Ecological source place identification method and system based on ecological system service and ecological sensitivity evaluation

Abstract

The invention relates to an ecological source identification method and system based on ecological system service and ecological sensitivity evaluation. The method comprises the following steps: acquiring original data for evaluation and analysis of a research area in a preset time range, and performing ecological system service function importance evaluation and analysis and ecological sensitivity evaluation and analysis to obtain an ecological system service function importance level and an ecological sensitivity level; extracting plaques with high ecological system service function importance level, high ecological sensitivity level and area not smaller than a set area threshold as preliminary ecological plaques, selecting an ecological source from the preliminary ecological plaques according to a landscape connectivity analysis result, and determining the stability level of the ecological source; the system comprises a preprocessing module, a calculation module, an extraction module, a screening module and a determination module. The method is simple and efficient in calculation process, has high flexibility, and can assist a decision maker to quickly and accurately lock a key ecological region in dynamic environment transition.

Description

Technical Field

[0001] The present invention relates to an ecological source identification method and system, in particular to an ecological source identification method based on ecosystem service function importance evaluation and ecological sensitivity evaluation and a computer system for implementing ecological source identification using the method, belonging to the technical field of ecological environment protection and regional space planning. Background Art

[0002] The ecological source is the core area of ​​the ecological protection area and the area with the most stable internal structure and function of the ecosystem, which plays a decisive role in the health and safety of the land. On the basis of accurate identification of the ecological source, by scientifically defining the layout of ecological corridors and key ecological nodes, the efficiency of material circulation, energy flow and information transmission within the ecosystem can be significantly enhanced, ensuring the maximization of the ecosystem function and service potential. Therefore, the identification of the ecological source plays a vital role in optimizing the ecological space structure layout, building an ecological security pattern and guiding the rational formulation of ecological space governance policies.

[0003] At present, there are three main methods for identifying ecological sources: First, directly select large-scale habitat patches as source areas, such as nature reserves, scenic spots, large-scale forestry, farmland, etc. Although this method is convenient, it is highly subjective and does not consider the ecological degradation and landscape fragmentation in the region; second, use an assessment system to identify the importance of patches, usually from the perspectives of ecological service function value, landscape patch quality, ecological importance and ecological sensitivity, and quantitatively measure and compare the importance of patches in habitat quality assessment. This method focuses on the properties of ecological patches themselves and ignores the importance of ecological patch structure and its importance in maintaining the overall regional landscape connectivity; third, consider the scale of landscape components and use the granularity inversion method to select ecological sources from the perspective of landscape connectivity. These methods have their own characteristics and are adapted to their respective needs, but they also have their own limitations.

[0004] On the other hand, ecosystem service functions and ecological sensitivity are two important indicators in the field of ecological research, which are of great significance to the evaluation of ecological importance and the zoning of dominant ecological functions. The evaluation of the importance of ecosystem service functions takes into account the contribution of ecosystems to human well-being, while the evaluation of ecological vulnerability focuses on the stability and anti-interference ability of ecosystems, and evaluates the resistance of the natural environment to external interference and pressure. Therefore, it should become an important factor in the construction of ecological security pattern. Summary of the invention

[0005] The purpose of the present invention is to provide an ecological source identification method and system based on ecosystem service and ecological sensitivity assessment.

[0006] The technical solution of the present invention is: an ecological source identification method based on ecosystem service and ecological sensitivity evaluation, comprising:

[0007] Obtain the original data for ecosystem service function importance evaluation and ecological sensitivity evaluation in the study area within the preset time range, pre-process the original data (or data cleaning, for example, eliminating erroneous data, filling in missing data, standardizing / unifying data formats, etc.), and form basic data for service function importance evaluation and ecological sensitivity evaluation;

[0008] Based on the basic data, the importance evaluation and analysis of ecosystem service functions (including the required calculations) are carried out to obtain the data of each evaluation index used for the importance evaluation of ecosystem service functions, and the corresponding comprehensive evaluation data are obtained by weighted summation based on the data of each evaluation index and the weight of each evaluation index. The comprehensive evaluation data are graded to obtain the importance level (or level value) of the ecosystem service functions;

