A method for constructing an urban carbon sink space ecological network

Abstract

The present application relates to carbon sink space ecological technical field, and disclose a kind of based on urban carbon sink space ecological network construction method, step S1, according to land use data and net carbon sink coefficient carry out net carbon sink quantity calculation;Step S2, by morphological landscape pattern analysis method, extract carbon sink space ecological source patch;Step S3, according to the theory of landscape connectivity to the carbon sink space ecological source patch extracted is analyzed, and carbon sink space ecological source is screened out;Step S4, using minimum cumulative resistance model technology, through minimum cost path and interaction force, carbon sink corridor is identified;Step S5, to carbon sink space ecological source, carbon sink corridor is judged importance, and constructs urban carbon sink space ecological network.The present application is analyzed by carbon sink quantity, landscape pattern, landscape connectivity and minimum cumulative resistance model, forms urban carbon sink ecological network, and the carbon sink space pattern constructed is more accurate, improves the rationality and scientificity of city planning.

Description

Technical Field

[0001] This invention relates to the field of carbon sink space ecological technology, and more specifically to a method for constructing an urban carbon sink space ecological network. Background Technology

[0002] The urbanization process has caused changes in the function and spatial structure of urban ecosystems, leading to a decrease in the carbon sequestration capacity and efficiency of urban ecological spaces. Since the proposal of the landscape ecological security pattern, various scholars have conducted a large number of studies on the optimization of urban land use landscape patterns, urban ecological sensitivity, urban ecological service functions, and urban heat island effect. The regional scale has also gradually expanded from single cities to include urban agglomerations, islands, geological disaster sensitive areas, counties, scenic spots, etc. The construction of ecological networks can effectively improve the ecological environment stability of the entire region.

[0003] Research on urban ecological networks focuses on urban green space systems and green spaces. As the only land space in a city with carbon sink function, ecological space plays an irreplaceable role in maintaining regional carbon balance. However, research on low-carbon urban ecological networks is still in the exploratory stage. The stability of urban carbon sink function can be directly reflected in the carbon sink function of urban landscape. Currently, urban carbon sink space cannot be constructed quickly and accurately. Summary of the Invention

[0004] In order to overcome the above-mentioned defects of the prior art, the embodiments of the present invention provide a method for constructing an ecological network based on urban carbon sink space to solve the technical problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for constructing an urban carbon sink spatial ecological network, comprising the following steps:

[0006] Step S1: Calculate the net carbon sink based on land use data and net carbon sink coefficient;

[0007] Step S2: Extract carbon sink space ecological source patches using morphological landscape pattern analysis methods;

[0008] Step S3: Analyze the extracted carbon sink space ecological source patches according to the landscape connectivity theory, and screen out the carbon sink space ecological source areas;

[0009] Step S4: Using the minimum cumulative resistance model technique, carbon sink corridors are identified through the minimum cost path and interaction forces;

[0010] Step S5: Assess the importance of carbon sink space ecological sources and carbon sink corridors, and construct an urban carbon sink space ecological network.

[0011] In a preferred embodiment, the formula for calculating the carbon sink of land use type is as follows: In the formula V S For the calculated carbon sink, S represents the land use type area; k represents the net carbon sink coefficient.

[0012] In a preferred embodiment, during morphological landscape pattern analysis, carbon sink space ecological source patches are identified. In this identification, woodland, grassland, water bodies, shrubland, and wetlands are used as the foreground, while cultivated land, artificial surfaces, and bare land are used as the background. The foreground and background data are imported into Guidos Toolbox and converted into binary images. The binary images are then segmented into non-overlapping landscape types at the pixel level using the eight-neighborhood method. The carbon sink amount of each identified landscape type is compared with its internal threshold in Guidos Toolbox. If the carbon sink amount of a identified landscape type is higher than the internal threshold, that landscape type is considered a carbon sink space ecological source patch; otherwise, it is not considered a carbon sink space ecological source patch.

