The city of Zürich maintains a tree database, where all trees planted by the municipal gardeners (Grün Stadt Zürich) are recorded. But cities do not only green because of the work of the municipality: garden and balcony owners also contribute to the greening of the city.
By using LIDAR data, green areas can be analyzed in a more precise and comparable way. Thus, this dataset offers an interesting alternative to measure the greening of municipalities. Carrying out this calculation with LIDAR data is, however, not trivial - especially since the datasets are huge. Finding a methodology that allows for fast and precise analysis of this dataset is therefore very rewarding.
Possible topics for analysis are the extraction of individual trees as points or as tree outlines. Moreover, additional information could be attributed to each extracted tree, such as tree height and crown area. The tree database of the city of Zürich can serve as a validation dataset, as properties like tree position, tree height and tree species are recorded in this dataset.
Both the LIDAR data and the tree data are available as Open Data. The LIDAR data has been obtained in spring 2014. In addition to the X,Y and Z coordinates, other variables such as the pulse return magnitude and the standard set of ASPRS classification are available.