Construction method and system of artificial river channel simulating natural landscape pattern

Abstract

The invention provides a construction method and system of an artificial river channel imitating a natural landscape pattern, and relates to a construction method of an artificial river channel, the method comprises the following steps: determining a target to be planned and constructed through a fractal geometry theory, the constructed target comprising a landscape type of the artificial river channel, the number of plaques or the total number of the plaques of the artificial river channel; each landscape type plaque edge length and habitat type; a landscape pattern index is calculated according to the constructed target, the landscape pattern index comprises landscape patches, landscape shapes and landscape diversity, and the landscape pattern of the artificial river channel is determined according to the landscape pattern index; according to the landscape pattern of the artificial river channel, referring to landscape heterogeneity and ecological benefits, establishing an artificial river channel landscape pattern model; and evaluating the change of each landscape element of the artificial river. The diversity and stability of the ecological system are improved, and the landscape pattern and the ecological function are optimized.

Description

Technical Field

[0001] The invention relates to a method for constructing an artificial river channel, in particular to a method for constructing an artificial river channel imitating a natural landscape pattern. Background Art

[0002] As an important part of urban water conservancy infrastructure, artificial waterways play a key role in flood control, drainage, water resources allocation, etc. However, the construction of traditional artificial waterways focuses on engineering functional needs, ignoring their ecosystem service functions and integration with natural landscape patterns.

[0003] In terms of landscape pattern, most artificial rivers have many problems. First, the design of landscape patches is unreasonable. The patch types are single, mainly hard revetments and simple green vegetation, lacking the rich and diverse patch types in natural ecosystems, such as wetlands, shoals, woodlands, etc. This makes the river ecosystem structure simple and unable to provide a variety of habitats and reproduction places for various organisms. Second, the landscape shape is too regular. Artificial rivers often present straight lines or simple geometric shapes, which are very different from the winding shapes of natural rivers. This regular shape changes the natural state of water flow, accelerates the speed of water flow, increases the risk of riverbank scouring, and also destroys the continuity and stability of biological habitats, reducing the living space of organisms. Third, the landscape diversity is lacking. The overall landscape lacks hierarchy and complexity, and the selection of plant species is limited, mostly common garden plants, without fully considering the ecological adaptability and biodiversity needs of plants. Animal communities are difficult to form due to the lack of suitable habitats and food sources, resulting in biodiversity far lower than that of natural river ecosystems, and poor ecosystem stability and self-repair ability.

[0004] As people's awareness of ecological environment protection continues to increase, it is urgent to construct artificial rivers that imitate natural landscape patterns. This construction method aims to learn from the landscape pattern characteristics of natural rivers, optimize the ecological functions of artificial rivers, improve biodiversity, enhance the value of ecosystem services, and achieve harmonious coexistence between artificial rivers and urban ecological environment. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method and system for constructing an artificial river channel that simulates a natural landscape pattern, which not only improves the diversity and stability of the ecosystem, but also optimizes the landscape pattern and ecological function.

[0006] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0007] In a first aspect, a method for constructing an artificial river channel simulating a natural landscape pattern comprises:

[0008] Through fractal geometry theory, the objectives of the planned construction are determined, including the landscape type of the artificial river, the number of patches or the total number of patches of the artificial river, the edge length of each landscape type patch, and the habitat type;

[0009] According to the construction objectives, the landscape pattern index is calculated. The landscape pattern index includes landscape patches, landscape shapes and landscape diversity. The landscape pattern of the artificial river is determined based on the landscape pattern index.

[0010] According to the landscape pattern of artificial waterways, the landscape pattern model of artificial waterways is established with reference to landscape heterogeneity and ecological benefits;

[0011] Assess changes in landscape elements of artificial waterways.

[0012] Furthermore, through the theory of fractal geometry, the objectives of the planned construction are determined. The objectives of the construction include the landscape type of the artificial river, the number of patches or the total number of patches of the artificial river, the edge length of each landscape type patch, and the habitat type, including:

[0013] Setting fractal parameters, wherein the fractal parameters include fractal dimension and curvature coefficient;

[0014] According to the given fractal parameters, based on the iterative function system algorithm, a series of points are generated to determine the position of the river centerline;

[0015] Adjust the generated river channel plan morphology according to the GIS data;

[0016] Set a fractal parameter to describe the cross-sectional roughness;

[0017] According to the fractal parameters, the profile of the river cross section is generated using a random fractal algorithm;

[0018] According to the cross-sectional profile and cross-sectional morphology of the river channel, the aquatic habitat can be obtained;

[0019] Adjust the curvature of the curved part of the river channel according to the simulation results of the computational fluid dynamics model, and plant aquatic plants in the slow-flow area formed at the bend of the river channel;

[0020] In river bank design, the irregular river bank lines generated by fractal parameters are used to increase leisure facilities and landscape forest belts.

[0021] Furthermore, according to the construction objectives, the landscape pattern index is calculated. The landscape pattern index includes landscape patches, landscape shapes and landscape diversity. According to the landscape pattern index, the landscape pattern of the artificial river is determined, including:

[0022] Conduct surveys or investigations on the construction objectives, and calculate landscape patches, landscape shapes, and landscape diversity. Landscape patches include patch density and maximum patch index, landscape shapes include edge density and landscape shape index, and landscape diversity includes landscape spread index, Shannon landscape diversity index, and Shannon landscape evenness index.