[0009] Based on the basic data, ecological sensitivity evaluation and analysis are carried out to obtain the data of each evaluation factor used for ecological sensitivity evaluation and analysis, and each evaluation factor is graded according to the data of each evaluation factor. The value of each evaluation factor is obtained according to the grading of each evaluation factor, and the weighted sum is performed according to the value of each evaluation factor and the weight of each evaluation factor to obtain the corresponding comprehensive evaluation data, and the comprehensive evaluation data is graded to obtain the ecological sensitivity level;

[0010] Extract patches with high importance of ecosystem service functions, high ecological sensitivity and an area not less than (or greater than) the set area threshold as stable ecological patches (or preliminary ecological sources);

[0011] Landscape connectivity analysis was conducted on stable ecological patches, and stable ecological patches with patch importance index greater than the set value were selected as ecological sources (identified / confirmed ecological sources, or stable ecological sources).

[0012] Preferably, when conducting landscape connectivity analysis on stable ecological patches, a connectivity distance threshold is set, and patches beyond the connectivity distance threshold are not considered.

[0013] Furthermore, for the selected ecological source areas, the stability level of the ecological source areas is determined based on the results of landscape connectivity analysis.

[0014] Preferably, the evaluation indicators used for evaluating the importance of ecosystem service functions are water conservation capacity, soil and water conservation service capacity index and biodiversity maintenance service capacity index.

[0015] Furthermore, the weights of water conservation capacity, soil and water conservation service capacity index and biodiversity maintenance service capacity index may be 0.4, 0.3 and 0.3 respectively.

[0016] Preferably, the evaluation factors used for ecological sensitivity assessment analysis are elevation, slope, distance to water source buffer zone, vegetation coverage, average annual precipitation and land use type.

[0017] Preferably, the weight calculation of each evaluation factor is implemented based on the hierarchical analysis method, and the weight of each evaluation factor is determined according to the expert consultation results.

[0018] Furthermore, the weights of elevation, slope, water source buffer distance, vegetation coverage, average annual precipitation, and land use type can be 0.1837, 0.1016, 0.1894, 0.2107, 0.0869, and 0.2277, respectively.

[0019] Preferably, the ecosystem service function importance evaluation analysis and ecological sensitivity evaluation analysis are implemented with a uniform pixel size.

[0020] An ecological source identification system based on ecosystem service function importance evaluation and ecological sensitivity evaluation adopts any ecological source identification method based on ecosystem service function importance evaluation and ecological sensitivity evaluation disclosed in the present invention to implement ecological source identification.

[0021] Further, the system comprises:

[0022] Preprocessing module: used to obtain the original data for ecosystem service function importance evaluation and ecological sensitivity evaluation in the study area within a preset time range, preprocess the original data (or data cleaning, for example, eliminating erroneous data, filling in missing data, standardizing / unifying data format, etc.), and form basic data for ecosystem service function importance evaluation and ecological sensitivity evaluation;

[0023] Calculation module: used to conduct ecosystem service function importance evaluation analysis (including required operations) based on basic data, obtain various evaluation index data used for ecosystem service function importance evaluation, perform weighted summation based on various evaluation index data and the weight of each evaluation index, obtain corresponding comprehensive evaluation data, perform grading based on the comprehensive evaluation data, and obtain the service function importance level; conduct ecological sensitivity evaluation analysis based on basic data, obtain various evaluation factor data used for ecological sensitivity evaluation analysis, perform grading based on various evaluation factor data, obtain various evaluation factor values ​​based on the grading of various evaluation factors, perform weighted summation based on various evaluation factor values ​​and the weight of each evaluation factor, obtain corresponding comprehensive evaluation data, perform grading based on the comprehensive evaluation data, and obtain ecological sensitivity level;

[0024] Extraction module: used to extract patches with high ecosystem service function importance level, high ecological sensitivity level and area not less than (or greater than) the set area threshold as stable ecological patches (preliminary ecological patches or alternative ecological patches) based on the ecosystem service function importance level and ecological sensitivity level;

[0025] Screening module: used to conduct landscape connectivity analysis on stable ecological patches, and select stable ecological patches whose patch importance index is greater than the set value as ecological sources (final ecological sources, or stable ecological sources).

