Method and system for estimating carbon storage in ecosystems of coal mining subsidence areas

Abstract

The present invention relates to the technical field of mine ecological restoration and carbon reserve estimation, and in particular to a method and system for estimating carbon reserves in ecosystems in coal mining subsidence areas. The method comprises the following steps: S1, dividing the coal mining subsidence area according to land use type, and determining the scope and area of ​​each land use type; S2, dividing the coal mining subsidence area according to spatial state, and forming a land use grid table with a unique code for each land use type; S3, obtaining initial carbon density parameters corresponding to the land use type, calculating the effect of surface subsidence on the carbon density parameters of each sub-area of ​​the coal mining subsidence area, and performing differentiated corrections; S4, calculating the total carbon reserve at different subsidence stages, analyzing the carbon reserve, carbon sequestration, and spatial distribution of each land use type, and comprehensively analyzing the temporal variation characteristics of carbon reserves. The present invention combines land use and subsidence state to analyze carbon density changes, thereby achieving an assessment of the spatiotemporal evolution characteristics of carbon reserves in coal mining subsidence areas.

Description

Technical Field

[0001] The present invention relates to the technical field of mine ecological restoration and carbon reserve estimation, and in particular to a method and system for estimating carbon reserves in an ecosystem in a coal mining subsidence area. Background Art

[0002] Underground coal mining disrupts the stress balance of overlying strata, causing them to collapse, crack, and bend upwards. This eventually propagates to the surface, forming large-scale subsidence known as coal mining subsidence. Current, relatively comprehensive ecosystem carbon stock estimation systems often overlook the subsidence effects of coal mining subsidence, impacting the accuracy of overall ecosystem carbon stock estimates. Furthermore, research on the spatiotemporal evolution of carbon stocks and their carbon sequestration capacity induced by ecological restoration in coal mining subsidence areas is relatively scarce. Therefore, in-depth analysis of the ecological restoration value of coal mining subsidence areas from the perspective of carbon reserves is of great practical significance. Summary of the Invention

[0003] In order to make up for the deficiencies in the prior art, the present invention provides a method for estimating carbon reserves in ecosystems of coal mining subsidence areas based on the InVEST model, comprising the following steps:

[0004] S1. Divide the coal mining subsidence area according to land use type and determine the scope and area of ​​each land use type;

[0005] S2. Divide the coal mining subsidence area into multiple zones according to spatial status, and combine each zone and each land use type to form a land use grid table with a unique code; the spatial status includes: non-subsidence area, active subsidence area, stable subsidence area, and ecological restoration area;

[0006] S3. Obtaining the initial carbon density parameter corresponding to each land use type, calculating the carbon density parameter of each subdivision of the coal mining subsidence area based on the surface subsidence, and performing differential correction;

[0007] S4. Based on the corrected carbon density parameters, the InVEST model was used to calculate the total carbon storage in different collapse stages of the coal mining subsidence area. ArcGIS was used to analyze the total carbon storage in different collapse stages, and the carbon storage, carbon sequestration, spatial distribution of total carbon storage and contribution rate of each carbon pool of each land use type were obtained. The temporal variation characteristics of carbon storage were comprehensively analyzed in combination with the carbon sequestration of each land use type in different collapse stages.

[0008] Furthermore, in order to better implement the present invention, in said S1, the land use types include: cultivated land, forest land, garden land, grassland, water area, construction land and unused land.

[0009] Furthermore, in order to better realize the present invention, in said S2, the method for obtaining the spatial state of the coal mining subsidence area is: using the UAV LiDAR to collect high-precision digital elevation model data and orthophotos of the coal mining subsidence area with a resolution of ≤5m, and combining the ground subsidence monitoring data to correct the terrain undulations of the coal mining subsidence area.

[0010] Furthermore, in order to better implement the present invention, in said S3, the method for obtaining the initial carbon density parameter corresponding to each said land use type is: through publicly published literature related to the area where the coal mining subsidence area is located or conducting on-site sampling and testing.

[0011] Furthermore, in order to better implement the present invention, in said S3, the initial carbon density parameters include: aboveground biomass carbon density C above , belowground biomass carbon density C below , soil carbon density C soil and dead organic matter carbon density C dead .

