Coupling method based on "soil erosion process-landscape pattern" comprehensive risk

Abstract

The application discloses a coupling method based on a "soil erosion process-landscape pattern" comprehensive risk, which comprises the following steps: step 1, calculation of a soil erosion equation; step 2, calculation of a soil erosion process ecological risk index; step 3, calculation of a landscape pattern risk index; and step 4, coupling of the "soil erosion process-landscape pattern" to establish a comprehensive landscape ecological risk index. The application utilizes both the risk occurrence probability and the event probability to solve the probability, and utilizes a probability-loss model to calculate the comprehensive landscape ecological risk index of both. The coupling method can reflect the commonness and individuality between things in essence, effectively solves the problem that the coupling of a landscape dynamic process and a static mosaic pattern is too simple, and truly reflects the "ecological process-landscape pattern" comprehensive landscape ecological risk, thereby providing an effective way for the coupling of the landscape dynamic process and the static mosaic pattern.

Description

Technical Field

[0001] This invention belongs to the field of landscape ecology and relates to a landscape ecological risk assessment method, specifically a coupling method based on the comprehensive risk of "soil erosion process-landscape pattern". Background Technology

[0002] Ecological risk assessment began in the United States in the late 1970s and early 1980s. With the advancements in ecological risk assessment research over the past few decades, significant progress has been made in terms of content, methods, and scale. Currently, common landscape ecological risk assessments primarily focus on two aspects: evaluating the ecological risk effects of deviations of landscape mosaics from their optimal patterns, and conducting receptor analysis and exposure hazard assessment based on the identification of risk sources. The former is ecological risk assessment induced by land use / cover change. It mainly involves dividing land use into multiple risk assessment units, multiplying the area of ​​each assessment unit by the ratio of the area of ​​each land type within that unit, and then by the risk value of that unit. The latter takes a micro-level perspective, exploring the ecological risks posed by risk sources and discussing methods and models for landscape ecological risk assessment. For example, Ayre et al. used a Bayesian network model to conduct an ecological risk assessment of forest landscapes in Oregon, USA. Bhuiyan et al. studied the ecological risks posed by heavy metal pollution in agricultural soils in the Dhaka region. Proshad et al. studied the pollution levels and distribution of heavy metals in the Rupsa River sediments in Bangladesh and their ecological and health risks.

[0003] Landscape ecological risk refers to the adverse consequences that may arise from the interaction between landscape patterns and ecological processes under the influence of natural or anthropogenic factors. In recent years, ecological research based on landscape patterns has been able to analyze the interrelationships between ecological dynamic processes and spatial patterns, enabling comprehensive characterization and spatial visualization of multiple risks. This is extremely important for the maintenance and protection of regional ecological security and has become a hot topic of concern for scholars both domestically and internationally. Methods involving the integration of "process-pattern" in landscape risk include: Liu Shiliang et al., using the Red River Basin in Yunnan as an example, using the soil erosion index to characterize the impact of risk sources on landscape processes, and establishing a comprehensive landscape ecological risk index based on landscape patterns and ecological processes; Zheng Xuehui et al., using meteorological, vegetation, DEM, soil, and land use data to construct a comprehensive evaluation model of soil erosion sensitivity and landscape ecological risk; and Hu Hebing et al., starting from the regional ecosystem structure, constructing a comprehensive ecological risk index based on landscape structure, and using ArcGIS spatial analysis functions to reveal the spatiotemporal variation characteristics of ecological risk in the Jiuxiang River Basin, as well as the impact of urbanization on the basin's ecological risk.

