A method, product, medium and device for evaluating the value of vegetation climate regulation

Abstract

The present invention discloses a method, product, medium and device for evaluating the vegetation climate regulation value, which relates to the field of environmental protection. First, the present invention obtains the surface net radiation and latent heat flux of vegetation and bare land in the window staggered area through the window analysis method; calculates the difference in sensible heat flux between vegetation and bare land in the window staggered area according to the surface net radiation and latent heat flux of vegetation and bare land in the window staggered area; and obtains the climate regulation value of vegetation based on the difference in sensible heat flux between vegetation and bare land in the window staggered area and in combination with the alternative cost method of air-conditioning cooling. The method of the present invention effectively avoids the problem of uncertain microclimate volume in the cooling value method, and at the same time introduces surface net radiation and latent heat flux on the basis of the transpiration amount method, improving the existing method for evaluating the vegetation climate regulation value and making the finally obtained vegetation climate regulation value more accurate.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental protection, and particularly relates to a method, product, medium and device for evaluating the climate regulation value of vegetation. Background Art

[0002] With the intensification of global warming, the climate regulation service of vegetation has received increasing attention, but its value evaluation method is not yet perfect. Existing research mostly uses the temperature reduction degree method or the transpiration method to evaluate the climate regulation value of vegetation. Among them, the temperature reduction degree method monitors the temperature reduction degree of vegetation, assumes that each square meter of vegetation affects the microclimate environment with a bottom area of 10 square meters and a height of 100 meters, converts the cooling effect of vegetation in the microclimate into the absorbed heat through the specific heat capacity of air, and then converts the heat into air-conditioning power consumption; however, there is a great uncertainty in the assumed microclimate in this method. Especially in contiguous vegetation, the microclimates interact with each other, and the estimation method of expanding the bottom area by 10 times will overestimate the climate regulation value of vegetation. The transpiration method directly converts the transpiration of vegetation into energy through the heat of vaporization and then calculates the air-conditioning power consumption. However, this method ignores the difference in the net surface radiation between forests and bare land. The net surface radiation of forests is higher than that of bare land, which can bring a certain warming effect, resulting in a large difference between the evaluated climate regulation value and the actual value. Summary of the Invention

[0003] The purpose of the present invention is to provide a method, product, medium and device for evaluating the climate regulation value of vegetation to improve the accuracy of evaluating the climate regulation value of vegetation.

[0004] To achieve the above purpose, the present invention provides the following solutions.

[0005] On the one hand, the present invention provides a method for evaluating the climate regulation value of vegetation, including:

[0006] Obtaining the net surface radiation and latent heat flux of vegetation and bare land in the window staggered area through window analysis;

[0007] Calculating the difference in sensible heat flux between vegetation and bare land in the window staggered area according to the net surface radiation and latent heat flux of vegetation and bare land in the window staggered area;

[0008] Based on the difference in sensible heat flux between vegetation and bare land in the window staggered area, combining with the alternative cost method of air-conditioning cooling to obtain the climate regulation value of vegetation.

[0009] Optionally, the obtaining the net surface radiation and latent heat flux of vegetation and bare land in the window staggered area through window analysis specifically includes:

[0010] Reading the tif file of the target area, obtaining the geographical location data of each tif file and reprojection to the same projection coordinate system;

[0011] Obtain the four boundaries of the maximum range of all tif files as the area to be divided, and divide the area to be divided into grid areas with a size of 3×2 pixels;

[0012] Use the window search method to process the grid area to obtain the window intersection area with both vegetation and bare land;

[0013] Obtain the average values of the surface net radiation and latent heat flux of vegetation and bare land in the window intersection area through window data statistics.

[0014] Optionally, the step of using the window search method to process the grid area to obtain the window intersection area with both vegetation and bare land specifically includes:

[0015] Create a window with a size of 5×3 pixels, traverse the surface net radiation and latent heat flux data of the vegetation area and the bare land area respectively, with a step size of 3 times the pixel in the x direction and 2 times the pixel in the y direction;

[0016] Extract 5×3 pixel values from the window. If there are pixel values greater than 0 in the windows of the vegetation area and the bare land area for both the surface net radiation and the latent heat flux, then determine this window as the intersection area.

[0017] Optionally, the step of calculating the difference in sensible heat flux between vegetation and bare land in the window intersection area specifically includes:

[0018] Calculate the difference in sensible heat flux between vegetation and bare land in the window intersection area through the heat balance equation of the earth's surface and using the raster computer tool of ArcGIS.

