A method for evaluating the greening rate of a slope ecological project

Abstract

The present invention relates to the technical field of slope greening perception, and discloses a method for evaluating the greening rate of slope ecological engineering, including obtaining the digital elevation map and orthophoto of the slope; based on the orthophoto, dividing the slope into vegetation-covered areas and non-vegetation-covered areas according to the visible light difference vegetation index; according to the digital elevation map of the vegetation-covered area, calculating the overall slope greening rate and the slope greening rates of different slope intervals by using the slope division method; according to the digital elevation map of the vegetation-covered area, calculating the slope green view rate at different observation positions and the average slope green view rate by using the observation point view analysis method. By establishing the overall slope greening rate describing the ecological functionality of the slope surface, the slope greening rates of different slope intervals, the slope green view rate at specific observation positions for evaluating the landscape functionality, and the average green view rate for evaluating the overall landscape functionality, the present invention can achieve a more comprehensive and accurate slope greening evaluation effect.

Description

Technical Field

[0001] The present invention relates to the technical field of slope greening perception, and particularly relates to a method for evaluating the greening rate of slope ecological engineering. Background Art

[0002] The ecological engineering of road slopes and mine slopes is an important part of the construction of ecological civilization and is of great significance for beautifying the ecological environment. At present, the lack of a clear evaluation method for the greening effect of slope ecological engineering restricts the economic design, effect monitoring and acceptance of ecological engineering. Traditional evaluation of greening effect mostly uses the greening rate of projected area as the evaluation index, that is, the ratio of the projected area of the vegetation area on the horizontal plane to the total projected area. However, the greening rate index of projected area seriously ignores the slope effect and the field of view problem of the slope. The slope effect means that for the same projected area, the slope areas with different slopes are not the same, and the steeper the slope, the larger the slope area; the field of view problem means that the near-view objects or terrain occlusion form a blind area of vision, and the ground objects in the far view cannot be observed. Therefore, the evaluation result of the greening rate of projected area without considering the slope effect and the field of view problem overestimates both the true greening situation of the slope and the greening effect in human eye perception, and cannot objectively evaluate the functional and landscape characteristics of slope ecological engineering.

[0003] To objectively describe the degree of slope greening and the human perception of greening, and at the same time clarify the problems existing in the current slope greening, it is of great significance to introduce the slope greening rate, the greening rate in different slope intervals, and the green view rate at different observation distances into the evaluation of slope greening effect. The slope greening rate can reflect the area of the growth of real plants and can better reflect the functional characteristics of the ecosystem than the projected greening rate. At the same time, the green view rate can more accurately reflect the human perception and can better evaluate the landscape characteristics of the revegetation project.

[0004] At present, the measurement of the slope greening rate often adopts traditional measurement or estimation based on slope characteristics, while the calculation of the green view rate often adopts on-site photography and image processing. The measurement of these two parameters is time-consuming, laborious and costly, and cannot comprehensively and accurately describe the results, let alone show the greening characteristics of different slopes and the observation results at different observation angles and distances. Summary of the Invention

[0005] In view of the above deficiencies in the prior art, the present invention provides a method for evaluating the greening rate of slope ecological engineering.

[0006] In order to achieve the above invention purpose, the technical solution adopted by the present invention is as follows:

[0007] A method for evaluating the greening rate of slope ecological engineering includes the following steps:

[0008] Obtain the digital elevation map and orthophoto of the slope;

[0009] Based on the orthophoto image, the slope is divided into a vegetated area and a non-vegetated area according to the visible light difference vegetation index;

[0010] Based on the digital elevation map of the vegetated area, the overall slope greening rate and the slope greening rates of different slope intervals are calculated using the slope division method;

[0011] Based on the digital elevation map of the vegetated area, the slope green view rate and the average slope green view rate at different observation positions are calculated using the observation point view analysis method.

[0012] Optionally, based on the orthophoto image, the slope is divided into a vegetated area and a non-vegetated area according to the visible light difference vegetation index, including:

[0013] The visible light difference vegetation index is calculated based on the orthophoto image, expressed as:

[0014]

[0015] where, represents the visible light difference vegetation index, represents the green band, red band, and blue band of the RGB image, represents the position serial number in the horizontal and vertical directions of the raster file;

[0016] The slopes with a visible light difference vegetation index greater than the set threshold are divided into the vegetated area, and the slopes with a visible light difference vegetation index less than or equal to the set threshold are divided into the non-vegetated area.

