A method, device, equipment and medium for processing sunlight-induced chlorophyll fluorescence observation data

Abstract

The present application discloses a method, device, equipment and medium for processing sunlight-induced chlorophyll fluorescence observation data, wherein the method comprises: first, based on empirical statistical relationships, by constructing the connection relationship between complex parameters and vegetation indices, generating simplified model parameters. Afterwards, based on these parameters, by calculating the SIF ratio of pure vegetation single scattering escape, the SIF ratio of pure soil single scattering escape, and the SIF ratio of soil-vegetation scattering escape, the single vegetation scattering escape rate, the single soil scattering escape rate and the soil-vegetation scattering escape rate are generated. Finally, based on the above three aspects of escape rates, the downscaling calculation formula is constructed to complete the downscaling processing of the SIF observation data. The present application realizes the precise quantification of the influence of soil background on the fluorescence escape probability, ensures the simplicity of the calculation process, and improves the wide applicability of downscaling in sparse canopy and bright soil background.

Description

Technical Field

[0001] The present disclosure relates to remote sensing data processing technology, and in particular to a method, device, equipment and medium for processing sunlight-induced chlorophyll fluorescence observation data. Background Art

[0002] Studies in recent years have found that the generation mechanism of solar-induced chlorophyll fluorescence (SIF) is closely related to physiological conditions such as the photosynthetic capacity and photosynthetic physiological characteristics of vegetation. SIF can identify changes in the photosynthetic state of vegetation earlier and more sensitively, and has therefore been proven to be an effective method for predicting the gross primary productivity (GPP) of vegetation. However, the SIF signal detected by the sensor only represents the fluorescence information at the canopy scale, and due to the scattering and reabsorption effects inside the canopy, the captured canopy-scale SIF signal only reflects a part of the SIF photons emitted at the leaf level. Moreover, unlike the close physiological correlation at the leaf level, the relationship between SIF and GPP at the canopy level is significantly affected by the canopy structure and angle effects. Fluorescence escape probability (f esc ) describes the probability of SIF photons escaping from the top of the canopy and reaching the sensor. It is the canopy SIF (SIF canopy ) and the total SIF emitted by the blade (SIF leaf ) is the key bridge between them. This makes it possible to accurately estimate f esc The influence of canopy structure and angle effects can be eliminated, thereby better revealing the physiological coupling mechanism between SIF and GPP, improving the accuracy of GPP estimation, and helping to understand the changes in the photosynthetic state of global vegetation.

[0003] At present, although the spectral invariance theory has been successfully applied to the canopy-to-leaf scale downscaling study of SIF in the near-infrared band, many scholars have also proposed f esc However, these commonly used near-infrared bands f esc There is a common problem with the estimation methods: they ignore the interaction between the soil background and the vegetation canopy. Under sparse canopy conditions, these methods have a poor performance on f esc There are certain limitations to the estimates.

[0004] Therefore, one or more methods are needed to solve the above problems.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the Invention

[0006] The purpose of the present disclosure is to provide a method and apparatus, device and medium for processing sunlight-induced chlorophyll fluorescence observation data, thereby overcoming one or more problems caused by the limitations and defects of related technologies to at least a certain extent.

[0007] According to one aspect of the present disclosure, a method for processing sunlight-induced chlorophyll fluorescence observation data is provided, comprising:

[0008] Based on empirical statistical relationships, the connection between complex parameters and vegetation indices is constructed to generate simplified model parameters;

[0009] Based on the simplified parameters of the model, the single-shot vegetation scattering escape rate is generated by calculating the proportion of sunlight-induced chlorophyll fluorescence photons that escape single scattering from pure vegetation.

[0010] Based on the simplified parameters of the model, the single soil scattering escape rate is generated by calculating the proportion of sunlight-induced chlorophyll fluorescence photons that escape single scattering from pure soil;

[0011] Based on the simplified parameters of the model, the scattering escape rate between soil and vegetation is generated by calculating the proportion of sunlight-induced chlorophyll fluorescence photons that escape between soil and vegetation;

[0012] Based on the single vegetation scattering escape rate, the single soil scattering escape rate, and the scattering escape rate between soil and vegetation, a downscaling calculation formula between the canopy level and the leaf level is constructed to complete the downscaling processing of the sunlight-induced chlorophyll fluorescence observation data.

[0013] In an exemplary embodiment of the present disclosure, an empirical statistical relationship between complex parameters and vegetation indices is constructed, including:

[0014] Based on the directionality of sunlight-induced chlorophyll fluorescence photons, a single direction parameter is generated by setting the escape direction of sunlight-induced chlorophyll fluorescence photons;

[0015] Based on the spectral invariance theory, the canopy interception rate is generated by equivalently replacing the proportion of photosynthetically active radiation absorbed by vegetation.

[0016] Based on the preset measured data, the scattering characteristics of the leaves in the near-infrared band are measured to generate the single scattering albedo of the leaves in the near-infrared band.

[0017] Based on remote sensing technology, the spectral reflectance of soil samples is measured to generate soil reflectance in the near-infrared band;

[0018] Based on the principle of radiation transfer, the single-directional reflectance in the near-infrared band is generated by performing radiation and geometric correction on the escape direction of sunlight-induced chlorophyll fluorescence photons on remote sensing image data.

