁸O of nearshore terrestrial input freshwater and the surface water of the open ocean affected by rainfall. 18 O values ​​are often low. Therefore, δD and δ 18 O can be used to trace the upflow, and δD and δ 18 Combining oxygen with temperature and salinity can overcome the shortcomings of traditional methods. The δD and δδ of water... 18 O's advantage lies in its conservatism; it acts as a tracer for water itself, showing the δD and δδ of water at different depths within the upwelling influence zone. 18 O values ​​often vary more significantly because runoff, precipitation, evaporation, and upwelling of high-salinity deep water all affect the isotopic composition of water. Therefore, whether in coastal areas or in the open ocean, there are significant differences in the isotopes of surface, subsurface, and deep water. Based on these characteristics, the intensity of global ocean upwelling can be well quantified.

[0004] In summary, traditional temperature-salinity methods still have limitations in tracing upwellings, making it difficult to quantify upwelling intensity and its biogeochemical processes. Therefore, there is an urgent need for a water-based hydrogen and oxygen isotope technique to quantify upwelling intensity and its biogeochemical processes to address this problem. Summary of the Invention

[0005] To address the technical problems existing in the prior art, this invention proposes a method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes. By using a hydrogen and oxygen isotope mass balance model to quantify upwelling intensity based on the differences in hydrogen and oxygen isotopes in water at different depths and in different regions, this invention provides a new technical method for quantitatively analyzing the impact of upwelling on marine biogeochemical processes.

[0006] To achieve the above objectives, this invention provides a method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes, comprising:

[0007] Obtain hydrological information and hydrogen and oxygen isotope values ​​for the target sea area, and establish a hydrogen and oxygen isotope mass balance model.

[0008] Based on the hydrogen and oxygen isotope mass balance model, the proportion of different water bodies from different sources in the upwelling influence zone of the target sea area is calculated to obtain the contribution of deep water to the upwelling influence zone.

[0009] Based on the nutrient concentrations of the original surface water and the deep water in the upwelling source area, as well as the contribution of the deep water to the upwelling influence zone, the theoretical nutrient concentration of the upwelling influence zone is estimated.

[0010] The measured nutrient concentrations in the upwelling-affected area are compared with the theoretical nutrient concentrations to obtain the contribution of biological processes in the target sea area.

[0011] Preferably, establishing the hydrogen and oxygen isotope mass balance model includes:

[0012] Obtain the hydrological information and hydrogen and oxygen isotope values;

[0013] The upwelling influence zone was identified and distinguished by the relationship between hydrogen and oxygen isotopes in temperature, salinity, and water, and the distinction results were obtained.

[0014] The differentiation results are identified to form different water masses in the upwelling mixed water body, and the hydrogen and oxygen isotope values ​​of different end-member waters are determined based on the hydrological information and hydrogen and oxygen isotope values.

[0015] Based on the different water masses in the upwelling mixture and the hydrogen and oxygen isotope values ​​in the upwelling influence zone, the isotope mass balance model is established.

[0016] Preferably, obtaining hydrological information about the target sea area includes:

[0017] The hydrological information was obtained using CTD detection, and the survey period was during the season when the upwelling effect was significant.

[0018] Preferably, obtaining the hydrogen and oxygen isotope values ​​of the target sea area includes:

[0019] Seawater samples from different layers were collected in the target sea area using a Niskin water sampler. The samples were exposed to air for the same amount of time during collection. The samples were then filled with glass bottles and sealed. Subsequently, the hydrogen and oxygen isotope values ​​of the seawater were measured using a gas stable isotope ratio mass spectrometer within a fixed time period.

[0020] Preferably, identifying and distinguishing the upwelling influence zone based on the relationship between temperature, salinity, and hydrogen and oxygen isotopes in water includes:

[0021] Based on the planar and cross-sectional distribution maps of temperature, salinity, and hydrogen and oxygen isotopes in the target sea area, determine the surface water in the upwelling influence zone, the surface water in the non-upwelling influence zone, and the deep water in the upwelling influence zone.