[0012] Furthermore, in order to better realize the present invention, in said S3, the soil carbon density C soil The method of differential correction is:

[0013] The non-collapsed area is not corrected;

[0014] The soil carbon density in the active collapse area is attenuated according to the original value. The attenuation coefficient is negatively correlated with the collapse depth. The formula is:

[0015] C' soil,t (i, 2) = C soil,0 (i, 2) × e -k×w

[0016] Where i is the i-th land use type; j = 2 is the area of ​​the active collapse zone; w is the surface subsidence, and k = 0.1~0.2 is the coefficient related to the surface subsidence;

[0017] The soil carbon density in the collapsed stable area is linearly restored according to the stable years, and the formula is:

[0018] C' soil,t (i, 3) = C soil,0 (i, 3) × e -k×w +α×Δt1

[0019] Where i is the i-th land use type; j = 3 is the area of ​​the collapse stable zone; Δt1 is the stable period, and α = 0.05~0.15 is the coefficient related to the stable period;

[0020] The soil carbon density in the ecological restoration area is restored by calculating the gain coefficient according to the ecological restoration years. The formula is:

[0021] C' soil,t (i, 4) = C soil,0 (i, 4)×(1+β×ln(Δt2+1))

[0022] Among them, i is the i-th land use type; j=4 is the area of ​​the ecological restoration zone; Δt2 is the restoration period, and β=0.1~0.3 is the coefficient related to the restoration period.

[0023] Furthermore, in order to better realize the present invention, the aboveground biomass carbon density of each subdivision in the coal mining subsidence area is calculated in S3. C above The method for performing differential correction is:

[0024] The non-collapsed area is not corrected;

[0025] The collapse active area and the collapse stable area have changed the stability of the terrain due to collapse, which has caused damage to the ground vegetation. Therefore, the carbon loss is corrected by 5% for every 1° increase in slope. The slope is calculated using DEM data, and the correction formula is:

[0026] C' above,t (i, j) = C above,0 (i, j) × (1-0.05 × s)

[0027] Where i is the i-th land use type; j is the area of ​​the j-th collapse zone; s is the slope;

[0028] The correction of aboveground biomass carbon density in the ecological restoration area is related to multiple factors in the vegetation restoration stage and subsequent management and maintenance. The correction formula is:

[0029] C' above,t (i, 4) = C above,0 (i, 4) × (1-e -2×Δt2 ) × r

[0030] Among them, i is the i-th land use type; j=4 is the area of ​​the ecological restoration zone; Δt2 is the restoration period, and r is the management and protection measure coefficient.

[0031] Furthermore, in order to better realize the present invention, the S3 is used to calculate the carbon density of dead organic matter in the coal mining subsidence area. C dead The method for performing differential correction is:

[0032] The non-collapsed area is not corrected;

[0033] The collapse active zone and the collapse stable zone accelerate the decomposition of litter due to collapse disturbance, and the correction formula is:

[0034] C' dead,t (i, j) = C dead,0 (i, j) × e -0.02×w

[0035] Where i is the i-th land use type; j is the area of ​​the j-th collapse zone; w is the surface subsidence;

[0036] The carbon density of dead organic matter in the ecological restoration area promotes organic matter accumulation through restoration measures, but frequent human interference will destroy the litter layer. The correction formula is:

[0037] C' dead,t (i, 4) = C dead,0 (i, 4)×(1+0.1×Δt2-0.05×Z)

[0038] Where i is the i-th land use type; j = 4 is the area of ​​the ecological restoration zone; Δt2 is the restoration period, and Z is the number of human disturbances during the restoration period.

[0039] Furthermore, in order to better implement the present invention, the above S4 calculates the total carbon reserves of different subsidence stages of the coal mining subsidence area based on the InVEST model, specifically:

[0040] Total carbon storage in coal mining subsidence area at time period t C total,t The calculation formula is:

[0041] C total,t =Σ[ S t (i, j)×( C ' above,t (i, j) + C ' below,t (i, j) + C ' soil,t (i, j) + C ' dead,t (i, j))]

[0042] in, S t (i, j) is the area of ​​the jth subsidence zone of the i-th land use in time period t, C above is the aboveground biomass carbon density; C below is the belowground biomass carbon density; C soil is soil carbon density; Cdead is the carbon density of dead organic matter.

