A water turbidity measurement method and system for water ecological investigation

Abstract

The application provides a water turbidity measurement method and system for water ecological investigation, which determines the scattering difference characteristics of light rays by suspended particles in the water to be measured by collecting the scattering light signal of the water to be measured and the light signal of the corresponding environmental background of the water to be measured, determines the disturbance error of the flow rate in the water to be measured when measuring the suspended particles, determines the turbidity gradient of the suspended particles in the water to be measured based on a turbidity inversion model combined with the scattering difference characteristics and the disturbance error, determines the viscosity state of the water power in the water to be measured, determines the attenuation relationship between the suspended particles and the temperature in the water to be measured according to the viscosity state and the fluctuation characteristics of the ambient temperature of the water to be measured, dynamically compensates the turbidity gradient of the suspended particles in the water to be measured through the attenuation relationship, and further obtains the dynamic turbidity value of the water to be measured. The application can reduce the influence of the measurement of the water turbidity in the water to be measured under the dynamic interference of multiple parameters.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of water turbidity measurement, and more particularly to a water turbidity measurement method and system for water ecological investigation. BACKGROUND

[0002] Water turbidity is an important water quality index for measuring the scattering and absorption ability of suspended particles (such as silt, algae, organic matter, etc.) in water, and its measurement aims to quantify water transparency and pollution level, and to provide key data support for water ecological monitoring, water source protection, sewage treatment, etc. Common measurement methods include visual turbidity method, spectrophotometry, and turbidimeter method (such as scattered light type turbidimeter).

[0003] In water ecological investigation, water turbidity, as an important parameter representing the health status of water ecological system, is a key indicator for water quality monitoring and hydrological research. Traditional turbidity measurement methods are mostly based on fixed-angle scattered light detection or transmitted light attenuation principle, and the turbidity value is calculated by capturing the scattering or absorption signal of suspended particles on light through photoelectric sensor. However, the natural water environment has dynamic complexity, and the existing technology has significant limitations. First, the periodic change of environmental background light (such as sunlight angle shift and water surface reflection fluctuation) will form superimposed interference with the target scattering signal, making it difficult for conventional single light source measurement system to effectively separate the effective signal. Second, the non-uniform distribution of suspended particles in flowing water is affected by flow velocity, and the traditional static model cannot correct the turbidity gradient distortion caused by particle drift. Third, the temperature sensitivity of water viscosity will cause the change of suspended particle settling rate, and the existing method lacks a dynamic compensation mechanism for temperature-viscosity coupling effect, especially in open water areas with significant day-night temperature difference, long-term monitoring data is prone to systematic bias. Therefore, how to reduce the influence of measuring water turbidity in the measured water under the dynamic interference of multiple parameters has become a problem in the industry. SUMMARY

[0004] The present application provides a water turbidity measurement method and system for water ecological investigation, which can reduce the influence of measuring water turbidity in the measured water under the dynamic interference of multiple parameters.

[0005] In a first aspect, the present application provides a water turbidity measurement method for water ecological investigation, comprising the following steps:

[0006] Alternately irradiating the measured water, and collecting the scattered light signal of the measured water;

[0007] Synchronously fitting the scattered light signal and the light signal of the corresponding environmental background of the measured water to obtain the scattering difference characteristics of the suspended particles in the measured water on light, and determining the disturbance error of the flow velocity in the measured water on measuring the suspended particles;

[0008] construct a turbidity inversion model of the to-be-measured water area, and perform turbidity inversion on the suspended particles in the to-be-measured water body based on the turbidity inversion model in combination with the scattering difference feature and the disturbance error, to obtain a turbidity gradient of the suspended particles in the to-be-measured water body;

[0009] determine a viscosity state of a water body power in the to-be-measured water body, and determine an attenuation relationship between the suspended particles and temperature in the to-be-measured water body according to the viscosity state and fluctuation characteristics of ambient temperature of the to-be-measured water body;

[0010] dynamically compensate the turbidity gradient of the suspended particles in the to-be-measured water body through the attenuation relationship, and further obtain a dynamic turbidity value of the to-be-measured water body.

[0011] In some embodiments, the scattering light signal and the light signal of the corresponding environmental background of the to-be-measured water body are synchronously fitted to obtain the scattering difference feature of the suspended particles in the to-be-measured water body, which specifically includes:

[0012] The light signal of the corresponding environmental background of the to-be-measured water body is collected.

[0013] The scattering light signal and the light signal of the environmental background are preprocessed to obtain a preprocessed scattering light signal and a preprocessed light signal of the environmental background.

[0014] The preprocessed scattering light signal and the preprocessed light signal of the environmental background are time series aligned to obtain a time series signal data set.

[0015] The scattering difference feature of the suspended particles in the to-be-measured water body is extracted from the time series signal data set.

[0016] In some embodiments, determining the disturbance error of the flow velocity on the measurement of the suspended particles in the to-be-measured water body specifically includes:

[0017] The three-dimensional flow velocity distribution of the to-be-measured water body is obtained.

[0018] The horizontal loss and the vertical loss of the flow velocity on the suspended particles in the to-be-measured water body are determined according to the three-dimensional flow velocity distribution.