[0019] Based on remote sensing image data, the vertical observation index is generated by calculating the normalized difference vegetation index in the vertical observation direction;

[0020] Based on remote sensing image data, the single-direction porosity is generated by calculating the proportion of soil observed in the escape direction of sunlight-induced chlorophyll fluorescence photons.

[0021] In an exemplary embodiment of the present disclosure, the proportion of sunlight-induced chlorophyll fluorescence photons that escape single scattering from pure vegetation is calculated, including:

[0022] Based on remote sensing image data, the normalized difference vegetation index of the escape direction of sunlight-induced chlorophyll fluorescence photons is calculated to generate a single direction observation index.

[0023] Based on the single-direction reflectivity and single-direction observation index in the near-infrared band, the vegetation infrared reflectivity is generated by calculating the reflectivity of the escape direction of sunlight-induced chlorophyll fluorescence photons in the near-infrared band of the vegetation;

[0024] Based on the radiation transmission principle, the proportion of sunlight-induced chlorophyll fluorescence that escapes single scattering of pure vegetation is calculated through the canopy interception rate, the single scattering albedo of leaves in the near-infrared band, and the infrared reflectivity of vegetation to generate the single vegetation scattering escape rate.

[0025] In an exemplary embodiment of the present disclosure, the ratio of sunlight-induced chlorophyll fluorescence photons escaping single scattering from pure soil is calculated, including:

[0026] Based on empirical statistical relationships, the canopy bottom escape rate was generated by calculating the ratio of sunlight-induced chlorophyll fluorescence photons escaping from the canopy bottom to the total sunlight-induced chlorophyll fluorescence photons emitted by the leaves.

[0027] Based on the scattering effect between soil and vegetation, the proportion of sunlight-induced chlorophyll fluorescence that escapes from single scattering of pure soil is calculated through the canopy bottom escape rate, soil reflectivity in the near-infrared band, and porosity in a single direction to generate the single soil scattering escape rate.

[0028] In an exemplary embodiment of the present disclosure, the ratio of sunlight-induced chlorophyll fluorescence photons scattered and escaped between soil and vegetation is calculated, including:

[0029] Based on the spectral invariance theory, the intercepted photon rate is generated by calculating the vegetation interception ratio of chlorophyll fluorescence photons induced by soil-reflected sunlight;

[0030] Based on the spectral invariance theory, the calculation formula of the scattering value of vegetation intercepted photons in the direction of escape of sunlight-induced chlorophyll fluorescence photons is constructed to generate the first scattering formula.

[0031] Among them, α(Ω) is the escape probability in the Ω direction, p is the re-collision probability, ω L Single scattering albedo of leaves in the near-infrared band, i F is the photon interception rate.

[0032] In an exemplary embodiment of the present disclosure, the ratio of sunlight-induced chlorophyll fluorescence photons scattered and escaped between soil and vegetation is calculated, further comprising:

[0033] Based on the spectral invariance theory, the first scattering formula is simplified by the single-directional reflectivity of the near-infrared band to generate the second scattering formula

[0034] in, It is the single directional reflectance of pure vegetation in the near infrared band and can be replaced by NIRv(Ω). NIRv(Ω) is the product of the normalized difference vegetation index NDVI and the Ω directional reflectance of the canopy in the near infrared band. BRF NIR (Ω) is the reflectivity in the near-infrared band Ω observation direction, BRF Red (Ω) is the reflectivity of the red light band in the Ω observation direction; i0 is the canopy interception rate.

[0035] Based on the scattering effect between the soil and the vegetation, the ratio of sunlight-induced chlorophyll fluorescence scattered and escaped between the soil and the vegetation is calculated using the second scattering formula to generate a scattering escape rate between the soil and the vegetation.

[0036] In an exemplary embodiment of the present disclosure, a downscaling model between the canopy level and the leaf level is constructed, including:

[0037] Based on the spectrum invariance theory, the fluorescence escape rate is generated by integrating the single vegetation scattering escape rate, the single soil scattering escape rate, and the scattering escape rate between soil and vegetation;

[0038] Based on the fluorescence escape rate, a downscaling calculation formula is generated by calculating the correlation between the canopy sunlight-induced chlorophyll fluorescence and the total sunlight-induced chlorophyll fluorescence at the leaf level;

[0039] Based on the sunlight-induced chlorophyll fluorescence signal at the canopy scale, the sunlight-induced chlorophyll fluorescence signal at the leaf scale is calculated using the downscaling calculation formula to complete the downscaling processing of the sunlight-induced chlorophyll fluorescence observation data.