[0043] The present invention also provides a system for estimating carbon reserves in coal mining subsidence area ecosystems based on the InVEST model, comprising:

[0044] The land use type classification module is used to classify the coal mining subsidence area according to the land use type and determine the scope and area of ​​each land use type;

[0045] The spatial partition coding module is used to divide the coal mining subsidence area into multiple partitions according to spatial status, and combine each partition and each land use type to form a land use grid table with a unique code; the spatial status includes: non-collapsed area, active collapse area, stable collapse area and ecological restoration area;

[0046] A carbon density parameter correction module is used to obtain the initial carbon density parameter corresponding to each land use type, calculate the carbon density parameter of each subdivision of the coal mining subsidence area based on the surface subsidence, and perform differentiated corrections;

[0047] The carbon reserve assessment and analysis module is used to calculate the total carbon reserve at different collapse stages in coal mining subsidence areas using the InVEST model based on the corrected carbon density parameters. The total carbon reserve at different collapse stages is analyzed using ArcGIS to obtain statistical tables of carbon reserve, carbon sequestration, spatial distribution of total carbon reserve, and contribution rate of each carbon pool for each land use type. The temporal variation characteristics of carbon reserve are comprehensively analyzed in combination with the carbon sequestration of each land use type at different collapse stages.

[0048] The beneficial effects of the present invention are:

[0049] (1) The present invention creates a uniquely coded raster table by combining land use type and spatial collapse status, so that the research unit takes into account both the natural / utilization attributes of the land and its dynamic process affected by mining, achieving a spatial unit division that is more refined and more realistic than a single-dimensional division, laying an accurate foundation for subsequent analysis; by introducing surface subsidence, the initial carbon density is differentially corrected, taking into account the impact of collapse, a key disturbance factor, on soil structure, vegetation growth, carbon input and output, etc., thereby obtaining a dynamic carbon density parameter that can better reflect the actual carbon storage status of the collapse area, significantly improving the accuracy of the estimation.

[0050] (2) By linking carbon storage changes with specific land use types and subsidence status (e.g., non-subsidence, active subsidence, stable subsidence, and ecological restoration areas), this approach can identify the key drivers of carbon storage loss or gain in different regions. This provides an important scientific basis for developing differentiated land management strategies, ecological restoration measures, and evaluating restoration outcomes, helping to more effectively protect and enhance the carbon sink function of subsidence areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 It is a schematic diagram of the overall process of the present invention;

[0052] Figure 2 A relationship diagram of each subarea of ​​the coal mining subsidence area and the differentiated corrected carbon density of the present invention;

[0053] Figure 3 This is a schematic diagram of module connection of the present invention;

[0054] Figure 4 This is the carbon density parameter table of land use types in coal mining subsidence areas of the present invention (unit: t / hm2);

[0055] Figure 5 This is a table showing the results of carbon density parameter correction for land use types in active areas of coal mining subsidence according to the present invention (unit: t / hm2);

[0056] Figure 6 This is a table showing the results of carbon density parameter correction for land use types in the coal mining subsidence stabilization zone (unit: t / hm2);

[0057] Figure 7 This is a table showing the carbon density parameter correction results of land use types in the ecological restoration area of ​​coal mining subsidence in the present invention (unit: t / hm2);

[0058] Figure 8 This is a table showing the carbon density parameter correction results of land use types in the active collapse area after collapse repair according to the present invention (unit: t / hm2);

[0059] Figure 9 This is the carbon density parameter correction result table of land use types in the collapse stabilization area after collapse repair of the present invention (unit: t / hm2);

[0060] Figure 10 This is a table of carbon density parameter correction results for land use types in the ecological restoration area after collapse repair according to the present invention (unit: t / hm2). DETAILED DESCRIPTION

[0061] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in a variety of different configurations.

[0062] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but is merely intended to represent selected embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative work are within the scope of protection of the present invention.

[0063] Figure 1-10 A specific embodiment of the present invention is as follows: Figure 1 As shown, this embodiment is a method for estimating carbon storage in a coal mining subsidence area ecosystem based on the InVEST model, comprising:

[0064] S1. Divide the coal mining subsidence area according to land use type and determine the scope and area of ​​each land use type. Through high-precision land use classification, clarify the distribution and area of ​​different land types in the subsidence area, providing basic data support for subsequent carbon density parameter extraction and ecological restoration strategy formulation;

[0065] In this embodiment, step S1 specifically includes: collecting the "three surveys" data and land change survey data results of the coal mining subsidence area, and dividing the land use type i into cultivated land, forest land, garden land, grassland, water area, construction land and unused land, a total of 7 categories, that is, i∈{1,2,3,4,5,6,7}; determining the scope and area of ​​each land use type.

