Landscape ecological safety dynamic evaluation method based on multi-attribute decision model

Abstract

The invention discloses a landscape ecological safety dynamic evaluation method based on a multi-attribute decision model, and the method comprises the steps: obtaining the spatial feature scale of each land utilization type through employing a gap degree landscape scale analysis method, and taking the spatial feature scale as a feature grid scale for landscape pattern analysis; calculating landscape pattern characteristic indexes under each characteristic grid scale in different periods, and constructing a regional landscape ecological safety assessment model; obtaining a landscape ecological safety index of each characteristic grid scale in a continuous time range by adopting a Lagrange interpolation method, and predicting a landscape ecological safety index value of each characteristic grid scale in a future period; a multi-attribute decision CoCoSo model is adopted to calculate the weighted sum of landscape ecological safety and the sum of index weighted products, different aggregation functions are adopted to obtain a landscape ecological safety dynamic index, and finally a natural breakpoint method is adopted to perform hierarchical and partitioned management on the landscape ecological safety dynamic index of a research area. The method can provide technical support for protection and restoration of a regional landscape ecosystem.

Description

Technical Field

[0001] The invention relates to the technical field of regional landscape ecosystem management and planning, in particular to a landscape ecological security dynamic assessment method based on a multi-attribute decision model. Background Art

[0002] The development of social productivity and urbanization has increased the intensity of land use, disrupted the balance of land use resources, and made the ecological landscape more fragmented. Its internal connectivity has declined significantly, leading to problems such as land desertification and loss of ecosystem functions, endangering regional ecological security and affecting the sustainable development of human social economy. Ecological security refers to the state in which the ecological environment can meet the needs of human sustainable development without destroying the potential of the natural environment. Comprehensive ecological security evaluation can provide an effective means for ecological security management. The evaluation of ecological security mainly includes: mathematical model method, ecological model method, digital ecological security model method and landscape model method. Among them, landscape ecological security assessment quantifies the landscape pattern characteristic index, characterizes the landscape structure and morphological change trend, and further reflects the quality of the landscape ecosystem. This method is not only easy to carry out, but also can reflect the evolution process of the quality of large-scale landscape ecosystems over a long period of time.

[0003] At present, landscape ecological security assessment is mostly limited to building models through landscape disturbance and vulnerability indexes to calculate landscape ecological sensitivity. However, as a dynamic system of landscape, the ecosystem has its own regulatory mechanism, namely adaptive capacity, which can usually be quantified through landscape diversity and uniformity index. The higher the diversity and uniformity of the landscape, the stronger the ability to make adaptive adjustments after sensitively responding to external disturbances. A single landscape sensitivity index cannot fully reflect the complex impact of land use changes on landscape ecosystems. Landscape ecological security should be comprehensively assessed in combination with landscape sensitivity and landscape adaptability. In addition, the current dynamic assessment of regional landscape ecological security still evaluates the landscape ecological security index of multiple periods separately and compares their spatiotemporal variation characteristics. This method is essentially a static assessment method that cannot describe the evolution process of the regional landscape ecosystem and ignores the interaction between the landscape ecological security indexes of different periods. Summary of the invention

[0004] In order to solve the problems existing in the prior art, the purpose of the present invention is to provide a dynamic assessment method of landscape ecological security based on a multi-attribute decision-making model, which can provide a theoretical basis and technical support for the protection and restoration of regional landscape ecosystems.

[0005] To achieve the above object, the technical solution adopted by the present invention is: a dynamic assessment method of landscape ecological security based on a multi-attribute decision-making model, comprising the following steps: Step 1: With the help of fractal theory, the gap index of each land use type in the study area at different spatial scales is obtained by using the gap landscape scale analysis method, and the spatial characteristic scale is obtained, which is used as the characteristic grid scale for landscape pattern analysis; Step 2: Based on the long-term land use type layer of the study area, calculate the landscape pattern characteristic index at each characteristic grid scale in different periods, and construct a regional landscape ecological security assessment model from the perspectives of landscape sensitivity and landscape adaptability; Step 3: Based on the landscape ecological security index of each characteristic grid scale at different periods, the Lagrange interpolation method is used to obtain the landscape ecological security index of each characteristic grid scale within a continuous time range, and the LSTM model is used to predict the landscape ecological security index value of each characteristic grid scale in the future period; Step 4: Based on the spatial distribution layers of landscape ecological security index at each characteristic grid scale in different periods, considering the additive and multiplicative synergistic relationship between landscape ecological security indices in different periods, the multi-attribute decision-making CoCoSo model is used to calculate the weighted sum and exponential weighted product sum of landscape ecological security, and different aggregation functions are used to obtain the dynamic index of landscape ecological security. Finally, the natural breakpoint method is used to carry out hierarchical and regional management of the dynamic index of landscape ecological security in the study area.

