Research On Ecological Network Based On Green Infrastructure Evaluation Model

Ecological network can solve the problems such as habitat fragmentation caused by the rapid urbanization process,and is an effective way to ensure urban ecological security and promote the green transformation of urbanization.Under the background of limited land resource supply and equal emphasis on resource protection and development coordination,how to build a priority and multi-functional ecological network is particularly important to control and guide the sustainable development of cities.Green infrastructure evaluation model as a kind of fully consider the necessity of ecological construction and social economic reality of green infrastructure planning method,the core technology means is the identification and evaluation of network space elements,it can quickly identify and evaluate the priority protection of land resources for ecological network construction has practical reference significance.County bears the "pattern,lead" the important role,is the key level of national ecological space restoration,fangcheng county as Nanyang northern portal city and cattle area ecological protection important growth pole,with good ecological environment and diversified natural and human resources,tap these resources value can make the social economic sustainable development and people’s better life component,so it is necessary to explore an ecological environment and urban and rural development of ecological network research mode.Based on this,in this study,taking the ecological network as the research object and Fangcheng County of Henan Province as an example,the relatively mature green infrastructure evaluation model was introduced to study the ecological network in the research area.The paper first explains the basic research background,research significance,concept and theory,discusses the relationship between the green infrastructure evaluation model and ecological network.Then identify and evaluate the ecological sources and nodes of the research background,research significance,concept and model.Then,the ecological importance evaluation index system,gravity model and landscape connectivity index can classify the extracted ecological sources,ecological corridors and ecological nodes successively.Finally,the ecological network pattern optimization and the specific development and protection strategies for the network elements of different importance levels are put forward to provide some reference for the future ecological network research.This paper mainly draws the following conclusions:(1)From the perspective of ecological network element identification.A total of 34 ecological sources,98 ecological corridors and 141 ecological nodes were identified in the study area.Among them,the ecological sources mainly gather in Silidian Township,Guaihe Town and Yangji Township in the north of the county.The ecological sources in the east and west are scattered and linear.In the central region lack large ecological sources due to the distribution of construction land and cultivated land.Mountains and large reservoirs are the main components of ecological sources,while other ecological sources are composed of grassland and woodland.Ecological corridor in the northern ecological area more dense distribution,connecting between east and south and north ecological corridor inevitable through the human activities of cultivated land and urban edge,with the expansion of the city these corridors may be further threatened,forest land and cultivated land is the main elements of ecological corridor.The ecological node is located at the corridor intersection and the corridor is crossed by the main traffic trunk line.(2)From the importance evaluation of ecological network elements.The importance of ecological source in Fangcheng County presents a trend of high from north to south and low from east to west.The importance level of ecological sources is assigned from high to low to 5,4,3,2,1 respectively,among which only 5 are above 3,while the remaining 29 ecological sources are below 3,indicating that the overall evaluation level of ecological sources in the county is low.The importance of ecological corridors is divided into very important corridors,important corridors and general corridors,with 12 corridors,27 corridors and 59 corridors,respectively.Very important corridors are mainly distributed between close patches,and important corridors are manifested between close and large core patches.These two grades of corridor species pass through fewer types of resistance and play a key role in the whole network system.However,there are many types of landscape resistance between the distant patches,and the species are not easy to cross,so the corridor level is low.Among the ecological nodes,there are 11 rated as important nodes,namely,7 ecological nodes with the highest landscape connectivity index,1 ecological node at the intersection of very important corridors and important corridors,and 2 ecological nodes where very important corridors are crossed by railway.Other ecological nodes serve as general ecological nodes.(3)From the perspective of ecological network pattern optimization and protection strategy.Network pattern optimization mainly through large ecological source and central region add stepping stone to extend the original ecological source area,strengthen the north and south and east and west ecological flow exchange,but also through the integration of current traffic,river corridor of ecological corridor system,the potential corridor and current corridor designated appropriate corridor width.The protection strategy is mainly formulated from three aspects: dividing the priority protection level of the ecological network,mining the compound multi-functional value,promoting multi-department cooperation and public participation.