[0019] The disturbance error of the flow velocity on the measurement of the suspended particles in the to-be-measured water body is determined through the horizontal loss and the vertical loss.

[0020] In some embodiments, the turbidity inversion on the suspended particles in the to-be-measured water body based on the turbidity inversion model in combination with the scattering difference feature and the disturbance error to obtain the turbidity gradient of the suspended particles in the to-be-measured water body specifically includes:

[0021] The scattering difference feature is normalized to obtain a standardized scattering difference feature.

[0022] determine a turbidity gradient of the suspended particles in the water body to be measured based on the turbidity inversion model combined with the normalized scattering difference feature and the perturbation error.

[0023] In some embodiments, determining the viscosity state of the water body dynamics in the water body to be measured specifically comprises:

[0024] monitoring temperature, salinity and pressure data at different depths in the water body to be measured;

[0025] determining the viscosity state of the water body dynamics in the water body to be measured according to the temperature, salinity and pressure data at different depths.

[0026] In some embodiments, determining the attenuation relationship between the suspended particles and temperature in the water body to be measured according to the viscosity state and fluctuation feature of ambient temperature around the water body to be measured specifically comprises:

[0027] determining the fluctuation feature of ambient temperature around the water body to be measured;

[0028] correlation analysis of the viscosity state and the fluctuation feature of ambient temperature, to obtain a correlation feature between temperature and viscosity;

[0029] determining the attenuation relationship between the suspended particles and temperature in the water body to be measured according to the correlation feature.

[0030] In some embodiments, dynamically compensating the turbidity gradient of the suspended particles in the water body to be measured through the attenuation relationship, to obtain a dynamic turbidity value of the water body to be measured specifically comprises:

[0031] dynamically compensating the turbidity gradient of the suspended particles in the water body to be measured according to the attenuation relationship, to obtain a compensated turbidity gradient;

[0032] determining the dynamic turbidity value of the water body to be measured through the compensated turbidity gradient.

[0033] In some embodiments, a photodetector is used to collect the scattered light signal of the water body to be measured.

[0034] In some embodiments, a machine learning algorithm is used to construct the turbidity inversion model of the water body to be measured.

[0035] In a second aspect, the present application provides a water body turbidity measurement system for water ecological investigation, comprising:

[0036] a collection module for alternately irradiating the water body to be measured and collecting the scattered light signal of the water body to be measured;

[0037] The processing module is configured to perform synchronous fitting on the scattered light signal and a light signal corresponding to an environmental background of the water body to be measured, to obtain a scattering difference feature of the suspended particles in the water body to be measured with respect to light, and to determine a disturbance error of a flow velocity in the water body to be measured on measurement of the suspended particles.

[0038] The processing module is further configured to construct a turbidity inversion model of the water area to be measured, and perform turbidity inversion on the suspended particles in the water body to be measured based on the turbidity inversion model in combination with the scattering difference feature and the disturbance error, to obtain a turbidity gradient of the suspended particles in the water body to be measured.

[0039] The processing module is further configured to determine a viscosity state of a water body power in the water body to be measured, and determine an attenuation relationship between the suspended particles and temperature in the water body to be measured according to the viscosity state and fluctuation characteristics of ambient temperature of the water body to be measured.

[0040] The execution module is configured to perform dynamic compensation on the turbidity gradient of the suspended particles in the water body to be measured through the attenuation relationship, to further obtain a dynamic turbidity value of the water body to be measured.

[0041] The technical scheme provided by the embodiments disclosed in the present application has the following beneficial effects:

[0042] In the water body turbidity measurement method and device for water ecological investigation provided in the present application, the water body to be measured is first irradiated alternately, and a scattered light signal of the water body to be measured is collected. The scattered light signal and a light signal corresponding to an environmental background of the water body to be measured are synchronously fitted to obtain a scattering difference feature of the suspended particles in the water body to be measured with respect to light, and a disturbance error of a flow velocity in the water body to be measured on measurement of the suspended particles is determined. A turbidity inversion model of the water area to be measured is constructed, and turbidity inversion is performed on the suspended particles in the water body to be measured based on the turbidity inversion model in combination with the scattering difference feature and the disturbance error, to obtain a turbidity gradient of the suspended particles in the water body to be measured. A viscosity state of a water body power in the water body to be measured is determined, and an attenuation relationship between the suspended particles and temperature in the water body to be measured is determined according to the viscosity state and fluctuation characteristics of ambient temperature of the water body to be measured. Dynamic compensation is performed on the turbidity gradient of the suspended particles in the water body to be measured through the attenuation relationship, to further obtain a dynamic turbidity value of the water body to be measured.

