Method and device for evaluating the suitability of mangrove plant growth elevation based on species level

Abstract

The present invention discloses a method and device for evaluating the suitability of mangrove plant growth elevation based on species level, the method comprising: obtaining a 2M spatial resolution plant community distribution grid map; and constructing a 2M spatial resolution optimal flooding and critical flooding time grid map based on the grid map; extracting 1M spatial resolution DEM data; based on hyperspectral remote sensing images and data from nearby tide gauge stations, calculating the tidal height and flow velocity at key time nodes of mangrove wetlands, obtaining the annual average flooding time at different elevations of mangrove wetlands, and converting it into a 2M spatial resolution annual average flooding duration grid map; based on the 2M spatial resolution, analyzing the annual average flooding time of the same grid unit and the optimal flooding and critical flooding time of the mangrove plant community to determine the suitability of the growth elevation. The present invention can evaluate the ecological effects of existing mangrove plants, and can also adjust the plant community configuration and transform the elevation hydrological conditions accordingly, so as to provide guidance for subsequent mangrove restoration activities.

Description

Technical Field

[0001] The invention relates to the technical field of mangrove plants, and in particular to a method and device for evaluating the growth altitude suitability of mangrove plants based on species level. Background Art

[0002] Mangroves refer to wetland woody plant communities composed of evergreen shrubs or trees, mainly composed of plants of the Rhizophoraceae family, distributed in tropical and subtropical coastal intertidal zones and estuaries. They can break waves and protect embankments, resist marine natural disasters, protect biodiversity, and improve the coastal ecological environment. They are internationally recognized blue carbon pools and play an extremely important role in addressing global climate change and achieving the goal of "carbon neutrality".

[0003] After nearly 20 years of rapid afforestation and ecological restoration efforts, the area of ​​mangrove plants in China has increased significantly, but the structure and function of the ecosystem are still degrading. How to improve the quality of mangrove wetland ecosystems and enhance their ecological functions, that is, how to maximize the ecological benefits of limited mangrove wetland areas, has become a core issue currently faced by scientific research and management personnel.

[0004] Numerous studies have shown that flooding time has a significant impact on mangrove plant morphology, photosynthesis, respiration, antioxidant system, etc. Too long or too short a flooding time will affect the growth of mangrove plants, reduce the effect of wetland restoration and hinder the improvement of ecological functions. Tidal flat afforestation is currently the main way to restore mangroves in China. According to statistics, about 70% of mangroves in my country are newly planted in the later period. Elevation suitability evaluation of afforestation land is conducive to objectively understanding the quality of mangrove ecosystems, providing a reference for the current evaluation of mangrove wetland restoration results, and can adjust plant community configuration and transform elevation hydrological conditions accordingly, providing guidance for subsequent mangrove restoration activities.

[0005] At present, the most suitable growth elevation of mangrove plants is mainly determined through field positioning experiments. The experimental period is long, the cost is high, the results are rough, and they are mostly displayed in large areas. There is a lack of detailed evaluation methods for the elevation suitability of plant communities at the species level. In addition, due to the different hydrological conditions in each study area, the application scope of the experimental results is limited. Although there are methods to determine the suitable growth elevation for unforested land to guide afforestation practices, there is a lack of methods to evaluate the elevation suitability of plant communities in afforestation areas. At the same time, there is a lack of methods and devices based on remote sensing big data that can be operated in a process-oriented and low-cost manner to evaluate the elevation suitability of mangrove plants in afforestation areas. Summary of the invention

[0006] In order to overcome the deficiencies of the prior art, an embodiment of the present invention aims to provide a method and device for evaluating the suitability of mangrove plant growth altitude based on species level, which can evaluate the suitability of mangrove plant growth altitude.

[0007] To solve the above problems, the first aspect of the embodiment of the present invention discloses a method for evaluating the growth altitude suitability of mangrove plants based on the species level, which comprises the following steps:

[0008] Based on hyperspectral remote sensing images and field tree species survey verification sampling points, the plant community structure distribution map of the study area was obtained and converted into a plant community raster map with a spatial resolution of 2M;

[0009] Based on the plant community type in each grid, the optimal flooding time and critical flooding time of different types of plants were obtained, and the optimal flooding time grid map and critical flooding time grid map with a spatial resolution of 2M were constructed.

[0010] Based on high-precision LiDAR point cloud data, DEM data with a spatial resolution of 1M was extracted from the study area. Based on hyperspectral remote sensing images and tide data from nearby tide gauges, the tidal height and flow velocity at key time nodes of the mangrove wetlands in the study area were calculated according to the tidal type, season and daily variation of the study area. The daily average flooding time of the mangrove wetlands at different elevations in four seasons was calculated, and the annual daily average flooding time was further obtained, which was converted into an annual average flooding time raster map with a spatial resolution of 2M in combination with DEM data.

[0011] Based on a unified 2M spatial resolution, the annual average flooding time, optimal flooding time and critical flooding time of the same grid unit were compared and analyzed to determine the elevation suitability of mangrove plant growth in the study area.

[0012] As a preferred implementation, in the first aspect of the embodiment of the present invention, according to the tidal type, season and daily variation law of the study area, the tidal height and flow rate at the key time nodes of the mangrove wetland in the study area are calculated; the daily average flooding time of the mangrove wetland at different elevations in four seasons is calculated, and the annual daily average flooding time is further obtained, and the DEM data is combined to convert it into an annual average flooding time grid map with a spatial resolution of 2M, including:

[0013] Determine the daily flooding time of the mangrove wetland at different elevations according to the tidal type, tidal height, flow velocity and tidal height time, and construct a daily average flooding duration raster map with a spatial resolution of 2M;

[0014] Automatically calculate the average flooding time in each season based on the daily flooding time;

[0015] The annual average flooding duration raster map is calculated based on the average flooding duration of each season.

