Marcelo Brilhante de Medeiros

Angiosperms from the Araripe National Forest, Ceará, Brazil

This study provides a species list of the angiosperms from the Araripe National Forest (ANF) in the south part of Ceara state, northeastern Brazil. The floristic survey recorded 188 species from 55 Angiosperm families. The most species-rich families were Fabaceae (31), Rubiaceae (17), Asteraceae (14), Bignoniaceae (10), Myrtaceae (9), Euphorbiaceae (7), Apocynaceae and Malpighiaceae (7) and Annonaceae and Solanaceae (5). The flora of the ANF is composed of typical species from the vegetation physiognomies of Cerrado sensu lato such as cerradao and cerrado sensu stricto and it is influenced by the northeastern phytogeographic Cerrado province. Furthermore, there are influences of ecotones between these physiognomies, seasonal forests and carrascos within the Caatinga biome. In addition to four threatened species that were recorded, the ANF also harbors species that represent important incomes for local communities because of the non-timber forest products, such as Dimorphandra gardneriana Tul. and Caryocar coriaceum Wittm.

Efeito de incêndios florestais na estrutura e composição florística de uma área de cerrado sensu stricto na fazenda Água Limpa-DF

This research aimed to evaluate the effect of fire on the structure and floristic composition of a 10 ha cerrado sensu stricto area located at the Ecological and Experimental Reserve of the University of Brasilia, Fazenda Agua Limpa-FAL. Two assessments were conducted in the area: the first, after the area had suffered a criminal fire in 1999, and the second in 2002. A sample of four 20 x 50 m permanent plots was assessed. All individuals with stems 5 cm diameter at 0,30 m (Db) from the ground level were registered, and had their Db and total height measured. Density, basal area, frequency and value of covering index were calculated for the two assessments. The floristic similarity between the two surveys was evaluated for qualitative data (presence and absence of species) based on the Sfrensen Index. Few changes were observed in the floristic composition of the community during the studied period. There was an increase of 125% in density by hectare from 1999 to 2002. A high similarity (Sfrensen Index equal to 0.68)was found between the two assessments while diversity (Shannon Index) was small (about 2.5). This value is smaller than those found in natural areas of the Cerrado sensu stricto at Fazenda Agua Limpa, although it is common in areas with disturbances. Three years after fire 13 new species were verified in the area.

Avaliação das condições de trabalho, treinamento, saúde e segurança de brigadistas de combate a incêndios florestais em unidades de conservação do Distrito Federal: estudo de caso

RESUMO – Este estudo teve como objetivo avaliar as condicoes de trabalho, treinamento, saude e seguranca dos brigadistas de combate a incendios florestais no Distrito Federal. A pesquisa foi realizada nas Unidades de Conservacao da Fazenda Agua Limpa, Reserva Ecologica do Instituto Brasileiro de Geografia e Estatistica e Instituto Jardim Botânico de Brasilia. A coleta de dados foi feita com a aplicacao de um questionario em forma de entrevista individual. Participaram da avaliacao todos os 53 brigadistas das Unidades de Conservacao. De acordo com os resultados, a brigada do Jardim Botânico de Brasilia tinha significativo porcentual de treinados (92,8%), todos com cursos de primeiros socorros, e um alto porcentual de trabalhadores com problemas de saude (33,3%). Os brigadistas da Reserva Ecologica do IBGE exerciam, em sua grande maioria, o trabalho por gosto pela atividade (84,6%), eram bem treinados (92,3%) e todos participaram de cursos de primeiros socorros, sendo o porcentual de acidentes o mais baixo (7,7%). Na brigada da Fazenda Agua Limpa foram encontrados os menores porcentuais de treinados (39,1%), maiores porcentuais de acidentes (17,4%), menores porcentuais de pessoas que exerciam a funcao por gosto pela atividade (30,4%) e menores porcentuais de pessoas com problemas de saude (8,7%). A grande maioria dos brigadistas nas tres Unidades de Conservacao ressaltou a questao da necessidade de regulamentacao das brigadas e atentou para a insatisfacao quanto aos equipamentos de protecao individual utilizados e inadequada reposicao.