[0043] It can be seen that, in the process of measuring the turbidity of the water body, first, the disturbance of ambient light (such as sunlight, instrument thermal noise) to the scattering signal can be eliminated by synchronous fitting of the scattering light signal and the background light signal, and the scattering signal fluctuation caused by the flow rate (such as Doppler effect or turbulent disturbance) can be separated by difference feature extraction, the dynamic error of the flow rate on the turbidity measurement is quantified, and the basis for subsequent error compensation is provided; secondly, based on the turbidity inversion model, the scattering difference feature and the flow rate disturbance error are fused, the turbidity measurement deviation caused by uneven particle distribution or flow rate change can be dynamically corrected, the inversion of the turbidity gradient can represent the spatial variation of the particle concentration, and the spatial resolution and accuracy of the turbidity measurement under complex hydrodynamic conditions can be improved; then, the influence of the water flow resistance on the particle sedimentation is analyzed through the viscosity state, the temperature fluctuation characteristics (such as thermal expansion, enhanced Brownian motion) are combined, a temperature-turbidity attenuation model is established, the particle scattering characteristic drift (such as particle size change or agglomeration effect) caused by temperature change can be compensated, and the indirect interference of thermodynamic parameters on the turbidity is reduced; finally, the dynamic turbidity value is obtained by dynamically compensating the turbidity gradient through the attenuation relationship, the dynamic compensation mechanism can correct the influence of temperature, viscosity and other multi-parameter coupling on the turbidity (such as slow particle sedimentation caused by low temperature and high viscosity in winter), and finally output stable and anti-interference dynamic turbidity value, which significantly improves the measurement robustness in multi-parameter interference environment. By using the above scheme, the influence of multi-parameter dynamic interference on the measurement of the turbidity of the water body to be measured in the water body can be reduced. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 is an example flow chart of a method for measuring the turbidity of a water body for water ecological investigation according to some embodiments of the present application;

[0045] Figure 2 is an example diagram of alternate irradiation according to some embodiments of the present application;

[0046] Figure 3 is an example flow chart of determining disturbance error according to some embodiments of the present application;

[0047] Figure 4 is a structural schematic diagram of a water body turbidity measurement system for water ecological investigation according to some embodiments of the present application;

[0048] Figure 5 is a structural schematic diagram of a computer device for implementing a method for measuring the turbidity of a water body for water ecological investigation according to some embodiments of the present application. DETAILED DESCRIPTION

[0049] In order to better understand the technical solutions of the present application, the technical solutions of the present application will be described in detail below in combination with the drawings in the specification and specific embodiments.

[0050] ReferenceFigure 1 , which is an exemplary flow chart of a water turbidity measurement method for water ecological survey according to some embodiments of the present application. The water turbidity measurement method 100 for water ecological survey mainly includes the following steps:

[0051] In step 101, a water body to be measured is alternately illuminated, and scattered light signals of the water body to be measured are collected.

[0052] In specific implementation, first, a dual light source system is used as an alternating irradiation device. Two light sources of different wavelengths (such as green light and infrared light) are used under the action of a controller to emit light to the water body to be tested at preset time intervals (for example, 1 second of green light irradiation and 1 second of infrared light irradiation alternately); then, a high-sensitivity photodetector (such as an avalanche photodiode) is installed at a certain distance from the light source at a specific angle (such as a 90-degree scattering angle, which is a commonly used angle for water turbidity measurement and can effectively collect scattered light signals) to capture the light signal generated by the suspended particles in the water body to be tested. Finally, the light signal collected by the photodetector is used as the scattered light signal of the water body to be tested; in other embodiments, other methods of collection can also be used, which are not limited here.

[0053] It should be noted that the scattered light signal in the present application represents the signal when light is scattered in the water body to be measured, which can be used to analyze the concentration, particle size distribution and optical properties of suspended particles in the water body.

[0054] In some embodiments, reference Figure 2 As shown, this figure is an example of alternating illumination in some embodiments of the present application, such as Figure 2 As described above, the water body to be tested is alternately illuminated by two light sources of different wavelengths (such as green light and infrared light), and the scattered light signal is collected by the collection device.

[0055] In step 102, the scattered light signal and the light signal of the environmental background corresponding to the water body to be measured are synchronously fitted to obtain the scattering difference characteristics of suspended particles in the water body to be measured, and determine the disturbance error of the flow velocity in the water body to measure the suspended particles.

[0056] In some embodiments, synchronously fitting the scattered light signal and the light signal of the environmental background corresponding to the water body to be tested to obtain the scattering difference characteristics of the suspended particles in the water body to be tested can be achieved by the following steps:

[0057] Collecting the light signal of the environmental background corresponding to the water body to be measured;

[0058] Preprocessing the scattered light signal and the light signal of the environmental background to obtain a preprocessed scattered light signal and a preprocessed light signal of the environmental background;

[0059] Performing time series alignment on the preprocessed scattered light signal and the preprocessed ambient background light signal to obtain a time series signal data set;

[0060] The light scattering difference characteristics of suspended particles in the water body to be tested are extracted from the time series signal data set.

