Germination of high Andean treeline species of contrasting environments and along elevational gradients in northwest Argentina

CUYCKENS, GRIET AN ERICA; HENSEN, ISABELL; LÓPEZ, VICTORIA LIEN; CELLINI, JUAN MANUEL; RENISON, DANIEL

Neotropical Biodiversity

Taylor & Francis group

Año: 2021 vol. 7 p. 111 - 120

In mountain ecosystems, temperature and precipitation change along elevation and determinethe lower and upper limits of tree species which form forests. Early life performance of treespecies has been assessed along elevational gradients as a proxy for several environmentalvariables. Here, we attempt to answer the following question: How does elevation provenanceinfluence seed mass, viability, and germination of Queñoa (Polylepis spp.)? We worked with fourspecies from two contrasting environments from northwest Argentina. We gathered seeds alongelevation gradients, seeds were weighed, tested for viability (Triphenyltetrazoliumchlorid; TTC)and germination percentage in a controlled environment. The analysis was performed usingGeneralized Linear Models (GLM). We found low germination percentages in all species, probablyrelated to low seed viability. The two species from humid environments had lower seed mass andhigher germination percentages than the two species from dry environments. The effect ofelevational provenance negatively affected the germination of two species, while the other twospecies were not affected. We conclude that although the four species studied belong to thesame genus, their early life characteristics differ between environments and along elevationalgradients according to species. Trends regarding future temperatures suggest increases ingermination for two of our study species and no effects on the other two species.