Vegetation types of the upper Madeira River in Rondônia, Brazil

We characterize the vegetation types of the upper basin of the Madeira River in the Brazilan state of Rondônia, a biodiverse region with elevated rates of habitat loss. Vegetation and environmental parameters were recorded from 37 observation points distributed along and near a 160 km stretch of the Madeira River and representing the range of regional environments. Analysis of structure and floristic variables, as well as associated edaphic attributes and water table fluctuation, permitted recognition of five main vegetation types and seven subtypes. Open Ombrophilous Forest was the most frequently encountered vegetation type and occurred on well-drained, nutrient-poor soils, whereas Dense Ombrophilous Forest was seldom recorded. Alluvial Ombrophilous Forests (várzea) were found along a narrow strip of land along the banks of the Madeira River on the most fertile soils in the study area. Semideciduous Forests were found on small areas of rocky outcrops with shallow soils and reduced water availability during the dry season. Campinaranas, which range from open savanna physiognomies to closed canopy forests, were found to be a key environment in the lowlands south of the Madeira River on silty hydromorphic soils, where they harbor a peculiar flora tolerant of flooding during the rainy season. Our classification of the main vegetation types in the upper Madeira River illuminates a high degree of floristic and environmental heterogeneity in a highly threatened region. Our results will be useful for designing conservation strategies aimed at protecting the full range of floristic diversity present in the region.ResumoCaracterizamos os tipos de vegetação do alto rio Madeira no estado de Rondônia, uma região biodiversa mas com taxas elevadas de perda de habitat. Parâmetros de vegetação e ambientais foram registrados em 37 pontos de observação distribuídos ao longo de um trecho de 160 km do rio Madeira, representando a gama de ambientes da região. A análise das variáveis estruturais e florísticas, bem como dos atributos edáficos associados e a flutuação do lençol freático, permitiram o reconhecimento de cinco principais tipos de vegetação e sete subtipos. A Floresta Ombrófila Aberta foi o tipo de vegetação mais freqüentemente encontrado e ocorreu em solos bem drenados e pobres em nutrientes, enquanto que a Floresta Ombrófila Densa foi raramente registrada. As Florestas Aluviais (várzea) foram encontradas ao longo de uma estreita faixa de terra ao longo das margens do rio Madeira, nos solos mais férteis da área de estudo. As Florestas Semidecíduas foram encontradas em pequenas áreas de afloramentos rochosos com solos pouco profundos e disponibilidade de água reduzida durante a estação seca. As Campinaranas, que variam de fisionomias de savana aberta a floresta de dossel fechado, constituem-se em um ambiente chave nas terras baixas ao sul do rio Madeira, em solos siltosos, hidromórficos, e abrigam uma flora peculiar, tolerante às inundações durante a estação chuvosa. Nossa classificação dos principais tipos de vegetação no alto rio Madeira revela um alto grau de heterogeneidade florística e ambiental em uma região altamente ameaçada. Nossos resultados serão úteis para a elaboação de estratégias de conservação destinadas a proteger toda a gama de diversidade florística presente na região.

Vascular Flora of the Tocantins River Middle Basin, Brazil

This study provides a checklist of the phanerogams and pteridophytes of the Tocantins river middle basin, in northern Goias state and southern Tocantins state, Brazil. Herbarium samples were collected from 2000 to 2009 and this floristic survey recorded 1572 species from 135 families. The most species-rich families were Fabaceae (217), Poaceae (116), Asteraceae (88), Euphorbiaceae (65), Orchidaceae (58) and Malpighiaceae (56). Furthermore, 14 endangered species and 31 rare species were recorded, mainly associated with the campos rupestres in the Veadeiros Plateau region. The flora mainly from the phytophyisiognomies cerrado stricto sensu , campo rupestre (“rocky fields”), mata de galeria (“gallery forest”), mata ciliar (“riverine forest”) and semi-deciduous seasonal forest comprised typical species of the mid-western Cerrado floristic province, such as the most widely known woody plants Anadenanthera colubrina (Vell.) Brenan (popular name angico ), Aspidosperma subincanum Mart. ex A. DC. ( guatambu ), Astronium fraxinifolium Schott ex Spreng. ( goncalo-alves ), Callisthene fasciculata Mart. ( pau-jacare ), Dipteryx alata Vogel ( baru ), Guazuma ulmifolia Lam. ( mutamba ) and Magonia pubescens A. St.-Hil. ( tingui ). This study is the first to record a wide floristic list of this important region of central Brazil.

Incêndios florestais no entorno de Unidades de Conservação – estudo de caso na Estação Ecológica de Águas Emendadas, Distrito Federal.