[0040] In one aspect of the present disclosure, a device for processing sunlight-induced chlorophyll fluorescence observation data is provided, comprising:

[0041] The parameter simplification acquisition module is used to construct the connection relationship between complex parameters and vegetation indices;

[0042] The single vegetation scattering contribution calculation module is used to calculate the proportion of sunlight-induced chlorophyll fluorescence photons that escape through single scattering of pure vegetation;

[0043] Single soil scattering contribution calculation module, used to calculate the proportion of sunlight-induced chlorophyll fluorescence photons that escape through single scattering of pure soil;

[0044] The soil-vegetation scattering contribution calculation module is used to calculate the proportion of sunlight-induced chlorophyll fluorescence photons that escape through scattering between the soil and vegetation;

[0045] The data downscaling processing module is used to complete the downscaling processing of sunlight-induced chlorophyll fluorescence observation data by constructing a downscaling calculation formula between the canopy level and the leaf level.

[0046] In one aspect of the present disclosure, there is provided an electronic device, comprising:

[0047] processor; and

[0048] A memory having computer-readable instructions stored thereon, wherein the computer-readable instructions, when executed by the processor, implement the method according to any one of the above items.

[0049] In one aspect of the present disclosure, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the method according to any one of the above items is implemented.

[0050] Based on the embodiment of the present disclosure, first, based on the empirical statistical relationship, the connection relationship between the complex parameters and the vegetation index is constructed to generate the simplified parameters of the model. Then, based on these parameters, the single vegetation scattering escape rate is generated by calculating the ratio of sunlight-induced chlorophyll fluorescence that escapes single scattering of pure vegetation; at the same time, the single soil scattering escape rate is generated by calculating the ratio of sunlight-induced chlorophyll fluorescence that escapes single scattering of pure soil; and the scattering escape rate between soil and vegetation is generated by calculating the ratio of sunlight-induced chlorophyll fluorescence that escapes scattered between soil and vegetation. Finally, based on the escape rates calculated from the above three aspects, the downscaling calculation formula between the canopy level and the leaf level is constructed to complete the downscaling processing of the sunlight-induced chlorophyll fluorescence observation data. Therefore, the embodiment of the present disclosure provides an f based on the interaction between soil and canopy. escModeling scheme, which can realize soil background esc The precise quantification of the impact ensures the simplicity of the calculation process and promotes its wide applicability in sparse canopy and bright soil backgrounds.

[0051] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

[0052] The technical solution of the present disclosure is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0054] The present disclosure can be more clearly understood from the following detailed description with reference to the accompanying drawings, in which:

[0055] Figure 1 This is a flow chart of a method for processing sunlight-induced chlorophyll fluorescence observation data according to one embodiment of the disclosed method;

[0056] Figure 2 A schematic diagram of three contributing sources of canopy SIF observed by a sensor in a method for processing sunlight-induced chlorophyll fluorescence observation data according to an embodiment of the disclosed method;

[0057] Figure 3 This is a schematic diagram of the radiation transmission process of SIF photons re-entering the canopy after being reflected by the soil in a method for processing sunlight-induced chlorophyll fluorescence observation data according to one embodiment of the disclosed method;

[0058] Figure 4 This is a structural block diagram of a device for processing sunlight-induced chlorophyll fluorescence observation data according to an embodiment of the disclosed method;

[0059] Figure 5 A block diagram of an electronic device according to an embodiment of the disclosed method. DETAILED DESCRIPTION

[0060] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art. Like reference numerals in the drawings represent like or similar parts, and thus repetitive description thereof will be omitted.

[0061] In addition, the described features, structures or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure can be practiced without one or more of the specific details, or other methods, components, materials, devices, steps, etc. can be adopted. In other cases, well-known structures, methods, devices, implementations, materials or operations are not shown or described in detail to avoid obscuring various aspects of the present disclosure.

[0062] The blocks shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically separate entities. Specifically, these functional entities may be implemented in software, or in one or more software-hardened modules, or in different networks and / or processor devices and / or microcontroller devices.

[0063] In the embodiment of the present disclosure, a method for processing sunlight-induced chlorophyll fluorescence observation data is first provided; in particular, a downscaling method for sunlight-induced chlorophyll fluorescence observation data is provided. Figure 1 As shown in , the method for processing sunlight-induced chlorophyll fluorescence observation data may include the following steps:

[0064] Step S110 , generating simplified model parameters by constructing a connection relationship between complex parameters and vegetation indices based on empirical statistical relationships;

[0065] Step S120, based on the simplified model parameters, calculating the proportion of sunlight-induced chlorophyll fluorescence photons that escape single scattering from pure vegetation to generate a single vegetation scattering escape rate;

[0066] Step S130, based on the simplified model parameters, calculating the ratio of sunlight-induced chlorophyll fluorescence photons that escape single scattering from pure soil to generate a single soil scattering escape rate;

[0067] Step S140, based on the simplified model parameters, calculating the ratio of sunlight-induced chlorophyll fluorescence photons scattered and escaped between the soil and vegetation to generate a scattering escape rate between the soil and vegetation;

[0068] Step S150, based on the single vegetation scattering escape rate, the single soil scattering escape rate, and the scattering escape rate between soil and vegetation, a downscaling calculation formula between the canopy level and the leaf level is constructed to complete the downscaling processing of the sunlight-induced chlorophyll fluorescence observation data.

[0069] Next, a method for processing sunlight-induced chlorophyll fluorescence observation data in an embodiment of the present disclosure will be further described.

