Aníbal Pauchard1,2, Alejandra Jiménez1,2, Eduardo Fuentes-Lillo1,2, Rafael García1,2, Lohengrin Cavieres3,2 and Ramiro Bustamante4,2
1Facultad de Ciencias Forestales, Universidad de Concepción, Casilla 160-C, Concepción, Chile
2Institute of Ecology and Biodiversity (IEB), Universidad de Chile, Chile
3Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Chile
4Departamento de Ecología. Facultad de Ciencias, Universidad de Chile, Chile
Homogenization of the world biota is occurring at an unprecedented rate with uncertain consequences for biodiversity at broad intercontinental scales, but also at local or regional scales. Mountains are of great significance for people and biodiversity but are becoming highly degraded and homogenized because of human activities and the introduction of non-native species. Homogenization not only encompasses a change in species composition, but species additions and extinctions can modify the phylogenetic structure of the community. More importantly, in terms of conservation, homogenization can modify the overall ecosystem function by changing the dominant species functional traits. This project aims to understand the current impacts on the biodiversity of mountain ecosystems, specifically in the taxonomic, functional and phylogenetic homogenization of the plant communities and how those processes are driven by climate, disturbance and the local non-native species pool. We are taking advantage of a long latitudinal gradient in the Mediterranean, temperate and subantarctic ecoregions of the Chilean Andes mountains from 32 to 53 degrees latitude south, ranging from almost sea level to 3,500 m.a.s.l. We use a standardized-systematic method of field data collection across two environmental gradients (elevation and latitude) to better understand how biological invasions are causing plant community taxonomic, phylogenetic and functional homogenization. We base our approach in the Mountain Invasion Research Network (MIREN) T-survey protocol and build a comprehensive dataset of environmental, plant community and life-history trait variables to address these questions, which will be complemented by a large scale seed-addition field-experiment in all sites. We hypothesize that across elevational and latitudinal gradients in mountain ecosystems, non-native species homogenize plant communities in their taxonomic, phylogenetic and functional dimensions, and that this process is driven by microclimates, disturbance and the lowland non-native species pools. We also expect that future scenarios associated with climatic warming, higher disturbance in the landscape and larger non-native species pools should increase taxonomic, functional and phylogenetic homogenization of plant communities. Here, we show preliminary results of our first year of this ongoing project and how we have adapted methodological approaches to study biotic homogenizations.