基于eCognition影像解译的云南会泽县建成区林木树冠覆盖分析

Analysis of Tree Canopy Cover in Built-up Srea of Huize County, Yunnan Province Based on eCognition Image Interpretation

城市生态建设是解决城市化进程所导致的环境恶化的有效途径,林木树冠覆盖是衡量城市生态的标志性指标,反映森林城市建设的成效,对林木树冠覆盖的分析结果可为我国西南地区中小型城市的森林城市建设提供参考。以会泽县建成区2019年7-8月的0.5m分辨率航空遥感影像为基础,基于ArcGIS10.4平台,利用eCognition 9.0软件解译,结合多尺度分割算法处理,计算分析会泽县建成区林木树冠覆盖率及斑块分布情况。结果表明,会泽县建成区现实林木树冠覆盖面积为275.55hm~2,由城市中心逐渐向四周扩散呈递增趋势,林木树冠覆盖率为17.78%。共5 270个斑块,整体城市林木面积小且数量多,破碎化严重。潜在林木树冠覆盖率为8.98%,共2 067个斑块,能达到的最大林木树冠覆盖率理论值仅为26.76%。新旧居住区斑块分布差异性显著,城市森林的建设对城市生态的提升起到一定积极促进作用。

Urban ecological construction is an effective way to solve the environmental deterioration caused by the urbanization process, forest canopy coverage is a landmark index to measure urban ecology and reflect the effectiveness of forest city construction, the analysis results of forest canopy coverage can provide reference for the forest city construction of small and medium-sized cities in southwest China.Based on the 0.5 m resolution aerial remote sensing images in the built-up area of Huize County from July to August 2019,and the ArcGIS10.4 platform, the canopy coverage and patch distribution of trees in the built-up area of Huize County were calculated and analyzed by using eCognition 9.0 software interpretation and multi-scale segmentation algorithm processing.The results showed that the actual canopy coverage of trees in the built-up area of Huize County was 275.55 hm~2,which gradually spread from the urban center to the surrounding areas, showing an increasing trend, and the canopy coverage rate of trees was 17.78%.There were 5 270 patches in total, and the overall urban forest was small in area but big in number, with serious fragmentation.The potential forest canopy coverage was 8.98%,with a total of 2 067 patches, and the theoretical value of the maximum forest canopy coverage that could be achieved was only 26.76%.The patch distribution of new and old residential areas was significantly different, and the construction of urban forest played a positive role in promoting the improvement of urban ecology.