Biodiversity and structural analysis of forests at the altitudinal boundary between dry and montane forests: response of tree diversity to altitudinal variation in the northeastern Peruvian Andes

Coronel-Castro E.; Pariente-Mondragón E.; Rivera R.Y.; Chacón J.; Delgado A.; Oliva-Cruz M.; Huamán-Pilco A.F. · Frontiers in Forests and Global Change (2026) · DOI: 10.3389/ffgc.2026.1765957

Resumen

Forests at the altitudinal limits between seasonally dry tropical forests (SDTF) and montane forests in northeastern Peru are key for biodiversity and ecological connectivity. Sixteen 0.1-ha plots were surveyed along a 1900–2700 m a.s.l. gradient, recording 133 species, 76 genera, and 47 families, reflecting high floristic heterogeneity. Diversity indices showed a unimodal pattern, peaking in the transition zone between 2300 and 2500 m (Hill_q1 = 22.36; Hill_q2 = 15.92; estimated richness = 49 species). Diversity decreased at lower SDTF elevations (1900–2100 m) and higher montane sites (>2500 m), likely due to thermal and water limitations. Species dominance shifted along the gradient: Vachellia aroma and Inga adenophylla dominated SDTF, whereas Aiouea montana, Clethra revoluta, and Ilex scopulorum characterized montane forests. Beta diversity revealed pronounced species replacement and highlighted plot S08 as an ecotone with species from both ecosystems. Diameter-class distributions followed an inverted “J” pattern, indicating active regeneration in both ecosystems, with higher recruitment in SDTF. Altitude drives species replacement and shapes a unimodal diversity pattern. We recommend restoring dominant SDTF species, such as Vachellia aroma and Inga adenophylla, in degraded lower-elevation areas, and conserving ecotonal belts as altitudinal corridors to enhance biodiversity and climate resilience areas, and conserving ecotonal belts as 32 altitudinal corridors to enhance biodiversity and climate resilience. Copyright

Instituciones: Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas