A method and device for automatically delineating a watershed control unit that bridges administrative boundaries

Abstract

The application provides a watershed control unit automatic demarcation method and device connecting administrative boundaries, relates to the field of watershed division, and comprises the following steps: obtaining initial DEM data and administrative division planar vector data of a target region, constructing a buffer zone according to the administrative division planar vector data, and obtaining final DEM data by clipping the initial DEM data according to the buffer zone; presetting a cumulative flow threshold and a minimum watershed area of the target region, constructing and optimizing a natural watershed vector plane according to the final DEM data, the cumulative flow threshold and the minimum watershed area, and obtaining optimized natural watershed vector plane data; superimposing and calculating the fitting degree of the administrative division planar vector data and the optimized natural watershed vector plane data, and obtaining a preliminary watershed control unit; optimizing the preliminary watershed control unit according to the minimum watershed area, and obtaining a final watershed control unit; and giving fields to the final watershed control unit according to the administrative division planar vector data, and obtaining a demarcation result of the natural watershed and the administrative boundary.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of watershed division, and in particular to a method and device for automatically dividing a watershed control unit that connects administrative boundaries. BACKGROUND

[0002] The existing watershed division method mainly includes two methods. The first method is to realize automatic natural watershed division based on DEM data and a model constructor. The main process includes a DEM preprocessing stage: using a dynamic value limiting algorithm to eliminate the depressions in the DEM data; a hydrological analysis stage: using a single flow direction algorithm to calculate the flow direction, generating a cumulative flow matrix, and extracting a river network through an adaptive threshold to generate a water system of different densities; and a model constructor division stage: performing series filling of depressions, flow direction, flow, and river network vectorization through the model constructor, and finally realizing the division of natural watersheds. This method only divides natural watersheds and does not solve the connection problem between natural watersheds and administrative boundaries, and cannot realize the accurate matching of township-level administrative units and natural watersheds, resulting in that the division result is difficult to be directly applied to administrative area-watershed management and difficult to support fine watershed management requirements.

[0003] The second method is to manually divide township-level administrative units and hydrological units. The main process includes a basic data preparation stage: superimposing a 1:10,000 scale township administrative map and a 30m resolution hydrological unit map to establish a topological rule library to ensure data consistency; and a manual interpretation stage: manually distinguishing administrative units and hydrological units under the premise of ensuring the integrity of the water system. This method relies on manual superimposition analysis and repeated checking, has low division efficiency and needs multiple manual interventions, cannot realize batch processing, and has low automation degree. SUMMARY

[0004] To solve the above problems, the present application provides a method for automatically dividing a watershed control unit that connects administrative boundaries, comprising the steps of:

[0005] obtaining initial DEM data and administrative division planar vector data of a target area, constructing a buffer zone according to the administrative division planar vector data, and obtaining final DEM data by clipping the initial DEM data according to the buffer zone;

[0006] presetting a cumulative flow threshold and a minimum watershed area of the target area, constructing and optimizing a natural watershed vector plane according to the final DEM data, the cumulative flow threshold, and the minimum watershed area, and obtaining optimized natural watershed vector plane data;

[0007] superimposing and calculating the fitting degree of the administrative division planar vector data and the optimized natural watershed vector plane data to obtain a preliminary watershed control unit;

[0008] According to the minimum watershed area, the preliminary watershed control unit is optimized to obtain a final watershed control unit; and according to the administrative division planar vector data, the final watershed control unit is given a field to obtain a demarcation result of the natural watershed and the administrative boundary.

[0009] Optionally, a buffer zone is constructed according to the administrative division planar vector data, specifically including:

[0010] According to the administrative division planar vector data, township boundary data is obtained, and a township minimum convex polygon is obtained through a fusion tool according to the township boundary data, and a buffer zone is obtained by extending the boundary of the township minimum convex polygon outward.

[0011] Optionally, according to the final DEM data, the cumulative flow threshold and the minimum watershed area, a natural watershed vector plane is constructed and optimized to obtain optimized natural watershed vector plane data, specifically including:

[0012] According to the final DEM data and the cumulative flow threshold, initial natural watershed vector plane data is generated through a hydrological analysis tool chain;

[0013] All natural watersheds of the initial natural watershed vector plane data are obtained, the watershed area of each natural watershed is calculated, and through an elimination tool, natural watersheds with a watershed area less than the minimum watershed area in the initial natural watershed vector plane data are removed to obtain first-stage natural watershed vector plane data;

[0014] A letter sequence is used to give each natural watershed of the first-stage natural watershed vector plane data a unique identifier to obtain optimized natural watershed vector plane data.