[0022] The surface water in the upwelling influence zone is formed by the mixture of surface water in the non-upwelling influence zone and deep water in the upwelling influence zone.

[0023] Preferably, the isotopic mass balance model is as follows:

[0024] X h =f b ×X b +f s ×X s ;

[0025] f b +f s =1;

[0026] In the formula, X h X represents the average hydrogen or oxygen isotope concentration of surface water in the upwelling influence zone; b X represents the average hydrogen or oxygen isotope value of surface water in the non-upwelling influence zone; s f represents the average hydrogen or oxygen isotope concentration in the deep water within the upwelling influence zone. b The proportion of surface water in the non-upwelling influence zone; f s This represents the proportion of deep water in the upwelling influence zone.

[0027] Preferably, based on the law of nutrient mass balance during physical mixing, the theoretical nutrient concentration in the upwelling influence zone is quantitatively estimated, specifically as follows:

[0028] Y h =f b ×Y b +f s ×Y s ;

[0029] In the formula, Y h Y represents the theoretical estimate of nutrient concentration in the surface water of the upwelling influence zone. b Y represents the average surface nutrient concentration in the non-upwelling influence zone.s f represents the average nutrient concentration in the deep water within the upwelling influence zone. b The proportion of surface water in the non-upwelling influence zone; f s This represents the proportion of deep water in the upwelling influence zone.

[0030] Preferably, comparing the measured nutrient concentration in the upwelling influence zone with the theoretically estimated nutrient concentration in the surface water of the upwelling influence zone includes:

[0031] The average value of the measured nutrient concentration in the upwelling-affected area is denoted as Z. h ;

[0032] If (Y) h -Z h ) / Y h If the value is less than or equal to the preset threshold, it is considered that physical processes dominate the upwelling influence zone, and the influence of biological processes can be ignored.

[0033] If (Y) h -Z h ) / Y h If the value is greater than or equal to the preset threshold, then the biological processes in the upwelling influence zone are considered to be affected.

[0034] Compared with the prior art, the present invention has the following advantages and technical effects:

[0035] Based on the advantage that water hydrogen and oxygen isotopes are tracers of water itself, this invention develops a method for quantifying upwelling intensity and its biogeochemical processes, providing a new technical method for the scientific quantitative assessment of upwelling ecosystems. By establishing an isotope mass balance model, the proportion of water bodies from different sources in the upwelling influence zone can be accurately calculated, clarifying the specific contribution of deep water to the upwelling influence zone. Attached Figure Description

[0036] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0037] Figure 1 This is a flowchart of a method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes, according to an embodiment of the present invention. Detailed Implementation

[0038] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0039] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0040] This invention proposes a method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes, such as... Figure 1 ,include:

[0041] Obtain hydrological information and hydrogen and oxygen isotope values ​​for the target sea area, and establish a hydrogen and oxygen isotope mass balance model.

[0042] Based on the hydrogen and oxygen isotope mass balance model, the proportion of different water bodies from different sources in the upwelling influence zone of the target sea area is calculated to obtain the contribution of deep water to the upwelling influence zone.

[0043] Based on the nutrient concentrations of the original surface water and the deep water in the upwelling source area, as well as the contribution of deep water to the upwelling influence zone, the theoretical nutrient concentration of the upwelling influence zone is estimated.

[0044] By comparing the measured nutrient concentrations in the upwelling-affected area with the theoretical nutrient concentrations, the contribution of biological processes in the target sea area can be obtained.

[0045] Furthermore, establishing a hydrogen-oxygen isotope mass balance model includes:

[0046] Obtain hydrological information and hydrogen and oxygen isotope values ​​for the target sea area;

[0047] The upwelling influence zone was identified and distinguished by the relationship between hydrogen and oxygen isotopes in temperature, salinity, and water, and the distinction results were obtained.