[0019] Optionally, the step of calculating the difference in sensible heat flux between vegetation and bare land in the window intersection area specifically includes:

[0020] Use the formula H vege =Rn vege -LE vege to calculate the sensible heat flux H vege in the vegetation area; where Rn vege is the surface net radiation in the vegetation area, and LE vege is the latent heat flux in the vegetation area;

[0021] Use the formula H bare =Rn bare -LE bare to calculate the sensible heat flux H bare in the bare land area; where Rn bare is the surface net radiation in the bare land area, and LE bare is the latent heat flux in the bare land area;

[0022] Use the formula ΔH = H vege -Hbare Calculate the difference in sensible heat flux ΔH between vegetation and bare land in the window interleaving area.

[0023] Optionally, based on the difference in sensible heat flux between vegetation and bare land in the window interleaving area, and combined with the alternative cost method of air-conditioning cooling, the climate regulation value of vegetation is obtained, specifically including:

[0024] Based on the difference in sensible heat flux ΔH between vegetation and bare land in the window interleaving area, use the formula Nc = ΔH ÷ RC to calculate the number of air-conditioning units Nc required for cooling per square meter; where RC is the heat absorption of one air-conditioning unit per hour for cooling.

[0025] Use the formula V = Nc × EC × P to calculate the climate regulation value V of vegetation; where Ec is the power consumption of one air-conditioning unit per hour, and P is the electricity price.

[0026] On the other hand, the present invention also provides a computer program product, including a computer program, which when executed by a processor implements the method for evaluating the climate regulation value of vegetation.

[0027] On the other hand, the present invention also provides a computer-readable storage medium, on which a computer program is stored, which when executed by a processor implements the method for evaluating the climate regulation value of vegetation.

[0028] On yet another aspect, the present invention also provides a computer device, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor executes the computer program to implement the method for evaluating the climate regulation value of vegetation.

[0029] According to the specific embodiments provided by the present invention, the following technical effects are disclosed:

[0030] The present invention compares the surface net radiation and latent heat flux of vegetation with adjacent bare land within a 5-kilometer grid range through the moving window analysis method, and obtains the difference in sensible heat flux between vegetation and bare land by the energy difference method. Sensible heat flux can directly reflect the surface temperature and has a good characterization effect on the cooling effect of vegetation. Taking the difference in sensible heat flux between vegetation and bare land as an important index for quantifying the climate regulation value, and then converting the difference in sensible heat flux into air-conditioning power consumption to calculate the climate regulation value. The method of the present invention effectively avoids the problem of uncertain microclimate volume in the cooling value method, and at the same time introduces surface net radiation and latent heat flux on the basis of the transpiration amount method, improving the existing method for evaluating the climate regulation value of vegetation, making the finally obtained climate regulation value of vegetation more accurate. Description of the Drawings

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0032] Figure 1 It is a flowchart of the vegetation climate regulation value evaluation method provided by the present invention;

[0033] Figure 2 It is a schematic diagram of the principle of the window analysis method adopted by the present invention. Specific embodiments

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0035] A vegetation climate regulation value evaluation method, product, medium and device of the present invention are provided to improve the accuracy of vegetation climate regulation value evaluation.

[0036] To make the above objects, features and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0037] Figure 1 It is a flowchart of the vegetation climate regulation value evaluation method provided by the present invention. See Figure 1 A vegetation climate regulation value evaluation method provided by the present invention includes:

[0038] Step 1: Obtain the surface net radiation and latent heat flux of vegetation and bare land in the window intersection area through the window analysis method.

[0039] The present invention adopts the moving window method. Functions based on Python native libraries and third-party libraries are used for processing to obtain the average values of the surface net radiation and latent heat flux of vegetation and bare land in the window intersection area respectively. The specific steps are as follows:

[0040] Step 1.1: Read the tif file of the target area, obtain the geographical location data of each tif file and reproject it to the same projection coordinate system.

[0041] Combined with Python's native libraries and third-party libraries, each tif file in the target area is read as a two-dimensional matrix, and the geographical location data of the tif is also read. The Python native libraries and third-party libraries used can be rasterio, os, math, pickle, glob, numpy, shapefile, pyproj, tqdm, etc.