[0006] As a further improvement of the present invention, in step 2, the landscape pattern characteristic index includes landscape fragmentation, landscape separation, landscape richness and landscape interference.

[0007] As a further improvement of the present invention, the calculation method of the landscape fragmentation is specifically as follows: ; in, C ki is the landscape fragmentation, NP ki Is a grid k Neidi i The number of patches of each landscape type, CA ki Is a grid k Neidi i The area of ​​each landscape type; The calculation method of the landscape separation degree is specifically as follows: ; in, S ki is the landscape separation, TA k Is a grid k The total area of ​​various types of landscapes within the area; The calculation method of the landscape richness is as follows: ; in, D ki For landscape richness, m ki It is a statistical cell k Neidi i The total number of patches in the landscape type, M k It is a statistical cell k The total number of plaques, TN k It is a statistical cell k total number of inner plaques; The calculation method of the landscape interference degree is as follows: ; in, U ki is the landscape disturbance degree, a,b,c Landscape fragmentation C ki , Separation S ki , Dominance D ki The weight of .

[0008] As a further improvement of the present invention, in step 2, a regional landscape ecological security assessment model is constructed from the two perspectives of landscape sensitivity and landscape adaptability as follows: The landscape sensitivity index is calculated as follows: ; In the formula, LSI k Representation Grid k Landscape sensitivity index in ; U ki Representation Grid k Middle i Landscape disturbance degree of each land use type; V ki Representation Grid k Middle i Landscape vulnerability of different land use types; The calculation formula of landscape adaptability index is as follows: ; In the formula, PRD k Is a grid k patch richness density in ; SHDI k Representative Grid k The diversity of the landscape; SHEI kRepresentative Grid k Shannon evenness index in; The calculation formula of the landscape ecological security index that integrates landscape sensitivity and landscape suitability is as follows: ; In the formula, LESI k represents the grid k LES ; LSI k Representation Grid k Landscape sensitivity index in ; A ki Representation Grid k Middle i Area of ​​each land use type; A k Representation Grid k The total area of ​​all land use types in; LAI k Representation Grid k Landscape adaptability index in .

[0009] As a further improvement of the present invention, in step 4, the multi-attribute decision-making CoCoSo model is a comprehensive exponential weighted product based on a simple weighted model, and its calculation formula is as follows: ; ; In the formula, Indicates the number of different periods, that is, the number of years of data used for calculation; For the The grid Annual landscape ecological security index; For the The weight of the annual landscape ecological security index, is the weighted sum of the variable values; It is the sum of weighted products of the landscape ecological security index; Apply aggregation methods to and To summarize: ; ; ; ; Where: It indicates the number of evaluated units, i.e. the number of grids; represent and The arithmetic mean of the sum; represent and The sum of the quantified ecological security of the landscape relative to the best case scenario; About and The balanced compromise score of Express or Preferences, Right now The dynamic index of landscape ecological security of grid units can be based on The spatiotemporal analysis characteristics of the dynamic index of regional landscape ecological security were studied by value analysis.

[0010] The present invention couples landscape characteristic scale analysis, landscape ecological security assessment model construction and landscape ecological security prediction, and quantitatively evaluates the landscape ecological security of the region at different periods from a grid scale. On this basis, the multi-attribute decision-making CoCoSo model is adopted to obtain the dynamic assessment index of landscape ecological security, and the index is graded and zoned, providing a theoretical basis and technical support for the protection and restoration of regional landscape ecosystems.

