Presentation

Trees provide essential ecosystem services, such as carbon storage or local temperature regulation, and play an important role in climate change resilience, particularly in urban areas. Quantifying these services in cities is difficult because there is little information about individual trees and no allometric model currently exists for urban trees.
UrTrees calls on citizens to help collect measurements and increase our knowledge of the key features of urban trees. With the UrTrees mobile application, only a short video around the tree is needed to measure three essential features: tree height, trunk diameter at breast height (1m30 above ground) and crown volume. No special expertise on trees is required to use UrTrees!
Technically, a three-dimensional point cloud of the digitized tree is first derived from the video. Geometric models of the trunk and crown are then fitted to the point cloud to estimate key measurements (see video). All measurements are stored in a database providing data for urban tree studies (see contributions). To improve the user experience, a scoring system, daily quests, and an interactive visualization of the point cloud are included in the app.