黄土丘陵区乡村聚落时空演变特征及格局优化——以七里河区为例

Spatial-Temporal Evolution Characteristic and Pattern Optimization of Rural Settlement in the Loess Hilly Region—Take Qilihe District for Example

乡村聚落是农户的居住场所,对其空间格局进行研究,对实现城乡一体化发展和推进新农村建设具有实践意义。基于2002年的Landsat 7 ETM和2012年的SPOT 5遥感影像,采用实地访谈法,景观格局分析和GIS空间分析相结合的方法,对七里河区乡村聚落的时空演变特征、过程、机理及空间格局优化四个方面进行深入探讨。结果表明:110年来,全区乡村聚落发展较快,斑块数目增多,平均斑块面积减小,但不同地域发展程度存在明显差异,集镇中心及三条沟谷地带分布逐渐密集,空间上总体呈现"融合—迁移"之演变趋势。2乡村聚落向地形平坦、交通和水系沿线布局的趋向明显,地形梯度在3级以下,距离道路和河流1 000m是乡村聚落发展的主要集聚区,同时乡村聚落的演变受农户耕作半径、中心城市的发展影响较大。3城镇化与工业化、农业产业化、土地经营方式的转变、农户生计的改变、政策制度的实施等因素是全区乡村聚落空间演变的主要驱动力。4结合全区社会经济、人口、自然环境、聚落布局等情况,提出城镇化整理型、集聚发展型和迁移型三种优化空间格局模式。

Rural settlement is the living place of peasant household. Research on spatial pattern of rural settlement can provide practical significance for the achievement of urban and rural integration development and the promotion of new countryside construction. Based on Landsat7 ETM in 2002 and remote sensing image SPOT5 in 2012, this paper conducts in- depth discussions on rural settlement of Qilihe District from the four aspects of spatial- temporal evolution characteristic, process, mechanism and spatial pattern optimization of rural settlement through field interview and combining landscape patter analysis and GIS spatial analysis. The results indicate that： firstly, in the recent decade, rural settlement of the region has witnessed rapid development with increasing patch numbers and decreasing mean patch area.However, degree of development varies markedly in different regions. Settlement layout becomes increasingly intensive in the town center and the three valleys, and the general evolution trend shows＂fusion- migration＂in space. Secondly,layout trend of rural settlement is obvious in flat topographyand, and along traffic and rivers. Terrain gradient is below3 rd class. The main gathering area of rural settlement is 1000 m distant from road or river. Meanwhile, cultivating radius of farmers and the development of central city have a significant impact on the evolution of rural settlement. Thirdly,there are many driving mechanism factors for spatial- temporal evolution of rural settlement of the region, such as urbanization, industrialization, agricultural industrialization, transformation of land management, change of farmer＇s livelihoods, implementation of policies and systems, etc. Lastly, combining the conditions of social economy, Population,natural environment and settlement layout, this paper put forwards three measures to regulate the optimization space pattern-the rationality of urbanization, cluster development and cluster migration.