Laboratorio Of Ecologia E Conservacao

Brasília, Brazil

Laboratorio Of Ecologia E Conservacao

Brasília, Brazil
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Giroldo A.B.,University of Brasilia | Giroldo A.B.,Laboratorio Of Ecologia E Conservacao | Scariot A.,Laboratorio Of Ecologia E Conservacao | Hoffmann W.A.,North Carolina State University
Oecologia | Year: 2017

Over the past 10 million years, tropical savanna environments have selected for small growth forms within woody plant lineages. The result has been the evolution of subshrubs (geoxyles), presumably as an adaptation to frequent fire. To evaluate the traits associated with the shift from tree to subshrub growth forms, we compared seed biomass, germination, survival, resprouting, biomass allocation, and photosynthesis between congeneric trees and subshrubs, and quantified phylogenetic conservatism. Despite large differences in adult morphology between trees and subshrub species, the differences are modest in seedlings, and most of the variation in traits was explained by genus, indicating considerable phylogenic conservatism. Regardless, tree seedlings invested more heavily in aboveground growth, compared to subshrubs, which is consistent with the adult strategy of savanna trees, which depend on a large resistant-fire stem. Subshrub seedlings also invest in greater non-structural carbohydrate reserves, likely as an adaptation to the high fire frequencies typical of tropical savannas. The modest differences as seedlings suggest that selective pressures during early development may not have contributed substantially to the evolution of the subshrub growth form and that the distinct allocation and life history must arise later in life. This is consistent with the interpretation that the subshrub growth form arose as a life-history strategy in which maturity is reached at a small stem size, allowing them to reproduce despite repeated fire-induced topkill. The convergent evolution of subshrubs within multiple tree lineages reaffirms the importance of fire in the origin and diversification of the flora of mesic savannas. © 2017 Springer-Verlag GmbH Germany

Ferreira M.C.,University of Brasilia | Walter B.M.T.,Herbario CEN | Vieira D.L.M.,Laboratorio Of Ecologia E Conservacao
Restoration Ecology | Year: 2015

Topsoil translocation has been used for vegetation restoration throughout the world, but it has been poorly tested within savannas. This study describes Brazilian savanna (cerrado) regeneration for the first 3 years following topsoil translocation. The topsoil was stripped from 2.5 ha of savanna and spread on 1 ha of an abandoned laterite quarry in the Federal District, Brazil. We assessed vegetation structure and species composition in 18 circular plots (3.14/m2) after 5 and 15 months and in 30 circular plots after 37 months. In the last floristic survey, the coverage of herbs was estimated using the step-point method. To verify the source of regeneration, a total of 181 shrubs and trees were excavated over the first 2 surveys. After 3 years, 24, 40, and 21 species of herbs, shrubs, and trees, respectively, had been recorded by the surveys. Of the 33 families found, Fabaceae, Poaceae, and Asteraceae were the most representative. At 5 and 15 months, 91 and 83% of the individuals (shrubs and trees combined) were derived from resprouting, respectively. Shrub and tree stem density reached 3.2/m2 at 5 months, but declined to 0.5/m2 at 37 months. By the final survey, native and exotic grasses completely covered the ground. Topsoil translocation was effective for the propagation of native herbs, shrubs, and trees, despite the need to control invasive grasses. The large number of shrub and tree resprouts from roots suggests that the bud bank is an important component of the topsoil for savanna restoration. © 2015 Society for Ecological Restoration.

de Oliveira W.L.,Laboratorio Of Ecologia E Conservacao | de Medeiros M.B.,Laboratorio Of Ecologia E Conservacao | Moser P.,Santa Catarina State University | Pinheiro R.,Santa Catarina State University | Olsen L.B.,University of Brasilia
Acta Botanica Brasilica | Year: 2011

