An ecological damage assessment system based on pollution diffusion simulation

Abstract

This invention discloses an ecological damage assessment system based on pollution diffusion simulation, relating to the technical field of marine ecological security. The system includes: an oil spill sensing monitoring network with multiple buoy probes deployed on the water surface, centered on the berth of a wharf; each buoy probe has a built-in communication device that wirelessly transmits the collected information to a data analysis module; the data analysis module constructs a computational grid based on the oil spill sensing monitoring network and maps each buoy probe to a grid node, obtaining the continuous spatial field of the entire area using Kriging interpolation; the data analysis module constructs a pollution diffusion equation and solves for the pollution concentration field; the data analysis module defines the real-time ecological damage rate and the cumulative ecological damage amount and continuously sends them to an early warning module; the early warning module triggers a prevention and control mechanism based on a comparison of these two values ​​with a preset threshold.

Description

Technical Field

[0001] This invention relates to the technical field of marine ecological security, and more specifically, to an ecological damage assessment system based on pollution diffusion simulation. Background Technology

[0002] With the continuous growth of maritime oil transportation, accidents such as oil tanker spills and pipeline leaks occur frequently, posing a serious threat to the marine ecological environment and coastal economies. Currently, common methods for monitoring marine oil spills mainly rely on shore-based radar remote sensing, satellite imagery, and fixed-point or fixed-line observations using sensors carried on ships. These methods have the following shortcomings:

[0003] Limited monitoring coverage: shore-based radar and satellite remote sensing are affected by factors such as weather, sea conditions and cloud cover, making it difficult to guarantee all-weather, blind-spot-free monitoring; shipborne cruise observation is constrained by the route and the monitoring nodes are sparsely distributed, making it impossible to obtain real-time information on the distribution of oil slicks over a wide area.

[0004] Data timeliness is delayed: conventional image acquisition, transmission, and manual analysis take time, making it difficult to reflect the pollution diffusion process in a timely manner; offline sampling and laboratory analysis have long cycles, making it difficult to meet the requirements for rapid response.

[0005] The assessment model is simplified and crude: Traditional diffusion models usually assume that the horizontal diffusion coefficient is constant and ignore the influence of marine heterogeneity such as wind, waves, temperature and salinity on the diffusion process, making it difficult to accurately characterize high concentration abrupt change zones and pollution peak effects.

[0006] Insufficient ecological damage assessment: Existing systems mostly remain at the level of concentration field monitoring, relying solely on threshold alarms, and lack assessment methods that quantify ecological damage from concentration, making it difficult to provide a scientific basis for subsequent rescue and restoration decisions. Summary of the Invention

[0007] The purpose of this invention is to construct a marine oil spill ecological damage assessment system based on pollution diffusion simulation, to achieve real-time monitoring of the spatiotemporal concentration field of pollutants and quantitative assessment of ecological damage, and to automatically issue early warnings and responses when the damage exceeds the limit.

[0008] The technical solution of the present invention is: to provide an ecological damage assessment system based on pollution diffusion simulation, the system comprising: an oil spill sensor monitoring network, a data analysis module and an early warning module;

[0009] The oil spill sensing and monitoring network consists of multiple buoy probes deployed on the water surface with the center of the berth at the wharf as the origin. Several buoy probes are grouped and distributed on multiple concentric rings with the origin as the center, forming an oil spill sensing and monitoring network. Each buoy probe has a built-in communication device to wirelessly transmit the collected information to the data analysis module.

[0010] The data analysis module constructs a computational grid based on the oil spill sensor monitoring network and maps the film thickness h, latitude surface velocity u, longitude surface velocity v, wave height H, and wave period T collected by each buoy probe to the grid nodes. The continuous spatial field of the entire area is obtained by Kriging interpolation, including the oil film thickness field h(x,y,t), latitude surface velocity field u(x,y,t), longitude surface velocity field v(x,y,t), wave height field H(x,y,t), and wave period field T(x,y,t), where t is the time dimension.

