Efficient visualization analysis method for land use change flow

Abstract

The application discloses a kind of efficient visual analysis methods of land use change flow, it is related to geographic information system field, the method is by to the spatial data achievement of two tuning and three tuning is cut, spatial overlay analysis and intersection takes reverse analysis, and based on accumulation column chart form, efficiently visual display is carried out to land use change flow.In the application, by simplifying flow calculation storage mode and intuitive data visualization display means, while solving the existing flow calculation result complex, visual display lacks, data screening lacks and other problems, the efficient visual analysis of land use change flow is realized.

Description

Technical Field

[0001] This invention belongs to the field of geographic information systems, and specifically relates to an efficient visualization analysis method for land use change flows. Background Technology

[0002] During the implementation of land survey projects, it is necessary to analyze and improve historical survey results to identify detailed changes in land use types within the region. Specifically, based on the data from the Third National Land Survey, and combined with relevant data from the Second National Land Survey and annual land change surveys, spatial data overlay analysis is performed. Various analytical methods, including comparative and comprehensive analysis, are employed to conduct flow analysis on key land types such as cultivated land, construction land, other grasslands, and wetlands, providing important reference for natural resource management and leadership decision-making.

[0003] Existing third-level survey database construction software can perform traffic analysis, but it requires the establishment of a complete database for the platform software, has high requirements for data format, is cumbersome, and the calculation results are mostly presented in tabular form, or even in "traffic matrices" with fifty or sixty rows and columns, which has poor intuitive display effect. Summary of the Invention

[0004] The purpose of this invention is to solve the problems existing in the prior art and provide an efficient and visual analysis method for land use change flows. This invention solves the problems of efficient calculation of spatial change flows in land use surveys and intuitive and convenient data display, and has great application value in future land management, land planning, and construction land approval.

[0005] The specific technical solution adopted in this invention is as follows:

[0006] An efficient visualization analysis method for land use change flows, comprising the following steps:

[0007] S1. Perform overlay analysis on land cover patches, linear features, scattered features from the second land survey, and land cover patches from the third land survey within a given range:

[0008] S101: Based on the given analysis range, the land use patches of the second land survey are cropped to obtain the cropped land use patches of the second land survey;

[0009] S102: Traverse the clipped second-order land use patches, and then perform intersection processing with the given third-order land use patches to obtain the intersecting areal features;

[0010] S103: The planar features obtained after the intersection of S102 are buffered to obtain a slightly enlarged polygon;

[0011] As a preferred option, the buffer distance of S103 is selected as 0.01 to 0.05 m, in order to eliminate the influence of topological tolerance and improve the accuracy of spatial calculation of linear features.

[0012] S104: Find all scattered features that intersect with the polygons obtained in step S103 above, and traverse them. Perform spatial analysis on each scattered feature and the buffered areal features to analyze whether the scattered features are located within the buffered polygons.

[0013] S105: For scattered features located within a polygon, record the land use code and area of ​​the scattered feature;

[0014] S106: After the traversal is completed, summarize the total area of ​​the scattered features within the polygon and use it as one of the deducted areas of the flow patch;

[0015] S107: Find all linear features that intersect with the polygons obtained in step S103 above, and traverse them. Perform intersection processing on each di-tone linear feature and the buffered area features to obtain the intersecting line features.

[0016] S108: For the line features obtained in S107 above, record their length, width, and deduction ratio, and calculate the area of ​​the line features; calculate according to the following formula:

[0017] Area of ​​linear features = Length × Width × Deduction factor;

[0018] S109: For intersecting line features, record their land use code and area;

[0019] S120: After traversal, summarize the total area of ​​linear features within the polygon, and use it as one of the deducted areas for the flow patch;

[0020] S121: After the overlay processing of scattered and linear features is completed, the deducted area of ​​the flow patch is summarized and calculated according to the following formula:

[0021] Area deducted = Area of ​​linear features + Area of ​​scattered features + Area of ​​field ridges;

[0022] Field ridge area = (area of ​​graphic features - area of ​​linear features - area of ​​scattered features) × field ridge coefficient;

[0023] S122: Construct the flow calculation table for this flow patch; the main information recorded in this table includes: land category code, land category name, major category, first category, area deducted in the second land survey, land category code, land category name, major category, area of ​​the patch, etc.