[0066] S2. Divide the coal mining subsidence area into multiple zones according to spatial status, and combine each zone and each land use type to form a land use grid table with a unique code;

[0067] In this embodiment, step S2 specifically comprises: using UAV LiDAR to collect high-precision digital elevation model (DEM) data and orthophotos of the coal mining subsidence area with a resolution of ≤5m, combining ground subsidence monitoring data to correct the topography of the coal mining subsidence area, and dividing the coal mining subsidence area space j into a non-subsidence area, an active subsidence area, a stable subsidence area, and an ecological restoration area, a total of four partitions, i.e., j∈{1,2,3,4}, and combining land use type i to form a land use raster table (i, j) with a unique code; using DEM and LiDAR data to divide the subsidence area into four spatial state partitions, and combining land use type to form a uniquely coded raster table to achieve spatiotemporal dynamic modeling; and the spatial heterogeneity modeling capability is strong, supporting dynamic monitoring and zoning management of the subsidence process, and providing a spatial basis for differentiated correction of carbon density parameters;

[0068] The land use grid table (i, j) data covers three time periods t, namely before collapse, during collapse and after collapse repair, that is, t∈{0,1,2}, then the land use grid table can be expressed as St(i,j) in time and space;

[0069] This example takes a coal mining subsidence area in Shandong as the research object and obtains land use type data for three time periods: before the collapse, during the collapse, and after the collapse repair. Based on the DEM data and ground monitoring data of each period, the coal mining subsidence area is divided into non-collapsed areas, active collapse areas, stable collapse areas, and ecological restoration areas, forming the land use grid table St(i, j) for each period.

[0070] S3. Obtain the initial carbon density parameters corresponding to each of the land use types, calculate the effect of surface subsidence on the carbon density parameters of each subdivision of the coal mining subsidence area, and perform differentiated corrections; dynamically correct the carbon density parameters based on surface subsidence to improve the local adaptability and dynamic response capability of carbon density estimation, and consider the impact of surface subsidence on carbon density, so as to make carbon storage estimation closer to reality and provide more accurate parameter support for ecological restoration and carbon sink management;

[0071] In this embodiment, step S3 is specifically as follows: obtaining the initial carbon density parameters corresponding to the land use type, including the aboveground biomass carbon density, by publicly published literature related to the area where the coal mining subsidence area is located or conducting on-site sampling and testing. C above , belowground biomass carbon density C below , soil carbon density C soil and dead organic matter carbon density C dead .

[0072] The carbon density values ​​corresponding to the above land use types are obtained by referring to the existing data in the published literature and combining with the actual situation of the coal mining subsidence area to obtain the carbon density parameters corresponding to each land use type. Figure 4 .

[0073] S4. Based on the InVEST model, the total carbon storage of coal mining subsidence areas at different collapse stages was calculated. The total carbon storage at different collapse stages was analyzed using ArcGIS to obtain the spatial distribution of carbon storage, carbon sequestration, and total carbon storage for each land use type, as well as statistical tables of contribution rates of each carbon pool. The temporal variation characteristics of carbon storage were comprehensively analyzed in combination with the carbon sequestration of each land use type at different collapse stages. Through the InVEST model and ArcGIS analysis, the spatiotemporal evolution analysis of carbon storage was realized, including carbon storage, carbon sequestration, and contribution rates of each carbon pool, which supported the comprehensive analysis of carbon storage variation characteristics. In addition, the InVEST model is advanced, with comprehensive analysis dimensions and strong visualization of results, providing a scientific basis for ecological restoration effectiveness evaluation and carbon sink management.

[0074] In this embodiment, step S4 is specifically as follows: embedding a dynamic correction algorithm for coal mining subsidence areas in the InVEST model carbon reserve module, calculating the surface subsidence based on DEM data, and performing differential correction on the carbon density parameters of each subdivision in the coal mining subsidence area. The corrected carbon density parameters are: C ' above 、 C ' below 、 C ' soil and C ' dead .

[0075] The spatiotemporal evolution results of total carbon reserves in coal mining subsidence areas were obtained in three time periods: before subsidence, during subsidence, and after subsidence repair.