[0011] The data analysis module calculates the initial concentration field C(x,y,t0) and the marine heterogeneity adjustment coefficient α based on the continuous spatial field. het (x,y,t) is used to establish a pollution diffusion equation. The pollution concentration field C(x,y,t) at time t is expressed as:

[0012]

[0013] Where, k d Here, E is the natural decay coefficient of pollutants, and E is the horizontal diffusion coefficient.

[0014] After obtaining the pollution concentration field C(x,y,t), the data analysis module defines the real-time ecological damage rate F. r (t) and cumulative ecological damage F c (T) and continuously send it to the early warning module. The early warning module then activates the prevention and control trigger mechanism based on the comparison between the two and the preset threshold.

[0015] In any of the above technical solutions, further, when the existence of a pollution source is known within the space field, an additional pollution source term S(x,y,t) is constructed and added to the pollution diffusion equation. The calculation formula for the pollution source term S(x,y,t) is as follows:

[0016]

[0017] Where Q(t) is the emission intensity of the pollution source, x0 and y0 are the coordinates of the pollution source in the computational grid; r is the characteristic diffusion radius of the leak in space, which is equivalent to the standard deviation of the Gaussian kernel and determines the initial range of the oil released instantaneously at time t that diffuses outward on the horizontal plane.

[0018] The pollution diffusion equation with the pollution source term added is expressed as:

[0019]

[0020] In any of the above technical solutions, further, each buoy probe on the water surface is connected to an anchor on the seabed via a tow rope.

[0021] In any of the above technical solutions, taking the calculation of the oil film thickness field h(x,y,t) as an example, the calculation method of Kriging interpolation is as follows:

[0022] Collect the oil film thickness h from n buoy probes at the same time t, with coordinates (x, y, t). i ,y i The oil film thickness collected by the i-th buoy probe is h. i The film thickness field h(x,y,t) is calculated using the following formula:

[0023]

[0024] Where, ε i (x i ,y i Let be the weight value of the i-th buoy probe, which is related to (x,y) and (x...). i ,y i The distance between two points is inversely correlated.

[0025] In any of the above technical solutions, the calculation process of the initial concentration field C(x,y,t0) further includes:

[0026] Record the oil film thickness field h(x,y,t0) and the mixed layer thickness field D at time t0. m (x,y,t0), calculate the initial concentration field C(x,y,t0) using the following formula:

[0027]

[0028] Where, ρ oil The density of the oil is used to calculate the initial concentration field C(x,y,t0) to provide initial values ​​for the pollution diffusion equation.

[0029] In any of the above technical solutions, further, the marine heterogeneity adjustment coefficient α het The formula for calculating (x,y,t) is:

[0030]

[0031] Where λ is the weighting coefficient, u max v max H max and T max These are the maximum values ​​collected for latitude surface current velocity, longitude surface current velocity, wave height, and wave period, respectively.

[0032] In any of the above technical solutions, further, the real-time ecological damage rate F r The formula for calculating (t) is:

[0033]

[0034] Among them, C safe The baseline concentration for ecological security is generated from a GIS geographic database. Ω refers to the assessment area, and μ is a constant greater than 1, emphasizing the nonlinear damage of pollution to the ecosystem.

[0035] In any of the above technical solutions, further, the cumulative ecological damage F c The formula for calculating (T) is:

[0036]

[0037] Where T is the cumulative duration, T = t - t0.

[0038] In any of the above technical solutions, further, based on the real-time ecological damage rate F r (t) and cumulative ecological damage F c (T) The prevention and control triggering mechanisms established include:

[0039] The early warning module continuously monitors the real-time ecological damage rate F. r (t) and cumulative ecological damage F c (T), when F r When (t) exceeds a preset threshold, an alarm is sent to relevant personnel; when F c When (T) exceeds the preset threshold, an alarm is sounded throughout the dock, vessels are suspended from entering and leaving, the oil booms at the dock are opened, the oil pumping system is started to actively extract the pollution, and a pollution monitoring report is sent to the superior unit.

[0040] The beneficial effects of this invention are:

[0041] The technical solution in this invention uses a network of concentrically distributed buoy probes and Kriging interpolation to achieve high-precision spatial reconstruction of oil film thickness, surface flow velocity and wave parameters for the entire water area, eliminating monitoring blind spots and ensuring real-time observation around the clock.

