Study On Landscape Pattern Optimization Based On Ecological Vulnerability Analysis In Qionghai

Landscape pattern optimization has been one of the key issues in landscape ecology research,which is of great significance to the maintenance of regional ecological security and sustainable development.This paper based on vulnerability analysis of ecological environment in Qionghai City,selected ecological source scientifically,build a comprehensive ecological resistance surface,extraction of ecological corridor and ecological nodes,study the optimization of landscape pattern of Qionghai City,and put forward some corresponding suggestions,so as to Qionghai city to optimize landscape pattern to provide a scientific basis and theoretical reference.the conclusions are as follows:(1)Using ArcGIS10.2 and other software,using particle size analysis,incremental spatial autocorrelation and other models,through the selected patch density(PD),Shannon index(SHDI)and other indicators,analysis of the suitability of Qionghai landscape granularity and amplitude analysis.The results show that when the landscape suitability analysis granularity is 180m,the combination of landscape patches is the best,and the spatial clustering effect is more significant when the landscape suitability analysis is 4140m.(2)By selecting 6 ecological sensitivity factors,such as elevation,slope,and 7 landscape pattern measurement factor,such as patch density(PD)and index(AI),we constructed a comprehensive evaluation system of eco-environmental vulnerability in Qionghai.ArcGIS10.2 was used to classify each index factor,and the spatial principal component analysis was used to determine the weight of each index factor.The weight values of each factor were classified as canopy density>soil type>age group>land type>slope>elevation.It can be seen that the elevation of the ecological sensitivity of the smallest impact on Qionghai,the highest is canopy density.The weighting values of each factor of ecological vulnerability are:adjacency ratio>connectivity>average neighborhood index>cohesion index>sensitivity index>patch density>aggregation degree>separation degree.It can be seen that the adjacency ratio has the greatest impact on the ecological environment vulnerability of Qionghai,and the separation index has the least influence.(3)Using ArcGIS10.2 spatial analysis tools,the ecological sensitivity factors were weighted and re-classified.By using the natural fracture method to determine the sensitivity classification standard,the distribution of ecological environmental sensitivity in Qionghai city was obtained.It can be seen that the spatial distribution of ecological sensitivity in Qionghai is generally in the middle,Middle East,South-east,north-east,north-west,West,South and south-west.Compared with the spatial distribution of the factors,it can be found that the spatial distribution of ecological sensitivity in Qionghai has a great relationship with the canopy density,which is related to the soil type,age group and cover type.(4)Using ArcGIS10.2 spatial analysis tools of various ecological factors are fragile and weighted superposition of classification interpolation using ordinary Kriging interpolation method,and the method for determining the vulnerability of natural fracture classification standard based on ecological environment in Qionghai city that the level of vulnerability distribution map can be seen:the grade of micro fragile zone,Ⅱ grade Ⅲmild fragile area and moderate fragile area accounts for the total area of Qionghai city in 72.21%,grade of severe fragile area and V-grade fragile area accounts for 27.79%,indicating that the current overall situation of ecological environment in Qionghai city.The spatial distribution shows the eastern,northeastern and northwestern lower south,Southeast the distribution trend,southwest and North high.Among them,grade Ⅱ micro fragile area and mild fragile areas,mainly distributed in the eastern city of Qionghai,in the northwest,supporting suggestions in the rational use of the water protection area,fully Play the role of regulating water ecological environment,and rational planning of land use,strengthening ecological construction;grade moderate vulnerable area accounted for the most,up to 30.66%,and mainly located in the Midwest and northeast of a narrow band,reasonable planning of modern agriculture and forestry industry in the region,set the corresponding transition zone and north of a small mountain.Part IV severe fragile area and V-grade fragile areas are mainly located in the southwest of the city of Qionghai,proposed to strengthen the ecological construction in the region,mainly to protect the development of secondary setting,human activities prohibited area and restricted area,maintain the native state of the natural environment.(5)The city of Qionghai were selected with 31 ecological source set requirements,the total area is 63736.08 hm2,the total area of Qionghai city 37.24%.which is mainly distributed in the west,southwest and northwest,showing the overall dispersion characteristics of partial accumulation.Among them,the southwest ecological source of large scale,wide area;middle east.The southeast and northeast ecological source is smaller,less area.The southwest ecological construction of key source protection suggestions,and take the buffer zones to strengthen measures to promote ecological service functions.Colleagues in the eastern city planning and construction,should rationally adjust the land use structure,part of the new ecological sources,and strengthen the protection of the source,improve the ecological and ecological corridor construction,make the ecological system effective movement.(6)The ecological corridor of Qionghai City,a total of 73,mostly located in the northeast of Qionghai City,respectively in 4 and 4 in the fragile area of cover types inside.According to the ecological environment vulnerability classification:class Ⅰ micro fragile zone,grade Ⅱ and grade Ⅲ fragile area mild moderate vulnerable area distribution is more,respectively 22,25 and 19;Ⅳ severe fragile area distribution less,7;Ⅴ extremely fragile areas is 0.According to cover types:forest ecological corridor,36;garden ecological corridor of 19;then the waters of ecological corridor,13;farmland ecological corridor at least 5.Preferred to focus on the construction of forest ecological corridor,to delineate the enclosure with the way to realize the ecological environment self repair and upgrading.Key construction for farmland ecological corridor should be anti pollution ability for garden species.Ecological corridors should be designated construction scope,Tim With the appropriate native plants.Due to construction of ecological corridor is linear or zonal space form,local high vulnerability,suitable buffer zone is arranged around the ecological corridor,to protect the ecological function of ecological corridor play normal.(7)The ecological node of Qionghai city a total of 50,mainly distributed in the northeast of Qionghai City,were distributed in 5 fragile ecological environment area and 4 cover types.According to ecological environment vulnerability classification:Class Ⅱslightly vulnerable areas most V-grade fragile area at least,from grade to grade Ⅴrespectively.As of 16,20,9,4,1.According to the cover types:Forest Ecological nodes up to 28,garden 10,9 water,arable land at least,only 3.Focus on the proposed construction of ecological forest node,set the corresponding buffer zone,reduce man-made interference,pollution into the barrier the rich biological diversity,enhanced connectivity and mobility between the ecological corridor,give full play to the ecological benefits of forests and woodlands.Garden in nature,in the foundation of ecological forest construction measures on the node,but also the reasonable collocation of planting vegetation,prevent soil erosion,improve the economy Benefit and give full play to the ecological benefits of forest garden.We should strengthen the ecological node construction,setting up the corresponding isolation zone,water source protection,strengthen circulation,give full play to the regulating role.Finally,to strengthen the waters for construction of ecological node construction,reasonable planting cover and low shrubs,optimizing the urban surrounding ecological corridor together,realize the harmony between man and nature and sustainable development.