Herbáceas aquáticas do município de Parintins, Amazonas, Brasil

Abstract

Aquatic herbaceous plants constitute an important plant group in the floodplains of the Amazon due to their high primary productivity and biomass production and directly reflect the physical and chemical characteristics of the waters in which they are located. They have diverse ecological functions, serving as shelter and food for aquatic and terrestrial organisms. Its studies have contributed to the conservation of biodiversity and water resources. However, research on aquatic herbaceous plants in the North of Brazil is still incipient despite corresponding to around 50% of the Brazilian territory. In Amazonas state, these studies are even scarcer, even though it is a state that is bathed by some of the largest rivers in the world. Therefore, the objective of the study was to carry out a survey of aquatic herbaceous present in the municipality of Parintins, Amazonas state. For this, 11 muddy water sampling sites and 6 black water sampling sites were sampled in the municipality of Parintins. The collected material was stored in the Parintins Herbarium (HPIN). Was recorded 199 collected species, distributed in 121 genera and 52 families. The richest families in terms of species richness were Fabaceae Lindl. (34 species), Poaceae Barnhart (26), Cyperaceae Juss. (19), Onagraceae Juss. (10), Asteraceae Bercht. & J. Presl (9) and Euphorbiaceae Juss. (8) the others present one, two, three or four species each. Regarding life forms, (40%) are amphibious herbaceous, (26%) terrestrial herbaceous, (15%) emergent herbaceous, (7%) climbing herbaceous, (5%) fixed floating herbaceous with floating stems, (4%) free floating emergent herbaceous plants, (2%) fixed floating herbaceous plants with floating leaves and (1%) free floating submerged herbaceous plants. The floodplain sampling sites (muddy water) showed low floristic similarity with the igapó sampling sites (black water), with no species occurring in all the sampled points. This is the first floristic survey study of aquatic herbaceous plants in the municipality of Parintins, where more than 100 species were included in the list of aquatic plants for the state of Amazonas. A lack of information on aquatic plants throughout the southern region of the state was observed. It is suggested to expand floristic survey studies of aquatic herbaceous plants in Amazonas state to make up for the lack of data on this group of plants in priority areas that are rarely collected in the state.