| At present,China is experiencing a rapid urbanization process.Agricultural population continues to transfer to the city,and the number and scale of the city are in constant growth and expansion,but also a series of urban ecological environment problems appear.The decline of overall ecological function and ecological deterioration has become an obstacle to human survival and social sustainable development.The landscape ecological pattern can reflect the ecological process of the regional landscape,and the different landscape ecological pattern has the uncertainty of improving the ecological environment or degrading the ecological environment.Irrational landscape ecological pattern will lead to such as environmental pollution,climate warming,urban floods and many other problems.Based on the theory of "patch-corridor-matrix" of landscape ecology,the ecological source,ecological corridor,ecological node and ecological matrix of the study area were identified scientifically,and the urban ecological land network space was constructed.Based on this,it is an effective way to optimize the ecological pattern of urban landscape,realize the regulation and improvement of urban ecological environment,and enhance the continuity and integrity of ecological environment function.It is a new and promising research direction to study the optimization of landscape pattern from ecological process.However,the current research in this area has a certain degree of difficulty and lack of reliable means of research.In the face of the high connectivity of urban construction land and the low spatial connectivity of ecological land network space,the planning of urban landscape ecological pattern,which aims at enhancing the urban ecological land use,is an effective complement to traditional urban ecological planning.It aims to complete the analysis and evaluation of urban ecological land network,and construct the ecological landscape pattern of urban landscape with ecological function integrity and ecological land network connectivity.This paper takes Xinbei District of Changzhou City as the research area,carries on the spatial analysis and the appraisal to the urban ecological land network.On this basis,the spatial pattern of "ecological source-ecological corridor-ecological node-ecological matrix",which constitute the urban ecological land network,is optimized to make up the status quo of the ecological land network.Based on the theory of"patch-corridor-matrix" of landscape ecology,the ecological source,ecological corridor,ecological node and ecological matrix of the study area were identified by quantitative and qualitative analysis method.Build the urban ecological land network space,analyze the spatial distribution of urban ecological land network spatial connectivity degree,and then find out the optimization focus.Ecological land network-ecology node-ecological matrix in the study area was optimized,and the landscape ecological pattern optimization based on the ecological land network elements was realized by GIS technology and CA-Marcov model.To construct the ideal landscape ecological pattern with ecological land network connectivity and ecological function integrity,and to improve the functional connectivity and the structural connectivity of the urban landscape ecological system.Strengthen the spatial connection between ecological source,ecological corridor and ecological node,so as to maintain the stable development of landscape ecological pattern.The research results can provide scientific basis and theoretical guidance for small and medium scale ecological environment protection and urban planning.The main contents and results are as follows:(1)Spatial identification and construction of urban ecological land network Firstly,the regional ecological suitability was partitioned by the minimum cumulative resistance model,and the other components of the ecological security pattern were determined on the land use suitability zoning map.Identification of ecological sources by selecting the area in line with the requirements of forest,water,beach and scenic areas.The recognition of ecological corridor is based on the selection of vegetation index(NDVI),water body index(MNDWI)and building index(NDBI)to establish the forest species,and then the shortest path method is used to extract the ecological corridor.And then extract the intersection of ecological corridor as the key ecological node.And finally build the ecological land network system of Xinbei District of Changzhou City.The results showed that the eco-matrix was divided into prohibited development zone,restricted development zone,ecological coordination zone and guided construction area.The ecological sources are divided into four types,which are forest ecological source,aquatic ecological source,tidal ecological source and scenic ecological source.The southeast,southwest and middle of the study area are few in number and small in area,showing isolated distribution.Ecological corridor a total of 45.There are 23 key ecological nodes,mainly in the north of the study area.(2)Urban ecological land network space evaluation and classificationFirst,the size and spatial distribution of each ecological source shape index,the size and spatial distribution of ecological sources and ecological nodes were analyzed.The y,a and B indices of each landscape ecological land network in the study area were calculated and used as different ecological corridor attributes value.The indices of each corridor are added with the same weight to get the composite index.The comprehensive index is used to express the connection degree of ecological corridor in the study area.Then the ecological sources,ecological corridors and ecological nodes were classified according to the evaluation results of the connectivity.Finally,the transfer matrix and the dynamic evaluation model of ecological land use are used to analyze the distribution of land use and transfer,and the range and velocity characteristics of ecological land use.The evaluation results show that the shapes of various ecological sources are simplified,and the contact area with other types of land edge is small,and the contact with other materials is poor.There are many ecological corridors in the waters and scenic areas,and there are not many ecological corridors in the forest land,shoal and most ecological nodes.The connectivity of ecological corridor in the south and north of the study area is weak.The ecological corridor connectivity in the south part of the central part is at the middle level,and the existing ecological corridor in the north part of the middle part is better.Ecological corridors and ecological nodes are divided into three levels.The ecological connectivity and ecological connectivity of ecological corridors,ecological corridors and ecological nodes are high,and ecological functions are dominant.The spatial connectivity of secondary ecological sources,ecological corridors and ecological nodes needs to be further optimized.In 2005-2014,a large area of ecological land was converted to agricultural land,and ecological land occupation was serious.The fragmentation layout was not conducive to the flow of material and energy in urban ecosystem.(3)Urban ecological land network space optimization and promotionFirstly,the functional connectivity degree of ecological source is optimized,which is divided into two types:small-scale and large-scale ecological source.The ecological sources are divided into buffer zones with different distances,and the most ideal scheme was selected to optimize the structural connectivity of the ecological source.Then,according to the result of ecological corridor space evaluation,the functional connectivity degree of ecological corridor is optimized,which is divided into small and large ecological corridor.The ecological corridor is divided into buffer zones with different distances,and the optimal scheme is chosen to optimize the structural connectivity of the ecological corridor.And then use the blind area analysis method for ecological node optimization,delineation of short-term,medium and long-term ecological node optimization area.Finally,the CA-Markov model was used to optimize the ecological matrix,and the Kappa coefficient was checked by the IDRISI platform to reserve a certain amount of land for the future development of the ecological source area.The results showed that the ecological patches were supplemented by small patch and the large patch,which played a role in the urban ecological landscape.When ecological buffer zone was set at 1000m,the correlation degree with other ecological patch was the best.According to the results of ecological corridor spatial assessment,large and small ecological corridors are constructed,and the buffer distance of 400 meters is set for ecological corridor to enhance the ecological effect of large ecological corridors and stabilize the long-term development of small ecological corridors.Through the identification of ecological blind spots to improve the ecological node construction.In the eco-matrix optimization,the area of ecological land increased compared with the land area of various types of matrices in 2014,and most of the new ecological land was transferred from the surrounding agricultural land matrix. |
PDF Full Text Request