Growth model and life cycle evaluation macroalgae carbon footprint evaluation method

Abstract

The invention discloses a macroalgae carbon footprint evaluation method for growth model and life cycle evaluation. The macroalgae carbon footprint evaluation method comprises the following steps: S1, determining a research purpose, a system boundary and a function unit; s2, dynamically coupling the growth process and the carbon sink mechanism of the macroalgae, and obtaining natural process carbon footprint data; s3, collecting industrial process carbon footprint data and constructing a front-end data list; s4, carrying out modeling evaluation by utilizing openLCA (Open LCA) software and an Ecoinvent3.8 database; s5, analyzing a result and identifying a key discharge process and a material flow; according to the method, a dynamic growth model of the macroalgae is combined with a full-life-cycle method for the first time, so that a natural process and an industrial process are brought into a unified carbon evaluation system, dynamic correction of natural environment factors on the carbon footprint is realized, scientificity and accuracy of carbon footprint evaluation of the macroalgae culture system are improved, and the carbon footprint evaluation efficiency is improved. And a technical method is provided for optimizing a large seaweed culture process and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon footprint, and in particular to a growth model and a life cycle assessment method for large seaweed carbon footprint. Background Art

[0002] Large seaweed is regarded as one of the core carriers of marine negative emission technology due to its efficient photosynthetic carbon fixation ability and huge potential for large-scale cultivation.

[0003] During the growth process, algae absorb dissolved carbon in the water through the growth of biomass, forming a biological carbon sink; however, various industrial activities in the aquaculture industry chain, such as energy consumption, construction of production facilities, and transportation and processing, will produce significant carbon emissions. The current existing assessment methods have obvious limitations: first, the traditional life cycle assessment (LCA) only focuses on the accounting of carbon emissions generated by industrial processes, while ignoring the dynamic balance of carbon absorption and release by algae during the natural growth stage; second, although some studies have attempted to include biological carbon fixation in the assessment scope, a dynamic coupling model of algae growth and carbon sink has not yet been established, especially the serious lack of analysis of the response mechanism of regional environmental factors such as water temperature, light, and nutrient gradients, making it difficult to truly and accurately reflect the impact of natural environmental fluctuations on carbon footprints. Summary of the invention

[0004] To solve the above problems, the present invention proposes a large-scale seaweed carbon footprint assessment method based on a growth model and life cycle assessment. This method combines the growth process of large-scale seaweed with the carbon footprint mechanism, incorporates natural processes and industrial processes into a unified carbon footprint assessment framework, and realizes carbon footprint analysis of the entire life cycle, which can improve the accuracy of carbon footprint assessment of large-scale seaweed cultivation systems.

