Vegetation growth evaluation method and system based on remote sensing technology

Abstract

The invention relates to the technical field of vegetation growth evaluation, and discloses a vegetation growth evaluation method and system based on a remote sensing technology, and the method comprises the steps: obtaining a real-time remote sensing image of a monitoring region; determining a normalized vegetation index of the monitoring area according to the real-time remote sensing image; determining the vegetation coverage and the vegetation coverage change rate of the monitoring area according to the normalized vegetation index; comparing the vegetation coverage change rate with a preset coverage change rate, and determining growth stages of the vegetation according to a comparison result, including an unaffected growth stage and a mutual affected growth stage; determining a vegetation growth evaluation grade according to the vegetation coverage change rate in a growth-unaffected stage; and determining the vegetation growth rate of the monitoring region according to the vegetation coverage and the area of the monitoring region in the mutual influence growth stage, and determining the vegetation growth evaluation grade according to the vegetation growth rate. According to the invention, the accuracy and efficiency of vegetation growth evaluation are improved, and the capability of monitoring the dynamic change of vegetation growth is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of vegetation growth assessment, and in particular to a vegetation growth assessment method and system based on remote sensing technology. Background Art

[0002] Vegetation growth assessment is an important part of agriculture, forestry and environmental monitoring. Traditional vegetation growth assessment methods mainly rely on ground surveys and sampling. Although this method is accurate, it is time-consuming and labor-intensive, and it is difficult to cover a large monitoring area. With the development of remote sensing technology, it has become possible to use satellite or aerial remote sensing images to perform vegetation growth assessment, which can provide fast and large-scale vegetation information. However, existing remote sensing technology still has some limitations in vegetation growth assessment, such as complex data processing, difficulty in accurately dividing vegetation growth stages, and the accuracy of assessment results needs to be improved. Therefore, the present invention proposes a new vegetation growth assessment method and system based on remote sensing technology to improve the efficiency and accuracy of vegetation growth assessment. Summary of the invention

[0003] The purpose of the present invention is to provide a vegetation growth assessment method and system based on remote sensing technology, aiming to solve the above problems.

[0004] The present invention provides a vegetation growth assessment method based on remote sensing technology, comprising:

[0005] Obtain real-time remote sensing images of the monitoring area;

[0006] Processing the real-time remote sensing image to obtain remote sensing data of the real-time remote sensing image, and determining a normalized vegetation index of the monitoring area according to the remote sensing data;

[0007] Determining the vegetation coverage of the monitoring area according to the normalized vegetation index, and determining the vegetation coverage change rate of the monitoring area according to the vegetation coverage;

[0008] Comparing the vegetation coverage change rate with a preset coverage change rate, and determining the growth stage of the vegetation according to the comparison result, wherein the growth stage includes a non-influence growth stage and a mutual influence growth stage;

[0009] When the growth stage is a non-impact growth stage, determining the vegetation growth assessment level of the monitoring area according to the vegetation coverage change rate;

[0010] When the growth stage is a mutually influencing growth stage, the vegetation growth rate of the monitoring area is determined according to the vegetation coverage and the area of ​​the monitoring area, and the vegetation growth assessment level of the monitoring area is determined according to the vegetation growth rate.

[0011] Preferably, when determining the normalized vegetation index of the monitoring area according to the remote sensing data, the normalized vegetation index is determined according to the following formula:

[0012]

[0013] Among them, NDVI represents the normalized difference vegetation index, p(NIR) represents the near-infrared band reflectance, and p(R) represents the red band reflectance.

[0014] Preferably, determining the vegetation coverage of the monitoring area according to the normalized difference vegetation index includes:

[0015] 5% of the cumulative frequency of the NDVI in the monitoring area is selected as the NDVI of non-vegetated pixels, and 95% of the cumulative frequency of the NDVI in the monitoring area is selected as the NDVI of vegetation pixels;

[0016] Determining the vegetation coverage of the monitoring area according to the normalized vegetation index, the normalized vegetation index of non-vegetation pixels and the normalized vegetation index of vegetation pixels;

[0017] The vegetation coverage is determined according to the following formula:

[0018]

[0019] Among them, FVC represents vegetation coverage, NDVI soi l Represents the normalized difference vegetation index of non-vegetated pixels, NDVI veg Represents the normalized difference vegetation index of vegetation pixels.