[0004] Existing literature suggests that most scholars assess landscape ecological risk primarily by evaluating a single ecological process or landscape pattern, with few combining both for a comprehensive evaluation. Current research on soil erosion ecological process risk indices mainly uses soil erosion sensitivity and soil erosion equations, but these methods are overly simplistic. Regarding the coupling of soil erosion ecological processes and landscape patterns, previous studies have merely multiplied and merged the two risks, explaining only their commonalities while neglecting their individual characteristics, thus failing to reflect the risk index resulting from their mutual influence. Summary of the Invention

[0005] This invention utilizes the soil erosion process risk index and the landscape pattern risk index. Addressing the shortcomings of previous studies that oversimplified the integration of ecological process and landscape pattern risks, failing to reflect the true risk values ​​of the study area and the dynamic processes and static mosaic patterns of the landscape, this invention proposes a novel coupling method based on the comprehensive risk of soil erosion process and landscape pattern. This method can more specifically and objectively reflect the comprehensive risk of "process-pattern," providing an effective approach for calculating the ecological process risk of soil erosion and optimizing the coupling of dynamic processes and static mosaic patterns of the landscape.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A coupled approach based on the integrated risk of "soil erosion process-landscape pattern" includes the following steps:

[0008] Step 1: Calculation of the soil and water loss equation: The amount of soil and water loss is calculated by using the soil and water loss equation based on the rainfall erosivity factor, soil erodibility factor, slope and slope length factor, vegetation cover factor, and soil and water conservation measures factor.

[0009] Step 2: Calculation of the ecological risk index for the soil erosion process: The ecological risk index for the soil erosion process is calculated using the visualization results of soil erosion. The specific steps are as follows:

[0010] Step 2.1: Divide the study area into equal risk cell grids and convert them into vector data using land use classification data;

[0011] Step 2.2: Use a grid to cut the vector-form study area into equal-sized risk units, and use these units to statistically analyze the soil and water loss risk values ​​under different land types.

[0012] Step 2.3: Multiply the ratio of the area of ​​each land type in different risk cell grids to the area of ​​the cell grid by the product of the average soil and water loss of the land type in the risk unit and the area of ​​each land type, and then normalize it to obtain the ecological risk index of soil and water loss process.

[0013] Step 2.4: Standardize the calculation results from Step 2.3;

[0014] Step 3: Calculation of landscape pattern risk index: Construct a landscape disturbance index using three indicators: landscape fragmentation, landscape separation, and landscape fractal dimension. Combine this with the landscape vulnerability index to calculate the landscape loss index. Finally, calculate the landscape pattern risk index using the landscape loss index and the area ratio of landscape types.

[0015] Step 4: Couple "soil erosion process - landscape pattern" to establish a comprehensive landscape ecological risk index: Using the constructed landscape ecological risk value based on landscape pattern and soil erosion process, and based on the calculation of event probability, couple the soil erosion process risk index and the landscape pattern risk index to establish a comprehensive landscape ecological risk assessment model.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] (1) Previous calculations of the ecological risk of soil erosion mainly involved dividing the study area into risk assessment units of the same scale and using a loss index instead of a risk index. This method is too crude and simplistic in calculating the index. This invention improves the calculation method for the ecological risk of soil erosion by changing the original method of averaging the soil erosion risk of each cell to averaging the soil erosion risk values ​​of the corresponding land types within each cell. Finally, this average is multiplied by a weighted value representing the ratio of the area of ​​the corresponding land type within each cell to the total area of ​​the cell, and a weighted sum is obtained to obtain the soil erosion hazard value. The ecological risk index of the soil erosion process is then calculated using a probability-loss model. This improved method increases the accuracy of the soil erosion risk index within each cell grid and more accurately reflects the soil erosion risk of the study area.

[0018] (2) Addressing the oversimplification of previous studies on the coupling of landscape dynamic processes and static mosaic patterns. Previous studies treated soil erosion as a single risk source and landscape pattern loss as the ultimate outcome, without establishing a risk index for their mutual influence. This reduced the overall risk value to some extent, hindering risk management and emergency response. To address this, this invention improves the coupling method for landscape dynamic processes and static mosaic patterns by treating both processes and patterns as risk sources and calculating their respective hazard indices. This is because patterns and processes are mutually influential yet independent in the real world. Therefore, this invention uses event probabilities to calculate the probability of risk occurrence for both and employs a probability-loss model to calculate the comprehensive landscape ecological risk index. This coupling method more accurately reflects the commonalities and individual characteristics between things, effectively solving the oversimplification problem of coupling landscape dynamic processes and static mosaic patterns, truly reflecting the comprehensive landscape ecological risk of "ecological process-landscape pattern," and providing an effective approach for coupling landscape dynamic processes and static mosaic patterns. Attached Figure Description