[0061] In the specific implementation, first, before the irradiation device irradiates the water body to be tested, the light signal of the environmental background is collected by using the same photoelectric detector as that for collecting the scattered light signal, thereby reducing the interference of the ambient stray light. Then, the scattered light signal and the light signal of the environmental background are preprocessed, namely: the median filtering algorithm is first used to remove the salt and pepper noise in the scattered light signal and the light signal of the environmental background, and then the wavelet denoising algorithm is used to decompose the scattered light signal and the light signal of the environmental background into different frequency layers, and the high-frequency noise in the scattered light signal and the light signal of the environmental background is eliminated by threshold processing, thereby obtaining the preprocessed scattered light signal and the light signal of the preprocessed environmental background. Then, the interpolation alignment method based on the timestamp is used to align the preprocessed scattered light signal and the preprocessed environmental background. The light signals of the scene are aligned in time series, and the aligned data set is used as the time series signal data set. If the sampling frequencies of the two signals are different, the low-frequency signal is resampled to the sampling frequency of the high-frequency signal using the cubic spline interpolation algorithm, so that the time points of the two types of signals are completely corresponding. Finally, the time series signal data set is curve fitted using the least squares method to establish a mathematical relationship model (such as a linear model or a nonlinear model) between the scattered light signal and the ambient background light signal. The difference in the scattered light intensity relative to the background light intensity at different wavelengths and the signal change slope are extracted from the mathematical relationship model, and all the differences and signal change slopes are used as the scattering difference characteristics of suspended particles in the water body to be tested to light. In other embodiments, other methods can also be used for determination, which are not limited here.

[0062] It should be noted that the scattering difference characteristics in this application represent the difference characteristics of the scattering effect of suspended particles in the water body to be tested on light relative to the ambient background light signal, which can be used to analyze the interference of background light, thereby reducing the impact of background light on the detection of suspended particles in the water body to be tested.

[0063] In some embodiments, reference Figure 3 As shown in FIG. 1 , this figure is an exemplary flow chart for determining disturbance errors in some embodiments of the present application. In this embodiment, determining the disturbance error of the flow velocity in the measured water body on the measurement of suspended particles can be achieved by using the following steps:

[0064] First, in step 1021, the three-dimensional flow velocity distribution of the water body to be measured is obtained;

[0065] Secondly, in step 1022, the horizontal loss and the vertical loss of the suspended particles in the water body to be measured are determined according to the three-dimensional flow velocity distribution;

[0066] Finally, in step 1023, the disturbance error of the suspended particles in the water body to be measured is determined by the horizontal loss and the vertical loss.

[0067] In a specific implementation, firstly, the three-dimensional flow velocity distribution of the water body to be measured can be acquired in the following manner: a multi-point measurement is performed at different positions and depths of the water body to be measured by using an acoustic Doppler current profiler, so as to acquire flow velocity components of the water body in a three-dimensional space (x, y, z directions), and then a three-dimensional flow velocity distribution of the water body to be measured is constructed, wherein the three-dimensional flow velocity distribution represents a flow velocity distribution of the three-dimensional space in the water body to be measured, if the measurement region is large, continuous measurement can be performed in combination with a walk-through acoustic Doppler current profiler, and a Kriging interpolation method is used to perform spatial interpolation on the discrete measurement data, so as to obtain a continuous and smooth three-dimensional flow velocity distribution; in other embodiments, other manners can be used to acquire the three-dimensional flow velocity distribution, which is not limited here.

[0068] In a specific implementation, the horizontal loss and the vertical loss of the suspended particles in the water body to be measured can be determined according to the three-dimensional flow velocity distribution in the following manner: in calculating the horizontal loss, the horizontal motion track of the suspended particles along with the water flow is tracked in the horizontal direction by using a Lagrangian particle tracking method, considering the advection effect of the water flow, the loss amount in the horizontal direction is determined by counting the number or mass of the particles that move out of the measurement region due to the advection effect of the water flow in a unit time, and the loss amount in the horizontal direction is taken as the horizontal loss of the suspended particles in the water body to be measured, wherein the horizontal loss represents a parameter value of the loss degree of the suspended particles in the horizontal direction in the water body to be measured; in calculating the vertical loss, the loss amount caused by the vertical motion of the water flow and the sedimentation of the particles is solved by establishing a motion equation of the particles in the vertical direction, considering the sedimentation velocity of the particles and the vertical flow velocity component of the water flow in combination with Stokes' law, and the loss amount caused by the vertical motion of the water flow and the sedimentation of the particles is taken as the vertical loss of the suspended particles in the water body to be measured, wherein the vertical loss represents a parameter value of the loss degree of the suspended particles in the vertical direction in the water body to be measured; in other embodiments, other manners can be used to determine the horizontal loss and the vertical loss, which is not limited here.

[0069] In a specific implementation, the disturbance error of the suspended particles in the water body to be measured is determined by the horizontal loss and the vertical loss in the following manner: the horizontal loss and the vertical loss are vector-synthesized (for example, in a manner of squaring and square-rooting), and the loss obtained by the vector synthesis is taken as the disturbance error of the suspended particles in the water body to be measured; in other embodiments, other manners can be used to determine the disturbance error, which is not limited here.

[0070] It should be noted that the disturbance error in the present application represents the error when the flow velocity in the water body to be measured interferes with the suspended particles, and can be used to analyze the state of the suspended particles in the water body to be measured, thereby reducing the influence of the flow velocity on the detection of the suspended particles.

[0071] In step 103, a turbidity inversion model of the water area to be measured is constructed, and the turbidity of the suspended particles in the water body to be measured is inversed based on the turbidity inversion model combined with the scattering difference feature and the disturbance error, to obtain the turbidity gradient of the suspended particles in the water body to be measured.