[0042] By introducing a marine heterogeneity adjustment coefficient into the pollution diffusion equation and combining it with the dynamic changes of wind, waves and the mixing layer, the horizontal diffusion coefficient is corrected online, which significantly improves the response sensitivity to non-uniform diffusion processes and high-concentration abrupt change zones.

[0043] By flexibly adding known pollution source terms to the pollution diffusion equation, we can achieve rapid location of leak accidents and superposition simulation of concentration fields, thereby improving emergency response efficiency.

[0044] The system defines real-time ecological damage rate and cumulative ecological damage, combines pollution concentration fields with ecological safety benchmarks, and achieves spatiotemporal quantitative assessment of ecological damage, providing management departments with scientific risk assessment indicators. The early warning module can automatically trigger multi-level response measures (audible and visual alarms, opening and closing of oil booms, starting of oil pumps, etc.) based on the comparison of real-time ecological damage rate and cumulative damage with thresholds, and promptly report monitoring reports to higher-level units, realizing closed-loop management of "monitoring-assessment-early warning-response". Attached Figure Description

[0045] The advantages of the above and additional aspects of the present invention will become apparent and readily understood in the description of the embodiments in conjunction with the following drawings, wherein:

[0046] Figure 1 This is a schematic flowchart of an ecological damage assessment system based on pollution diffusion simulation according to an embodiment of the present invention. Detailed Implementation

[0047] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0048] In the following description, many specific details are set forth in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0049] like Figure 1 As shown in the figure, this embodiment provides an ecological damage assessment system based on pollution diffusion simulation. The system includes an oil spill sensor monitoring network, a data analysis module, and an early warning module.

[0050] The oil spill sensing and monitoring network consists of multiple buoy probes deployed on the water surface, with the center of the berth at the wharf as the origin. Each buoy probe is connected to an anchor on the seabed via a tow rope. The buoy probes are divided into multiple groups, each group distributed on a concentric ring with a different radius centered on the origin. In other words, the buoy probes are grouped and distributed on multiple concentric rings centered on the origin. All the buoy probes together form the oil spill sensing and monitoring network. Each buoy probe has a built-in communication device that wirelessly transmits the collected information to the data analysis module.

[0051] The buoy probe is equipped with an ultrasonic oil film thickness sensor, an ADCP Doppler current meter, and a wave sequence parameter sensor. The information collected by the buoy probe includes: oil film thickness h, latitude surface velocity u, longitude surface velocity v, wave height H, and wave period T.

[0052] The data analysis module constructs a computational grid based on the arrangement of buoy probes on the oil spill sensing network. This computational grid is divided into uniform grids along the x (latitude) and y (longitude) directions, with the monitoring area as the boundary.

[0053] Each buoy probe is mapped to a computational grid as a data point. Based on the coordinates of all data points and the data they carry, the continuous spatial field of the entire region is obtained through Kriging interpolation, including the oil film thickness field h(x,y,t), the latitude surface velocity field u(x,y,t), the longitude surface velocity field v(x,y,t), the wave height field H(x,y,t), and the wave period field T(x,y,t), where t is the time dimension.

[0054] Taking the calculation of the oil film thickness field h(x,y,t) as an example, the calculation method of Kriging interpolation is as follows:

[0055] Collect the oil film thickness h from n buoy probes at the same time t, with coordinates (x, y, t). i ,y i The oil film thickness collected by the i-th buoy probe is h. i The film thickness field h(x,y,t) is calculated using the following formula:

[0056]

[0057] Where, ε i (x i ,y i Let be the weight value of the i-th buoy probe, which is related to (x,y) and (x...). i ,y i The distance between two points is inversely correlated; the farther apart the measurement points are, the weaker their spatial correlation.

[0058] Water bodies can form a mixing layer vertically due to factors such as wind, waves, temperature, or salinity differences. Within this mixing layer, the water is thoroughly mixed due to turbulence and waves, resulting in relatively homogeneous physical and chemical properties. However, below the mixing layer, stronger stratification often occurs, making mixing difficult. The thickness field D of the mixing layer is calculated using an empirical function. m (x,y,t):

[0059] D m (x,y,t)=D0+β H H(x,y,t)+β T T(x,y,t);

[0060] Where D0 is the baseline mixed layer thickness under calm conditions, β H and β T These are the empirical incremental coefficients for the deepening of the mixing layer, namely wave height and wave period. When the waves are large or the wave period is long, the turbulent energy generated by the wind and waves is greater, and the mixing layer will be thicker.

