Population dynamics and orientation of the central Andean cushion Azorella compacta

Catherine Kleier; Tim Trenary; Eric A Graham; Philip W Rundel

doi:10.7287/peerj.preprints.607v1

Population dynamics and orientation of the central Andean cushion Azorella compacta

Catherine Kleier ¹, Tim Trenary², Eric A Graham³, Philip W Rundel⁴

1 Department of Biology, Regis University, Denver, CO, USA

2 Department of Mathematics, Regis University, Denver, CO, USA

3 Nexleaf Analytics, Los Angeles, CA, USA

4 Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA, USA

DOI: 10.7287/peerj.preprints.607v1

Published: 2014-11-12
Accepted: 2014-11-12

Subject Areas: Ecology
Keywords: Andes, Parque Nacional Lauca, growth rate, cushion plant, puna

Licence: This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ PrePrints) and either DOI or URL of the article must be cited.

Cite this article: Kleier C, Trenary T, Graham EA, Rundel PW. 2014. Population dynamics and orientation of the central Andean cushion Azorella compacta. PeerJ PrePrints 2:e607v1 https://doi.org/10.7287/peerj.preprints.607v1

Abstract

Azorella compacta (llareta; Apiaceae), a large woody cushion plant, is a remarkable species forming dense cushions and characterizing the high elevation rocky slopes of the central Andean Altiplano. Field studies of an elevational gradient of A. compacta within Lauca National Park in northern Chile found a reverse J-shape distribution of size classes of individuals with abundant small plants at all elevations. A new elevational limit for A. compacta was found at 5250 m. A series of cushions marked 14 years earlier showed either slight shrinkage or small degrees of growth up to 2.2 cm yr^-1. Despite their irregularity in growth, cushions of A. compacta show a strong orientation, centered on a north-facing aspect and angle of about 20^o from horizontal. This exposure to maximize solar irradiance closely matches previous observations of a population favoring north-facing slopes at a similar angle. Populations of A. compacta appear to be stable, or even expanding, with young plants abundant and recolonization of disturbed habitats.

Author Comment

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