[0023] According to the patch density, maximum patch index, edge density, landscape shape index, landscape spread index, Shannon landscape diversity index and Shannon landscape uniformity index, the landscape type, number of patches or the total number of patches of artificial waterways, the edge length of each landscape type and habitat type within the red line of artificial waterway planning and construction are determined;

[0024] According to the landscape pattern index, the landscape pattern was determined by Fragstats software.

[0025] Furthermore, the construction objectives are investigated or surveyed to calculate the landscape patches, landscape shapes and landscape diversity, including:

[0026] Landscape patches include patch density and maximum patch index;

[0027] By PD=n i / A calculates the plaque density, where n i is the number of patches of the i-th landscape type or the total number of patches in the study area, A is the total area of ​​the region, and PD refers to the number of patches per hectare, which is used to describe the diversity of landscape types. The larger the PD, the higher the degree of spatial heterogeneity.

[0028] pass Calculate the maximum plaque index, where a ij is the maximum patch area of ​​the i-th landscape type or the largest patch area in the study area, A is the total area of ​​the region, and LPI is the maximum patch index, which is used to determine the proportion of the largest patch in the entire landscape.

[0029] Furthermore, the construction objectives are investigated or surveyed to calculate the landscape patches, landscape shapes and landscape diversity, including:

[0030] Landscape shape includes edge density and landscape shape index;

[0031] pass Calculate the edge density, where m is the total number of landscape element types at a certain spatial resolution within the study area, and p is ij is the length of the boundary between the i-th type of landscape patch and the adjacent j-th type of landscape element patch in the landscape, A is the total area of ​​the region, and ED is the edge density, which represents the edge length per unit area in the landscape;

[0032] By LSI=e i / min(e i ) Calculate the landscape shape index, e i is the total edge length of type i in the landscape, min(e i ) is the minimum edge length of landscape type i when the total area is constant and it is aggregated into a simple and compact landscape patch. LSI is the landscape shape index, which indicates the degree of aggregation of the landscape space.

[0033] Furthermore, the construction objectives are investigated or surveyed to calculate the landscape patches, landscape shapes and landscape diversity, including:

[0034] Landscape diversity includes landscape spread index, Shannon landscape diversity index and Shannon landscape evenness index;

[0035] pass Calculate the landscape spread index, where m is the total number of patch types, P i is the proportion of landscape area occupied by patch type i, g ik is the number of adjacent grid cells between patch types i and k, CONTAG is the landscape contagion index, which describes the degree of aggregation or extension trend of different patch types in the landscape;

[0036] pass Calculate the Shannon landscape diversity index, where p i is the area proportion of landscape type i in the landscape, m is the total number of landscape types, and SHDI is the Shannon landscape diversity index;

[0037] pass Calculate the Shannon landscape evenness index, where p i is the area proportion of landscape type i in the landscape, m is the total number of landscape types, and SHEI is the Shannon landscape evenness index.

[0038] Furthermore, according to the landscape pattern of artificial rivers, with reference to landscape heterogeneity and ecological benefits, an artificial river landscape pattern model is established, including:

[0039] Landscape heterogeneity includes longitudinal heterogeneity, lateral heterogeneity and vertical heterogeneity;

[0040] Ecological benefits include habitat function, filtering and barrier effects, and source-sink effects;

[0041] According to the landscape pattern, landscape heterogeneity and ecological benefits of artificial rivers, a landscape pattern model of artificial rivers is constructed.

[0042] 8. A system for constructing an artificial river channel imitating a natural landscape pattern, characterized by comprising:

[0043] The planning module is used to determine the objectives of the planned construction through fractal geometry theory. The objectives of the construction include the landscape type of the artificial river, the number of patches or the total number of patches of the artificial river, the edge length of each landscape type patch, and the habitat type;

[0044] The construction module is used to calculate the landscape pattern index according to the construction objectives. The landscape pattern index includes landscape patches, landscape shapes and landscape diversity, and to determine the landscape pattern of the artificial river based on the landscape pattern index; to establish an artificial river landscape pattern model based on the landscape pattern of the artificial river and with reference to landscape heterogeneity and ecological benefits; and to evaluate the changes in various landscape elements of the artificial river.

[0045] According to a third aspect, a computing device includes:

[0046] one or more processors;

[0047] The storage device is used to store one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement the method described.

[0048] In a fourth aspect, a computer-readable storage medium stores a program, and when the program is executed by a processor, the method described is implemented.

[0049] The above solution of the present invention includes at least the following beneficial effects:

[0050] The landscape type, number of patches, patch edge length and habitat type of artificial rivers are planned by fractal geometry theory, so that artificial rivers can imitate the complexity and diversity of natural rivers. Diversity not only provides rich habitats and food sources for aquatic and terrestrial organisms, but also enhances the stability and self-repair ability of the ecosystem. Calculating landscape pattern indexes, such as landscape patches, landscape shapes and landscape diversity, helps to scientifically and rationally layout the landscape elements of artificial rivers. By optimizing the landscape pattern, the water flow state can be improved, the risk of riverbank scouring can be reduced, and the ecological functions of the river can be improved, such as purifying water quality and regulating microclimate. Artificial rivers with natural landscape patterns can attract more species of organisms to live and reproduce, thereby improving biodiversity. The increase in biodiversity not only enriches the composition of the ecosystem, but also improves the service value of the ecosystem, such as providing ecological landscapes with viewing, education, scientific research and other functions. The imitation of natural landscape pattern design of artificial rivers makes urban water conservancy infrastructure closer to nature, enhances the ecological livability of the city, helps to enhance people's awareness of ecological environmental protection, and promotes the practice of the concept of harmonious coexistence between man and nature in urban construction. Through scientific and reasonable landscape pattern design, artificial rivers can better play the role of flood control and drainage. The river design that imitates natural landscape helps to slow down the flow of water and increase the retention time of water bodies, thereby improving the city's flood control and drainage capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 It is a flow chart of a method for constructing an artificial river channel simulating a natural landscape pattern provided by an embodiment of the present invention.

