Modelling the effect of temperature changes on plant life-form distribution across a treeline ecotone in the tropical Andes

ABSTRACT

Background: Classifying species from the high tropical Andes into plant life forms (PLF) can provide a more functional understanding of tropical treeline dynamics. However, little is known about the potential response of PLFs to climate warming.

Aims: The objective of this work was to evaluate the response of PLFs to environmental conditions above the upper montane forest in the Venezuelan Andes and forecast their potential distribution under warming scenarios using habitat suitability models.

Methods: We classified species into nine PLFs, analysed their current distribution using CCA and non-linear multiple regressions and forecasted their potential distribution under warming scenarios. We used anatomical leaf traits for shrubs and caulescent rosettes to refine their potential responses to climate.

Results: Tree cover sharply decreased with increasing elevation, while shrub and caulescent rosette distribution differed depending on their leaf traits. Projections suggested an upslope shift of all PLFs with warming and an increase in tree cover.

Conclusions: The analysis of the distribution of PLFs, by linking plant adaptive strategies to topography/climate, allowed projecting changes in vegetation physiognomy in response to warming. Projections of a moderate increase in tree cover in the grassland páramo did not indicate the formation of closed forests above the forest line.

KEYWORDS:

• Climate change
• elevation gradient
• habitat suitability models
• grassland páramo
• plant life-forms
• upper montane forest

Acknowledgements

We are indebted to Mérida Cable Car System and Instituto Nacional de Parques (INPARQUES) for allowing the access to sampling sites. Thanks to A. Heredia for his assistance in fieldwork and to the journal editor Laszlo Nagy and two anonymous referees for their comments and suggestions, which significantly improved the manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

This work was supported by the Russian Ministry of Education Post-doctoral Programme of Project ‘5-100’ [Grant № M 2.2.3] and the LEAF research network (CRN II005) financed by the Inter American Institute for Global Change Research (IAI) and coordinated by Dr Guillermo Sarmiento; Inter-American Institute for Global Change Research (IAI) [LEAF CRNII 005 project]; Russian Ministry of Education [PostDoctoral Programme of Project ‘5-100’].

Notes on contributors

Alberto Arzac

Alberto Arzac is a plant ecologist. His research interest focuses on dendroclimatic studies of Eurosiberian species, quantitative wood anatomy and tree growth modelling.

Luis D. Llambí

Luis D. Llambí is a plant ecologist. His research focuses on the analysis of the patterns and processes influencing plant community assembly and dynamics in the high Andes.

Raphael Dulhoste

Raphael Dulhoste is a forestry engineer. His research interests include the characterisation of water and temperature stress in woody species in cloud forest and grasslands.

José M. Olano

José M. Olano is a plant ecologist. His research interests include dendroclimatic studies of Mediterranean species, quantitative wood anatomy and the evaluation of the impacts of climate change on fungi.

Eulogio Chacón-Moreno

Eulogio Chacón-Moreno is a landscape ecologist. His research focuses on mapping and modelling vegetation and species distributions under climate change scenarios.