[0019] Figure 1 A flowchart of a coupling method for integrated landscape ecological risk based on "soil erosion process-landscape pattern";

[0020] Figure 2 For comparison of the improved and unimproved results;

[0021] Figure 3 To improve and not improve the distribution of risk indices. Detailed Implementation

[0022] The technical solution of the present invention will be further described below with reference to the accompanying drawings, but it is not limited thereto. Any modifications or equivalent substitutions to the technical solution of the present invention that do not depart from the spirit and scope of the technical solution of the present invention should be covered within the protection scope of the present invention.

[0023] This invention provides a coupling method for comprehensive landscape ecological risk based on "soil erosion process-landscape pattern". It establishes an improved soil erosion ecological process risk index based on the soil erosion equation (USLE) using rainfall erosivity factor R, soil erodibility factor K, slope and length factor LS, vegetation cover factor C, and soil and water conservation measure factor P. Furthermore, it calculates the landscape pattern risk index by establishing a landscape loss degree using a landscape disturbance index and a landscape vulnerability index. Finally, it couples the improved soil erosion process risk index and landscape pattern risk index with an event probability calculation formula to achieve the extraction of a comprehensive landscape ecological risk index. Figure 1 As shown, the specific steps include:

[0024] Step 1: Calculation of the soil erosion equation: The amount of soil loss is calculated using the soil erosion equation (USLE) based on the rainfall erosivity factor R, soil erodibility factor K, slope length factor LS, vegetation cover factor C, and soil and water conservation measure factor P.

[0025] usle=R×K×L×S×C×P

[0026] 1) Soil erodibility K: refers to the ease with which soil particles are separated and transported by water. It is mainly related to soil texture, organic matter content, soil structure, permeability, and other soil physicochemical properties. The calculation formula is as follows:

[0027] K = (-0.01383 + 0.51575K) EPIC )×0.1317

[0028]

[0029] In the formula, K is the corrected soil erodibility factor; K EPIC The values ​​are: soil erodibility factors before correction; SAN is sand content (%); SIL is silt content (%); CLA is clay content (%); C is organic carbon content (%).

[0030] 2) Slope Length Factor (LS): Topographic relief significantly impacts the degree of soil erosion. The slope length factor (LS) is a crucial indicator for measuring topographic relief. Incorporating this factor into the soil erosion risk calculation process allows for a more accurate understanding of the actual soil erosion risk in the study area. This invention references the topographic factor calculation methods used by relevant scholars in soil erosion studies of similar areas. The formula for calculating the slope length factor (LS) is as follows:

[0031]

[0032]

[0033] In the formula, L is the slope length factor; S is the slope gradient factor; γ is the slope length, the value of which is the basic spatial granularity of the raster data. This invention uses DEM data with a resolution of 30m, so γ = 25; m is a dimensionless constant. When the slope percentage is greater than 5, m equals 0.5; when the slope percentage is between 3 and 5, m equals 0.4; when the slope percentage is between 1 and 3, m equals 0.3; when the slope percentage is less than 1, m equals 0.2; α represents the slope.

[0034] 3) Soil and water conservation measures factor P: This factor represents the impact of differences in the management and protection levels of different landscape types on the degree of soil erosion. It is typically calculated as the ratio of the total soil erosion after implementing protection measures to the total soil erosion when planting along slopes. The value range is [0,1], where 1 represents areas with soil and water conservation measures and 0 represents areas with no risk of soil erosion. The soil and water conservation measures factor P is assigned the following values: Irrigated farmland has a lower risk of soil erosion, so the P value is 0.15; dry land, often terraced, has a relatively higher risk of soil erosion, so the P value is 0.5; water bodies and urban land have a value of 0; other land use types have a value of 0.5.

