Canopy gap colonization in the Atlantic Montane Rain Forest

Na Floresta Pluvial Atlântica Montana do Sudeste Brasileiro, foi realizado um estudo para descrever e avaliar a colonização de clareiras. A composição de clareiras foi levantada através da cobertura do solo para as espécies herbáceas enquanto que todos os indivíduos lenhosos maiores que um metro de altura foram mensurados e identificados. Também foram coletadas informações sobre a estrutura das clareiras (área da clareira, número e diâmetro das quedas), posição topográfica e vegetação circundante. Dois gêneros de Marantaceae apresentaram considerável freqüência e abundância nas clareiras. As espécies lenhosas mais freqüentes e abundantes pertenceram ao grupo não-pioneiro e as famílias mais ricas encontradas nas clareiras não diferiram quando comparado à floresta como um todo. Como para as variáveis do estrato herbáceo e da vegetação circundante, os resultados revelaram que efeitos diretos e indiretos da topografia são importantes na determinação da composição interna de clareiras por espécies lenhosas. Estes resultados sugerem que a colonização de clareiras é influenciada não apenas pelas variáveis de estrutura, mas também pela posição topográfica e pelos indivíduos pré-estabelecidos.

Associations between fish assemblage and riparian vegetation in the Corumbataí River Basin (SP)

Este trabalho teve o objetivo de examinar se existem associações entre as espécies de peixes e o estado de conservação das matas ciliares na bacia do rio Corumbataí. Foram escolhidos 4 rios principais com 3 pontos de coleta em cada um. Foram realizadas coletas nos períodos de março a junho e de setembro a dezembro de 2001. Técnicas multivariadas foram aplicadas para determinar a correlação entre a riqueza de espécies e a ordem dos rios, estado de preservação da mata ciliar, sombreamento, presença ou ausência de Eucalyptus, cana-de-açúcar e pastagens, e nível de estabilidade do barranco ao redor dos pontos de coleta. A riqueza de espécies foi maior em locais com maior cobertura vegetal e mata ciliar preservada.

Meso and microhabitat analysis and feeding habits of small nektonic characins (Teleostei: Characiformes) in Neotropical streams

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Assessment of tropical forest degradation by selective logging and fire using Landsat imagery

Many studies have assessed the process of forest degradation in the Brazilian Amazon using remote sensing approaches to estimate the extent and impact by selective logging and forest fires on tropical rain forest. However, only a few have estimated the combined impacts of those anthropogenic activities. We conducted a detailed analysis of selective logging and forest fire impacts on natural forests in the southern Brazilian Amazon state of Mato Grosso, one of the key logging centers in the country. To achieve this goal a 13-year series of annual Landsat images (1992-2004) was used to test different remote sensing techniques for measuring the extent of selective logging and forest fires, and to estimate their impact and interaction with other land use types occurring in the study region. Forest canopy regeneration following these disturbances was also assessed. Field measurements and visual observations were conducted to validate remote sensing techniques. Our results indicated that the Modified Soil Adjusted Vegetation Index aerosol free (MSAVI(af)) is a reliable estimator of fractional coverage under both clear sky and under smoky conditions in this study region. During the period of analysis, selective logging was responsible for disturbing the largest proportion (31%) of natural forest in the study area, immediately followed by deforestation (29%). Altogether, forest disturbances by selective logging and forest fires affected approximately 40% of the study site area. Once disturbed by selective logging activities, forests became more susceptible to fire in the study site. However, our results showed that fires may also occur in undisturbed forests. This indicates that there are further factors that may increase forest fire susceptibility in the study area. Those factors need to be better understood. Although selective logging affected the largest amount of natural forest in the study period, 35% and 28% of the observed losses of forest canopy cover were due to forest fire and selective logging combined and to forest fire only, respectively. Moreover, forest areas degraded by selective logging and forest fire is an addition to outright deforestation estimates and has yet to be accounted for by land use and land cover change assessments in tropical regions. Assuming that this observed trend of land use and land cover conversion continues, we predict that there will be no undisturbed forests remaining by 2011 in this study site. Finally, we estimated that 70% of the total forest area disturbed by logging and fire had sufficiently recovered to become undetectable using satellite data in 2004. (C) 2010 Elsevier B.V. All rights reserved.

