Analysis and evaluation method suitable for coral reef area landscape pattern

Abstract

The invention provides an analysis and evaluation method suitable for a coral reef area landscape pattern, and belongs to the technical field of coral reef areas, and the method comprises the following steps: (1) laying a short-term monitoring quadrat or a long-term monitoring quadrat according to actual needs, and determining the length of the quadrat according to underwater transparency; (2) shooting a high-definition picture of a substrate landscape in the quadrat along the length direction of the quadrat; (3) correcting and splicing the pictures through gis or CAD software, and interpreting the species of the coral reef according to the spliced quadrat pictures; and (4) calculating a landscape pattern index to judge the condition of the coral reef habitat landscape pattern. The two kinds of quadrats can make up for the problem that a transect method cannot record landscape plaques in detail, the problems that original large quadrats are fuzzy in shooting and inconvenient to move can be solved, small quadrats divided in the two quadrats are shot one by one, the types of substrates such as coral reef plaques can be clearly reflected, seamless splicing between the small quadrats is facilitated, and the method is suitable for large-scale popularization and application. Errors are reduced, and large-area landscape pattern research can be carried out.

Description

Technical Field

[0001] The present invention relates to the technical field of coral reef areas, and in particular to an analysis and evaluation method suitable for the landscape pattern of coral reef areas. Background Art

[0002] Currently, the main methods for monitoring coral reefs are: one is the line transect method, which records the substrate type at measurement points 10 cm apart along the transect to analyze species ratios, coral mortality rates, and rock-to-sand ratios within the transect. Due to limitations in its operation, this line transect method only collects point-like data on the substrate. Images taken along the transect lack vertical transect control, making it difficult to accurately calculate the area of ​​each geological feature. Another method, the sampling method, is used to monitor coral growth, typically using larger plots, such as 2m*2m or 5m*5m. These plots are difficult to capture a clear, panoramic view and are often left on the seafloor for years, making them difficult to move for monitoring large underwater areas or transport aboard ships to change survey areas. However, studies of coral reef landscape patterns typically require imaging, analyzing, and counting the substrate, including coral patches, over large areas. Existing coral reef monitoring methods are technically incapable of studying landscape patterns over such large areas. Therefore, a suitable analytical and evaluation method for coral reef landscape patterns is needed. Summary of the Invention

[0003] The purpose of this invention is to provide a method for analyzing and evaluating the landscape patterns of coral reef areas, addressing the technical problem of existing coral reef monitoring methods that prevents them from studying landscape patterns over large areas. By designing short-term monitoring plots (movable plots) and long-term monitoring plots (fixed plots), combined with high-definition image stitching and landscape index calculation, this method significantly improves the accuracy and efficiency of coral reef habitat monitoring.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is as follows: A method for analyzing and evaluating the landscape pattern of coral reef areas includes the following steps: (1) Arrange short-term monitoring plots or long-term monitoring plots according to actual needs, and determine the plot length based on underwater transparency; (2) Take high-definition pictures of the bottom landscape along the length of the sample plot; (3) Use GIS or CAD software to correct and stitch the images, and identify the species of coral reefs based on the stitched quadrat images; (4) Calculate the landscape pattern index to determine the status of the coral reef habitat landscape pattern.

[0005] Furthermore, in step (1), the short-term monitoring sample plot is composed of a steel wire rope with a colored plastic-coated line, and the intersection of the sample plot is fixed with stainless steel screws at intervals of 50 cm on the plastic-coated line. The total length of the sample plot is set to 5 m or 10 m, and the width is set to 80 cm. Furthermore, the diameter of the steel wire rope is set to 5 mm and is made of 304 stainless steel.

[0006] Furthermore, in step (1), the long-term monitoring sample plot is composed of a hollow thick-walled tube, and the intersection of the sample plot is fixed with stainless steel screws at intervals of 50 cm on the plastic-coated line. The total length of the sample plot is set to 5 m or 10 m, and the width is set to 50 cm. Furthermore, the outer diameter of the hollow thick-walled tube is set to 5 mm or 6 mm, and is made of 304 stainless steel.

[0007] Furthermore, in step (2), the specific process of shooting is as follows: the underwater layout direction of the sample plot is arranged in the length direction, the length direction of the sample plot is parallel to the coastline, and it is spread flat on the coral reef area on the seabed, and then a camera is used to take high-definition pictures of each sample plot.

[0008] Furthermore, in step (3), the specific process of image correction and stitching is: first, use Gis or CAD software to import underwater images and correct them; then stitch the images; finally, interpret and outline the type and range of the underwater bottom landscape based on the stitched images and calculate the area.

[0009] Furthermore, in step (4), the calculation method of the landscape pattern index is: (1) Calculate the total landscape area (TA) Where Ai is the area of ​​a certain type of landscape, i is the landscape category, and m is the total number of landscapes.

[0010] (2) Calculation of landscape diversity index (H) Where, P k is the ratio of k landscape types to the total area, and m is the total number of landscape types in the study area.