[0013] In a preferred embodiment, when extracting the ecological source areas of carbon sink spaces, landscape connectivity is used for identification. Landscape connectivity includes potential connectivity (dPC) within the carbon sink space and overall connectivity (dIIC) within the carbon sink space. The formula for calculating potential connectivity (dPC) within the carbon sink space is as follows: In the formula The formula for calculating the overall connectivity dIIC within the carbon sink space is: (The formula is not provided in the original text.) In the formula S i and S j The areas of carbon sequestration ecological source patches i and j are respectively, C ij S represents the total connectivity of carbon sink ecological source patches i and j along the shortest path. e denoted as the total area of ​​landscape elements within the region; n represents the total number of patches in landscape surface e. Landscape connectivity analysis is performed on the patches of carbon sink space ecological source areas, and patches of carbon sink space ecological source areas with dPC and dIIC greater than 1 are selected as carbon sink space ecological source areas.

[0014] In a preferred embodiment, when calculating the minimum cumulative resistance surface of the carbon sink space, the resistance value is first calculated, and the calculation formula is as follows: In the formula, MCR is the minimum cumulative resistance value; D ij R is the distance from ecological source j to target unit i; iAs the resistance coefficient, elevation, slope, NDVI, and current land use status were selected as resistance factors. The analytic hierarchy process (AHP) was used to score each resistance factor and obtain the weight of each resistance factor. In ArcGIS 10.6, the reclassification tool was used to divide elevation, slope, and NDVI into 5 levels, and land use type was reclassified into 5 primary categories to construct the minimum cumulative resistance surface of carbon sink space.

[0015] In a preferred embodiment, the formula for calculating the interaction forces within the carbon sink space is:

[0016]

[0017] In the formula G ij N represents the interaction force between source sites i and j. i With N j These are the weighting coefficients for carbon sink land i and j, respectively, D ij P represents the standardized distance cost value of the potential carbon transport corridor between carbon sink sites i and j; i and P j S represents the total distance cost between carbon sink sites i and j. i With S j Let L represent the area of ​​carbon sink land i and j respectively. ij L represents the cumulative distance cost of the potential carbon transport corridor between carbon sink sites i and j. max This represents the maximum distance cost of all potential carbon transport corridors between various carbon sink sites.

[0018] In a preferred embodiment, after landscape connectivity identification, carbon sink spatial ecological source patches with interaction forces greater than 10 and dIIC greater than 5 are extracted as key carbon sink spatial ecological source patches, and carbon sink spatial ecological source patches with interaction forces greater than 5 and dIIC less than 5 are selected as important carbon sink spatial ecological source patches.

[0019] In a preferred embodiment, key carbon sink ecological source areas and important carbon sink ecological source areas identified after landscape connectivity are used as sources and targets in cost distance, and carbon sink corridors of carbon sink ecological source areas are generated using the cost distance and cost path tools in ArcGIS 10.6-Spatial Analyst module.

[0020] In a preferred embodiment, the minimum cumulative resistance value (MCR) and the interaction force (G) within each carbon sink corridor are extracted. ij The possible connectivity dPC and the overall connectivity dIIC are correlated to calculate the hierarchical value F. The formula for calculating the hierarchical value F is as follows: In the formula, k1 and k2 are both weights, and 0≤k1≤1, 0≤k2≤1, k1+k2=1. The calculated graded values ​​F are arranged in descending order, and the importance of the carbon sink corridor corresponding to the graded value F is proportional to the order of the graded values ​​F.

[0021] In a preferred embodiment, the importance of the carbon sink space ecological source area is calculated using a performance value d, and the formula for calculating the performance value d is as follows: d represents the calculated importance performance value of the carbon sink space ecological source area. The importance of the carbon sink space ecological source area is arranged in descending order according to the value of d. The carbon sink space ecological source area, carbon sink space ecology and carbon sink corridor are used to construct the carbon sink space pattern.

[0022] The technical effects and advantages of this invention are as follows:

[0023] This invention uses a comprehensive analysis of carbon sink volume, landscape pattern, landscape connectivity, and minimum cumulative resistance model to extract the ecological source areas of carbon sink space. Based on the MCR model, it obtains the minimum cumulative resistance surface of carbon sink and identifies carbon sink corridors, forming an urban carbon sink ecological network. The resulting carbon sink spatial pattern is more accurate, improving the rationality and scientific nature of urban planning. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall process of the present invention.

[0025] Figure 2 This is a schematic diagram of the current land use situation according to the present invention.