[0016] As a preferred implementation, in the first aspect of the embodiment of the present invention, when the tidal type is a semi-diurnal tide, then:

[0017] Tidal velocity v = (H high-H low ) / (T1-T2);

[0018] Height D in [H high -n*v,H high -(n-1)*v], the corresponding daily flooding time is T=n*2*2;

[0019] When the height D <H low , the corresponding daily flooding time T = 24h;

[0020] When the elevation D>H high , the corresponding daily flooding time T = 0h;

[0021] Among them, H high Indicates the height of the tide at the highest point, H low represents the tide height at the lowest tide moment, T1 and T2 represent the time of the highest tide and the lowest tide respectively within 1 / 4 tidal cycle, n represents the duration of low tide (h); v represents the average tidal velocity of the day (cm / h), D represents the surface elevation of any point (cm), and T represents the flooding time of the day at any point in the corresponding elevation range.

[0022] As a preferred implementation, in the first aspect of the embodiment of the present invention, when the tidal type is a diurnal tide, then:

[0023] v=(H high -H low ) / (T1-T2);

[0024] Height D in [H high -n*v,H high -(n-1)*v], the corresponding daily flooding time is T=n*2;

[0025] When the height D <H low , the corresponding daily flooding time T = 24h;

[0026] When the elevation D>H high , the corresponding daily flooding time T = 0h;

[0027] Among them, H high Indicates the height of the tide at the highest point, H low represents the tide height at the lowest tide moment, T1 and T2 represent the time of the highest tide and the lowest tide respectively within 1 / 2 tidal cycle within 24 hours, n represents the duration of low tide (h); v represents the average tidal velocity of the day (cm / h), D represents the surface elevation of any point (cm), and T represents the flooding time of the day at any point in the corresponding elevation range.

[0028] As a preferred implementation, in the first aspect of the embodiment of the present invention, based on a unified 2M spatial resolution, the annual average flooding time, the optimal flooding time, and the critical flooding time of the same grid unit are compared and analyzed to determine the height suitability of mangrove plant growth in the study area, including:

[0029] According to the optimal flooding time and critical flooding time of plant community types, the upper limit and lower limit of the optimal flooding time and the critical flooding time in each grid unit of the study area were determined;

[0030] Determine the average flooding duration in each grid cell of the study area based on the annual average flooding duration grid map with a spatial resolution of 2M;

[0031] The suitability of the growth elevation of the mangrove plant community in the grid unit is determined based on the upper limit of the optimal flooding time, the lower limit of the optimal flooding time, the critical flooding time and the annual average flooding duration of the plant community in the grid unit.

[0032] As a preferred implementation, in the first aspect of the embodiment of the present invention, the suitability of the growth elevation of the mangrove plant community in the grid unit is determined according to the upper limit of the optimal flooding time, the lower limit of the optimal flooding time, the critical flooding time and the annual average flooding time of the plant community in the grid unit, including:

[0033] When the average flooding duration in the target unit grid is less than the lower limit of the optimal flooding time of the plant community in the unit grid or the average flooding duration in the target unit grid is greater than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is not suitable for the growth of the mangrove plant;

[0034] When the average flooding duration of the target unit grid is greater than the upper limit of the optimal flooding time of the plant community of the unit grid and the average flooding duration of the target unit grid is less than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is more suitable for the growth of the mangrove plant;

[0035] When the average flooding duration of the target unit grid is greater than or equal to the lower limit of the optimal flooding time of the plant community and the average flooding duration of the target grid is less than or equal to the upper limit of the optimal flooding time of the plant community, then from the perspective of elevation, the target unit grid is very suitable for the growth of the mangrove plant.

[0036] A second aspect of an embodiment of the present invention discloses a device for evaluating the suitability of mangrove plant growth elevation based on species level, comprising:

[0037] The acquisition unit is used to verify the sample points based on hyperspectral remote sensing images and field tree species surveys, obtain the plant community structure distribution map of the study area, and convert it into a plant community raster map with a spatial resolution of 2M;

[0038] A construction unit is used to obtain the optimal flooding time and critical flooding time of different types of plants based on the plant community type in each grid, and to construct an optimal flooding time grid map and a critical flooding time grid map with a spatial resolution of 2M;

[0039] The calculation unit is used to extract DEM data with a spatial resolution of 1M in the study area based on high-precision lidar point cloud data; based on hyperspectral remote sensing images and tide data from nearby tide gauges, the tidal height and flow velocity at key time nodes of the mangrove wetlands in the study area are calculated according to the tidal type, season and daily variation of the study area; the daily average flooding time of the mangrove wetlands at different elevations in four seasons is calculated, and the annual daily average flooding time is further obtained, which is converted into an annual average flooding time raster map with a spatial resolution of 2M in combination with the DEM data;

[0040] The evaluation unit is used to compare and analyze the annual average flooding time, optimal flooding time and critical flooding time of the same grid unit based on a unified 2M spatial resolution, so as to determine the elevation suitability of mangrove plant growth in the study area.

[0041] As a preferred implementation, in the second aspect of the embodiment of the present invention, the computing unit includes:

[0042] The first determination subunit is used to determine the daily flooding time of the mangrove wetland at different elevations according to the tidal type, tidal height, flow velocity and tidal height time, and to construct a daily average flooding time grid map with a spatial resolution of 2M;

[0043] A calculation subunit, used for automatically calculating the average flooding time of each season according to the daily flooding time;

[0044] A subunit is constructed for calculating a grid map of annual average flooding duration based on the average flooding duration of each season.