[0005] To achieve the above object, the present invention adopts the following technical solutions: A method for evaluating the carbon footprint of macroalgae based on growth model and life cycle assessment, comprising the following steps: S1. Determine the research purpose, system boundaries and functional units; S2. Dynamically couple the growth process of large seaweed with the carbon sink mechanism to obtain carbon footprint data of natural processes; The growth model of large seaweed simulates the dynamic accumulation process of biomass and provides key parameters to quantify the CO2 absorbed by large seaweed through photosynthesis and evaluate the long-term carbon fixation capacity of large seaweed. It includes the following steps: S21. Establish a biomass dynamic model and calculate the rate of change of large algae biomass per unit area over time through differential equations. The calculation formula is: , where is the rate of change of large seaweed biomass per unit area over time; B is the large seaweed biomass per unit area; is the net growth rate; is the erosion rate; S22. Calculate the net growth rate using the formula: , , , where is the total growth rate; is the respiratory rate; is the maximum respiration rate at 20°C; is the empirical coefficient; is the sea water temperature; is the maximum growth rate; , and are the limiting functions of water temperature, light intensity and nutrient concentration respectively; S23. Calculate the carbon fixation amount using the following formula: , , where is the final dry weight of macroalgae per unit area; is the initial dry weight of macroalgae per unit area; t is the time; is the amount of carbon fixed by macroalgae per unit area; is the carbon content ratio; is the unit time; S24. Calculate the net primary productivity using the formula: , where is the net primary productivity; is the organic carbon of debris particles per unit area; is the dissolved organic carbon released by seaweed per unit area; S25. Calculate the inert dissolved organic carbon using the formula: , where is the inert dissolved organic carbon; a is the coefficient of dissolved organic carbon released by seaweed to form inert dissolved organic carbon; S26. Calculate the carbon buried in the algae bed using the following formula: , where burying carbon for algal beds; is the daily sedimentation rate of sediment organic carbon; is the total organic carbon content of the sediment; is the proportion of organic carbon of macroalgae in the total organic carbon of sediments; S27. Calculate the buried carbon on the continental shelf using the following formula: , where burying carbon for the shelf; is the proportion factor of debris buried on the shelf; S28. Calculate deep sea transport carbon using the following formula: , where delivering carbon to the deep ocean; is the ratio coefficient of debris transport to the deep sea; S29. Calculate the total carbon footprint generated by natural processes using the following formula: 1000, where The total carbon footprint produced by natural processes to grow 1 ton of macroalgae; is the conversion coefficient of CO2 to C, Select 3.67; S3, collect industrial process carbon footprint data and build a front-end data inventory; Through field research and database integration, the industrial process carbon footprint data of the entire chain of large-scale seaweed aquaculture systems are obtained. The industrial process carbon footprint data includes energy flow data, material flow data and transportation flow data; the front-end data comes from the field research of aquaculture enterprises or farmers, and the back-end data is extracted from the Ecoinvent v3.8 database and corrected by localization factors; based on the industrial process carbon footprint data, front-end data and back-end data, a full life cycle inventory of social industrial processes is constructed, and the total carbon footprint generated by social industrial processes is calculated. The calculation formula is: , where The total carbon footprint of the socio-industrial process for the cultivation of 1 tonne of fresh weight of macroalgae; is the consumption of the i-th resource or energy; is the emission factor of the i-th resource or energy; i is the type of resource or energy invested in the social industrial process; n is the total number of resource or energy types; S4, modeling and evaluation using openLCA software and Ecoinvent 3.8 database; Based on the inventory data, the life cycle assessment method was used to model the large-scale seaweed aquaculture system. The Ecoinvent 3.8 database was integrated through the openLCA software to optimize the regional characteristic parameters, and the global warming indicators in the ReCipe 2016v1.1Midpoint database were used to carry out the life cycle carbon footprint assessment. The total carbon footprint of the coupled natural and social systems of large-scale seaweed farming is calculated as: , where the total carbon footprint of coupled natural and social systems for macroalgae farming; The calculated result is positive, which means that the total process of large seaweed farming is a carbon source; The calculated result is negative, which means that the total process of large seaweed farming is a carbon sink; S5. Analyze the results and identify key emission processes and material flows.

[0006] Preferably, the research purpose in step S1 is to combine the dynamic growth model of large seaweed with the whole life cycle approach, incorporate natural processes and industrial processes into a unified carbon assessment system, and construct a carbon footprint assessment method for large seaweed cultivation systems; the system boundary is all life cycle stages of large seaweed from seedlings to harvest; and the functional unit is the production of 1 ton of fresh weight of cultured kelp, laver or sea urchin.

[0007] Preferably, the erosion rate in step S21 is determined by measuring the loss rate of the top leaves of the seaweed on site; in step S22, the water temperature and nutrient concentration data are obtained from literature, monitoring stations or field experiments, and the light intensity and seawater temperature are simulated according to the functional relationship fitted by the longitude and latitude of the local sea area; in step S23, the final dry weight and initial dry weight of the large seaweed per unit area are measured by drying and weighing, and the carbon content ratio is obtained by measuring the carbon content ratio in the large seaweed; in step S24, the organic carbon of the debris particles is measured by filtering and collecting the debris particles, and then the organic carbon content is determined by an element analyzer; the dissolved organic carbon released by the seaweed is measured by filtering and separating the dissolved part, and the total organic carbon analyzer is used for determination; the determination of the coefficient a in step S25 is based on the release of the seaweed. The long-term transformation experiment of dissolved organic carbon in water bodies is carried out to statistically obtain the proportion of inert dissolved organic carbon; the daily sedimentation rate of sediment organic carbon in step S26 is measured by using a sediment trap for long-term monitoring in the sea area of ​​​​the seabed, and the sedimentation amount of sediment organic carbon per unit time is calculated; the coefficient b is determined by elemental analysis of sediment samples to obtain the total organic carbon content; the coefficient c is determined by tracing the source of organic carbon in the sediment to calculate the proportion of large seaweed organic carbon; the coefficient d in step S27 is determined based on the study of the source of debris in shelf sediments, and the proportion of large seaweed debris buried on the shelf is statistically calculated; the coefficient e in step S28 is determined by studying ocean circulation and sediment transport, and calculating the proportion of large seaweed debris transported to the deep sea.