[0052] Figure 2 It is a schematic diagram of a system for constructing an artificial river channel simulating a natural landscape pattern provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0053] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in a form and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0054] like Figure 1 As shown, an embodiment of the present invention provides a method for constructing an artificial river channel simulating a natural landscape pattern, the method comprising the following steps:

[0055] Step 11, using fractal geometry theory, determine the objectives of the planned construction, including the landscape type of the artificial river, the number of patches or the total number of patches of the artificial river, the edge length of each landscape type patch, and the habitat type;

[0056] Step 12, according to the construction objectives, calculate the landscape pattern index, which includes landscape patches, landscape shapes and landscape diversity, and determine the landscape pattern of the artificial river according to the landscape pattern index;

[0057] Step 13, establishing an artificial river landscape pattern model based on the landscape pattern of the artificial river, with reference to landscape heterogeneity and ecological benefits;

[0058] Step 14: Evaluate the changes in landscape elements of the artificial river.

[0059] In the embodiment of the present invention, the fractal geometry theory provides a scientific basis for the planning and construction of artificial waterways, making the determination of landscape types, the setting of the number of patches, and the planning of habitat types more reasonable and in line with the laws of nature. Through the fractal geometry theory, the edge length of each landscape type patch can be accurately calculated, providing data support for the refined design of the landscape, making the landscape of the artificial waterway more natural and harmonious. Guided by ecological benefits, it is ensured that the goals of planning and construction not only meet human aesthetic needs, but also meet the healthy and stable development of the ecosystem. By calculating the landscape pattern index, such as landscape patches, landscape shapes, and landscape diversity, the landscape pattern of the artificial waterway can be quantitatively evaluated, providing a data basis for the optimization of the landscape pattern. The landscape pattern index can be used as a basis for objective comparison between different planning schemes to help decision makers choose the optimal landscape pattern scheme. According to the calculation results of the landscape pattern index, the landscape design of the artificial waterway can be guided, so that the landscape is more in line with the principles of ecological aesthetics and ecological balance. By establishing an artificial waterway landscape pattern model, the complex landscape pattern can be intuitively expressed in the form of a model, which is easy to understand and communicate. The model comprehensively considers landscape heterogeneity and ecological benefits, and ensures the scientificity and sustainability of the landscape pattern of the artificial waterway.

[0060] In a preferred embodiment of the present invention, the above step 11 determines the target of the planned construction through fractal geometry theory. The construction target includes the landscape type of the artificial river, the number of patches or the total number of patches of the artificial river, the edge length of each landscape type patch, and the habitat type, including:

[0061] Setting fractal parameters, wherein the fractal parameters include fractal dimension and curvature coefficient;

[0062] According to the given fractal parameters, based on the iterative function system algorithm, a series of points are generated to determine the position of the river centerline;

[0063] Adjust the generated river channel plan morphology according to the GIS data;

[0064] Set a fractal parameter to describe the cross-sectional roughness;

[0065] According to the fractal parameters, the profile of the river cross section is generated using a random fractal algorithm;

[0066] According to the cross-sectional profile and cross-sectional morphology of the river channel, the aquatic habitat can be obtained;

[0067] Adjust the curvature of the curved part of the river channel according to the simulation results of the computational fluid dynamics model, and plant aquatic plants in the slow-flow area formed at the bend of the river channel;

[0068] In river bank design, the irregular river bank lines generated by fractal parameters are used to increase leisure facilities and landscape forest belts.

[0069] In the embodiments of the present invention, the use of fractal geometry theory to design the morphology of artificial waterways is a non-obvious innovative technology. Rivers in natural landscape patterns have complex fractal characteristics, and their river boundaries are not simple straight lines or regular curves. In the construction of artificial waterways, the use of fractal mathematical models to simulate the meandering, width changes and other morphologies of natural rivers can better integrate with the surrounding natural environment, and also have advantages in hydraulics, such as reducing water flow velocity and soil erosion. For example, the curvature coefficient and width variation law of the river channel are determined according to specific fractal parameters, so that the water flow state of the artificial river channel is closer to that of a natural river, providing a more suitable living environment for aquatic organisms;

[0070] In a specific embodiment of the present invention, the fractal dimension can quantify the complexity of the river channel boundary. For a simple straight river channel, its fractal dimension is close to 1; while for a winding natural river channel with complex boundaries, the fractal dimension will be greater than 1. The curvature coefficient represents the ratio of the actual length of the river channel to the straight-line distance. The curvature coefficient of a natural river channel is usually high because its river channel morphology is a winding shape formed by multiple factors such as long-term water erosion and geological conditions.

[0071] Among them, the steps of using fractal parameters to determine the river morphology are:

[0072] S1 sets parameters such as fractal dimension and curvature coefficient, and can use computer algorithms to generate the planar morphology of the river.