[0026] Figure 3 This is a schematic diagram of the carbon sink spatial landscape type of the present invention.

[0027] Figure 4 This is a schematic diagram showing the distribution of carbon sink corridors and carbon sink space ecological source areas at various levels according to the present invention. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. In addition, the forms of the various structures described in the following embodiments are merely illustrative. The method for constructing an urban carbon sink spatial ecological network involved in the present invention is not limited to the structures described in the following embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1

[0030] Reference Figure 1 This invention provides a method for constructing an urban carbon sink spatial ecological network, comprising the following steps:

[0031] Step S1: Calculate the net carbon sink based on land use data and net carbon sink coefficient;

[0032] Step S2: Extract carbon sink space ecological source patches using morphological landscape pattern analysis methods;

[0033] Step S3: Analyze the extracted carbon sink space ecological source patches according to the landscape connectivity theory, and screen out the carbon sink space ecological source areas;

[0034] Step S4: Using the minimum cumulative resistance model technique, carbon sink corridors are identified through the minimum cost path and interaction forces;

[0035] Step S5: Assess the importance of carbon sink space ecological sources and carbon sink corridors, and construct an urban carbon sink space ecological network.

[0036] In this embodiment, the landscape pattern and carbon sink volume of carbon sink land are analyzed, the ecological source areas of carbon sink space are extracted, the minimum cumulative resistance surface of carbon sink is obtained based on the MCR model, and carbon sink corridors are identified to form an urban carbon sink ecological network. The final constructed urban carbon sink spatial pattern is more accurate. Future urban and rural planning should take carbon balance as the overall goal, so that urban space can increase the carbon cycle and carbon storage capacity of the ecosystem on the basis of meeting the layout and laws of social and economic development, thereby providing a basic pattern for ecological restoration and comprehensive land management for carbon sequestration and increase.

[0037] Furthermore, the formula for calculating the carbon sequestration of land use types is as follows: In the formula V S For the calculated carbon sink, S represents the land use type area; k represents the net carbon sink coefficient. Land use type determines the type of socio-economic activities in that space and is the best carrier for spatializing and visually representing the regional carbon sink. Grassland, woodland, water bodies, and wetlands can be the main sources of carbon sink for urban land use types. In this application, different land use types have different carbon sink coefficients when calculating carbon sink, and the final calculated carbon sink is more accurate.

[0038] Land use type and carbon sink coefficient table

[0039]

[0040] Furthermore, during morphological landscape pattern analysis, carbon sink space ecological source patches are identified. In this identification process, woodland, grassland, water bodies, shrubland, and wetlands are used as the foreground, while cultivated land, artificial surfaces, and bare land are used as the background. The foreground and background data are imported into Guidos Toolbox and converted into binary images. The binary images are then segmented into non-overlapping landscape types at the pixel level using the eight-neighborhood method. The carbon sink amount of each identified landscape type is compared with its internal threshold in Guidos Toolbox. If the carbon sink amount of a landscape type is higher than the internal threshold, that landscape type is considered a carbon sink space ecological source patch; otherwise, it is not considered a carbon sink space ecological source patch.

[0041] In this embodiment, woodlands, grasslands, water bodies, shrublands, and wetlands are used as foreground because they can generate natural carbon sinks and have carbon storage capacity. Cultivated land, artificial surfaces, and bare land do not have natural carbon sink generation or carbon storage capacity, so they are used as background. The carbon sink amount calculated for each landscape type is sufficiently accurate. After comparing it with a threshold, if the carbon sink amount is higher than the internal threshold, the landscape type is considered as a carbon sink spatial ecological source patch, indicating that the carbon sink amount of this landscape type is relatively high and can be used as a carbon sink spatial ecological source patch. In addition, it should be noted that importing foreground and background data into Guidos Toolbox to convert it into a binary image, and segmenting the binary image into non-overlapping landscape types at the pixel level using the eight-neighborhood method, is a prior art method for those skilled in the art, and this application does not limit it in detail.

