【摘要】 植被覆盖与地形、气候等自然因子密切相关，但短期内则更受人类活动的影响。为分析北京中心城区植被覆盖时空变化及其地形分异规律以及土地利用转变对于植被覆盖度变化的影响，本研究借助遥感技术，通过改进后的像元二分模型获取北京市中心城区不同时间段植被覆盖以及通过监督分类获取对应的土地利用类型，并结合数字高程模型(DEM)数据，通过地理信息系统(GIS)对所得数据综合分析。结果表明：研究区1992-2020年植被覆盖度总体上呈现出由早年的退化为主到近些年来的改善为主，1992-2011年低植被覆盖度不断增加，而2011-2020年则是高植被覆盖不断增加；植被覆盖度受到地形影响显著(P <0.01)。总体上，植被覆盖度与海拔和坡度呈正相关关系；坡向上除平地外，其余坡向植被覆盖度差距不大，阴坡较高，阳坡较低；研究区城市扩张不断占用林地、草地和耕地，是植被覆盖退化的主导因素，而未利用地开发、城市郊野公园建设、退耕还林还草为植被覆盖增加的主导因素。研究可为快速城镇化地区的土地利用与生态环境协调提供有力的科学支撑。更多还原

【Abstract】 Vegetation coverage is closely related to natural factors such as topography and climate, but it is more affected by human factors in the short term. This study aimed to analyze the temporal and spatial variation of vegetation coverage in the central urban area of Beijing and its topographical differentiation, as well as the impact of land use transition on changes in vegetation coverage. We used remote sensing technology to obtain the data of different periods of vegetation coverage in the central urban area of Beijing through the improved pixed dichotomous model and its land-use type supervised classification method. These data, combined with digital earth model data, were comprehensively analyzed by geographic information system. The results showed that, during 1992-2020, the vegetation coverage of the study area generally showed a trend of degradation increase from 1992 to 2011, while the high vegetation coverage increased from 2011 to 2020. Vegetation coverage is significantly affected by topography and is positively correlated with elevation and slope. There is no significant difference in vegetation coverage on the slopes; vegetation coverage is higher on shady slopes and lower on sunny slopes.The urban expansion of the study area continues to occupy forestland, grassland, and cultivated land and is the leading factor of vegetation degradation. However, the development of unused land, urban suburban park construction, and reconversion of farmland to forestland or grassland are the leading factors of the increase in vegetation coverage. This study can provide strong scientific support for the coordination of land use and ecological environment in rapid urbanization areas.更多还原