[0026] Furthermore, the system may also include a determination module, which is used to determine the stability level of the selected ecological source based on the landscape connectivity analysis results, and form an ecological source identification result with a stability level.

[0027] Preferably, a basic database is constructed based on the basic data obtained after preprocessing, and the basic database retains or does not retain the original data and the preprocessing records of the original data.

[0028] Preferably, a network communication device may be provided to access a related external database / server through the network to obtain the original data that can be directly obtained from the external database.

[0029] The present invention identifies ecological sources based on the comprehensive evaluation of ecosystem services and ecological sensitivity, combines the evaluation with existing research methods, selects ecosystems and their distribution areas that need to be protected, evaluates habitat quality based on the importance of ecosystem service functions and ecological sensitivity, extracts ecologically significant patches through the analysis results of ecosystem service function importance and ecological sensitivity, sets a threshold for the minimum area of ​​ecological sources, and conducts landscape connectivity evaluation. According to the evaluation results, patches with high landscape connectivity are selected as the final identification results of ecological sources, which effectively avoids the subjectivity of human selection, makes the results more scientific and reasonable, and has certain operability and universality.

[0030] The present invention incorporates landscape connectivity into the identification of stable ecological sources. By constructing a comprehensive connectivity indicator system covering overall connectivity and potential connectivity, it accurately quantifies the connection efficiency between stable ecological patches, providing a powerful tool for identifying key ecological regions where ecosystem connectivity and integrity are particularly prominent.

[0031] The calculation process of the present invention is concise, efficient and highly flexible, which can help decision makers quickly and accurately lock in key ecological areas in dynamic environmental changes, provide valuable spatial guidance for ecological planning work, and is of great significance for promoting the refinement and efficiency of ecological protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a flow chart of the ecological source identification method involved in the present invention;

[0033] Figure 2 It is a schematic diagram of the architecture of the ecological source identification system involved in the present invention;

[0034] Figure 3 is a diagram of the calculation result of the ecosystem service function importance evaluation in an embodiment of the present invention;

[0035] Figure 4 is a graph of the calculation results of the ecological sensitivity assessment in an embodiment of the present invention;

[0036] Figure 5 It is a preliminary identification stable ecological patch distribution map in an embodiment of the present invention;

[0037] Figure 6 This is a distribution map of stable ecological sources in an embodiment of the present invention. DETAILED DESCRIPTION

[0038] See also Figure 1-Figure 6 This paper adopts the method of multi-model collaboration and multi-evaluation coupling. Through the evaluation of the importance of ecosystem service functions and the evaluation of ecological sensitivity, it objectively depicts the ecological change characteristics of the study area in the time series, conducts a comprehensive assessment of the regional ecosystem structure and function, and screens out key ecological spaces with a high comprehensive level, thereby identifying stable ecological sources.

[0039] This ecological source identification method includes the following steps:

[0040] Step 1: Obtain relevant data of the study area and perform data preprocessing.

[0041] Obtain relevant data of the study area within the preset time range. For example, select 2000 to 2020 as the study period and obtain land use data every five years; geographic information data includes DEM data (digital elevation model), meteorological data, administrative division data, traffic data and other indicators. Project according to the unified coordinate system and unify the pixel size through the ArcGIS platform to perform data processing and overlay analysis.