[0042] Furthermore, when extracting ecological source areas of carbon sink spaces, landscape connectivity is used for identification. Landscape connectivity includes potential connectivity (dPC) within the carbon sink space and overall connectivity (dIIC) within the carbon sink space. The formula for calculating potential connectivity (dPC) within the carbon sink space is as follows: In the formula The formula for calculating the overall connectivity dIIC within the carbon sink space is: (The formula is not provided in the original text.) In the formula S i and S j The areas of carbon sequestration ecological source patches i and j are respectively, C ij S represents the total connectivity of carbon sink ecological source patches i and j along the shortest path. e denoted as the total area of ​​landscape elements within the region; n represents the total number of patches in landscape surface e. Landscape connectivity analysis is performed on the patches of carbon sink space ecological source areas, and patches of carbon sink space ecological source areas with dPC and dIIC greater than 1 are selected as carbon sink space ecological source areas.

[0043] In this embodiment, landscape connectivity represents the degree of convenience or obstruction of energy flow in a landscape. Good connectivity indicates that the area plays an important role in maintaining the stability of the regional ecosystem. The larger the ecological patch, the better the habitat quality, and the greater the possibility of it serving as a carbon sink ecological source. The larger the dPC value obtained from landscape connectivity analysis, the higher the importance of the core area patch, and vice versa. Overall connectivity dIIC can express the overall energy flow in the region. Therefore, carbon sink ecological source patches with dPC and dIIC greater than 1 are selected as carbon sink ecological source areas. The selected areas have good energy flow and high importance.

[0044] Furthermore, when calculating the minimum cumulative resistance surface of carbon sink space, the resistance value is calculated first, and the calculation formula is as follows: In the formula, MCR is the minimum cumulative resistance value; D ij R is the distance from ecological source j to target unit i; i As the resistance coefficient, elevation, slope, NDVI, and current land use status were selected as resistance factors. The analytic hierarchy process (AHP) was used to score each resistance factor and obtain the weight of each resistance factor. In ArcGIS 10.6, the reclassification tool was used to divide elevation, slope, and NDVI into 5 levels, and land use type was reclassified into 5 primary categories to construct the minimum cumulative resistance surface of carbon sink space.

[0045] In this embodiment, different resistance factors have different degrees of influence on urban carbon sink space. Based on the degree of influence of resistance factors on urban carbon sink space, the calculated resistance surface is more accurate and the minimum cumulative resistance surface can be found. This makes it easier to find the ecological source of carbon sink space with high carbon sink volume, and thus facilitates the establishment of the final urban carbon sink space pattern. In addition, it should be noted that the use of reclassification tools in ArcGIS 10.6 is a conventional technical means in this field, and this application does not limit it in detail.

[0046] Resistance factor classification and resistance coefficient table

[0047]

[0048] Furthermore, the formula for calculating the interaction forces within the carbon sink space is as follows:

[0049]

[0050] In the formula G ij N represents the interaction force between source sites i and j. i With N j These are the weighting coefficients for carbon sink land i and j, respectively, D ij P represents the standardized distance cost value of the potential carbon transport corridor between carbon sink sites i and j; iand P j S represents the total distance cost between carbon sink sites i and j. i With S j Let L represent the area of ​​carbon sink land i and j respectively. ij L represents the cumulative distance cost of the potential carbon transport corridor between carbon sink sites i and j. max To determine the maximum distance cost of all potential carbon flow corridors between carbon sink lands, and after landscape connectivity identification, carbon sink spatial ecological source patches with interaction forces greater than 10 and dIIC greater than 5 are extracted as key carbon sink spatial ecological source patches, and carbon sink spatial ecological source patches with interaction forces greater than 5 and dIIC less than 5 are identified as important carbon sink spatial ecological sources.

[0051] In this embodiment, the magnitude of the interaction force reflects the importance of potential carbon flow corridors between source areas. The determination of ecological source areas mainly depends on the size of the patches and the connectivity level between the patches. This application considers the interaction force and the overall connectivity dIIC within the carbon sink space, which allows for the selection of core patches that can serve as ecological source areas for carbon sink spaces. Therefore, this application can quickly extract key and important ecological source areas for carbon sink spaces.

[0052] Furthermore, after landscape connectivity identification, key carbon sink spatial ecological source areas and important carbon sink spatial ecological source areas are used as sources and targets in cost distance. The cost distance and cost path tools in ArcGIS 10.6-Spatial Analyst module are used to generate carbon sink corridors for carbon sink spatial ecological source areas.