[0061] The data analysis module performs real-time analysis on the collected data, calculating the parameters and coefficients required by the model:

[0062] Record the oil film thickness field h(x,y,t0) and the mixed layer thickness field D at time t0. m (x,y,t0), calculate the initial concentration field C(x,y,t0):

[0063]

[0064] Where, ρ oil The density of the oil is used to calculate the initial concentration field C(x,y,t0), which provides initial values ​​for the pollution diffusion equation.

[0065] Since the diffusion process in actual sea areas is non-uniform, the horizontal diffusion coefficient E, which is usually constant in a typical diffusion-convection model, cannot accurately describe the actual situation. This invention defines a marine heterogeneity adjustment coefficient α. het (x,y,t) is used to assist in describing the actual situation using the horizontal diffusion coefficient E, and the marine heterogeneity adjustment coefficient α. het The formula for calculating (x,y,t) is:

[0066]

[0067] Where λ is the weighting coefficient, u max v max H max and T max These are the maximum values ​​collected for latitude surface current velocity, longitude surface current velocity, wave height, and wave period, respectively.

[0068] Based on the above, this invention establishes the following pollution diffusion equation to calculate the pollution concentration field C(x,y,t) at time t:

[0069]

[0070] Where, k d denoted as the natural decay coefficient of pollutants, and E as the horizontal diffusion coefficient.

[0071] The finite element method is used to perform online iterations for each time step, and the time step size is automatically adjusted according to the concentration gradient to calculate the pollution concentration field C(x,y,t) at the required time t, which is then used for subsequent evaluation.

[0072] Furthermore, if a pollution source is known within the space field (e.g., a leak has occurred on a docked oil tanker), then a pollution source term S(x,y,t) is constructed and added to the pollution diffusion equation. The formula for calculating the pollution source term S(x,y,t) is as follows:

[0073]

[0074] Where Q(t) is the emission intensity of the pollution source, x0 and y0 are the coordinates of the pollution source in the computational grid, and r is the characteristic diffusion radius of the leak in space, which is equivalent to the standard deviation of the Gaussian kernel and determines the initial range of the oil released instantaneously at time t that diffuses outward on the horizontal plane.

[0075] The pollution diffusion equation with the pollution source term added is expressed as:

[0076]

[0077] Similar to the previous pollution diffusion equation, it is also used to solve the pollution concentration field C(x,y,t) at time t. When it is unclear whether there is a tanker leak, S(x,y,t) can be assumed to be 0, which is exactly the same as the previous pollution diffusion equation.

[0078] The pollution diffusion equation provided by this invention, based on the traditional convection-diffusion equation, uses a marine heterogeneity adjustment coefficient to assist the constant diffusion coefficient and adds an attenuation term k. d C(x,y,t) and pollution source term S(x,y,t) are used to improve the response sensitivity to high concentration abrupt changes and pollution peak effects.

[0079] After obtaining the pollution concentration field C(x,y,t) at time t, this invention further defines the real-time ecological damage rate F. r (t):

[0080]

[0081] Among them, C safe The baseline concentration for ecological security is generated from a GIS geographic database. Ω refers to the assessment area, and μ is a constant greater than 1, which can emphasize the nonlinear damage of pollution to the ecology.

[0082] Furthermore, the cumulative ecological damage F can be obtained by integrating the real-time ecological damage rate over time. c (T):

[0083]

[0084] Cumulative ecological damage F c (T) is used to assess the long-term cumulative impact of pollution over a period of time, where T is the cumulative duration, T = t - t0.

[0085] According to the real-time ecological damage rate F r (t) and cumulative ecological damage F c (T) Establish a prevention and control trigger mechanism:

[0086] The data analysis module continuously sends the real-time ecological damage rate F to the early warning module. r (t) and cumulative ecological damage F c (T), the early warning module constantly monitors these two values, when F r When (t) exceeds a preset threshold, an alarm is sent to relevant personnel; when F c When (T) exceeds the preset threshold, an alarm is sounded throughout the dock, vessels are suspended from entering and leaving, the oil booms at the dock are opened, the oil pumping system is started to actively extract the pollution, and a pollution monitoring report is sent to the superior unit.