Carbon Stocks and Isotopic Composition of the Organic Matter in Soils Covered by Native Vegetation and Pasture in Sorocaba, SP, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The reproductive biology of Cybistax antisyphilitica (Bignoniaceae), a characteristic tree of the South American savannah-like "Cerrado" vegetation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Roadside vegetation: estimation and potential for carbon sequestration

The present paper reports the assessment of the vegetation occupancy rate of the roadside, through analysis of aerial photographs. Using such value the potential of these areas to be employed as carbon (C) sinks was also assessed. Moreover, for the areas suitable for afforestation, the potential for carbon sequestration was estimated considering different species of vegetation, both native (scenario 1) and exotic (formed by Pinus sp. and Eucalyptus sp. - scenario 2). The study was carried out through GIS techniques and two regions were considered. A set of equations was used to estimate the rate of occupancy over the study areas, as well as amounts of fixed C under the above scenarios. The average occupancy rate was 0.06%. The simulation showed a higher potential for C sequestration in scenario 2, being the estimated amounts of CO(2) sequestered from the atmosphere per km of roadside: 131 tons of CO(2) km(-1) of highway to native species and 655 tons of CO(2) km(-1) of highway for exotic species (over period of 10 years for both estimates). If we consider the whole road network of the São Paulo State (approximately 190 000 km) and that a considerable part of this road work is suitable to receive this kind of service, it is possible to predict the very high potential for C sequestration if managers and planners consider roadside as area for afforestation.

Distribution of extrafloral nectaries in different vegetation types of Amazonian Brazil

Surveys were carried out in terra firme' forest, successional forest, buritirana' (palm vegetation) and shrub canga' (savanna). Extrafloral nectaries (EFNs) were present in 30 plant species belonging to 22 genera and 14 families. Nectary species represented 17.6-53.3% of the species samples in different areas, with local abundances varying from 19.1-50.0%. The percentage of species with EFNs was greater in the flora of the shrub canga than in the terra firme and successional forests. Nectary plants were more abundant in the shrub canga and successional forest. The high abundance of EFNs may be the result of intense foraging activity by ants on plants, leading to the formation of facultative mutualism. -from Authors

Cumulative effects of vinasse on the characteristics of red-yellow latosols under cerrado vegetation

Vinasse, a liquor effluent from the alcohol and sugar making industry, was applied annually for twelve years to medium-textured red-yellow latosols under cerrado vegetation sensu stricto, to study the environmental impacts on the biotic and abiotic factors. Four plots were established of which two acted as control and the other two received annual doses of vinasse. The studies were begun in 1980 when the first annual dose of 20 L m-2 year-1 was added to the soil without removing the top scrub layer. Theses doses were added to the soil until 1983, but in 1984 the doses were increased to 50 L m-2 year-1 and used until 1991. Soil samples were taken at a depth of 15 cm every three months from 1987 to 1991. Twenty seven environmental variables in the vinasse-treated and untreated plots were studied. These factors consisted of different enzymatic activities, a number of filamentous fungi, bacteria, actinomycetes and other micro-organisms, nutrients and some micro-climatic factors. The results obtained were statistically analyzed using the Tukey test, Pearson correlation and variance test methods with replicates and three factors. Matrices were determined using the correlation coefficient method and were compared with those of earlier published studies in the same area. The comparison of the results helped characterize changes in the environmental factors studied and in the correlation between them, after using annual cumulative doses of vinasse. Positive effects were observed only for the first six years of this application but vinasse had negative effects after the seventh year. It is concluded that medium-textured red-yellow latosols cannot be treated with vinasse for proloned periods.