[0053] Furthermore, the minimum cumulative drag value (MCR) and interaction force (G) within each carbon sink corridor are extracted. ij The possible connectivity dPC and the overall connectivity dIIC are correlated to calculate the hierarchical value F. The formula for calculating the hierarchical value F is as follows: In the formula, k1 and k2 are weights, and 0≤k1≤1, 0≤k2≤1, k1+k2=1. The calculated grading values ​​F are arranged in descending order, and the importance of the carbon sink corridor corresponding to the grading value F is proportional to the order of the grading values ​​F. The importance of the carbon sink space ecological source area is calculated using the performance value d, and the formula for calculating the performance value d is as follows: d represents the calculated importance performance value of the carbon sink space ecological source area. The importance of the carbon sink space ecological source area is arranged in descending order according to the value of d. The carbon sink space ecological source area, carbon sink space ecology and carbon sink corridor are used to construct the carbon sink space pattern.

[0054] In this embodiment of the application, the minimum cumulative resistance value MCR and the interaction force G within the carbon sink corridor are extracted. ijPossible connectivity dPC and global connectivity dIIC, interaction force G ij The values ​​of potential connectivity (dPC) and overall connectivity (dIIC) indicate that the higher the value of these three values, the higher the carbon sink volume and the faster the flow rate within the carbon sink corridor, and the greater its importance. However, the minimum cumulative resistance (MCR) has a negative impact. Therefore, in the formula of this application, the MCR is used as the denominator. The final calculated grading value F can accurately express the importance of the carbon sink corridor. The higher the grading value, the more important the carbon sink corridor. The importance of the carbon sink space ecological source area is arranged in descending order of the performance value d. Finally, the carbon sink space ecological source area, carbon sink space ecology, and carbon sink corridor are constructed to form a carbon sink space pattern more accurately.

[0055] Example 2

[0056] Reference Figure 2 The study area covers the main urban area of ​​Nanning City, including Liangqing District, Jiangnan District, Qingxiu District, Xingning District, Xixiangtang District, and Yongning District, with latitude and longitude between 107°76′ and 108°86′ east longitude and 22°21′ and 23°12′ north latitude, covering a total area of ​​6447 km². 2 The urbanization rate of Nanning City has reached 68.9%, and its current utilization status is as follows: Figure 2 As shown.

[0057] Reference Figure 3 Land use types with natural carbon sinks and high carbon storage capacity, such as woodland, grassland, water bodies, shrubland, and wetlands, were extracted as foreground and assigned a value of 2. Cultivated land, artificial surfaces, and bare land were used as background and assigned a value of 1. The MSPA pixel size was set to 30 m × 30 m, and the edge width was 1 (actual width was 30 m). The analysis results are as follows: Figure 3 The seven landscape types are shown in the table below.

[0058] Table of Area and Percentage of Seven Landscape Types

[0059]

[0060] The core area, representing the ecological source of urban carbon sink space, accounts for the largest proportion among the seven types of prospective landscapes, totaling 2801.62 km², representing 87.32% of the prospective value and 43.45% of the study area. The land use types are mainly forest, water bodies, and wetlands, which are also areas with relatively high carbon sink volumes. The peripheral area, covering 280.62 km², serves as a transition between the core area and non-ecological landscape elements, accounting for 4.35% of the prospective value. Branch lines and bridging are important "bridges" connecting various core areas, accounting for only 0.87% of the prospective value. In the urban carbon sink spatial ecological network, branch lines and bridging are important corridors promoting network integrity. These branch lines and bridging are scattered among the various core areas within the city center, indicating that while there are internal and external connections between the core areas, they are relatively weak and susceptible to disruption due to human activities. Spatially, important and large contiguous core areas are distributed in the north, south, and west of the study area. These areas are rich in ecological resources and can provide a guarantee for enhancing the city's carbon sink capacity. The patches in the southwestern core area are relatively scattered, and the landscape in the east is difficult to connect with other areas, such as... Figure 3 The areas with higher net carbon sinks in the study area are located in the northeast and southwest. The main land use types are forested land, sparse forest land, and dry land, covering important mountain forests, scenic spots, nature reserves and reservoirs. These areas are less affected by human disturbance and have a good ecological carbon sink base.

