西南山区地形因子对农村零散居民点分布的影响

为探究西南山地地形因子对农村零散居民点分布的影响,以巫溪县(中山区域)和酉阳县(中低山区域)的农村零散居民点分布为研究对象,结合GIS软件和随机森林模型,探讨了不同地形因子下农村零散居民点的分布特征以及高程、坡度、坡向、地形粗糙度、平面曲率、剖面曲率、地形特征指数、地形部位指数等8个地形因子对农村零散居民点分布影响的重要程度。结果表明:山地农村零散居民点多分布于海拔600~1 200 m的缓地与斜坡以及位于半阳坡与阳坡、中坡位、地形特征指数小于-0.010、平面曲率和剖面曲率接近于0的区域,说明山地区域农村零散居民点多分布于垂直方向上的中高地形位、水平方向上以低变化率地形位为主的区域;影响中低山地农村零散居民点分布的主要地形因子为地形粗糙度、平面曲率和坡度;其中,影响中山区域的农村零散居民点分布的最重要的地形因子是地形粗糙度,而中低山区域则是平面曲率。

The Influence of Terrain Factors on the Distribution of Rural Scattered Settlements in the Mountainous Areas of Southwest China

To understand the influence of terrain factors on the distribution of the rural scattered settlements in mountainous region, a study in two typical counties located in middle altitude and middle to low altitude regions in Southwest China was conducted. Eight terrain factors, such as elevation, slope, aspect, terrain ruggedness index, plan curve, profcurve, terrain characterization index, and terrain position index were extracted by GIS software. The Random Forest model was employed to investigate the relationships between terrain factors and the distribution of the rural scattered settlements. The results showed that the rural scattered settlements were mostly located in areas with elevation of 600-1200 m, gentle slope and slope, half-sunny slope and sunny slope, middle terrain position, terrain characterization index<-0.01, plan curve and profcurve close to zero. This indicated that the rural scattered settlements in mountainous region were mostly built on medium and higher terrain in the vertical direction and relatively flat position in the horizontal direction. The results of random forest model suggested that terrain ruggedness index, plan curve and slope were the most important terrain factors affecting the distribution of the rural scattered settlements in the mountainous areas. Among them, terrain ruggedness index and plan curve played the critical role in middle altitude region and low altitude region, respectively.