[0048] The results of the differentiation are identified to form different water masses in the upwelling mixed water body, and the hydrogen and oxygen isotope values ​​of different end-member waters are determined based on hydrological information and hydrogen and oxygen isotope values.

[0049] Based on the different water masses in the upwelling mixture and the hydrogen and oxygen isotope values ​​in the upwelling influence zone, the isotope mass balance model is established.

[0050] Specifically, obtaining hydrological information about the target sea area includes:

[0051] The hydrological information was obtained using CTD detection during the on-site investigation. In this embodiment, the investigation was conducted during a season when the upwelling effect was significant.

[0052] Obtaining the hydrogen and oxygen isotope values ​​of the target sea area includes:

[0053] Seawater samples from different layers were obtained in the target sea area using a Niskin water sampler. The samples were exposed to air for the same duration during the sampling process (in this embodiment, the exposure to air did not exceed 1 minute). The samples were then filled with glass bottles and sealed. Subsequently, the hydrogen and oxygen isotope values ​​of the seawater were measured using a gas stable isotope ratio mass spectrometer within a fixed period of time (within one month).

[0054] Furthermore, the identification and differentiation of the upwelling influence zone through the relationship between temperature, salinity, and hydrogen and oxygen isotopes in water includes:

[0055] Based on the planar and cross-sectional distribution maps of temperature, salinity, and hydrogen and oxygen isotopes in the target sea area, determine the surface water in the upwelling influence zone, the surface water in the non-upwelling influence zone, and the deep water in the upwelling influence zone.

[0056] The surface water in the upwelling influence zone is formed by the mixture of surface water in the non-upwelling influence zone and deep water in the upwelling influence zone.

[0057] Specifically, the isotopic mass balance model is as follows:

[0058] X h =f b ×X b +f s ×X s ;

[0059] f b +f s =1;

[0060] In the formula, X h X represents the average hydrogen or oxygen isotope concentration of surface water in the upwelling influence zone; b X represents the average hydrogen or oxygen isotope value of surface water in the non-upwelling influence zone; s f represents the average hydrogen or oxygen isotope concentration in the deep water within the upwelling influence zone. b The proportion of surface water in the non-upwelling influence zone; f s This represents the proportion of deep water in the upwelling influence zone.

[0061] Furthermore, based on the principle of nutrient mass balance during physical mixing, and utilizing the nutrient concentrations of surface water in the non-upwelling influence zone and deep water in the upwelling influence zone, as well as their contributions to the upwelling influence zone, the theoretical nutrient concentration of surface water in the upwelling influence zone is quantitatively estimated, specifically:

[0062] Y h =f b ×Y b +f s ×Y s ;

[0063] In the formula, Y hY represents the theoretical estimate of nutrient concentration in the surface water of the upwelling influence zone. b Y represents the average surface nutrient concentration in the non-upwelling influence zone. s f represents the average nutrient concentration in the deep water within the upwelling influence zone. b The proportion of surface water in the non-upwelling influence zone; f s This represents the proportion of deep water in the upwelling influence zone.

[0064] Furthermore, the measured nutrient concentrations in the upwelling-affected area are compared with the theoretical estimates of nutrient concentrations in the surface water of the upwelling-affected area. If the difference is small, it indicates that physical processes are dominant; if the theoretical value is significantly lower than the measured value, it indicates that the upwelling promotes phytoplankton primary production. The contribution of biological processes can be quantitatively estimated based on the difference between the theoretical and measured values.

[0065] Specifically, the average value of the measured nutrient concentration in the upwelling-affected area is denoted as Z. h ;

[0066] If (Y) h -Z h ) / Y h If the percentage is ≤10%, then physical processes are considered to dominate the upwelling influence zone, and the influence of biological processes can be ignored; if (Y h -Z h ) / Y h If the percentage is ≥10%, then the biological processes in the upwelling influence zone are considered to have a certain impact.