The objective of this research was to study the population structure of Hymenaea courbaril in two fragments of non-flooded gallery forests with different degrees of human impact. The research hypothesis was that populations present different size classes and number of individuals between fragments and that recruitment is related to understory light. As a climax species that requires light, and a species that is adapted to a variety of environments, there would probably be a higher abundance and regeneration of H. courbaril in a fragment that has more light. Twenty-five plots (10 x 20 m) were set in two fragments using transects between the forest edge and the stream bank. The seedlings were recorded within each plot by means of four subplots (2 x 2 m) in a central line along the plots. Within the understory the photosynthetic active radiation was determined and the transmittance values (T%) were calculated by measuring the sunlight in an open field. In both fragments, more individuals were concentrated in the smaller size classes. However the popula- tion sizes in both fragments were not adjusted to the negative exponential distribution (reversed J curve). A linear regression analysis indicated that both the diameter and height of young individuals were related to transmittance (T%) (F=11,58-14,82 (1,40); p<0,01). The lower abundance of juvenile individuals in the disturbed fragment might be due to recent and frequent fires. In spite of the higher abundance of young individuals in the preserved fragment, which has more undisturbed canopy and lower light conditions, in the understory these young individuals had size classes similar to the seedlings. This result suggests that H. courbaril is able to regenerate and to recruit in shaded environments. However, the growth of H. courbaril might be constrained by these lower light conditions.

Vieira D.L.M.,Laboratorio Of Ecologia E Conservacao | Coutinho A.G.,Laboratorio Of Ecologia E Conservacao | Coutinho A.G.,University of Brasilia | Da Rocha G.P.E.,Laboratorio Of Ecologia E Conservacao
Restoration Ecology | Year: 2013

Tropical dry forest tree species are recognized for their high resprouting ability after disturbance. We tested whether species that commonly produce root and stem suckers can be propagated by large stem and root cuttings, a useful method for landscape restoration programs. We performed four experiments: (1) In a greenhouse, we tested the propagation of six species using large stem cuttings collected from early successional sites. We used the following treatments: (i) dry season collection and planting; (ii) dry season collection, storage in humid soil, and wet season planting; (iii) wet season collection and planting; and (iv) wet season collection and planting after treatment with commercial NAA auxin. (2) Stem cuttings of Myracrodruon urundeuva were planted in a pasture during the rainy season after either NAA, IBA, or no auxin treatment. (3) As a control experiment, we also planted cuttings of Spondias mombin, a species known for successfully regenerating from cuttings. (4) Root cuttings of six species were collected in recently plowed pastures and planted in the greenhouse with and without treatment with NAA auxin. No root cuttings rooted. Only M. urundeuva and Astronium fraxinifolium stem cuttings rooted. Maximum success was obtained for stem cuttings collected and planted in the dry season (23%). Only 13% of M. urundeuva had sprouted by the 15th month of the field experiment. As a result, large cuttings are not recommended for propagation of the studied species. Future studies should include development of suitable methods of root harvesting and prospection of traditional knowledge for species selection. © 2012 Society for Ecological Restoration.

Lima I.L.P.,University of Brasilia | Scariot A.,Laboratorio Of Ecologia E Conservacao | Giroldo A.B.,University of Brasilia
Agroforestry Systems | Year: 2016

Large-scale commercial cattle ranching is the main driver of deforestation in the world, with several negative environmental and social impacts. To meet the growing demand for animal products, silvopastoral systems (SPS) can be an alternative as they have greater biodiversity and offer more environmental services than conventional cattle ranching systems. This paper aims to describe the implementation of SPS by traditional farmers in a rural settlement in southeastern Brazil, and the impacts on biodiversity of native plants. SPS were implemented by farmers in three selected areas that were cleared with a tractor. The impacts on the community and populations of native plants were estimated through vegetation sampling before and after the implementation of the SPS. Direct observations and semi-structured interviews were conducted to describe the implementation of the system and to understand the criteria employed to spare species, to manage native plants and the advantages of these systems according to farmers’ perceptions. Before the implementation, 1038 trees from 50 species and 29 botanical families were surveyed in the three areas. The tractor cleared on average 72 % of the trees, decreasing the number of trees ha−1 from 692 to 180 and reducing tree richness in 43 %. On average, 89 % of the removed trees had diameter ranging from 5 to 10 cm, indicating farmers’ preference in sparing the thickest trees. Farmers also spare useful species that have socio-economic importance, such as timber, fruit trees, fodder and medicine. According to the farmers, the advantages of the SPS are the high concentration of useful species, the environmental services provided and the increase in livestock production. The system described has great potential to ensure food security, generating socio-economic benefits for farmers and contributing to biodiversity conservation. © 2016 Springer Science+Business Media Dordrecht

