Topography and edge effects are more important than elevation as drivers of vegetation patterns in a neotropical montane forest.

LIPPOK, D.; BECK, S.; RENISON, D.; HENSEN, I.; APAZA, A.; SCHLEUNING, M.

JOURNAL OF VEGETATION SCIENCE

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2014 vol. 25 p. 724 - 733

1100-9233

Aims: We quantified the effects of elevation, forest edge and topography on habitat conditions (i.e., microclimate, soil properties and forest structure) and plant diversity (i.e., species richness, species evenness and species composition) of tropical montane forest fragments. Location: Tropical montane forestfragments, ?Yungas?, Bolivia. Methods: We measuredmicroclimate and sampled soil properties andwoody vegetationat forest edges and in the forest interior on ridges and in gorges along an elevational gradient of 600 m. We analyzed effects on habitat conditions (i.e. microclimate, soilproperties and forest structure), species richness, evenness and composition with linear mixed effect models and Detrended correspondence analysis (DCA). Results: Changes in habitat conditions were weaker along the elevational gradient than between forest interior and forest edge and between different topographies. Species richness was not affected by any gradient, while species evenness was reduced at forest edges. All three gradients affected species composition, while effects of topography and forest edge were stronger than that of elevation. Conclusions: In general, effects of the 600 m elevational gradient were weak compared to effects of forest edge and topography. Edge effects shifted species composition towards pioneer species, while topographical heterogeneity is particularly important for generating high diversity in montane forests. These results underscore that edge effects are severe in montane forest remnants and that small-scale variation between topographical microhabitats needs to be considered in studies that predict monotonous upslope migrations of plant species in tropical montane forests due to global warming.