Study On Green Space Layout Of Chixi Town Based On Ecological Suitability Evaluation

China is in a critical window period of rapid urbanization.People's material and cultural life has been greatly improved,and they have a higher level of pursuit for urban green space,but it is affected and restricted by more and more factors,such as unbalanced layout,insufficient accessibility,lack of publicity and interaction.The function of urban green space is directly affected by the spatial layout structure.In view of the current urban green space system planning mainly relies on perceptual and empirical methods,this paper hopes to build a comprehensive evaluation system of urban green space layout rationality with the help of scientific and effective analysis methods,and put forward specific and feasible targeted suggestions to constantly improve the spatial layout of green space.The suitability analysis of urban green space is the premise for planners to make scientific decision.This paper takes FRAGSTATS and GIS as the main technical support and Chixi town in Cangnan County as the research object,and adopts the research method of field investigation to obtain the green space information of the research area from the remote sensing image.Firstly,the landscape pattern of Chixi town is analyzed.Using the method of multi factor evaluation,the paper selects six most representative evaluation factors of green land suitability analysis,constructs AHP(analytic hierarchy process)and fr(frequency ratio)model,analyzes the ecological suitability of Chixi Town,and tests and optimizes the two methods combined with ROC curve,and systematically studies the actual spatial distribution of green land patches in Chixi town.Combined with the relevant theory,the optimal plan of urban green space layout and the most suitable area for construction is obtained.The results show that:(1)The factors selected in this study are: elevation,water distribution,road distribution,land use,ancient and famous trees and vegetation index.The area under ROC curve calculated by AHP model and FR model is 0.768 and 0.823 respectively,and the sensitivity of FR model is higher than that of AHP model;according to FR model analysis,high suitable area is mainly distributed in the West and north of Chixi Town,and unsuitable area is mainly distributed in the east coastal area;according to area statistics,high suitable area accounts for 21.12% of the total area,and unsuitable area accounts for the total area.4.9% of the product.By comparing the two ecological suitability models,we can effectively analyze the advantages and disadvantages of the model and provide reference for the optimization of the model.(2)According to the high suitability and low suitability green patches obtained from FR model,the landscape pattern analysis shows that the high suitability green patches have the characteristics of low heterogeneity,less human interference,more large patches,high patch aggregation and low fragmentation;the low suitability green patches have the characteristics of serious human interference,lack of large patches and low patch aggregation.And the high degree of fragmentation further verified the analysis results of the current situation of green space in Chixi town.(3)So far,based on the above results of landscape pattern analysis of green patches with different ecological suitability,combined with the traffic corridor and river system in the region,the green space layout with the structure of "one center,three streams,five roads and five points" is determined in the scope of the town,and the targeted and feasible green space system layout of Chixi town is proposed from the macro,medium and micro levels Sexual planning suggestions.