This model of tree species richness demonstrates the diversity of LA’s urban forest. Each pixel in the map represents the average number of tree species found at that location.
Scientists often use the normalized vegetation difference index (NDVI) to measure the greenness of vegetation. Information for the index is collected via satellites. Studies have shown that NDVI has a significant positive relationship with species richness. The estimates in this model are the results of a study that compared NDVI with field observations of tree species richness in plots across LA.
While these model results are for 2011, the formula could be updated with NDVI and field observations from any given year. Additional data observations help to build more robust, accurate results.
Data layer derived from: Gillespie, T. W., de Goede, J., Aguilar, L., Jenerette, G. D., Fricker, G. A., Avolio, M. L., … & Pataki, D. E. (2017). Predicting tree species richness in urban forests. Urban Ecosystems, 20, 839-849. doi.org/10.1007/s11252-016-0633-2