[0045] As a preferred implementation, in the second aspect of the embodiment of the present invention, the evaluation unit includes:

[0046] The second determination subunit is used to determine the upper limit of the optimal flooding time, the lower limit of the optimal flooding time, and the critical flooding time in the grid unit of the study area according to the optimal flooding time and the critical flooding time of the plant community type respectively;

[0047] The third sub-unit is determined, and the average flooding duration in each grid unit of the study area is determined according to the annual average flooding duration grid map with a spatial resolution of 2M;

[0048] The fourth determination subunit is used to determine the suitability of the growth elevation of the mangrove plant community in the grid unit according to the upper limit of the optimal flooding time, the lower limit of the optimal flooding time, the critical flooding time and the annual average flooding time of the plant community in the grid unit.

[0049] As a preferred implementation, in the second aspect of the embodiment of the present invention, the fourth determining subunit includes:

[0050] When the average flooding duration in the target unit grid is less than the lower limit of the optimal flooding time of the plant community in the unit grid or the average flooding duration in the target unit grid is greater than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is not suitable for the growth of the mangrove plant;

[0051] When the average flooding duration of the target unit grid is greater than the upper limit of the optimal flooding time of the plant community of the unit grid and the average flooding duration of the target unit grid is less than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is more suitable for the growth of the mangrove plant;

[0052] When the average flooding duration of the target unit grid is greater than or equal to the lower limit of the optimal flooding time of the plant community and the average flooding duration of the target grid is less than or equal to the upper limit of the optimal flooding time of the plant community, then from the perspective of elevation, the target unit grid is very suitable for the growth of the mangrove plant.

[0053] A third aspect of an embodiment of the present invention discloses an electronic device, comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor. When the processor executes the computer program, the steps of the method for evaluating the growth altitude suitability of mangrove plants based on the species level disclosed in the first aspect of the embodiment of the present invention are implemented.

[0054] A fourth aspect of an embodiment of the present invention discloses a computer-readable storage medium storing a computer program, wherein the computer program enables a computer to execute the steps of the method for evaluating the growth elevation suitability of mangrove plants based on five levels and species level disclosed in the first aspect of the embodiment of the present invention.

[0055] The fifth aspect of the embodiment of the present invention discloses a computer program product. When the computer program product is run on a computer, the computer is enabled to execute the steps of the method for evaluating the height suitability of mangrove plant growth based on the species level disclosed in the first aspect of the embodiment of the present invention.

[0056] A sixth aspect of an embodiment of the present invention discloses an application publishing platform, which is used to publish a computer program product. When the computer program product runs on a computer, the computer executes the steps of the method for evaluating the height suitability of mangrove plant growth based on the species level disclosed in the first aspect of the embodiment of the present invention.

[0057] Compared with the prior art, the invention has the following beneficial effects:

[0058] 1) The evaluation method of the present invention is a refined evaluation method based on the species level, which can realize the refined quantitative evaluation of the elevation suitability of different mangrove plant types on a small scale, which is conducive to objectively understanding the quality status of the mangrove ecosystem, providing a reference for the current evaluation of the restoration effectiveness of mangrove wetlands, and can adjust the plant community configuration and transform the elevation hydrological conditions accordingly, providing guidance for subsequent mangrove restoration activities.

[0059] 2) Compared with traditional field experiments to evaluate the elevation suitability of mangrove growth, it saves time and cost, and the operation platform is built based on remote sensing big data, which is simple, convenient and more universal.

[0060] 3) The tidal type, tidal day, and seasonal variation patterns are comprehensively considered, making the evaluation of the elevation suitability of different mangrove plant communities more comprehensive and authoritative. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 It is a flow chart of a method for evaluating the suitability of mangrove plant growth elevation based on species level disclosed in an embodiment of the present invention;

[0062] Figure 2 is a schematic diagram of the flooding time of the semi-diurnal tide disclosed in an embodiment of the present invention;

[0063] Figure 3 is a schematic diagram of flooding time of a full-day tide disclosed in an embodiment of the present invention;

[0064] Figure 4 is a schematic diagram of the structure of a device for evaluating the suitability of mangrove plant growth elevation based on species level disclosed in an embodiment of the present invention;

[0065] Figure 5 It is a schematic diagram of the structure of an electronic device disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0066] This specific implementation manner is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

[0067] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0068] The term "comprise" and any variations thereof in the specification and claims of the present application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0069] In the embodiments of the present invention, words such as "exemplarily" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplarily" or "for example" in the embodiments of the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplarily" or "for example" is intended to present related concepts in a specific way.

[0070] The following is a detailed description with reference to the accompanying drawings.

[0071] Embodiment 1

[0072] See also Figure 1 , Figure 1 FIG. 1 is a flow chart of a method for evaluating the suitability of mangrove plant growth elevation based on species level disclosed in an embodiment of the present invention. Figure 1 As shown, the species-based mangrove plant growth altitude suitability evaluation method includes the following steps:

[0073] S110. Based on hyperspectral remote sensing images and field survey verification samples, the plant community structure distribution map of the study area was obtained and converted into a 2M spatial resolution plant community raster map.

[0074] The resolution of the hyperspectral remote sensing image can be 0.5M, for example, the worldview image can be used. Obtain the plant community distribution map of the study area and resample it into a 2M raster map. This can be done using existing technologies, for example, it can be achieved through the paper "Mangrove Species Distribution by Coupling WorldView-2 and Zhuhai No. 1 Images", Gao Changjun et al., Journal of Remote Sensing, 2022, 26(6): 1155-1168.

[0075] S120, based on the plant community type in each grid, obtain the optimal flooding time and critical flooding time of different types of plants, and construct an optimal flooding time grid map and a critical flooding time grid map with a spatial resolution of 2M.

[0076] The optimal flooding time and critical flooding time for different types of plants can be obtained by consulting literature and / or conducting experiments. Table 1 shows the optimal flooding time and critical flooding time for some mangrove plants.