[0020] Preferably, comparing the vegetation coverage change rate with a preset coverage change rate, and determining the vegetation growth stage according to the comparison result, includes:

[0021] The vegetation coverage change rate is compared with the preset coverage change rate in chronological order. When the vegetation coverage change rate is less than the preset coverage change rate for the second time, the corresponding time point is determined as the demarcation time point, the time period before the demarcation time point is determined as the uninfluenced growth stage, and the time period after the demarcation time point is determined as the mutually influencing growth stage.

[0022] Preferably, when the growth stage is the non-impact growth stage, determining the vegetation growth assessment level of the monitoring area according to the vegetation coverage change rate includes:

[0023] A first preset change rate, a second preset change rate and a third preset change rate are set, and the first preset change rate, the second preset change rate and the third preset change rate increase in sequence;

[0024] Determining a vegetation growth assessment level of the monitoring area according to a relationship between the vegetation coverage change rate and the first preset change rate, the second preset change rate, and the third preset change rate;

[0025] If the vegetation coverage change rate is less than the first preset change rate, determining the vegetation growth assessment level of the monitoring area to be the first growth assessment level L1;

[0026] If the vegetation coverage change rate is greater than or equal to the first preset change rate, and the vegetation coverage change rate is less than the second preset change rate, then determining that the vegetation growth assessment level of the monitoring area is the second growth assessment level L2;

[0027] If the vegetation coverage change rate is greater than or equal to the second preset change rate, and the vegetation coverage change rate is less than the third preset change rate, then determining that the vegetation growth assessment level of the monitoring area is the third growth assessment level L3;

[0028] If the vegetation coverage change rate is greater than or equal to the third preset change rate, the vegetation growth assessment level of the monitored area is determined to be the fourth growth assessment level L4; wherein L1<L2<L3<L4.

[0029] Preferably, when the growth stage is a mutually influencing growth stage, determining the vegetation growth rate of the monitoring area according to the vegetation coverage and the area of ​​the monitoring area includes:

[0030] Determine the vegetation growth width of the monitoring area according to the vegetation coverage and the area of ​​the monitoring area;

[0031] The vegetation growth rate of the monitoring area is determined according to the vegetation growth width.

[0032] Preferably, the vegetation growth width is determined according to the following formula:

[0033]

[0034] Among them, Bt represents the width of vegetation growth at time point t, S0 represents the area of ​​the monitoring area, and C t represents the vegetation coverage at time point t, C t-1 Indicates the vegetation coverage at time point t-1.

[0035] Preferably, the vegetation growth rate is determined according to the following formula:

[0036] Vt=a·Bt;

[0037] Among them, Vt represents the vegetation growth rate at time point t, a represents the growth rate coefficient, and Bt represents the vegetation growth width at time point t.

[0038] Preferably, determining the vegetation growth assessment level of the monitoring area according to the vegetation growth rate includes:

[0039] A first preset growth rate, a second preset growth rate and a third preset growth rate are set, and the first preset growth rate, the second preset growth rate and the third preset growth rate increase in sequence;

[0040] Determining a vegetation growth assessment level of the monitoring area according to a relationship between the vegetation growth rate and the first preset growth rate, the second preset growth rate, and the third preset growth rate;

[0041] If the vegetation growth rate is less than the first preset growth rate, determining the vegetation growth assessment level of the monitoring area to be the first growth assessment level L1;

[0042] If the vegetation growth rate is greater than or equal to the first preset growth rate, and the vegetation growth rate is less than the second preset growth rate, determining that the vegetation growth assessment level of the monitoring area is the second growth assessment level L2;

[0043] If the vegetation growth rate is greater than or equal to the second preset growth rate, and the vegetation growth rate is less than the third preset growth rate, then determining that the vegetation growth assessment level of the monitoring area is the third growth assessment level L3;

[0044] If the vegetation growth rate is greater than or equal to the third preset growth rate, the vegetation growth assessment level of the monitoring area is determined to be a fourth growth assessment level L4, wherein L1<L2<L3<L4.