[0042] Specifically include:

[0043] ① The land use types in the study area are divided into six categories: cultivated land, forest land, grassland, water area, construction land and unused land;

[0044] ②Use ArcGIS 10.8 software to process the DEM data into grid mosaics, use the clipping tool to clip the DEM data according to the study area, calculate and analyze the grid surface, and obtain the slope and aspect data;

[0045] ③ Use ENVI remote sensing processing software to perform coordinate conversion, cropping, and calibration on remote sensing images to obtain remote sensing images of the study area, and obtain vegetation coverage through the calculation method of normalized vegetation index (NDVI);

[0046] ④ The original data on precipitation meteorology, vegetation net primary productivity (NPP), transportation network, water system, etc. are projected according to a unified coordinate system through the ArcGIS platform, with unified pixel size for data processing and overlay analysis.

[0047] Step 2: Evaluation of the importance of ecosystem service functions.

[0048] Three single indicators, namely water conservation, soil and water conservation, and biodiversity maintenance, were selected for superposition analysis to study the importance of regional ecosystem service functions. The multi-factor weighted superposition method was used to evaluate the overall ecological function of the study area.

[0049] Specifically include:

[0050] ①Evaluate water conservation function

[0051] The water conservation capacity is calculated using the NPP index method, and the ecosystem water conservation service capacity index is used as the evaluation index. The calculation formula is:

[0052] WR=NPP mean ×F sic ×F pre ×(1-F sio )

[0053] Where: WR is water conservation capacity; NPP mean is the average annual net primary productivity of vegetation; F sic is the soil seepage factor; F pre is the annual average precipitation factor; F sio is the slope factor.

[0054] ② Evaluation of soil and water conservation function

[0055] The soil and water conservation function mainly involves the interaction of factors such as topography, soil type, and vegetation coverage. The soil and water conservation amount is calculated using the general soil and water loss equation. The calculation formula is:

[0056] S pro =NPP mean ×(1-K)×(1-F slo )

[0057] Where: S pro Capacity index for soil and water conservation services; NPP meanis the average annual net primary productivity of vegetation; K is the soil erosion factor; F slo is the slope factor.

[0058] ③Evaluation of biodiversity maintenance function

[0059] Net primary productivity represents the energy value required for the growth, development and reproduction of microorganisms in an ecosystem, and is also the material basis for the survival and development of other organisms. The biodiversity function of the study area is determined by quantitative analysis of NPP, and the calculation formula is:

[0060] S bio =NPP mean ×F pre ×F tem ×(1-F alt )

[0061] Where: S bio Biodiversity Conservation Performance Index; NPP mean is the average annual net primary productivity of the study area; F pre is the annual average precipitation factor; F tem is the annual average temperature factor; F alt is the altitude factor.

[0062] ④Integrated evaluation of the importance of ecosystem service functions

[0063] The weight of each factor (each single factor) in the integrated evaluation of ecological function importance is determined according to the importance of each ecological function to the ecosystem. For example, in one example, the weights of water conservation factor, soil and water conservation factor and biodiversity maintenance factor are finally determined to be 0.4, 0.3 and 0.3 respectively. ArcGIS 10.8 software is used for weighted calculation to obtain the evaluation result data.

[0064] The above evaluation results are divided into 5 categories (5 levels) according to the natural breakpoint method, that is, further divided into five levels: high, relatively high, medium, relatively low and low.

[0065] Step 3: Ecological sensitivity assessment.

[0066] Specifically include:

[0067] ① Determination and assignment of ecological sensitivity factors

[0068] Factors with greater impact on the ecological sensitivity of the study area are selected. Usually, six indicators, including elevation, slope, vegetation coverage, annual precipitation, water area and land use type, are set to conduct a comprehensive evaluation of the ecological sensitivity. The ecological sensitivity factors are reclassified through ArcGIS10.8, and sensitivity values ​​are assigned one by one according to the ecological sensitivity factor evaluation table to obtain the reclassification evaluation results of different ecological sensitivity factors.

[0069] Ecological sensitivity factor evaluation table

[0070]

[0071] ② Setting of ecological evaluation factor weights

[0072] The weights of ecological sensitivity evaluation factors were determined using the analytic hierarchy process, and the relative size of each factor in the overall ecological sensitivity was comprehensively judged based on the regional nature, characteristics and evaluation objectives of the study area. The six ecological sensitivity factors were scored and weights were determined through the analytic hierarchy process and expert consultation.