[0077] Table 1 Optimal flooding time and critical flooding time for some mangrove plants

[0078] Plant Type Optimal flooding time (range) Critical flooding time Acanthus 0-3h / day 18h / d Kandelia candel 4-8h / day 12h / d Sonneratia apetala 0-7h / d 18h / d Red sea olive 4-12h / day 16h / d Avicennia marina 8-12h / d 16h / d Tung tree 8-12h / d 16h / d Bruguiera gymnorrhiza 0-8h / d 12h / d silique 0-8h / d 16h / d Helian 4-8h / day 12h / d

[0079] S130. Based on high-precision LiDAR point cloud data, DEM data with a spatial resolution of 1M was extracted from the study area. Based on hyperspectral remote sensing images and tide data from nearby tide gauges, the tidal heights and flow rates at key time nodes of the mangrove wetlands in the study area were calculated according to the tidal types, seasons, and daily variations in the study area. The average daily flooding time of the mangrove wetlands at different elevations in four seasons was calculated, and the annual average daily flooding time was further obtained, which was converted into an annual average flooding time raster map with a spatial resolution of 2M based on the DEM data.

[0080] Based on hyperspectral remote sensing images and tide data from nearby tide gauges, the calculation of tidal heights and flow rates at key time points in the mangrove wetlands in the study area can be completed using existing technologies, according to the tidal types, seasons, and daily variations in the study area. For example, this can be achieved using the paper “Remote sensing monitoring and changes of China’s intertidal zones based on tidal correction”, Han Qianqian et al., Science Bulletin, 2019, 64(04): 456-473; or the paper “Remote sensing monitoring and change analysis of the coastal intertidal zones of Yancheng based on tidal correction”, Wang Jingwen et al., Acta Oceanologica Sinica, 2017, 39(05): 149-160.

[0081] The tidal height data involved here mainly include the tidal height at the highest tide moment in the tidal cycle (m), the tidal height at the lowest tide moment (m), and the time of the highest tide and the lowest tide (h).

[0082] Specific parameters of high-precision LiDAR point cloud data, as an example, can be point cloud density ≥ 80 points / m 2 The horizontal mean error of point cloud data is <0.10m, the elevation mean error is <0.35m; the plane error of orthophoto is <0.10m and the spatial resolution is <0.10m.

[0083] Extract DEM (Digital Elevation Model) data. As an example, we can use the elevation point data of the study area (such as an Excel table containing latitude, longitude and elevation data) that can be downloaded for free from the Tuxin Earth software, combined with high-precision lidar point cloud data, and then use the 3D analysis tool of Arcmap software to generate DEM images to obtain digital elevation images of the study area, and divide the elevation into vector graphs with a resolution of 1 cm.

[0084] The flooding time index here is the daily flooding time, which can determine the daily flooding time of the mangrove wetland according to the tidal flow rate, type, tidal height, and tidal height time.

[0085] For example, when the tide type is semi-diurnal tide, then:

[0086] v=(H high -H low ) / (T1-T2);

[0087] Please refer to Figure 2 As shown, when n = 0, D > H high , the corresponding daily flooding time is T = 0h;

[0088] When the elevation D is [H high -n*v,H high -(n-1)*v], the corresponding daily flooding time is T=n*2*2;

[0089] For example:

[0090] When n = 1, H high -1*v<D<H high , at this time the elevation D is [H high -1*v,H high ] The corresponding daily flooding time within the range is T=1*2*2=4;

[0091] When n = 2, H high -2*v<D<H high -1*v, height D in [H high -2*v,H high -1*v], the corresponding daily flooding time is T=2*2*2=8;

[0092] When n = 3, H high -3*v<D<H high -2*v, height D in [H high -3*v,H high -2*v], the corresponding daily flooding time is T=3*2*2=12;

[0093] When n = 4, H high -4*v<D<H high -3*v, elevation D in [H high -4*v,H high -3*v] The corresponding daily flooding time within this range is T=4*2*2=16;

[0094] …

[0095] When the height D <H low , the corresponding daily flooding time T = 24h.

[0096] When the tidal type is diurnal, then:

[0097] v=(H high -H low ) / (T1-T2);

[0098] Please refer to Figure 3 As shown, when n = 0, D > H high , the corresponding daily flooding time is T = 0h;

[0099] When the elevation D is [H high -n*v,H high -(n-1)*v], the corresponding daily flooding time is T=n*2;

[0100] For example:

[0101] When n = 1, H high -1*v<D<H high , at this time the elevation D is [H high -1*v,H high ] The corresponding daily flooding time within the range is T=1*2=2;

[0102] When n = 2, H high -2*v<D<H high -1*v, height D in [H high -2*v,H high -1*v], the corresponding daily flooding time is T=2*2=4;

[0103] When n = 3, H high -3*v<D<H high -2*v, height D in [H high -3*v,H high -2*v], the corresponding daily flooding time is T=3*2=6;

[0104] When n = 4, H high -4*v<D<H high -3*v, elevation D in [Hhigh -4*v,H high -3*v] The corresponding daily flooding time within this range is T=4*2=8;

[0105] …

[0106] When the height D <H low , the corresponding daily flooding time T = 24h;

[0107] Among them, H high Indicates the height of the tide at the highest point, H low represents the tide height at the lowest tide moment, T1 and T2 represent the time of the highest tide and the lowest tide respectively within 1 / 2 tidal cycle, n represents the duration of low tide (h); v represents the average tidal velocity of the day (cm / h), D represents the surface elevation of any point (cm), and T represents the flooding time of any point in the corresponding elevation range on the day.

[0108] The actual average flooding time of each season can be calculated according to the daily flooding time, and then a grid map of the average flooding duration of mangrove wetlands in four seasons (ie, the actual average flooding time of each season) is constructed based on the average flooding time of each season.

