The moist grassland community vegetation of the Cerrado is one of the physiognomies where the water table is superficial throughout the year. It generally occurs bordering the gallery forests, located between these forests and the well-drained Cerrado physiognomies. The aim of this study was to investigate the phytosociological structure of the herb-subshrub layer in a moist grassland at Água Limpa farm, Brasília, DF, and assess possible changes in species composition and cover, at different times throughout a 13-month period, after a fire. An area of 400×400 m was subdivided into four sections of 200×200 m and the transects were randomized. The line intercept method was adopted, where each line was divided into sections of 1 m. A total of 84 species in 54 genera and 24 families was found. Sørensen similarity indices were low when the four transects were compared, from 0.26 to 0.55%, probably due to soil and moisture variation among sampled sections. TWINSPAN classification indicated that transects with a superficial water table year round and high organic matter content were different floristically from those on soils having seasonal variation of the water table level. Similarity indices between floristic composition and cover found in the transects during different sampling occasions were high, due especially to the small variation in cover values of the most important species over the year.
herbaceous layer; Cerrado; fire; line intercept method; savanna