[0073] S2 uses an Iterated Function System (IFS) algorithm to generate a series of points to determine the location of the centerline of the river according to given fractal parameters. The spatial distribution of these points will form a meandering shape with natural river characteristics. Compared with the traditional river design with regular geometric shapes (such as straight lines or simple arcs), the river plan morphology generated based on fractal parameters is closer to the river morphology in the natural landscape pattern.

[0074] During the generation process, S3 combines geographic information system (GIS) data, such as terrain and slope, to adjust the generated river channel plan morphology. For example, if the terrain has a certain slope, the bending direction and curvature of the river channel can be optimized based on the principle of gravity and water flow convergence, so that the generated river channel morphology is more in line with the laws of natural hydrology. Next, the cross-sectional morphology of the river channel is determined, and the undulations of the river channel bottom and the irregularities of the river bank are simulated according to the fractal parameters.

[0075] A fractal parameter describing the cross-sectional roughness is set by S4.

[0076] S5 uses a random fractal algorithm to generate the outline of the river cross section. In order to improve the landscape spread and strengthen the connectivity of a certain dominant patch type, it can also increase the area of ​​the dominant patch or reduce the number of grid cells of other adjacent patches.

[0077] S6 designs aquatic habitats based on the generated cross-sectional morphology. For example, areas with different depths and bottom types are generated at the bottom of the river to provide breeding and habitats for aquatic animals such as fish. Then, the river morphology generated according to the fractal parameters needs to be verified and optimized in combination with hydraulic principles. The morphology of natural rivers is adapted to their water flow characteristics. Therefore, when simulating the landscape pattern of near-natural rivers, it is necessary to ensure that the generated river morphology can produce natural water flow conditions. Through the computational fluid dynamics (CFD) model, the river geometry model generated by fractal parameters is input to analyze hydraulic parameters such as water flow velocity and water level changes. At the same time, in order to improve the Shannon landscape diversity index and increase the richness of habitat types in the proposed artificial river, by increasing the species diversity in the dominant patches, including increasing the plant population and bird population in the patches, the biodiversity of plant and bird populations is improved through the ex situ cultivation of native trees and bird attraction measures.

[0078] S7 adjusts the curvature of the curved part of the river according to the simulation results to avoid the situation where the water flow is too fast, causing the river bank to be eroded, or the water flow is stagnant to form dead water areas. In this way, the simulated river landscape pattern can not only be close to nature in form, but also simulate the natural river in hydraulic function, providing a suitable living environment for aquatic plants and animals.

[0079] S8 further optimizes the river terrain produced by the fractal parameters, specifically by planting aquatic plants in the slow-flowing area formed at the bend of the river.

[0080] S9 further integrates the river channel morphology simulated by fractal parameters with the surrounding natural landscape. Specifically, in the river bank design, the irregular river bank generated by fractal parameters is used to increase green infrastructure such as leisure facilities and landscape forest belts.

[0081] Conduct surveys or investigations on the landscape types, number of patches or the total number of patches in artificial rivers, the edge length of patches of each landscape type, and habitat types of artificial river corridors and river sections in cities or regions to determine the landscape types, number of patches or the total number of patches in artificial rivers, the edge length of patches of each landscape type, and habitat types within the red line of artificial river planning and construction;

[0082] In cities or river basins, the landscape types, number of patches of natural rivers or the total number of patches of artificial rivers, the edge length of patches of each landscape type, and habitat types are investigated or surveyed, and seven landscape pattern indices are calculated, namely patch density, maximum patch index, edge density, landscape shape index, landscape spread index, Shannon landscape diversity index and Shannon landscape uniformity index. In this way, the landscape types, number of patches or the total number of patches of artificial rivers, the edge length of patches of each landscape type, and habitat types within the red line of artificial river planning and construction are determined.

[0083] In a preferred embodiment of the present invention, the above step 12 calculates the landscape pattern index according to the construction goal, and the landscape pattern index includes landscape patches, landscape shapes and landscape diversity, and determines the landscape pattern of the artificial river according to the landscape pattern index, including:

[0084] Step 121, investigating or surveying the construction target, calculating landscape patches, landscape shapes and landscape diversity, wherein the landscape patches include patch density and maximum patch index, the landscape shapes include edge density and landscape shape index, and the landscape diversity includes landscape spread index, Shannon landscape diversity index and Shannon landscape uniformity index;

[0085] Step 122, according to the patch density, the maximum patch index, the edge density, the landscape shape index, the landscape spread index, the Shannon landscape diversity index and the Shannon landscape uniformity index, the landscape type, the number of patches or the total number of patches of the artificial river, the edge length of each landscape type patch, and the habitat type within the red line of the artificial river planning and construction;

[0086] Step 123, determining the landscape pattern by using Fragstats software according to the landscape pattern index.

[0087] In an embodiment of the present invention, by conducting a detailed investigation or survey of the construction target and calculating a series of landscape pattern indexes, the current status and potential characteristics of the artificial river landscape can be comprehensively and objectively evaluated; the calculation of landscape patches, landscape shapes and landscape diversity makes the analysis of the landscape more refined and can capture the subtle differences and changes in the landscape. Based on the landscape pattern index, the landscape type, number of patches and total number of patches within the red line of the artificial river can be accurately planned to ensure the scientificity and rationality of the landscape design. By optimizing the patch edge length and habitat type, the health and stability of the ecosystem can be promoted, biodiversity can be improved, and a sustainable landscape pattern can be constructed to meet the ecological and aesthetic needs of the long-term development of artificial rivers. Fragstats software is a professional landscape pattern analysis tool that can efficiently and accurately calculate and analyze the landscape pattern index. Based on the analysis results of Fragstats software, more scientific landscape planning and management decisions can be made to improve the overall benefits of artificial rivers.