Ecological interaction between Atta sexdens (Hymenoptera: Formicidae) and the vegetation of a mesophyll semideciduous forest fragment in Botucatu, SP, Brazil

Among 89 plants species growing in a subtropical dry forest fragment located in Botucatu, State of São Paulo, Brazil, 35 species were cut by Atta sexdens, representing 39.34% of the current plants existing in this area. A. sexdens L., 1758 (Hymenoptera: Formicidae) has a selective preference for the following species: Alchornea triplinervia, Faramea cyanea, Cariniana estrellensis and Casearea obliqua, with the first being the most cut species. The frequency and absolute densities of the plant families and species significantly influence the selection process. When comparing the absolute frequency regarding the 10 most cut plant species and the cutting frequency, significant data were obtained only for the euphorbiaceous A. triplinervia species, proving the preference of A. sexdens for this species in particular. These interactions are discussed based on ecological and management factors in agro-ecosystems.

Including the sub-grid scale plume rise of vegetation fires in low resolution atmospheric transport models

We describe and begin to evaluate a parameterization to include the vertical transport of hot gases and particles emitted from biomass burning in low resolution atmospheric-chemistry transport models. This sub-grid transport mechanism is simulated by embedding a 1-D cloud-resolving model with appropriate lower boundary conditions in each column of the 3-D host model. Through assimilation of remote sensing fire products, we recognize which columns have fires. Using a land use dataset appropriate fire properties are selected. The host model provides the environmental conditions, allowing the plume rise to be simulated explicitly. The derived height of the plume is then used in the source emission field of the host model to determine the effective injection height, releasing the material emitted during the flaming phase at this height. Model results are compared with CO aircraft profiles from an Amazon basin field campaign and with satellite data, showing the huge impact that this mechanism has on model performance. We also show the relative role of each main vertical transport mechanisms, shallow and deep moist convection and the pyro-convection (dry or moist) induced by vegetation fires, on the distribution of biomass burning CO emissions in the troposphere.

The Latin American experience in pension system reform: coverage, fiscal issues and possible implications for China

Includes bibliography

Taxa de semeadura de Brachiaria brizantha consorciada com milho na incidência de plantas daninhas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise temporal do uso do solo e comparação entre os índices de vegetação ndvi e savi no município de Santa Cruz do Rio Pardo - SP usando imagens landsat-5

This work aims to analyze the land use evolution in the city of Santa Cruz do Rio Pardo - SP through supervised classification of Landsat-5 TM satellite images according to the maximum likelihood (Maxlike), as well as verifying the mapping accuracy through Kappa index, comparing NDVI and SAVI vegetation indexes in different adjustment factors for the canopy substrate and determining the vegetal coverage percentage in all methods used on 2007, May 26 th; 2009, January 7 th and 2009, April 29 th. The Maxlike classification showed several spatial changes in land use over the study period. The most appropriated vegetation indexes were NDVI and SAVI - 0,25 factor, which showed similar values of vegetal coverage percentage, but discrepant from the inferred value for Maxlike classification.

Combination of orthodontic movement and periodontal therapy for full root coverage in a miller class iii recession: A case report with 12 years of follow-up

One of the main purposes of mucogingival therapy is to obtain full root coverage. Several treatment modalities have been developed, but few techniques can provide complete root coverage in a class III Miller recession. Thus, the aim of this case report is to present a successful clinical case of a Miller class III gingival recession in which complete root coverage was obtained by means of a multidisciplinary approach. A 17-year-old Caucasian female was referred for treatment of a gingival recession on the mandibular left central incisor. The following procedures were planned for root coverage in this case: free gingival graft, orthodontic movement by means of alignment and leveling and coronally advanced flap (CAF). The case has been followed up for 12 years and the patient presents no recession, no abnormal probing depth and no bleeding on probing, with a wide attached gingiva band. A compromised tooth with poor prognosis, which would be indicated for extraction, can be treated by orthodontic movement and periodontal therapy, with possibility of 100% root coverage in some class III recessions.