[0015] Optionally, the administrative division planar vector data and the optimized natural watershed vector plane data are superimposed and a fitting degree is calculated to obtain a preliminary watershed control unit, specifically including:

[0016] S11: The administrative division planar vector data and the optimized natural watershed vector plane data are superimposed to obtain superimposed vector plane data, and the area of all townships and the area of all villages are calculated according to the superimposed vector plane data;

[0017] S12: The intersection area of all townships and natural watersheds and the intersection area of all villages and natural watersheds are calculated according to the superimposed vector plane data;

[0018] S13: A township i in the superimposed vector plane data is selected;

[0019] S14: A natural watershed x in the superimposed vector plane data is selected;

[0020] S15: A village j in the township i is selected, and the intersection area of the village j and the natural watershed x is calculated, and the area of the village j the percentage of the intersection area of village j and natural watershed x to the area of village j ;

[0021] the percentage of the intersection area of township i and natural watershed x to the area of township i ; the percentage of the sum of the intersection area of all villages in township i and natural watershed x to the area of township i ; the percentage of the sum of the intersection area of all villages in township i and natural watershed x to the area of township i ;

[0022] wherein, i is the number of township, j is the number of village, n is the total number of villages contained in township i, and x is the number of natural watershed;

[0023] S16: repeating step S15 to obtain the fitting degree of all villages in township i and natural watershed x, obtaining a fitting degree threshold, and calculating the fitting degree satisfaction rate of township i and natural watershed x according to the fitting degree of all villages in township i and natural watershed x, the fitting degree threshold, and the total number n of villages contained in township i ;

[0024] S17: calculating the comprehensive fitting degree of township i and natural watershed x according to the fitting degree of township i and natural watershed x and the fitting degree satisfaction rate of township i and natural watershed x ; ;

[0025] S18: repeating steps S14-S17 to obtain the comprehensive fitting degree of township i and all natural watersheds, and taking the natural watershed corresponding to the maximum comprehensive fitting degree as the belonging natural watershed of township i;

[0026] S19: repeating steps S13-S18 to obtain the superimposed vector surface data of the belonging natural watersheds of all townships as the preliminary watershed control unit.

[0027] Optionally, the calculation process of the fitting degree satisfaction rate of township i and natural watershed x specifically includes:

[0028] taking the percentage of the number of villages in township i with a fitting degree greater than the fitting degree threshold to the total number n of villages contained in township i as the fitting degree satisfaction rate of township i and natural watershed x .

[0029] Optionally, the calculation process of the comprehensive fitting degree of township i and natural watershed x specifically includes:

[0030] acquire a first township comprehensive fitting degree coefficient W1 and a second township comprehensive fitting degree coefficient W2, W1+W2=100%;

[0031] multiply the first township comprehensive fitting degree coefficient W1 and the fitting degree of township i and natural watershed x to obtain a first product, multiply the second township comprehensive fitting degree coefficient W2 and the fitting degree satisfaction rate of township i and natural watershed x to obtain a second product, and add the first product and the second product to obtain the comprehensive fitting degree of township i and natural watershed x. .

[0032] Optionally, field assignment is performed on the final watershed control unit according to the administrative division planar vector data, and a delineation result of the natural watershed and the administrative boundary is obtained, specifically including:

[0033] All townships contained in the natural watershed and the area of the natural watershed are acquired according to the final watershed control unit, the township field is acquired according to the administrative division planar vector data, the township field is assigned to all townships contained in the natural watershed, and the natural watershed to which the township field is assigned and the area of the natural watershed are taken as the delineation result of the natural watershed and the administrative boundary.

[0034] The application further provides an automatic delineation device of watershed control units connecting administrative boundaries, which is used to realize the automatic delineation method of watershed control units connecting administrative boundaries.