[0070] In step S110 , based on empirical statistical relationships, simplified model parameters may be generated by constructing a connection relationship between complex parameters and vegetation indices.

[0071] In some optional embodiments of this example, Figure 2 As shown in the figure, based on the similarity between the radiation transmission process of chlorophyll fluorescence (SIF) in the canopy and the reflectance signal, the canopy SIF (SIF canopy ) signal mainly comes from three aspects: one is the single scattering contribution of pure vegetation (SIF v ), and the second is the single scattering contribution of pure soil (SIF s ), and the third is the multiple scattering contribution between soil and vegetation (SIF m In addition, when calculating the fluorescence escape rate (f esc ), in order to simplify the processing, the ratio is converted into a dimensionless quantity in the example of the present invention, and only the near-infrared band is considered.

[0072] However, before starting the calculation, the parameters needed in the calculation formula need to be obtained. First, by setting the directional parameters of the escaping sunlight-induced chlorophyll fluorescence photons, a single directional parameter Ω is generated.

[0073] Secondly, based on the practical application of many studies, the interception probability of the canopy is directly replaced by the proportion of photosynthetically active radiation absorbed by vegetation, FAPAR, to generate the canopy interception rate i0. In a specific embodiment, a digital camera is used to capture a color image of a low canopy to obtain photosynthetically active radiation (PAR), and a reference white board is included in one corner of the image. The digital photo pixels are then classified into green vegetation, dead branches and leaves on the ground, sunlit soil, shaded soil, and a reference white board. The incident PAR (PAR) is obtained from the digital camera image. i ), scene reflection PAR (PAR r ), bare soil absorbs PAR (PAR s and green vegetation absorbs PAR (PAR v ) and then calculate FAPAR. The specific calculation formula is as follows:

[0074] Thirdly, the scattering characteristics of the leaves in the near-infrared band are measured through big data experiments, or optical models (such as radiation transfer models) are used to estimate the albedo probability of single scattering of leaves in the near-infrared band to generate the single scattering albedo of leaves in the near-infrared band ω L In one embodiment, according to the simulation results of one-dimensional and three-dimensional canopy radiation transfer models, ω LIt is relatively stable in the near-infrared band and can be directly used to obtain ω L =1.

[0075] Fourthly, the soil reflectance r in the near-infrared band is obtained by using ground-measured data (such as the spectral reflectance of soil samples) and then correcting the reflectance of remote sensing images. s .

[0076] Fifthly, based on the principle of radiation transfer, by using image data taken by remote sensing satellites or drones, combined with radiation correction and geometric correction technology, or through existing remote sensing databases (such as MODIS, Landsat), the single directional reflectance BRF in the near-infrared band in the Ω direction (i.e., the direction of escape of sunlight-induced chlorophyll fluorescence photons) is obtained. NIR (Ω), single direction reflectivity BRF in the red light band Red (Ω).

[0077] Sixth, based on remote sensing image data, through the formula Calculate the normalized difference vegetation index in the vertical observation direction to generate the vertical observation index NDVI nadir Among them, Ω0 means the observation zenith angle (VZA) is 0 degrees, that is, vertical observation, BRF NIR (Ω0) is the reflectivity in the vertical observation direction of the near-infrared band, BRF Red (Ω0) is the reflectivity in the vertical observation direction of the red light band.

[0078] The two vertical observation direction reflectivities here can also be obtained by using image data taken by remote sensing satellites or drones, combined with radiation correction and geometric correction techniques, or through existing remote sensing databases (such as MODIS and Landsat).

[0079] Seventh, according to the definition of remote sensing database, the single direction porosity P in the Ω direction in this example is o The value range of (Ω) is 0 to 1. When the vegetation coverage is very low, P o (Ω) approaches 1; when the vegetation coverage is very high, P o (Ω) approaches 0. Moreover, the porosity in a single direction decreases with the increase of leaf area index (LAI) and observation zenith angle (VZA), because when LAI and VZA are higher, less soil is visible in the observation direction.

[0080] Therefore, we use NIRv (the product of the vertical observation index and the near-infrared canopy Ω directional reflectance) to calculate P o (Ω) is used for modeling. The vertical observation index (NDVI nadir ) contains P o(Ω), single direction reflectance in the near infrared band (BRF NIR (Ω)) contains P o The angle information in (Ω). The specific calculation formula is as follows: o (Ω)=1-2.331×NIRv=1-2.331×NDVI nadir ×BRF NIR (Ω), where P o When (Ω) is less than 0, it is directly taken as 0.

[0081] In this way, the empirical statistical relationship between the complex parameters required in the downscaling calculation process and the vegetation index is established, which solves the problem of difficult calculation process and improves the simplicity and practicality of calculation.

[0082] In step S120, based on the simplified parameters of the model, the single vegetation scattering escape rate can be generated by calculating the proportion of sunlight-induced chlorophyll fluorescence photons that escape single scattering from pure vegetation.

[0083] In some optional embodiments of this example, it is assumed that under the background of black soil, the proportion of SIF photons that escape directly from the top of the vegetation canopy in the near-infrared band Ω direction (i.e., the direction of escape of sunlight-induced chlorophyll fluorescence photons) is fesc. v (Ω) can be calculated according to the formula Make an estimate.

