Keiko Fueta Pellizzaro’s research while affiliated with University of Brasília and other places

Este artigo apresenta o projeto Jardins de Cerrado e suas atividades iniciais. Desde 2015, fazemos expedições em busca de plantas (o chamado planthunting), cultivo de ervas e arbustos nativos, experimentos científicos e jardins experimentais. Testamos metodologias de projeto e implantação, baseadas nos jardins naturalistas contemporâneos. O objetivo do projeto é promover a criação de uma linguagem paisagística que expresse o Cerrado, a savana mais rica em biodiversidade e mais ameaçada do planeta, colocando em evidência as ervas e arbustos que compõem a base de suas formações vegetais. Consideramos que jardins são ferramentas estratégicas para a conservação da biodiversidade, ao contribuir para o aumento da percepção e da valorização da flora nativa pelo público em geral.

Tropical grassland-savanna mosaics are threatened globally, but they are challenging to restore because highly competitive pasture grasses inhibit recovery and are not shaded out by the patchy tree cover. We analyzed the outcomes of restoration projects and experiments established over four years in 55 ha of abandoned pastures dominated by invasive C4 grasses within the Neotropical savanna, Central Brazil. We tested the efficacy of direct seeding native grasses, forbs, shrubs and trees in reducing invasive grass cover and increasing native ground cover. We performed a series of experiments aimed at answering questions about the effect of seeding density, soil plowing to control invasive grasses, life form of ground cover species (grass, forb or shrub) and soil type on restoration outcomes. Relative native cover reached 34 ± 3% three rainy seasons after the first seeding experiment. Higher seeding densities and more soil plowing repetitions increased relative native cover. Soil type interacted with the life form of ground cover species to strongly influence relative native cover; two years after seeding, the highest relative native cover was achieved in rocky soils seeded with grasses (78 ± 6%) and the lowest was for seasonally waterlogged soils seeded with shrubs (15 ± 4%). Direct seeding can effectively establish many native Neotropical savanna species of different life forms with better restoration outcomes on rocky soils and with higher seeding densities. Further research is urgent to improve restoration methods, especially to control invasive grasses, to be able to achieve the large-scale restoration targets set internationally.

The coexistence of grasses, herbs, shrubs and trees characterizes savannas; therefore, to restore such ecosystems one should consider re-introducing all these growth forms. Currently, little is known about field establishment of most “Cerrado” (Brazilian savanna) species that could be used for restoration purposes. Most knowledge on restoration is focused on planting seedlings of tree species from forest physiognomies. Alternatively, direct seeding can be an appropriate method to re-introduce plants of different life forms to restore savannas. We evaluated the initial establishment success under field conditions of 75 “Cerrado” native species (50 trees, 13 shrubs, and 12 grasses) in direct seeding experiments in four sites in Central Brazil for 2.5 years. For that, we tagged and measured tree and larger shrub species and estimated ground cover by small shrub and grass species. Sixty-two species became established (42 trees, 11 shrubs and 9 grasses) under field conditions. Thirty-eight of the 48 tagged species had relatively high emergence rates (>10%) and 41 had high seedling survival (>60%) in the first year. Among grasses and small shrub species, Andropogon fastigiatus Sw., Aristida riparia Trin., Schizachyrium sanguineum (Retz.) Alston, Lepidaploa aurea (Mart. ex DC.) H.Rob., Stylosanthes capitata Vogel, S. macrocephala M.B.Ferreira & Sousa Costa, Achyrocline satureioides (Lam.) DC. and Trachypogon spicatus (L.f.) Kuntze had the greatest initial establishment success (up to 30% soil cover). The data on harvesting period, processing mode and field establishment for these 75 species can be readily used in restoration efforts in the “Cerrado”.