巫山县乡村地区公路网通达性空间格局研究

以巫山县为研究区域，运用GIS技术，以乡镇和行政村为节点单元，采用公路网密度、乡镇间直达性指数、乡镇内直达性指数、居民点道路临近性、乡镇间节点可达性指数、乡镇内节点可达性指数、干线衔接距离、地形位指数8项指标，引入熵权-TOPSIS模型，综合分析和评价巫山县乡村地区公路网通达性及其空间分布格局。研究表明，各项指标对巫山县乡村公路网的影响程度由高到低为：公路网密度＞地形位指数＞干线衔接距离＞居民点临近性＞乡镇内直达性指数＞乡镇间节点可达性指数＞乡镇内节点可达性指数＞乡镇间直达性指数；除中心城区外，各乡镇贴近度为0.170 0＞0.831 9，区域差异明显，其中铜鼓最高，当阳最低；整体上，巫山县乡村公路通达性以中等、较好等级为主，通达性空间格局总体以铜鼓、建平、三溪为核往外围扩散，与交通干线骨架吻合度较高，呈现“三核、一环、一域”的空间格局。研究成果对巫山县山区乡村公路网建设和优化有一定的指导作用，在一定程度上完善了乡村地区公路网通达性分析和评价方法。

Research on the spatial structure of rural highway accessibility in Wushan county

Based on the GIS technology, this study comprehensively analyzes the accessibility and spatial distribution structure of rural highway in Wushan county by using entropy-weight TOPSIS method with 8 research indicators, taking towns and villages as the nodes. The results show that the influence of the indexes ranks as follows: highway network density > topographic location > trunk link distance > residential area proximity > direct arrival for nodes within the same towns > accessibility between different towns > accessibility for nodes within the same town > direct arrival between different towns. Beside the central urban area, the closeness of all towns ranges from 0.170 0 to 0.8319, with obvious regional variation, in which Tonggu ranks the highest while Dangyang ranks the lowest. In general, accessibility of rural roads in Wushan county is estimated as mainly medium and good levels. It also takes a good consistency with the backbone of the traffic trunk line, presenting a spatial structure of “three cores, one ring and one domain”, which declines outside the three core areas in Tonggu, Jianping and Sanxi. Our study contributes to the construction and optimization of rural highway network in Wushan mountainous area, improving the analysis and evaluation method of highway network accessibility in rural areas to some extent.