The relative effect of altitude and aspect on saxicolous lichen communities at mountain summits from central-west of Argentina

Abstract The altitudinal patterns of lichen communities in gradients are very variable. changes that occur along the mountains depend on climatic factors but also microsite variables such as substrate type and aspect. effect altitude aspect richness, cover composition saxicolous lichens an elevation gradient extra Andean from central-west Argentina was studied. Rock outcrops north south three mountain summits distributed between 2,500 4,500 m.a.s.l. were sampled. Lichen species present a 20 × cm square identified relative measured using digital photography. Richness, analyzed through linear models multivariate analysis. Fifty-eight sites. Richness maximum at middle altitude. Also compositional differences among each summit found. Finally, significant lower altitudes for composition.