[0035] A final DEM data acquisition module is configured to acquire initial DEM data and administrative division planar vector data of a target region, construct a buffer zone according to the administrative division planar vector data, and obtain final DEM data by clipping the initial DEM data according to the buffer zone;

[0036] An optimized natural watershed vector plane data acquisition module is configured to preset a cumulative flow threshold and a minimum watershed area of the target region, and construct and optimize a natural watershed vector plane according to the final DEM data, the cumulative flow threshold and the minimum watershed area to obtain optimized natural watershed vector plane data;

[0037] A preliminary watershed control unit acquisition module is configured to superimpose the administrative division planar vector data and the optimized natural watershed vector plane data and calculate a fitting degree to obtain a preliminary watershed control unit;

[0038] A delineation result acquisition module is configured to optimize the preliminary watershed control unit according to the minimum watershed area to obtain a final watershed control unit, and perform field assignment on the final watershed control unit according to the administrative division planar vector data to obtain a delineation result of the natural watershed and the administrative boundary.

[0039] ​​The application further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the administrative boundary-integrated watershed control unit automatic demarcation method when executing the program.

[0040] The application further provides a non-transitory computer readable storage medium, which stores a computer program, wherein the computer program is executable on a processor to implement the administrative boundary-integrated watershed control unit automatic demarcation method.

[0041] The application has the following advantages:

[0042] 1. The final watershed control unit is generated by superimposing the administrative division planar vector data and the optimized natural watershed vector surface data, calculating the fitting degree, judging the township-owned natural watershed, and optimizing the area, so that the township administrative boundary and the natural watershed are seamlessly connected, and all townships contained in each natural watershed and the area of each natural watershed can be obtained, thereby providing a high-precision natural watershed and administrative boundary demarcation result without manual demarcation.

[0043] 2. The township and natural watershed fitting degree satisfaction rate is calculated by the fitting degree, fitting degree threshold value and total number of villages contained in the township, the comprehensive fitting degree of the township and the natural watershed is calculated by the fitting degree of the township and the natural watershed and the township and natural watershed fitting degree satisfaction rate, and finally the township-owned natural watershed is judged by the maximum comprehensive fitting degree; the township-owned natural watershed judgment process considers the influence of the natural watershed on the village, the influence of the natural watershed on the township, and the influence of the village on the township, thereby significantly improving the judgment accuracy of the township-owned natural watershed. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 The embodiment method flowchart of the application is shown in the figure;

[0045] Figure 2 The buffer zone schematic diagram is shown in the figure;

[0046] Figure 3 The superimposed vector surface schematic diagram is shown in the figure;

[0047] Figure 4 The township enclaves and small-area township schematic diagram is shown in the figure;

[0048] Figure 5 The natural watershed and administrative boundary demarcation result schematic diagram is shown in the figure;

[0049] The implementation, functional features and advantages of the application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0050] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present application.

[0051] With reference to Figure 1 The present application provides a method for automatically delineating a watershed control unit across administrative boundaries, comprising the steps of:

[0052] obtaining initial DEM data and administrative division planar vector data of a target area, constructing a buffer zone according to the administrative division planar vector data, and obtaining final DEM data by clipping the initial DEM data according to the buffer zone;

[0053] In some embodiments, the buffer zone is constructed according to the administrative division planar vector data, specifically comprising:

[0054] obtaining township boundary data according to the administrative division planar vector data, obtaining a township minimum convex polygon (the township minimum convex polygon is a polygon of the overall regional boundary composed of all townships) by a fusion tool according to the township boundary data, and expanding the boundary of the township minimum convex polygon outward to obtain a buffer zone.

[0055] In some embodiments, the administrative division planar vector data contains "village" and "township" fields, and the detailed steps of generating a township minimum convex polygon and expanding the buffer zone to a preset range by using a model builder (ArcGIS ModelBuilder) are as follows:

[0056] For example, a mountainous area (containing 122 townships) is taken as the administrative division planar vector data. After loading the administrative division planar vector data, in the ArcToolbox of the model builder, "Data Management Tools > Features > Minimum Bounding Geometry" is selected, the input features are set as the township layer, the output feature class path is selected, and the geometry type is set as "CONVEX_HULL" (convex hull) to generate a minimum convex polygon.

[0057] The "Data Management Tools > Cartographic Generalization > Fuse" tool of the model builder is used, the convex polygon layer generated in the previous step is input, the "Create Multi-Part Features" option is unchecked, and it is ensured that adjacent polygons are merged into a single feature.