[0035] 4) Vegetation Cover Factor C: The vegetation cover factor is calculated based on the vegetation cover index f, and the C value is calculated using the vegetation cover management formula.

[0036]

[0037]

[0038] In the formula, f is the vegetation cover; NDVI is the vegetation cover; NDVI max The maximum value of vegetation cover in the study area; NDVI min This represents the minimum value of vegetation coverage.

[0039] 5) Rainfall erosivity factor R: The impact of precipitation on soil erosion is reflected by the rainfall erosivity factor, which indicates the magnitude of the dynamics of soil dispersion and transport caused by rainfall, i.e., the potential for rainfall to cause soil erosion. Its calculation formula is:

[0040]

[0041] In the formula, P d This represents the average annual rainfall over many years.

[0042] Step 2: Calculation of the ecological risk index for the soil erosion process: The ecological risk index for the soil erosion process is calculated using the visualization results of soil erosion. The specific steps are as follows:

[0043] Step 2.1: Divide the study area into equal risk cell grids and convert them into vector data using land use classification data;

[0044] Step 2.2: Use a grid to crop the vector study area into equal-sized risk units, and use these units to statistically analyze the ecological risk values ​​of soil and water loss processes under different land types.

[0045] Step 2.3: Multiply the ratio of the area of ​​each land type within different risk cell grids to the area of ​​the cell grid by the product of the average soil and water loss of each land type in the risk unit and the area of ​​each land type, and then normalize the product to obtain the soil and water loss process hazard index. The formula is as follows:

[0046]

[0047] In the formula, UU k This represents the risk level of soil erosion in the k-th risk area without standardized treatment. A represents the average degree of soil erosion across different land types within the k-th risk zone; ki Let A be the area of ​​landscape type i within the k-th risk zone; k denoted as the total area of ​​the kth risk zone; k is the risk zone number; i is the local land cover number; and N is the number of patch component types.

[0048] Step 2.4: Standardize the calculation results from Step 2.3 using the following formula:

[0049] UU′ k =[(UU k -min(UU)) / (max(UU)-min(UU))]×(new max(uu′) -new min(uu′) )+new min(uu′)

[0050] In the formula, UU′ k UU represents the risk level of soil erosion after standardized treatment in the k-th risk area; k This represents the unstandardized soil erosion hazard value of the k-th risk area; min(UU) and max(UU) represent the minimum and maximum values ​​of the original soil erosion hazard values ​​at a single scale, respectively; new max(uu′) and new min(uu′) These represent the maximum and minimum values ​​of the data standardization mapping interval, respectively; the standardized soil erosion values ​​are all within the range of [0,1].

[0051] Step 2.5: Use the normalization formula from Step 2.4 to... With A ki After normalizing the product of the two values, the soil erosion loss index is obtained. Then, the ecological risk index of the soil erosion process is obtained by multiplying the soil erosion risk index by the soil erosion loss index. The expression is as follows:

[0052] TT k =SS k UU′ k

[0053] In the formula, TT k SS represents the ecological risk index of soil erosion process in the k-th risk area. k This represents the soil erosion loss index of the kth risk area.

[0054] Step 3, Calculation of Landscape Pattern Risk Index: Using landscape fragmentation (C i Landscape separation (N) i Landscape fractal dimension (D) i The landscape disturbance index (E) is constructed using three indicators. i ), and combined with the landscape vulnerability index (F i ) Calculate the landscape loss index (R) k Finally, the landscape loss index and landscape pattern hazard (GG) were used. k Calculate the landscape pattern risk index (ERI) k ).

[0055] 1) Landscape Disturbance Index (E) i Landscape disturbance index (E): Indicates the degree of external disturbance affecting different types of landscapes. i ) by landscape fragmentation (C i Landscape separation (N) i Landscape fractal dimension (D) i The calculation yields the following expression:

[0056] E i =aC i +bN i +cD i

[0057] In the formula, E i C represents the landscape disturbance index for landscape type i. i Let N be the landscape fragmentation index for landscape type i. i D is the landscape separation index for landscape type i. i Let be the landscape fractal dimension of landscape type i, and a, b, and c be the weights of the corresponding landscape indices.