[0109] Based on the ArcGIS secondary development platform, process calculation can be realized. The main implementation ideas are as follows:

[0110] 1. Put the DEM raster images of different flooding times every day in a quarter into folder a;

[0111] 2. Traverse folder a and obtain the number of DEM data files b;

[0112] 3. When b is greater than or equal to 2, traverse all DEM data, accumulate them, and get sum_DEM. After the loop ends, use sum_dem / b to get the quarterly average result data and save the result to the specified folder; when b<2, the program cannot be executed, and it is prompted that at least 2 DEM data are required to calculate the average value.

[0113] The code is as follows:

[0114] import arcpy

[0115] import numpy arcpy.CheckOutExtension('Spatial')

[0116] from arcpy.sa import *

[0117] from arcpy import env env.workspace="E: / computer / code / rastertest / data1"

[0118] output_raster="E: / computer / code / rastertest / result"

[0119] rasterlist=arcpy.ListRasters()

[0120] files_nums = len(rasterlist)

[0121] print(files_nums)

[0122] if files_nums>2:

[0123] temp_raster=arcpy.Raster(rasterlist[0])

[0124] for i in range(1,files_nums):

[0125] raster_i=arcpy.Raster(rasterlist[i])

[0126] temp_raster=temp_raster+raster_i

[0127] print i

[0128] outraster=temp_raster / files_nums

[0129] outraster.save(output_raster)

[0130] else:

[0131] print("raster number is less then 2! Please put more then 2raster in the data path!").

[0132] S140. Based on a unified 2M spatial resolution, the annual average flooding time, optimal flooding time and critical flooding time of the same grid unit were compared and analyzed to determine the elevation suitability of mangrove plant growth in the study area.

[0133] The suitability of mangrove plant growth elevation in the study area here refers to the elevation of mangrove plant growth in the study area, that is, which grid units are suitable for the growth of mangrove plants in the grid unit in the average flooding time throughout the year (which can be very suitable and relatively suitable respectively), and which grid units are not suitable for the growth of mangrove plants in the grid unit in the average flooding time throughout the year. Specifically, first, the upper limit and lower limit of the optimal flooding time in each grid unit in the study area can be determined according to the optimal flooding time grid map with a spatial resolution of 2M; then, the critical flooding time in each grid unit in the study area can be determined according to the critical flooding time grid map with a spatial resolution of 2M; then, the average flooding duration in each grid unit in the study area can be determined according to the annual average flooding duration grid map with a spatial resolution of 2M; finally, the suitability of the growth elevation of the mangrove plant community in the grid unit is determined according to the upper limit of the optimal flooding time, the lower limit of the optimal flooding time, the critical flooding time and the average flooding duration of the plant community in the grid unit.

[0134] in:

[0135] When the average flooding duration in the target unit grid is less than the lower limit of the optimal flooding time of the plant community in the unit grid or the average flooding duration in the target unit grid is greater than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is not suitable for the growth of the mangrove plant;

[0136] When the average flooding duration of the target unit grid is greater than the upper limit of the optimal flooding time of the plant community of the unit grid and the average flooding duration of the target unit grid is less than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is more suitable for the growth of the mangrove plant;

[0137] When the average flooding duration of the target unit grid is greater than or equal to the lower limit of the optimal flooding time of the plant community and the average flooding duration of the target grid is less than or equal to the upper limit of the optimal flooding time of the plant community, then from the perspective of elevation, the target unit grid is very suitable for the growth of the mangrove plant.

[0138] For example, taking simple grid data as an example, the upper limit of the optimal flooding time, the lower limit of the optimal flooding time, the critical flooding time and the average flooding time in each grid unit are shown in Table 2-5 respectively:

[0139] Table 2 Grid map of plant community distribution

[0140] Kandelia candel Avicennia marina silique Bruguiera gymnorrhiza Tung tree Acanthus Sonneratia apetala Helian Red sea olive

[0141] Table 3 Grid map of the upper limit of the optimal flooding time

[0142] 8 12 8 8 12 3 7 8 12

[0143] Table 4 Grid map of the lower limit of the optimal flooding time

[0144] 4 8 0 0 8 0 0 4 4

[0145] Table 5 Critical flooding time grid map

[0146] 12 16 16 12 16 18 18 12 16

[0147] Table 6 Grid map of annual average flooding duration

[0148] 6 16 18 7 4 12 8 12 20

[0149] In the study area, the plant in the first grid unit is Kandelia ovata, and the average annual flooding duration is 6 hours. Since it is greater than or equal to the lower limit of the optimal flooding time and less than the upper limit of the optimal flooding time, it can be determined that the flooding time of the first grid unit in this season is very suitable for the growth of this mangrove plant.

[0150] Embodiment 2

[0151] Please refer to Figure 4 As shown, a device for evaluating the suitability of mangrove plant growth elevation based on species level comprises:

[0152] The acquisition unit 210 is used to obtain the plant community structure distribution map of the study area based on the hyperspectral remote sensing image and the field tree species survey verification sample points, and convert it into a 2M spatial resolution plant community raster map;

[0153] A construction unit 220 is used to obtain the optimal flooding time and critical flooding time of different types of plants based on the plant community type in each grid, and to construct an optimal flooding time grid map and a critical flooding time grid map with a spatial resolution of 2M;

[0154] The calculation unit 230 is used to extract DEM data with a spatial resolution of 1M in the study area based on the high-precision laser radar point cloud; based on the hyperspectral remote sensing image and the tide level data of the nearby tide gauge station, calculate the tidal height and flow rate at the key time nodes of the mangrove wetland in the study area according to the tidal type, season and daily variation law of the study area; calculate the daily average flooding time of the mangrove wetland at different elevations in four seasons, further obtain the annual daily average flooding time, and convert it into an annual average flooding time grid map with a spatial resolution of 2M in combination with the DEM data;

[0155] Evaluation unit 240 is used to compare and analyze the annual average flooding time, optimal flooding time and critical flooding time of the same grid unit based on a unified 2M spatial resolution, so as to determine the height suitability of mangrove plant growth in the study area.