[0045] The present invention also discloses a vegetation growth assessment system based on remote sensing technology, which is used to apply the above-mentioned vegetation growth assessment method based on remote sensing technology, and comprises:

[0046] An image acquisition module is used to acquire real-time remote sensing images of the monitoring area;

[0047] A change rate determination module, used to process the real-time remote sensing image to obtain remote sensing data of the real-time remote sensing image, and determine the normalized vegetation index of the monitoring area according to the remote sensing data; and determine the vegetation coverage of the monitoring area according to the normalized vegetation index, and determine the vegetation coverage change rate of the monitoring area according to the vegetation coverage;

[0048] A growth stage determination module, used for comparing the vegetation coverage change rate with a preset coverage change rate, and determining the growth stage of the vegetation according to the comparison result, wherein the growth stage includes a non-influence growth stage and a mutual influence growth stage;

[0049] A growth assessment module is used to determine the vegetation growth assessment level of the monitoring area according to the vegetation coverage change rate when the growth stage is the non-influence growth stage; when the growth stage is the mutual influence growth stage, determine the vegetation growth rate of the monitoring area according to the vegetation coverage and the area of ​​the monitoring area, and determine the vegetation growth assessment level of the monitoring area according to the vegetation growth rate.

[0050] Compared with the prior art, the invention has the beneficial effect that the invention improves the accuracy and efficiency of vegetation growth assessment. By acquiring remote sensing images in real time and processing remote sensing data, the growth status of vegetation can be quickly and accurately assessed without tedious ground surveys. And the accurate division of vegetation growth stages is achieved. By calculating the normalized vegetation index and the vegetation coverage change rate, the vegetation's unaffected growth stage and the mutually-affected growth stage can be distinguished, thereby providing more detailed guidance for vegetation management. The determination method of the vegetation growth assessment level is optimized. According to the vegetation coverage change rate and the vegetation growth rate, the vegetation growth assessment level can be determined more scientifically, providing a more accurate reference basis for decision makers. The rational allocation and utilization of resources are promoted. By monitoring the vegetation growth status, vegetation growth problems can be discovered in time, resources can be rationally planned, vegetation degradation can be effectively prevented and controlled, and the ecological environment can be protected. The monitoring capability of dynamic changes in vegetation growth is enhanced. The invention can continuously track the vegetation coverage change rate, discover abnormal conditions of vegetation growth in time, and provide dynamic data support for vegetation protection and restoration. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0052] Figure 1 It is a flow chart of a vegetation growth assessment method based on remote sensing technology of the present invention.

[0053] Figure 2 It is a functional block diagram of a vegetation growth assessment system based on remote sensing technology of the present invention. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0055] like Figure 1 As shown, the present invention provides a vegetation growth assessment method based on remote sensing technology, comprising:

[0056] Obtain real-time remote sensing images of the monitoring area.

[0057] The real-time remote sensing image is processed to obtain remote sensing data of the real-time remote sensing image, and the normalized vegetation index of the monitoring area is determined based on the remote sensing data.

[0058] The vegetation coverage of the monitoring area is determined according to the normalized difference vegetation index, and the vegetation coverage change rate of the monitoring area is determined according to the vegetation coverage.

[0059] The vegetation coverage change rate is compared with the preset coverage change rate, and the growth stage of the vegetation is determined according to the comparison result. The growth stage includes the no-impact growth stage and the mutual-impact growth stage.

[0060] When the growth stage is the no-impact growth stage, the vegetation growth assessment level of the monitored area is determined according to the vegetation coverage change rate.

[0061] When the growth stage is the mutually influencing growth stage, the vegetation growth rate of the monitoring area is determined according to the vegetation coverage and the area of ​​the monitoring area, and the vegetation growth assessment level of the monitoring area is determined according to the vegetation growth rate.

