Method for determining and warning of extreme environmental events in shellfish farming sea areas

Abstract

The application discloses a kind of determination and early warning method of extreme environmental event in shellfish culture sea area, comprising: according to the high-density continuous collection of sea area environmental data, obtains the extreme value of environmental parameter of the day;Based on the corresponding parameter type of the environmental parameter extreme value of the day historical environmental data year set, the corresponding environmental parameter threshold value of the day is calculated;Based on the size relationship of the environmental parameter extreme value of the day and the environmental parameter threshold value, combined with duration, it is determined whether extreme environmental event occurs;According to the determination result of the extreme environmental event, decide early warning level.The present application aims to avoid the disease and death risk caused by environmental stress to cultured shellfish, improve the ability of disaster prevention and reduction.

Description

Technical Field

[0001] This invention belongs to the field of aquaculture technology, and in particular relates to a method for determining and warning of extreme environmental events in shellfish farming areas. Background Technology

[0002] Shellfish diseases are influenced by multiple factors, including pathogens, environment, and operational management. However, under the current aquaculture ecosystem, environmental stress has become the primary factor contributing to shellfish diseases and mortality. Frequent extreme environmental events significantly increase the mortality risk of farmed shellfish. "Prevention is paramount, and prevention is better than cure" is the fundamental principle of current shellfish disease control. Strengthening the monitoring, analysis, and early warning of extreme marine environmental events is a crucial path to enhancing the disaster mitigation capabilities of marine shellfish aquaculture and promoting high-quality industrial development. Research has found that high temperatures and abnormal temperature fluctuations are hallmark events leading to mortality in farmed oysters. Furthermore, wasting syndrome caused by insufficient nutrient intake, coupled with high summer temperatures, is a significant cause of oyster mortality. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention proposes a method for determining and issuing early warnings of extreme environmental events in shellfish aquaculture areas. This method aims to mitigate the risks of disease and mortality caused by environmental stress to farmed shellfish and improve the industry's ability to avoid disasters and reduce losses.

[0004] To achieve the above objectives, this invention provides a method for determining and issuing early warnings of extreme environmental events in shellfish aquaculture areas, comprising: Based on high-density, continuously collected marine environmental data, the extreme values ​​of environmental parameters for the day are obtained; Based on the set of historical environmental data years corresponding to the parameter types of the extreme values ​​of environmental parameters on that day, calculate the corresponding environmental parameter threshold for that day. Based on the relationship between the extreme values ​​of the environmental parameters on that day and the threshold values ​​of the environmental parameters, and in conjunction with the duration, it is determined whether an extreme environmental event has occurred. The warning level is determined based on the assessment of the extreme environmental events.

[0005] Optionally, the marine environmental data includes temperature, salinity, pH, dissolved oxygen, turbidity, and chlorophyll content.

[0006] Optionally, the extreme values ​​of the environmental parameters for the day include: the maximum value of the environmental parameters for the day and the minimum value of the environmental parameters for the day, wherein the maximum value of the environmental parameters for the day refers to the parameters of temperature and turbidity, and the minimum value of the environmental parameters for the day refers to the parameters of salinity, pH, dissolved oxygen and chlorophyll content.

[0007] Optionally, the maximum value of the environmental parameters for that day can be obtained. include: ; Obtain the minimum value of the environmental parameter for the day. include: ; Where Env(t) is the environmental parameter value at observation time t, and date(t) is the calendar date at time t.

[0008] Optionally, the historical environmental data year set shall include at least the environmental data of the same sea area for the past 5 years, and the historical environmental data shall be collected continuously at intervals not exceeding 1 hour.

[0009] Optionally, based on the set of historical environmental data years corresponding to the parameter types of the extreme values ​​of the environmental parameters on that day, the threshold value of the corresponding environmental parameter for that day is calculated, including: Based on the set of historical environmental data years, a 31-day sliding window consisting of 15 days before and after each date is taken, and the extreme values ​​of environmental parameters for each day within the window in all years are collected. Based on the extreme values ​​of the environmental parameters, the 90th percentile or 10th percentile of all extreme values ​​within the window is calculated and used as the corresponding environmental parameter threshold for that day.

