A method for optimizing the layout of observation points for biodiversity survey

Abstract

The invention relates to the technical field of observation point layout, and specifically discloses an observation point layout optimization method for biodiversity survey, comprising the following steps: step S1: obtaining a plane image of an ecological region, setting a resolution and a side length, dividing a grid according to the resolution and marking intersections as observation points; selecting a sub-region and numbering the observation points, setting an observation period and nodes, and collecting historical observation data; step S2: setting fluctuation constraints according to historical data, calculating a biomass difference threshold, and judging whether there is fluctuation in biomass in the sub-region; counting the number of fluctuation nodes to determine whether adjustment is required; step S3: recording fluctuation nodes for the region that needs adjustment, and calculating an adjustment amount according to the biomass; the adjustment amount is obtained by the biomass average value and a correction coefficient of each observation point under the fluctuation node; evaluating the fluctuation of biomass by analyzing historical data, and adjusting the setting of observation points accordingly to obtain more accurate biodiversity data.

Description

Technical Field

[0001] The invention relates to the technical field of observation point layout, and in particular to an observation point layout optimization method for biodiversity survey. Background Art

[0002] A biodiversity survey is a systematic study of species diversity, genetic diversity and ecosystem diversity in an ecosystem, aiming to assess the status, trends and impacts of human activities on biodiversity; biodiversity surveys are generally conducted in ecosystems that contain a large number of organisms, such as wetlands, forests and grasslands.

[0003] The layout of observation points for biodiversity surveys is a very important part of the biodiversity survey process. When laying out observation points for biodiversity surveys, we must not only consider technical specifications and monitoring objectives, but also respond to various challenges and adopt effective strategies to optimize the observation network to ensure the scientificity and effectiveness of the data.

[0004] When setting up observation points in an ecosystem, the grid method is usually used to divide the ecosystem into several survey grids, which are set up according to a certain resolution (for example, 10 km × 10 km). However, in the same ecosystem, the species complexity in different areas is different. For example, the soil nutrients and humidity in different areas are different, which makes the biomass in different areas different. The fixed grid observation points in the existing technology cannot comprehensively observe the biological conditions of the ecosystem in different areas. Summary of the invention

[0005] The purpose of the present invention is to provide a method for optimizing the layout of observation points for biodiversity survey to solve the above technical problems.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A method for optimizing the layout of observation points for biodiversity survey, comprising the following steps:

[0008] Step S1: Obtain an ecological region plane image, divide the ecological region plane image into grids, and obtain f 1 *f 2 The grid, where f 1 *f 2 Indicates the preset initial resolution, obtains the actual coordinate points corresponding to the intersection points in the grid, and records them as observation points; sets the side length of the region, selects several rectangular sub-regions in the grid, and numbers the observation points in the sub-regions;

[0009] An observation period is set, and a number of observation nodes are selected at equal intervals during the observation period; historical observation data are obtained, wherein the historical observation data includes the biomass at each observation point at different observation nodes;

[0010] Step S2: According to the historical observation data, set the fluctuation constraint |B i -B i-1 |≥μ, where B i is the biomass at the ith observation point at the observation node, μ is the difference threshold; if there is an observation point that satisfies the fluctuation constraint, then the observation point Wave(B i , B i-1 )=1; if not satisfied, then record the observation point Wave(B i , B i-1 )=0;

[0011] If each observation point in the sub-region exists Where n is the total number of observation points in the sub-region, z is the preset score threshold, and z>1, then it is recorded that there is fluctuation in biomass in the sub-region;

[0012] Obtain the total number m of observation nodes, and obtain the number num of observation nodes in each observation node where the biomass of the sub-region fluctuates. If num≥m / z, the sub-region is recorded as a region to be adjusted;

[0013] Step S3: Obtain the observation nodes where the area to be adjusted has fluctuations, recorded as fluctuation nodes; obtain the adjustment amount according to the biomass at each observation point in the sub-area under the fluctuation node Where N is the total number of fluctuation nodes, B ave is the average value of the biomass at each observation point in the sub-area, ε is a preset correction coefficient and ε>0; the initial resolution of the area to be adjusted is adjusted according to the adjustment amount.

[0014] As a further solution of the present invention: the process of selecting the sub-region includes:

[0015] A rectangular selection area is established according to the side length of the area, an inflection point at any corner of the grid is selected, any vertex of the rectangular selection area is made to coincide with the inflection point, and the first sub-area is selected; and the rectangular selection area is translated upward or downward or left or right by a distance d, and several sub-areas are selected in turn, where d is the side length of the area.

