Adauto de Souza Ribeiro

14C Dating and Stable Carbon Isotopes of Soil Organic Matter in Forest–Savanna Boundary Areas in the Southern Brazilian Amazon Region

This study, which was carried out in the southern Brazilian Amazon region (Rondonia state and Humaita, Southern Amazon state), presents and discusses the significance of carbon isotope data measured in soil profiles collected across natural boundaries of forest to savanna vegetation. The main objective of this study was to evaluate the expansion-regression dynamics of these vegetation units in relation to climate changes during the Holocene. (super 14) C data from charcoal, soil organic matter (SOM) and its component humin fraction indicate that the organic matter in the studied soils is essentially Holocene in origin. (super 13) C data indicate that C (sub 3) type plants were the dominant vegetation at all study areas in the early Holocene, and during the entire Holocene, in the forest sites of Central Rondonia state and in the forest site 50 km from the city of Humaita. (super 13) C data also indicate that C4 plants have influenced significantly the vegetation at the transitional forest and the Cerrado (wooded savanna) sites of Southern Rondonia state and the forest ecosystem located 20 km from the Humaita city. These typical C (sub 4) type isotopic signatures probably reflect a drier climate during the mid-Holocene. The (super 13) C records representing probably the last 3000 yr show an expansion of the forest, due to a climatic improvement, in areas previously occupied by savanna vegetation. These results and other published data for the Amazon region indicate that the areas representing todays forest-savanna boundaries have been determined by significant vegetation changes during the Holocene. The boundary between forest and savanna vegetation seems to be quite sensitive to climatic change and should be the focus of more extensive research to correlate climate and past vegetation dynamics in the Amazon region.

Dinâmica do ecótono floresta-campo no sul do estado do Amazonas no Holoceno, através de estudos isotópicos e fitossociológicos

This paper presents a comparative study between organic soil horizons formed in depressions located at the forest/savanna boundary in the Southern Amazon Basin. The influence of the paleovegetation dynamics, based on carbon isotope ( 12 C, 13 C and 14 C) data of soil organic matter (SOM) and plants was evaluated, as well as the present vegetation dynamics, inferred from the modern vegetation structure, composition and phytosociology. The uppermost soil horizon in savanna showed higher total carbon content than in forest. 13 C and 14 C data from soil samples indicated a predominance of C 3 plants in the early Holocene. About 7000 to 3000 14 C yr BP the influence of C 4 plants increased, indicating savanna expansion probably related to a drier climate in the region. Since approximately 3000 14 C yr BP, the carbon isotope data suggest the expansion of forest probably due to a wetter climate. The presence of typical boundary plant species (Sclerolobium paniculatum and Himatanthus sucuuba) in the savanna also suggested present forest expansion.

Phytochemical screening, antinociceptive and anti-inflammatory effects of the essential oil of Myrcia pubiflora in mice

This report aimed to investigate the chemical composition and possible antinociceptive and anti-inflammatory effects of the essential oil from fresh leaves of Myrcia pubiflora DC., Myrtaceae (EOMP), through different experimental tests. The essential oil of M. pubiflora (EOMP) was obtained by hydrodistillation, analyzed by GC-MS, and tested at doses of 25, 50, and 100 mg/kg (i.p.) in three different tests of nociception (acetic acid-induced writhing test, formalin test, and hot plate test) and one test of inflammation (leukocyte migration to the peritoneal cavity) in order to evaluate the motor activity in mice treated with EOMP. The major component of EOMP was caryophyllene oxide (22.16%). This oil significantly reduced the number of writhes in an acetic acid test and the time spent licking the paw at the second phase of the formalin test. Furthermore, EOMP inhibited the carrageenan-induced leukocyte migration to the peritoneal cavity. However, administration of EOMP did not alter reaction time in the hot plate test, and did not affect the motor coordination test. These results indicate antinociceptive and anti-inflammatory properties of EOMP probably mediated via inhibition of inflammatory mediator synthesis or other peripheral pathway.

Florística e estrutura da vegetação arbustivo-arbórea das Areias Brancas do Parque Nacional Serra de Itabaiana/Sergipe, Brasil

The Serra de Itabaiana National Park is distinguished by its phytophysiognomic diversity, among which, a locally known as Areias Brancas (white sands), an open vegetation, ranging from herb-shrub to shrub-tree and classified by some authors as restinga or cerrado, depending on its size. Aiming to characterize and classify vegetational type were selected two sites in Areias Brancas of Serra de Itabaiana National Park and built a list following deposited material in the ASE Herbarium and additional sampling. To the phytosociological study it was used the wandering quarter method, sampling all individuals with trunk circumference (> 15 cm) at breast height (1.30 m). It was verified, at the Areias Brancas, the occurrence of 193 species belonging to 145 genera and 60 families that are mostly represented by herb and shrub species. It is noticeable the high number of species found in Areias Brancas when compared with studies conducted throughout the National Park. There are significant floristic similarity between sampling sites, but structurally the two areas should be considered as different sucessional faces, due to variations in density, height and dominance. Even with plant species in common, the Areias Brancas of the National Park can not be classified as restinga or cerrado for not having common origins for these formations. The Areias Brancas should be considered as an ecological refuge, an azonal vegetation derived from the special conditions of substrate formation.