[0087] In summary, this invention proposes an ecological damage assessment system based on pollution diffusion simulation, which includes an oil spill sensor monitoring network, a data analysis module, and an early warning module.

[0088] The oil spill sensing and monitoring network consists of multiple buoy probes arranged in concentric circles along the horizontal plane, with the center of the berth at the wharf as the origin. Several buoy probes together form the oil spill sensing and monitoring network. Each buoy probe has a built-in communication device that wirelessly transmits the collected information to the data analysis module.

[0089] The data analysis module constructs a computational grid based on the oil spill sensor monitoring network and maps the film thickness h, latitude surface velocity u, longitude surface velocity v, wave height H, and wave period T collected by each buoy probe to the grid nodes. The continuous spatial field of the entire area is obtained by Kriging interpolation, including the oil film thickness field h(x,y,t), latitude surface velocity field u(x,y,t), longitude surface velocity field v(x,y,t), wave height field H(x,y,t), and wave period field T(x,y,t), where t is the time dimension.

[0090] The data analysis module calculates the initial concentration field C(x,y,t0) and the marine heterogeneity adjustment coefficient α based on the continuous spatial field. het (x,y,t) is used to establish a pollution diffusion equation. The pollution concentration field C(x,y,t) at time t is expressed as:

[0091]

[0092] Where, k d denoted as the natural decay coefficient of pollutants, and E as the horizontal diffusion coefficient.

[0093] After obtaining the pollution concentration field C(x,y,t), the data analysis module defines the real-time ecological damage rate F. r (t) and cumulative ecological damage F c (T) and continuously send it to the early warning module. The early warning module then activates the prevention and control trigger mechanism based on the comparison between the two and the preset threshold.

[0094] When a pollution source is known to exist within the space field, an additional pollution source term S(x,y,t) is constructed and added to the pollution diffusion equation. The formula for calculating the pollution source term S(x,y,t) is as follows:

[0095]

[0096] Where Q(t) is the emission intensity of the pollution source, x0 and y0 are the coordinates of the pollution source in the computational grid, and r is the characteristic diffusion radius of the leak in space, which is equivalent to the standard deviation of the Gaussian kernel and determines the initial range of the oil released instantaneously at time t that diffuses outward on the horizontal plane.

[0097] The pollution diffusion equation with the pollution source term added is expressed as:

[0098]

[0099] The steps in this invention can be adjusted, combined, or deleted according to actual needs.

[0100] The units in the device of the present invention can be merged, divided, or reduced according to actual needs.

[0101] Although the invention has been disclosed in detail with reference to the accompanying drawings, it should be understood that these descriptions are merely exemplary and not intended to limit the application of the invention. The scope of protection of the invention is defined by the appended claims and may include various modifications, alterations, and equivalents made to the invention without departing from the scope and spirit of the invention.

Claims

1. An ecological damage assessment system based on pollution diffusion simulation, characterized in that, The system includes: an oil spill sensor monitoring network, a data analysis module, and an early warning module; The oil spill sensing and monitoring network consists of multiple buoy probes deployed on the water surface with the center of the berth at the wharf as the origin. Several buoy probes are grouped and distributed on multiple concentric rings with the origin as the center, forming an oil spill sensing and monitoring network. Each buoy probe has a built-in communication device to wirelessly transmit the collected information to the data analysis module. The data analysis module constructs a computational grid based on the oil spill sensor monitoring network and maps the film thickness h, latitude surface velocity u, longitude surface velocity v, wave height H, and wave period T collected by each buoy probe to the grid nodes. The continuous spatial field of the entire area is obtained by Kriging interpolation, including the oil film thickness field h(x,y,t), latitude surface velocity field u(x,y,t), longitude surface velocity field v(x,y,t), wave height field H(x,y,t), and wave period field T(x,y,t), where t is the time dimension. The data analysis module calculates the initial concentration field C(x,y,t0) and the marine heterogeneity adjustment coefficient α based on the continuous spatial field. het (x,y,t) is used to establish a pollution diffusion equation. The pollution concentration field C(x,y,t) at time t is expressed as: Where, k d Here, E is the natural decay coefficient of pollutants, and E is the horizontal diffusion coefficient. After obtaining the pollution concentration field C(x,y,t), the data analysis module defines the real-time ecological damage rate F. r (t) and cumulative ecological damage F c (T) and continuously send it to the early warning module. The early warning module then activates the prevention and control trigger mechanism based on the comparison between the two and the preset threshold.