[0072] In a specific implementation, the turbidity inversion model of the water area to be measured can be implemented in the following manner: when constructing the turbidity inversion model, a machine learning algorithm (such as random forest or neural network) can be used to learn the nonlinear mapping relationship among the historically measured scattering difference feature, disturbance error data, and actual turbidity value as a training set, through model training and optimization of parameters, to take the disturbance error as a correction factor, the scattering difference feature as a core variable, establish a fitting equation, and take the fitting equation as the turbidity inversion model between the disturbance error, the scattering difference feature, and the water turbidity, wherein the turbidity inversion model is an algorithm model established based on the quantitative relationship between the light signal (such as scattered light, transmitted light, and reflected light) and the water turbidity, and can be used to predict the water turbidity in the water body to be measured. In other embodiments, other ways can also be used for construction, which are not limited here.

[0073] In some embodiments, the turbidity of the suspended particles in the water body to be measured can be inversed based on the turbidity inversion model combined with the scattering difference feature and the disturbance error, to obtain the turbidity gradient of the suspended particles in the water body to be measured, which can be implemented in the following steps:

[0074] The scattering difference feature is normalized to obtain a standardized scattering difference feature;

[0075] The turbidity gradient of the suspended particles in the water body to be measured is determined based on the turbidity inversion model combined with the standardized scattering difference feature and the disturbance error.

[0076] It should be noted that the scattering difference feature is essentially an external manifestation of the optical properties of the particles, and the disturbance error is an external manifestation of the kinetic properties of the particles, both of which are determined by the intrinsic characteristics (concentration, particle size, and density) of the particles, and therefore there is an intrinsic physical connection. Turbidity, as a comprehensive representation of particle concentration, not only reflects the optical scattering ability (the higher the concentration, the stronger the scattering), but also is affected by the water flow transport (the faster the flow velocity, the more uneven the particle distribution), and therefore the turbidity gradient of the suspended particles in the water body to be measured can be constructed according to the scattering difference feature and the disturbance error.

[0077] In a specific implementation, the scattering difference feature is normalized to obtain a normalized scattering difference feature, that is, the scattering difference feature is normalized by using a min-max normalization algorithm to linearly map the original scattering difference feature data to the interval [0, 1], and the result after normalization is taken as the normalized scattering difference feature, so as to eliminate the differences in dimension and order of magnitude of different measurement point data, and obtain the normalized scattering difference feature. In other embodiments, other methods can also be used to determine.

[0078] In a specific implementation, the turbidity gradient of the suspended particles in the water body to be measured can be determined based on the turbidity inversion model, the normalized scattering difference feature, and the disturbance error by using the following method, that is, the entire water body to be measured is divided into a plurality of grid units by using an interactive division based on a geographic information system (such as a square or hexagonal grid), the normalized scattering difference feature and the calculated disturbance error data are taken as input parameters to input into the constructed turbidity inversion model, the turbidity value of each grid unit is calculated by the turbidity inversion model, the spatial interpolation processing is performed on the discrete turbidity values by using a Kriging interpolation method, a continuous turbidity distribution surface is generated, the turbidity variation rate of each point on the turbidity distribution surface is calculated by using a spatial derivative, and thus all the turbidity variation rates are taken as the turbidity gradient of the suspended particles in the water body to be measured. In other embodiments, other methods can also be used to determine, which are not limited here.

[0079] It should be noted that the turbidity gradient in the present application represents the gradient of the turbidity variation of the suspended particles in the water body to be measured, and can be used to intuitively present the variation trend of the turbidity in space, so as to facilitate the analysis of the turbidity in the water body to be measured.

[0080] In step 104, the viscosity state of the water body dynamics in the water body to be measured is determined, and the attenuation relationship between the suspended particles and the temperature in the water body to be measured is determined according to the viscosity state and the fluctuation characteristics of the ambient temperature of the water body to be measured.

[0081] In some embodiments, the viscosity state of the water body dynamics in the water body to be measured can be determined by using the following steps:

[0082] The temperature, salinity, and pressure data at different depths in the water body to be measured are monitored.

[0083] The viscosity state of the water body dynamics in the water body to be measured is determined according to the temperature, salinity, and pressure data at different depths.

[0084] In a specific implementation, first, the temperature, salinity and pressure data of the water body at different depths can be measured using a high-precision CTD, and then the measured data can be substituted into an empirical formula (such as an international seawater equation) to calculate the theoretical value of the dynamic viscosity of the water body at each measurement point, and all the theoretical values of the dynamic viscosity are used as the viscosity state of the water body in the water body to be measured. In other embodiments, other methods can also be used to determine the viscosity state, which is not limited here.

[0085] It should be noted that the viscosity state in this application represents the state of the viscosity degree of the water body in the water body to be measured, including the viscosity values at different depths and different regions, which can be used to analyze the turbidity of the water body.

[0086] In some embodiments, determining the attenuation relationship between the suspended particles and the temperature in the water body to be measured according to the viscosity state and the fluctuation characteristics of the ambient temperature of the water body to be measured can be achieved by the following steps:

[0087] Determine the fluctuation characteristics of the ambient temperature of the water body to be measured.

[0088] Correlation analysis is performed on the viscosity state and the fluctuation characteristics of the ambient temperature to obtain the correlation characteristics between the temperature and the viscosity.

[0089] According to the correlation characteristics, the attenuation relationship between the suspended particles and the temperature in the water body to be measured is determined.