[0011] The beneficial effects of the present invention are: 1. The present invention constructs a regional landscape ecological security assessment model from the perspectives of landscape sensitivity and landscape adaptability, taking into account the degree of influence of natural and human activities on the landscape, the sensitivity of landscape types to external interference, and the adaptability and recovery ability of landscapes under external interference. It can more comprehensively reflect the impact of land use changes on landscape ecosystems, make up for the shortcomings of traditional landscape ecological security that only considers landscape sensitivity, and provide method support for accurately assessing landscape ecological security; 2. Based on the multi-attribute decision-making model, the dynamic assessment method of landscape ecological security constructed by the present invention takes into account the additive and multiplicative synergistic relationship between landscape ecological security indexes in different periods of a long time series, which can better reflect the dynamic evolution process of the landscape ecosystem, make up for the shortcomings of the traditional static assessment of landscape ecological security, and provide a more reasonable method support for the dynamic assessment of regional landscape ecological security; 3. The present invention provides a new method for reflecting the spatial distribution of the dynamic assessment index of landscape ecological security under specific landscape management, and classifies and zones the comprehensive index, identifies regional landscape ecological security dynamic index protection areas and restoration areas, and improves the efficiency of regional landscape ecosystem management. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a flow chart of an embodiment of the present invention; FIG. 2 (a) is a distribution diagram of the gap index of agricultural land in an embodiment of the present invention; FIG2( b ) is a distribution diagram of the gap index when the land use type is forest land in an embodiment of the present invention; FIG2( c ) is a distribution diagram of the gap index when the land use type is grassland in an embodiment of the present invention; FIG2( d ) is a distribution diagram of the interstitial index of the land use type of water body in an embodiment of the present invention; FIG2( e ) is a distribution diagram of the gap index when the land use type is construction land in an embodiment of the present invention; FIG2( f ) is a distribution diagram of the gap index of unused land in an embodiment of the present invention; Figure 3 It is a spatial distribution map of landscape sensitivity index at a grid scale in an embodiment of the present invention; Figure 4 is a spatial distribution map of the landscape adaptability index at a grid scale in an embodiment of the present invention; Figure 5 It is a spatial distribution map of the landscape ecological security index at the grid scale in an embodiment of the present invention; Figure 6 It is a predicted spatial distribution map of landscape ecological security index at a grid scale in an embodiment of the present invention; Figure 7 It is a graded zoning map of the dynamic index of landscape ecological security at the grid scale in an embodiment of the present invention. DETAILED DESCRIPTION