[0088] In a specific embodiment of the present invention, after investigating or surveying the local natural river channel, the patch density, maximum patch index, edge density, landscape shape index, landscape spread index, Shannon landscape diversity index and Shannon landscape uniformity index of the natural river channel are calculated according to the following formulas. The artificial river channel landscape pattern index table is as follows:

[0089]

[0090] The patch density, maximum patch index, edge density, landscape shape index, landscape spread index, Shannon landscape diversity index and Shannon landscape evenness index of the natural river were calculated according to the formula to obtain the diversity index value. The diversity index value was then used as the background reference value. The landscape type, number of patches or the total number of patches of the artificial river within the red line of artificial river planning and construction, the edge length of patches of each landscape type, and the habitat type were determined based on the principle of being higher than the background reference value. The seven landscape pattern indices of the local natural river - patch density, maximum patch index, edge density, landscape shape index, landscape spread index, Shannon landscape diversity index and Shannon landscape evenness index - were investigated or surveyed, and the landscape pattern was determined using Fragstats software.

[0091] In a preferred embodiment of the present invention, the above step 121, investigating or surveying the construction target, calculating the landscape patches, landscape shapes and landscape diversity, includes:

[0092] Landscape patches include patch density and maximum patch index;

[0093] By PD=n i / A calculates the plaque density, where n i is the number of patches of the i-th landscape type or the total number of patches in the study area, A is the total area of ​​the region, and PD refers to the number of patches per hectare, which is used to describe the diversity of landscape types. The larger the PD, the higher the degree of spatial heterogeneity.

[0094] pass Calculate the maximum plaque index, where a ij is the maximum patch area of ​​the i-th landscape type or the largest patch area in the study area, A is the total area of ​​the region, and LPI is the maximum patch index, which is used to determine the proportion of the largest patch in the entire landscape.

[0095] In the present embodiment, patch density refers to the number of patches per hectare, which is used to describe the diversity of landscape types. The larger the PD, the higher the degree of spatial heterogeneity. The maximum patch index is used to determine the proportion of the largest patch in the entire landscape. It helps to determine the matrix or dominant type of the landscape, and its changes reflect the direction and intensity of human activities.

[0096] Patch density, as the number of patches per hectare, can intuitively depict the diversity of landscape types. The level of patch density affects ecological processes in the landscape, such as material circulation, energy flow, and information transmission. High patch density promotes interactions and gene exchanges between species, and enhances the stability and resilience of the ecosystem. In landscape planning, patch density can be used as an important reference indicator. By adjusting the patch density, the landscape structure can be optimized and the protection and development of ecological diversity can be promoted. Changes in patch density can reflect the dynamic changes in the landscape pattern. By regularly monitoring patch density, the changing trend of the landscape pattern can be understood in a timely manner, providing a scientific basis for landscape management and protection. The size and location of the largest patch affect the connectivity of the landscape. A large, continuous maximum patch may promote the migration and spread of species and enhance the ecological function of the landscape. In ecological protection, the largest patch is often the object that needs to be protected. By calculating the maximum patch index, key ecological areas in the landscape can be identified, providing a scientific basis for ecological protection.

[0097] In a preferred embodiment of the present invention, the above step 121, investigating or surveying the construction target, calculating the landscape patches, landscape shapes and landscape diversity, includes:

[0098] Landscape shape includes edge density and landscape shape index;

[0099] pass Calculate the edge density, where m is the total number of landscape element types at a certain spatial resolution within the study area, and p is ijis the length of the boundary between the i-th type of landscape patch and the adjacent j-th type of landscape element patch in the landscape, A is the total area of ​​the region, and ED is the edge density, which represents the edge length per unit area in the landscape;

[0100] By LSI=e i / min(e i ) Calculate the landscape shape index, e i is the total edge length of type i in the landscape, min(e i ) is the minimum edge length of landscape type i when the total area is constant and it is aggregated into a simple and compact landscape patch. LSI is the landscape shape index, which indicates the degree of aggregation of the landscape space.

[0101] In the embodiment of the present invention, edge density refers to the edge length per unit area in the landscape, reflecting the complexity of the landscape shape. The size of edge density directly affects the edge effect and species composition. The landscape shape index indicates the degree of aggregation of the landscape space, and can also indicate the complexity of the landscape shape.