[0008] Preferably, in step S3, the field survey adopts a combination of questionnaire surveys, on-site observations and interviews to improve the accuracy and completeness of the social industrial process data of the breeding system; then the parameters are adjusted according to the local energy structure, production technology and transportation methods to make the database data more in line with local actual conditions; when constructing the full life cycle inventory of the social industrial process, the input-output analysis method is used to classify and summarize the data according to the life cycle stage.

[0009] Preferably, the specific process of modeling the large seaweed cultivation system using the life cycle assessment method in step S4 is: constructing a full life cycle model based on the unit data of different stages of large seaweed cultivation, including the functional units, system boundaries, and unit processes of different stages defined in the early stage, and selecting the global warming index in the ReCiPe 2016v1.1 Midpoint life cycle impact assessment software to conduct an impact assessment on the constructed full life cycle model, and calculate the carbon footprint of each stage.

[0010] Preferably, the specific process of step S5 is: analyzing the overall carbon footprint of the large-scale seaweed cultivation system under the coupling of natural and industrial processes, accurately locating the key influencing factors, optimizing the cultivation mode according to the actual cultivation production conditions and processes, and enhancing the carbon fixation and sink capacity of the large-scale seaweed cultivation system.

[0011] After adopting the above technical scheme, the present invention has the following beneficial effects: the present invention combines the dynamic growth model of large seaweed with the whole life cycle method for the first time, so that natural processes (algal carbon absorption / release) and industrial processes (carbon emissions from energy and material consumption) are included in a unified carbon assessment system. Compared with the limitations of traditional methods that separately account for biological carbon fixation and industrial carbon emissions, this method realizes the dynamic correction of carbon footprint by natural environmental factors (such as regional temperature fields and nutrient gradients), improves the scientificity and accuracy of carbon footprint assessment of large seaweed cultivation systems, and provides technical methods for optimizing large seaweed cultivation processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0013] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0014] like Figure 1 As shown, a method for evaluating the carbon footprint of macroalgae based on a growth model and life cycle assessment includes the following steps: S1. Determine the research purpose, system boundaries and functional units; The research purpose described in step S1 is to combine the dynamic growth model of large seaweed with the whole life cycle method, so as to incorporate natural processes and industrial processes into a unified carbon assessment system and construct a carbon footprint assessment method for large seaweed aquaculture systems; the system boundary is all life cycle stages of large seaweed from seedlings to harvest; the functional unit is the production of 1 ton of fresh weight of cultured kelp, laver or kelp; S2. Dynamically couple the growth process of large seaweed with the carbon sink mechanism to obtain carbon footprint data of natural processes; The growth model of large seaweed simulates the dynamic accumulation process of biomass and provides key parameters to quantify the CO2 absorbed by large seaweed through photosynthesis and evaluate the long-term carbon fixation capacity of large seaweed. It includes the following steps: S21. Establish a biomass dynamic model and calculate the rate of change of large algae biomass per unit area over time through differential equations. The calculation formula is: , where is the rate of change of large seaweed biomass per unit area over time; B is the large seaweed biomass per unit area; is the net growth rate; is the erosion rate; S22. Calculate the net growth rate using the formula: , , , where is the total growth rate; is the respiratory rate; is the maximum respiration rate at 20°C; is the empirical coefficient; is the sea water temperature; is the maximum growth rate; , and are the limiting functions of water temperature, light intensity and nutrient concentration respectively; S23. Calculate the carbon fixation amount using the following formula: , , where is the final dry weight of macroalgae per unit area; is the initial dry weight of macroalgae per unit area; t is the time; is the amount of carbon fixed by macroalgae per unit area; is the carbon content ratio; is the unit time; S24. Calculate the net primary productivity using the formula: , where is the net primary productivity; is the organic carbon of debris particles per unit area; is the dissolved organic carbon released by seaweed per unit area; S25. Calculate the inert dissolved organic carbon using the formula: , where is the inert dissolved organic carbon; a is the coefficient of dissolved organic carbon released by seaweed to form inert dissolved organic carbon; S26. Calculate the carbon buried in the algae bed using the following formula: , where burying carbon for algal beds; is the daily sedimentation rate of sediment organic carbon; is the total organic carbon content of the sediment; is the proportion of organic carbon of macroalgae in the total organic carbon of sediments; S27. Calculate the buried carbon on the continental shelf using the following formula: , where burying carbon for the shelf; is the proportion factor of debris buried on the shelf; S28. Calculate deep sea transport carbon using the following formula: , where delivering carbon to the deep ocean; is the ratio coefficient of debris transport to the deep sea; S29. Calculate the total carbon footprint generated by natural processes using the