[0058] The "Analysis Tools > Neighborhood Analysis > Buffer" of the model builder is opened, the fused convex polygon layer is input, the buffer distance is set as 20 kilometers, the unit is selected as "kilometers", and a buffer zone is generated. The buffer zone is shown as the blue area in Figure 2 .

[0059] The initial DEM data of 30-meter resolution is acquired through the geospatial data cloud, DEM data (30-meter resolution) within the buffer range is cut out in the initial DEM data, DEM data within the buffer range is taken as the final DEM data to eliminate edge errors, and it is noted that the range of the initial DEM data is larger than that of the final DEM data.

[0060] The cumulative flow threshold and the minimum watershed area of the preset target region are determined, and natural watershed vector faces are constructed and optimized according to the final DEM data, the cumulative flow threshold and the minimum watershed area, to obtain optimized natural watershed vector face data.

[0061] In some embodiments, the cumulative flow threshold has no unit and has a value range of about 100000-2000000, and generally, the smaller the value is, the smaller the natural watershed area is, and the size of the target region township area is determined. The minimum watershed area has a unit of square kilometers and is determined according to the minimum value of the generated watershed control unit.

[0062] In some embodiments, the natural watershed vector faces are constructed and optimized according to the final DEM data, the cumulative flow threshold and the minimum watershed area, to obtain optimized natural watershed vector face data, and the construction and optimization specifically include:

[0063] The initial natural watershed vector face data is generated through a hydrological analysis tool chain according to the final DEM data and the cumulative flow threshold;

[0064] In some embodiments, the process of generating the initial natural watershed vector face data through the hydrological analysis tool chain is as follows:

[0065] (1) Depression filling: the final DEM data is processed by using

Spatial Analyst tool > Hydrology > Fill Depressions

[0066] (2) Flow direction analysis: the depression-free DEM is input, the single flow direction algorithm is used to calculate the water flow direction, and the grid is output;

[0067] (3) Flow accumulation calculation: the flow accumulation amount is calculated by using

Hydrology > Flow

[0068] (4) The cumulative flow threshold is set by using the grid calculator, and the selection of the cumulative flow threshold directly affects the river network density (the smaller the value is, the more tributaries there are);

[0069] (5) Catchment generation: the

Capture Depressions

Watershed

[0070] (6) Raster to Polygon: use

Convert > Raster to Polygon

[0071] Get all natural watersheds of the initial natural watershed vector polygon data, calculate the watershed area of each natural watershed, and remove the natural watersheds with an area less than the minimum watershed area from the initial natural watershed vector polygon data using the Eliminate tool to obtain the first-stage natural watershed vector polygon data;

[0072] In some embodiments, remove the patches with an area less than a set value (minimum watershed area, such as 500 km²);

[0073] Assign a unique identifier to each natural watershed of the first-stage natural watershed vector polygon data using the letter sequence to obtain the optimized natural watershed vector polygon data.

[0074] In some embodiments, assign a unique identifier to the "watershed" field of the natural watershed using the letter sequence (A, B, C,..., AA, AB, AC).

[0075] Superimpose and calculate the fitting degree of the administrative district polygon vector data and the optimized natural watershed vector polygon data to obtain the preliminary watershed control unit.

[0076] In some embodiments, superimpose and calculate the fitting degree of the administrative district polygon vector data and the optimized natural watershed vector polygon data to obtain the preliminary watershed control unit, which specifically includes:

[0077] S11: Superimpose the administrative district polygon vector data and the optimized natural watershed vector polygon data to obtain superimposed vector polygon data, and calculate the area of all townships and the area of all villages based on the superimposed vector polygon data;

[0078] In some embodiments, the superimposed vector polygon data is as shown in Figure 3 , where the thick line represents the boundary of the natural watershed, and the thin line represents the boundary of the township.

