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Unsupervised mapping of urban tree diversity using spatially-aware visual clustering


Abstract

Urban tree biodiversity is critical for climate resilience, ecological stability, and livability in cities, yet most municipalities lack detailed knowledge of their canopies. Field-based inventories provide reliable estimates of Shannon and Simpson diversity but are costly and time-consuming, while supervised AI methods require labeled data that often fail to generalize across regions. We introduce an unsupervised clustering framework that integrates visual embeddings from street-level imagery with spatial planting patterns to estimate biodiversity without labels. Applied to eight North American cities, the method recovers genus-level diversity patterns with high fidelity, achieving low Wasserstein distances to ground truth for Shannon and Simpson indices and preserving spatial autocorrelation. This scalable, fine-grained approach enables biodiversity mapping in cities lacking detailed inventories and offers a pathway for continuous, low-cost monitoring to support equitable access to greenery and adaptive management of urban ecosystems.

Data availability

All data supporting the findings of this study are available within the paper and its supplementary information. The code used for analysis is available at https://github.com/Diaa340/Releaf/.

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Acknowledgements

The authors thank Dubai Future Foundation, UnipolTech, Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, Volkswagen Group America, FAE Technology, Samoo Architects & Engineers, Shell, GoAigua, ENEL Foundation, Kyoto University, Weizmann Institute of Science, Universidad Autónoma de Occidente, Instituto Politecnico Nacional, Imperial College London, Universitá di Pisa, KTH Royal Institute of Technology, AMS Institute and all the members of the MIT Senseable City Lab Consortium for supporting this research. This work was supported by the Open Access Program from the American University of Sharjah, UAE.

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This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

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M.M., F.D., I.Z., M.S., and D.A.A. conceptualized the study. D.A.A. and M.S. performed the methodology development and data curation, conducted the formal analysis, and wrote the original draft. M.M., F.D., and I.Z. supervised the research, C.R. provided resources, and handled funding acquisition. All authors reviewed and edited the manuscript. This paper represents the opinions of the author(s) and does not mean to represent the position or opinions of the American University of Sharjah.

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Diaa Addeen Abuhani or Martina Mazzarello.

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Abuhani, D.A., Seccaroni, M., Mazzarello, M. et al. Unsupervised mapping of urban tree diversity using spatially-aware visual clustering.
Sci Rep (2026). https://doi.org/10.1038/s41598-026-37043-7

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  • DOI: https://doi.org/10.1038/s41598-026-37043-7

Keywords

  • Biodiversity
  • Unsupervised Learning
  • Clustering
  • Streetviews


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