Study On Landscape Pattern Evolution And Potential Ecological Risk Assessment In Huzhou

Huzhou municipal district area is located in the northern part of Zhejiang Province,is located at the junction of Tianmu Mountain and Hangjiahu Plain,since the urbanization process in 2010 has been accelerated,landscape patterns and ecological environment have undergone some changes.Huzhou was named the first batch of ecological civilization demonstration area in 2014,through quantitative analysis of its construction of ecological civilization demonstration area before and after the different periods of landscape pattern characteristics,is conducive to reflect the changes in its ecological environment for the late ecological environment protection,Management,ecological risk avoidance has a significant role and significance,but the relevant research is almost blank.Based on RS and GIS techniques,the Landsat image data of Huzhou municipal district area in 2010 and 2015 were extracted by visual interpretation method.The landscape pattern was analyzed by landscape pattern index calculation,land use dynamic degree and transfer matrix.The ecological risk assessment model was constructed by selecting the landscape pattern index,and the temporal and spatial distribution characteristics of local ecological risk were analyzed.Finally,combined with the landscape pattern analysis and ecological risk assessment for the future ecological civilization construction put forward reasonable countermeasures and suggestions.The main results are as follows:(1)Analysis of Land Use Structure and Pattern Change.The results show that the natural landscape and mining land have declined in 5 years,and the cultural landscape such as pond and construction land have risen.The change rate of each landscape type is as follows: Town and the following settlements> Urban construction land> Garden> Cultivated land> Pond water surface> Natural waters> Forest land> Other construction land> Mining land,frequent transfer between various types of land Poor stability.(2)Analysis of Landscape Pattern and Evolution.The landscape pattern and landscape characteristics were calculated by the landscape pattern index.From the overall landscape level analysis,landscape fragmentation,connectivity,separation has declined,the shape tends to be complicated.At the same time because of the impact of human activities,the overall landscape pattern was diversified,the role of some of the advantages of plaque weakened.From the plaque type analysis,the cultivated land fragmentation deepened,the dominance weakened,the shape was more complicated,but still the dominant landscape in the area.The greater the impact of policy,such as garden landscape dominance significantly improved,the town and the following settlements the most rapid development,landscape dominance,a substantial increase in the degree of polymerization.(3)Study on the Driving Mechanism of Landscape Pattern.The results show that most of the cultivated land,water pits and urban and rural construction land will be distributed at lower altitudes and smaller slopes,but the cultivated land will be distributed from the perspective of altitude and slope,traffic,population and so on.The park and the town and the following names have a higher elevation and elevation of the trend.In the administrative center,the main distribution is the urban and rural construction land,cultivated land;the traffic route of China Road on the landscape distribution of the most obvious;urbanization caused by the increase in non-agricultural population is an important reason for the reduction of arable land,Such as green mine policy to reduce the area of mining area.(4)Landscape Ecological Risk Assessment.Through the construction of the landscape ecological risk assessment model and the calculation and interpolation,the results show that the ecological risk of landscape is decreasing from 2010 to 2015,the area of high risk area is obviously reduced and the area of low risk area is increasing.2010 risk distribution was east high west low,from west to east were medium-higher-high distribution.To 2015 is mainly medium risk,the western mainly low risk and lower risk zone,the central and western regions for the higher risk zone.The higher risk areas are mainly located in the plains of the river network,and the risk value of urban built-up areas and western forest land is not high.In general,the ecological risk of landscape ecology is declining in the past 5 years,and the high-risk area is still located in the plain area where human activity is frequent.According to the results,it can be seen that the landscape pattern and ecosystem of Huzhou municipal district are obviously changed.Based on the analysis and evaluation of landscape pattern and ecological risk in Huzhou municipal district area,this study can grasp the characteristics and laws of time and space change more accurately.And then for the future Huzhou municipal district area of ecological management,development and protection to provide a reference.And put forward the rationalization proposal which is beneficial to the protection of the local ecological environment,and provide scientific management basis for the rational development of the measures so that these measures conform to the concept of scientific development concept and meet the requirements of ecological civilization construction.