[0076] The total carbon storage in different collapse stages of the coal mining subsidence area was calculated based on the InVEST model. The results were analyzed using ArcGIS to obtain the carbon storage and carbon sequestration of each land use type in different collapse stages. At the same time, the spatial distribution map of the total carbon storage in the coal mining subsidence area and the statistical table of the contribution rate of each carbon pool were output. Combined with the carbon sequestration of different land use types in different collapse stages, the temporal variation characteristics of carbon storage in each type of land in the coal mining subsidence area were comprehensively analyzed.

[0077] The S3, soil carbon density C ' soil The method of differential correction is:

[0078] The non-collapsed area (j=1) is not corrected;

[0079] The soil carbon density in the active collapse zone (j=2) was attenuated according to the original value. The attenuation coefficient was negatively correlated with the collapse depth. The formula is:

[0080] C' soil,t (i, 2) = C soil,0 (i, 2) × e -k×w

[0081] Where i is the i-th land use type; j = 2 is the area of ​​the active collapse zone; w is the amount of surface subsidence; k = 0.1~0.2 is the coefficient related to the amount of surface subsidence;

[0082] The soil carbon density in the collapsed stable zone (j=3) is linearly restored according to the stable years, and the formula is:

[0083] C' soil,t (i, 3) = C soil,0 (i, 3) × e -k×w +α×Δt1

[0084] Where i is the i-th land use type; j = 3 is the area of ​​the collapse stable zone; Δt1 is the stable period, and α = 0.05~0.15 is the coefficient related to the stable period;

[0085] The soil carbon density in the ecological restoration area (j=4) is restored by calculating the gain coefficient according to the ecological restoration years. The formula is:

[0086] C' soil,t (i, 4) = C soil,0 (i, 4)×(1+β×ln(Δt2+1))

[0087] Among them, i is the i-th land use type; j=4 is the area of ​​the ecological restoration zone; Δt2 is the restoration period, and β=0.1~0.3 is the coefficient related to the restoration period.

[0088] The method for the differential correction of aboveground biomass carbon density C'above in S3 is:

[0089] The non-collapsed area (j=1) is not corrected;

[0090] The collapse active area (j=2) and the collapse stable area (j=3) are corrected according to the principle that carbon loss increases by 5% for every 1° increase in slope because the collapse changes the terrain stability, resulting in damage to ground vegetation. The slope is calculated using DEM data, and the correction formula is:

[0091] C' above,t (i, j) = C above,0 (i, j) × (1-0.05 × s)

[0092] Where s is the slope.

[0093] The correction of aboveground biomass carbon density in the ecological restoration area (j=4) is related to multiple factors such as the vegetation restoration stage and subsequent management and maintenance. The correction formula is:

[0094] C' above,t (i, 4) = C above,0 (i, 4) × (1- e -2×Δt2 ) × r

[0095] Among them, Δt2 is the restoration period, and r is the management and protection measure coefficient (regular weeding r = 1.1, pest and disease control r = 1.05, no management r = 0.9).

[0096] Belowground biomass carbon density C ' below,t Differentiation correction based on S41 soil carbon density C ' soil,t Partition correction method.

[0097] Carbon density of dead organic matter in coal mining subsidence area C dead The method for performing differential correction is:

[0098] The non-collapsed area (j=1) is not corrected;

[0099] In the active collapse zone (j=2) and the stable collapse zone (j=3), the collapse disturbance accelerates the decomposition of litter, and the correction formula is:

[0100] C' dead,t (i, j) = C dead,0 (i, j) × e -0.02×w

[0101] Where i is the i-th land use type; j is the area of ​​the j-th collapse zone; w is the surface subsidence;

[0102] The carbon density of dead organic matter in the ecological restoration area (j=4) promotes organic matter accumulation through restoration measures, but frequent human interference will destroy the litter layer. The correction formula is:

[0103] C' dead,t (i, 4) = C dead,0 (i, 4)×(1+0.1×Δt2-0.05×Z)

[0104] Where i is the i-th land use type; j = 4 is the area of ​​the ecological restoration zone; Δt2 is the restoration period, and Z is the number of human disturbances during the restoration period.

