巫山县农村居民点分布与地形因子关系

Distribution of Rural Settlements in Relation to Landform Factors in Wushan County

以重庆市巫山县农村居民点为研究对象,基于分布指数和信息熵,探讨了不同高程、坡度、坡向、地形起伏度、坡度变率和高程变异系数6个地形因子各地形位梯度上农村居民点的分布特征;利用变维分形理论方法定量研究了地形因子对农村居民点分布及其发展的影响。结果表明:各地形条件上研究区农村居民点分布占主导地位的地形位分别为高程250~1 000m,坡度0°~25°,东南、南、西南和西北坡向,地形起伏度0~30m,坡度变率0°~9°,高程变异系数0~0.02;农村居民点的有序度与分布格局体现出高度关联性,在优势地形位上有序度较高;农村居民点与高程、地形起伏度、坡度变率和地形高程变异系数均呈现二阶累积和变维分形分布特征,与坡度、坡向分别呈一阶和三阶累积和分形分布。不同地形因子对研究区农村居民点的影响程度从大到小依次为坡度>高程>坡度变率>地形起伏度>高程变异系数>坡向。

Based on the distribution index and information entropy,we discussed the distribution characteristics of rural residential land of Wushan County on 6 Landform factors on different gradients of elevation,slope,aspect,terrain,slope of slope and variation coefficient in elevation.The influence of landform factors on the distribution and development of rural settlements was quantitatively studied by variable fractal theory.The Results showed that advantageous terrain habitats for rural settlements were characterized by the elevations of 250~1 000 m,slopes with gradients of 0°~25°,aspects of SE,S,SW and NW,terrain undulation of 0~30 m,slopes with change of 0°~9°,variance coefficient in elevation of 0~0.02.The orderly degree and distribution pattern of rural settlements showed a high correlation degree,and the order degree was higher in dominant terrain.The relationship between rural settlements and elevation,terrain undulation,slope change and variance coefficient in elevation fitted the second-order accumulated variable dimension fractal distribution,while the slope and aspect fitted the first-order and third-order,respectively.Thus the influence degree of these landform factors on rural settlements followed the order：slopeelevationslope of slopeterrain undulationvariance coefficient in elevationaspect.