[0061] Net carbon sinks of land use types were divided into six levels using the natural discontinuity method. The three levels with the largest net carbon sinks were then intersected with the core areas of landscape pattern types. From this, landscape type patches that are significant for patch connectivity were selected. To eliminate the interference of smaller patches on the overall pattern stability, the areas larger than 5 km² in the intersection results were extracted, taking into account factors such as the study area and the patch area in the core area. 2 42 core area patches;

[0062] By ranking the ecological core area patches according to their importance (dIIC) and potential connectivity (dPC) based on landscape connectivity, core area patches that can serve as carbon sink ecological sources were selected. Through landscape connectivity index analysis, 27 core area patches with dPC and dIIC greater than 1 were selected as carbon sink ecological sources. Combined with the evaluation results of the gravity model matrix, 11 core area patches with interaction forces greater than 10 and dIIC greater than 5 were identified as key carbon sink ecological sources; 16 core area patches with interaction forces greater than 5 and dIIC less than 5 were identified as important carbon sink ecological sources.

[0063] The land use types of carbon sink ecological source areas are mainly forest and grassland, totaling 1249.72 km2. The southern carbon sink ecological source areas are relatively concentrated, but human interference has led to fragmentation of the patch edges. The northern carbon sink ecological source areas are long and narrow, which can improve the connectivity between the northern carbon sink ecological source areas, improve the ecological carbon sink base, and increase the regional carbon sink volume. The key carbon sink ecological source areas are distributed on the north and south sides of the study area, far away from the urban built-up area. These patches are large and have high carbon sink ecological service value, but the distance between these patches is far. At the same time, the central carbon sink ecological source areas are empty, and the connectivity is relatively unstable. The important carbon sink ecological source areas connect the urban built-up area and the key carbon sink ecological source areas. Due to the strong socio-economic activities, their internal fragmentation is strong.

[0064] Reference Figure 4 Eleven key carbon sink source patches and sixteen important carbon sink source patches, identified through landscape connectivity analysis, were used as the source and target in the cost distance calculation. Using the cost distance and cost path tools in ArcGIS 10.6's Spatial Analyst module, carbon sink corridors for the ecological source areas of carbon sink space were generated. Considering urban scale and land area factors, the width of the carbon sink corridors was set to 30 m. The generated carbon sink corridors were then overlaid, merged, and deleted, resulting in 21 key carbon sink corridors and 23 important carbon sink corridors. The results are as follows: Figure 4 As shown.

[0065] By constructing carbon sink corridors through the embodiments of this application, carbon sink corridors in different cities can be calculated quickly and accurately, thereby enabling cities to make more rational plans.