[0062] In some embodiments of the present application, when determining the normalized vegetation index of the monitoring area according to remote sensing data, the normalized vegetation index is determined according to the following formula:

[0063]

[0064] Among them, NDVI represents the normalized difference vegetation index, p(NIR) represents the near-infrared band reflectance, and p(R) represents the red band reflectance.

[0065] In this embodiment, when processing real-time remote sensing images, a series of image preprocessing steps, such as radiation correction and atmospheric correction, are required to eliminate errors that may be introduced during image acquisition. Next, the image processing algorithm is used to extract useful information from the remote sensing image to obtain remote sensing data. These data may include reflectivity and brightness values ​​of different bands. After obtaining the remote sensing data, the normalized vegetation index NDVI of the monitored area can be further calculated.

[0066] In some embodiments of the present application, the vegetation coverage of the monitoring area is determined according to the normalized vegetation index, including: selecting 5% of the cumulative frequency of the normalized vegetation index in the monitoring area as the normalized vegetation index of non-vegetation pixels, and selecting 95% of the cumulative frequency of the normalized vegetation index in the monitoring area as the normalized vegetation index of vegetation pixels; determining the vegetation coverage of the monitoring area according to the normalized vegetation index, the normalized vegetation index of non-vegetation pixels, and the normalized vegetation index of vegetation pixels;

[0067] Vegetation coverage is determined according to the following formula:

[0068]

[0069] Among them, FVC represents vegetation coverage, NDVI soi l Represents the normalized difference vegetation index of non-vegetated pixels, NDVI veg Represents the normalized difference vegetation index of vegetation pixels.

[0070] In this embodiment, the steps of determining the vegetation coverage of the monitoring area are as follows: collect the normalized vegetation index (NDVI) data of the monitoring area. Sort the collected NDVI data and calculate the cumulative frequency distribution. Select the NDVI value with a cumulative frequency of 5% as the NDVI threshold of non-vegetation pixels. This threshold represents the 5% of pixels with the lowest vegetation coverage in the monitoring area, and these pixels are usually considered to be bare land or non-vegetation areas. Select the NDVI value with a cumulative frequency of 95% as the NDVI threshold of vegetation pixels. This threshold represents the 95% of pixels with the highest vegetation coverage in the monitoring area, and these pixels are usually considered to be densely vegetated areas. Using the NDVI threshold of non-vegetation pixels and the NDVI threshold of vegetation pixels, combined with actual NDVI data, the vegetation coverage of the entire monitoring area is calculated through a certain algorithm, such as a pixel dichotomy model. Vegetation coverage refers to the proportion of vegetation on the surface, usually expressed as a percentage. According to the calculation results, the vegetation condition of the monitoring area can be evaluated and monitored, providing a scientific basis for vegetation protection, ecological management, etc.

[0071] In some embodiments of the present application, the vegetation coverage change rate is compared with a preset coverage change rate, and the growth stage of the vegetation is determined based on the comparison result, including: comparing the vegetation coverage change rate with the preset coverage change rate in chronological order, when the vegetation coverage change rate is less than the preset coverage change rate for the second time, determining the corresponding time point as the demarcation time point, determining the time period before the demarcation time point as the unaffected growth stage, and determining the time period after the demarcation time point as the mutually influential growth stage.

[0072] In order to accurately monitor the growth of vegetation, the growth stage of vegetation can be determined by analyzing the relationship between the vegetation coverage change rate and the preset coverage change rate. The vegetation coverage change rate refers to the change in vegetation coverage per unit time, usually expressed as a percentage. The details are as follows: First, set a preset coverage change rate, which can be determined based on historical data, expert experience or a specific growth model. Then, compare the actual measured vegetation coverage change rate with the preset coverage change rate. The comparison needs to be carried out in chronological order, that is, starting from the early stage of vegetation growth, and comparing each time point. During the comparison process, find the time point when the vegetation coverage change rate is less than the preset coverage change rate for the second time. This time point is the demarcation time point, which indicates that the area between adjacent vegetation has been completely covered. When this demarcation time point is found, the time period before this time point is defined as the unaffected growth stage. At this stage, the growth of vegetation is mainly affected by its own environment and internal factors, such as seed germination, seedling growth, etc., and the vegetation is fully illuminated at this stage. The time period after the demarcation time point is determined as the mutually influential growth stage. At this stage, the growth of vegetation is not only affected by internal factors, but also by external vegetation. For example, when the vegetation grows too lush, adjacent vegetation will block the sunlight.

