摘要
城市不透水面既是常用的城市化程度指标,也是衡量环境质量的重要指标。采用遥感技术准确提取城市不透水面并分析其空间扩张过程,对生态城市建设具有重要意义。基于Landsat 5 TM影像,采用NDVI二元法和线性光谱分解法,分别提取北京、天津和唐山3个城市不透水面信息,并将不透水面估算结果与近同期的ALOS影像提取结果对比验证。结果表明,线性光谱分解法获取的不透水面结果较好,RMSE为20.6%,能有效提取大范围的不透水面信息。
Impervious surfaces are mainly anthropogenic features such as paved roads, rooftops, driveways, sidewalks, and parking lots that are covered by impenetrable materials. With the urban expansion, vegetation and soils are replaced by impervious surfaces, which become a major ecological and environmental concern. This is because the increase of impervious surfaces generally leads to the decrease in vegetation, wetlands and agricultural lands, and consequently, to a series of environmental problems, such as the decease of groundwater recharge, the increase of surface runoffs and flood frequency and urban heat islands. The percent cover of impervious surfaces, as well as its spatial pattern, has been widely used as an indicator to quantify the urbanization level and urban environmental quality, and is essential to understand the interactions between human and the environment. Therefore, accurate mapping and estimating impervious surfaces is crucial for environmental and resources management. In this study, we compared and evaluated two methods： the Normalized Difference Vegetation Index （NDVI） based binary approach and the Linear Spectral Unmixing （LSU） method. These two approaches have been frequently used in mapping impervious surfaces. With the NDVI based binary approach, impervious surfaces are extracted based on information on vegetation distribution that can be well represented by NDVI,. Then vegetation fractional coverage was first estimated from a scaled NDVI, and then impervious surfaces were estimated as by subtracting the vegetation fraction from 1. This approach had the merit of simplicity. However, large errors may occur in impervious surface estimation. The LSU approach is based on the vegetation-impervious surface-soil （V-I-S） model proposed by Ridd in 1995, a novel conceptual model for remote sensing analysis of urban landscapes. The VIS model indicated that land cover in urban environment is a linear combination of these three components, that is, vegetation, impervious, and soils. The LS
出处
《生态学报》
CAS
CSCD
北大核心
2015年第13期4390-4397,共8页
Acta Ecologica Sinica
基金
国家自然科学基金面上项目(41371197)
省部级项目(STSN-12-01)