Lima I.L.P.,University of Brasilia | Lima I.L.P.,Laboratorio Of Ecologia E Conservacao | Scariot A.,Laboratorio Of Ecologia E Conservacao | Giroldo A.B.,University of Brasilia | Giroldo A.B.,Laboratorio Of Ecologia E Conservacao
Economic Botany | Year: 2013

Sustainable Harvest of Mangaba (Hancornia speciosa) Fruits in Northern Minas Gerais, Brazil. The harvesting of non-timber forest products can contribute to conserving biodiversity and improving quality of life for rural communities. However, overexploitation can generate negative impacts on harvested populations, demanding the establishment of sustainable management practices. We estimated the maximum sustainable harvest of Hancornia speciosa Gomes (Apocynaceae) fruits in a savanna in northern Minas Gerais state, Brazil. The structure and population dynamics were analyzed in 70 permanent plots (20 x 50 m) in the years 2008-2011. A matrix population model based on life stages (seedlings, saplings, adults 1, adults 2) was used to calculate the population growth rate (λ), the stable stage distribution and the elasticity, and to simulate the effects of different fruit harvesting levels. The population growth rate (λ) value was 1.02 (CI95% 0.98 to 1.05), the maximum sustainable fruit harvest rate was 87%, and the elasticity analysis indicated that survival of the larger-size adults is the most important parameter to maintain the population. Apparently, the H. speciosa population is stable, which may indicate that the current harvesting level is not affecting population regeneration. However, other natural or anthropic disturbances, such as charcoal production and fire, can increase adult mortality, leading to population decline. © 2013 The New York Botanical Garden.

Lima I.L.P.,University of Brasilia | Lima I.L.P.,Laboratorio Of Ecologia E Conservacao | Scariot A.,Laboratorio Of Ecologia E Conservacao | de Medeiros M.B.,Laboratorio Of Ecologia E Conservacao | And 2 more authors.
Acta Botanica Brasilica | Year: 2012

The conserva- tion and sustainable use of biodiversity requires knowledge about the native vegetation and how local people use available natural resources. The aims of this study were to test the ecological appearance hypothesis and to survey the diversity of uses and distribution of knowledge about useful plants in a tradicional community (Geraizeiros) in the municipality of Rio Pardo de Minas, in northern Minas Gerais, Brazil. Caryocar brasiliense Cambess., Hancornia speciosa Gomes, Sclerolobium paniculatum Vogel and Pterodon emarginatus Vogel presented higher use (0.7 to 1.8) and phytosociological importance values (1.31 to 36.98). The use diversity (H' = 1.13 to 1.26) and plant diversity in the environment (H' = 3.11) were low. Men demonstrated more knowledge of useful species than women and there were no significant differences related to informant age. A positive relationship was found between utility and plant availability in the environment, confirming the ecological appearance hypothesis. These results may contribute to the conservation of the cerrado savanna, the livelihood of local people and the establishment of management strategies based on local demands and priority species.