[0090] It should be noted that temperature fluctuations can change the dynamic viscosity of the water body through the viscosity-temperature effect, and the viscosity directly affects the fluid resistance of the suspended particles. When the ambient temperature rises, the viscosity of the water body decreases, the resistance of the particles during the settling or diffusion process decreases, which leads to an increase in the movement rate of the particles, thereby accelerating the migration (attenuation) of the particles from the water body. Conversely, when the temperature decreases, the viscosity increases, the movement of the particles is hindered, and the attenuation rate slows down. Therefore, the attenuation relationship between the suspended particles and the temperature in the water body to be measured can be determined by the viscosity state and the fluctuation characteristics of the ambient temperature of the water body to be measured.

[0091] In a specific implementation, the fluctuation characteristics of the ambient temperature of the water body to be measured can be determined by the following method: using a high-precision temperature sensor (such as a platinum resistance temperature sensor) to collect the ambient temperature of the water body to be measured at a high frequency (such as 1 time per second) to obtain a time series of temperature values of the ambient temperature of the water body to be measured, converting the time series of temperature values into frequency domain data by fast Fourier transform, calculating the amplitude and range of temperature fluctuations in the frequency domain data, and using the amplitude and range of temperature fluctuations as the fluctuation characteristics of the ambient temperature of the water body to be measured, wherein the fluctuation characteristics represent the fluctuation degree of the ambient temperature of the water body to be measured. In other embodiments, other methods can also be used to determine the viscosity state, which is not limited here.

[0092] In a specific implementation, the correlation between the temperature and the viscosity can be obtained by correlating the viscosity state and the fluctuation characteristics of the ambient temperature, which can be achieved in the following way: a theoretical model of the relationship between the fluid viscosity and the temperature is constructed based on the Andrade equation, the fluctuation characteristics of the ambient temperature are taken as the independent variable, and the viscosity state is taken as the dependent variable, so as to output the change amount of the viscosity when the temperature changes by a unit value through the theoretical model, and the change amount of the viscosity when the temperature changes by a unit value is taken as the correlation between the temperature and the viscosity, wherein the correlation represents the correlation degree between the temperature and the viscosity.

[0093] In a specific implementation, the attenuation relationship between the suspended particles and the temperature in the water body to be measured can be determined according to the correlation, which can be achieved in the following way: the influence of the viscosity change on the movement resistance of the suspended particles is analyzed by using the Stokes law to establish a functional relationship between the particle movement speed and the viscosity, when the viscosity changes due to the temperature change, the change amount of the particle movement speed is calculated through the functional relationship, and the change amount is combined with the particle dynamics theory to quantify the attenuation degree of the suspended particles in the process of coagulation and sedimentation caused by the temperature change, and the attenuation degree is taken as the attenuation relationship of the suspended particles in the water body, for example, the attenuation relationship of the suspended particles caused by the temperature- viscosity change in a unit of time or the decline amplitude of the effective concentration of the particles is calculated, and finally the attenuation relationship of the temperature on the suspended particles is determined; in other embodiments, other ways can also be used to determine, which is not limited here.

[0094] It should be noted that the attenuation relationship in the present application represents the relationship of the attenuation degree of the suspended particles in the water body to be measured caused by the temperature change, such as the attenuation degree of the suspended particles in the process of coagulation and sedimentation caused by the temperature change, which can be used to analyze the suspended particles in the water body to be measured, so as to reduce the influence of the temperature on the measurement of the turbidity of the water body to be measured.

[0095] In step 105, the turbidity gradient of the suspended particles in the water body to be measured is dynamically compensated through the attenuation relationship, and then the dynamic turbidity value of the water body to be measured is obtained.

[0096] In some embodiments, the turbidity gradient of the suspended particles in the water body to be measured is dynamically compensated through the attenuation relationship, and then the dynamic turbidity value of the water body to be measured can be achieved in the following steps:

[0097] The turbidity gradient of the suspended particles in the water body to be measured is dynamically compensated according to the attenuation relationship, and a compensated turbidity gradient is obtained.

[0098] The dynamic turbidity value of the water body to be measured is determined through the compensated turbidity gradient.

[0099] It should be noted that the dynamic compensation refers to a process of correcting the original turbidity gradient measurement value by a mathematical model or algorithm on the basis of considering the time or space variation of the attenuation relationship related to the suspended particles in the water body to be measured (such as the influence of temperature, viscosity environmental factors on the optical properties or motion state of the suspended particles), so as to eliminate or weaken the interference of environmental factors, thereby obtaining a dynamic turbidity value which more accurately reflects the real turbidity state of the water body.

[0100] In a specific implementation, the turbidity gradient of the suspended particles in the water body to be measured is dynamically compensated according to the attenuation relationship, and the compensated turbidity gradient can be obtained in the following manner: the attenuation relationship is matched with the turbidity gradient of the water body to be measured based on a spatial interpolation method of a geographic information system, for each turbidity in the turbidity gradient of the water body to be measured, the turbidity is multiplied by a compensation coefficient (compensation coefficient = 1-attenuation relationship), so as to dynamically compensate the turbidity gradient, thereby obtaining the compensated turbidity gradient, which reflects the compensated turbidity gradient under the influence of temperature and can intuitively reflect the reducing effect of the attenuation relationship on the turbidity. The dynamic turbidity value of the water body to be measured can be determined by the compensated turbidity gradient in the following manner: the compensated turbidity values in the compensated turbidity gradient can be weighted and summed by using an area-weighted average method, and the value obtained by the weighted summation is taken as the dynamic turbidity value of the water body to be measured. In other embodiments, the dynamic turbidity value can be determined by using other manners, which are not limited here.