[0042] The tif files in the target area are obtained by specialized data acquisition devices and are three-dimensional data files. The first-dimensional data is the longitude information of a certain point on the earth, the second-dimensional data is the latitude information of a certain point on the earth, and the third-dimensional data is a certain data value at this point, such as surface net radiation, latent heat flux, etc. If the tif file is opened with an image software, it shows a map file; if it is opened with data processing software, it is a data file. In the present invention, the three-dimensional data of the tif file, including its longitude and latitude, surface net radiation, and / or latent heat flux information, is read through Python software. In step 1.1, only the two-dimensional matrix, that is, the longitude and latitude information, needs to be read for the geographical location data, which is used to generate a grid in space in step 1.2. This geographical location may be in the vegetation area or the bare area in space.

[0043] For the geographical location data obtained by reading the tif files in the target area, during the data processing, it is necessary to re-project the data with inconsistent projection coordinate systems first. When calculating, the situation of inconsistent geographical ranges needs to be considered, and the windows are aligned by calculating the corresponding geographical locations. Taking the projection coordinate system of one of the data as a reference, the projection coordinate systems of other data need to be the same as it.

[0044] Step 1.2: Obtain the four boundaries of the maximum range of all tif files as the area to be divided, and divide the area to be divided into grid areas with a size of 3×2 pixels.

[0045] Traverse and read all tif files, obtain the four boundaries of all tif files, and take the four boundaries of the maximum range as the area to be divided. Within the four boundaries of this area to be divided, based on the tif pixel size, calculate the four vertices of each grid with a size of 3×2 pixels to generate a grid area.

[0046] Step 1.3: Use the window search method to process the grid area to obtain the window interleaved area with both vegetation and bare land.

[0047] Such as Figure 2As shown in the figure, a window with a size of 5×3 pixels is created, and the window data is recorded in matrix form. The rows and columns of the matrix represent the longitude and latitude information of a certain point on the earth, and the element value corresponding to a certain row and column is the surface net radiation or latent heat flux data at that longitude and latitude position. The tif data of the surface net radiation and latent heat flux in the vegetation area and the bare land area (also called the control area) are traversed using a window with a size of 5×3 pixels, and the step size is (window width - overlap width), that is, the step size in the x direction is 5 - 2 = 3 times the pixel, and the step size in the y direction is 3 - 1 = 2 times the pixel. Through python, 5×3 pixel values are read from the matrices of the surface net radiation and latent heat flux with a size of 5×3 pixels in the vegetation area and the bare land area respectively. If there are values greater than 0 in the 5×3 windows of the surface net radiation and latent heat flux in the vegetation area and the control area, then this window is determined as the staggered area.

[0048] Step 1.4: Obtain the average values of the surface net radiation and latent heat flux of vegetation and bare land in the window staggered area through window data statistics.

[0049] The vegetation area and the control area are classified spatially according to land use data. The control area is bare land, and the surface net radiation and latent heat flux in the vegetation area and the bare land area are used as target parameters. For the windows in the vegetation area and the bare land area, the average value of the target parameter = the sum of all pixel values greater than zero ÷ the number of pixel values greater than zero. For example, for the 15 values in the 5×3 moving window, only 3 pixel values are greater than zero. The sum of all pixel values greater than zero is the sum of these 3 pixel values, the number of pixel values greater than zero is 3, and the average value of the target parameter is the sum divided by 3.

[0050] According to the number of rows and columns of the two-dimensional matrix (including the geographical location information of each tif file) read from the tif files of the surface net radiation and latent heat flux in the vegetation area and the bare land area in Step 1.1, a new empty matrix with a size of 3×2 pixels and all values being 0 is created to store the average value calculation results of the window staggered area in Step 1.4. Denote the average value of the surface net radiation in the vegetation area in the window staggered area as Rn vege , denote the average value of the latent heat flux in the vegetation area in the window staggered area as LE vege ; denote the average value of the surface net radiation in the bare land area in the window staggered area as R bare , denote the average value of the latent heat flux in the bare land area in the window staggered area as LE bare .

[0051] Step 2: Calculate the difference in sensible heat flux between vegetation and bare land in the window staggered area according to the surface net radiation and latent heat flux of vegetation and bare land in the window staggered area.

[0052] Based on the heat balance equation of the earth's surface and using the raster computer tools of ArcGIS, the present invention calculates the difference in sensible heat fluxes between vegetation and bare land within the window intersection area, that is, calculates the differences in net radiation and latent heat fluxes of the land surface in the vegetation area and the bare land area respectively.