[0073] Yaahp software was used to construct a hierarchical model. After checking that the model was correct, matrix judgment was performed, and the factors in each row and column were compared pairwise and scored to obtain the weight value of each factor.

[0074] Ecological sensitivity factor weight table

[0075]

[0076] ③Analysis of comprehensive results of ecological sensitivity

[0077] Using the raster calculator in ArcGIS 10.8 software, the data of each factor (each single factor) was input in turn according to the weight to obtain the evaluation result data. The data was classified using the natural fracture method to obtain the ecological sensitivity analysis results of the study area, providing data support for the selection of ecological source areas.

[0078] Step 4: Preliminary extraction of ecological patches

[0079] The ecological source (stable ecological patch) was initially extracted by the intersection of the high-ecosystem service evaluation and the high-ecological sensitivity patches. The ecological source obtained by this method not only reflects the ability of the ecosystem to continuously provide ecosystem services, but also reflects the response of the source itself to changes in the external environment.

[0080] ArcGIS 10.8 software was used to extract the most important areas of ecosystem service functions and the areas with the highest ecological sensitivity, and an intersection analysis was performed. To avoid the fragmentation of the ecological security pattern, the piecewise linear regression method was used to eliminate areas with an area smaller than a certain threshold (e.g., 10 km 2 ) patches, and initially obtained ecological patches.

[0081] Step 5: Landscape connectivity assessment

[0082] The degree of patch connectivity of the screened preliminary ecological patches is calculated to identify the core area patches that are crucial to ecological connectivity and ultimately determine the ecological source.

[0083] Using Conefor 2.6 software, three indices, including overall connectivity IIC, possible connectivity PC, and plaque importance dPC, were selected for calculation. The formula is as follows:

[0084] Overall Connectedness Index (IIC):

[0085]

[0086] Where n is the total number of relevant patches in the study area; a i and a j is the area of ​​patch i and patch j; nl ij is the number of shortest path connections between patch i and patch j; A L is the property value for the entire landscape.

[0087] Possible Connectivity Index (PC):

[0088]

[0089] Where n is the total number of relevant patches in the study area; a i and a j is the area of ​​patch i and patch j; p ij A is the maximum possibility of species running on all paths between patch i and patch j; L is the attribute value of the entire landscape. PC is the possible connection index, which is the weighted probability of connectivity between two patches.

[0090] Plaque importance index (dPC):

[0091]

[0092] Where dPC is the plaque importance index (or possible connectivity importance value) of any plaque, PC is the possible connectivity index calculated based on all patches; PC remove It is the possible connectivity index calculated based on the remaining patches after removing the patch. dPC is the basis for identifying the importance of patches.

[0093] Step 6: Identify and extract the final ecological source

[0094] Set the patch connectivity distance threshold to 500m (or other values ​​set according to actual conditions), the connectivity probability threshold to 0.5 (or other values ​​set according to actual conditions), and within the range of patches and distance thresholds, select patches with dPC values ​​greater than 0.5 as the final ecological source.

[0095] Unless otherwise specified or when one preferred or optional technical means is a further limitation of another technical means, the preferred and optional technical means disclosed in the present invention can be arbitrarily combined to form several different specific implementation methods.