[0013] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0014] Example 1

[0015] like Figure 1 As shown, a method for dynamic assessment of landscape ecological security based on a multi-attribute decision-making model is a new method for dynamic assessment of regional landscape ecological security based on the synergistic relationship between the addition and multiplication of landscape ecological security indexes in different periods of a long time series, and is based on gap landscape scale analysis, landscape ecological security assessment model, Lagrange interpolation, LSTM prediction model, multi-attribute decision CoCoSo model and spatial analysis technology. The method includes the following steps: S1. With the help of fractal theory, the gap index of each land use type in the study area at different spatial scales is obtained by using the gap landscape scale analysis method, and the spatial characteristic scale is obtained, that is, the spatial distribution of land use types tends to be homogeneous at this spatial characteristic scale, and it is used as the characteristic grid scale for landscape pattern analysis, which is also the basic calculation unit for landscape ecological security evaluation; S2. Based on the long-term land use type layer of the study area, the Fragstats landscape index analysis software was used to calculate the landscape pattern characteristic index (including landscape fragmentation, landscape separation, landscape richness, and landscape disturbance) at each grid scale in different periods, and a regional landscape ecological security assessment model was constructed from the two perspectives of landscape sensitivity and landscape adaptability; S3. Based on the landscape ecological security index of each grid at different times, the Lagrange interpolation method is used to obtain the landscape ecological security index of each grid within a continuous time range, and the LSTM model is used to predict the landscape ecological security index value of each grid in the future period; S4. In order to reflect the dynamic change process of regional landscape ecological security, based on the spatial distribution layers of landscape ecological security index at different grid scales in different periods, considering the additive and multiplicative synergistic relationship between landscape ecological security indexes in different periods, the multi-attribute decision-making CoCoSo model is adopted to calculate the weighted sum and the sum of the weighted products of the landscape ecological security, and different aggregation functions are used to obtain the dynamic index of landscape ecological security. Finally, the natural breakpoint method is used to hierarchically and regionally manage the dynamic index of landscape ecological security in the study area. In step S2, the ecological security index of each grid landscape is calculated. The landscape disturbance degree characterizes the heterogeneity and diversity characteristics of the landscape under natural and human disturbances, and indicates the degree of influence of natural and human activities on the landscape, which is related to the landscape fragmentation, separation and dominance. Landscape fragmentation refers to the degree of fragmentation of landscape types at a specific time and specific nature. The greater the degree of adverse human disturbance, the more fragmented the landscape type; landscape separation reflects the spatiotemporal distribution characteristics of human-natural factors on landscape disturbance; and landscape dominance is a sensitive indicator for analyzing the changes in diversity and heterogeneity of different landscape types at different times, which is related to the coverage, density and frequency of landscape types; various landscape types show differences in sensitivity and anti-interference in the process of natural-human disturbance, that is, the landscape has fragility and landscape adaptability. Landscape fragility indicates the degree of sensitivity of landscape types to external disturbances. The larger the value, the more sensitive it is to external disturbances. Landscape adaptability is the ability of landscapes to adapt and recover under external disturbances, which is closely related to the structure, function, diversity and uniformity of distribution of landscapes. The larger the value, the stronger the ability of landscapes to adapt and recover under external disturbances. Finally, a regional landscape ecological security assessment model was constructed from the two perspectives of landscape sensitivity and landscape adaptability.

[0016] The calculation formulas for different landscape pattern characteristic indexes and landscape disturbance are shown in Table 1: Table 1 Calculation instructions for the correlation between landscape pattern characteristic index and landscape disturbance degree

[0017] The landscape sensitivity index can be calculated as follows: ; In the formula, LSI k Representation Grid k Landscape sensitivity index in ; U ki Representation Grid k Middle i Landscape disturbance degree of each land use type; V ki Representation Grid k Middle i The landscape vulnerability of the land use types is shown in Table 2: Table 2 Landscape vulnerability of each land use type

[0018] The calculation formula of landscape adaptability index is as follows: ; In the formula, PRD k Is a grid k patch richness density in ; SHDI k Representative Grid k The diversity of the landscape; SHEI k Representative Grid k Shannon's Evenness Index, high SHEI k The value indicates that there is no obvious dominant landscape class, and each type of landscape is in the grid k Evenly distributed in the middle.

[0019] The calculation formula of the landscape ecological security index that integrates landscape sensitivity and landscape suitability is as follows: ; In the formula, LESI k Representation Grid k In LES ; LSI k Representation Grid k Landscape sensitivity index in ; A ki Representation Grid k Middle i Area of ​​each land use type; A k Representation Grid k The total area of ​​all land use types in; LAI k Representation Grid kLandscape adaptability index in .

[0020] The calculation of the dynamic index of landscape ecological security in step S4 is to reflect the dynamic change process of regional landscape ecological security. The CoCoSo model is used to aggregate the spatial distribution layers of the landscape ecological security index at different grid scales in the long-term series obtained based on the gap landscape scale analysis-landscape ecological security index calculation-future landscape ecological security index prediction, and calculate the dynamic index of landscape ecological security in the study area. CoCoSo is a multi-attribute decision-making method that can provide a compromise solution for different aggregation functions based on the simple additive weighting model. The calculation formula is: ; ; In the formula, Indicates the number of different periods, that is, the number of years of data used for calculation; For the The grid Annual landscape ecological security index; For the The weight of the annual landscape ecological security index is generally considered to be equally important, so it is given equal weight. =1 / n . is the weighted sum of the variable values; is the sum of the weighted products of the landscape ecological security indexes. Based on this, the aggregation method is used to and To summarize.