[0079] S12: Calculate the intersection area of all townships and natural watersheds, and the intersection area of all villages and natural watersheds based on the superimposed vector polygon data;

[0080] S13: Select township i in the superimposed vector polygon data;

[0081] S14: Select natural watershed x in the superimposed vector polygon data;

[0082] S15: Select village j in township i, and calculate the intersection area of village j and natural watershed x, and the area of village j the percentage of the intersection area of village j and natural watershed x to the area of village j ;

[0083] In some embodiments, the fitting degree of village j and natural watershed x is calculated as follows:

[0084]

[0085] the percentage of the intersection area of village j and natural watershed x to the area of village j the percentage of the intersection area of village j and natural watershed x to the area of village j the percentage of the intersection area of village j and natural watershed x to the area of village j the percentage of the intersection area of village j and natural watershed x to the area of village j the percentage of the intersection area of village j and natural watershed x to the area of village j ;

[0086] In some embodiments, the fitting degree of village j and natural watershed x is calculated as follows:

[0087] , or

[0088] wherein, i is the number of township, j is the number of village, n is the total number of villages contained in township i, and x is the number of natural watershed;

[0089] S16: repeating step S15 to obtain the fitting degree of all villages in township i and natural watershed x, obtaining a fitting degree threshold, and calculating the fitting degree satisfaction rate of township i and natural watershed x according to the fitting degree of all villages in township i and natural watershed x, the fitting degree threshold, and the total number n of villages contained in township i ;

[0090] In some embodiments, the fitting degree satisfaction rate of township i and natural watershed x is calculated as follows:

[0091] the percentage of the number of villages in township i with a fitting degree greater than the fitting degree threshold to the total number n of villages contained in township i .

[0092] In some embodiments, the fitting degree satisfaction rate of township i and natural watershed x is calculated as follows:

[0093]

[0094] Under the theoretical condition, an administrative village has at least one and at most x (the total number of natural watersheds) fitting degrees ​​​​, there is only one maximum value, but in general, the natural basin area is much larger than the administrative village area, at this time an administrative village is mostly contained in a natural basin, or is divided by 2 natural basins, divided by 3 and more natural basins, and the fitting degree The fitting degree threshold can be 50%, that is, when 50% of the area of an administrative village is located in a basin, it is determined that the village is an administrative village in the township that meets the fitting degree threshold;

[0095] S17: According to the fitting degree of township i and natural basin x And the fitting degree of township i and natural basin x meets the rate , the comprehensive fitting degree of township i and natural basin x is calculated ;

[0096] In some embodiments, the calculation process of the comprehensive fitting degree of township i and natural basin x Specifically includes:

[0097] Obtain the first township comprehensive fitting degree coefficient W1 and the second township comprehensive fitting degree coefficient W2, W1+W2=100%;

[0098] Multiply the first township comprehensive fitting degree coefficient W1 and the fitting degree of township i and natural basin x Obtain the first product, multiply the second township comprehensive fitting degree coefficient W2 and the fitting degree of township i and natural basin x meets the rate Obtain the second product, and add the first product and the second product to obtain the comprehensive fitting degree of township i and natural basin x .

[0099] In some embodiments, the calculation formula of the comprehensive fitting degree As follows:

[0100] Or

[0101]

[0102] Wherein, the default values of W1 and W2 can be 50% respectively, which can be adjusted according to actual needs, w1>w2, the basin control unit focuses on the integrity of the natural basin to merge the township, w1<w2, the basin control unit focuses on the concentration of administrative villages to merge the township;

[0103] S18: Repeat steps S14-S17 to calculate the comprehensive fitting degree of township i and all natural basins, and take the natural basin corresponding to the maximum comprehensive fitting degree as the belonging natural basin of township i;

[0104] In some embodiments, in the same theoretical condition, a township has at least one and at most x (total number of natural watersheds) fitting degrees , and only one maximum value. Unlike administrative villages, due to the larger area of townships, one township can intersect with three or more natural watersheds, and therefore the determination of the belonging natural watershed of a township cannot rely on the fitting degree alone , but a comprehensive fitting degree is used to determine the belonging natural watershed. That is, the belonging natural watershed of a township is the watershed corresponding to the maximum comprehensive fitting degree value, that is, max( ) watershed.

[0105] S19: Repeat steps S13-S18 to obtain the superimposed vector surface data of the belonging natural watershed of all townships as the preliminary watershed control unit.

[0106] According to the minimum watershed area, the preliminary watershed control unit is optimized to obtain the final watershed control unit; and according to the administrative boundary planar vector data, the final watershed control unit is field-awarded to obtain the delineation result of the natural watershed and the administrative boundary.