[0017] Optionally, based on the digital elevation map of the vegetated area, the overall slope greening rate and the slope greening rates of different slope intervals are calculated using the slope division method, including:

[0018] The digital elevation map of the vegetated area is divided into grids to calculate the overall slope greening rate;

[0019] The digital elevation map of the vegetated area is divided by slope to calculate the slope greening rates of different slope intervals.

[0020] Optionally, the digital elevation map of the vegetated area is divided into grids to calculate the overall slope greening rate, including:

[0021] The digital elevation map of the vegetated area is divided into grids to calculate the slope value corresponding to each grid;

[0022] According to the slope values corresponding to each grid, the slope area values corresponding to each grid are calculated;

[0023] After performing matrix processing on the slope area values and vegetation coverage area determination values corresponding to each grid and then performing Hadamard multiplication operation, the slope area value of the vegetation coverage area is obtained;

[0024] According to the slope area value of the vegetation coverage area and the slope area values corresponding to each grid, the overall slope greening rate is calculated.

[0025] Optionally, the calculation method of the overall slope greening rate is:

[0026]

[0027] where, represents the overall slope greening rate, represents the slope area value of the vegetation coverage area, represents the slope area value, represents the position serial number in the horizontal and vertical directions of the grid file.

[0028] Optionally, the digital elevation map of the vegetation coverage area is divided by slope, and the slope greening rates in different slope intervals are calculated, including:

[0029] The digital elevation map of the vegetation coverage area is divided into multiple slope intervals according to the set slope interval;

[0030] Calculate the slope area values corresponding to each slope interval;

[0031] After performing matrix processing on the slope area values corresponding to each slope interval and the vegetation coverage area determination values and then performing Hadamard multiplication operation, the slope area values of the vegetation coverage area under each slope interval are obtained;

[0032] According to the slope area values of the vegetation coverage area under each slope interval and the slope area values corresponding to each slope interval, the slope greening rates of each slope interval are calculated.

[0033] Optionally, the calculation method of the slope greening rate of each slope interval is:

[0034]

[0035] where, represents the slope greening rate, represents the slope area value of the vegetation coverage area, represents the slope area value, represents the position serial number in the horizontal and vertical directions of the grid file, represents the slope interval serial number.

[0036] Optionally, according to the digital elevation map of the vegetation-covered area, the view factor analysis method is used to calculate the slope green view rate and the average slope green view rate at different observation positions, including:

[0037] Set up observation points in the observation area and determine the positions of the observation points according to the digital elevation map of the vegetation-covered area;

[0038] Perform view factor analysis on each observation point one by one to obtain the slope view factor results;

[0039] Calculate the slope perceived area value according to the pitch angle and the ratio of distance and size of the line of sight of the observation point;

[0040] Perform matrix processing on the slope perceived area value and the slope view factor results and then perform Hadamard multiplication operation to obtain the perceived area value within the view factor range;

[0041] Perform matrix processing on the perceived area value within the view factor range and the vegetation coverage area determination value and then perform Hadamard multiplication operation to obtain the vegetation perceived area value within the view factor range;

[0042] Calculate the slope green view rate at different observation positions according to the perceived area value within the view factor range and the vegetation perceived area value within the view factor range;

[0043] After removing abnormal data from the slope green view rates at different observation positions, calculate the average green view rate to obtain the average slope green view rate.

[0044] Optionally, the calculation method of the slope perceived area value is:

[0045]

[0046] Wherein, represents the slope perceived area value, represents the slope value, represents the size of the grid cell, represents the observation point iii and the position to be observed the distance between them, represents the pitch angle.

[0047] Optionally, the calculation method of the slope green view rate at different observation positions is:

[0048]

[0049] Wherein, represents the slope green view rate of the observation point iii , represents the vegetation perceived area value within the view factor range, represents the perceived area value within the view factor range, Indicates the position serial numbers in the horizontal and vertical directions of the raster file.