[0016] As a further solution of the present invention: the process of determining the observation points in the sub-area includes:

[0017] For each sub-region within the grid, obtain all intersection points inside the sub-region, and obtain all intersection points on the left and top sides, and record them as observation points of the sub-region; if there is no adjacent sub-region below or to the right of the sub-region, obtain all intersection points on the bottom or right side of the sub-region, and record them as observation points of the sub-region.

[0018] As a further solution of the present invention: the selection process of the observation node includes the starting point and the end point of the observation period.

[0019] As a further solution of the present invention: the process of obtaining the difference threshold value includes:

[0020] All observation points in the grid are renumbered to obtain the biomass between each two adjacent numbered observation points, which are recorded as B1 and B2 respectively, and the biomass difference CB = |B1-B2| is obtained; then the mean difference in the grid is obtained CB e is the e-th biomass difference; then the average value of the difference mean of the grid under each observation node is obtained CB ave-g is the difference mean of the grid under the g-th observation node; then the difference threshold μ=CB′.

[0021] As a further solution of the present invention: if the number of observation nodes num<m / z where the biomass of the sub-region fluctuates, the initial resolution of the sub-region is not adjusted.

[0022] As a further solution of the present invention: the process of adjusting the initial resolution of the area to be adjusted includes: obtaining the final resolution of the area to be adjusted as Mf according to the initial resolution and the adjustment amount. 1 *Mf 2 .

[0023] As a further solution of the present invention: if M≤1, the initial resolution of the sub-region is not adjusted.

[0024] Beneficial effects of the present invention:

[0025] When setting up observation points in an ecosystem, the grid method is usually used to divide the ecosystem into several survey grids, which are set up according to a certain resolution (for example, 10 km × 10 km). However, in the same ecosystem, the species complexity in different areas is different. For example, the soil nutrients and humidity in different areas are different, which makes the biomass in different areas different. The fixed grid observation points in the existing technology cannot comprehensively observe the biological conditions of the ecosystem in different areas.

[0026] Compared with the prior art, the present invention obtains the plane image information of the ecological region, sets the initial resolution and the side length of the region, divides the plane image of the ecological region into grids and marks the intersections as observation points; by numbering the observation points in the sub-region and setting the observation period, a number of observation nodes are selected to obtain historical observation data; according to the historical data, fluctuation constraints are set to determine whether there is fluctuation in the biomass in the sub-region, and the number of fluctuation nodes is counted; for areas that need to be adjusted, the fluctuation nodes are recorded and the adjustment amount is calculated based on the biomass; this optimization method can more accurately evaluate the fluctuation of biomass, and adjust the setting of observation points accordingly to obtain more accurate biodiversity data. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will be further described below in conjunction with the accompanying drawings.

[0028] Figure 1 It is a flow chart of an optimization method for setting up observation points for biodiversity survey according to the present invention. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0030] See also Figure 1 As shown, the present invention is a method for optimizing the layout of observation points for biodiversity survey, comprising the following steps:

[0031] Step S1: Obtain an ecological region plane image, divide the ecological region plane image into grids, and obtain f 1 *f 2 The grid, where f 1 *f 2 Indicates the preset initial resolution, obtains the actual coordinate points corresponding to the intersection points in the grid, and records them as observation points; sets the side length of the region, selects several rectangular sub-regions in the grid, and numbers the observation points in the sub-regions;

[0032] An observation period is set, and a number of observation nodes are selected at equal intervals during the observation period; historical observation data are obtained, wherein the historical observation data includes the biomass at each observation point at different observation nodes;

[0033] It is understandable that the setting of the initial resolution needs to be determined according to the actual situation and research requirements. 1 =f 2, then the grid obtained after grid division is square; Different research objectives may require resolutions at different scales. For example, a larger grid unit may be used for research on large animals, while a finer division may be required for research on small organisms or plant communities. Species with low mobility or a narrow distribution range may require smaller grid units to more accurately capture their distribution; for example, in some forest ecosystem studies, a 100m x 100m grid unit is used for investigation;

[0034] It should be noted that the setting of the observation period depends on multiple factors, including research objectives, life history characteristics of organisms, seasonal changes, climate change, resource availability and duration of the project; different species have different life histories and behavioral patterns, which determine their activities and distribution on different time scales; for example, for migratory birds, cross-seasonal observation periods may be required to capture their migration patterns; in addition, the biodiversity of many ecosystems shows strong seasonal changes, especially in temperate regions; in these cases, the observation period may need to be arranged around specific seasons or climate conditions to ensure the representativeness of the data;

[0035] As a preferred embodiment of the present invention, the sub-region selection process includes:

[0036] A rectangular selection area is established according to the side length of the area, an inflection point at any corner of the grid is selected, any vertex of the rectangular selection area is overlapped with the inflection point, and the first sub-area is selected; and the rectangular selection area is translated upward or downward or left or right by a distance d, and several sub-areas are selected in sequence, where d is the side length of the area;

[0037] It is understandable that the sub-region is a square and the setting of the side length of the region must satisfy the constraint Where N + is a set of positive integers to ensure that the sizes of each sub-region are consistent;

[0038] As a preferred embodiment of the present invention, the process of determining the observation points in the sub-area includes:

[0039] For each sub-region in the grid, obtain all the intersection points inside the sub-region, and obtain all the intersection points on the left and top sides, and record them as observation points of the sub-region; if there is no adjacent sub-region below or to the right of the sub-region, obtain all the intersection points on the bottom or right side of the sub-region, and record them as observation points of the sub-region;

[0040] It can be understood that there are overlapping edges between the sub-regions in the grid, and the above steps ensure that there is no duplication in the inclusion of observation points between sub-regions, and no observation points at the boundary of the plane image of the ecological region are omitted;

[0041] As a preferred embodiment of the present invention, the selection process of the observation node includes the starting point and the end point of the observation period;

[0042] It should be noted that the selection of the observation nodes is based on a preset time interval; the setting of the time interval depends on the ecological process, such as the growth period of plants or the hibernation period of animals, and a specific observation time interval may be required to accurately record these changes;

[0043] Step S2: According to the historical observation data, set the fluctuation constraint |B i -B i-1 |≥μ, where B i is the biomass at the ith observation point at the observation node, μ is the difference threshold; if there is an observation point that satisfies the fluctuation constraint, then the observation point Wave(B i , B i-1 )=1; if not satisfied, then record the observation point Wave(B i , B i-1 )=0;

[0044] If each observation point in the sub-region exists Where n is the total number of observation points in the sub-region, z is the preset score threshold, and z>1, then it is recorded that there is fluctuation in biomass in the sub-region;

[0045] Obtain the total number m of observation nodes, and obtain the number num of observation nodes in each observation node where the biomass of the sub-region fluctuates. If num≥m / z, the sub-region is recorded as a region to be adjusted;

[0046] It can be understood that by comparing the biomass difference between consecutive observation points with the preset difference threshold μ, it is judged whether there is a significant fluctuation in biomass. If the difference is greater than or equal to the threshold, it is considered that the fluctuation is significant; if it is less than the threshold, it is considered that the fluctuation is not significant; for a series of observation points in a sub-region, if there is a certain proportion of observation points with significant biomass difference (i.e., satisfying the fluctuation constraint condition), it is considered that there is a fluctuation in biomass in the entire sub-region; if a certain proportion of sub-regions in the observation nodes are judged to have fluctuations in biomass, these sub-regions are regarded as areas to be adjusted;

[0047] As a preferred embodiment of the present invention, the process of obtaining the difference threshold includes:

[0048] All observation points in the grid are renumbered to obtain the biomass between each two adjacent numbered observation points, which are recorded as B1 and B2 respectively, and the biomass difference CB = |B1-B2| is obtained; then the mean difference in the grid is obtained CB eis the e-th biomass difference; then the average value of the difference mean of the grid under each observation node is obtained CB ave-g is the difference mean of the grid under the g-th observation node; then the difference threshold μ=CB′;

[0049] It can be understood that the difference threshold is used to evaluate whether the change of biomass in the plane image of the ecological region is significant. It is obtained based on the statistical characteristics of the actual observation data and is the average value of the biomass difference of adjacent observation points under all observation nodes, which serves as a standard for judging whether the biomass fluctuation is within the normal range;

[0050] As a preferred embodiment of the present invention, if the number of observation nodes num of fluctuations in the biomass of the sub-region is less than m / z, the initial resolution of the sub-region is not adjusted;

[0051] It can be understood that if num < m / z, that is, the number of observation nodes with biomass fluctuations is less than the threshold, the initial resolution of the sub-region is considered sufficient and no adjustment is required; if num ≥ m / z, that is, the number of observation nodes with biomass fluctuations is greater than or equal to the threshold, the initial resolution of the sub-region may need to be adjusted to better capture ecological changes;

[0052] Step S3: Obtain the observation nodes where the area to be adjusted has fluctuations, recorded as fluctuation nodes; obtain the adjustment amount according to the biomass at each observation point in the sub-area under the fluctuation node Where N is the total number of fluctuation nodes, B ave is the average value of the biomass at each observation point in the sub-area, ε is a preset correction coefficient and ε>0; the initial resolution of the area to be adjusted is adjusted according to the adjustment amount;

