城镇化过程中福建省山区县农村聚落景观格局变化特征

农村聚落是农村居民与其周围环境相互作用的现象与过程,是城乡二元关系发展的重要一环,科学评估山地型农村聚落景观时空变化及影响因素对山地城镇化发展具有重要意义。选取了城镇化迅速发展的福建省上杭县作为案例,使用2004年与2014年高分辨率遥感影像、DEM等数据,运用RS、GIS及Fragstats技术,定量分析了上杭县农村聚落景观变化过程、格局趋势。研究表明:(1)2004—2014年上杭县农村聚落数量出现大幅下降,空间分布态势并没有发生太大变化,主要集中在西部汀江水系与东北部,并有进一步加强的趋势,Voronoi模型Cv值结果表现出这一趋势,但最近邻分析结果却显示出2014年相对2004年略微分散。(2)Ripley's K函数显示山地型农村聚落集聚与分散存在尺度效应,65km以内都表现出集聚趋势,2004年在35km处出现最高集聚状态,2014年则在15km集聚达到最高之后出现缓慢下降,并且在30km尺度范围内集聚程度大于2004年。(3)坡度、水系与道路对山地型农村聚落有显著影响,坡度5°是最为关键的因素,10°是一个阈值,80%的农村聚落都分布在10°以内;67%以上的农村聚落分布在距河流湖泊2km范围内;交通对农村聚落影响愈发显著,98.28%聚落分布在交通道路500m范围,未来推进山地城镇化应更加重视交通的作用。(4)乡镇政府所在地中心村镇面积扩大了4.59倍,远高于一般聚落,是山地城镇化过程中景观变化最剧烈的地区,也是为来应重点发展的地区。研究可为山地型农村聚落建设、山地型城镇化村镇规划理论与决策提供一定借鉴。

Mountain county rural settlement landscape pattern change and spatial characteristics in rapid mountain urbanization process in Fujian province

Rural settlements form an important aspect of the urban-rural relationships because of the interactions between rural dwellers and surrounding environment. The activities in the mountainous rural settlements are restricted by a variety of natural and social factors, therefore, a scientific assessment of the spatial and temporal processes is urgent for the urbanization of these regions. For this reason, we selected Shanghang county, which is experiencing rapid urbanization, as a case study for our work. We used high-resolution remote sensing images and DEM data form the years 2004 and 2014, and extracted data on rural settlements, rivers, roads, and slope information, among others. RS, GIS, and Fragstats techniques were used to quantify the spatio-temporal variability in rural settlements. The findings of our study are as follows: (1) spatial pattern of rural settlements did not show a significant change, and these settlements were found to be mainly concentrated in the west and northeast of the Tingjiang River watershed; this was confirmed by the Voronoi model. However, nearest neighbor analysis showed different results, which is more concentrate in 2004 than 2014. (2) Ripley''s K function revealed existence of scale effect in the rural settlement pattern: settlements at a height of less than 65 km showed gathering trends; highest concentrations were found to be at heights of 35 km and 15 km in 2004 and 2014 respectively, and spatial scaling within 30km is more concentrate in 2014. (3) The slopes, river systems, and roads can significantly affect the distribution of the rural settlements. Slope of 10° is the threshold and 80% of rural settlements are spread within 10°, slope of 5° is the most important factor within 10°; more than 67% of the rural settlements are distributed within the 2km buffer zone from the river system; more than 98.28% of the settlements are distributed within the 500m buffer zone of the roads, which implies that greater attention should be paid to the role of roads in the urbanization of mountainous regions in future. (4) The rural settlements located in the government township were found to have expanded 4.59 times than in the past, which is the most dramatic change area of town-village landscape in mountainous urbanization. Besides, we proposed that center town-village settlement is the most critical area, and also key development region. We expect our research to provide a methodological reference for the management and evaluation of rural settlements, and theoretical planning, and decision-making for mountainous urbanization in the future.