[0050] The present invention has the following beneficial effects:

[0051] By establishing the overall slope greening rate describing the ecological functionality of the slope surface, the slope greening rate in different slope intervals, the slope green view rate at specific observation positions for evaluating landscape functionality, and the average green view rate for evaluating the overall landscape functionality, the present invention can achieve a more comprehensive and accurate evaluation effect of slope greening. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a schematic flow diagram of a method for evaluating the greening rate of a slope ecological project;

[0053] Figure 2 It is a schematic diagram of the segmentation of the vegetation-covered area and the non-vegetation-covered area;

[0054] Figure 3 It is a schematic diagram of slope calculation, slope area calculation, and slope classification;

[0055] Figure 4 It is a schematic diagram of the layout of observation points;

[0056] Figure 5 It is a schematic diagram of the slope view result;

[0057] Figure 6 It is a schematic diagram of the calculation of the slope perceived area value. DETAILED DESCRIPTION OF THE INVENTION

[0058] The following describes the specific embodiments of the present invention to facilitate those skilled in the art to understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention defined and determined by the appended claims, these changes are obvious, and all inventions and creations using the concept of the present invention are within the scope of protection.

[0059] Aiming at the technical problem that the prior art lacks rapid evaluation indicators and evaluation methods for the greening effect of ecological projects facing complex slope terrains, the present invention proposes a rapid evaluation method for the functional and landscape greening effects of slope ecological projects, and proposes a corresponding low-cost automated extraction method, which can be used for the acceptance and monitoring of revegetation projects. Specifically as follows:

[0060] (a) Aiming at the problem of the lack of a method for evaluating the greening effect of slopes, the present invention proposes a technical method of low-altitude UAV shooting and modeling, calculation of the slope greening rate, and calculation of the green view rate at different custom observation positions.

[0061] (b)Regarding the current use of the greening rate of the projected area, this study proposes an evaluation method for the slope greening rate and the greening rate in different slope intervals, which can evaluate the greening effect more comprehensively and accurately.

[0062] (c)Compared with the current green view rate evaluation method using fixed-point photography, the method proposed by the present invention can, after one survey and modeling, evaluate the green view rate at a custom location.

[0063] (d)Compared with using expensive mobile three-dimensional laser scanning instruments, the present invention uses unmanned aerial vehicle (UAV) photography and modeling, which can solve the problems of high cost and limited shooting angles.

[0064] (e)Compared with the complex recognition models used in the existing green view rate analysis, since the ecological structure of the slope revegetation project is often simple and the difference between the vegetation and non-vegetation areas is significant, the present invention uses the visible difference vegetation index to divide the slope plant area.

[0065] As Figure 1 shown, a method for evaluating the greening rate of a slope ecological project provided by an embodiment of the present invention includes the following steps S1 to S4:

[0066] S1. Obtain the digital elevation map and orthophoto of the slope;

[0067] In an optional embodiment of the present invention, in step S1, the slope to be evaluated is photographed by a UAV to obtain the digital elevation map and orthophoto of the slope to be evaluated with a specified resolution.

[0068] In step S1, a low-altitude flight is performed above the slope (the distance from the slope surface is less than 30 m), the established high-precision digital elevation map and orthophoto are cropped using the range of the slope to be evaluated, and the result is resampled based on the average vegetation crown diameter size d of the slope. The resampling technical method uses bilinear interpolation.

[0069] S2. Based on the orthophoto, divide the slope into a vegetation-covered area and a non-vegetation-covered area according to the visible difference vegetation index;

[0070] In an optional embodiment of the present invention, in step S2, based on the orthophoto, dividing the slope into a vegetation-covered area and a non-vegetation-covered area according to the visible difference vegetation index includes:

[0071] Calculate the visible difference vegetation index according to the orthophoto, expressed as:

[0072]

[0073] where represents the visible difference vegetation index, represents the green band, red band, and blue band of the RGB image, Indicates the position serial numbers in the horizontal and vertical directions of the raster file;

[0074] Slopes with visible difference vegetation index greater than the set threshold are classified as vegetation-covered areas, and slopes with visible difference vegetation index less than or equal to the set threshold are classified as non-vegetation-covered areas, expressed as:

[0075]

[0076] Among them, Indicates the determination value of the vegetation-covered area.

