北京市高速公路周边土地利用变化对景观格局的影响

高速公路的快速发展在推动经济发展的同时,也对区域的生态环境产生重要的影响。在地理信息系统的支持下,本研究以北京市高速公路网10 km缓冲区为研究区域,利用缓冲区分析、空间分析、统计分析等方法探讨了高速公路周边土地利用变化对景观格局的影响规律。结果表明：① 北京市高速公路周边的土地利用类型主要以建设用地、耕地、林地为主,土地利用变化以耕地向建设用地转入最为显著;② 空间变化上,各缓冲区内土地利用变化以林地、耕地、建设用地的相互转移为主,随着与高速公路的距离增大,土地利用类型从以耕地、建设用地为主逐渐转变为以林地、耕地为主;③ 2005-2015年,各类景观的景观指数变化差异明显,其中水域的斑块密度与分离度指数变化幅度最大,耕地的形状指数增加最快,建设用地的分离度指数减少最多,这与相应的土地利用变化密切相关;④ 基于土地利用变化,北京市高速公路网对周边景观格局的影响范围约为6 km,其中林地转入建设用地以及建设用地与耕地的相互转移是引起公路周边景观空间变化差异的主要原因。

Impacts of Land Use Changes on Landscape Patterns Around Expressways in Beijing

The rapid development of the highway has important effects on the regional ecological environment while promoting economic development. With the support of geographic information system (GIS), this study took the 10 km buffer zone around expressways of Beijing as the research area and used buffer zone analysis, spatial analysis, statistical analysis and other methods to explore the influence of the land use changes around expressways on landscape patterns. The results showed that: (1) construction land, cultivated land and forest land were the main land use types around highways in Beijing during the 10 years. The main land use change was that the cultivated land was transferred into the construction land and it accounted for 80% of all imported area. (2) For the spatial changes, the main transferring changes were that forest land, cultivated land and construction land were transferred among each other. With the increase of the distance from expressways, the main land use types changed from the cultivated land and construction land into woodland and farmland. (3) In 2005-2015, the differences of landscape indices changing were obvious in each landscape type. The changes of patch density and splitting index of water were the biggest, the shape index of cultivated land showed the fastest increasing, and the splitting index of construction land reduced a lot, which were closely related to the land use transfer. (4) Based on the land use changes, the affected range of the highway network on landscape pattern was about 6 km in Beijing and it mainly caused the patch density, landscape shape index, diversity index reduced and aggregation index increased. The main reason for differences in the spatial change of the landscape around expressways was the transfers between construction land and cultivated land and the change of forest land into construction land.