Florística de ecossistemas aquáticos temporários na região de Pelotas, Rio Grande do Sul, Brasil

Abstract

Intermittent aquatic ecosystems have biological and economic importance and the most important function of their vegetation is to offer shelter and food to a vast animal diversity. This work aims at carring out the floristic survey of intermittent aquatic ecosystem species, providing tools for their identification. The fieldwork was carried out from August 2011 to August 2012, comprising the four seasons. The analytical keys and data about each species were based on fieldwork and literature revision. The study reported the occurrence of 292 taxa from 55 families. The most representative families were Asteraceae (49 táxons), Poaceae (47) e Cyperaceae (36). The most representative genera were Cyperus L. (9), Senecio L. (9), Eleocharis R.Br. (8). Hygrophila costata Nees e Polygonum punctatum Elliott were the most frequent species, which occurred in all studied areas. The most common life-forms were amphibious (74,5%), amphibious and emergent (12,5%) and emergent (5,8%). Furthermore, 73% of the species were related to water in some way, due to the fact that they are either aquatic species or prefer moist soils. Analytical keys, pictures, occurrence environment, habitat, life form, geographical distribution, flowering and fruiting data are provided.