[0084] Among them, NIRv(Ω) is the infrared reflectivity of vegetation, that is, the product of the single-direction observation index and the single-direction reflectivity of the near-infrared band. Specifically, it can be obtained by the formula NIRv(Ω)=NDVI Ω ×BRF NIR (Ω)Complete calculation.

[0085] Then, according to the single-direction reflectivity of the near-infrared band in the Ω direction (i.e., the escape direction of sunlight-induced chlorophyll fluorescence photons) and the single-direction reflectivity of the red light band in the Ω direction, the formula Calculate the normalized difference vegetation index in the Ω direction to generate the NDVI observation index in the Ω direction Ω .

[0086] All the parameters are now available. By substituting the parameters into the equation, the single vegetation scattering escape rate calculation formula is generated: Complete the single vegetation scattering escape rate (fesc v (Ω)) calculation.

[0087] In step S130, based on the simplified parameters of the model, the single soil scattering escape rate can be generated by calculating the proportion of sunlight-induced chlorophyll fluorescence photons that escape single scattering from pure soil.

[0088] In some optional embodiments of this example, the SIF photons that escape from the bottom of the vegetation canopy to the soil, are then reflected by the soil and directly reach the sensor through the gaps in the vegetation canopy are pure soil single scattering escape SIF, which accounts for a proportion of the total SIF photons emitted by the leaves (fesc s (Ω)) can be expressed by the formula Perform calculations.

[0089] Among them SIF BOC SIF is the sunlight-induced chlorophyll fluorescence photon escaping from the canopy bottom. leaf is the total sunlight-induced chlorophyll fluorescence photons emitted by leaves, and the ratio of sunlight-induced chlorophyll fluorescence photons escaping from the bottom of the canopy to the total sunlight-induced chlorophyll fluorescence photons emitted by leaves is the canopy bottom escape rate, that is,

[0090] According to the definition of remote sensing database, f SIFdown The value range of f is 0~0.5. When the vegetation coverage is very low, f SIFdown Approaches 0.5; when the vegetation coverage is very high, f SIFdown approaches 0. And f SIFdown It decreases with increasing LAI but is almost independent of the observation direction.

[0091] Therefore, according to 0.5-f SIFdown The empirical statistical relationship between the vertically observed vegetation index and f SIFdown The parameterized model formula is:

[0092] Then all available parameters are brought in to generate the solution formula for the single soil scattering escape rate: Complete the single soil scattering escape rate (fesc s (Ω)).

[0093] In step S140, based on the simplified parameters of the model, the ratio of sunlight-induced chlorophyll fluorescence photons scattered and escaped between the soil and vegetation can be calculated to generate a scattering escape rate between the soil and vegetation.

[0094] In some optional embodiments of this example, Figure 3 As shown in the figure, the ratio of SIF photons that escape from the bottom of the canopy to the soil and then re-enter the canopy after being reflected by the soil is the intercepted photon rate i F, can refer to the reflected signal radiation transmission process. The only difference between the two is that in the reflected signal calculation model, the solar photons enter the canopy from top to bottom, while in the example of the present invention, the SIF photons are reflected by the soil and then enter the canopy upward. Therefore, through formula i F =f SIFdown ×r s ×i0 can be used to calculate the intercepted photon rate.

[0095] At the same time, similar to the calculation model of the reflected signal, according to the spectrum invariance theory, the intercepted photon rate can be divided into three destinations: one is the part absorbed by the canopy, i.e. F (1-ω L ); the second is the part that escapes directly from the canopy, i F ω L (1-p), where p represents the probability of re-collision; the third is the part that is scattered multiple times in the canopy until it leaves the canopy, i.e. F ω L p.

[0096] Therefore, the proportion of SIF photons that escape from the bottom of the canopy to the soil, are reflected by the soil and re-enter the canopy, and then escape from the top of the canopy after interacting with vegetation (s F ) can be expressed as: Then calculate the infinite geometric sequence and you can get where (1-p) is the overall canopy density in all directions within the unit sphere.

[0097] However, we do not need the escape rate of the entire spherical space, but only the escape rate in a specific Ω direction, that is, the scattering escape rate fesc between soil and vegetation m (Ω). Therefore, by constructing the first scattering formula The proportion of photons escaping in the direction of sunlight-induced chlorophyll fluorescence photons (Ω direction) is calculated, where α(Ω) is the probability of these SIF photons escaping in the Ω direction.

[0098] In some optional embodiments of this example, Figure 3 As shown in Figure 1, only the first scattering between the soil and the canopy is considered, while the second-order and higher-order scattering between the soil and the canopy is ignored (mainly because the subsequent scattering processes account for a very small proportion). Therefore, after the soil first reflects the SIF photons escaping downward from the canopy bottom, the soil background no longer plays a role and can be regarded as a black soil background. At this point, using spectral invariance theory, the canopy BRF against the black soil background simplifies the first scattering formula mentioned above.

[0099] At this time, the single direction reflectivity of the pure vegetation infrared band Right now and It can be replaced by NIRv(Ω) and brought into the first scattering formula to generate the second scattering formula This formula is used to calculate the scattering escape rate between soil and vegetation.

