"Soil management and exotic grasses control to Neotropical Savanna restoration: testing applicable large-scale techniques."
Biological invasions; Direct seeding; Ecological restoration; Exotic grasses; Invasion control; Invasive grasses; Neotropical savanna.
Savannas are widely distributed throughout the tropics, with trees, shrubs and grasses coexisting naturally. The conversion of native vegetation, the introduction of exotic species and changes in the disturbance regime are degradation factors in tropical savannas. Invasive exotic grasses (IEG), introduced in planted pastures, are a degradation factor at the place of introduction and in nearby areas. Large biomass production, abundant seed production, and high resprouting and/or germination abilities are IEG characteristics that make their control difficult in neotropical savanna restoration projects. The objective of this work is to evaluate different IEG control and soil management techniques for native plants establishment and control IEG re-invasion in areas under restoration by direct seeding in the Cerrado. Measurement of local vegetation and soil samples, followed by a nursery germination experiment, will allow comparison of successive plowing and topsoil removal for IEG seed bank control in ecological restoration areas on exotic pastures. Harrowing and topsoil removal are also part of a factorial experiment combining such techniques with the application of ferrous sulfate and/or chemical control of IEG, to evaluate which technique, or combination of techniques, better promote IEG control and the development of native plants post direct seeding. This work will be developed between 2022 and 2026, with it, we hope to provide important information for decision making in different Cerrado restoration projects.