[0107] In some embodiments, in the actual management of the administrative boundary, there are many enclaves and small-area townships, and the preliminary watershed control unit obtained by merging townships also has enclaves and small-area townships. A schematic diagram of the enclaves and small-area townships of a township is shown in Figure 4 , in which "Wutai Forest Farm" is the enclave of the red area below, and the areas of "Xianju Township", "Wangdian Township", and "Anfusi Township" are smaller than the minimum watershed area, and "Wutai Forest Farm", "Xianju Township", "Wangdian Township", and "Anfusi Township" need to be removed. Such enclaves and small-area townships need to be processed, and the enclaves and small-area townships smaller than the minimum watershed area in the preliminary watershed control unit are removed to obtain the final watershed control unit, so as to ensure that the final watershed control unit conforms to the natural watershed rule.

[0108] In some embodiments, the final watershed control unit is field-awarded according to the administrative boundary planar vector data to obtain the delineation result of the natural watershed and the administrative boundary, which specifically includes:

[0109] According to the final watershed control unit, all townships contained in the natural watershed and the area of the natural watershed are obtained, the township field is obtained according to the administrative boundary planar vector data, the township field is awarded to all townships contained in the natural watershed, and the natural watershed and the area of the natural watershed after the township field is awarded are taken as the delineation result of the natural watershed and the administrative boundary.

[0110] In some embodiments, the delineation result of the natural watershed and the administrative boundary is as shown in Figure 5As shown, 122 townships are divided into 16 natural watersheds, and the natural watersheds and the area of the natural watersheds after the township field is output as a table for display.

[0111] The application further provides a watershed control unit automatic division device for connecting administrative boundaries, which is used for implementing the watershed control unit automatic division method for connecting administrative boundaries, and the device comprises:

[0112] An ultimate DEM data acquisition module is configured to acquire initial DEM data and administrative division planar vector data of a target region, construct a buffer zone according to the administrative division planar vector data, and obtain ultimate DEM data by clipping the initial DEM data according to the buffer zone;

[0113] An optimized natural watershed vector plane data acquisition module is configured to preset a cumulative flow threshold and a minimum watershed area of the target region, and construct and optimize a natural watershed vector plane according to the ultimate DEM data, the cumulative flow threshold and the minimum watershed area, so as to obtain optimized natural watershed vector plane data;

[0114] A preliminary watershed control unit acquisition module is configured to superimpose the administrative division planar vector data and the optimized natural watershed vector plane data and calculate a fitting degree, so as to obtain a preliminary watershed control unit;

[0115] A division result acquisition module is configured to optimize the preliminary watershed control unit according to the minimum watershed area, so as to obtain a final watershed control unit; and perform field assignment on the final watershed control unit according to the administrative division planar vector data, so as to obtain a division result of the natural watershed and the administrative boundary.

[0116] The application embodiment provides an electronic device, comprising a processor and a memory; the memory has a computer program stored therein, wherein the computer program, when executed by the processor, implements the watershed control unit automatic division method for connecting administrative boundaries according to any one of the above-mentioned schemes.

[0117] Specifically, the processor may, for example, include a general-purpose microprocessor, an instruction set processor, and / or a related chipset, and / or a special-purpose microprocessor (such as an application-specific integrated circuit (ASIC)), etc. The processor may also include an on-board memory for cache use. The processor may be a single processing unit or a plurality of processing units for performing different actions of the method process according to the application embodiment.

[0118] Memory, for example, can be any media capable of storing, containing, communicating, propagating, or transporting instructions. For example, memory can include, without limitation, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, devices, or propagation mediums. Specific examples of memory include magnetic storage devices such as hard disks or hard disk drives (HDDs); optical storage devices such as compact disc (CD-ROM); and / or wired / wireless communication links.

[0119] The application also provides a computer readable medium having stored thereon a computer program which, when executed by a processor, implements the method of automatically delineating a catchment administrative boundary control unit according to any of the above-mentioned solutions. The computer readable medium can be included in the device / apparatus / system described in the above-mentioned embodiments; or can exist separately and not be assembled into the device / apparatus / system. The computer readable medium carries one or more programs which, when executed, implement the method according to the embodiments of the application.