[0024] S123: Traverse the next land parcel in the second land survey within the analysis range until all land parcels in the second land survey have been processed;

[0025] S2. Perform spatial inversion analysis on the second land survey land parcels, second land survey linear features, second land survey scattered features and third land survey land parcels within a given range;

[0026] S201: After giving the analysis range and the land use map pieces from the third land survey, trim the land use map pieces from the third land survey;

[0027] S202: Merge all cropped third-survey land cover patches, and then determine whether the given scattered second-survey land features are within the merged third-survey land cover patches;

[0028] S203; When scattered land features are not within the merged land use map after the third land survey, it indicates that the scattered land features are net outflow areas and should be included in the outflow area.

[0029] S204: Given linear land features from the second land survey, perform a cropping operation with the merged third land survey land parcels;

[0030] S205: When the cropped graphic is empty, it means that the linear feature is outside the merged polygon and is included in the outflow area according to the linear feature area calculation formula.

[0031] S206: Traverse the cropped third-level land use map features. Given a second-level land use map feature, perform an intersection and inversion operation on the two maps.

[0032] S207: If the result of the intersection inversion is not empty, then determine whether the result is a third-level land survey patch based on the fields of the feature class;

[0033] S208: Determine whether the inverted intersection result is a third-level land survey patch based on the inverted fields. If it is a third-level land survey patch, include it in the net inflow area.

[0034] S209: Based on the judgment result of step S207 above, if it is not a land parcel from the third national land survey, then the net outflow area shall be included.

[0035] S210: Construct a custom flow calculation table, and then perform the next iteration of the three-level survey patch;

[0036] S3: Merge all calculated flow calculation tables;

[0037] S4: Use stacked bar charts to display the results of flow analysis, including setting up chart linkage based on filter criteria.

[0038] The beneficial effects of this invention are as follows: 1) The traffic analysis of this invention is based on a given range, that is, the analysis range is clearly defined, so that the analysis work is no longer limited to the overall size of the basic data results, which is conducive to daily traffic analysis for a small range; 2) This invention adopts a custom traffic calculation table format, which simplifies the practice of retaining all fields of the original data results in the traditional method, making the processing flow simpler and more intuitive; 3) This invention uses a stacked bar chart for traffic analysis and supports the display after filtering, avoiding the generation of a large amount of redundant information, and is more adaptable to future thematic analysis work for a certain region or a certain type.

[0039] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the overall process of the present invention.

[0041] Figure 2 This is a flowchart illustrating step S1.

[0042] Figure 3 This is a flowchart illustrating step S2.

[0043] Figure 4 This is a visualization of the traffic analysis results in the example. Detailed Implementation

[0044] See Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown.

[0045] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0046] like Figure 1 As shown, this example provides an efficient visualization analysis method for land use change flows. This method involves cropping, overlaying, intersection negation, constructing a custom calculation table, and displaying the calculation results in a filterable and visual manner, including the following steps:

[0047] Step S1 involves overlaying and analyzing the second land survey land parcels, linear features, scattered features, and third land survey land parcels within a given range, and storing the calculation results using a custom flow calculation table. The specific steps are described below.

[0048] Step S2 involves performing spatial inversion analysis on the second land survey land parcels, second land survey linear features, second land survey scattered features, and third land survey land parcels within a given range, and storing the calculation results using a custom flow calculation table. The specific steps are described below.

[0049] Step S3: Combine the results calculated in S1 and S2 above;

[0050] Step S4: Use a stacked bar chart to display the flow analysis results;

[0051] like Figure 2 As shown, the spatial overlay processing procedure in step S1 specifically includes the following steps:

[0052] S101: Based on the given analysis range, which is a polygon stored as a planar feature class, the second-order land cover patches are clipped to obtain multiple clipped second-order land cover patches.

[0053] S102: Traverse each of the second land survey patch after clipping, find the third land survey patch that intersects with it through spatial search, and perform intersection processing to obtain the intersecting areal feature. The areal feature is the intersection of the two patches and has fields and values ​​of both the second and third land survey data.

[0054] S103: The planar features obtained after the intersection of S102 are buffered to obtain a slightly enlarged polygon;

[0055] S104: By judging spatial relationships, find all scattered ground features that intersect with the polygons obtained in step S103 above;

[0056] S105: For scattered land features located within a polygon, construct a record in a custom flow calculation table, recording the land type code and area of ​​the scattered land feature and the land type code and area of ​​the third land survey patch that intersects with it, and simultaneously find the primary category and major category of the land type code of the second and third land surveys.

[0057] S106: After the traversal is completed, summarize the total area of ​​the scattered features within the polygon and use it as one of the deducted areas of the flow patch;

[0058] S107: Find all linear features that intersect with the polygons obtained in step S103 above, and traverse them. Perform intersection processing on each di-tone linear feature and the buffered area features to obtain the intersecting line features.

