河南省人口分布与乡镇可达性空间耦合特征

人口作为区域发展的内在因素，交通可达性提高将有利于促进人口或劳动力要素的自由流动和优化配置。在考虑土地利用及地形因素的基础上，采用包含乡村道的交通网络数据集，应用改进的成本距离计算方法，分析河南省乡镇可达性及其分布特征；通过乡镇可达性与人口密度的空间叠加，揭示人口分布与可达性的空间耦合特征。结果表明：①各乡镇可达性总体呈现明显的圈层分布，可达性值由内向外逐渐降低；时段越短，内部差异越大，交通指向越明显。②乡镇可达性与人口密度在各时间圈呈现正相关关系，可达性与人口分布集聚产生作用的最大时间距离为1.5h。③人口与交通可达性的空间耦合呈现较明显的半环状分布，社会经济指向性明显。④交通可达性对人口变化的影响具有时间阶段性和区域差异性。

SPATIAL COUPLING FEATURES OF POPULATION AND TOWNSHIP ACCESSIBILITY DISTRIBUTION IN HENAN PROVINCE

Population is the internal factor of regional development. Higher accessibility could improve population mobility and optimize the allocation of labor force elements. The paper aims to uncover the spatial coupling features of township accessibility and population distribution in Henan province. The paper used detailed road network datasets which include express railway, expressway, railway, state highway, provincial highway, county way and rural road to determine the cross cell time(CCT) as the travel cost. In non-road area, the CCT is calculated by walking speed which estimated by topographic and land use factors on the basis of Shuttle Radar Topography Mission(SRTM) data and GlobeLand30 data in 2010. Using improved cost distanced methods by the access points with entry of highway and railway station, the paper calculated 6 time zones accessibility with 0.5-hour time interval for all 2096 towns in Henan province. The number and spatial distribution of 6 time zones accessibility are analyzed by Jenks classification method. Finally, the Pearson correlation coefficient is calculated with all towns accessibility and population density, and the spatial differentiation is analyzed by overlaying the town accessibility and population density.