Comprehensive Evaluation And Improvement Design Of Street Greening Quality In Tianfu New District Of Chengdu

With the proposal of the concept of park city construction and the establishment of evaluation standards,attention has been paid to the improvement of urban environmental quality.As an important part of the urban environment,the evaluation and improvement of the green quality of the street has become the priority among priorities.Early studies on street greening quality mainly focused on subjective evaluation.Later,with the continuous progress of science and technology,green coverage rate and green vision rate have gradually become important indicators to evaluate street greening quality.They describe multiple characteristics of street greening quality from different dimensions,but a single index cannot comprehensively evaluate the real level of street greening quality.Therefore,in this paper,multiple dimensional evaluation indexes are integrated and AHP is adopted to build a comprehensive evaluation system for street greening quality.Taking street greening in Tianfu New District of Chengdu as the research object,remote sensing interpretation,image semantic segmentation,questionnaire survey and other methods are adopted according to satellite remote sensing maps and street images.The street greening quality of Tianfu New District was evaluated qualitatively and quantitatively from three dimensions: macro remote sensing,micro street view and subjective perception,and the evaluation results were divided into five levels for detailed analysis.Specific research conclusions are as follows:(1)The comprehensive evaluation model of street greening quality in Tianfu New District was established.It includes three criterion layers: macro remote sensing dimension,micro street view dimension,subjective perception dimension,nine index layers green coverage rate,green vision rate,green species,etc.,and calculates the corresponding weight value.(2)Street greening in Tianfu New District was evaluated in different dimensions,and Arc GIS and Yaahp were used to visualize and analyze the correlation of data results.In Tianfu New District,the street green coverage rate,green vision rate and subjective evaluation score are different in the overall distribution,the distribution of different administrative divisions and the distribution of different street levels.And the data showed that there was a significant correlation among green coverage rate,green vision rate and subjective evaluation,showing a significance level of 0.01.(3)The evaluation data of the three dimensions were substituted into the comprehensive evaluation model of street greening.In the comprehensive evaluation of street greening in Tianfu New District,the number of streets with very low,low,average,high and very high greening quality were 33,209,396,142 and 0,respectively.From the perspective of administrative division,the comprehensive quality of street greening in each area is Wan ’an Street > Zhengxing Street > Xinglong Street > Huayang Street,and the comprehensive quality of street greening of different levels is branch road > secondary trunk road > express road > main road.(4)Finally,this paper conducted an in-depth investigation on the greening of 33 streets at a very low level and 209 streets at a low level,found typical problems,and put forward targeted transformation and improvement strategies,and made transformation and improvement designs for some street greening.