[0010] Optionally, the 90th percentile of all extreme values ​​within the window is calculated and used as the corresponding environmental parameter threshold for that day. include: ; The 10th percentile of all extreme values ​​within the window is calculated and used as the corresponding environmental parameter threshold for that day. include: ; Where Y is the set of historical baseline data years; w is the sliding window; Env(y,d) is the extreme value of the environmental parameter in year y and day d; P(·) is the 90th or 10th percentile function; and k is the number of offset days in the sliding window, which is an integer between -w and w.

[0011] Optionally, determining whether an extreme environmental event has occurred, based on the relationship between the extreme values ​​of the environmental parameters on that day and the threshold values ​​of the environmental parameters, and in conjunction with the duration, includes: Based on the state that the maximum value of the environmental parameter on the day is greater than the corresponding environmental parameter threshold, or the minimum value of the environmental parameter on the day is less than the corresponding environmental parameter threshold, it is determined whether the limit is exceeded on that day; Whether an extreme environmental event has occurred is determined by whether the number of consecutive days exceeding the limit reaches 3 days.

[0012] Optionally, the warning level may be determined based on the assessment of the extreme environmental event, including: When the duration is greater than or equal to 3 days but less than 7 days, a mild warning is issued. When the duration is greater than or equal to 7 days but less than 15 days, a moderate warning is issued. A severe warning is issued when the duration is greater than or equal to 15 days.

[0013] Compared with the prior art, the present invention has the following advantages and technical effects: This invention employs a high-sensitivity algorithm to determine the environmental level of marine areas on a daily basis, providing beneficial early warnings for aquaculture shellfish to avoid extreme environmental risks. While improving the accuracy of judgment and early warning, it reduces the high costs and time delays caused by the cumbersome sampling and testing processes of traditional shellfish health monitoring methods for environmental stress assessment. This invention is applicable to extreme environmental events in aquaculture areas such as high temperature, low salinity, low oxygen, acidification, oligotrophic conditions, and increased turbidity, providing a scientific basis for disaster early warning and risk management in shellfish aquaculture. Attached Figure Description

[0014] 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: Figure 1 This is a flowchart of a method for determining and issuing early warnings of extreme environmental events in shellfish aquaculture areas according to an embodiment of the present invention. Detailed Implementation

[0015] 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.

[0016] 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.

[0017] This embodiment proposes a method for determining and issuing early warnings of extreme environmental events in shellfish aquaculture areas, such as... Figure 1 As shown, the specific steps include: Based on high-density, continuously collected marine environmental data, the extreme values ​​of environmental parameters for the day are obtained; Based on the set of historical environmental data years corresponding to the parameter types of the extreme values ​​of environmental parameters on that day, calculate the corresponding environmental parameter threshold for that day. Based on the relationship between the extreme values ​​of the environmental parameters on that day and the threshold values ​​of the environmental parameters, and in conjunction with the duration, it is determined whether an extreme environmental event has occurred. The warning level is determined based on the assessment of the extreme environmental events.

[0018] Specifically, it includes the following steps: Based on the high-density marine environmental data, the maximum value of the environmental parameter Envmax(d) or the minimum value Envmin(d) for the day (d) is obtained; the high-density marine environmental data is collected continuously at intervals not exceeding 1 hour. Based on the set of years Y of historical environmental data, calculate the environmental parameter threshold τ(d) for that day (d); Based on the relationship between Envmax(d) and τ(d) and their duration, it is determined whether an extreme environmental event has occurred; The warning level is determined based on the assessment of extreme environmental events.

[0019] The method for determining and issuing early warnings of extreme environmental events in shellfish aquaculture areas in this embodiment uses the environmental data of the marine area continuously monitored for the most recent (at least) 5 years as historical benchmark data and the environmental data monitored in real time with high density as determination data. By comparing the extreme values ​​of environmental parameters on the day with the percentile thresholds (the maximum value parameter is taken as the 90th percentile and the minimum value parameter is taken as the 10th percentile) calculated based on a sliding window of historical data (15 days before and after), and combining the number of days the extreme conditions last (≥3 days), the occurrence of extreme environmental events is determined, and then mild, moderate and severe warning levels are given according to the duration (3-7 days, 7-15 days, ≥15 days).

[0020] Furthermore, the marine environmental data includes temperature, salinity, pH, dissolved oxygen, turbidity, and chlorophyll content.

[0021] Furthermore, the extreme values ​​of the environmental parameters for the day include: the maximum value of the environmental parameters for the day and the minimum value of the environmental parameters for the day, wherein the parameters for the maximum value of the environmental parameters for the day are temperature and turbidity, and the parameters for the minimum value of the environmental parameters for the day are salinity, pH, dissolved oxygen and chlorophyll content.