[0105] In this embodiment, taking the cultivated land (i=1) in the coal mining subsidence (t=1) as an example, the soil carbon density is calculated according to the corresponding method. C ' soil,tThe correction results in each collapsed area are as follows:

[0106] Uncollapsed area: C' soil,2 (1, 1) = C soil,0 (1, 1) = 85.60;

[0107] Collapse active area: The average subsidence during this period is 1.5m, and k=0.1, then C' soil,2 (1, 2) = C soil,0 (1, 2) × e -k×w =85.60×e -0.1×1.5 =73.68;

[0108] Collapse stable zone: The average subsidence during this period is 1.8m, the stable period Δt1=1, and k=0.1 and α=0.15 are taken according to the stable state, then C' soil,t (1, 3) = C soil,0 (1, 3) × e -k×w +α×Δt1=85.60×e -0.1×1.8 +0.15×1=71.65;

[0109] Ecological restoration area: restoration period Δt2=2, according to the restoration effect, take β=0.1, then C' soil,t (1, 4) = C soil,0 (1, 4)×(1+β×ln(Δt2+1))=85.60×(1+0.1×ln(2+1))=95.00.

[0110] Similarly, the modified results of different carbon density parameters of each land use type i in each collapse zone j in each time period t are calculated according to the above method. Figures 5-10 .

[0111] The InVEST model-based carbon storage estimation method for coal mining subsidence area ecosystems in this embodiment is suitable for the accounting of carbon sink trading volume in mining area ecological restoration projects, and supports the allocation of carbon emission quotas and carbon neutrality target assessment.

[0112] In this embodiment, the method for estimating carbon reserves in ecosystems in coal mining subsidence areas based on the InVEST model can also be coupled with the MCE-CA model to realize the prediction of carbon reserve evolution. Based on multi-criteria evaluation (MCE) and cellular automation (CA), the subsidence expansion and land use changes in the next 10 years are simulated to dynamically update the carbon reserve estimation results.

[0113] The InVEST model-based method for estimating carbon reserves in coal mining subsidence ecosystems in this embodiment is also applicable to calculating carbon sink trading volumes for mining area ecological restoration projects, supporting the allocation of carbon emission quotas and the assessment of carbon neutrality targets. Furthermore, it can be deployed on a cloud-based GIS platform, allowing users to upload mining area data online, automatically calling the InVEST model to generate carbon reserve reports. It also supports AR visualization, overlaying carbon reserve distribution with real-life images of the subsidence area via mobile devices.

[0114] In summary, the technical system constructed by the InVEST model-based method for estimating ecosystem carbon reserves in coal mining subsidence areas in this embodiment enables systematic, dynamic, and refined carbon stock estimation and ecological restoration assessment. This technical system is not only applicable to coal mining subsidence areas but can also be extended to ecological restoration and carbon accounting research in other types of mines or land degradation areas, possessing important practical application value and scientific significance.

[0115] like Figure 3 As shown, a system for estimating carbon storage in ecosystems of coal mining subsidence areas using an InVEST model is provided, comprising:

[0116] Land use classification module: This module divides the coal mining subsidence area into different land use types and determines the scope and area of ​​each land use type. This module provides basic land attribute data for the subsequent extraction of carbon density parameters and carbon storage calculations, enables land use classification and spatial statistics, and helps identify the differences in ecological functions of different land types in the subsidence area, providing a classification basis for carbon storage assessment.

[0117] Spatial Zoning Coding Module: This module divides the coal mining subsidence area into multiple zones based on spatial status. Each zone and each land use type are combined to form a land use grid table with a unique code. By constructing a data structure with integrated spatial attributes, it facilitates carbon density correction and spatial analysis, enabling spatial refinement and coding management of subsidence areas. This module also improves data operability and spatial resolution, laying the foundation for spatial distribution analysis of carbon reserves.

[0118] Carbon density parameter correction module: obtains the initial carbon density parameters corresponding to each land use type, calculates the effect of surface subsidence on the carbon density parameters of each sub-area in the coal mining subsidence area, and makes differentiated corrections. By correcting the impact of subsidence on carbon density, the accuracy of carbon reserve assessment can be improved. It can also achieve dynamic correction of carbon density parameters and provide more realistic carbon density data for subsequent carbon reserve calculations, reflecting the complexity of ecological changes in the subsidence area.