Giroldo A.B.,University of Brasilia | Giroldo A.B.,Laboratorio Of Ecologia E Conservacao | Scariot A.,Laboratorio Of Ecologia E Conservacao
Biological Conservation | Year: 2015

Human activities may determine the demography and the conservation of non-timber forest products (NTFP) in the tropics. The response of plant populations to anthropogenic factors can be assessed on plant demography at landscape level and used for decision-making in conservation and management strategies. We evaluated the influence of anthropogenic and ecological variables on the demography of the tree Caryocar brasiliense, the most harvested fruit species of the Brazilian Cerrado. For this, we assessed how size class distribution and density of plant life-stages of 34 populations were associated with land use and management over a large geographical area. Our results indicate that land use and management affects Caryocar demography. Most population size class distributions significantly fitted to reverse J-shaped curve, indicating good recruitment, and low fit populations were generally subjected to intense cattle ranching. Cattle ranching was also negatively associated with seedling and sapling densities and vegetation thinning with seedling, juvenile and adult densities. Current fruit harvesting levels are not affecting recruitment at the landscape level. We conclude that the negative effect of cattle and vegetation thinning can be mitigated by increasing the rotation time between areas and intervals between thinning events and that current fruit harvesting pressure on Caryocar populations is sustainable across landscape. The social and economic importance of this species is an ecological asset that can be used for the development of public policies promoting multiple uses of habitat remnants to ensure that the strategy of conservation under use is carried out. © 2015 Elsevier B.V..

Silva R.R.P.,University of Brasilia | Oliveira D.R.,EMATER DF | da Rocha G.P.E.,Laboratorio Of Ecologia E Conservacao | Vieira D.L.M.,Laboratorio Of Ecologia E Conservacao
Restoration Ecology | Year: 2015

Direct seeding is a promising technique for ecological restoration, but it has been poorly studied in neotropical savannas. Different types of plant cover (no cover, crops, or green manure) and fertilization (unfertilized, synthetic fertilizer, or poultry litter) were used to verify if survival and growth of different tree species after direct seeding could be enhanced by the use of any combination of these techniques. Seedling emergence, establishment, and growth were followed for 2 years for six savanna tree species sown in an agricultural field in Central Brazil. Germination was high (52%, on average) for Anacardium occidentale, Aspidosperma macrocarpon, Hymenaea stigonocarpa, Dipteryx alata, Eugenia dysenterica, and Magonia pubescens. Six additional species were planted, but less than 5% of these seeds germinated. Crops (60% shade) did not affect seedling survival and biomass compared with the control treatment, supporting the use of this strategy during the initial phase of restoration to involve farmers in the process. In contrast, the excessive shading (95%) from the green manure treatment decreased the survival of two species and the growth in biomass and diameter of five species, especially when combined with fertilization. Seedling growth was very slow throughout the experiment, requiring extended weed management. This study supports the use of direct seeding of the studied species for savanna restoration, but methods could be improved to include a larger number of species. © 2015 Society for Ecological Restoration.

da Silva P.A.D.,University of Brasilia | Scariot A.,Laboratorio Of Ecologia E Conservacao
Acta Botanica Brasilica | Year: 2013

The fruits of the palm Butia capitata are harvested from wild populations. A lack of knowledge of their ecology has hindered the establishment of sustainable management practices. We investigated fruit biometric parameters, yield and phenology in two populations of B. capitata in the cerrado (savanna) in the north of the state of Minas Gerais, Brazil, at two study sites: in the communities of Mirabela (Fazenda Baixa site, studied from December 2006 through December 2007) and Campos (studied throughout 2007). Overall, adult palms produced an annual average of 7.6 leaves. At the Fazenda Baixa site, the mean annual number of infructescences was 4.9, compared with only 1.6 at the Campos site, and the annual yield was 197-373 and 145-468 fruits per tree (in 2006 and 2007, respectively), compared with 67-247 at the Campos site. Reproductive events were seasonal and influenced by rainfall distribution. Typically, inflorescences and immature infructescences appeared in the dry season, mature infructescences appearing in the rainy season. Inflorescence production and fruit biometric parameters differed between the two populations. Fruit yield correlated with height and leaf biomass. We found that B. capitata fruits, which are highly perishable, should be harvested when nearly-ripe and remain attached to the infructescence during transport. Our findings have important implications for the development of strategies for sustainable management and in situ conservation of populations of this species.

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