[0101] It should be noted that the dynamic turbidity value in the present application represents the turbidity value obtained after the turbidity value in the water body to be measured is dynamically compensated, which can be used to predict the turbidity value in the water body to be measured.

[0102] In addition, another aspect of the present application, in some embodiments, the present application provides a water turbidity measurement system for water ecological investigation, referring to Figure 4 The figure is a structural schematic diagram of a water turbidity measurement system for water ecological investigation according to some embodiments of the present application, which comprises a collection module 401, a processing module 402 and an execution module 403, which are described as follows:

[0103] The collection module 401 is mainly used for alternately irradiating the water body to be measured and collecting the scattered light signal of the water body to be measured in the present application.

[0104] The processing module 402 is used for synchronously fitting the scattered light signal and the light signal of the corresponding environmental background of the water body to be measured in the present application, obtaining the scattering difference characteristics of the light by the suspended particles in the water body to be measured, and determining the disturbance error of the flow velocity in the water body to be measured on the measurement of the suspended particles.

[0105] It should be noted that the processing module 402 in the present application is also used to construct a turbidity inversion model for the water body to be measured, and perform turbidity inversion on the suspended particles in the water body to be measured based on the turbidity inversion model combined with the scattering difference characteristics and the disturbance error to obtain the turbidity gradient of the suspended particles in the water body to be measured;

[0106] In addition, it should be noted that the processing module 402 in the present application is also used to determine the viscosity state of the water body dynamics in the water body to be tested, and determine the attenuation relationship between the suspended particles in the water body to be tested and the temperature based on the viscosity state and the fluctuation characteristics of the ambient temperature of the water body to be tested;

[0107] The execution module 403 in this application is mainly used to dynamically compensate the turbidity gradient of the suspended particles in the water body to be measured through the attenuation relationship, and then obtain the dynamic turbidity value of the water body to be measured.

[0108] In addition, the present application also provides a computer device, which includes a memory and a processor, wherein the memory stores code, and the processor is configured to obtain the code and execute the above-mentioned water turbidity measurement method for water ecological survey.

[0109] In some embodiments, reference Figure 5 , which is a schematic diagram of the structure of a computer device for implementing a water turbidity measurement method for water ecological survey according to some embodiments of the present application. The water turbidity measurement method for water ecological survey in the above embodiment can be Figure 5 The computer device 500 shown in FIG. 5 is implemented as shown in FIG. 5 . The computer device 500 includes at least one processor 501 , a communication bus 502 , a memory 503 , and at least one communication interface 504 .

[0110] The processor 501 may be a general-purpose central processing unit (CPU) or an application-specific integrated circuit (ASIC).

[0111] The communication bus 502 may be used to transmit information between the aforementioned components.

[0112] The memory 503 can be a read-only memory (ROM) or other type of static storage device that can store static information and instructions, a random access memory (RAM), or other type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disk storage, a magnetic disk storage or other magnetic storage devices, or any other medium capable of storing desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited to this. The memory 503 can exist independently, and is connected to the processor 501 through the communication bus 502. The memory 503 can also be integrated with the processor 501.

[0113] The memory 503 is configured to store program codes for implementing the solutions of the present application, and the processor 501 is configured to control the execution of the program codes. The processor 501 is configured to execute the program codes stored in the memory 503. The program codes can include one or more software modules. The methods used in the above embodiments can be implemented by the processor 501 and one or more software modules in the program codes in the memory 503.

[0114] The communication interface 504 is configured to communicate with other devices or communication networks, such as an Ethernet, a radio access network (RAN), a wireless local area network (WLAN), etc., using any transceiver-like device.

[0115] In specific implementations, as an example, the computer device can include multiple processors, each of which can be a single-CPU processor or a multi-CPU processor. The processor herein can refer to one or more devices, circuits, and / or processing cores for processing data (e.g., computer program instructions).

[0116] The computer device described above can be a general-purpose computer device or a special-purpose computer device. In a specific implementation, the computer device can be a desktop computer, a laptop computer, a network server, a personal digital assistant (PDA), a mobile phone, a tablet computer, a wireless terminal device, a communication device, or an embedded device. The embodiments of the present application do not limit the type of the computer device.

[0117] In addition, the present application also provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the water turbidity measurement method for water ecological investigation.

[0118] Although the preferred embodiments of the present application have been described, those skilled in the art who are familiar with the basic inventive concept can make additional changes and modifications to the embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0119] Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application also intends to include these modifications and variations.