[0067] Using the method of this embodiment, upwelling at different stages can be investigated and quantitatively analyzed separately to obtain the contribution of deep water to upwelling and the biological response at different stages.

[0068] This invention establishes an isotope mass balance model, which can accurately calculate the proportion of different water sources in the upwelling influence zone and clarify the specific contribution of deep water to the upwelling influence zone.

[0069] This invention enables quantitative analysis of upwelling intensity and its impact on marine biogeochemical processes, thus providing a scientific basis for the assessment and management of fishery resources. By understanding the changes in nutrients and the responses of biological processes brought about by upwelling, the distribution and trends of fishery resources can be predicted more accurately, leading to the formulation of rational fishing strategies and the sustainable utilization of fishery resources.

[0070] This invention combines hydrogen and oxygen isotope technology with oceanographic research, providing new ideas and methods for marine science research. This interdisciplinary innovative approach enables a more comprehensive and in-depth study of complex processes such as ocean circulation and material transport, expanding the depth and breadth of oceanographic research and providing new perspectives and tools for solving other problems in the field of marine science.

[0071] To more clearly illustrate the technical solution of the present invention, specific embodiments are provided below for description:

[0072] Example 1

[0073] Spring upwelling in western Guangdong:

[0074] Step 1: In May 2018 (spring), 33 stations across five transects were deployed in the nearshore waters of western Guangdong, covering the areas of 20.0-21.5°N, 110.0°E, and 112.0°E. These stations covered both nearshore and offshore areas of western Guangdong. CTDs were deployed on-site to acquire hydrological data such as temperature and salinity. Seawater samples were collected using water samplers to analyze the hydrogen and oxygen isotopes of the water. The upwelling influence zone was identified based on the water distribution characteristics of parameters such as temperature and salinity.

[0075] Step 2: Identify surface water in the upwelling influence zone, surface water in the non-upwelling influence zone, and deep water in the upwelling influence zone based on the horizontal distribution map, cross-sectional distribution map, temperature-salinity relationship map, etc. of temperature, salinity, and water.

[0076] Step 3: The surface water in the upwelling influence zone is formed by the mixture of surface water from the non-upwelling influence zone and deep water from the upwelling influence zone, based on the average oxygen isotope values ​​of different water bodies (surface water from the non-upwelling influence zone: δ...). 18 O = 0.2‰; Deep water in the upwelling influence zone: δ 18 O = 0.7‰; Surface water in the upwelling influence zone: δ 18 O=0.7‰), establish a mass balance model based on oxygen isotopes;

[0077] Step 4: Using the isotope mass balance model, the proportion of different water sources in the upwelling influence area is calculated. It is calculated that in spring, the surface water in the upwelling influence area of ​​western Guangdong is contributed by 40% by deep water and 60% by surface water from non-upwelling areas.

[0078] Step 5: Based on the nutrient concentration (NO3) of the surface water in the non-upwelling influence zone. - NH4 + PO4 3- and SiO3 2- The concentrations were 0.19 μmol / L, 0.59 μmol / L, 0.20 μmol / L and 5.55 μmol / L, respectively, and the nutrient concentrations (NO3) in the deep water of the upwelling influence zone were also observed. - NH4 + PO4 3- and SiO3 2-The concentrations of NO3- were 0.36 μmol / L, 0.56 μmol / L, 0.22 μmol / L, and 4.05 μmol / L, respectively, and their proportions in the surface water of the upwelling influence zone were used to estimate the theoretical concentrations of each nutrient (NO3-) in the upwelling influence zone. - NH4 + PO4 3- and SiO3 2- The concentrations were 0.36 μmol / L, 0.56 μmol / L, 0.22 μmol / L and 4.05 μmol / L, respectively.

