Geographic distribution of bryophytes in Maranhão, Brazil: an analysis of the known to understand the unknown

Abstract

We analyzed the species richness and collection density of Maranhão's bryoflora and the main vectors of anthropogenic pressure and indicated the priority areas for new sampling aimed at conserving the species. We created a database from the bryophyte collection registered in the Prof. herbarium. Aluízio Bittencourt (HABIT), from the Universidade Estadual do Maranhão/UEMA campus Caxias, in addition to collections with records of specimens obtained from the Virtual Herbarium, GBIF and SpeciesLink. Species identification and information on geographic distribution were confirmed for the records considered in this study, supporting analyzes of richness (species) and density (occurrence of collections). For the collection density, the kernel density estimator was used and to identify areas of endemism, the Geographic Interpolation of Endemism (GIE) method was used. 3,727 collection records were analyzed, observing that most areas of the state do not have bryophyte collection records (65%). In the 35% of areas collected, we observed that the distribution pattern was heterogeneous, with many areas presenting few species, and few areas presenting many species. Only four areas had collection density considered good, providing areas of species endemism. Agricultural activities are the main threat vectors for bryophytes in Maranhão. It is recommended that collection efforts be carried out in the North, West, Center and South regions of Maranhão, where there are areas with low or no records of bryophytes.