Article asserts that urban tree canopies are a significant sink for atmospheric elemental carbon (EC)--and air pollutant that is a powerful climate-forcing agent and threat to human health. The authors' findings indicate that complex configurations of roads, buildings, and vegetation produce “urban edge trees” that contribute to heterogeneous EC deposition patterns across urban systems, with implications for greenspace planning.

Article describes the efficient and accurate identification of canopy gaps is the basis of forest ecosystem research, which is of great significance to further forest monitoring and management. One major limitation of the traditional methods of remote sensing to map canopy gaps is that they cannot finely extract the complex edges of canopy gaps in mountainous areas. The authors proposed an object-oriented classification method that integrates multi-source information.