Disturbance as a factor in breaking dormancy and enhancing invasiveness of African grasses in a Neotropical Savanna

摘要: The Cerrado is threatened by wildfires and invasive species. We aimed to evaluate in laboratory conditions whether temperature fluctuation at the soil surface, resulting from absence of vegetation due fire, can affect germination Urochloa decumbens U. brizantha, two African grasses. Seeds both species were submitted simulations: 1) during fire 1cm belowground (F); 2) without cover for a month (TF); 3) (F) + 4) control 25oC. After treatments, seeds put germinate 25oC 40 days. had four replicates per treatment three temporal replicates. compared percentage mean time among treatments using ANOVA. TF F+TF highest values results showed that se could not stimulate seed germination, however, they suggest disturbance produces pattern able break dormancy enhance and, consequently, increase invasiveness study Vegetation gaps may become new sites invasion. This information important making management decisions regarding these