[0073] In some embodiments of the present application, when the growth stage is a non-impact growth stage, the vegetation growth assessment level of the monitoring area is determined according to the vegetation coverage change rate, including: setting a first preset change rate, a second preset change rate and a third preset change rate, and the first preset change rate, the second preset change rate and the third preset change rate increase in sequence; determining the vegetation growth assessment level of the monitoring area according to the relationship between the vegetation coverage change rate and the first preset change rate, the second preset change rate and the third preset change rate; if the vegetation coverage change rate is less than the first preset change rate, determining the vegetation growth assessment level of the monitoring area as the first growth assessment level. Level L1; if the vegetation coverage change rate is greater than or equal to the first preset change rate, and the vegetation coverage change rate is less than the second preset change rate, the vegetation growth assessment level of the monitoring area is determined to be the second growth assessment level L2; if the vegetation coverage change rate is greater than or equal to the second preset change rate, and the vegetation coverage change rate is less than the third preset change rate, the vegetation growth assessment level of the monitoring area is determined to be the third growth assessment level L3; if the vegetation coverage change rate is greater than or equal to the third preset change rate, the vegetation growth assessment level of the monitoring area is determined to be the fourth growth assessment level L4; wherein, L1<L2<L3<L4.

[0074] In this embodiment, by setting different preset change rates, the growth status of vegetation can be evaluated more accurately, thereby monitoring vegetation growth more carefully. By comparing the vegetation coverage change rate with the preset change rate, it is possible to quickly identify whether vegetation growth is abnormal and take timely measures. According to different growth assessment levels, corresponding vegetation management measures can be formulated or adjusted to promote the healthy growth of vegetation. After clarifying the vegetation growth status, resources and manpower can be allocated more reasonably, and different management strategies can be adopted for areas with different growth levels.

[0075] In some embodiments of the present application, when the growth stage is a mutually influencing growth stage, the vegetation growth rate of the monitoring area is determined based on the vegetation coverage and the area of ​​the monitoring area, including: determining the vegetation growth width of the monitoring area based on the vegetation coverage and the area of ​​the monitoring area; determining the vegetation growth rate of the monitoring area based on the vegetation growth width.

[0076] In the interactive growth stage, the growth of vegetation is not only controlled by its own genetic characteristics, but also by the interaction with surrounding vegetation. In order to accurately assess the vegetation growth rate in this stage, it is necessary to consider the vegetation coverage and the area of ​​the monitoring area. Combining the vegetation coverage with the total area of ​​the monitoring area, the width of vegetation growth can be calculated, that is, the horizontal expansion range of vegetation.

[0077] In the mutually influencing growth stage, even if the adjacent areas inside the vegetation grow, it will have little impact on the vegetation coverage. However, the growth of the vegetation edge area will increase the vegetation coverage. Therefore, the vegetation growth width and vegetation growth rate are determined by the vegetation coverage and the area of ​​the monitoring area.

[0078] In some embodiments of the present application, the vegetation growth width is determined according to the following formula:

[0079]

[0080] Among them, Bt represents the width of vegetation growth at time point t, S0 represents the area of ​​the monitoring area, and C t represents the vegetation coverage at time point t, C t-1 Indicates the vegetation coverage at time point t-1.

[0081] In some embodiments of the present application, the vegetation growth rate is determined according to the following formula: Vt=a·Bt; wherein Vt represents the vegetation growth rate at time point t, a represents the growth rate coefficient, and Bt represents the vegetation growth width at time point t.