This study aimed to analyze aspects of fire use on urban areas around Aguas Emendadas Ecological Station (ESECAE), in Distrito Federal, and to evaluate the foremost fire occurrences, equipment availability and tools for combatants and beyond decreasing forest fire incidences. The local population in town region around it (considering three kilometers as ray from the station), fire crew members units of conservation and the garrison body of firemen were interviewed in a representative form. Results had shown that most inclined areas to forest fire occurrence (33.4% highways edges and secondary roads) had their localization related to urban environment, in which 34% of residents used fire as land cleanness. Machines availability, tools and equipment for execution of the activities on prevention and combat exist; however, there is not any equipment for individual protection for all fire crew members. As a solution, educative campaigns to emphasize the negative consequences of using fire (as a tool land) and also to alert people for the risks caused by it should be done.

Species distribution models of rare tree species as an evaluation tool for synergistic human impacts in the Amazon rainforest

Abstract In the present work, we have considered the vulnerability of some rare tree species to human disturbances in a high biodiversity tropical region. In this context, we aimed to evaluate the combined effect of deforestation and artificial flooding of the large Jirau hydroelectric reservoir on potential distribution areas of 13 locally rare tree species in the southwestern Brazilian Amazon. We performed species distribution modeling (SDM) by using the environmental distance algorithm. Based on these models, we found new sites and subsequently applied rapid ecological assessment to collect further species occurrence data. Additional SDMs were carried out using MaxEnt to determine the potential distribution areas of these rare species. We found that artificial flooding and deforestation caused combined losses of potential distribution areas of rare tree species between 8 and 39% of the total area. The most vulnerable species were Semaphyllanthe megistocaula (K. Krause) L. Andersson (Rubiaceae) (39%), Chrysophyllum colombianum (Aubrév.) T.D. Penn. (Sapotaceae) (34%), Lacunaria jenmanii (Oliv.) Ducke (Quiinaceae) (32%), Brosimum parinarioides Ducke (Moraceae) (32%) and Xylopia benthamii R.E. Fr. (Annonaceae) (30%). These results indicate an additive effect of human disturbances such that artificial flooding, when combined with deforestation, has an overall effect by orders of magnitude. SDMs can be effectively used as a predictive tool in the assessment of human impacts on rare tree species in tropical forests. The results also showed different vulnerability among the rare species, and these results may indicate that some species are more seriously threatened by the extreme loss of potential distribution areas.

Regeneração e estrutura populacional de jatobá-da-mata (Hymenaea courbaril L.), em dois fragmentos com diferentes graus de perturbação antrópica

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 population 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.

The role of recruitment and dispersal limitation in tree community assembly in Amazonian forests

ABSTRACT Background: Species composition of plant communities is shaped by the interplay between dispersal limitation, environmental filters and stochastic events. Aims: The aim of this work was to investigate the effects of dispersal limitation and environmental filtering on tree recruitment. To accomplish this, we employed the unified neutral theory of biodiversity and biogeography to examine migration within the metacommunity, defined as a set of interacting local communities linked by the dispersal of multiple potentially interacting species. Methods: We sampled 12,975 individuals with dbh ≥ 1 cm in 26 1-ha permanent plots, including habitats of terra firme, transitional forests, várzea and campinarana, on the upper Madeira River, Brazilian Amazon. Results: Campinarana drew individuals from outside the metacommunity species pool at a mean probability of recruitment of 0.06, a much lower probability than terra firme (0.31), transitional (0.21) and várzea forests (0.22). Environmental variables, such as water table depth, soil texture and fertility, were related to differences in community assembly. Conclusions: Species abundance distribution and diversity patterns of plant assemblages in a large river landscape in the Amazon highlight the importance of environmental heterogeneity that conditions beta-diversity. The high variation in recruitment probabilities from the metacommunity species pool to local communities suggests high habitat variability in the process of maintaining patterns of local diversity.

Floristic and structural comparisons between woody communities of two seasonal forest fragments in the Tocantins river basin and other remnants of this forest physiognomy in Brazil

This work describes the woody layer composition and structure in two seasonal forest fragments in the Tocantins river basin and compares them to other remnants of this forest physiognomy in Brazil. The survey was carried out by using 17 plot samples (20 × 50 m) located in Palmeiropolis, state of Tocantins, and in Minacu, state of Goias. All woody individuals showing diameters > 5 cm, at 1.30 cm above ground level, were recorded. The higher floristic similarity of these forest remnants compared with other closer seasonal forests did not show a distinct pattern. The floristic composition was more similar to that of a deciduous seasonal forest in the Parana valley, and more dissimilar to other forests in this same valley. This result and a higher dissimilarity related to the southern forests in Goias suggest that the forest fragments showed a floristic composition and structure typical of lowland seasonal forests in the Tocantins river basin. The results also indicated that the forest fragments have distinct floristic compositions with a relatively similar structure and diversity.