Beta diversity analyses reveal distinct bryophyte community assemblages on different substrates in Neotropical seasonally dry forest fragments of the Colombian Caribbean

Abstract

ABSTRACT Introduction Bryophytes in Colombia mainly inhabit humid forest, but some species have been found in fragments of dry forest in Montes de María in the Colombian Caribbean. However, it is unknown whether bryophytes have shaped communities associated with different substrates. Methods Bryophyte diversity was surveyed in nine plots at three localities: Chalan, Colosó and Toluviejo. To determine whether different communities were associated with particular substrates, we used the alpha diversity (Hill numbers), beta diversity and Bray–Curtis dissimilarity indices. Bray–Curtis dissimilarity was also used to determine whether these communities were the result of turnover or nestedness. Key results A total of 30 species of moss and 11 species of liverwort were identified. The most species-rich families were Neckeraceae and Pottiaceae for mosses and Lejeuneaceae and Frullaniaceae for liverworts. These plants inhabit bark, rock, soil and decaying wood substrates. Bark and rock were the most species-diverse substrates at all localities; soil and decaying wood were less diverse. Two main assemblages were detected, both shaped mainly by turnover: (i) bryophytes on bark/decaying wood and (ii) those on rock/soil. However, bryophytes on rock and soil formed two different communities in Chalan and Colosó, and bryophytes on bark/decaying wood were the most diverse community in Montes de María. Conclusions Beta diversity analyses revealed communities associated with different substrates and apparently shaped by environmental filters and dispersal limitations. The analyses thus provide important ecological information on bryophyte ecology. However, more detailed information is required to understand how these communities have arisen.