[0082] In some embodiments of the present application, determining the vegetation growth assessment level of the monitoring area according to the vegetation growth rate includes: setting a first preset growth rate, a second preset growth rate and a third preset growth rate, and the first preset growth rate, the second preset growth rate and the third preset growth rate increase in sequence; determining the vegetation growth assessment level of the monitoring area according to the relationship between the vegetation growth rate and the first preset growth rate, the second preset growth rate and the third preset growth rate; if the vegetation growth rate is less than the first preset growth rate, determining the vegetation growth assessment level of the monitoring area as the first growth assessment level L1; if the vegetation growth rate is greater than or equal to the first preset growth rate, and the vegetation growth rate is less than the second preset growth rate, determining the vegetation growth assessment level of the monitoring area as the second growth assessment level L2; if the vegetation growth rate is greater than or equal to the second preset growth rate, and the vegetation growth rate is less than the third preset growth rate, determining the vegetation growth assessment level of the monitoring area as the third growth assessment level L3; if the vegetation growth rate is greater than or equal to the third preset growth rate, determining the vegetation growth assessment level of the monitoring area as the fourth growth assessment level L4, wherein L1<L2<L3<L4.

[0083] In this embodiment, the present application can divide the vegetation growth conditions more finely by setting multiple preset growth rates, thereby providing a more accurate growth assessment level. The vegetation growth rate is a dynamically changing indicator. The scheme can dynamically adjust the vegetation growth assessment level according to real-time monitoring data to timely reflect the vegetation growth status. By dividing the assessment levels, corresponding management measures and resource allocation can be formulated for areas with different growth conditions to optimize resource utilization efficiency.

[0084] The present invention also discloses a vegetation growth assessment system based on remote sensing technology, which is used to apply the above-mentioned vegetation growth assessment method based on remote sensing technology, such as Figure 2 As shown, including:

[0085] The image acquisition module is used to obtain real-time remote sensing images of the monitoring area.

[0086] The change rate determination module is used to process the real-time remote sensing image to obtain the remote sensing data of the real-time remote sensing image, and determine the normalized vegetation index of the monitoring area according to the remote sensing data; and determine the vegetation coverage of the monitoring area according to the normalized vegetation index, and determine the vegetation coverage change rate of the monitoring area according to the vegetation coverage.

[0087] The growth stage determination module is used to compare the vegetation coverage change rate with the preset coverage change rate, and determine the growth stage of the vegetation according to the comparison result. The growth stage includes the no-influence growth stage and the mutual-influence growth stage.

[0088] The growth assessment module is used to determine the vegetation growth assessment level of the monitored area according to the vegetation coverage change rate when the growth stage is the non-impact growth stage; when the growth stage is the mutual influence growth stage, the vegetation growth rate of the monitored area is determined according to the vegetation coverage and the area of ​​the monitored area, and the vegetation growth assessment level of the monitored area is determined according to the vegetation growth rate.

[0089] The present invention uses an image acquisition module, and the system can acquire remote sensing images of the monitoring area in real time, thereby realizing continuous tracking and monitoring of vegetation growth conditions. The change rate determination module can process remote sensing images, accurately calculate the normalized vegetation index and vegetation coverage change rate of vegetation, and provide accurate quantitative indicators for vegetation growth conditions. The growth stage determination module can effectively identify the growth stage of vegetation according to the comparison of the vegetation coverage change rate with the preset standard, distinguish the growth stage without influence and the growth stage with mutual influence, and provide an important basis for subsequent growth evaluation. The growth evaluation module can dynamically evaluate the growth level of vegetation according to the vegetation coverage change rate or the vegetation growth rate, and provide a scientific basis for agricultural management, ecological protection, etc. The whole system can quickly respond to changes in vegetation growth conditions, provide timely information support for decision makers, and improve decision-making efficiency and accuracy. And by accurately evaluating the vegetation growth conditions, it is helpful to rationally plan land resources and agricultural resources, and realize the optimal allocation and sustainable development of resources.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

[0091] The system provided in the above embodiment is only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the modules or steps in the embodiments of the present invention can be decomposed or combined. For example, the modules in the above embodiment can be combined into one module, or further divided into multiple sub-modules to complete all or part of the functions described above. The names of the modules and steps involved in the embodiments of the present invention are only for distinguishing the modules or steps, and are not regarded as improper limitations of the present invention.