[0079] Step 6: Measured NO3 levels in surface water within the upwelling influence zone - NH4 + PO4 3- and SiO3 2- The average concentrations were 0.08 μmol / L, 0.41 μmol / L, 0.21 μmol / L, and 2.81 μmol / L, respectively. Comparing the theoretical and measured values, it was found that NO3... - NH4 + PO4 3- and SiO3 2- The measured values ​​were 69%, 29%, -1%, and 43% lower than the theoretical values, respectively, indicating that organisms in this upwelling zone absorb nitrogen and silicon significantly in spring.

[0080] Example 2

[0081] Summer upwelling along the western coast of Guangdong:

[0082] Step 1: In August 2018 (summer), 33 stations across five transects were deployed in the nearshore waters of western Guangdong, covering the areas of 20.0-21.5°N, 110.0°E, and 112.0°E. These stations covered both nearshore and offshore areas of western Guangdong. CTDs were deployed on-site to acquire hydrological data such as temperature and salinity. Seawater samples were collected using water samplers to analyze the hydrogen and oxygen isotopes of the water. The upwelling influence zone was identified based on the water distribution characteristics of parameters such as temperature and salinity.

[0083] Step 2: Identify surface water in the upwelling influence zone, surface water in the non-upwelling influence zone, and deep water in the upwelling influence zone based on the horizontal distribution map, cross-sectional distribution map, temperature-salinity relationship map, etc. of temperature, salinity, and water.

[0084] Step 3: The surface water in the upwelling influence zone is formed by the mixture of surface water from the non-upwelling influence zone and deep water from the upwelling influence zone, based on the average oxygen isotope values ​​of different water bodies (surface water from the non-upwelling influence zone: δ...). 18 O = -1.9‰; Deep water in the upwelling influence zone: δ 18 O = -0.3‰; Surface water in the upwelling influence zone: δ18 O=-0.8‰), establish a mass balance model based on oxygen isotopes;

[0085] Step 4: Using the isotope mass balance model, the proportion of different water sources in the upwelling influence area is calculated. It is calculated that in summer, the surface water in the upwelling influence area of ​​western Guangdong is contributed by 69% of the deep water and 31% of the surface water in the non-upwelling area.

[0086] Step 5: Based on the surface water (NO3) in the non-upwelling influence zone - NH4 + PO4 3- and SiO3 2- The concentrations were 12.15 μmol / L, 2.35 μmol / L, 0.70 μmol / L, and 13.57 μmol / L, respectively, and the nutrient concentrations (NO3) in the deep water of the upwelling-affected zone were also observed. - NH4 + PO4 3- and SiO3 2- The concentrations of NO3- were 1.91 μmol / L, 0.55 μmol / L, 0.26 μmol / L, and 3.62 μmol / L, respectively, and their proportions of contribution to the upwelling influence zone were used to estimate the theoretical concentrations of each nutrient in the surface water of the upwelling influence zone (NO3). - NH4 + PO4 3- and SiO3 2- The concentrations were 6.01 μmol / L, 1.27 μmol / L, 0.44 μmol / L and 7.60 μmol / L, respectively.

[0087] Step 6: Measured NO3 levels in surface water within the upwelling influence zone - NH4 + PO4 3- and SiO3 2- The average concentrations were 0.32 μmol / L, 0.53 μmol / L, 0.14 μmol / L, and 1.37 μmol / L, respectively. Comparing the theoretical and measured values, it was found that NO3... - NH4 + PO4 3- and SiO3 2- The measured values ​​were 95%, 58%, 68%, and 82% lower than the theoretical values, respectively, indicating that organisms in the upwelling zone in summer significantly absorb various nutrients, and the biological processes are significantly affected.

