Floristic Composition in Secondary Forests Located in a Tropical River Island - Brazil

Fluvial islands are very changeable areas once they have vertical accretion by sediment from the flood as the same time as suffer erosion by channel flow. This factor acts directly over the characteristics of their vegetal cover in terms of composition and successional stages. In an island of the Upper Paraná River a floristic composition survey was performed in order to evaluate the plant succession stage of three forest fragments. The study areas were: Forest 1, an abandoned pasture under successional process over the last 10 years; Forest 2, a 55-year-old primary forest settled over a sand bar; and Forest 3, a fragment of a remaining forest. Floristic composition analysis showed that island soil has disturbed by trampling cattle reflecting on the species settlement throughout the successional process.