[0119] Carbon reserve assessment and analysis module: Based on the corrected carbon density parameters, the InVEST model is used to calculate the total carbon reserves in different collapse stages of the coal mining subsidence area. ArcGIS is used to analyze the total carbon reserves in different collapse stages to obtain the carbon reserves, carbon sequestration, spatial distribution of total carbon reserves and carbon pool contribution rate statistics of each land use type. The temporal change characteristics of carbon reserves are comprehensively analyzed in combination with the carbon sequestration of each land use type in different collapse stages. By evaluating the spatiotemporal distribution and change trend of carbon reserves in the collapse area, quantitative assessment and spatiotemporal analysis of carbon reserves can be achieved, and a scientific basis can be provided for the ecological restoration and carbon sink potential assessment of the collapse area, which will help achieve sustainable development and carbon neutrality goals.

[0120] The MCE-CA model is used to predict the evolution of carbon reserves in the ecosystem carbon stock estimation method of coal mining subsidence areas based on the InVEST model, and to simulate the subsidence expansion and land use changes in the next 10 years based on multi-criteria evaluation (MCE) and cellular automation (CA), and dynamically update the carbon stock estimation results.

[0121] Memory, wherein the MCE-CA model is stored in the memory and configured to be executed by the one or more processors, and the MCE-CA model is used to execute instructions of any method in the method for estimating carbon reserves in coal mining subsidence area ecosystems based on the InVEST model in Example 1.

[0122] The cloud-based GIS platform allows users to upload mining area data online and automatically calls the InVEST model to generate a carbon reserve report. It also supports AR visualization, overlaying carbon reserve distribution with real-life images of the subsidence area through mobile devices.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention and are not limiting. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in this field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. A method for estimating carbon reserves in ecosystems of coal mining subsidence areas, characterized in that: The following steps are involved: S1. Divide the coal mining subsidence area according to land use type and determine the scope and area of ​​each land use type; S2. Divide the coal mining subsidence area into multiple zones according to spatial status, and combine each zone and each land use type to form a land use grid table with a unique code; The spatial states include: non-collapsed area, active collapse area, stable collapse area and ecological restoration area; S3. Obtaining the initial carbon density parameter corresponding to each land use type, calculating the carbon density parameter of each subdivision of the coal mining subsidence area based on the surface subsidence, and performing differential correction; In S3, the initial carbon density parameters include: aboveground biomass carbon density C above , belowground biomass carbon density C below , soil carbon density C soil and dead organic matter carbon density C dead ; Soil carbon density C soil The differential correction method is as follows: the non-collapsed area is not corrected; The soil carbon density in the active collapse area is attenuated according to the original value. The attenuation coefficient is negatively correlated with the collapse depth. The formula is: C’ soil,t (i,2)= C soil,0 (i,2)×e -k×w Where i is the i-th land use type; j = 2 is the area of ​​the active collapse zone; w is the surface subsidence, and k = 0.1~0.2 is the coefficient related to the surface subsidence; The soil carbon density in the collapsed stable area is linearly restored according to the stable years, and the formula is: C’ soil,t (i,3)=C soil,0 (i,3)×e -k×w +α×Δt1 Where i is the i-th land use type; j = 3 is the area of ​​the collapse stable zone; Δt1 is the stable period, and α = 0.05~0.15 is the coefficient related to the stable period; The soil carbon density in the ecological restoration area is restored by calculating the gain coefficient according to the ecological restoration years. The formula is: C’ soil,t (i,4)=C soil,0 (i,4)×(1+β×ln(Δt2+1)) Where i is the i-th land use type; j = 4 is the area of ​​the ecological restoration zone; Δt2 is the restoration period, and β = 0.1-0.3 is the coefficient related to the restoration period; The carbon density of aboveground biomass in each zone of coal mining subsidence area C above The method for performing differential correction is: The non-collapsed area is not corrected; The collapse active area and the collapse stable area have changed the stability of the terrain due to collapse, which has caused damage to the ground vegetation. Therefore, the carbon loss is corrected by 5% for every 1° increase in slope. The slope is calculated using DEM data, and the correction formula is: C’ above,t (i,j)=C above,0 (i,j)×(1-0.05×s) Where i is the i-th land use type; j is the area of ​​the j-th collapse zone; s is the slope; The correction of aboveground biomass carbon density in the ecological restoration area is related to multiple factors in the vegetation restoration stage and subsequent management and maintenance. The correction formula is: C’ above,t (i,4)=C above,0 (i,4)×(1-e -2×Δt2 )×r Where i is the i-th land use type; j = 4 is the area of ​​the ecological restoration zone; Δt2 is the restoration period, and r is the management and protection measure coefficient; Carbon density of dead organic matter in coal mining subsidence area C dead The method for performing differential correction is: The non-collapsed area is not corrected; The collapse active zone and the collapse stable zone accelerate the decomposition of litter due to collapse disturbance, and the correction formula is: C’ dead,t (i,j)=C dead,0 (i,j)×e -0.02×w Where i is the i-th land use type; j is the area of ​​the j-th collapse zone; w is the surface subsidence; The carbon density of dead organic matter in the ecological restoration area promotes organic matter accumulation through restoration measures, but frequent human interference will destroy the litter layer. The correction formula is: C’ dead,t (i,4)=C dead,0 (i,4)×(1+0.1×Δt2-0.05×Z) Where i is the i-th land use type; j = 4 is the area of ​​the ecological restoration zone; Δt2 is the restoration period, and Z is the number of human disturbances during the restoration period; S4. Based on the corrected carbon density parameters, the InVEST model was used to calculate the total carbon storage in different collapse stages of the coal mining subsidence area. ArcGIS was used to analyze the total carbon storage in different collapse stages, and the carbon storage, carbon sequestration, spatial distribution of total carbon storage and contribution rate of each carbon pool of each land use type were obtained. The temporal variation characteristics of carbon storage were comprehensively analyzed in combination with the carbon sequestration of each land use type in different collapse stages.

