我国设区市绿化覆盖率与绿地率区域耦合差异分析——基于干湿气候区划的视角

绿化覆盖率和绿地率是衡量我国城市绿化发展水平的重要指标，长期以来我国都采用城市建成区绿化覆盖率比与绿地率高5%的经验数值来预测绿化覆盖率的大小，但随着我国城市绿化事业的快速发展，5%的差值与城市绿地实际发展水平越来越不相符。为此，基于绿化覆盖率与绿地率之间特有的耦合关系，以281个设区市为样本，探究1999-2017年基于不同干湿气候区划下城市建成区绿化覆盖率与绿地率耦合差值状况。结果表明:1）不同干湿区划内的城市两指标都呈现出了协同性的增长趋势，表明我国城市的绿化水平都在同步提高。但不同干湿区划间两指标的平均差值各不相同:湿润地区是3.73%、半湿润地区是4.70%、半干旱地区是3.13%、干旱地区是3.33%；2）各干湿区内城市绿化覆盖率与绿地率平均差值的标准差分别为湿润区0.19、半湿润区0.57、半干旱区0.88、干旱区0.78，这表明4大干湿区划内城市2指标平均差值的离散程度为半干旱区＞干旱区＞半湿润区＞湿润区。通过分析近20 a来我国城市绿化覆盖率与绿地率耦合平均差值，以期为我国各地城市预测绿化覆盖率提供参考。

Regional Coupling Differences of Green Coverage Rate and Green Space Rate of the Cities with Districts in China——A Perspective Based on Dry and Wet Climate Zoning

Green space ratio and green coverage rate are important indicators to measure the level of urban greening development in China.For a long time,China has used the experience value of urban green coverage rate ratio by 5% higher than the green space rate to predict the green coverage rate.However,with the rapid development of urban greening in China,the difference of 5% is more and more inconsistent with the actual development level of urban green space.Therefore,based on the specific coupling relationship between green space rate and green coverage rate,this paper used 281 cities with districts as samples to explore the coupling difference between urban green space rate and green coverage rate based on different wet and dry climate zones from 1999 to 2017.The results showed that 1) two indexes in different wet and dry zones showed a synergistic growth trend,indicating that the greening levels of all cities in China increased simultaneously.However,their quantitative values of the mean difference of two indices were significantly different between dry and wet areas:they were 3.73%,4.70%,3.13%,and 3.33%,respectively in humid,semi-humid,semi-arid,and arid areas.2) The standard deviations of the average difference between two indices in the areas mentioned above were 0.19,0.57,0.88,and 0.78,respectively,indicating that the degrees of dispersion of the average difference between the two indices were in the order of semi-arid area> arid area> semi-humid area>humid area.By analyzing the average difference between the urban green coverage rate and the green space rate in China in the past 20 years,the results of this study can provide a reasonable reference for predicting the green coverage rate in different cities in China.