Claims

1. Ecological source identification methods based on ecosystem services and ecological sensitivity assessment, including: Obtain the original data for ecosystem service function importance evaluation and ecological sensitivity evaluation in the study area within a preset time range, pre-process the original data, and form basic data for ecosystem service function importance evaluation and ecological sensitivity evaluation; Based on the basic data, the importance of ecosystem service functions is evaluated and analyzed to obtain the data of each evaluation index used for the importance of ecosystem service functions. The corresponding comprehensive evaluation data is obtained by weighted summation based on the data of each evaluation index and the weight of each evaluation index. The comprehensive evaluation data is graded to obtain the importance level of ecosystem service functions. Based on the basic data, ecological sensitivity evaluation and analysis are carried out to obtain the data of each evaluation factor used for ecological sensitivity evaluation and analysis, and each evaluation factor is graded according to the data of each evaluation factor. The value of each evaluation factor is obtained according to the grading of each evaluation factor, and the weighted sum is performed according to the value of each evaluation factor and the weight of each evaluation factor to obtain the corresponding comprehensive evaluation data, and the comprehensive evaluation data is graded to obtain the ecological sensitivity level; Extract patches with high importance of ecosystem service functions, high ecological sensitivity and an area not less than or greater than the set area threshold as stable ecological patches; The landscape connectivity analysis was conducted on the stable ecological patches, and the stable ecological patches whose patch importance index was greater than the set value were selected as ecological sources.

2. The ecological source identification method according to claim 1, characterized in that For the selected ecological source areas, the stability level of the ecological source areas is determined based on the results of landscape connectivity analysis.

3. The ecological source identification method according to claim 1, characterized in that The evaluation indicators used to evaluate the importance of ecosystem service functions are water conservation capacity, soil and water conservation service capacity index and biodiversity maintenance service capacity index.

4. The ecological source identification method according to claim 1, characterized in that The evaluation factors used for ecological sensitivity assessment analysis are elevation, slope, distance to water source buffer zone, vegetation coverage, average annual precipitation and land use type.

5. The ecological source identification method according to claim 1, characterized in that The weight calculation of each evaluation factor is implemented based on the hierarchical analysis method, and the weight of each evaluation factor is determined according to the results of expert consultation.

6. The ecological source identification method according to claim 1, characterized in that Implement ecosystem service function importance evaluation and ecological sensitivity evaluation analysis with a uniform pixel size.

7. Ecological source identification system based on ecosystem services and ecological sensitivity assessment, characterized by The ecological source identification is implemented by using the ecological source identification method based on ecosystem service function importance evaluation and ecological sensitivity evaluation as described in any one of claims 1 to 7.

8. The ecological source identification system according to claim 7, characterized in that include: Preprocessing module: used to obtain the original data for ecosystem service function importance evaluation and ecological sensitivity evaluation in the study area within a preset time range, preprocess the original data, and form the basic data for ecosystem service function importance evaluation and ecological sensitivity evaluation; Calculation module: used to evaluate and analyze the importance of ecosystem service functions based on basic data, obtain the data of each evaluation index used for the evaluation of the importance of ecosystem service functions, perform weighted summation based on the data of each evaluation index and the weight of each evaluation index, obtain the corresponding comprehensive evaluation data, perform grading based on the comprehensive evaluation data, and obtain the importance level of ecosystem service functions; Based on the basic data, ecological sensitivity evaluation and analysis are carried out to obtain the data of each evaluation factor used for ecological sensitivity evaluation and analysis, and each evaluation factor is graded according to the data of each evaluation factor. The value of each evaluation factor is obtained according to the grading of each evaluation factor, and the weighted sum is performed according to the value of each evaluation factor and the weight of each evaluation factor to obtain the corresponding comprehensive evaluation data, and the comprehensive evaluation data is graded to obtain the ecological sensitivity level; Extraction module: used to extract patches with high ecosystem service function importance level, high ecological sensitivity level and area not less than or greater than the set area threshold as stable ecological patches based on the ecosystem service function importance level and ecological sensitivity level; Screening module: used to conduct landscape connectivity analysis on stable ecological patches, and select stable ecological patches whose patch importance index is greater than the set value as ecological sources.

9. The ecological source identification system according to claim 7, characterized in that It also includes a determination module, which is used to determine the stability level of the selected ecological source based on the landscape connectivity analysis results, and form an ecological source identification result with a stability level.

10. The ecological source identification system according to claim 7, characterized in that Based on the basic data obtained after preprocessing, a basic database is constructed, and the basic database retains or does not retain the original data and the preprocessing records of the original data.

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