[0102] Edge density provides a specific numerical indicator for quantifying the characteristics of landscape edges, which helps to more accurately understand the boundary conditions between different elements in the landscape. Edges are important areas for ecological interactions, such as species migration and energy flow. High edge density may mean more opportunities for ecological interactions, which has a positive impact on the stability and function of the ecosystem. Edge density can be used as an important reference indicator for landscape management. By adjusting the edge density, the landscape structure can be optimized, the protection and development of ecological diversity can be promoted, and the negative impact of edge effects can be reduced. Changes in edge density can reflect the dynamic changes in landscape pattern, especially the relative position and relationship between different landscape elements. By regularly monitoring edge density, the changing trend of landscape pattern can be understood in a timely manner, providing a scientific basis for landscape planning and adjustment. By calculating the landscape shape index, areas in the landscape that are too dispersed or too concentrated can be identified, thereby optimizing the landscape configuration and improving the aesthetic value and ecological function of the landscape. Compact landscape shape helps promote ecological connectivity, because shorter edge length means less resistance for species to migrate in the landscape. Therefore, by adjusting the landscape shape index, the ecological connectivity of the landscape can be enhanced. In landscape planning, the landscape shape index can be used as an important reference indicator. By considering the landscape shape index, a more reasonable, compact and eco-friendly landscape pattern can be designed.

[0103] In a preferred embodiment of the present invention, the above step 121, investigating or surveying the construction target, calculating the landscape patches, landscape shapes and landscape diversity, includes:

[0104] Landscape diversity includes landscape spread index, Shannon landscape diversity index and Shannon landscape evenness index;

[0105] pass Calculate the landscape spread index, where m is the total number of patch types, P i is the proportion of landscape area occupied by patch type i, g ik is the number of adjacent grid cells between patch types i and k, CONTAG is the landscape contagion index, which describes the degree of aggregation or extension trend of different patch types in the landscape;

[0106] pass Calculate the Shannon landscape diversity index, where p i is the area proportion of landscape type i in the landscape, m is the total number of landscape types, and SHDI is the Shannon landscape diversity index;

[0107] pass Calculate the Shannon landscape evenness index, where p i is the area proportion of landscape type i in the landscape, m is the total number of landscape types, and SHEI is the Shannon landscape evenness index.

[0108] In the embodiment of the present invention, the landscape spread index describes the degree of aggregation or extension trend of different patch types in the landscape. Generally speaking, a high spread value indicates that a certain dominant patch type in the landscape has formed good connectivity. The Shannon landscape diversity index is a sensitive indicator. For example, in a landscape system, the richer the habitat types, the higher the calculated SHDI value.

[0109] Through the landscape spread index, we can understand the spatial distribution characteristics of patch types in the landscape and judge whether they tend to be aggregated or dispersed. In landscape planning, the spread index can be used as an important reference to help plan a more natural and coherent landscape pattern and enhance the ecological connectivity and overall beauty of the landscape. By regularly calculating the landscape spread index, we can monitor the dynamic changes of the landscape pattern, timely discover the agglomeration or dispersion trend of patch types in the landscape, and provide a scientific basis for landscape management and protection. The higher the Shannon landscape diversity index, the more types there are in the landscape and the richer the diversity. The diversity index is closely related to the stability of the ecosystem. High diversity usually means that the ecosystem has higher resistance and resilience and can better cope with external interference. By calculating the Shannon landscape diversity index, we can identify areas with high diversity. The Shannon landscape uniformity index can evaluate whether the distribution of types in the landscape is uniform. The higher the index, the more uniform the distribution of types in the landscape, and there is no obvious dominant type. By calculating the uniformity index, we can identify areas with uneven distribution of types in the landscape, thereby optimizing the landscape configuration and improving the overall coordination and beauty of the landscape.

[0110] In a preferred embodiment of the present invention, the above step 13, based on the landscape pattern of the artificial river, with reference to landscape heterogeneity and ecological benefits, establishes an artificial river landscape pattern model, including:

[0111] Landscape heterogeneity includes longitudinal heterogeneity, lateral heterogeneity and vertical heterogeneity;

[0112] Ecological benefits include habitat function, filtering and barrier effects, and source-sink effects;

[0113] According to the landscape pattern, landscape heterogeneity and ecological benefits of artificial rivers, a landscape pattern model of artificial rivers is constructed.

[0114] In an embodiment of the present invention, by incorporating longitudinal heterogeneity, lateral heterogeneity and vertical heterogeneity into the artificial river landscape pattern model, the spatial structure and ecological characteristics of the artificial river can be more comprehensively reflected. Ecological benefit indicators such as habitat function, filtration and barrier effects, and source-sink effects are explicitly considered in the model, which helps to optimize the design of artificial rivers to maximize their ecological value. Through model-guided design, artificial rivers can better provide habitats for aquatic organisms, effectively filter pollutants, and serve as a source or sink of matter and energy in the ecosystem, thereby promoting the health and stability of the ecosystem. The artificial river landscape pattern model provides a scientific basis and guidance for the construction and transformation of artificial rivers.

[0115] In a preferred embodiment of the present invention, the above step 14, evaluating the changes of various landscape elements of the artificial river, includes: monitoring and collecting data for each type of landscape element to evaluate the changes of various landscape elements of the artificial river.

[0116] In a specific embodiment of the present invention, monitoring and data collection can accurately reflect the changes in the landscape elements of artificial rivers in real time, including water quality and flow of water bodies, stability and erosion of river banks, growth and coverage of vegetation, and use and aging of artificial facilities; based on detailed monitoring data, management decisions of artificial rivers can be made and adjusted more scientifically. Through continuous monitoring and data collection, possible anomalies or risks in the artificial river ecosystem can be discovered in a timely manner.

