Análise ambiental de um subsistema de Vereda em unidades de conservação : Reserva Ecológica do IBGE - Recor e Estação Ecológica de Águas Emendadas - ESECAE/DF

Abstract

The studies of Vereda subsystem have been contributing to the knowledge of its origin and evolution, as well as the need for its preservation. Vereda represents an important subsystem of the Cerrado biome, associated generally to the headwater areas from which the maintenance of its balance is critical to the sustainability of water resources in the region. Motivated by an interest in knowing in detail the subsystem Vereda, this thesis aimed to understand the geo-environmental factors related to its origin and its development, as well as the analysis of its geomorphological modeling in two different protected areas of the Federal District (Aguas Emendadas Ecological Station and the IBGE Ecological Reserve). The results contributed to the differentiation of the two Veredas, as the geomorphological position, floristic composition, evolution and environmental changes.From the selection of perpendicular transects to the line of drainage of the two Veredas, distinct zones were recognized based on variations in topographic, soil and vegetation features: seasonal moisture wrap, dry and soaked. For the description of Recor Vereda soils, samples of surface layers were removed in the different zones for the determination of pH; the percentage of organic matter; the availability of P, K, Ca, Mg, Na and Al. The floristic survey was carried out through the expedited pathway method, whose data were the basis for calculating the Sorensen similarity index and the Exotic Environmental Impact index ( IIae). Identified soil types along the strands/slope were Red Latosols, Quartzipsamment (top of the plateau), RedYellow Oxisols (half-slope) and Gelissolos (the valley).The families with the highest number of species were Melastomataceae, Cyperaceae, Asteraceae, Poaceae and Lycopodiaceae. Regarding the evolution (ecological succession) of the analyzed environments it follows that they develop together with the topography and local drainage, whose human intervention can be another cause of environmental changes recorded in this work.