following formula: 1000, where The total carbon footprint produced by natural processes to grow 1 ton of macroalgae; is the conversion coefficient of CO2 to C, Select 3.67; The erosion rate in step S21 is determined by measuring the loss rate of the top leaves of the seaweed on site; in step S22, the water temperature and nutrient concentration data are obtained from literature, monitoring stations or field experiments, and the light intensity and seawater temperature are simulated according to the functional relationship fitted by the longitude and latitude of the local sea area; in step S23, the final dry weight and initial dry weight of the large seaweed per unit area are measured by drying and weighing, and the carbon content ratio is obtained by measuring the carbon content ratio in the large seaweed; in step S24, the organic carbon of the debris particles is measured by filtering and collecting the debris particles, and then the organic carbon content is determined by an element analyzer; the dissolved organic carbon released by the seaweed is measured by filtering and separating the dissolved part, and the total organic carbon analyzer is used for determination; the coefficient a in step S25 is determined based on the dissolved carbon released by the seaweed. The long-term transformation experiment of organic carbon in water is conducted to obtain the proportion of inert dissolved organic carbon; the daily sedimentation rate of organic carbon in sediments in step S26 is measured by long-term monitoring in the sea area of ​​​​algae beds using a sediment trap to calculate the sedimentation amount of organic carbon in sediments per unit time; the coefficient b is determined by elemental analysis of sediment samples to obtain the total organic carbon content; the coefficient c is determined by tracing the source of organic carbon in sediments to calculate the proportion of organic carbon in large seaweeds; the coefficient d in step S27 is determined based on the study of the source of debris in shelf sediments, and the proportion of large seaweed debris buried on the shelf is counted; the coefficient e in step S28 is determined by studying ocean circulation and sediment transport, and calculating the proportion of large seaweed debris transported to the deep sea; S3, collect industrial process carbon footprint data and build a front-end data inventory; Through field research and database integration, the industrial process carbon footprint data of the entire chain of large-scale seaweed aquaculture systems are obtained. The industrial process carbon footprint data includes energy flow data, material flow data and transportation flow data; the front-end data comes from the field research of aquaculture enterprises or farmers, and the back-end data is extracted from the Ecoinvent v3.8 database and corrected by localization factors; based on the industrial process carbon footprint data, front-end data and back-end data, a full life cycle inventory of social industrial processes is constructed, and the total carbon footprint generated by social industrial processes is calculated. The calculation formula is: , where The total carbon footprint of the socio-industrial process for the cultivation of 1 tonne of fresh weight of macroalgae; is the consumption of the i-th resource or energy; is the emission factor of the i-th resource or energy; i is the type of resource or energy invested in the social industrial process; n is the total number of resource or energy types; In step S3, the field survey adopts a combination of questionnaire survey, on-site observation and interview to improve the accuracy and completeness of the social industrial process data of the aquaculture system; then the parameters are adjusted according to the local energy structure, production technology and transportation mode to make the database data more in line with the local actual situation; when constructing the full life cycle inventory of the social industrial process, the input-output analysis method is used to classify and summarize the data according to the life cycle stage; S4, modeling and evaluation using openLCA software and Ecoinvent 3.8 database; Based on the inventory data, the life cycle assessment method was used to model the large-scale seaweed aquaculture system. The Ecoinvent 3.8 database was integrated through the openLCA software to optimize the regional characteristic parameters, and the global warming indicators in the ReCipe 2016v1.1Midpoint database were used to carry out the life cycle carbon footprint assessment. The total carbon footprint of the coupled natural and social systems of large-scale seaweed farming is calculated as: , where the total carbon footprint of coupled natural and social systems for macroalgae farming; The calculated result is positive, which means that the total process of large seaweed farming is a carbon source; The calculated result is negative, which means that the total process of large seaweed farming is a carbon sink; The specific process of modeling the large-scale seaweed farming system using the life cycle assessment method in step S4 is as follows: constructing a full life cycle model based on the unit data of different stages of large-scale seaweed farming, including the functional units, system boundaries, and unit processes at different stages defined in the early stage, and selecting the global warming index in the ReCiPe 2016v1.1 Midpoint life cycle impact assessment software to conduct an impact assessment on the constructed full life cycle model, and calculate the carbon footprint of each stage; S5. Analyze the results and identify key emission processes and material flows; The specific process of step S5 is: analyzing the overall carbon footprint of large-scale seaweed cultivation systems under the coupling of natural and industrial processes, accurately locating key influencing factors, optimizing the cultivation model according to actual cultivation production conditions and processes, and enhancing the carbon fixation and sink capacity of large-scale seaweed cultivation systems.

