Tree diversity is changing across tropical Andean and Amazonian forests in response to global change

Fadrique, B. and Costa, F. and Cuesta, F. and Arellano, G. and Cayuela, L. and Baker, T. R. and Draper, F. C. and Esquivel-Muelbert, A. and ter Steege, H. and Bauters, M. and Aguirre-Gutiérrez, J. and Aguirre-Mendoza, Z. and Alexiades, M. N. and Alvarez-Davila, E. and Arets, E. and Ayala, E. and Aymard, C. G. A. and Baccaro, F. and Báez, S. and Baraloto, C. and Barbosa, R. I. and Barbosa Camargo, P. and Barlow, J. and Barni, P. E. and Barroso, J. and Benchimol, M. and Bennett, A. C. and Berenguer, E. and Blanc, L. and Bonal, D. and Bongers, F. and Brienen, R. and Brown, F. and BT Andrade, M. and Burban, B. and Burnham, R. J. and Camargo, J. L. and Carvalho, S. P. C. and Castilho, C. and Chave, J. and Coelho de Souza, F. and Comiskey, J. and da Costa, L. and de Lima, R. B. and de Oliveira, E. A. and de Oliveira, R. L. C. and de Oliveira Perdiz, R. and De Rutte, J. and del Aguila-Pasquel, J. and Derroire, G. and Di Fiore, A. and Disney, M. and Duque, A. and Emilio, T. and Farfan-Rios, W. and Fauset, S. and Fearnside, P. M. and Feeley, K. J. and Feldpausch, T. R. and Ferreira, J. and Ferreira, L. and Flores Llampazo, G. R. and Galbraith, D. and García-Cabrera, K. and García Criado, M. and Gloor, E. and Grandez-Rios, J. M. and Hérault, B. and Homeier, J. and Honorio Coronado, E. N. and Huamantupa-Chuquimaco, I. and Huaraca Huasco, W. and Huillca-Aedo, Y. T. and Idárraga, Á. and Jadán-Maza, O. and Kalamandeen, M. and Killeen, T. J. and Laurance, S. G. W. and Laurance, W. F. and Levesley, A. and Lopez, W. and Macía, M. J. and Magnusson, W. E. and Malhi, Y. and Manzatto, A. G. and Marimon, B. S. and Marimon Junior, B. H. and Martínez-Villa, J. A. and Medeiros, M. B. and Melgaço, K. and Melo, L. and Metzker, T. and Monteagudo, A. and Morandi, P. S. and Myers, J. A. and Nascimento, H. M. and Nascimento, R. and Neill, D. and Nieto-Ariza, B. and Palacios, W. A. and Palacios-Ramos, S. and Pallqui-Camacho, N. C. and Pardo Molina, G. and Peacock, J. and Peña, M. A. and Pennington, R. T. and Peñuela, M. C. and Peres, C. A. and Pérez, Á. J. and Pickavance, G. C. and Pinto, E. and Pipoly, J. and Pitman, N. and Prieto, A. and Ramírez-Angulo, H. and Reis, S. M. and Restrepo, Z. and Reynel, C. and Ribeiro, S. and Rivas-Torres, G. and Rojas, R. and Rudas, A. and Salinas, N. and Salomão, R. P. and Santana, F. and Schietti, J. and Schwartz, G. and Serrano, J. and Silman, M. and Silva, C. A. and Silva, C. A. and Silva, R. C. and Silva, R. S. A. and Silva-Espejo, J. and Silveira, M. and Simon, M. F. and Soto-Shareva, Y. C. and Souza, P. F. and Storck-Tonon, D. and Stropp, J. and Swamy, V. and Tello, J. S. and Terborgh, J. and Thomas, R. and Torres-Lezama, A. and Vale, J. D. and Valenzuela Gamarra, L. and van der Heijden, G. and van der Hout, P. and van der Meer, P. J. and Vasquez Martinez, R. and Vedovato, L. and Verbeeck, H. and Vieira, I. and Vieira, S. A. and Vilanova, E. and Vinceti, B. and Vos, V. A. and Zagt, R. and Zuidema, P. A. and Phillips, O. L. (2026) Tree diversity is changing across tropical Andean and Amazonian forests in response to global change. Nature Ecology and Evolution. ISSN 2397-334X

Abstract

Climate and atmospheric changes are impacting forest function and structure worldwide, but their effects on tropical forest diversity are unclear. Nowhere is the scientific challenge greater than in the Andes and the Amazon, which together include the world’s most diverse forests. Here, using 406 permanent plots spanning four decades of intact lowland and montane forest dynamics, we test for long-term change in species richness and assess the influence of climate and other variables. We show that, at a continental scale, species richness appears stable, but this masks substantial regional variation. Species richness increased in Northern Andean and Western Amazon plots, yet declined in the Central Andes, Guyana Shield and Central-Eastern Amazon. Overall, warmer, drier and more seasonal forests lost species, while those at higher elevations, in less fragmented areas and with faster rates of tree turnover experienced increases. Region-specific drivers, particularly precipitation seasonality and demographic factors, modulated these trends. The results highlight the diverse ways in which Amazon–Andes forests are changing and underscore the critical need to preserve large-scale ecosystem integrity to maintain local tree diversity. By doing so, Northern Andean forests in particular could serve as an important refuge for species increasingly displaced by climate change.