[0058] Landscape fragmentation index (C i The expression is:

[0059]

[0060] In the formula, n i Let A be the number of patches in landscape i. i Let i be the total area of ​​landscape i.

[0061] Landscape Separation Index (N) i The expression is:

[0062]

[0063] In the formula, A represents the total area of ​​the landscape.

[0064] Landscape fractal dimension (D) i The expression is:

[0065] D i =2ln(P) i / 4) / ln(A i )

[0066] In the formula, P i Let D be the perimeter of landscape i. i The higher the value, the more complex the patch shape. i The theoretical range of the value is 1.0 to 2.0, where 1.0 represents the simplest square patch and 2.0 represents the most complex patch in terms of perimeter under the same area.

[0067] 2) Landscape vulnerability index (F i Landscape vulnerability represents the degree of fragility of various landscape types after exposure to external disturbances. Based on the actual conditions of the study area, an expert scoring method was used to classify the vulnerability of unused land, water bodies, cultivated land, grassland, forest land, and construction land in the study area into six levels from high to low. After normalization, the vulnerability index F for each landscape type was obtained. i .

[0068] 3) Landscape Loss Index (R) k Landscape loss degree represents the extent to which a landscape loses its resistance to external disturbances. The calculation formula is as follows:

[0069]

[0070] In the formula, R k E represents the landscape loss index within the k-th risk zone. ki F represents the disturbance degree of landscape type i within the k-th risk zone; ki Let represent the vulnerability of landscape type i within the k-th risk zone.

[0071] 4) Landscape pattern hazard index (GG) k The landscape pattern hazard index characterizes the probability and intensity of risk sources, and its calculation formula is as follows:

[0072]

[0073] In the formula, GG k A represents the landscape pattern hazard index within the k-th risk zone; ki Let A be the area of ​​landscape type i within the k-th risk zone; k Let be the total area of ​​the kth risk zone.

[0074] 5) Landscape Pattern Risk Index (ERI) k ):

[0075] ERI k =R k GG k

[0076] In the formula, ERI k Let be the landscape ecological risk index of the k-th risky community.

[0077] Step 4: Establish a comprehensive landscape ecological risk index by coupling "soil erosion process - landscape pattern": Using the constructed landscape ecological risk value based on landscape pattern and soil erosion process, and based on the event probability calculation, couple the soil erosion process risk index and the landscape pattern risk index to establish a comprehensive landscape ecological risk assessment model, as shown in the following formula:

[0078]

[0079] In the formula, ERI′ k This represents the comprehensive landscape ecological risk value based on landscape pattern and soil erosion process within the k-th risk zone.

[0080] Figure 2 and Figure 3 This is a diagram showing the results of the improved method of coupling the ecological process risk index of soil erosion with the landscape pattern risk index, based on the present invention. Figure 2 In the diagram, a, b, and c represent landscape pattern risk, soil erosion ecological process risk, and the comprehensive landscape ecological risk of "soil erosion process-landscape pattern," respectively. d, e, and f represent improved landscape pattern risk, improved soil erosion ecological process risk, and the improved comprehensive landscape ecological risk of "soil erosion process-landscape pattern," respectively. Figure 2 The distribution of various ecological risk indices shows that the distributions of the unimproved soil erosion ecological process risk (b) and the improved soil erosion ecological process risk (e) are roughly the same, but there are slight differences in details between b and e. The high-risk areas in b have a larger map patch extension range than those in e. The map shows that the distributions of the soil erosion ecological process risk and the improved soil erosion ecological process risk are roughly similar. Compared to the unimproved soil erosion ecological process risk, the improved soil erosion ecological process risk distribution is more continuous, without any abrupt increases or decreases. This phenomenon is related to the fact that before the improvement, the average soil erosion value was calculated using risk areas as units, resulting in a large map extension and relatively low accuracy of the patch values. After the improvement, the average soil erosion value was calculated using each land type within each risk area as a unit, making the image patches and their extensions smaller than before the improvement. It did not use a single average value to replace the average value of a large area, so the patch area is smaller, which can more finely represent the distribution of the risk index, and the accuracy of the soil erosion ecological process risk is improved compared to before the improvement.