Birds of the Grota do Angico Natural Monument in the semi-arid Caatinga scrublands of northeastern Brazil

No inventario da avifauna do Monumento Natural Grota de Angico na Caatinga ao norte de Sergipe, Brasil, revelou a presenca de pelo menos 140 especies, incluindo nove endemicas da Caatinga e florestas sazonais adjacentes. Apesar do alcance limitado do estudo (duas expedicoes em Julho e Agosto, 2008), a riqueza de especies registrada no sitio aparentemente pode ser tipica da regiao e do Bioma Caatinga.

Volatile Constituents and Antibacterial Activity From Seeds of Bowdichia virgilioides Kunt

Abstract The essential oil from seeds of Bowdichia virgilioides Kunt (Fabaceae) growing in Brazil was obtained by hydrodistillation and analyzed by GC-FID and GC/MS. This analysis resulted in the identification of 17 components. The main constituents of the essential oil were b-elemene (6.9%), β-caryophyllene (44.1%), germacrene D (7.9%), bicyclogermacrene (6.4%) and caryophyllene oxide (8.9%). The oil was tested for its antimicrobial activity against seven bacteria using the standard gel diffusion method.

Volatile compounds from leaves and flowers of Garcinia macrophylla

Universidade Federal de Sergipe, 49100-000, Sao Cristovao, SE, Brazil, fax 55 79 21056684, e-mail: pclnogueira@uol.com.br; 2) LEEP (Laboratorio de Estudos Ecologicos e Paleoambientais), Departamento de Biologia, Universidade Federal de Sergipe, 49100-000, Sao Cristovao, SE, Brazil; 3) Departamento de Botanica, Instituto de Biologia, UNICAMP, CP 6109, Campinas, 13083-970, SP, Brazil. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 183-185, March-April, 2007. Original article submitted December 20, 2005.

Levantamento etnobotânico da família Cactaceae no estado de Sergipe

As Cactaceae ocorrem em uma ampla diversidade de clima, mas predominam em ambientes semiaridos e de solos rochoso-pedregosos. Familia monofiletica, distribuida em 127 generos e 1500 especies. No APG III, foi subdividida em quatro Subfamilias: Maihuenoideae, Pereskeoideae, Opuntioideae e Cactoideae e integra o segundo grupo botânico mais numeroso da regiao neotropical. No estado de Sergipe ocorrem 11 generos e 26 especies. O objetivo dessa pesquisa foi realizar um levantamento etnobotânico da familia Cactaceae no estado de Sergipe. As cactaceas apresentaram uma grande variedade de usos, a exemplo da ornamentacao, medicinal tradicional, alimenticia e manifestacoes culturais como inspiracao mistico-religioso, producao de poesias, cordeis e cancoes populares. Os resultados foram obtidos por meio de questionario semiestruturado, padronizado e aplicados a 36 individuos moradores de 11 localidades distribuidas nas regioes Leste, Agreste e Alto Sertao. Foi registrado no periodo de 2013 – 2015, 11 especies de cactos aplicadas em 55 usos pelas comunidades locais, as quais foram agrupadas em quatro categorias: medicinal; alimentacao humana e animal; construcao e producao de objetos; ornamental e mistico-cultural. Os cactos cabeca-de-frade, mandacaru, facheiro e palma forrageira tiveram a maior frequencia de citacoes de usos.

Characterization of the understory fuel in 'Serra de Itabaiana' National Park - Sergipe State, Brazil

The National Park ‘Serra de Itabaiana’, as well as other conservation units in Brazil, has commonly suffered ecological losses caused by the wildfires. It is essential to comprehend the characteristics of the fuel to a better understanding of a forest fire behavior and how to extinguish it. In order to do so, 108 plots of 1m 2 were delimitated and all of the surface fuel was collected and weighed. The samples were then removed and placed in an oven to determine the moisture content and the dry weight. It was collected, in the study area, a total of 91.38 kg of dry biomass, corresponding to 8.46t/ha. Considering each vegetation type, the Grass Fields had an average of 3.7t/ha of fuel load, the Forests 12.5t/ha and the White Sands 9.18t/ha. The results suggest that the fuel in white sand areas can ignite more easily; there is greater difficulty of fire ignition in forest areas; and short-lived fires in grass fields.

CARACTERIZAÇÃO DO MATERIAL COMBUSTÍVEL SUPERFICIAL NO PARQUE NACIONAL SERRA DE ITABAIANA – SERGIPE, BRASIL

O Parque Nacional Serra de Itabaiana, assim como diversas outras unidades de conservacao no Brasil, comumente sofrem perdas ecologicas em funcao dos incendios que os atingem. Sendo assim, torna-se essencial compreender as caracteristicas do material combustivel para um melhor entendimento do comportamento do fogo e como melhor combate-lo. Para tal, foram demarcadas 108 parcelas de 1 m2 onde todo o material combustivel superficial foi coletado e pesado. Subamostras foram retiradas e colocadas na estufa para determinar o teor de umidade e o peso da materia seca. No total, foram coletados, dentro da area de estudo, 91,38 kg de biomassa seca, correspondente a 8,46 t/ha. Considerando cada fitofisionomia individualmente, os Campos Graminosos apresentaram uma media de 3,7 t/ha de material combustivel, as Matas 12,5 t/ha e as Areias Brancas 9,18 t/ha. Os resultados obtidos sugerem maior facilidade de ignicao do material combustivel nas areas de Areias Brancas; maior dificuldade de ignicao nas areas de Matas; e incendios de curta duracao nas areas de Campos Graminosos.