[0022] Furthermore, the maximum value of the environmental parameters for that day is obtained. include: ; Obtain the minimum value of the environmental parameter for the day. include: ; Where Env(t) is the environmental parameter value at observation time t, and date(t) is the calendar date at time t.

[0023] Furthermore, the historical environmental data year set includes at least the environmental data of the same sea area for the past 5 years, and the historical environmental data is collected continuously at intervals not exceeding 1 hour.

[0024] Specifically, the set of years Y of the historical environmental data includes at least environmental data from the same sea area collected at 1-hour or 30-minute intervals over the past 5 years.

[0025] Furthermore, based on the set of historical environmental data years corresponding to the parameter types of the extreme values ​​of the environmental parameters on that day, the threshold values ​​of the corresponding environmental parameters for that day are calculated as follows: Based on the set of historical environmental data years, a 31-day sliding window consisting of 15 days before and after each date is taken, and the extreme values ​​of environmental parameters for each day within the window in all years are collected. Based on the extreme values ​​of the environmental parameters, the 90th percentile or 10th percentile of all extreme values ​​within the window is calculated and used as the corresponding environmental parameter threshold for that day.

[0026] Furthermore, the 90th percentile of all extreme values ​​within the window is calculated and used as the corresponding environmental parameter threshold for that day. include: ; The 10th percentile of all extreme values ​​within the window is calculated and used as the corresponding environmental parameter threshold for that day. include: ; Where Y is the set of historical baseline data years; w is the sliding window; Env(y,d) is the extreme value of the environmental parameter in year y and day d; P(·) is the 90th or 10th percentile function; and k is the number of offset days in the sliding window, which is an integer between -w and w.

[0027] Furthermore, based on the relationship between the extreme values ​​of the environmental parameters on that day and the threshold values ​​of the environmental parameters, and in conjunction with the duration, determining whether an extreme environmental event has occurred includes: Based on the state that the maximum value of the environmental parameter on the day is greater than the corresponding environmental parameter threshold, or the minimum value of the environmental parameter on the day is less than the corresponding environmental parameter threshold, it is determined whether the limit is exceeded on that day; Whether an extreme environmental event has occurred is determined by whether the number of consecutive days exceeding the limit reaches 3 days.

[0028] Furthermore, based on the determination of the extreme environmental event, the warning level is determined as follows: When the duration is greater than or equal to 3 days but less than 7 days, a mild warning is issued. When the duration is greater than or equal to 7 days but less than 15 days, a moderate warning is issued. A severe warning is issued when the duration is greater than or equal to 15 days.

[0029] Specifically, the criteria for determining an extreme environmental event are: 1) for the maximum parameter, Envmax(d) > τmax(d), and for the minimum parameter, Envmin(d) < τmin(d); and 2) the duration is at least 3 days.

[0030] That is, there exist continuous date sequences d, d+1, ..., d+L-1 (L≥3) such that: ; or .

[0031] The warning level is determined based on the assessment of extreme environmental events, using the following method: If Envmax(d)≤τmax(d) (or Envmin(d)≤τmin(d)), there are no extreme environmental events; If Envmax(d) > τmax(d) (or Envmin(d) ≤ τmin(d)) and L < 3, there are no extreme environmental events; If Envmax(d)>τmax(d) (or Envmin(d)≤τmin(d)) and 3≤L<7, an extreme environmental event will occur, and a mild warning is recommended. If Envmax(d)>τmax(d) (or Envmin(d)≤τmin(d)) and 7≤L<15, an extreme environmental event will occur, and a moderate warning is recommended. If Envmax(d) > τ(d) (or Envmin(d) ≤ τ(d)) and L ≥ 15, an extreme environmental event will occur, and a severe warning is recommended.

[0032] Using five years of continuous temperature data (2020-2024) collected at 30-minute intervals in the main oyster farming area of ​​Rushan as the baseline environmental data year set Y, and using continuous temperature data collected at 30-minute intervals in 2025 as the target data, the abnormal high-temperature event in 2025 was determined. Envmax(d) and τmax(d) were calculated using the following formulas: ; ; The following formula can be used to determine whether an extreme environmental event exists: ; Calculations indicate three extreme temperature events in 2025: January 20-27, lasting 8 days; July 22-30, lasting 9 days; and August 19-September 2, lasting 15 days. Based on warning standards, moderate, severe, and high-level warnings can be implemented respectively.