Claims

1. A method for measuring water turbidity for water ecological survey, characterized in that: The steps include: Alternately irradiating a water body to be measured and collecting scattered light signals of the water body to be measured; Synchronously fitting the scattered light signal and the light signal of the environmental background corresponding to the water body to be measured to obtain the scattering difference characteristics of the suspended particles in the water body to be measured, and determining the disturbance error of the flow velocity in the water body to be measured on the suspended particles; Constructing a turbidity inversion model for the water body to be tested, and performing turbidity inversion on the suspended particles in the water body to be tested based on the turbidity inversion model in combination with the scattering difference characteristics and the disturbance error to obtain a turbidity gradient of the suspended particles in the water body to be tested; Determining the viscosity state of the water body dynamics in the water body to be measured, and determining the attenuation relationship between suspended particles and temperature in the water body to be measured based on the viscosity state and the fluctuation characteristics of the ambient temperature of the water body to be measured; Dynamically compensating the turbidity gradient of suspended particles in the water body to be measured by using the attenuation relationship, thereby obtaining a dynamic turbidity value of the water body to be measured; Wherein, determining the attenuation relationship between suspended particles and temperature in the water body to be measured according to the viscosity state and the fluctuation characteristics of the ambient temperature of the water body to be measured specifically includes: Determining the fluctuation characteristics of the ambient temperature of the water body to be measured; performing correlation analysis on the viscosity state and the fluctuation characteristics of the ambient temperature to obtain correlation characteristics between temperature and viscosity; The attenuation relationship between suspended particles and temperature in the water body to be measured is determined according to the correlation characteristics.

2. The method according to claim 1, wherein Synchronously fitting the scattered light signal and the light signal of the environmental background corresponding to the water body to be tested to obtain the scattering difference characteristics of the suspended particles in the water body to be tested specifically includes: Collecting the light signal of the environmental background corresponding to the water body to be measured; Preprocessing the scattered light signal and the light signal of the environmental background to obtain a preprocessed scattered light signal and a preprocessed light signal of the environmental background; Performing time series alignment on the preprocessed scattered light signal and the preprocessed ambient background light signal to obtain a time series signal data set; The light scattering difference characteristics of suspended particles in the water body to be tested are extracted from the time series signal data set.

3. The method according to claim 1, wherein Determining the disturbance error of the flow velocity in the measured water body on the measurement of suspended particles specifically includes: Obtaining a three-dimensional flow velocity distribution of the water body to be measured; Determine the horizontal loss and vertical loss of suspended particles due to the flow velocity in the water body to be measured according to the three-dimensional flow velocity distribution; The disturbance error of the flow velocity in the water body to be measured on the measurement of suspended particles is determined by the horizontal loss and the vertical loss.

4. The method according to claim 1, wherein Performing turbidity inversion on the suspended particles in the water body to be measured based on the turbidity inversion model in combination with the scattering difference characteristics and the disturbance error to obtain the turbidity gradient of the suspended particles in the water body to be measured specifically includes: performing normalization processing on the scattering difference feature to obtain a standardized scattering difference feature; The turbidity gradient of suspended particles in the water body to be measured is determined based on the turbidity inversion model combined with the standardized scattering difference characteristics and the disturbance error.

5. The method according to claim 1, wherein Determining the viscosity state of the water body dynamics in the water body to be measured specifically includes: Monitoring temperature, salinity and pressure data at different depths in the water body to be measured; The viscosity state of the water body dynamics in the water body to be measured is determined based on the temperature, salinity and pressure data at different depths.

6. The method according to claim 1, wherein Dynamically compensating the turbidity gradient of suspended particles in the water body to be measured by using the attenuation relationship, and then obtaining the dynamic turbidity value of the water body to be measured specifically includes: Dynamically compensating the turbidity gradient of suspended particles in the water body to be measured according to the attenuation relationship to obtain a compensated turbidity gradient; The dynamic turbidity value of the water body to be measured is determined by the compensated turbidity gradient.

7. The method according to claim 1, wherein A photoelectric detector is used to collect the scattered light signal of the water body to be measured.

8. The method according to claim 1, wherein A machine learning algorithm is used to construct a turbidity inversion model of the water body to be measured.

9. A water turbidity measurement system for water ecological survey, the system adopting the method according to any one of claims 1 to 8 to measure water turbidity, characterized in that: The system includes: An acquisition module, configured to alternately illuminate the water body to be measured and acquire scattered light signals of the water body to be measured; a processing module for synchronously fitting the scattered light signal and the light signal of the environmental background corresponding to the water body to be measured, obtaining the scattering difference characteristics of the suspended particles in the water body to be measured, and determining the disturbance error of the flow velocity in the water body to measure the suspended particles; The processing module is further configured to construct a turbidity inversion model for the water body to be tested, and perform turbidity inversion on the suspended particles in the water body to be tested based on the turbidity inversion model in combination with the scattering difference characteristics and the disturbance error, to obtain a turbidity gradient of the suspended particles in the water body to be tested; The processing module is further configured to determine the viscosity state of the water body dynamics in the water body to be tested, and determine the attenuation relationship between the suspended particles in the water body to be tested and the temperature based on the viscosity state and the fluctuation characteristics of the ambient temperature of the water body to be tested; An execution module is used to dynamically compensate the turbidity gradient of suspended particles in the water body to be measured according to the attenuation relationship, thereby obtaining a dynamic turbidity value of the water body to be measured.

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