A Regional Red List of Montane Tree Species of the Tropical Andes: Trees at the top of the world

Andean montane forests are a major global conservation priority owing to their biological richness and high level of species endemism. Botanically the Andes are very rich in species but they remain relatively unstudied. In common with montane forests elsewhere in the world, Andean forests are of great value for the provision of ecosystem services relating to water supply, regulation of regional climate and the capture and storage of carbon. The forests and their component species are however under threat. This report summarises information drawn from a wide variety of sources to provide a regional Red List of trees of Andean tropical montane forests. The species evaluation process has drawn on published national red lists of threatened species, botanical literature, specimen databases, forestry information and expert knowledge. The IUCN Red List Categories and Criteria have been used for the evaluation and a component of Natalia?s PhD study has been to evaluate their use for species with limited and dispersed data. Understanding the geographical distribution of the species is very important in conservation assessment. The maps produced for this study are a valuable starting point for the Red Listing and a baseline for monitoring impacts of climate change. In this assessment 70 species are recorded as globally threatened based on the IUCN Red List of Categories and Criteria out of 127 tree species evaluated. In addition 165 national endemic trees of the region have previously been evaluated as globally threatened based on the same IUCN process. In total therefore 235 tree species are currently considered to be threatened with extinction within the Andean montane forests.Fil: Tejedor Garavito , Natalia. Bournemouth University; Reino UnidoFil: Álvarez Dávila, Esteban. Jardín Botánico de Medellín; ColombiaFil: Caro, Sandra Arango. Missouri Botanical Garden; Estados UnidosFil: Murakami, Alejandro Araujo. Museo de Historia Natural Noel Kempff Mercado; BoliviaFil: Baldeón, Severo. Universidad Nacional Mayor de San Marcos; PerúFil: Beltrán, Hamilton. Universidad Nacional Mayor de San Marcos; PerúFil: Blundo, Cecilia Mabel. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Laboratorio de Investigaciones Ecológicas de las Yungas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Boza Espinoza, Tatiana Erika. Missouri Botanical Garden; Estados UnidosFil: Fuentes Claros, Alfredo. Herbario Nacional de Bolivia; BoliviaFil: Gaviria, Juan. Universidad de Los Andes; VenezuelaFil: Gutiérrez, Néstor. Universidad de Los Andes; VenezuelaFil: Khela, Sonia. Botanic Gardens Conservation International; Reino UnidoFil: León, Blanca. University of Texas at Austin; Estados UnidosFil: la Torre Cuadros, Maria De Los Angeles. Universidad Nacional Agraria; PerúFil: López Camacho, René. Universidad Distrital; ColombiaFil: Malizia, Lucio Ricardo. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias. Centro de Estudios Ambientales Territoriales y Sociales; ArgentinaFil: Millán, Betty. Universidad Nacional Mayor de San Marcos; PerúFil: Moraes R., Mónica. Herbario Nacional de Bolivia; BoliviaFil: Newton, Adrian C.. Bournemouth University; Reino UnidoFil: Pacheco, Silvia. Fundación Proyungas; ArgentinaFil: Reynel, Carlos. Universidad Nacional Agraria; PerúFil: Ulloa Ulloa, Carmen. Missouri Botanical Garden; Estados UnidosFil: Vacas Cruz,Omar. Pontificia Universidad Católica del Ecuador; Ecuado

Spatial patterns of above-ground structure, biomass and composition in a network of six Andean elevation transects

Background: The Amazon to Andes transition zone provides large expanses of relatively pristine forest wilderness across environmental gradients. Such elevational gradients are an excellent natural laboratory for establishing long-term interactions between forest ecosystems and environmental parameters, which is valuable for understanding ecosystem responses to environmental change. Aims: This study presents data on elevational trends of forest structure (biomass, basal area, height, stem density), species richness, and composition from six elevational transects in the Andes. Methods: We analysed the spatial patterns of forest structure, above-ground biomass and composition from 76 permanent plots, ranging from lowland Amazonian rain forest to high-elevation cloud forests in Ecuador, Peru, and Bolivia. Results: Forest above-ground woody biomass stocks ranged from 247 Mg ha −1 (Peru, 210 m) to 86 Mg ha −1 (Peru, 3450 m), with significantly decreasing trends of tree height and biomass and an increasing trend of stem density with increasing elevation. We observed an increase in forest richness at three taxonomic levels at mid-elevation, followed by a decrease in richness within the cloud immersion zone. Conclusions: The transects show an increase in stem density, a decline in tree height and above-ground coarse wood biomass and a hump-shaped trend in species richness with increasing elevation. These results suggest that environmental change could lead to significant shifts in the properties of these ecosystems over time