[0033] 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 determining and issuing early warning of extreme environmental events in shellfish aquaculture areas, characterized in that, include: Based on high-density, continuously collected marine environmental data, the extreme values ​​of environmental parameters for the day are obtained; Based on the set of historical environmental data years corresponding to the parameter types of the extreme values ​​of environmental parameters on that day, calculate the corresponding environmental parameter threshold for that day. Based on the relationship between the extreme values ​​of the environmental parameters on that day and the threshold values ​​of the environmental parameters, and in conjunction with the duration, it is determined whether an extreme environmental event has occurred. The warning level is determined based on the assessment of the extreme environmental events.

2. The method for determining and issuing early warning of extreme environmental events in shellfish aquaculture areas according to claim 1, characterized in that, The marine environmental data includes temperature, salinity, pH, dissolved oxygen, turbidity, and chlorophyll content.

3. The method for determining and issuing early warning of extreme environmental events in shellfish aquaculture areas according to claim 2, characterized in that, The extreme values ​​of environmental parameters for the day include: the maximum value of environmental parameters for the day and the minimum value of environmental parameters for the day. The parameters for which the maximum value of environmental parameters for the day refers to the temperature and turbidity, and the parameters for which the minimum value of environmental parameters for the day refers to the salinity, pH, dissolved oxygen and chlorophyll content.

4. The method for determining and issuing early warning of extreme environmental events in shellfish aquaculture areas according to claim 3, characterized in that, Obtain the maximum value of the environmental parameters for that day. include: ； Obtain the minimum value of the environmental parameter for the day. include: ； Where Env(t) is the environmental parameter value at observation time t, and date(t) is the calendar date at time t.

5. The method for determining and issuing early warning of extreme environmental events in shellfish aquaculture areas according to claim 1, characterized in that, The historical environmental data year set shall include environmental data of the same sea area for at least the past 5 years, and the historical environmental data shall be collected continuously at intervals not exceeding 1 hour.

6. The method for determining and issuing early warning of extreme environmental events in shellfish aquaculture areas according to claim 3, characterized in that, Based on the set of historical environmental data years corresponding to the parameter types of the extreme values ​​of environmental parameters on that day, the threshold values ​​of environmental parameters for that day are calculated as follows: Based on the set of historical environmental data years, a 31-day sliding window consisting of 15 days before and after each date is taken, and the extreme values ​​of environmental parameters for each day within the window in all years are collected. Based on the extreme values ​​of the environmental parameters, the 90th percentile or 10th percentile of all extreme values ​​within the window is calculated and used as the corresponding environmental parameter threshold for that day.

7. The method for determining and issuing early warning of extreme environmental events in shellfish aquaculture areas according to claim 6, characterized in that, The 90th percentile of all extreme values ​​within the window is calculated and used as the corresponding environmental parameter threshold for that day. include: ； The 10th percentile of all extreme values ​​within the window is calculated and used as the corresponding environmental parameter threshold for that day. include: ； Where Y is the set of historical baseline data years; w is the sliding window; Env(y,d) is the extreme value of the environmental parameter in year y and day d; P(·) is the 90th or 10th percentile function; and k is the number of offset days in the sliding window, which is an integer between -w and w.

8. The method for determining and issuing early warning of extreme environmental events in shellfish aquaculture areas according to claim 3, characterized in that, Based on the relationship between the extreme values ​​of the environmental parameters on that day and the threshold values ​​of the environmental parameters, and in conjunction with the duration, determining whether an extreme environmental event has occurred includes: Based on the state that the maximum value of the environmental parameter on the day is greater than the corresponding environmental parameter threshold, or the minimum value of the environmental parameter on the day is less than the corresponding environmental parameter threshold, it is determined whether the limit is exceeded on that day; Whether an extreme environmental event has occurred is determined by whether the number of consecutive days exceeding the limit reaches 3 days.

9. The method for determining and issuing early warning of extreme environmental events in shellfish aquaculture areas according to claim 3, characterized in that, Based on the determination of the extreme environmental events, the warning levels are determined as follows: When the duration is greater than or equal to 3 days but less than 7 days, a mild warning is issued. When the duration is greater than or equal to 7 days but less than 15 days, a moderate warning is issued. A severe warning is issued when the duration is greater than or equal to 15 days.

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