[0077] In this embodiment, based on the significant difference between the greening area and the non-greening area in the slope revegetation project, the visible difference vegetation index (VDVI) is used as the classification index, and the threshold classification is defaulted to 0.1, that is, above 0.1 is the vegetation area, and below 0.1 is the non-vegetation area, as Figure 2 shown.

[0078] S3. According to the digital elevation map of the vegetation-covered area, use the slope division method to calculate the overall slope greening rate and the slope greening rates of different slope intervals;

[0079] In an alternative embodiment of the present invention, step S3 calculates the overall slope greening rate and the slope greening rates of different slope intervals according to the digital elevation map of the vegetation-covered area, including:

[0080] Perform grid division on the digital elevation map of the vegetation-covered area and calculate the overall slope greening rate;

[0081] Perform slope division on the digital elevation map of the vegetation-covered area and calculate the slope greening rates of different slope intervals.

[0082] In this embodiment, perform grid division on the digital elevation map of the vegetation-covered area and calculate the overall slope greening rate, as Figure 3 shown, including:

[0083] Perform grid division on the digital elevation map of the vegetation-covered area and calculate the slope values corresponding to each grid, expressed as:

[0084]

[0085]

[0086]

[0087] Among them, dem represents the raster cell, dzdx represents the slope in the x direction, dzdy represents the slope in the y direction, respectively represent the position serial numbers in the horizontal and vertical directions of the raster cell; Indicates the slope value corresponding to the i th grid cell in the horizontal direction and the j th grid cell in the vertical direction;

[0088] According to the slope values corresponding to each grid, calculate the slope surface area values corresponding to each grid, expressed as:

[0089]

[0090] Wherein, represents;

[0091] After performing matrix processing on the slope surface area values and vegetation coverage area determination values corresponding to each grid, perform Hadamard multiplication operation to obtain the slope surface area value of the vegetation coverage area, expressed as:

[0092]

[0093] According to the slope surface area value of the vegetation coverage area and the slope surface area values corresponding to each grid, calculate the overall slope surface greening rate, expressed as:

[0094]

[0095] Wherein, represents the overall slope surface greening rate, represents the slope surface area value of the vegetation coverage area, represents the slope surface area value, represents the position serial number in the horizontal and vertical directions of the grid file.

[0096] In this embodiment, perform slope division on the digital elevation map of the vegetation coverage area, and calculate the slope surface greening rate in different slope intervals, including:

[0097] According to the set slope interval , divide the digital elevation map of the vegetation coverage area into multiple slope intervals, that is ;

[0098] Calculate the slope surface area values corresponding to each slope interval, expressed as:

[0099]

[0100] Wherein, represents the slope interval serial number, belonging to 1~n;

[0101] After performing matrix processing on the slope surface area values and vegetation coverage area determination values corresponding to each slope interval, perform Hadamard multiplication operation to obtain the slope surface area value of the vegetation coverage area under each slope interval, expressed as:

[0102]

[0103] Based on the slope surface area values of the vegetation-covered areas in each slope interval and the slope surface area values corresponding to each slope interval, calculate the slope surface greening rate for each slope interval, expressed as:

[0104]

[0105] wherein, represents the slope surface greening rate, represents the slope surface area value of the vegetation-covered area, represents the slope surface area value, represents the position serial number in the horizontal and vertical directions of the raster file, represents the slope interval serial number.

[0106] S4. According to the digital elevation map of the vegetation-covered area, use the observation point visibility analysis method to calculate the slope green view rate and the average slope green view rate at different observation positions.

[0107] In an alternative embodiment of the present invention, step S4 uses the observation point visibility analysis method to calculate the slope green view rate and the average slope green view rate at different observation positions according to the digital elevation map of the vegetation-covered area, including:

[0108] Set up observation points in the observation area and determine the positions of the observation points according to the digital elevation map of the vegetation-covered area; specifically, in this embodiment, a potential observation area is determined. For linear areas such as roads, etc., equally spaced layout is adopted on the front slope (one observation point every 25m), and the observation points outside the slope are arranged in a geometric progression (25m, 50m, 100m). For planar areas, radiate outward in a geometric progression (25m, 50m, 100m) along the front slope. Extract the elevation of the observation points from the regional digital elevation map , and calculate the height of the observation point with an average eye height of 1.6m . The position of the observation point is denoted as , as shown in Figure 4 .