[0053] Net radiation and latent heat flux of the land surface are two major factors affecting land surface temperature and vegetation climate regulation. Sensible heat flux (also known as sensible heat flux, H) is the heat exchange between the atmosphere and the land surface caused by temperature changes. The change in sensible heat flux is manifested as an increase or decrease in land surface temperature. According to the heat balance equation of the earth's surface, the difference in sensible heat fluxes between vegetation and bare land is calculated using formulas (1) to (3).

[0054] H vege =Rn vege -LE vege (1)

[0055] H bare =Rn bare -LE bare (2)

[0056] ΔH = H vege -H bare (3)

[0057] Where H vege is the sensible heat flux of the vegetation area, Rn vege is the net radiation of the land surface in the vegetation area, LE vege is the latent heat flux of the vegetation area; H bare is the sensible heat flux of the bare land area, Rn bare is the net radiation of the land surface in the bare land area, LE bare is the latent heat flux of the bare land area; Rn vege 、LE vege 、Rn bare 、LE bare all take the average value within the window intersection area; ΔH is the difference in sensible heat fluxes between vegetation and bare land within the window intersection area, and the unit is MJ / m 2 / day.

[0058] Step 3: Based on the difference in sensible heat fluxes between vegetation and bare land within the window intersection area, the climate regulation value of vegetation is obtained by combining the alternative cost method of air-conditioning cooling.

[0059] Sensible heat flux can directly reflect land surface temperature. The energy difference in sensible heat fluxes between vegetation and bare land in the intersection area can characterize the climate regulation effect of vegetation, that is, the temperature reduction degree. Using the alternative cost method, an air conditioner with a certain cooling capacity is used to replace the heat absorption of vegetation, and the saved air conditioner electricity cost is used to replace the climate regulation value of vegetation. Formulas (4) and (5) are used to convert the energy difference in sensible heat fluxes between vegetation and bare land in the intersection area into air conditioner power consumption, and the climate regulation value of vegetation is calculated.

[0060] Nc = ΔH ÷ RC (4)

[0061] V = Nc × EC × P (5)

[0062] Wherein, V is the climate regulation value of vegetation (yuan / m 2 / day); Nc is the number of one - horsepower air conditioners required for cooling per square meter (units); Ec is the power consumption of one - horsepower air conditioner per hour (kWh); P is the electricity price (CNY / kWh); ΔH is the difference in sensible heat flux between vegetation and bare land (MJ / m 2 / day); RC is the heat absorption for cooling of one - horsepower air conditioner per hour (MJ / m 2 / day). In some embodiments, RC = 2.5KW × 3600 / 1000, EC = 0.735kWh, P = 0.49CNY / kWh.

[0063] The method for evaluating the climate regulation value of vegetation provided by the present invention first obtains the surface net radiation and latent heat flux of vegetation and bare land that simultaneously appear within a 5 - km grid range through the window analysis method, secondly calculates the difference in sensible heat flux between vegetation and bare land in the staggered area, then combines with the alternative cost method of air - conditioner cooling, and finally obtains the evaluation value of the climate regulation value of vegetation, thereby providing a scientific basis for the evaluation of the service value of the vegetation ecosystem and achieving the technical effect of improving the accuracy of vegetation climate regulation. The evaluation of the service value of the vegetation ecosystem includes multiple service functions such as water conservation, soil conservation, wind prevention and sand fixation, and climate regulation. The climate regulation value is a part of the service value. Different geographical locations have large differences in climate regulation. V > 0 indicates that the vegetation in the target area has climate regulation function, and the larger V is, the higher the climate regulation value is.

[0064] In some embodiments, the present invention also provides a computer program product, including a computer program, which when executed by a processor implements the method for evaluating the climate regulation value of vegetation.

[0065] In some embodiments, the present invention also provides a computer - readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the method for evaluating the climate regulation value of vegetation.

[0066] In some embodiments, the present invention further provides a computer device, which includes a processor, a memory, an input / output interface (Input / Output, abbreviated as I / O), and a communication interface. Among them, the processor, the memory, and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store transactions to be processed. The input / output interface of the computer device is used to exchange information between the processor and external devices. The communication interface of the computer device is used to communicate with external terminals through a network connection. When the computer program is executed by the processor, it can implement the vegetation climate regulation value evaluation method.

[0067] Specific examples are used in this article to elaborate on the principles and implementation manners of the present invention. The descriptions of the above embodiments are 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, according to 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.

