基于绿视率的武汉市绿地公平性评价

Equity evaluation of urban green space in the main urban area of Wuhan based on green view index

绿地是一种资源福祉,基于绿视率的绿地公平性评价对保证绿色资源的公平分配具有重要意义。以武汉市中心城区为研究对象,基于百度街景地图、百度热力图、卫星遥感影像等多源数据,利用区位熵、基尼系数以及洛伦兹曲线,对武汉市绿视率空间分布公平性进行评价。结果表明:武汉市中心城区绿视率水平在较差以下的点位数量共占87.6%,主要集中在青山区武汉钢铁工业基地以及严东湖以南;达到很好水平的点位数量最少,只有0.4%,主要集中在东湖周边。武汉市中心城区总体绿视率基尼系数为0.49,绿视率分配差异较大,比较不公平。其中,洪山区基尼系数最大,为0.64,绿视率资源分配差距悬殊,江汉区基尼系数最小,为0.47,分配差距较大。武汉市中心城区低熵值区域最多,达29.7%,高熵值区域最少,达15.4%;洪山区、青山区、武昌区内部熵值分配高、低两极明显。用地性质和线性绿化作用是影响研究区绿地公平性的主要因素。研究结果可为优化城市绿地布局提供一定的理论基础和规划参考。

Green space is a kind of resource welfare.The evaluation of green space equity based on green view index(GVI)is important to ensure the equitable distribution of green resources.Taking the central urban area of Wuhan as the research object,based on multi-source data such as Baidu Street View Map,Baidu Thermal Map,and satellite remote sensing images,we evaluated the equity of spatial distribution of GVI in Wuhan by using the locational entropy,Gini coefficient and Lorenz curve.The results showed that 87.6%of the points in the central urban area of Wuhan were below the level of poor green vision,which mainly concentrated in Wuhan Iron and Steel Industrial Base of Qingshan District and south of Yandong Lake.The number of points reaching an excellent level was the least(0.4%),mainly concentrated around the East Lake.The overall Gini coefficient of GVI in the central urban area of Wuhan was 0.49,which indicated that the distribution of GVI was heterogeneous.The Gini coefficient of Hongshan District was the largest at 0.64,indicating a huge gap in the distribution of GVI,while the Gini coefficient of Jianghan District was the smallest at 0.47,with a large gap in the distribution.The central urban area of Wuhan had the most low-entropy areas for 29.7%and the least high-entropy areas for 15.4%.There were two-level differences in entropy distribution within Hongshan District,Qingshan District,and Wuchang District.The nature of land use and the role of linear greenery were the main factors affecting the equity of green space in the study area.Our results could provide theoretical basis and planning reference for optimizing urban green space layout.