Efeitos da invasão biológica por Eragrostis plana Nees na resiliência ecossistêmica: implicações para a restauração do estrato herbáceo em formação parque

• Ano de defesa: 2024
• Autor(a) principal: Camargo, Betina
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Santa Maria; Brasil; Engenharia Agrícola; UFSM; Programa de Pós-Graduação em Engenharia Agrícola; Centro de Ciências Rurais
• Palavras-chave em Português: Banco de sementes do solo; Invasão biológica; Bioma Pampa; Restauração ecológica; Efeito do fogo; Capim-annoni; Unidade de conservação; Soil seed bank; Biological invasion; Pampa biome; Ecological restoration; Fire effect; Eragrostis plana; Conservation unit; CNPQ::CIENCIAS AGRARIAS::ENGENHARIA AGRICOLA
• Link de acesso: http://repositorio.ufsm.br/handle/1/33090

The Pampa biome faces serious threats due to the invasion of the exotic African grass Eragrostis plana Nees. This study aimed to assess the impacts of this invasion on ecosystem resilience by analyzing the soil seed bank and natural post-fire regeneration in areas of Park Grassland in southern Brazil. In Chapter 1, the seed bank was studied in four areas with different levels of E. plana invasion. Ten soil samples (25 cm x 25 cm x 5 cm) were collected in each area, without aerial material, and evaluated biweekly in a shade house at UFSM. The analysis of floristic composition, richness, and density, using the seedling emergence method, revealed the presence of the invasive species even in locations where it was not detected in the established vegetation, highlighting its high invasive potential. In Chapter 2, the effect of fire on the herbaceous layer in areas invaded by E. plana was investigated. Thirty-six 1 m² fixed plots were installed in burned areas and another 36 in unburned areas. The variables analyzed were: ground cover, plant richness, and abundance. The results indicated that while fire temporarily reduces E. plana cover, the species recovers quickly, suggesting that fire alone is not sufficient to control the invasion. However, seasonal analysis identified post-fire management windows that, combined with control techniques, may be more effective in promoting the restoration of native vegetation. It is concluded that continuous monitoring and integrated management strategies are essential to ensure ecosystem resilience and the preservation of native biodiversity in Park Grasslands invaded by E. plana.