[0059] S108: For the linear features obtained in S107 above, record their land use code, length, width, and deduction ratio, and calculate the area of ​​the linear features; calculate according to the following formula:

[0060] Area of ​​linear features = Length × Width × Deduction factor;

[0061] S109: For intersecting line features, record their land use codes and areas, construct a custom flow calculation table record, record the land use codes and areas of the scattered land features and the land use codes and areas of the intersecting third land survey patches, and simultaneously find the primary category and major category of the land use codes of the second and third land surveys.

[0062] S120: After traversal, summarize the total area of ​​linear features within the polygon, and use it as one of the deducted areas for the flow patch;

[0063] S121: After the overlay processing of scattered and linear features is completed, the deducted area of ​​the flow patch is summarized and calculated according to the following formula:

[0064] Area deducted = Area of ​​linear features + Area of ​​scattered features + Area of ​​field ridges;

[0065] Field ridge area = (area of ​​graphic features - area of ​​linear features - area of ​​scattered features) × field ridge coefficient;

[0066] S122: Construct the flow calculation table for this flow patch. The main information recorded in the table includes: land category code, land category name, major category, first-level category, area deducted in the second land survey, land category code, land category name, major category, and area of ​​the patch.

[0067] S123: Perform a traversal of the next land parcel in the analysis range until all land parcels in the second land survey have been processed.

[0068] like Figure 3 As shown, the spatial data intersection inversion process in step S2 specifically includes the following steps:

[0069] S201: Given an analysis range, which is determined by a polygon, the land use patches of the third survey are then clipped according to the polygon to obtain multiple clipped land use patches of the third survey.

[0070] S202: Merge all cropped third-level land cover patches to form a single polygon, and then determine whether the given second-level scattered land features are within the merged polygon;

[0071] S203: When a scattered feature is not within the merged polygon, it means that the feature is only within the scope of the second land survey data and not within the scope of the third land survey. Therefore, it is a net outflow area and is included in the outflow area. Construct a flow calculation table for the flow patch. This table records the main outflow land type codes and outflow area information from the second land survey.

[0072] S204: Given linear land features from the second land survey, perform a cropping operation with the merged third land survey land parcels;

[0073] S205: When the cropped graphic is empty, it means that the linear feature is outside the merged polygon. According to the linear feature area calculation formula, the outflow area is included, and a flow calculation table for the flow patch is constructed. The table records the main second-level survey outflow land type code, outflow area and other information.

[0074] S206: Traverse the trimmed third-level land use map patches, and simultaneously traverse all second-level land use map patches, performing an intersection and inversion operation on the two maps;

[0075] S207: If the result of the intersection inversion is not empty, it means that there is a difference between the two graphics. Then, determine whether the result is a third-level land survey patch based on the field of the feature class.

[0076] In this example, the length of the land cover code is used to determine whether it is a land cover patch from the Third National Land Survey. When the land cover code length is 4, it indicates that it is a land cover patch from the Third National Land Survey.

[0077] S208: Determine whether the inverted intersection result is a third-level land survey patch based on the inverted fields. If it is a third-level land survey patch, include it in the net inflow area.

[0078] S209: Based on the judgment result of step S207 above, if it is not a land parcel from the third national land survey, then the net outflow area shall be included.

[0079] S210: Construct a custom flow calculation table, and then perform the next iteration of the three-level survey patch;

[0080] In step S3 above, the calculation results of various types of flow are merged:

[0081] The flow calculation results mainly include the following information:

[0082] Source element ID, source element land use code, source element major category, source element first-level category, source element deducted area, target element ID, target element land use code, target element major category, target element first-level category, target element deducted area, and element type.

[0083] like Figure 4 As shown, the flow analysis using stacked bar charts in step S4 above includes statistical charts. Due to the large amount of data, setting statistical charts allows for viewing different filtered results, facilitating understanding and analysis. By filtering and querying the flow calculation table, any column can be filtered, allowing for analysis and intuitive display of results for specific land use types or categories of interest. Moving the mouse over the stacked bar chart of interest displays the inflow and outflow information and detailed area for that land use type. By setting the area unit, the stacked bar chart can be redrawn according to the selected area unit.