2. The ecological damage assessment system based on pollution diffusion simulation as described in claim 1, characterized in that, When a pollution source is known to exist within the space field, an additional pollution source term S(x,y,t) is constructed and added to the pollution diffusion equation. The formula for calculating the pollution source term S(x,y,t) is as follows: Where Q(t) is the emission intensity of the pollution source, x0 and y0 are the coordinates of the pollution source in the computational grid; r is the characteristic diffusion radius of the leak in space, which is equivalent to the standard deviation of the Gaussian kernel and determines the initial range of the oil released instantaneously at time t that diffuses outward on the horizontal plane. The pollution diffusion equation with the pollution source term added is expressed as:

3. The ecological damage assessment system based on pollution diffusion simulation as described in claim 1, characterized in that, Each buoy probe on the water's surface is connected to an anchor on the seabed via a tow rope.

4. The ecological damage assessment system based on pollution diffusion simulation as described in claim 1, characterized in that, Taking the calculation of the oil film thickness field h(x,y,t) as an example, the calculation method of Kriging interpolation is as follows: Collect the oil film thickness h from n buoy probes at the same time t, with coordinates (x, y, t). i ,y i The oil film thickness collected by the i-th buoy probe is h. i The film thickness field h(x,y,t) is calculated using the following formula: Where, ε i (x i ,y i Let be the weight value of the i-th buoy probe, which is related to (x,y) and (x...). i ,y i The distance between two points is inversely correlated.

5. The ecological damage assessment system based on pollution diffusion simulation as described in claim 1, characterized in that, The calculation process of the initial concentration field C(x,y,t0) includes: Record the oil film thickness field h(x,y,t0) and the mixed layer thickness field D at time t0. m (x,y,t0), calculate the initial concentration field C(x,y,t0) using the following formula: Where, ρ oil The density of the oil is used to calculate the initial concentration field C(x,y,t0) to provide initial values ​​for the pollution diffusion equation.

6. The ecological damage assessment system based on pollution diffusion simulation as described in claim 1, characterized in that, The marine heterogeneity adjustment coefficient α het The formula for calculating (x,y,t) is: Where λ is the weighting coefficient, u max v max H max and T max These are the maximum values ​​collected for latitude surface current velocity, longitude surface current velocity, wave height, and wave period, respectively.

7. The ecological damage assessment system based on pollution diffusion simulation as described in claim 1, characterized in that, The real-time ecological damage rate F r The formula for calculating (t) is: Among them, C safe The baseline concentration for ecological security is generated from a GIS geographic database. Ω refers to the assessment area, and μ is a constant greater than 1, emphasizing the nonlinear damage of pollution to the ecosystem.

8. The ecological damage assessment system based on pollution diffusion simulation as described in claim 7, characterized in that, The cumulative ecological damage F c The formula for calculating (T) is: Where T is the cumulative duration, T = t - t0.

9. The ecological damage assessment system based on pollution diffusion simulation as described in any one of claims 7 or 8, characterized in that, According to the real-time ecological damage rate F r (t) and cumulative ecological damage F c (T) The prevention and control triggering mechanisms established include: The early warning module continuously monitors the real-time ecological damage rate F. r (t) and cumulative ecological damage F c (T), when F r When (t) exceeds a preset threshold, an alarm is sent to relevant personnel; when F c When (T) exceeds the preset threshold, an alarm is sounded throughout the dock, vessels are suspended from entering and leaving, the oil booms at the dock are opened, the oil pumping system is started to actively extract the pollution, and a pollution monitoring report is sent to the superior unit.

Images