Diversidad de costra biológica relacionados con la elevación en un matorral montano del sur del Ecuador

Abstract

Abstract: Montane scrublands are characterized by having vascular plant species that do not exceed five meters in height, as well and in addition to lichens, bryophytes and cyanobacteria that together make up the biological soil crust (CBS). The CBS in this type of ecosystems fulfills ecological functions related to the water and nutrient cycle. There are important advances regarding the patterns of richness and composition of CBS in temperate regions, however, in tropical regions such as Ecuador there are few reports. The objective of this research focused on determining a pattern of richness and composition along an altitudinal gradient of montane scrub south of Ecuador. For this three elevations gradients were selected (gradient 1: 2100m, gradient 2: 2300m, gradient 3: 2500m), at each elevation three plots were made, within each plot 20 sub-plots were established giving a total of 180 sampled sub-plots. We analyzed changes in richness and elevation with generalized linear model (GLM) and for species composition a non-metric multidimensional scaling analysis (NMDS) and multivariate analysis based on permutations (PERMANOVA). We recorded 56 species (36 lichens, 17 bryophytes, 3 cyanobacteria), with 26 species in gradient one, 31 in gradient two and 26 in gradient three, which allowed us to point out that species richness was higher at intermediate elevations and that the composition showed significant differences in the three elevation gradients. Therefore, the elevation notoriously affected the richness and species composition of CBS, becoming an essential contribution to the conservation of montane scrub in Ecuador.