[0011] (3) Calculation of the average plaque fractal dimension index (D) Where, P i is the perimeter of a single patch of landscape type i, a i is the area of ​​a single patch of landscape type i, N is the number of patches of landscape type i, D is the fractal dimension of landscape type i, and n is the total number of patches of landscape type i.

[0012] (4) Calculation of dominance index (D0) Where H max is the diversity index when the proportions of various types of landscapes in the study area are equal, that is, the maximum diversity index. ;P k is the ratio of k landscape types to the total area, and m is the total number of landscape types.

[0013] (5) Calculate the uniformity index (E) Where H is the landscape diversity index, H max It is the diversity index when the proportions of various types of landscapes in the study area are equal, that is, the maximum diversity index.

[0014] (6) Calculation of plaque density index (PD) Where PD is the total density of landscape patches, NP is the total number of landscape patches; A is the total area of ​​the landscape; PD is the total density of landscape patches, NP is the total number of landscape patches, A is the total area of ​​the landscape; i is the density of landscape patch type i, NP i is the total number of landscape patches of type i.

[0015] The present invention has the following beneficial effects due to the adoption of the above technical solution: The two sample plots of the present invention can both make up for the problem that the sample line method cannot record landscape patches in detail, and can solve the problem that the original large sample plot is blurry and inconvenient to move. Moreover, the small sample plots separated from the two sample plots are photographed one by one, which can clearly reflect the bottom types such as coral reef patches, and facilitate seamless splicing between small sample plots, reducing errors, and solving the technical problem that the existing methods of coral reef monitoring cannot conduct research on landscape patterns of large areas.

[0016] In the present invention, the split sample design supports large-scale seamless splicing, improving the spatial continuity of data; the lightweight short-term sample is easy to move, and the fixed long-term sample is highly corrosion-resistant; by combining high-definition images with landscape indexes, the accuracy of coral reef habitat assessment is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of a short-term monitoring quadrat of the present invention; Figure 2 is a schematic diagram of a long-term monitoring quadrat of the present invention; Figure 3 It is a schematic diagram of image correction by GIS or CAD software of the present invention; Figure 4It is a schematic diagram of image splicing using GIS or CAD software of the present invention. DETAILED DESCRIPTION

[0018] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and by way of preferred embodiments. However, it should be noted that many of the details listed in this specification are merely provided to help the reader gain a thorough understanding of one or more aspects of the present invention, and these aspects of the present invention can be practiced even without these specific details.

[0019] like Figure 1-4 As shown in FIG, a method for analyzing and evaluating the landscape pattern of coral reef areas includes the following steps: (1) Arrange short-term monitoring plots or long-term monitoring plots according to actual needs, and determine the plot length based on underwater transparency; If short-term monitoring surveys are required in the monitoring area, lightweight and portable materials and a frame structure can be used to facilitate underwater deployment and recovery at multiple measurement points. The short-term monitoring plots are constructed from colored plastic-coated steel wire ropes. The intersections of the plots are secured to the plastic-coated ropes at 50 cm intervals using stainless steel screws. The total plot length is set to 5m or 10m (determined based on local underwater clarity) and the width is set to 80cm. The steel wire ropes are 5mm in diameter and made of 304 stainless steel for excellent corrosion resistance.

[0020] If the monitoring area is to be monitored for long-term surveys, the sample plot is often fixed to the seabed. These long-term monitoring plots consist of hollow, thick-walled tubes. The intersections of the plots are fixed to the plastic-coated lines at 50 cm intervals using stainless steel screws. The total length of the plot is set to 5 or 10 meters (the total horizontal length of the plot can be determined based on local underwater clarity) and the width is set to 50 cm. The outer diameter of the hollow, thick-walled tubes is 5 or 6 mm and is made of 304 stainless steel for excellent corrosion resistance.

[0021] (2) Take high-definition pictures of the bottom landscape along the length of the sample plot; The specific process of shooting is as follows: the underwater layout direction of the sample plot is arranged in the length direction, the length direction of the sample plot is parallel to the coastline, and it is spread flat on the coral reef area on the seabed, and then a camera is used to take high-definition pictures of each sample plot.

[0022] (3) Use GIS or CAD software to correct and stitch the images, and identify the species of coral reefs based on the stitched quadrat images; The specific process of image correction and stitching is: first use Gis or CAD software to import underwater images and correct them; then stitch the images; finally, interpret and outline the type and range of the underwater bottom landscape based on the stitched images and calculate the area.

[0023] (4) Calculate the landscape pattern index to determine the status of the coral reef habitat landscape pattern.

[0024] The calculation method of landscape pattern characteristics is used for analysis, and the status of the coral reef habitat landscape pattern is judged based on the landscape index.

[0025] The calculation method of landscape pattern index is: (1) Calculate the total landscape area (TA) Where Ai is the area of ​​a certain type of landscape, i is the landscape category, and m is the total number of landscapes.

[0026] (2) Calculation of landscape diversity index (H) Where, P k is the ratio of k landscape types to the total area, and m is the total number of landscape types in the study area.