[0120] According to the embodiments of the application, the computer readable medium can be a computer readable signal medium or a computer readable storage medium or any combination of the two. The computer readable storage medium may, for example, be, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the above. More specific examples of the computer readable storage medium can include, but are not limited to, an electrical connection having one or more wires, a portable computer diskette, 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 disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this application, the computer readable storage medium can be any tangible medium that contains or stores a program used by or in connection with an instruction execution system, apparatus, or device. In this application, the computer readable signal medium can include a data signal carried by a baseband or as part of a carrier wave. Such a propagated data signal can take any of a variety of forms, including but not limited to electro-magnetic, optical, or any suitable combination thereof. The computer readable signal medium can also be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport programs for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer readable medium can be transmitted by any suitable medium, including but not limited to wireless, wired, optical, electromagnetic, or any suitable combination thereof. The computer readable medium can be included in the device / apparatus / system described in the above-mentioned embodiments; or can exist separately and not be assembled into the device / apparatus / system.

[0121] It will be appreciated by those skilled in the art that features of the various embodiments and / or claims of the present application can be combined and / or interchanged, even though such combinations and / or interchanges are not expressly disclosed in the present application. In particular, the features of the various embodiments and / or claims of the present application can be combined and / or interchanged, even though such combinations and / or interchanges are not expressly disclosed in the present application. All of these combinations and / or interchanges are within the scope of the present application. Accordingly, the scope of the present application should not be limited to the above-described embodiments, but should be determined by the appended claims and their equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the present application.

Claims

1. A method for automatically delineating watershed control units that connect administrative boundaries, characterized in that, Including the following steps: Acquire the initial DEM data and administrative division isometric vector data of the target area, construct a buffer based on the administrative division isometric vector data, and crop the initial DEM data based on the buffer to obtain the final DEM data; The cumulative flow threshold and minimum watershed area of ​​the target area are preset. Based on the final DEM data, the cumulative flow threshold and minimum watershed area, the natural watershed vector surface is constructed and optimized to obtain optimized natural watershed vector surface data. By overlaying and calculating the fit of administrative division surface vector data and optimized natural watershed vector surface data, a preliminary watershed control unit is obtained; The preliminary watershed control unit is optimized based on the minimum watershed area to obtain the final watershed control unit; the final watershed control unit is assigned fields based on the administrative division isometric vector data to obtain the delineation results of natural watersheds and administrative boundaries; By overlaying and calculating the goodness of fit of administrative division areal vector data and optimized natural watershed vector areal data, a preliminary watershed control unit is obtained, which specifically includes: S11: Overlay the administrative division area vector data and the optimized natural watershed vector area data to obtain overlaid vector area data. Calculate the area of ​​all townships and the area of ​​all villages based on the overlaid vector area data. S12: Calculate the intersection area between all townships and natural watersheds, and the intersection area between all villages and natural watersheds based on the superimposed vector surface data; S13: Select township i from the overlay vector surface data; S14: Select the natural watershed x from the overlay vector surface data; S15: Select village j in township i, and calculate the intersection area between village j and natural watershed x. Area of ​​village j The percentage is used as the goodness of fit between village j and natural watershed x. ; The intersection area of ​​township i and natural watershed x Area of ​​township i The percentage, or the sum of the areas of intersection between all villages within township i and the natural watershed x. Area of ​​township i The percentage is used as the goodness of fit between township i and natural watershed x. ; in, , i is the township number, j is the village number, n is the total number of villages contained in township i, and x is the natural watershed number; S16: Repeat step S15 to calculate the goodness of fit between all villages in township i and natural watershed x, obtain the goodness of fit threshold, and calculate the goodness of fit satisfaction rate between township i and natural watershed x based on the goodness of fit between all villages in township i and natural watershed x, the goodness of fit threshold, and the total number of villages n in township i. ; S17: Based on the goodness of fit between township i and natural watershed x The goodness-of-fit rate between township i and natural watershed x The overall fit between township i and natural watershed x is calculated. ; S18: Repeat steps S14-S17 to calculate the comprehensive fit between township i and all natural watersheds, and take the natural watershed corresponding to the maximum comprehensive fit as the natural watershed to which township i belongs. S19: Repeat steps S13-S18 to obtain the superimposed vector surface data of the natural watersheds of all townships as the preliminary watershed control unit.

