Evolução paleoambiental em salinas da Nhecolândia no holoceno superior, Pantanal sul-matogrossense

Abstract

The region of Nhecolândia has a distinct landscape when compared to other Pantanal regions since it bears areas with ponds limited by Cordilheira forest, sand stripes and that may be connected by ebb tides. Some of these pounds have salinity indexes that may reach the hyper-salinity. It is believed that the origin of these lakes was in the last 5 thousand years. Here, it is presented palinological and organic geochemistry analysis of sediments collected at two saline pounds at the region of Nhecolância, MS. The obtained data indicate that at 3.410 years BP the vegetation surrounding the pound was composed by Bromeliaceae, Asteraceae, Arecaceae, Amarantaceae and Nymphaceae. Registers of Cabomba sp. at 2.300 years BP show that the salinity indexes still allow the existence of macrophytes inside the pound. Beyond 1.200 years BP, the increasing in the quantity of COT associated to grains that indicate seasonal floodable forests, suggest the establishing of vegetation similar to the current one.