[0109] Perform visibility analysis on each observation point one by one to obtain the slope visibility results; specifically, in this embodiment, use the visibility analysis tool of Arcgis pro software to perform visibility analysis on each observation point one by one, and the visibility results of the surveyed slope are:

[0110]

[0111] wherein, iii is the observation point number, i, j is the projection coordinate of the raster unit of the slope. As shown in Figure 5 .

[0112] Calculate the slope perception area value according to the pitch angle of the line of sight of the observation point and the proportional relationship between the distance and the size; specifically, in this embodiment, according to the pitch angle of the line of sight of the observation point and the proportional relationship between the distance and the size, where the upward view result is calculated based on the vertical projection, the downward view result is calculated based on the horizontal projection, and the distance effect is obtained by dividing the projected area by the observation distance, calculate the slope perception area value, expressed as:

[0113]

[0114]

[0115]

[0116] Among them, represents the slope perception area value, represents the slope value, represents the size of the grid cell, represents the observation point iii and the observed position the distance between them, represents the pitch angle. As Figure 6 shown.

[0117] After matrix processing the slope perception area value and the slope field of view result, perform the Hadamard multiplication operation to obtain the perceived area value within the field of view, expressed as:

[0118]

[0119] Among them, the area where the result is 0 is the invisible area, and the area where the result is non-zero is the perceived area of the visible area.

[0120] After matrix processing the perceived area value within the field of view and the vegetation coverage area determination value, perform the Hadamard multiplication operation to obtain the vegetation perceived area value within the field of view, expressed as:

[0121]

[0122] Calculate the slope green view rate at different observation positions according to the perceived area value within the field of view and the vegetation perceived area value within the field of view, expressed as:

[0123]

[0124] Among them, represents the observation point iii the slope green view rate of, represents the vegetation perceived area value within the field of view, represents the perceived area value within the field of view, represents the position serial number in the horizontal and vertical directions of the grid file.

[0125] After removing the abnormal data of the green view rate at different observation positions, calculate the average value of the green view rate to obtain the average green view rate of the slope.

[0126] In this embodiment, the quartile range method is used to remove the abnormal data of the green view rate, and the average value of the green view rate after removing the abnormal values is obtained. The result is the average result of the green view rate of the surveyed slope.

[0127] The present invention can be used for the rapid evaluation of the greening effect of slope ecological engineering. The present invention can be used in the design stage, such as not planting precious plants in the non-visible range; it can be used for the detection in the construction and maintenance projects to quantitatively reveal the positions and areas with poor greening effects; it can be used for the acceptance evaluation of slope ecological engineering to quantitatively describe the quality of the greening effect and describe the benefits of the project in terms of functionality and landscape.

[0128] The present invention is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, and the combination of processes and / or blocks in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate for implementing in the process Figure 1 one process or multiple processes and / or blocks Figure 1 a device for the functions specified in one block or multiple blocks.

[0129] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured product including an instruction device, and the instruction device implements in the process Figure 1 one process or multiple processes and / or blocks Figure 1 the functions specified in one block or multiple blocks.

[0130] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0131] In the present invention, specific embodiments are used to illustrate the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. At the same time, for those of ordinary skill in the art, based on the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

[0132] Those of ordinary skill in the art will realize that the embodiments described herein are for helping the reader understand the principles of the present invention, and it should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those of ordinary skill in the art can make various other specific deformations and combinations that do not depart from the essence of the present invention according to these technical revelations disclosed in the present invention, and these deformations and combinations are still within the protection scope of the present invention.