2. The method for automatically delineating watershed control units connecting administrative boundaries according to claim 1, characterized in that, A buffer is constructed based on the administrative division areal vector data, specifically including: Township boundary data is obtained from the administrative division area vector data. The minimum convex polygon of the township is obtained from the township boundary data through a fusion tool. The boundary of the minimum convex polygon of the township is extended outward to obtain a buffer zone.

3. The method for automatically delineating watershed control units connecting administrative boundaries according to claim 1, characterized in that, Based on the final DEM data, cumulative flow threshold, and minimum watershed area, the natural watershed vector surface is constructed and optimized to obtain optimized natural watershed vector surface data, specifically including: Based on the final DEM data and cumulative flow thresholds, initial natural watershed vector surface data are generated using a hydrological analysis toolchain. All natural watersheds in the initial natural watershed vector surface data are obtained, the watershed area of ​​each natural watershed is calculated, and natural watersheds with watershed areas smaller than the minimum watershed area in the initial natural watershed vector surface data are removed by elimination tools to obtain the first stage natural watershed vector surface data. Each natural watershed in the first-stage natural watershed vector surface data is assigned a unique identifier using a letter sequence to obtain optimized natural watershed vector surface data.

4. The method for automatically delineating watershed control units connecting administrative boundaries according to claim 1, characterized in that, The goodness-of-fit rate between township i and natural watershed x The calculation process specifically includes: The percentage of villages within township i whose goodness of fit with natural watershed x exceeds the goodness-of-fit threshold, compared to the total number of villages n within township i, is taken as the goodness-of-fit satisfaction rate between township i and natural watershed x. .

5. The method for automatically delineating watershed control units connecting administrative boundaries according to claim 1, characterized in that, The overall fit between township i and natural watershed x The calculation process specifically includes: Obtain the comprehensive fit coefficient W1 of the first township and the comprehensive fit coefficient W2 of the second township, where W1 + W2 = 100%; The comprehensive fit coefficient W1 of the first township and the fit between township i and the natural watershed x are calculated. Multiply them to obtain the first product, and then combine the comprehensive fit coefficient W2 of the second township with the fit rate of township i to the natural watershed x. Multiply the first and second products to obtain the second product. Add the first and second products to obtain the overall fit between township i and natural watershed x. .

6. The method for automatically delineating watershed control units connecting administrative boundaries according to claim 1, characterized in that, Based on the administrative division isometric vector data, fields are assigned to the final watershed control unit to obtain the delineation results of natural watersheds and administrative boundaries, specifically including: The final watershed control unit obtains all townships included in the natural watershed and the area of ​​the natural watershed. The township field is obtained from the administrative division area vector data. The township field is assigned to all townships included in the natural watershed. The natural watershed and the area of ​​the natural watershed after assigning the township field are used as the delineation results of the natural watershed and the administrative boundary.

7. An automated delineation device for watershed control units connecting administrative boundaries, used to implement the automated delineation method for watershed control units connecting administrative boundaries as described in any one of claims 1 to 6, characterized in that, The device includes: The final DEM data acquisition module is used to acquire the initial DEM data and administrative division isometric vector data of the target area, construct a buffer based on the administrative division isometric vector data, and crop the initial DEM data based on the buffer to obtain the final DEM data. The module for acquiring optimized natural watershed vector surface data is used to preset the cumulative flow threshold and minimum watershed area of ​​the target area. Based on the final DEM data, the cumulative flow threshold and the minimum watershed area, the module constructs and optimizes the natural watershed vector surface to obtain optimized natural watershed vector surface data. The preliminary watershed control unit acquisition module is used to overlay and calculate the fitting degree of administrative division surface vector data and optimized natural watershed vector surface data to obtain the preliminary watershed control unit. The delineation result acquisition module is used to optimize the preliminary watershed control unit based on the minimum watershed area to obtain the final watershed control unit; and to assign fields to the final watershed control unit based on the administrative division isometric vector data to obtain the delineation results of natural watersheds and administrative boundaries.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the automated delineation method for watershed control units that connect administrative boundaries as described in any one of claims 1 to 6.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the automated delineation method for watershed control units that connect administrative boundaries as described in any one of claims 1 to 6.

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