[0021] ; ; ; ; Where: It indicates the number of evaluated units, i.e. the number of grids; represent and The arithmetic mean of the sum; represent and The sum of the quantified ecological security of the landscape relative to the best case scenario; About and The balanced compromise score of Express or preference, generally believed to be and There is no preference, so Set to 0.5. Right now The dynamic index of landscape ecological security of grid units can be based on The spatiotemporal analysis characteristics of the dynamic index of regional landscape ecological security were studied by value analysis.

[0022] This embodiment proposes to couple landscape characteristic scale analysis-landscape ecological security static assessment-landscape ecological security prediction with the multi-attribute decision-making CoCoSo model, and then obtain the landscape ecological security dynamic index under the characteristic calculation grid unit, which can more accurately reflect the interaction relationship between landscape ecological security indices in different periods of long time series, as well as the dynamic evolution process of landscape ecosystems. It integrates landscape ecology, geology, management and environmental science, accurately assesses the regional landscape ecological security dynamic index, provides methodological support for improving the quality and function of regional landscape ecosystems, and provides data support for the hierarchical and zoning management of regional landscape ecological security dynamic indexes.

[0023] Example 2 This embodiment is further described in detail with reference to a certain river basin. Figure 1 As shown in the figure, a dynamic assessment method of landscape ecological security based on a multi-attribute decision-making model is proposed. This method is a new method of dynamic assessment of landscape ecological security based on the combination of gap landscape scale analysis, landscape ecological security assessment model, Lagrange interpolation, LSTM prediction model, multi-attribute decision CoCoSo model and spatial analysis technology. It specifically includes the following contents: S1. With the help of fractal theory, the gap index of six land use types in the basin (30 m×30 m in this embodiment) at different spatial scales was obtained by using the gap landscape scale analysis method, as shown in Figure 2 (a) to Figure 2 (f), and the spatial characteristic scale was obtained, that is, the spatial distribution of land use types at this spatial characteristic scale tends to be homogeneous, and it was used as the characteristic grid scale for landscape pattern analysis, which is also the basic calculation unit for landscape ecological security evaluation in the region (3 km×3 km in this embodiment); S2. Based on the long-term land use type layer of the watershed (1980, 1990, 1995, 2000, 2005, 2008, 2010, 2015, 2018, and 2020), the Fragstats landscape index analysis software was used to calculate the landscape pattern characteristic index (including landscape fragmentation, landscape separation, landscape richness, and landscape disturbance) at each grid scale in the previous different periods, and a regional landscape ecological security assessment model was constructed from the two perspectives of landscape sensitivity and landscape adaptability. The spatial distribution map of the landscape sensitivity index and the spatial distribution map of the landscape adaptability index are shown below. Figure 3 and Figure 4 As shown; S3. Based on the landscape ecological security index of each grid in different periods, the Lagrange interpolation method is used to obtain the landscape ecological security index of each grid within a continuous time range, as follows: Figure 5 As shown, the LSTM model is used to predict the landscape ecological security index value of each grid in the future period (set to 2025 and 2030 in this embodiment), as shown in Figure 6 As shown; S4. In order to reflect the dynamic change process of the landscape ecological security of the watershed, based on the spatial distribution layers of the landscape ecological security index at each grid scale in different periods, the addition and multiplication synergy relationship between the landscape ecological security indexes in different periods (1980-2025, 1980-2030) was considered, and the multi-attribute decision-making CoCoSo model was used to calculate the weighted sum and the sum of the exponential weighted products of the landscape ecological security. Different aggregation functions were used to obtain the dynamic index of landscape ecological security, such as Figure 7 As shown, the natural breakpoint method is finally used to carry out hierarchical and zoning management of the dynamic index of watershed landscape ecological security; In the step S2, the ecological security index of each grid landscape in the watershed is calculated. The landscape disturbance degree characterizes the heterogeneity and diversity characteristics of the landscape under natural and human disturbances, and indicates the degree of influence of natural and human activities on the landscape, which is related to the landscape fragmentation, separation and dominance. The landscape fragmentation refers to the degree of fragmentation of the landscape type at a specific time and specific nature. The greater the degree of adverse human disturbance, the more fragmented the landscape type; the landscape separation reflects the temporal and spatial distribution characteristics of human-natural factors on the landscape disturbance; and the landscape dominance is a sensitive indicator for analyzing the changes in diversity and heterogeneity of different landscape types at different times, which is related to the coverage, density and frequency of the landscape type; the sensitivity and anti-interference of various landscape types in the process of natural-human disturbance show more significant differences, that is, the landscape has fragility and landscape adaptability. Landscape fragility indicates the degree of sensitivity of the landscape type to external disturbances. The larger the value, the more sensitive it is to external disturbances. Landscape adaptability is the ability of the landscape to adapt and recover under external disturbances, which is closely related to the structure, function, diversity and uniformity of distribution of the landscape. The larger the value, the stronger the ability to adapt and recover with external disturbances. Finally, a regional landscape ecological security assessment model was constructed from the two perspectives of landscape sensitivity and landscape adaptability.

