豫东平原聚落景观格局变化

中国的快速城镇化必然导致聚落景观格局的变化,但目前相关研究对平原地区关注相对较少。文中选取豫东平原地区的开封、商丘、周口市,运用GIS空间分析方法和ENVI遥感影像处理技术,对该地区1972、2015年市域中观尺度上的聚落规模、聚落景观空间变化特征进行分析。结果显示:(1)在聚落发展过程中,1972—2015年聚落斑块数量有所减少,聚落规模逐渐扩张,市域内最大聚落斑块扩张相对更为明显;对聚落斑块扩张强度的分析发现,城市市辖区及周边乡镇聚落扩张强度相对较高。(2)地区内聚落斑块空间分布表现出聚集分布特征,但该时期聚集程度有所减弱;两个年份聚落核密度分布格局大致相似,局部地区存在多核扩散现象,市域尺度上的核密度分布存在地区差异。(3)对斑块形状指数的分析发现,研究区狭长或曲折聚落斑块在空间上分散布局,整体上区域内聚落形状趋于规则。(4)随着距河流、道路距离的增加,聚落斑块总面积和数量有所减少,且道路对聚落分布仅在一定范围内存在较大影响,距中心城市0—6km范围内聚落受中心城区发展辐射影响较大。本文的分析可为平原地区聚落景观的优化布局和聚落用地的集约化发展提供一定的参考。

Changing patterns of settlement landscape in the Eastern Plain of Henan Province

Rapid urbanization in China has elicited a change in the pattern of settlement landscape, particularly for the plain area with its long history of human settlement. However, relevant research is lacking. By employing the spatial analysis method of GIS and remote sensing image processing technology of ENVI, we analyzed the characteristics of changes of Kaifeng, Shangqiu, and Zhoukou in the Eastern Plain of Henan Province with respect to settlement size and spatial distribution on a meso-scale from 1972 to 2015. The results indicated that, first, the number of settlement patches decreased, whereas their sizes gradually expanded, and the built-up areas of the respective cities expanded noticeably. Furthermore, the village patches surrounding the urban areas experienced a greater expansion than other village patches. Second, the spatial distribution of settlement patches in the study area exhibited a clustered distribution; however, the degree of agglomeration declined in 2015. The kernel density distribution of settlement patches was stable, although multi-core diffusion existed in some regions, and the density distribution was different among cities. Third, the patch shape index (PSI) revealed that the narrow or tortuous patches were spatially scattered, and the shape of settlements was relatively regular in 2015. Finally, as distance from rivers and roads increased, the total size and number of settlement patches decreased; however, the effect of roads on settlement distribution was only detected in certain regions. The settlement patches located within the 6 km buffer zone of the respective central cities were affected by development of the urban areas. The results presented here could assist in the optimal layout of settlement landscape and the intensive development of settlement land-use in the Eastern Plain of Henan Province.