Lichens water regulation dynamics as functional traits could predict future climatic change scenarios in an altitudinal gradient from central argentina

DIAZ DOMINGUEZ, RAÚL; PERALTA, MARIANA; JUAN MANUEL RODRIGUEZ

Simposio; International Association for Lichenology 9th Symposium (IAL 9); 2021

Abstract: Mountain environments are particularly vulnerable to climatic change effects, giventhat biological organisms in these systems live at specific temperature conditions, thereforeminimal climatic patterns modification affect drastically to the ecosystem at many scales. Theability to succeed in dealing with specific environmental demands by biological organisms canbe achieved with acclimation mechanisms. Assessing lichens response to climatic factors ishighly interesting since they show different patterns unlike to other groups. Poikilohydric natureof lichens allows to inquire into variables like water holding capacity (WHC) and thehydrophobicity of the thallus to understand their occupational patterns in altitudinal gradientsand microsite. WHC (defined as the amount of water per area that the thallus can hold) andhydrophobicity (calculated as the time that water droplets are absorbed by the thallus) weremeasured in saxicolous species with 2 different morphologies and commonly distributed alongthe mountains of Central Argentina: Parmotrema reticulatum, Parmotrema warmingii (foliose)and Usnea amblyoclada (fructicose). We measured WHC in three elevations corresponding tothe distribution range of the species and 3 microsite conditions: north/south aspect with highslope (>90°) and rock outcrops with low slope (