[0066] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0067] In the embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0068] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0069] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0070] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for constructing an urban carbon sink spatial ecological network, characterized in that: Includes the following steps: Step S1: Calculate the net carbon sink based on land use data and net carbon sink coefficient; Step S2: Extract carbon sink space ecological source patches using morphological landscape pattern analysis methods; Step S3: Analyze the extracted carbon sink space ecological source patches according to the landscape connectivity theory and screen out the carbon sink space ecological source areas; Step S4: Using the minimum cumulative resistance model technique, carbon sink corridors are identified through the minimum cost path and interaction forces; Step S5: Assess the importance of carbon sink space ecological sources and carbon sink corridors, and construct an urban carbon sink space ecological network; In morphological landscape pattern analysis, carbon sink space ecological source patches are identified. During the identification of carbon sink space ecological source patches, woodland, grassland, water bodies, shrubland, and wetland are used as foreground, and cultivated land, artificial surfaces, and bare land are used as background. The foreground and background data are imported into Guidos Toolbox and converted into binary images. The binary images are segmented into non-overlapping landscape types at the pixel level using the eight-neighbor method. In Guidos Toolbox, the carbon sink amount of the identified landscape type is compared with its internal threshold. When the carbon sink amount of the identified landscape type is higher than the internal threshold, the landscape type is identified as a carbon sink space ecological source patch. When the carbon sink amount of the identified landscape type is not higher than the internal threshold, the landscape type is not identified as a carbon sink space ecological source patch. When identifying ecological source areas of carbon sink spaces, landscape connectivity is used for identification. Landscape connectivity includes potential connectivity (dPC) within the carbon sink space and overall connectivity (dIIC) within the carbon sink space. The formula for calculating potential connectivity (dPC) within the carbon sink space is as follows: In the formula The formula for calculating the overall connectivity dIIC within the carbon sink space is: (The formula is not provided in the original text.) In the formula S i and S j The areas of carbon sequestration ecological source patches i and j are respectively, C ij S represents the total connectivity of carbon sink ecological source patches i and j along the shortest path. e denoted as the total area of ​​landscape elements within the region; n represents the total number of patches in landscape surface e. Landscape connectivity analysis is performed on the patches of carbon sink space ecological source area to screen out the patches of carbon sink space ecological source area with dPC and dIIC greater than 1 as carbon sink space ecological source area. Extract the minimum cumulative drag value (MCR) and interaction force (G) within each carbon sink corridor. ij The possible connectivity dPC and the overall connectivity dIIC are correlated to calculate the hierarchical value F. The formula for calculating the hierarchical value F is as follows: In the formula, k1 and k2 are both weights, and 0≤k1≤1, 0≤k2≤1, k1+k2=1. The calculated graded values ​​F are arranged in descending order, and the importance of the carbon sink corridor corresponding to the graded value F is proportional to the order of the graded values ​​F. The importance of carbon sink ecological sources is calculated using an expression value d, and the formula for calculating the expression value d is as follows: d represents the calculated importance performance value of the carbon sink space ecological source area. The importance of the carbon sink space ecological source area is arranged in descending order according to the value of d. The carbon sink space ecological source area, carbon sink space ecology and carbon sink corridor are used to construct the carbon sink space pattern.

2. The method for constructing an urban carbon sink spatial ecological network according to claim 1, characterized in that: The formula for calculating carbon sequestration by land use type is as follows: In the formula V S For the calculated carbon sink, S represents the land use type area; k represents the net carbon sink coefficient.

3. The method for constructing an urban carbon sink spatial ecological network according to claim 1, characterized in that: When calculating the minimum cumulative resistance surface of carbon sink space, the resistance value is calculated first, and the calculation formula is as follows: In the formula, MCR is the minimum cumulative resistance value; D ij R is the distance from ecological source j to target unit i; i As the resistance coefficient, elevation, slope, NDVI, and current land use status were selected as resistance factors. The analytic hierarchy process (AHP) was used to score each resistance factor and obtain the weight of each resistance factor. In ArcGIS 10.6, the reclassification tool was used to divide elevation, slope, and NDVI into 5 levels, and land use type was reclassified into 5 primary categories to construct the minimum cumulative resistance surface of carbon sink space.

4. The method for constructing an urban carbon sink spatial ecological network according to claim 3, characterized in that: The formula for calculating the interaction forces within the carbon sink space is: In the formula G ij N represents the interaction force between source sites i and j. i With N j D represents the weighting coefficients for carbon sink land use i and j, respectively. ij P represents the standardized distance cost value of the potential carbon transport corridor between carbon sink sites i and j; i and P j S represents the total distance cost between carbon sink sites i and j. i With S j Let L represent the area of ​​carbon sink land i and j respectively. ij L represents the cumulative distance cost of the potential carbon transport corridor between carbon sink sites i and j. max This represents the maximum distance cost of all potential carbon transport corridors between various carbon sink sites.

5. The method for constructing an urban carbon sink spatial ecological network according to claim 1, characterized in that: Through landscape connectivity identification, carbon sink spatial ecological source patches with interaction forces greater than 10 and dIIC greater than 5 were extracted as key carbon sink spatial ecological source patches, and carbon sink spatial ecological source patches with interaction forces greater than 5 and dIIC less than 5 were identified as important carbon sink spatial ecological source patches.

6. The method for constructing an urban carbon sink spatial ecological network according to claim 5, characterized in that: After identifying key and important carbon sink ecological sources based on landscape connectivity, carbon sink corridors for these sources are generated using cost distance and cost path tools in ArcGIS 10.6-Spatial Analyst module, with the latter serving as the source and target in the cost distance.

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