[0024] The landscape sensitivity index can be calculated as follows: ; In the formula, LSI k Representation Grid k Landscape sensitivity index in ; U ki Representation Grid k Middle i Landscape disturbance degree of each land use type; V ki Representation Grid k Middle i Landscape vulnerability of different land use types.

[0025] The calculation formula of landscape adaptability index is as follows: ; In the formula, PRD k Is a grid k patch richness density in ; SHDI k Representative Grid k The diversity of the landscape; SHEI k Representative Grid k Shannon's Evenness Index, high SHEI kThe value indicates that there is no obvious dominant landscape class, and each type of landscape is in the grid k Evenly distributed in the middle.

[0026] The calculation formula of the landscape ecological security index that integrates landscape sensitivity and landscape suitability is as follows: ; In the formula, LESI k Representation Grid k In LES ; LSI k Representation Grid k Landscape sensitivity index in ; A ki Representation Grid k Middle i Area of ​​each land use type; A k Representation Grid k The total area of ​​all land use types in; LAI k Represents the landscape suitability index in grid k.

[0027] The calculation of the dynamic index of landscape ecological security in step S4 is to reflect the dynamic change process of the landscape ecological security of the watershed. The CoCoSo model is used to aggregate the spatial distribution layers of the landscape ecological security index at the grid scale of different periods (1980-2025, 1980-2030) of the long-term series obtained based on the gap landscape scale analysis-landscape ecological security index calculation-future landscape ecological security index prediction to calculate the dynamic index of the landscape ecological security of the watershed. CoCoSo is a multi-attribute decision-making method that can provide a compromise solution for different aggregation functions. Its calculation formula is: ; ; In the formula, Indicates the number of different periods, that is, the number of years of data used for calculation; For the The grid Annual landscape ecological security index; For the The weight of the annual landscape ecological security index is generally considered to be equally important, so it is given equal weight. =1 / n . is the weighted sum of the variable values; is the sum of the weighted products of the landscape ecological security indexes. Based on this, the aggregation method is used to and To summarize.

[0028] ; ; ; ; Where: It indicates the number of evaluated units, i.e. the number of grids; represent and The arithmetic mean of the sum; represent and The sum of the quantified ecological security of the landscape relative to the best case scenario; About and The balanced compromise score of Express or preference, generally believed to be and There is no preference, so Set to 0.5. Right now The dynamic index of landscape ecological security of grid units can be based on The spatiotemporal analysis characteristics of the dynamic index of regional landscape ecological security were studied by value analysis.