[0092] Those skilled in the art should be able to appreciate that the modules and method steps of each example described in conjunction with the embodiments disclosed herein can be implemented with electronic hardware, computer software or a combination of the two, and the programs corresponding to the software modules and method steps can be placed in random access memory (RAM), memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disks, removable disks, CD-ROMs or any other form of storage medium known in the technical field. In order to clearly illustrate the interchangeability of electronic hardware and software, the composition and steps of each example have been generally described in the above description according to the function. Whether these functions are performed in electronic hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

Claims

1. A vegetation growth assessment method based on remote sensing technology, characterized in that: The method comprises: Obtain real-time remote sensing images of the monitoring area; Processing the real-time remote sensing image to obtain remote sensing data of the real-time remote sensing image, and determining a normalized vegetation index of the monitoring area according to the remote sensing data; Determining the vegetation coverage of the monitoring area according to the normalized vegetation index, and determining the vegetation coverage change rate of the monitoring area according to the vegetation coverage; Comparing the vegetation coverage change rate with a preset coverage change rate, and determining the growth stage of the vegetation according to the comparison result, wherein the growth stage includes a non-influence growth stage and a mutual influence growth stage; When the growth stage is a non-impact growth stage, determining the vegetation growth assessment level of the monitoring area according to the vegetation coverage change rate; When the growth stage is a mutually influencing growth stage, the vegetation growth rate of the monitoring area is determined according to the vegetation coverage and the area of ​​the monitoring area, and the vegetation growth assessment level of the monitoring area is determined according to the vegetation growth rate.

2. The vegetation growth assessment method based on remote sensing technology according to claim 1, characterized in that: When determining the normalized vegetation index of the monitoring area according to the remote sensing data, the normalized vegetation index is determined according to the following formula: Among them, NDVI represents the normalized difference vegetation index, p(NIR) represents the near-infrared band reflectance, and p(R) represents the red band reflectance.

3. The vegetation growth assessment method based on remote sensing technology according to claim 2, characterized in that: Determining the vegetation coverage of the monitoring area according to the normalized difference vegetation index includes: 5% of the cumulative frequency of the NDVI in the monitoring area is selected as the NDVI of non-vegetated pixels, and 95% of the cumulative frequency of the NDVI in the monitoring area is selected as the NDVI of vegetation pixels; Determining the vegetation coverage of the monitoring area according to the normalized vegetation index, the normalized vegetation index of non-vegetation pixels and the normalized vegetation index of vegetation pixels; The vegetation coverage is determined according to the following formula: Among them, FVC represents vegetation coverage, NDVI soil Represents the normalized difference vegetation index of non-vegetated pixels, NDVI veg Represents the normalized difference vegetation index of vegetation pixels.

4. The vegetation growth assessment method based on remote sensing technology according to claim 1, characterized in that: The vegetation coverage change rate is compared with a preset coverage change rate, and the growth stage of the vegetation is determined according to the comparison result, including: The vegetation coverage change rate is compared with the preset coverage change rate in chronological order. When the vegetation coverage change rate is less than the preset coverage change rate for the second time, the corresponding time point is determined as the demarcation time point, the time period before the demarcation time point is determined as the uninfluenced growth stage, and the time period after the demarcation time point is determined as the mutually influencing growth stage.

5. The vegetation growth assessment method based on remote sensing technology according to claim 1, characterized in that: When the growth stage is the non-impact growth stage, the vegetation growth assessment level of the monitoring area is determined according to the vegetation coverage change rate, including: A first preset change rate, a second preset change rate and a third preset change rate are set, and the first preset change rate, the second preset change rate and the third preset change rate increase in sequence; Determining a vegetation growth assessment level of the monitoring area according to a relationship between the vegetation coverage change rate and the first preset change rate, the second preset change rate, and the third preset change rate; If the vegetation coverage change rate is less than the first preset change rate, determining the vegetation growth assessment level of the monitoring area to be the first growth assessment level L1; If the vegetation coverage change rate is greater than or equal to the first preset change rate, and the vegetation coverage change rate is less than the second preset change rate, then determining that the vegetation growth assessment level of the monitoring area is the second growth assessment level L2; If the vegetation coverage change rate is greater than or equal to the second preset change rate, and the vegetation coverage change rate is less than the third preset change rate, then determining that the vegetation growth assessment level of the monitoring area is the third growth assessment level L3; If the vegetation coverage change rate is greater than or equal to the third preset change rate, the vegetation growth assessment level of the monitored area is determined to be the fourth growth assessment level L4; wherein L1<L2<L3<L4.