Claims

1. A method for evaluating the greening rate of a slope ecological project, characterized in that: The following steps are involved: Obtain digital elevation maps and orthophotos of the slopes; According to the orthophoto, the slope is divided into vegetation-covered area and non-vegetation-covered area based on the visible light difference vegetation index; According to the digital elevation map of the vegetation coverage area, the slope division method is used to calculate the overall slope greening rate and the slope greening rate of different slope intervals; According to the digital elevation map of the vegetation coverage area, the observation point viewshed analysis method is used to calculate the slope green view rate and the average slope green view rate at different observation positions, including: Observation points are arranged in the observation area, and the locations of the observation points are determined based on the digital elevation map of the vegetation-covered area; Perform viewshed analysis on each observation point one by one to obtain the slope viewshed results; According to the pitch angle of the observation point and the ratio of distance and size, the slope perception area value is calculated as follows: in, represents the slope perception area value, Indicates the slope value, represents the size of the grid cell, Indicates observation point iii and the observed position The distance between Indicates the pitch viewing angle; After matrix processing of the slope perception area value and the slope viewshed result, Hadamard multiplication operation is performed to obtain the perception area value within the viewshed range; After matrix processing of the perceived area value and the vegetation coverage area determination value within the visual range, Hadamard multiplication operation is performed to obtain the vegetation perceived area value within the visual range; According to the perceived area value within the visual range and the perceived area value of vegetation within the visual range, the green viewing rate of the slope at different observation positions is calculated; After eliminating abnormal data of the green viewing rate of the slope at different observation positions, the average green viewing rate is calculated to obtain the average green viewing rate of the slope.

2. A slope ecological engineering greening rate assessment method according to claim 1, characterized in that: According to the orthophoto, the slope is divided into vegetation-covered area and non-vegetation-covered area based on the visible light difference vegetation index, including: The visible light difference vegetation index is calculated based on the orthophoto, expressed as: in, represents the visible light difference vegetation index, Represents the green band, red band, and blue band of the RGB image. Indicates the position number of the raster file in the horizontal and vertical directions; The slopes whose visible light difference vegetation index is greater than the set threshold are divided into vegetation-covered areas, and the slopes whose visible light difference vegetation index is less than or equal to the set threshold are divided into non-vegetation-covered areas.

3. The method for evaluating the greening rate of a slope ecological project according to claim 1 is characterized in that: According to the digital elevation map of the vegetation coverage area, the slope division method is used to calculate the overall slope greening rate and the slope greening rate of different slope intervals, including: Grid the digital elevation map of the vegetation-covered area and calculate the overall slope greening rate; The digital elevation map of the vegetation coverage area is divided into slopes, and the slope greening rates of different slope ranges are calculated.

4. A slope ecological engineering greening rate assessment method according to claim 3, characterized in that: Grid the digital elevation map of the vegetation-covered area and calculate the overall slope greening rate, including: Divide the digital elevation map of the vegetation-covered area into grids and calculate the slope value corresponding to each grid; According to the slope value corresponding to each grid, calculate the slope area value corresponding to each grid; The slope area value and vegetation coverage area determination value corresponding to each grid are matrixed and then Hadamard multiplication operation is performed to obtain the slope area value of the vegetation coverage area; The overall slope greening rate is calculated based on the slope area value of the vegetation coverage area and the slope area value corresponding to each grid.

5. A slope ecological engineering greening rate assessment method according to claim 4, characterized in that: The calculation method of the overall slope greening rate is: in, Represents the overall slope greening rate, Indicates the slope area value of the vegetation coverage area. Indicates the slope area value. Indicates the position number of the raster file in the horizontal and vertical directions.

6. A slope ecological engineering greening rate assessment method according to claim 3, characterized in that: The digital elevation map of the vegetation coverage area is divided into slopes, and the slope greening rate of different slope intervals is calculated, including: According to the set slope interval, the digital elevation map of the vegetation coverage area is divided into multiple slope intervals; Calculate the slope area value corresponding to each slope interval; The slope area values ​​and vegetation coverage area determination values ​​corresponding to each slope interval are matrixed and then Hadamard multiplication is performed to obtain the slope area values ​​of the vegetation coverage area under each slope interval; The slope greening rate of each slope interval is calculated based on the slope area value of the vegetation coverage area under each slope interval and the slope area value corresponding to each slope interval.

7. A slope ecological engineering greening rate assessment method according to claim 6, characterized in that: The calculation method of slope greening rate in each slope interval is: in, Indicates the slope range The slope greening rate, Indicates the slope range The slope area value of the vegetation coverage area, Indicates the slope range The slope area value, Indicates the position number of the raster file in the horizontal and vertical directions.

8. The method for evaluating the greening rate of a slope ecological project according to claim 1 is characterized in that: The calculation method of slope green view rate at different observation positions is: in, Indicates observation point iii The slope green view rate, Indicates the perceived area value of vegetation within the field of view. Represents the perceived area value within the field of view. Indicates the position number of the raster file in the horizontal and vertical directions.

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