[0029] The above-mentioned embodiments only express the specific implementation of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A dynamic assessment method for landscape ecological security based on a multi-attribute decision-making model, characterized in that: The following steps are involved: Step 1: With the help of fractal theory, the gap index of each land use type in the study area at different spatial scales is obtained by using the gap landscape scale analysis method, and the spatial characteristic scale is obtained, which is used as the characteristic grid scale for landscape pattern analysis; Step 2: Based on the long-term land use type layer of the study area, calculate the landscape pattern characteristic index at each characteristic grid scale in different periods, and construct a regional landscape ecological security assessment model from the perspectives of landscape sensitivity and landscape adaptability; Step 3: Based on the landscape ecological security index of each characteristic grid scale at different periods, the Lagrange interpolation method is used to obtain the landscape ecological security index of each characteristic grid scale within a continuous time range, and the LSTM model is used to predict the landscape ecological security index value of each characteristic grid scale in the future period; Step 4: Based on the spatial distribution layers of landscape ecological security index at each characteristic grid scale in different periods, considering the additive and multiplicative synergistic relationship between landscape ecological security indices in different periods, the multi-attribute decision-making CoCoSo model is used to calculate the weighted sum and exponential weighted product sum of landscape ecological security, and different aggregation functions are used to obtain the dynamic index of landscape ecological security. Finally, the natural breakpoint method is used to carry out hierarchical and regional management of the dynamic index of landscape ecological security in the study area.

2. The method for dynamic assessment of landscape ecological security based on a multi-attribute decision-making model according to claim 1 is characterized in that: In step 2, the landscape pattern characteristic index includes landscape fragmentation, landscape separation, landscape richness and landscape disturbance.

3. The method for dynamic assessment of landscape ecological security based on a multi-attribute decision-making model according to claim 2 is characterized in that: The calculation method of the landscape fragmentation is as follows: ； in, C ki is the landscape fragmentation, NP ki Is a grid k Neidi i The number of patches of each landscape type, CA ki Is a grid k Neidi i The area of ​​each landscape type; The calculation method of the landscape separation degree is as follows: ； in, S ki is the landscape separation, TA k Is a grid k The total area of ​​various types of landscapes within the area; The calculation method of the landscape richness is as follows: ； in, D ki For landscape richness, m ki It is a statistical cell k Neidi i The total number of patches in the landscape type, M k It is a statistical cell k The total number of plaques, TN k It is a statistical cell k total number of inner plaques; The calculation method of the landscape disturbance degree is as follows: ； in, U ki is the landscape disturbance degree, a,b,c Represents the degree of landscape fragmentation C ki , Separation S ki , Dominance D ki The weight of .

4. The method for dynamic assessment of landscape ecological security based on a multi-attribute decision-making model according to claim 1 is characterized in that: In step 2, the regional landscape ecological security assessment model is constructed from the two perspectives of landscape sensitivity and landscape adaptability as follows: The landscape sensitivity index is calculated as follows: ； In the formula, LSI k Representation Grid k Landscape sensitivity index in ; U ki Representation Grid k Middle i Landscape disturbance degree of each land use type; V ki Representation Grid k Middle i Landscape vulnerability of different land use types; The calculation formula of landscape adaptability index is as follows: ； In the formula, PRD k Is a grid k patch richness density in ; SHDI k Representative Grid k The diversity of the landscape; SHEI k Representative Grid k Shannon evenness index in; The calculation formula of landscape ecological security index integrating landscape sensitivity and landscape suitability is as follows: ； In the formula, LESI k Representation Grid k In LES ; LSI k Representation Grid k Landscape sensitivity index in ; A ki Representation Grid k Middle i Area of ​​each land use type; A k Representation Grid k The total area of ​​all land use types in; LAI k Representation Grid k Landscape adaptability index in .

5. The method for dynamic assessment of landscape ecological security based on a multi-attribute decision-making model according to claim 1 is characterized in that: In step 4, the multi-attribute decision-making CoCoSo model is a comprehensive exponential weighted product based on a simple weighted model, and its calculation formula is as follows: ； ； In the formula, Indicates the number of different periods, that is, the number of years of data used for calculation; For the The first Annual landscape ecological security index; For the The weight of the annual landscape ecological security index, is the weighted sum of the variable values; It is the sum of weighted products of the landscape ecological security index; Apply aggregation methods to and To summarize: ； ； ； ； Where: It indicates the number of evaluated units, i.e. the number of grids; represent and The arithmetic mean of the sum; represent and The sum of the quantified ecological security of the landscape relative to the best case scenario; About and The balanced compromise score of Express or Preferences, Right now The dynamic index of landscape ecological security of grid units can be The spatiotemporal analysis characteristics of the dynamic index of regional landscape ecological security were studied by value analysis.

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