Composition and structure of the bryophyte community of Park Savanna in Marajó Island, Pará, Brazil

Aiming to enrich the knowledge about the flora of savannas, this paper studied the composition and structure of the bryophyte community of Park Savanna areas in Marajó Island - PA. Biological material was collected within 60 100-m² plots equally distributed in the dry season of 2016 and the rainy season of 2017 in five Park Savanna areas (SP-I to SP-V). The composition, density, richness and diversity of species and presence of indicator species were compared between the sampled areas and seasons. The species were classified according to the substrates colonized and ecological groups of light tolerance. Significant differences in SP-V indicated that the area was the main factor influencing the composition of bryophytes (p: 0.0001), with five indicator species. There were also significant differences in density (p = 0.0001168) and richness (p = 0.0001317) of bryophytes between seasons (p-value = 0.3393; p-value = 0.04065; p: 0.1081). There was a predominance of generalist (25 spp.) and corticolous (728 individuals) species, which were widely distributed in the sampled areas. Therefore, the structure of the bryophyte communities was not influenced by seasonality, and this indicates that these plants are adapted to the environmental conditions.

Key words
amazonian savannas; bryoflora; ecology; seasonal precipitation