[0156] As a preferred implementation, the calculation unit 230 includes:

[0157] The first determination subunit is used to determine the daily flooding time of the mangrove wetland at different elevations according to the tidal type, tidal height, flow velocity and tidal height time, and to construct a daily average flooding time grid map with a spatial resolution of 2M;

[0158] A calculation subunit, used for automatically calculating the average flooding time of each season according to the daily flooding time;

[0159] A subunit is constructed for calculating a grid map of annual average flooding duration based on the average flooding duration of each season.

[0160] When the tidal type is semi-diurnal, then:

[0161] v=(H high -H low ) / (T1-T2);

[0162] When n=0, D>H high , the corresponding daily flooding time is T = 0h;

[0163] When the elevation D is [H high -n*v,H high -(n-1)*v], the corresponding daily flooding time is T=n*2*2;

[0164] For example:

[0165] When n = 1, H high -1*v<D<H high , at this time the elevation D is [H high -1*v,H high ] The corresponding daily flooding time within the range is T=1*2*2=4;

[0166] When n = 2, H high -2*v<D<H high -1*v, height D in [H high -2*v,H high -1*v], the corresponding daily flooding time is T=2*2*2=8;

[0167] When n = 3, H high -3*v<D<H high -2*v, height D in [H high -3*v,H high -2*v], the corresponding daily flooding time is T=3*2*2=12;

[0168] When n = 4, H high -4*v<D<H high -3*v, elevation D in [H high-4*v,H high -3*v] The corresponding daily flooding time within this range is T=4*2*2=16;

[0169] …

[0170] When the height D <H low , the corresponding daily flooding time T = 24h.

[0171] Among them, H high Indicates the height of the tide at the highest point, H low represents the tide height at the lowest tide moment, T1 and T2 represent the time of the highest tide and the lowest tide respectively within 1 / 2 tidal cycle, n represents the duration of low tide (h); v represents the average tidal velocity of the day (cm / h), D represents the surface elevation of any point (cm), and T represents the flooding time of any point in the corresponding elevation range on the day.

[0172] As a preferred implementation, in the first aspect of the embodiment of the present invention,

[0173] When the tidal type is diurnal, then:

[0174] v=(H high -H low ) / (T1-T2);

[0175] When n=0, D>H high , the corresponding daily flooding time is T = 0h;

[0176] When the elevation D is [H high -n*v,H high -(n-1)*v], the corresponding daily flooding time is T=n*2;

[0177] For example:

[0178] When n = 1, H high -1*v<D<H high , at this time the elevation D is [H high -1*v,H high ] The corresponding daily flooding time within the range is T=1*2=2;

[0179] When n = 2, H high -2*v<D<H high -1*v, height D in [H high -2*v,H high -1*v], the corresponding daily flooding time is T=2*2=4;

[0180] When n = 3, H high -3*v<D<H high -2*v, height D in [Hhigh -3*v,H high -2*v], the corresponding daily flooding time is T=3*2=6;

[0181] When n = 4, H high -4*v<D<H high -3*v, elevation D in [H high -4*v,H high -3*v] The corresponding daily flooding time within this range is T=4*2=8;

[0182] …

[0183] When the height D <H low , the corresponding daily flooding time T = 24h;

[0184] Among them, H high Indicates the height of the tide at the highest point, H low represents the tide height at the lowest tide moment, T1 and T2 represent the time of the highest tide and the lowest tide respectively within 1 / 2 tidal cycle, n represents the duration of low tide (h); v represents the average tidal velocity of the day (cm / h), D represents the surface elevation of any point (cm), and T represents the flooding time of any point in the corresponding elevation range on the day.

[0185] As a preferred implementation, the evaluation unit 240 includes:

[0186] The second determination subunit is used to determine the upper limit and lower limit of the optimal flooding time and the critical flooding time in the grid unit of the study area according to the optimal flooding time and critical flooding time of the plant community type.

[0187] The third sub-unit is determined, and the average flooding duration in each grid unit of the study area is determined according to the annual average flooding duration grid map with a spatial resolution of 2M;

[0188] The fourth determination subunit is used to determine the suitability of the growth elevation of the mangrove plant community in the grid unit according to the upper limit of the optimal flooding time, the lower limit of the optimal flooding time, the critical flooding time and the annual average flooding time of the plant community in the grid unit.

[0189] The fourth determining subunit may further include:

[0190] When the average flooding duration in the target unit grid is less than the lower limit of the optimal flooding time of the plant community in the unit grid or the average flooding duration in the target unit grid is greater than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is not suitable for the growth of the mangrove plant;

[0191] When the average flooding duration of the target unit grid is greater than the upper limit of the optimal flooding time of the plant community of the unit grid and the average flooding duration of the target unit grid is less than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is more suitable for the growth of the mangrove plant;

[0192] When the average flooding duration of the target unit grid is greater than or equal to the lower limit of the optimal flooding time of the plant community and the average flooding duration of the target grid is less than or equal to the upper limit of the optimal flooding time of the plant community, then from the perspective of elevation, the target unit grid is very suitable for the growth of the mangrove plant.

[0193] Embodiment 3

[0194] See also Figure 5 , Figure 5 A schematic diagram of an electronic device that can be used to implement an embodiment of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the embodiments of the present invention described herein or / and claimed.

[0195] like Figure 5 As shown, the electronic device includes at least one processor 310, and a memory connected to the at least one processor 310, such as a ROM (read-only memory) 320, a RAM (random access memory) 330, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 310 can perform various appropriate actions and processes according to the computer program stored in the ROM 320 or the computer program loaded from the storage unit 380 to the random access memory RAM 330. In the RAM 330, various programs and data required for the operation of the electronic device can also be stored. The processor 310, the ROM 320, and the RAM 330 are connected to each other via a bus 340. An I / O (input / output) interface 350 is also connected to the bus 340.

