Study On City Greenspace Ecological Network Based On RS And GIS

Along with the process of urbanization, the development of natural and the reconstruction strengthen the changes in the city pattern. Habitat fragmentation and habitat loss are widely recognized as major threats to biodiversity & extinction on a global scale. The main reason is that it may cause the reduction of the number of species and mortality and reduce species possibility of reproduction in other habitat. Urban areas can contain rich flora that contribute significantly to biodiversity.Urban greenspace ecological networks in study area weaken the fragmentation of urban greenspace patch, enhance the ecological function, improve the connection of ecological function network, promote the urban ecosystem function and value, and restrict urban pattern's spread, and help protect the relative significance of each greenspace and guide urban planning.The paper reviews and summarizes quantities of related studies and experiences. On the basis of that, constructs a multipurpose research approach of the urban greenspace ecological network. Under the support of RS and GIS, Potential green corridors were identified in Yangzhou City using the least-cost path method, and ecological networks were developed and improved based on the gravity model and landscape connect index. Analysis of spatial patterns revealed that the proposed plan decreased the degree of fragmentation and increased connectivity.The main studying of this paper are the followings:(1) Two TM images, which are fused and transformed, are optimized by OIF; and then extract better information on urban greenspace with the decision tree of QUEST algorithm. The Kappa is 0.88.and the user accuracy of urban greenspace is 97.01%(2) Compared to traditional Connectivity indicators, using CONEFOR SENSINODE 2.2 software analyzes the importance of connectivity of Green patches in study area. dLCP, dIIC and dPC to more accurately indicate the level of connectivity of urban green space patches.(3) Using AHP method to construct the cost surface can effectively solve the problems of identifying resistance value in the model. This paper introduces AHP method to determine the resistance weight, and According to the actual investigation in study area, we modify resistance value in Landscape of high resistance area and unconnected region. This method integrates the theoretical knowledge and practical experience of experts in various fields.(4) Least-cost distance model more successfully solves how to build green corridor of protecting target species between sources and targets. This paper adopts least-cost distance model method builds potential green corridor in YangZhou's network system, forms a scientific and reasonable green ecological network, and introduces network coverage and network green ratio to assess greenspace spatial distribution...