[0015] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A growth model and life cycle assessment method for large seaweed carbon footprint assessment, characterized in that: The following steps are involved: S1. Determine the research purpose, system boundaries and functional units; S2. Dynamically couple the growth process of large seaweed with the carbon sink mechanism to obtain carbon footprint data of natural processes; The growth model of large seaweed simulates the dynamic accumulation process of biomass and provides key parameters to quantify the CO2 absorbed by large seaweed through photosynthesis and evaluate the long-term carbon fixation capacity of large seaweed. It includes the following steps: S21. Establish a biomass dynamic model and calculate the rate of change of large algae biomass per unit area over time through differential equations. The calculation formula is: , where is the rate of change of large seaweed biomass per unit area over time; B is the large seaweed biomass per unit area; is the net growth rate; is the erosion rate; S22. Calculate the net growth rate using the formula: , , , where is the total growth rate; is the respiratory rate; is the maximum respiration rate at 20°C; is the empirical coefficient; is the sea water temperature; is the maximum growth rate; , and are the limiting functions of water temperature, light intensity and nutrient concentration respectively; S23. Calculate the carbon fixation amount using the following formula: , , where is the final dry weight of macroalgae per unit area; is the initial dry weight of macroalgae per unit area; t is the time; is the amount of carbon fixed by macroalgae per unit area; is the carbon content ratio; is the unit time; S24. Calculate the net primary productivity using the formula: , where is the net primary productivity; is the organic carbon of debris particles per unit area; is the dissolved organic carbon released by seaweed per unit area; S25. Calculate the inert dissolved organic carbon using the formula: , where is the inert dissolved organic carbon; a is the coefficient of dissolved organic carbon released by seaweed to form inert dissolved organic carbon; S26. Calculate the carbon buried in the algae bed using the following formula: , where burying carbon for algal beds; is the daily sedimentation rate of sediment organic carbon; is the total organic carbon content of the sediment; is the proportion of organic carbon of macroalgae in the total organic carbon of sediments; S27. Calculate the buried carbon on the continental shelf using the following formula: , where burying carbon for the shelf; is the proportion factor of debris buried on the shelf; S28. Calculate deep sea transport carbon using the following formula: , where delivering carbon to the deep ocean; is the ratio coefficient of debris transport to the deep sea; S29. Calculate the total carbon footprint generated by natural processes using the following formula: 1000, where The total carbon footprint produced by natural processes to grow 1 ton of macroalgae; is the conversion coefficient of CO2 to C, Select 3.67; S3, collect industrial process carbon footprint data and build a front-end data inventory; Through field research and database integration, the industrial process carbon footprint data of the entire chain of large-scale seaweed aquaculture systems are obtained. The industrial process carbon footprint data includes energy flow data, material flow data and transportation flow data; the front-end data comes from the field research of aquaculture enterprises or farmers, and the back-end data is extracted from the Ecoinvent v3.8 database and corrected by localization factors; based on the industrial process carbon footprint data, front-end data and back-end data, a full life cycle inventory of social industrial processes is constructed, and the total carbon footprint generated by social industrial processes is calculated. The calculation formula is: , where The total carbon footprint of the socio-industrial process for the cultivation of 1 tonne of fresh weight of macroalgae; is the consumption of the i-th resource or energy; is the emission factor of the i-th resource or energy; i is the type of resource or energy invested in the social industrial process; n is the total number of resource or energy types; S4, modeling and evaluation using openLCA software and Ecoinvent 3.8 database; Based on the inventory data, the life cycle assessment method was used to model the large-scale seaweed aquaculture system. The Ecoinvent 3.8 database was integrated through the openLCA software to optimize the regional characteristic parameters, and the global warming indicator in the ReCipe 2016v1.1 Midpoint database was used to carry out the life cycle carbon footprint assessment. The total carbon footprint of the coupled natural and social systems of large-scale seaweed farming is calculated as: , where the total carbon footprint of coupled natural and social systems for macroalgae farming; The calculated result is positive, which means that the total process of large seaweed farming is a carbon source; The calculated result is negative, which means that the total process of large seaweed farming is a carbon sink; S5. Analyze the results and identify key emission processes and material flows.