[0088] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes, characterized in that, include: Obtain hydrological information and hydrogen and oxygen isotope values ​​for the target sea area, and establish a hydrogen and oxygen isotope mass balance model. Based on the hydrogen and oxygen isotope mass balance model, the proportion of different water bodies from different sources in the upwelling influence zone of the target sea area is calculated to obtain the contribution of deep water to the upwelling influence zone. Based on the nutrient concentrations of the original surface water and the deep water in the upwelling source area, as well as the contribution of the deep water to the upwelling influence zone, the theoretical nutrient concentration of the upwelling influence zone is estimated. The measured nutrient concentrations in the upwelling-affected area are compared with the theoretical nutrient concentrations to obtain the contribution of biological processes in the target sea area. Specifically, based on the principle of nutrient mass balance during physical mixing, the theoretical nutrient concentration in the upwelling-affected zone is quantitatively estimated, as follows: Y h = f b × Y b + f s × Y s ； In the formula, Y h This represents a theoretical estimate of the nutrient concentration in the surface water of the upwelling-affected zone. Y b This represents the average surface nutrient concentration in the non-upwelling influence zone. Y s This represents the average nutrient concentration in the deep water within the upwelling influence zone. f b The proportion of surface water in the non-upwelling influence zone; f s The proportion of deep water in the upwelling influence zone; The comparison between the measured nutrient concentrations in the upwelling-affected area and the theoretical estimates of nutrient concentrations in the surface water of the upwelling-affected area includes: The average value of the measured nutrient concentration in the upwelling-affected area is denoted as... Z h ; like( Y h - Z h ) / Y h If the value is less than or equal to the preset threshold, it is considered that physical processes dominate the upwelling influence zone, and the influence of biological processes can be ignored. like( Y h - Z h ) / Y h If the value is greater than or equal to the preset threshold, then the biological processes in the upwelling influence zone are considered to be affected.

2. The method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes according to claim 1, characterized in that, Establishing the hydrogen and oxygen isotope mass balance model includes: Obtain the hydrological information and hydrogen and oxygen isotope values; The upwelling influence zone was identified and distinguished by the relationship between hydrogen and oxygen isotopes in temperature, salinity, and water, and the distinction results were obtained. The differentiation results are identified to form different water masses in the upwelling mixed water body, and the hydrogen and oxygen isotope values ​​of different end-member waters are determined based on the hydrological information and hydrogen and oxygen isotope values. Based on the different water masses in the upwelling mixture and the hydrogen and oxygen isotope values ​​in the upwelling influence zone, the isotope mass balance model is established.

3. The method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes according to claim 2, characterized in that, Obtaining hydrological information for the target sea area includes: The hydrological information was obtained using CTD detection, and the survey period was during the season when the upwelling effect was significant.

4. The method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes according to claim 3, characterized in that, Obtaining the hydrogen and oxygen isotope values ​​of the target sea area includes: Seawater samples from different layers were collected in the target sea area using a Niskin water sampler. The samples were exposed to air for the same amount of time during collection. The samples were then filled with glass bottles and sealed. Subsequently, the hydrogen and oxygen isotope values ​​of the seawater were measured using a gas stable isotope ratio mass spectrometer within a fixed time period.

5. The method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes according to claim 2, characterized in that, Identifying and distinguishing upwelling influence zones based on the relationship between temperature, salinity, and hydrogen and oxygen isotopes in water includes: Based on the planar and cross-sectional distribution maps of temperature, salinity, and hydrogen and oxygen isotopes in the target sea area, determine the surface water in the upwelling influence zone, the surface water in the non-upwelling influence zone, and the deep water in the upwelling influence zone. The surface water in the upwelling influence zone is formed by the mixture of surface water in the non-upwelling influence zone and deep water in the upwelling influence zone.

6. The method for quantifying upwelling intensity and its biogeochemical processes based on hydrogen and oxygen isotopes according to claim 5, characterized in that, The isotopic mass balance model is as follows: X h = f b × X b + f s × X s ； f b + f s = 1； In the formula, X h This represents the average hydrogen or oxygen isotope content of the surface water in the upwelling influence zone. X b The average value of hydrogen or oxygen isotopes in the surface water of the non-upwelling influence zone; X s This represents the average hydrogen or oxygen isotope value of the deep water in the upwelling influence zone. f b The proportion of surface water in the non-upwelling influence zone; f s This represents the proportion of deep water in the upwelling influence zone.

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