Hortência Soardi Maricato
Abstract:
Floodplain ‘murundus’ present hydromorphic soils, with 'monchões' of varying sizes in both height and diameter. Usually these 'monchões' have an association with termite mounds and woody vegetation of Cerrado sensu stricto. Nowadays with the expansion of agricultural frontiers floodplain ‘murundus’ are disappearing or suffering a high degree of disturbance, with the implementation of drains for runoff from the soil. The main aim of this study was to evaluate the impact of the implementation of drains in the structure of the woody component in floodplain ‘murundus’, comparing the structure of vegetation in two different situations: near and far from the drains. We studied all vegetation with woody plants equal or greater than three cm (db ≥ 3 cm) in height and 30cm of soil. The phytosociological parameters were calculated: density, dominance and relative frequency and importance value. We also calculated the Shannon diversity index (H ') and evenness (J'). Were established 20 permanent plots of 20 x 50 m, 10 plots of 0-20 m of drains and the other 10 between 200-400m away from the drain (interior), totaling a survey of two hectares. Recorded 47 species and 23 families distributed in 461 individuals. With a total density of 230.5 ind.ha-1 and total basal area estimated 1.331 m2.ha-1. The diversity index was estimated as H’ = 3.18 and equability J' = 0.85. The woody vegetation present in floodplain ‘murundus’ are suffering interference from the drains in the area, these drains favor runoff thereby modifying the soil structure and vegetation of the site, one of the evidence refers to the development of vegetation between the bases of ‘monchões’ near from drains.