[0100] In step S150, based on the single vegetation scattering escape rate, the single soil scattering escape rate, and the scattering escape rate between soil and vegetation, a downscaling calculation formula between the canopy level and the leaf level can be constructed to complete the downscaling processing of the sunlight-induced chlorophyll fluorescence observation data.

[0101] In some optional embodiments of this example, when calculating the fluorescence escape rate (f esc ), it can be derived by the following formula:

[0102]

[0103] where fesc v (Ω), fesc s (Ω), fesc m The calculation formula of (Ω) has been obtained through the above steps, so,

[0104]

[0105] Moreover, each parameter in the formula can be obtained by searching, calculating, and measuring. Then, the calculated fluorescence escape rate is substituted into The downscaling calculation formula can be constructed, and the correlation between the canopy sunlight-induced chlorophyll fluorescence and the total sunlight-induced chlorophyll fluorescence at the leaf level can be used to calculate the downscaling formula. After the canopy-scale sunlight-induced chlorophyll fluorescence signal has been observed (i.e., the SIF is known), the downscaling calculation formula can be constructed. canopy ), sunlight-induced chlorophyll fluorescence signal (SIF) at the leaf scale leaf ) is calculated to complete the downscaling of the sunlight-induced chlorophyll fluorescence observation data. esc The calculation is divided into three parts (single vegetation scattering escape rate, single soil scattering escape rate, and soil-vegetation scattering escape rate), which can fully quantify the effect of soil background on f esc It can be better applied to scenes with sparse canopy and bright soil background.

[0106] It should be noted that although the steps of the method disclosed herein are depicted in a particular order in the accompanying drawings, this does not require or imply that the steps must be performed in that particular order, or that all steps must be performed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one, and / or one step may be decomposed into multiple steps.

[0107] In addition, in this exemplary embodiment, a device for processing sunlight-induced chlorophyll fluorescence observation data is also provided. Figure 4 As shown, the device 400 for processing sunlight-induced chlorophyll fluorescence observation data may include: a parameter simplification acquisition module 410, a single vegetation scattering contribution calculation module 420, a single soil scattering contribution calculation module 430, a soil-vegetation scattering contribution calculation module 440, and a data downscaling processing module 450. Among them:

[0108] The parameter simplification acquisition module 410 is used to construct a connection relationship between complex parameters and vegetation indices;

[0109] The single vegetation scattering contribution calculation module 420 is used to calculate the proportion of sunlight-induced chlorophyll fluorescence photons that escape through single scattering of pure vegetation;

[0110] The single soil scattering contribution calculation module 430 is used to calculate the proportion of sunlight-induced chlorophyll fluorescence photons that escape through single scattering of pure soil;

[0111] The soil-vegetation scattering contribution calculation module 440 is used to calculate the ratio of sunlight-induced chlorophyll fluorescence photons that escape through scattering between the soil and vegetation;

[0112] The data downscaling processing module 450 is used to complete the downscaling processing of the sunlight-induced chlorophyll fluorescence observation data by constructing a downscaling calculation formula between the canopy level and the leaf level.

[0113] The apparatus for processing sunlight-induced chlorophyll fluorescence observation data according to the embodiment of the present disclosure corresponds to the embodiment of the method for processing sunlight-induced chlorophyll fluorescence observation data according to the present disclosure, and the relevant contents can be referenced to each other and are not further described here. The beneficial technical effects corresponding to the apparatus for processing sunlight-induced chlorophyll fluorescence observation data according to the embodiment of the present disclosure can be referred to in the corresponding beneficial technical effects of the corresponding exemplary method section above, and are not further described here.

[0114] It should be noted that although the above detailed description mentions several modules or units of the device 400 for processing sunlight-induced chlorophyll fluorescence observation data, this division is not mandatory. In fact, according to embodiments of the present disclosure, the features and functions of two or more modules or units described above can be embodied in a single module or unit. Conversely, the features and functions of a single module or unit described above can be further divided and embodied by multiple modules or units.

[0115] Below, reference Figure 5 The electronic device according to the embodiment of the present disclosure is described. The electronic device may be either or both of the first device and the second device, or a standalone device independent of them, and the standalone device may communicate with the first device and the second device to receive collected input signals from them.

[0116] Figure 5 A block diagram of an electronic device according to an embodiment of the present disclosure is illustrated.

[0117] like Figure 5 As shown, the electronic device includes one or more processors and memory.

[0118] The processor may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions.

[0119] The memory may store one or more computer program products, and the memory may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), a hard disk, flash memory, etc. One or more computer program products may be stored on the computer-readable storage medium, and the processor may execute the computer program products to implement the various embodiments and methods of the present disclosure described above and / or other desired functions.

[0120] In one example, the electronic device may further include an input device and an output device, and these components are interconnected via a bus system and / or other forms of connection mechanisms (not shown).

[0121] In addition, the input device may also include, for example, a keyboard, a mouse, and the like.

[0122] The output device can output various information to the outside, including determined distance information, direction information, etc. The output device can include, for example, a display, a speaker, a printer, a communication network and a remote output device connected thereto, and the like.