2. The method for estimating carbon reserves in a coal mining subsidence area ecosystem according to claim 1, characterized in that: In S1, the land use types include: cultivated land, forest land, garden land, grassland, water area, construction land and unused land.

3. The method for estimating carbon reserves in a coal mining subsidence area ecosystem according to claim 1, characterized in that: In S2, the method for obtaining the spatial state of the coal mining subsidence area is: using drone LiDAR to collect high-precision digital elevation model data and orthophotos of the coal mining subsidence area with a resolution of ≤5m, and combining ground subsidence monitoring data to correct the terrain undulation of the coal mining subsidence area.

4. The method for estimating carbon reserves in a coal mining subsidence area ecosystem according to claim 1, characterized in that: In said S3, the method for obtaining the initial carbon density parameter corresponding to each said land use type is: through publicly published literature related to the area where the coal mining subsidence area is located or through on-site sampling and testing.

5. The method for estimating carbon reserves in a coal mining subsidence area ecosystem according to claim 1, characterized in that: S4, based on the InVEST model, calculates the total carbon reserves of the coal mining subsidence area at different subsidence stages, specifically: Total carbon storage in coal mining subsidence area at time period t C total,t The calculation formula is: C total,t =Σ[ S t (i,j)×( C ’ above,t (i,j)+ C ’ below,t (i,j)+ C ’ soil,t (i,j)+ C ’ dead,t (i,j))] in, S t (i, j) is the area of ​​the jth subsidence zone of the i-th land use in time period t, C above is the aboveground biomass carbon density; C below is the belowground biomass carbon density; C soil is soil carbon density; C dead is the carbon density of dead organic matter.

6. A system for estimating carbon reserves in a coal mining subsidence area ecosystem, using the method for estimating carbon reserves in a coal mining subsidence area ecosystem according to any one of claims 1 to 5, characterized in that: include: The land use type classification module is used to classify the coal mining subsidence area according to the land use type and determine the scope and area of ​​each land use type; The spatial partition coding module is used to divide the coal mining subsidence area into multiple partitions according to the spatial state, and combine each partition and each land use type to form a land use grid table with a unique code; The spatial states include: non-collapsed area, active collapse area, stable collapse area and ecological restoration area; A carbon density parameter correction module is used to obtain the initial carbon density parameter corresponding to each land use type, calculate the carbon density parameter of each subdivision of the coal mining subsidence area based on the surface subsidence, and perform differentiated corrections; The carbon reserve assessment and analysis module is used to calculate the total carbon reserve at different collapse stages in coal mining subsidence areas using the InVEST model based on the corrected carbon density parameters. The total carbon reserve at different collapse stages is analyzed using ArcGIS to obtain statistical tables of carbon reserve, carbon sequestration, spatial distribution of total carbon reserve, and contribution rate of each carbon pool for each land use type. The temporal variation characteristics of carbon reserve are comprehensively analyzed in combination with the carbon sequestration of each land use type at different collapse stages.

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