[0117] like Figure 2 As shown, an embodiment of the present invention further provides a system 20 for constructing an artificial river channel simulating a natural landscape pattern, comprising:

[0118] The planning module 21 is used to determine the objectives of the planned construction through fractal geometry theory. The objectives of the construction include the landscape type of the artificial river, the number of patches or the total number of patches of the artificial river, the edge length of each landscape type patch, and the habitat type;

[0119] Construction module 22 is used to calculate the landscape pattern index according to the construction objectives. The landscape pattern index includes landscape patches, landscape shapes and landscape diversity, and to determine the landscape pattern of the artificial river according to the landscape pattern index; to establish an artificial river landscape pattern model according to the landscape pattern of the artificial river, with reference to landscape heterogeneity and ecological benefits; and to evaluate the changes in various landscape elements of the artificial river.

[0120] In a specific example of the present invention:

[0121] First, in order to protect the landscape of forested land, cultivated land, and river islands, the fractal Brownian motion model is used in the river sections of these three types of land to simulate near-natural river channels with self-similarity and long-range correlation. In the simulation of river cross-sectional morphology, it can be used to generate shapes with natural textures and irregularities. The model controls the characteristics of the fractal through a parameter H (Hurst index), and the H value is between 0 and 1. The larger the H value, the smoother the surface, and vice versa. The steps include:

[0122] S1 determines the parameters of the model, including the Hurst exponent and the size range of the cross section (such as width and depth). For example, a Hurst exponent of 0.6 is selected, indicating that the generated cross section morphology is relatively smooth.

[0123] S2 uses a computer algorithm to generate a height field based on the FBM. This height field can be viewed as a two-dimensional matrix, where each element represents the height of a point in the cross section. By properly processing and visualizing this height field, the profile of the river cross section can be obtained.

[0124] S3 makes adjustments based on the generated contours in combination with actual engineering requirements and geological conditions. For example, if the geological conditions show that there is bedrock at the bottom of the river channel, then a corresponding flat area can be set in the generated contour to represent the bedrock part.

[0125] When simulating a river cross section in a mountain forest, a smaller Hurst exponent (such as 0.4) may be selected because the river in a mountain forest is greatly affected by the geological structure and water flow difference. In this way, the generated cross-sectional shape will be rougher, with more ups and downs and steep slopes, which is more in line with the complex terrain formed by natural river channels in mountain forests due to rock scouring and silt accumulation.

[0126] Next, based on the basic principles of fractal geometry, other types of land such as construction land and grassland are randomly generated under certain rules to construct shapes with fractal characteristics. When determining the cross-sectional morphology of the river channel, a fractal dimension (D) is first set to control the roughness or complexity of the cross-sectional morphology. For example, the fractal dimension is between 1 and 2. The larger the D value, the more complex the cross-sectional morphology. The steps include:

[0127] S4 sets initial conditions, including the approximate width and depth range of the cross section. For example, the maximum width of the river cross section is determined to be 10 meters and the maximum depth is 3 meters.

[0128] S5 generates a series of control points based on the selected fractal dimension using algorithms such as the random midpoint displacement method. Taking a simple one-dimensional case as an example, assuming that the contour line of the bottom of the river is to be generated, two endpoints are first determined at both ends of the cross section, and then the height of the midpoint between the two endpoints is determined according to certain random rules and fractal dimensions. The determination of this height usually takes into account the height difference of adjacent points and a random factor to increase the complexity of the morphology.

[0129] S6 repeats the above midpoint displacement steps for multiple times, gradually generating enough control points to depict the contour of the river bottom. For the two banks of the river, a similar method can also be used, but the operation is performed in the vertical direction to generate an irregular contour of the river bank.

[0130] Specifically, a river cross-section bottom profile with a fractal dimension of 1.5 is generated on the construction land. At the beginning, the length of the cross section is determined to be 20 meters, and the height of the two end points is 0 meters. After multiple midpoint displacement operations, an uneven bottom profile may be obtained, and there may be some local depressions and protrusions in the middle part. These shape features are similar to the complex terrain formed by the bottom of the natural river under long-term water scouring and sedimentation.

[0131] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for constructing an artificial river channel imitating a natural landscape pattern, characterized in that: The method comprises: Through fractal geometry theory, the objectives of the planned construction are determined, including the landscape type of the artificial river, the number of patches or the total number of patches of the artificial river, the edge length of each landscape type patch, and the habitat type; According to the construction objectives, the landscape pattern index is calculated. The landscape pattern index includes landscape patches, landscape shapes and landscape diversity. The landscape pattern of the artificial river is determined based on the landscape pattern index. According to the landscape pattern of artificial waterways, the landscape pattern model of artificial waterways is established with reference to landscape heterogeneity and ecological benefits; Assess changes in landscape elements of artificial waterways.

2. The method for constructing an artificial river channel simulating a natural landscape pattern according to claim 1, characterized in that: Through the theory of fractal geometry, the objectives of the planned construction are determined. The objectives include the landscape type of the artificial river, the number of patches or the total number of patches of the artificial river, the edge length of each landscape type patch, and the habitat type, including: Setting fractal parameters, wherein the fractal parameters include fractal dimension and curvature coefficient; According to the given fractal parameters, based on the iterative function system algorithm, a series of points are generated to determine the position of the river centerline; Adjust the generated river channel plan morphology according to the GIS data; Set a fractal parameter to describe the cross-sectional roughness; According to the fractal parameters, the profile of the river cross section is generated using a random fractal algorithm; According to the cross-sectional profile and cross-sectional morphology of the river channel, the aquatic habitat can be obtained; Adjust the curvature of the curved part of the river channel according to the simulation results of the computational fluid dynamics model, and plant aquatic plants in the slow-flow area formed at the bend of the river channel; In river bank design, the irregular river bank lines generated by fractal parameters are used to increase leisure facilities and landscape forest belts.