[0123] Of course, to simplify, Figure 5 Only some of the components related to the present disclosure in the electronic device are shown, and components such as a bus, an input / output interface, etc. are omitted. In addition, the electronic device may further include any other appropriate components according to specific application scenarios.

[0124] In addition to the above-mentioned methods and devices, an embodiment of the present disclosure may also be a computer program product, which includes computer program instructions, which, when executed by a processor, enable the processor to execute the steps of the method according to various embodiments of the present disclosure described in the above part of this specification.

[0125] The computer program product may be written in any combination of one or more programming languages to implement the operations of the disclosed embodiments, including object-oriented programming languages such as Java, C++, and conventional procedural programming languages such as C or similar programming languages. The program code may be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0126] In addition, an embodiment of the present disclosure may also be a computer-readable storage medium having computer program instructions stored thereon, which, when executed by a processor, causes the processor to execute the steps of the method according to various embodiments of the present disclosure described in the above part of this specification.

[0127] The computer-readable storage medium can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can, for example, include but is not limited to a system, device or component of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination thereof. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0128] The basic principles of the present disclosure have been described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, and effects mentioned in this disclosure are merely illustrative and not restrictive, and should not be construed as necessarily possessed by each embodiment of the present disclosure. Furthermore, the specific details disclosed above are provided for illustrative purposes and to facilitate understanding, rather than as limitations. These details do not limit the present disclosure to necessarily being implemented using these specific details.

[0129] Each embodiment in this specification is described in a progressive manner, with each embodiment focusing on its differences from the other embodiments. References to the same or similar parts between the various embodiments are sufficient. For system embodiments, since they largely correspond to method embodiments, their description is relatively simple. For relevant parts, references to the description of the method embodiments are sufficient.

[0130] The block diagrams of the devices, devices, equipment, and systems involved in this disclosure are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As will be appreciated by those skilled in the art, these devices, devices, equipment, and systems can be connected, arranged, or configured in any manner. Words such as "include," "comprise," "have," and the like are open-ended words, meaning "including but not limited to," and can be used interchangeably therewith. The words "or" and "and" used herein refer to the words "and / or" and can be used interchangeably therewith, unless the context clearly indicates otherwise. The word "such as" used herein refers to the phrase "such as but not limited to," and can be used interchangeably therewith.

[0131] The methods and apparatus of the present disclosure may be implemented in many ways. For example, the methods and apparatus of the present disclosure may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above order of steps for the method is for illustration only, and the steps of the method of the present disclosure are not limited to the order specifically described above unless otherwise specified. In addition, in some embodiments, the present disclosure may also be implemented as programs recorded in a recording medium, which include machine-readable instructions for implementing the methods according to the present disclosure. Thus, the present disclosure also covers recording media that store programs for executing the methods according to the present disclosure.

[0132] It should also be noted that in the apparatus, device, and method of the present disclosure, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present disclosure.

[0133] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present disclosure. Therefore, the present disclosure is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0134] The above description has been provided for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present disclosure to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A method for processing sunlight-induced chlorophyll fluorescence observation data, characterized in that: include: According to the connection between complex parameters and vegetation index, the model is constructed and simplified model parameters are generated; Based on the simplified parameters of the model, the single-shot vegetation scattering escape rate is generated by calculating the proportion of sunlight-induced chlorophyll fluorescence photons that escape single scattering from pure vegetation. Based on the simplified parameters of the model, the single soil scattering escape rate is generated by calculating the proportion of sunlight-induced chlorophyll fluorescence photons that escape single scattering from pure soil; Based on the simplified parameters of the model, the scattering escape rate between soil and vegetation is generated by calculating the proportion of sunlight-induced chlorophyll fluorescence photons that escape between soil and vegetation; Based on the single vegetation scattering escape rate, the single soil scattering escape rate, and the soil-vegetation scattering escape rate, a downscaling calculation formula between the canopy level and the leaf level is constructed to complete the downscaling processing of the sunlight-induced chlorophyll fluorescence observation data; The method of constructing a model based on the connection between the complex parameters and the vegetation index and generating simplified model parameters specifically includes: Based on the directionality of sunlight-induced chlorophyll fluorescence photons, a single direction parameter is generated by setting the escape direction of sunlight-induced chlorophyll fluorescence photons; Based on the spectral invariance theory, the canopy interception rate is generated by equivalently replacing the proportion of photosynthetically active radiation absorbed by vegetation. Based on the preset measured data, the scattering characteristics of the leaves in the near-infrared band are measured to generate the single scattering albedo of the leaves in the near-infrared band. Based on remote sensing technology, the spectral reflectance of soil samples is measured to generate soil reflectance in the near-infrared band; Based on the principle of radiation transfer, the single-directional reflectance in the near-infrared band is generated by performing radiation and geometric correction on the escape direction of sunlight-induced chlorophyll fluorescence photons on remote sensing image data. Based on remote sensing image data, the vertical observation index is generated by calculating the normalized difference vegetation index in the vertical observation direction; Based on remote sensing image data, the porosity in a single direction is generated by calculating the proportion of soil observed in the escape direction of sunlight-induced chlorophyll fluorescence photons; The ratio of sunlight-induced chlorophyll fluorescence photons scattered and escaped between soil and vegetation is calculated, including: Based on the spectral invariance theory, the intercepted photon rate is generated by calculating the vegetation interception ratio of chlorophyll fluorescence photons induced by soil-reflected sunlight; Based on the spectral invariance theory, the calculation formula of the scattering value of vegetation intercepted photons in the direction of escape of sunlight-induced chlorophyll fluorescence photons is constructed to generate the first scattering formula. ; in, for The escape probability in the direction, p is the re-collision probability, Single scattering albedo of leaves in the near-infrared band, is the intercepted photon rate; By calculating the proportion of sunlight-induced chlorophyll fluorescence photons scattered and escaped between soil and vegetation, it also includes: Based on the spectral invariance theory, the first scattering formula is simplified by the single-directional reflectivity of the near-infrared band to generate the second scattering formula ; in, is the single-directional reflectance of pure vegetation in the near-infrared band, which can be obtained from Instead, is the normalized difference vegetation index NDVI and the near infrared band canopy The product of the directional reflectivities, , Near-infrared band Observation direction reflectivity, Red light band Reflectivity in the observation direction; is the canopy interception rate; Based on the scattering effect between the soil and the vegetation, the ratio of sunlight-induced chlorophyll fluorescence scattered and escaped between the soil and the vegetation is calculated using the second scattering formula to generate a scattering escape rate between the soil and the vegetation.