[0053] Understandably, It is the standard deviation of the biomass of each observation point in the sub-region under the fluctuation node, reflecting the average degree of deviation of the biomass of each observation point in the sub-region under the fluctuation node from the mean, and reflecting the overall fluctuation of the data set; the greater the fluctuation, the greater the difference in biomass between the observation points in the sub-region under the fluctuation node, and more detailed observation points are needed;

[0054] As a preferred embodiment of the present invention, the process of adjusting the initial resolution of the area to be adjusted includes: obtaining the final resolution of the area to be adjusted as Mf according to the initial resolution and the adjustment amount. 1 *Mf 2 ;

[0055] If M≤1, the initial resolution of the sub-region is not adjusted;

[0056] It can be understood that the adjustment amount is derived based on the change in biomass and a preset correction coefficient, and is used to guide the adjustment of resolution; if M≤1, it indicates that the existing initial resolution is sufficient and no adjustment is required; this is because the adjustment amount is less than or equal to 1, which means that the change in biomass is within an acceptable range and there is no need to increase the resolution to capture more subtle changes; if M>1, the initial resolution needs to be adjusted, and the final resolution is the product of the initial resolution and the adjustment amount.

[0057] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A method for optimizing the layout of observation points for biodiversity survey, characterized in that: The following steps are involved: Step S1: obtaining a plane image of the ecological region, dividing the plane image of the ecological region into grids, obtaining a grid of f1*f2, wherein f1*f2 represents a preset initial resolution, obtaining actual coordinate points corresponding to intersection points in the grid, and recording them as observation points; Set the side length of the region, select several rectangular sub-regions in the grid, and number the observation points in the sub-regions; An observation period is set, and a number of observation nodes are selected at equal intervals during the observation period; historical observation data are obtained, wherein the historical observation data includes the biomass at each observation point at different observation nodes; Step S2: According to the historical observation data, set the fluctuation constraint |B i -B i-1 |≥μ, where B i is the biomass at the ith observation point at the observation node, μ is the difference threshold; if there is an observation point that satisfies the fluctuation constraint, then the observation point Wave(B i , B i-1 )=1; if not satisfied, then record the observation point Wave(B i , B i-1 )=0; If each observation point in the sub-region exists , where n is the total number of observation points in the sub-region, z is the preset score threshold, and z>1, then it is recorded that the biomass in the sub-region fluctuates; Obtain the total number m of observation nodes, and obtain the number num of observation nodes in each observation node where the biomass of the sub-region fluctuates. If num≥m / z, the sub-region is recorded as a region to be adjusted; Step S3: Obtain the observation nodes where the area to be adjusted has fluctuations, recorded as fluctuation nodes; obtain the adjustment amount according to the biomass at each observation point in the sub-area under the fluctuation node , where N is the total number of fluctuation nodes, B ave is the average value of the biomass at each observation point in the sub-area, ε is a preset correction coefficient and ε>0; the initial resolution of the area to be adjusted is adjusted according to the adjustment amount.

2. The method for optimizing the layout of observation points for biodiversity survey according to claim 1, characterized in that: In step S1, the sub-region selection process includes: A rectangular selection area is established according to the side length of the area, an inflection point at any corner of the grid is selected, any vertex of the rectangular selection area is made to coincide with the inflection point, and the first sub-area is selected; and the rectangular selection area is translated upward or downward or left or right by a distance d, and several sub-areas are selected in turn, where d is the side length of the area.

3. The method for optimizing the layout of observation points for biodiversity survey according to claim 1, characterized in that: In step S1, the process of determining the observation points in the sub-area includes: For each sub-region within the grid, obtain all intersection points inside the sub-region, and obtain all intersection points on the left and top sides, and record them as observation points of the sub-region; if there is no adjacent sub-region below or to the right of the sub-region, obtain all intersection points on the bottom or right side of the sub-region, and record them as observation points of the sub-region.

4. The method for optimizing the layout of observation points for biodiversity survey according to claim 1, characterized in that: In step S1, the selection process of the observation node includes the starting point and the end point of the observation period.

5. The method for optimizing the layout of observation points for biodiversity survey according to claim 1, characterized in that: In step S2, if the number of observation nodes num<m / z where the biomass of the sub-region fluctuates, the initial resolution of the sub-region is not adjusted.

6. The method for optimizing the layout of observation points for biodiversity survey according to claim 1, characterized in that: In step S3, the process of adjusting the initial resolution of the area to be adjusted includes obtaining the final resolution of the area to be adjusted as Mf1*Mf2 according to the initial resolution and the adjustment amount.

7. The method for optimizing the layout of observation points for biodiversity survey according to claim 6, characterized in that: In step S3, if M≤1, the initial resolution of the sub-region is not adjusted.

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