6. The vegetation growth assessment method based on remote sensing technology according to claim 5, characterized in that: When the growth stage is a mutually influencing growth stage, determining the vegetation growth rate of the monitoring area according to the vegetation coverage and the area of ​​the monitoring area includes: Determine the vegetation growth width of the monitoring area according to the vegetation coverage and the area of ​​the monitoring area; The vegetation growth rate of the monitoring area is determined according to the vegetation growth width.

7. The vegetation growth assessment method based on remote sensing technology according to claim 6, characterized in that: The vegetation growth width is determined according to the following formula: Among them, Bt represents the vegetation growth width at time point t, S0 represents the area of ​​the monitoring area, and C t represents the vegetation coverage at time point t, C t-1 Indicates the vegetation coverage at time point t-1.

8. The vegetation growth assessment method based on remote sensing technology according to claim 7, characterized in that: The vegetation growth rate is determined according to the following formula: Vt=a·Bt; Among them, Vt represents the vegetation growth rate at time point t, a represents the growth rate coefficient, and Bt represents the vegetation growth width at time point t.

9. The vegetation growth assessment method based on remote sensing technology according to claim 8, characterized in that: The vegetation growth assessment level of the monitoring area is determined according to the vegetation growth rate, including: A first preset growth rate, a second preset growth rate and a third preset growth rate are set, and the first preset growth rate, the second preset growth rate and the third preset growth rate increase in sequence; Determining a vegetation growth assessment level of the monitoring area according to a relationship between the vegetation growth rate and the first preset growth rate, the second preset growth rate, and the third preset growth rate; If the vegetation growth rate is less than the first preset growth rate, determining the vegetation growth assessment level of the monitoring area to be the first growth assessment level L1; If the vegetation growth rate is greater than or equal to the first preset growth rate, and the vegetation growth rate is less than the second preset growth rate, determining that the vegetation growth assessment level of the monitoring area is the second growth assessment level L2; If the vegetation growth rate is greater than or equal to the second preset growth rate, and the vegetation growth rate is less than the third preset growth rate, then determining that the vegetation growth assessment level of the monitoring area is the third growth assessment level L3; If the vegetation growth rate is greater than or equal to the third preset growth rate, the vegetation growth assessment level of the monitoring area is determined to be a fourth growth assessment level L4, wherein L1<L2<L3<L4.

10. A vegetation growth assessment system based on remote sensing technology, used for applying the vegetation growth assessment method based on remote sensing technology as claimed in any one of claims 1 to 9, characterized in that: The system comprises: An image acquisition module is used to acquire real-time remote sensing images of the monitoring area; A change rate determination module, used to process the real-time remote sensing image to obtain remote sensing data of the real-time remote sensing image, and determine the normalized vegetation index of the monitoring area according to the remote sensing data; and determine the vegetation coverage of the monitoring area according to the normalized vegetation index, and determine the vegetation coverage change rate of the monitoring area according to the vegetation coverage; A growth stage determination module, used for comparing the vegetation coverage change rate with a preset coverage change rate, and determining the growth stage of the vegetation according to the comparison result, wherein the growth stage includes a non-influence growth stage and a mutual influence growth stage; A growth assessment module is used to determine the vegetation growth assessment level of the monitoring area according to the vegetation coverage change rate when the growth stage is the non-influence growth stage; when the growth stage is the mutual influence growth stage, determine the vegetation growth rate of the monitoring area according to the vegetation coverage and the area of ​​the monitoring area, and determine the vegetation growth assessment level of the monitoring area according to the vegetation growth rate.

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