[0084] The above descriptions are merely some specific embodiments of the present invention. Commonly known details or common knowledge in the solutions are not described in detail here (including but not limited to abbreviations and acronyms). It should be noted that the above embodiments do not limit the present invention in any way. For those skilled in the art, any technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of the present invention. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A highly efficient visualization analysis method for land use change flows, characterized in that, The visualization analysis method includes the following steps: Step S1 involves overlaying and analyzing the second land survey land parcels, linear features, scattered features, and third land survey land parcels within a given range, and storing the calculation results using a custom flow calculation table. Step S2: Perform spatial inversion analysis on the second land survey land parcels, second land survey linear features, second land survey scattered features and third land survey land parcels within a given range, and store the calculation results using a custom flow calculation table; Step S3: Combine the results calculated in S1 and S2 above; Step S4: Present the results of the traffic analysis; Step S1 specifically includes the following steps: S101: Based on the given analysis range, the land use patches of the second land survey are cropped to obtain the cropped land use patches of the second land survey; S102: Traverse the clipped second-order land use patches, and then perform intersection processing with the given third-order land use patches to obtain the intersecting areal features; S103: The planar features obtained after the intersection of S102 are buffered to obtain a slightly enlarged polygon; S104: Find all scattered features that intersect with the polygons obtained in step S103 above, and traverse them. Perform spatial analysis on each scattered feature and the buffered areal features to analyze whether the scattered features are located within the buffered polygons. S105: For scattered features located within a polygon, record the land use code and area of ​​the scattered feature; S106: After the traversal is completed, summarize the total area of ​​the scattered features within the polygon and use it as one of the areas to be deducted from the flow patch. S107: Find all linear features that intersect with the polygons obtained in step S103 above, and traverse them. Perform intersection processing on each di-tone linear feature and the buffered area features to obtain the intersecting line features. S108: For the line features obtained in S107 above, record their length, width, and deduction ratio, and calculate the area of ​​the line features; calculate according to the following formula: Area of ​​line features = Length × Width × Deduction coefficient; S109: For intersecting line features, record their land use code and area; S120: After traversal, summarize the total area of ​​linear features within the polygon and use it as one of the deducted areas of the flow patch; S121: After the overlay processing of scattered features and linear features is completed, the deducted area of ​​the summary flow plots is calculated according to the following formula: Deducted area = Area of ​​linear features + Area of ​​scattered features + Area of ​​field ridges; Field ridge area = (area of ​​flow plots - area of ​​linear features - area of ​​scattered features) × field ridge coefficient; S122: Construct a flow calculation table for flow patches; S123: Traverse the next land parcel in the second land survey within the analysis range until all land parcels in the second land survey have been processed; Step S2 specifically includes the following steps: S201: After giving the analysis range and the land use map pieces from the third land survey, trim the land use map pieces from the third land survey; S202: Merge all cropped third-survey land cover patches, and then determine whether the given scattered second-survey land features are within the merged third-survey land cover patches; S203; When scattered land features are not within the merged land use map after the third land survey, it indicates that the scattered land features are net outflow areas and should be included in the outflow area. S204: Given linear land features from the second land survey, perform a cropping operation with the merged third land survey land parcels; S205: When the cropped graphic is empty, it means that the linear feature is outside the merged polygon and is included in the outflow area according to the linear feature area calculation formula. S206: Traverse the trimmed third-level land use map patches. Given a second-level land use map patch, perform an intersection and inversion operation on the two maps. S207: If the result of the intersection inversion is not empty, then determine whether the result is a third-level land survey patch based on the fields of the feature class; S208: Determine whether the inverted intersection result is a third-level land survey patch based on the inverted fields. If it is a third-level land survey patch, include it in the net inflow area. S209: Based on the judgment result of step S207 above, if it is not a land parcel from the third national land survey, then the net outflow area shall be included. S210: Construct a custom flow calculation table, and then perform the next iteration of the three-level survey patch.

2. The efficient visualization analysis method for land use change flow according to claim 1, characterized in that, Specifically, step S4 involves using a stacked bar chart to display the results of the flow analysis.

3. The efficient visualization analysis method for land use change flow according to claim 1, characterized in that, The buffer distance of S103 is selected to be 0.01 to 0.05 m.

4. The efficient visualization analysis method for land use change flow according to claim 1, characterized in that, The information recorded in the S122 flow calculation table includes: land category code, land category name, major category, primary category, area deducted in the second land survey, land category code, land category name, major category, and area of ​​the map patch.

5. The efficient visualization analysis method for land use change flow according to claim 1, characterized in that, Specifically, S207 involves determining whether a land parcel is a third land survey patch by judging the length of the land parcel code. When the land parcel code length is 4, it indicates that the land parcel is a third land survey patch.

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