[0081] Figure 3 The distribution results of the risk indices show that the improved integrated landscape ecological risk of the coupled "soil erosion process-landscape pattern" is higher than that of the unimproved integrated landscape ecological risk. The overall risk index distribution of the unimproved integrated landscape ecological risk is smaller compared to the risk index distribution of individual landscape patterns and soil erosion ecological processes. The reason for this is... Figure 2 The product of a and b, i.e., using a single soil erosion process as the risk source, transforms areas that were originally high-risk zones in a and b into medium- or low-risk zones. Therefore, the unmodified coupling method underestimates the risk indices of both, preventing timely measures to reduce risk and, to some extent, increasing losses. Furthermore, the unmodified coupling formula essentially uses soil erosion as a single risk source to replace the probability of pattern-process risk occurrence; this method is somewhat one-sided and lacks practical significance. In the real world, processes influence patterns, and patterns also influence processes; therefore, a risk index under the combined influence of patterns and processes should be established. Addressing the commonalities and unique characteristics between soil erosion ecological processes and landscape patterns, this invention applies the calculation method of event probabilities to the coupling method, making it more realistically reflect the comprehensive landscape ecological risk of the study area.

Claims

1. A coupled method based on the integrated risk of "soil erosion process-landscape pattern", characterized in that... The method includes the following steps: Step 1, Calculation of the soil erosion equation: based on rainfall erosivity factor Soil erodibility factors Slope and slope length factors Vegetation coverage factor and soil and water conservation measures factors Using the soil erosion equation Calculate soil erosion; Step 2, Calculation of the ecological risk index of the soil and water loss process: The ecological risk index of the soil and water loss process is calculated using the visualization results of soil and water loss. Step 3: Calculation of landscape pattern risk index: Construct a landscape disturbance index using three indicators: landscape fragmentation, landscape separation, and landscape fractal dimension. Combine this with the landscape vulnerability index to calculate the landscape loss index. Finally, calculate the landscape pattern risk index using the landscape loss index and the area ratio of landscape types. Step 4: Establish a comprehensive landscape ecological risk index by coupling "soil erosion process - landscape pattern": Using the constructed landscape ecological risk value based on landscape pattern and soil erosion process, and based on the event probability calculation, couple the soil erosion process risk index and the landscape pattern risk index to establish a comprehensive landscape ecological risk assessment model. The formula for the comprehensive landscape ecological risk assessment model is as follows: In the formula, Representing the Comprehensive landscape ecological risk value based on landscape pattern and soil erosion process within each risk area; Indicates the first Risk values ​​of soil erosion process after standardized treatment of risk areas; For the first Landscape type within risky communities The area; For the first The total area of ​​each high-risk community; For the first Landscape loss index within each high-risk community; Indicates the first The soil erosion loss index of each high-risk community; Number the high-risk communities; Number each region by category; This represents the number of plaque component types.