Claims

1. A vegetation climate regulation value assessment method, characterized in that: include: The net surface radiation and latent heat flux of vegetation and bare land in the window intersection area are obtained by window analysis method. The net surface radiation and latent heat flux of vegetation and bare land in the window intersection area are obtained by the window analysis method, specifically including: Read the tif file of the target area, obtain the geographic location data of each tif file and reproject it to the same projection coordinate system; The three-dimensional data of the tif file is read through Python software, including longitude and latitude, surface net radiation and / or latent heat flux information; reading geographic location data only requires reading a two-dimensional matrix, i.e. longitude and latitude information, which is used to generate a grid in space; Get the four boundaries of the largest range of all tif files as the area to be divided, and divide the area to be divided into grid areas of 3×2 pixels; The grid area is processed using the window search method to obtain the window interlaced area with both vegetation and bare land; Create a window of 5×3 pixel size, and record the window data in the form of a matrix. The rows and columns of the matrix represent the longitude and latitude information of a point on the earth, and the corresponding element value at a row and a column is the surface net radiation or latent heat flux data at the longitude and latitude position; use the window of 5×3 pixel size to traverse the tif data of the surface net radiation and latent heat flux of the vegetation area and the bare area, respectively, with a step length of (window width-overlap width), that is, the step length in the x direction is 5-2=3 times the pixel, and the step length in the y direction is 3-1=2 times the pixel; read 5×3 pixel values ​​from the 5×3 pixel matrix of the surface net radiation and latent heat flux of the vegetation area and the bare area respectively through python. If the surface net radiation and latent heat flux have values ​​greater than 0 in the 5×3 window of the vegetation area and the control area, then the window is determined to be an interlaced area; The average values ​​of net surface radiation and latent heat flux of vegetation and bare land in the window intersection area are obtained through window data statistics; The net surface radiation and latent heat flux of the vegetation area and the bare area are taken as the target parameters; for the windows of the vegetation area and the bare area, the average value of the target parameter = the sum of all pixel values ​​greater than zero ÷ the number of pixel values ​​greater than zero; According to the number of rows and columns of the two-dimensional matrix read from the tif file of the net surface radiation and latent heat flux of the vegetation area and the bare area, a new empty matrix of 3×2 pixel size with all values ​​0 is created to store the average value calculation results of the window interlaced area; the average value of the net surface radiation of the vegetation area in the window interlaced area is recorded as Rn vege , the average value of latent heat flux in the vegetation area within the window intersection area is recorded as LE vege ; The average value of the net surface radiation in the bare area within the window intersection area is recorded as R bare , the average latent heat flux of the bare area in the window staggered area is recorded as LE bare ; The sensible heat flux difference between vegetation and bare land in the window interlaced area is calculated based on the surface net radiation and latent heat flux of vegetation and bare land in the window interlaced area; The calculation of the sensible heat flux difference between vegetation and bare land in the window interlaced area according to the surface net radiation and latent heat flux of vegetation and bare land in the window interlaced area specifically includes: The difference in sensible heat flux between vegetation and bare land in the window intersection area was calculated by using the earth surface heat balance equation and ArcGIS raster computer tools; The sensible heat flux difference between vegetation and bare land in the interlaced area of ​​the calculation window specifically includes: Using formula H vege =Rn vege -LE vege Calculate the sensible heat flux H in the vegetation area vege ; Rn vege is the net radiation of the vegetation area, LE vege is the latent heat flux in the vegetation area; Using formula H bare =Rn bare -LE bare Calculate the sensible heat flux H in the bare area bare ; Rn bare is the net radiation of the bare area surface, LE bare is the latent heat flux in the bare area; Using the formula ΔH=H vege -H bare Calculate the sensible heat flux difference ΔH between vegetation and bare land in the window interlaced area; Based on the difference in sensible heat flux between vegetation and bare land in the window staggered area, combined with the substitution cost method of air conditioning cooling, the climate regulation value of vegetation is obtained; The climate regulation value of vegetation is obtained by combining the sensible heat flux difference between vegetation and bare land in the window interlaced area with the substitution cost method of air conditioning cooling, which specifically includes: Based on the sensible heat flux difference ΔH between vegetation and bare land in the window staggered area, the formula Nc=ΔH÷RC is used to calculate the number of air conditioners Nc required for cooling per square meter; where RC is the amount of heat absorbed by one air conditioner per hour; The climate regulation value V of vegetation is calculated using the formula V=Nc×EC×P; where Ec is the power consumption of an air conditioner per hour; and P is the electricity price.

2. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the vegetation climate regulation value assessment method described in claim 1 is implemented.

3. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the vegetation climate regulation value assessment method described in claim 1 is implemented.

4. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the vegetation climate regulation value assessment method described in claim 1.

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