2. The method according to claim 1, characterized in that The proportion of sunlight-induced chlorophyll fluorescence photons that escape single scattering from pure vegetation is calculated, including: Based on remote sensing image data, the normalized difference vegetation index of the escape direction of sunlight-induced chlorophyll fluorescence photons is calculated to generate a single direction observation index. Based on the single-direction reflectivity and single-direction observation index in the near-infrared band, the vegetation infrared reflectivity is generated by calculating the reflectivity of the escape direction of sunlight-induced chlorophyll fluorescence photons in the near-infrared band of the vegetation; Based on the radiation transmission principle, the proportion of sunlight-induced chlorophyll fluorescence that escapes single scattering of pure vegetation is calculated through the canopy interception rate, the single scattering albedo of leaves in the near-infrared band, and the infrared reflectivity of vegetation to generate the single vegetation scattering escape rate.

3. The method according to claim 1, characterized in that The proportion of sunlight-induced chlorophyll fluorescence photons escaping single scattering from pure soil is calculated, including: Based on empirical statistical relationships, the canopy bottom escape rate was generated by calculating the ratio of sunlight-induced chlorophyll fluorescence photons escaping from the canopy bottom to the total sunlight-induced chlorophyll fluorescence photons emitted by the leaves. Based on the scattering effect between soil and vegetation, the proportion of sunlight-induced chlorophyll fluorescence that escapes from single scattering of pure soil is calculated through the canopy bottom escape rate, soil reflectivity in the near-infrared band, and porosity in a single direction to generate the single soil scattering escape rate.

4. The method according to any one of claims 1 to 3, characterized in that A downscaling model between the canopy level and the leaf level is constructed, including: Based on the spectrum invariance theory, the fluorescence escape rate is generated by integrating the single vegetation scattering escape rate, the single soil scattering escape rate, and the scattering escape rate between soil and vegetation; Based on the fluorescence escape rate, a downscaling calculation formula is generated by calculating the correlation between the canopy sunlight-induced chlorophyll fluorescence and the total sunlight-induced chlorophyll fluorescence at the leaf level; Based on the sunlight-induced chlorophyll fluorescence signal at the canopy scale, the sunlight-induced chlorophyll fluorescence signal at the leaf scale is calculated using the downscaling calculation formula to complete the downscaling processing of the sunlight-induced chlorophyll fluorescence observation data.

5. A device for processing sunlight-induced chlorophyll fluorescence observation data, characterized in that: The device adopts the method according to any one of claims 1 to 4, and the device comprises: The parameter simplification acquisition module is used to construct a model and generate simplified model parameters based on the connection relationship between complex parameters and vegetation index; The single vegetation scattering contribution calculation module is used to calculate the proportion of sunlight-induced chlorophyll fluorescence photons that escape through single scattering of pure vegetation; Single soil scattering contribution calculation module, used to calculate the proportion of sunlight-induced chlorophyll fluorescence photons that escape through single scattering of pure soil; The soil-vegetation scattering contribution calculation module is used to calculate the proportion of sunlight-induced chlorophyll fluorescence photons that escape through scattering between the soil and vegetation; The data downscaling processing module is used to complete the downscaling processing of sunlight-induced chlorophyll fluorescence observation data by constructing a downscaling calculation formula between the canopy level and the leaf level.

6. An electronic device, characterized in that: include: a memory for storing a computer program product; A processor is configured to execute the computer program product stored in the memory, and when the computer program product is executed, implements the method described in any one of claims 1 to 4 above.

7. A computer-readable storage medium having computer program instructions stored thereon, characterized in that: When the computer program instructions are executed by a processor, the method according to any one of claims 1 to 4 is implemented.

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