2. A growth model and life cycle assessment method for large seaweed carbon footprint as claimed in claim 1, characterized in that: The research purpose described in step S1 is to combine the dynamic growth model of large seaweed with the whole life cycle method, so as to incorporate natural processes and industrial processes into a unified carbon assessment system and construct a carbon footprint assessment method for large seaweed aquaculture systems; the system boundary is all life cycle stages of large seaweed from seedlings to harvest; The functional unit is the output of 1 ton of fresh weight of cultured kelp, laver or river kelp.

3. The method for evaluating the carbon footprint of large seaweed using a growth model and life cycle assessment as claimed in claim 1, characterized in that: The erosion rate in step S21 is determined by measuring the loss rate of the top leaves of the seaweed on site; in step S22, the water temperature and nutrient concentration data are obtained from literature, monitoring stations or field experiments, and the light intensity and seawater temperature are simulated according to the functional relationship fitted by the longitude and latitude of the local sea area; in step S23, the final dry weight and initial dry weight of the large seaweed per unit area are measured by drying and weighing, and the carbon content ratio is obtained by measuring the carbon content ratio in the large seaweed; in step S24, the organic carbon of the debris particles is measured by filtering and collecting the debris particles, and then using an element analyzer Determine the organic carbon content; the dissolved organic carbon released by the seaweed is measured by filtering and separating the dissolved part, and measuring it using a total organic carbon analyzer; the determination of coefficient a in step S25 is based on the long-term transformation experiment of dissolved organic carbon released by the seaweed in the water body, and the proportion of inert dissolved organic carbon is obtained by statistically analyzing the formation; the daily sedimentation rate of organic carbon in the sediment in step S26 is measured by using a sediment trap to conduct long-term monitoring in the sea area of ​​the algae bed, and the sedimentation amount of organic carbon in the sediment per unit time is calculated; the coefficient b is determined by performing elemental analysis on the sediment sample to obtain the total organic carbon content; The coefficient c is determined by tracing the source of organic carbon in the sediments and calculating the proportion of organic carbon in large seaweeds; the coefficient d in step S27 is determined based on the study of the source of debris in shelf sediments and the statistical proportion of large seaweed debris buried on the shelf; the coefficient e in step S28 is determined by studying ocean circulation and sediment transport and calculating the proportion of large seaweed debris transported to the deep sea.

4. The method for evaluating the carbon footprint of large seaweed using a growth model and life cycle assessment as claimed in claim 1, characterized in that: In step S3, the field survey adopts a combination of questionnaire survey, on-site observation and interview to improve the accuracy and completeness of the social industrial process data of the aquaculture system; and then adjust the parameters according to the local energy structure, production technology and transportation mode to make the database data more in line with the local actual situation; When constructing the full life cycle inventory of social industrial processes, the input-output analysis method is used to classify and summarize the data according to the life cycle stage.

5. The method for evaluating the carbon footprint of large seaweed using a growth model and life cycle assessment as claimed in claim 1, characterized in that: The specific process of modeling the large-scale seaweed farming system using the life cycle assessment method in step S4 is as follows: a full life cycle model is constructed based on the unit data of different stages of large-scale seaweed farming, including the functional units, system boundaries, and unit processes at different stages defined in the early stage. At the same time, the global warming index in the ReCiPe 2016v1.1 Midpoint life cycle impact assessment software is selected to conduct an impact assessment on the constructed full life cycle model, and the carbon footprint of each stage is calculated.

6. The method for evaluating the carbon footprint of large seaweed using a growth model and life cycle assessment as claimed in claim 1, characterized in that: The specific process of step S5 is: analyzing the overall carbon footprint of large-scale seaweed cultivation systems under the coupling of natural and industrial processes, accurately locating key influencing factors, optimizing the cultivation model according to actual cultivation production conditions and processes, and enhancing the carbon fixation and sink capacity of large-scale seaweed cultivation systems.

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