[0196] A number of components in the electronic device are connected to the I / O interface 350, including: an input unit 360, such as a keyboard, a mouse, etc.; an output unit 370, such as various types of displays, speakers, etc.; a storage unit 380, such as a disk, an optical disk, etc.; and a communication unit 390, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 390 allows the electronic device to exchange information / data with other devices through a computer network such as the Internet or / and various telecommunication networks.

[0197] The processor 310 may be a variety of general or / and special processing components with processing and computing capabilities. Some examples of the processor 310 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 310 executes one or more steps of the method for evaluating the suitability of mangrove plant growth elevation based on the species level described in the first embodiment above.

[0198] In some embodiments, a method for evaluating the suitability of mangrove plant growth elevation based on the species level may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 380. In some embodiments, part or all of the computer program may be loaded into or / and installed on an electronic device via a ROM 320 and / or a communication unit 390. When the computer program is loaded into the RAM 330 and executed by the processor 310, one or more steps of the method for evaluating the suitability of mangrove plant growth elevation based on the species level described in the first embodiment above may be executed. Alternatively, in other embodiments, the processor 310 may be configured to execute a method for evaluating the suitability of mangrove plant growth elevation based on the species level by any other appropriate means (e.g., by means of firmware).

[0199] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, or / and combinations thereof. These various embodiments may include: being implemented in one or more computer programs that can be executed or / and interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, input device, and output device.

[0200] The computer programs for implementing the methods of the embodiments of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart or / and the block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0201] In the context of an embodiment of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, device, or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0202] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0203] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0204] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0205] The above is a detailed introduction to a method and device for evaluating the height suitability of mangrove plant growth based on the species level disclosed in the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A method for evaluating the suitability of mangrove plant growth elevation based on species level, characterized in that: It includes the following steps: Based on hyperspectral remote sensing images and field tree species survey verification sampling points, the plant community structure distribution map of the study area was obtained and converted into a plant community raster map with a spatial resolution of 2M; Based on the plant community type in each grid, the optimal flooding time and critical flooding time of different types of plants were obtained, and the optimal flooding time grid map and critical flooding time grid map with a spatial resolution of 2M were constructed. Based on high-precision LiDAR point cloud data, DEM data with a spatial resolution of 1M was extracted from the study area. Based on hyperspectral remote sensing images and tide data from nearby tide gauges, the tidal height and flow velocity at key time nodes of the mangrove wetlands in the study area were calculated according to the tidal type, season and daily variation of the study area. The daily average flooding time of the mangrove wetlands at different elevations in four seasons was calculated, and the annual daily average flooding time was further obtained, which was converted into an annual average flooding time raster map with a spatial resolution of 2M in combination with DEM data. Based on a unified 2M spatial resolution, the annual average flooding time, optimal flooding time, and critical flooding time of the same grid unit were compared and analyzed to determine the elevation suitability of mangrove plant growth in the study area. According to the tidal type, season and daily variation of the study area, the tidal height and flow velocity at key time nodes of the mangrove wetlands in the study area were calculated; the daily average flooding time of the mangrove wetlands at different elevations in four seasons was calculated, and the annual daily average flooding time was further obtained. Combined with the DEM data, it was converted into an annual average flooding duration raster map with a spatial resolution of 2M, including: Determine the daily flooding time of the mangrove wetland at different elevations according to the tidal type, tidal height, flow velocity and tidal height time, and construct a daily average flooding duration raster map with a spatial resolution of 2M; Automatically calculate the average flooding time in each season based on the daily flooding time; Calculate an annual average flooding duration raster map based on the average flooding duration of each season; When the tidal type is semi-diurnal, then: Tidal velocity v = (H high -H low ) / (T1-T2); Height D in [H high -n*v,H high -(n-1)*v], the corresponding daily flooding time is T=n*2*2; When the height D <H low , the corresponding daily flooding time T = 24h; When the elevation D>H high , the corresponding daily flooding time T = 0h; Among them, H high Indicates the height of the tide at the highest point, H low represents the tidal height at the lowest tide, T1 and T2 represent the highest and lowest tide times in a quarter of the tidal cycle, respectively, and n represents the duration of low tide (h); v represents the average tidal velocity of the day (cm / h), D represents the surface elevation of any point (cm), and T represents the flooding time of any point in the corresponding elevation range on the day; When the tidal type is diurnal, then: v=(H high -H low ) / (T1-T2); Height D in [H high -n*v,H high -(n-1)*v], the corresponding daily flooding time is T=n*2; When the height D <H low , the corresponding daily flooding time T = 24h; When the elevation D>H high , the corresponding daily flooding time T = 0h; Among them, H high Indicates the height of the tide at the highest point, H low represents the tide height at the lowest tide moment, T1 and T2 represent the time of the highest tide and the lowest tide respectively within 1 / 2 tidal cycle within 24 hours, n represents the duration of low tide (h); v represents the average tidal velocity of the day (cm / h), D represents the surface elevation of any point (cm), and T represents the flooding time of the day at any point in the corresponding elevation range.

2. The method for evaluating the suitability of mangrove plant growth elevation based on species level according to claim 1 is characterized in that: Based on a unified 2M spatial resolution, the annual average flooding time, optimal flooding time, and critical flooding time of the same grid unit were compared and analyzed to determine the elevation suitability of mangrove plant growth in the study area, including: According to the optimal flooding time and critical flooding time of plant community types, the upper limit and lower limit of the optimal flooding time and the critical flooding time in each grid unit of the study area were determined; Determine the average flooding duration in each grid cell of the study area based on the annual average flooding duration grid map with a spatial resolution of 2M; The suitability of the growth elevation of the mangrove plant community in the grid unit is determined based on the upper limit of the optimal flooding time, the lower limit of the optimal flooding time, the critical flooding time and the annual average flooding duration of the plant community in the grid unit.