2. The coupling method based on the comprehensive risk of "soil erosion process-landscape pattern" as described in claim 1, characterized in that... In step 1, soil erodibility The calculation formula is as follows: In the formula, The corrected soil erodibility factor; Soil erodibility factors before correction; This refers to the sand particle content; The content of silt; Clay content; The content of organic carbon; Slope length factor The calculation formula is as follows: In the formula, Slope length factor; Slope factor; The slope length; It is a dimensionless constant; when the slope percentage is greater than 5, It equals 0.5; when the slope percentage is between 3 and 5, It equals 0.4; When the slope percentage is between 1 and 3 Equals 0.3; when the slope percentage is less than 1, It equals 0.2; Represents slope; vegetation cover factor The calculation formula is as follows: In the formula, Vegetation coverage; Vegetation coverage; This represents the maximum vegetation cover in the study area; This represents the minimum value of vegetation cover. Rainfall erosivity factor The calculation formula is as follows: In the formula, This refers to the average annual rainfall over many years. Soil and water loss equation as follows: 。 3. The coupling method based on the comprehensive risk of "soil erosion process-landscape pattern" as described in claim 1, characterized in that... The specific steps of step 2 are as follows: Step 2.1: Divide the study area into equal risk cell grids and convert them into vector data using land use classification data; Step 2.2: Use a grid to cut the vector-form study area into equal-sized risk units, and use these units to statistically analyze the soil and water loss risk values ​​under different land types. Step 2.3: Multiply the ratio of the area of ​​each land type in different risk cell grids to the area of ​​the cell grid by the product of the average soil and water loss of the land type in the risk unit and the area of ​​each land type, and then normalize it to obtain the ecological risk index of soil and water loss process. Step 2.4: Standardize the calculation results from Step 2.3; Step 2.5: Use the normalization formula from Step 2.4 to... and The product of the two is normalized to obtain the soil erosion loss index, which is then multiplied by the soil erosion risk index to obtain the soil erosion loss index.

4. The coupling method based on the comprehensive risk of "soil erosion process-landscape pattern" according to claim 1, characterized in that... In step 2.3, the formula for calculating the ecological risk index of the soil erosion process is as follows: In the formula, Indicates the first Risk values ​​of soil erosion processes in individual high-risk communities that have not undergone standardized treatment; Indicates the first Average levels of soil erosion in different land types within each high-risk area; For the first Landscape type within risky communities The area; For the first The total area of ​​each high-risk community; Number the high-risk communities; Number each region by category; This represents the number of plaque component types.

5. The coupling method based on the comprehensive risk of "soil erosion process-landscape pattern" according to claim 1, characterized in that... In step 2.4, the standardization formula is as follows: In the formula, Indicates the first Risk values ​​of soil erosion process after standardized treatment of risk areas; Indicates the first Risk values ​​of soil erosion processes in individual high-risk communities that have not undergone standardized treatment; and These represent the minimum and maximum values ​​of the original risk level of soil erosion process at a single scale, respectively. and These represent the maximum and minimum values ​​of the data standardization mapping interval, respectively; the standardized soil erosion values ​​are all within the range of [0,1].

6. The coupling method based on the comprehensive risk of "soil erosion process-landscape pattern" according to claim 1, characterized in that... In step 2.5, the expression for the ecological risk index of the soil erosion process is as follows: In the formula, Indicates the first Ecological risk index of soil erosion process in risky communities. Indicates the first The soil erosion loss index of each high-risk community Indicates the first Risk levels of soil erosion processes after standardized treatment of risk areas.

7. The coupling method based on the comprehensive risk of "soil erosion process-landscape pattern" according to claim 1, characterized in that... In step 3, the landscape disturbance index is calculated from landscape fragmentation, landscape separation, and landscape fractal dimension, and its expression is: In the formula, for Landscape disturbance index of landscape type for Landscape fragmentation index of landscape types for Landscape separation index of landscape types for Landscape fractal dimension of a type of landscape , , The weights are assigned to the corresponding landscape indices. The expression for the landscape fragmentation index is: In the formula, For landscape The number of plaques, For landscape The total area; The expression for the landscape separation index is: In the formula, A represents the total landscape area; The expression for the landscape fractal dimension is: In the formula, For landscape circumference; The formula for calculating the landscape loss index is as follows: In the formula, For the first Landscape loss index within each high-risk community; For the first Within each high-risk community Disturbance level of similar landscapes; For the first Within each high-risk community Vulnerability of landscape types; The formula for calculating the landscape pattern hazard index is as follows: In the formula, Indicates the first Risk index of landscape pattern within each high-risk community; For the first Landscape type within risky communities The area; For the first The total area of ​​each high-risk community; The formula for calculating the landscape pattern risk index is as follows: In the formula, For the first Landscape ecological risk index of each high-risk community.

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