[0027] (3) Calculation of the average plaque fractal dimension index (D) Where, P i is the perimeter of a single patch of landscape type i, a i is the area of ​​a single patch of landscape type i, N is the number of patches of landscape type i, D is the fractal dimension of landscape type i, and n is the total number of patches of landscape type i.

[0028] (4) Calculation of dominance index (D0) Where H max is the diversity index when the proportions of various types of landscapes in the study area are equal, that is, the maximum diversity index. ;P k is the ratio of k landscape types to the total area, and m is the total number of landscape types.

[0029] (5) Calculate the uniformity index (E) Where H is the landscape diversity index, H max It is the diversity index when the proportions of various types of landscapes in the study area are equal, that is, the maximum diversity index.

[0030] (6) Calculation of plaque density index (PD) Where PD is the total density of landscape patches, NP is the total number of landscape patches; A is the total area of ​​the landscape; PD is the total density of landscape patches, NP is the total number of landscape patches, A is the total area of ​​the landscape; i is the density of landscape patch type i, NP i is the total number of landscape patches of type i.

[0031] Example 1 The analysis and evaluation method of the present invention was used to monitor and calculate the coral reef area in the southwest waters of Weizhou Island, Beihai City, Guangxi Zhuang Autonomous Region. The results are as follows: The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for analyzing and evaluating the landscape pattern of coral reef areas, characterized by: The following steps are involved: (1) Arrange short-term monitoring plots or long-term monitoring plots according to actual needs, and determine the plot length based on underwater transparency; (2) Take high-definition pictures of the bottom landscape along the length of the sample plot; (3) Use GIS or CAD software to correct and stitch the images, and identify the species of coral reefs based on the stitched quadrat images; (4) Calculate the landscape pattern index to determine the status of the coral reef habitat landscape pattern.

2. The method for analyzing and evaluating the landscape pattern of a coral reef area according to claim 1, wherein: In step (1), the short-term monitoring sample plot is composed of a steel wire rope with a colored plastic-coated line. The intersection of the sample plot is fixed with stainless steel screws at intervals of 50 cm on the plastic-coated line. The total length of the sample plot is set to 5 m or 10 m, and the width is set to 80 cm.

3. The method for analyzing and evaluating the landscape pattern of a coral reef area according to claim 2, wherein: The diameter of the steel wire rope is set to 5mm and is made of 304 stainless steel.

4. The method for analyzing and evaluating the landscape pattern of a coral reef area according to claim 1, wherein: In step (1), the long-term monitoring sample plot is composed of a hollow thick-walled tube, and the intersection of the sample plot is fixed with stainless steel screws at intervals of 50 cm on the plastic-coated line. The total length of the sample plot is set to 5 m or 10 m, and the width is set to 50 cm.

5. The method for analyzing and evaluating the landscape pattern of a coral reef area according to claim 4, characterized in that: The outer diameter of the hollow thick-walled tube is set to 5mm or 6mm, and is made of 304 stainless steel.

6. The method for analyzing and evaluating the landscape pattern of a coral reef area according to claim 1, characterized in that: In step (2), the specific process of shooting is as follows: the underwater layout direction of the sample plot is arranged in the length direction, the length direction of the sample plot is parallel to the coastline, and it is spread flat on the coral reef area on the seabed, and then a camera is used to take high-definition pictures of each sample plot.

7. The method for analyzing and evaluating the landscape pattern of a coral reef area according to claim 1, characterized in that: In step (3), the specific process of image correction and stitching is: first use Gis or CAD software to import underwater images and correct them; then stitch the images; finally, interpret and outline the type and range of the underwater bottom landscape based on the stitched images and calculate the area.

8. The method for analyzing and evaluating the landscape pattern of a coral reef area according to claim 1, characterized in that: In step (4), the calculation method of landscape pattern index is: (1) Calculate the total landscape area (TA) Where Ai is the area of ​​a certain type of landscape, i is the landscape category, and m is the total number of landscapes. (2) Calculation of landscape diversity index (H) Where, P k is the ratio of k landscape types to the total area, and m is the total number of landscape types in the study area. (3) Calculation of average plaque fractal dimension index (D) Where, P i is the perimeter of a single patch of landscape type i, a i is the area of ​​a single patch of landscape type i, N is the number of patches of landscape type i, D is the fractal dimension of landscape type i, and n is the total number of patches of landscape type i. (4) Calculation of dominance index (D0) Where H max is the diversity index when the proportions of various types of landscapes in the study area are equal, that is, the maximum diversity index. ;P k is the ratio of k landscape types to the total area, and m is the total number of landscape types. (5) Calculate the uniformity index (E) Where H is the landscape diversity index, H max It is the diversity index when the proportions of various types of landscapes in the study area are equal, that is, the maximum diversity index. (6) Calculation of plaque density index (PD) Where PD is the total density of landscape patches, NP is the total number of landscape patches; A is the total area of ​​the landscape; PD is the total density of landscape patches, NP is the total number of landscape patches, A is the total area of ​​the landscape; i is the density of landscape patch type i, NP i is the total number of landscape patches of type i.

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