3. The method for evaluating the suitability of mangrove plant growth elevation based on species level according to claim 2 is characterized in that: The suitability of the growth elevation of the mangrove plant community in the grid unit is determined based on the upper limit of the optimal flooding time, the lower limit of the optimal flooding time, the critical flooding time and the annual average flooding time of the plant community in the grid unit, including: When the average flooding duration in the target unit grid is less than the lower limit of the optimal flooding time of the plant community in the unit grid or the average flooding duration in the target unit grid is greater than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is not suitable for the growth of the mangrove plant; When the average flooding duration of the target unit grid is greater than the upper limit of the optimal flooding time of the plant community of the unit grid and the average flooding duration of the target unit grid is less than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is more suitable for the growth of the mangrove plant; When the average flooding duration of the target unit grid is greater than or equal to the lower limit of the optimal flooding time of the plant community and the average flooding duration of the target grid is less than or equal to the upper limit of the optimal flooding time of the plant community, then from the perspective of elevation, the target unit grid is very suitable for the growth of the mangrove plant.

4. A device for evaluating the suitability of mangrove plant growth elevation based on species level, characterized in that: It includes: The acquisition unit is used to verify the sample points based on hyperspectral remote sensing images and field tree species surveys, obtain the plant community structure distribution map of the study area, and convert it into a plant community raster map with a spatial resolution of 2M; A construction unit is used to obtain the optimal flooding time and critical flooding time of different types of plants based on the plant community type in each grid, and to construct an optimal flooding time grid map and a critical flooding time grid map with a spatial resolution of 2M; The calculation unit is used to extract DEM data with a spatial resolution of 1M in the study area based on high-precision lidar point cloud data; based on hyperspectral remote sensing images and tide data from nearby tide gauges, the tidal height and flow velocity at key time nodes of the mangrove wetlands in the study area are calculated according to the tidal type, season and daily variation of the study area; the daily average flooding time of the mangrove wetlands at different elevations in four seasons is calculated, and the annual daily average flooding time is further obtained, which is converted into an annual average flooding time raster map with a spatial resolution of 2M in combination with the DEM data; Evaluation unit, used to compare and analyze the annual average flooding time, optimal flooding time and critical flooding time of the same grid unit based on a unified 2M spatial resolution, so as to determine the height suitability of mangrove plant growth in the study area; Computing unit, including: Determine the daily flooding time of the mangrove wetland at different elevations according to the tidal type, tidal height, flow velocity and tidal height time, and construct a daily average flooding duration raster map with a spatial resolution of 2M; Automatically calculate the average flooding time in each season based on the daily flooding time; Calculate an annual average flooding duration raster map based on the average flooding duration of each season; When the tidal type is semi-diurnal, then: Tidal velocity v = (H high -H low ) / (T1-T2); Height D in [H high -n*v,H high -(n-1)*v], the corresponding daily flooding time is T=n*2*2; When the height D <H low , the corresponding daily flooding time T = 24h; When the elevation D>H high , the corresponding daily flooding time T = 0h; Among them, H high Indicates the height of the tide at the highest point, H low represents the tidal height at the lowest tide, T1 and T2 represent the highest and lowest tide times in a quarter of the tidal cycle, respectively, and n represents the duration of low tide (h); v represents the average tidal velocity of the day (cm / h), D represents the surface elevation of any point (cm), and T represents the flooding time of any point in the corresponding elevation range on the day; When the tidal type is diurnal, then: v=(H high -H low ) / (T1-T2); Height D in [H high -n*v,H high -(n-1)*v], the corresponding daily flooding time is T=n*2; When the height D <H low , the corresponding daily flooding time T = 24h; When the elevation D>H high , the corresponding daily flooding time T = 0h; Among them, H high Indicates the height of the tide at the highest point, H low represents the tide height at the lowest tide moment, T1 and T2 represent the time of the highest tide and the lowest tide respectively within 1 / 2 tidal cycle within 24 hours, n represents the duration of low tide (h); v represents the average tidal velocity of the day (cm / h), D represents the surface elevation of any point (cm), and T represents the flooding time of the day at any point in the corresponding elevation range.

5. The device for evaluating the suitability of mangrove plant growth elevation based on species level according to claim 4 is characterized in that: The evaluation unit comprises: The second determination subunit is used to determine the upper limit of the optimal flooding time, the lower limit of the optimal flooding time, and the critical flooding time in the grid unit of the study area according to the optimal flooding time and the critical flooding time of the plant community type respectively; The third sub-unit is determined, and the average flooding duration in each grid unit of the study area is determined according to the annual average flooding duration grid map with a spatial resolution of 2M; The fourth determination subunit is used to determine the suitability of the growth elevation of the mangrove plant community in the grid unit according to the upper limit of the optimal flooding time, the lower limit of the optimal flooding time, the critical flooding time and the annual average flooding time of the plant community in the grid unit.

6. The device for evaluating the suitability of mangrove plant growth elevation based on species level according to claim 5, characterized in that: The fourth determining subunit includes: When the average flooding duration in the target unit grid is less than the lower limit of the optimal flooding time of the plant community in the unit grid or the average flooding duration in the target unit grid is greater than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is not suitable for the growth of the mangrove plant; When the average flooding duration of the target unit grid is greater than the upper limit of the optimal flooding time of the plant community of the unit grid and the average flooding duration of the target unit grid is less than the critical flooding time of the plant community, then from the perspective of elevation, the target unit grid is more suitable for the growth of the mangrove plant; When the average flooding duration of the target unit grid is greater than or equal to the lower limit of the optimal flooding time of the plant community and the average flooding duration of the target grid is less than or equal to the upper limit of the optimal flooding time of the plant community, then from the perspective of elevation, the target unit grid is very suitable for the growth of the mangrove plant.

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