3. The method for constructing an artificial river channel simulating a natural landscape pattern according to claim 1, characterized in that: According to the construction objectives, the landscape pattern index is calculated. The landscape pattern index includes landscape patches, landscape shapes and landscape diversity. According to the landscape pattern index, the landscape pattern of the artificial river is determined, including: Conduct surveys or investigations on the construction objectives, and calculate landscape patches, landscape shapes, and landscape diversity. Landscape patches include patch density and maximum patch index, landscape shapes include edge density and landscape shape index, and landscape diversity includes landscape spread index, Shannon landscape diversity index, and Shannon landscape evenness index. According to the patch density, maximum patch index, edge density, landscape shape index, landscape spread index, Shannon landscape diversity index and Shannon landscape uniformity index, the landscape type, number of patches or the total number of patches of artificial waterways, the edge length of each landscape type and habitat type within the red line of artificial waterway planning and construction are determined; According to the landscape pattern index, the landscape pattern was determined by Fragstats software.

4. The method for constructing an artificial river channel simulating a natural landscape pattern according to claim 1, characterized in that: Conduct surveys or surveys of construction targets and calculate landscape patches, landscape shapes and landscape diversity, including: Landscape patches include patch density and maximum patch index; By PD=n i / A calculates the plaque density, where n i is the number of patches of the i-th landscape type or the total number of patches in the study area, A is the total area of ​​the region, and PD refers to the number of patches per hectare, which is used to describe the diversity of landscape types. The larger the PD, the higher the degree of spatial heterogeneity. pass Calculate the maximum plaque index, where a ij is the maximum patch area of ​​the i-th landscape type or the largest patch area in the study area, A is the total area of ​​the region, and LPI is the maximum patch index, which is used to determine the proportion of the largest patch in the entire landscape.

5. The method for constructing an artificial river channel simulating a natural landscape pattern according to claim 1, characterized in that: Conduct surveys or surveys of construction targets and calculate landscape patches, landscape shapes and landscape diversity, including: Landscape shape includes edge density and landscape shape index; pass Calculate the edge density, where m is the total number of landscape element types at a certain spatial resolution within the study area, and p is ij is the length of the boundary between the i-th type of landscape patch and the adjacent j-th type of landscape element patch in the landscape, A is the total area of ​​the region, and ED is the edge density, which represents the edge length per unit area in the landscape; By LSI=e i / min(e i ) Calculate the landscape shape index, e i is the total edge length of type i in the landscape, min(e i ) is the minimum edge length of landscape type i when the total area is constant and it is aggregated into a simple and compact landscape patch. LSI is the landscape shape index, which indicates the degree of aggregation of the landscape space.

6. The method for constructing an artificial river channel simulating a natural landscape pattern according to claim 1, characterized in that: Conduct surveys or surveys of construction targets and calculate landscape patches, landscape shapes and landscape diversity, including: Landscape diversity includes landscape spread index, Shannon landscape diversity index and Shannon landscape evenness index; pass Calculate the landscape spread index, where m is the total number of patch types, P i is the proportion of landscape area occupied by patch type i, g ik is the number of adjacent grid cells between patch types i and k, CONTAG is the landscape contagion index, which describes the degree of aggregation or extension trend of different patch types in the landscape; pass Calculate the Shannon landscape diversity index, where p i is the area proportion of landscape type i in the landscape, m is the total number of landscape types, and SHDI is the Shannon landscape diversity index; pass Calculate the Shannon landscape evenness index, where p i is the area proportion of landscape type i in the landscape, m is the total number of landscape types, and SHEI is the Shannon landscape evenness index.

7. The method for constructing an artificial river channel simulating a natural landscape pattern according to claim 2, characterized in that: According to the landscape pattern of artificial rivers, with reference to landscape heterogeneity and ecological benefits, an artificial river landscape pattern model is established, including: Landscape heterogeneity includes longitudinal heterogeneity, lateral heterogeneity and vertical heterogeneity; Ecological benefits include habitat function, filtering and barrier effects, and source-sink effects; According to the landscape pattern, landscape heterogeneity and ecological benefits of artificial rivers, a landscape pattern model of artificial rivers is constructed.

8. A system for constructing an artificial river channel imitating a natural landscape pattern, characterized in that: include: The planning module is used to determine the objectives of the planned construction through fractal geometry theory. The objectives of the construction include the landscape type of the artificial river, the number of patches or the total number of patches of the artificial river, the edge length of each landscape type patch, and the habitat type; The construction module is used to calculate the landscape pattern index according to the construction objectives. The landscape pattern index includes landscape patches, landscape shapes and landscape diversity, and to determine the landscape pattern of the artificial river based on the landscape pattern index; to establish an artificial river landscape pattern model based on the landscape pattern of the artificial river and with reference to landscape heterogeneity and ecological benefits; and to evaluate the changes in various landscape elements of the artificial river.

9. A computing device, characterized in that include: one or more processors; A storage device for storing one or more programs, when the one or more programs are executed by the one or more processors, the one or more processors implement the method as claimed in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a program, which, when executed by a processor, implements the method according to any one of claims 1 to 7.

Images