Economic and social impacts of logging at national forests - a study case at Brazil

Brazil has the largest tropical rainforests in the world and most of them are located at Amazon River basin area. During the last three decades, deforestation are growing very fast in this region, having negative impacts at local and global weather. In order to minimize these impacts and protect part of the biodiversity, Brazilian government established several national forests in this area, but just one have being explored, the Tapajós National Forest (known as Flona Tapajós). This paper evaluates the economic and social features of a reduced impact logging project conducted at Flona Tapajós from 1999 to 2003. It was coordinated by IBAMA (the Brazilian governmental agency responsible for managing National Forests), funded by ITTO (International Tropical Timber Organization) and conducted by Treviso Agropecuária Ltda (a private enterprise). This project is locally known as ITTO project. Basing on field interviews and examining IBAMA´s and Treviso´s documents, this paper concludes that ITTO project was highly profitable for the private company, in spite of the company had obeyed all Brazilian working laws, what is not very common at this Brazilian region. Treviso´s internal rate of return was 35.79%. ITTO project impacted significantly the community workers involved with the project and it was able to teach this population how to manage rainforests in order to produce timber without destroying them. The paper ends by suggesting some attitudes that Brazilian government can follow in its discussion about new reduced impact logging projects to be implemented at Flona Tapajós and other national forests by both private enterprises and local communities.

Forest disturbance and growth processes are reflected in the geographical distribution of large canopy gaps across the Brazilian Amazon

Canopy gaps are openings in the forest canopy resulting from branch fall and tree mortality events. The geographical distribution of large canopy gaps may reflect underlying variation in mortality and growth processes. However, a lack of data at the appropriate scale has limited our ability to study this relationship until now. We detected canopy gaps using a unique LiDAR dataset consisting of 650 transects randomly distributed across 2500 km(2) of the Brazilian Amazon. We characterized the size distribution of canopy gaps using a power law and we explore the variation in the exponent, alpha. We evaluated how the alpha varies across the Amazon, in response to disturbance by humans and natural environmental processes that influence tree mortality rates. We observed that South-eastern forests contained a higher proportion of large gaps than North-western, which is consistent with recent work showing greater tree mortality rates in the Southeast than the Northwest. Regions characterized by strong wind gust speeds, frequent lightning and greater water shortage also had a high proportion of large gaps, indicating that geographical variation in alpha is a reflection of underlying disturbance processes. Forests on fertile soils were also found to contain a high proportion of large gaps, in part because trees grow tall on these sites and create large gaps when they fall; thus, canopy gap analysis picked up differences in growth as well as mortality processes. Finally, we found that human-modified forests had a higher proportion of large gaps than intact forests, as we would expect given that these forests have been disturbed. Synthesis. The proportion of large gaps in the forest canopy varied substantially over the Brazilian Amazon. We have shown that the trends can be explained by geographical variation in disturbance and growth. The frequency of extreme weather events is predicted to increase under climate change, and changes could lead to greater forest disturbance, which should be detectable as an increased proportion of large gaps in intact forests.Peer reviewe

Protective Effect of Prolactin against Methylmercury-Induced Mutagenicity and Cytotoxicity on Human Lymphocytes

Mercury exhibits cytotoxic and mutagenic properties as a result of its effect on tubulin. This toxicity mechanism is related to the production of free radicals that can cause DNA damage. Methylmercury (MeHg) is one of the most toxic of the mercury compounds. It accumulates in the aquatic food chain, eventually reaching the human diet. Several studies have demonstrated that prolactin (PRL) may be differently affected by inorganic and organic mercury based on interference with various neurotransmitters involved in the regulation of PRL secretion. This study evaluated the cytoprotective effect of PRL on human lymphocytes exposed to MeHg in vitro, including observation of the kinetics of HL-60 cells (an acute myeloid leukemia lineage) treated with MeHg and PRL at different concentrations, with both treatments with the individual compounds and combined treatments. All treatments with MeHg produced a significant increase in the frequency of chromatid gaps, however, no significant difference was observed in the chromosomal breaks with any treatment. A dose-dependent increase in the mitotic index was observed for treatments with PRL, which also acts as a co-mitogenic factor, regulating proliferation by modulating the expression of genes that are essential for cell cycle progression and cytoskeleton organization. These properties contribute to the protective action of PRL against the cytotoxic and mutagenic effects of MeHg.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)IFPA Itaituba, Fed Inst Educ Sci & Technol Para, BR-68180000 Campinas, Para, BrazilFed Univ Para, Inst Biol Sci, BR-66075110 Belem, Para, BrazilIFPA, Educ Fed Inst Sci & Technol Para, BR-66645240 Belem, Para, BrazilUniv Para, Ctr Biol & Hlth Sci, BR-66050540 Belem, Para, BrazilFed Univ Western Para, UFOPA, BR-68040470 Santarem, Para, BrazilUniversidade Federal de São Paulo, Dept Morphol & Genet, BR-04021001 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Morphol & Genet, BR-04021001 São Paulo, BrazilWeb of Scienc

Comprehensive study of reaction mechanisms for the Be9+Sm144 system at near- and sub-barrier energies

The delayed x-ray detection technique was used to measure complete and incomplete fusion cross sections for the $^{9}\mathrm{Be}+^{144}\mathrm{Sm}$ reaction at sub- and near-barrier energies. Elastic and inelastic scattering for this system were also measured. Reaction cross sections were derived and the transfer cross sections of one neutron were calculated. The suppression of complete fusion above the barrier, of the order of 10%, is attributed to $^{9}\mathrm{Be}$ breakup and is considerably smaller than the value of 30% found for the $^{9}\mathrm{Be}+^{208}\mathrm{Pb}$ system

Construct validity of a figure rating scale for Brazilian adolescents

<p>Abstract</p> <p>Background</p> <p>Figure rating scales were developed as a tool to determine body dissatisfaction in women, men, and children. However, it lacks in the literature the validation of the scale for body silhouettes previously adapted. We aimed to obtain evidence for construct validity of a figure rating scale for Brazilian adolescents.</p> <p>Methods</p> <p>The study was carried out with adolescent students attending three public schools in an urban region of the municipality of Florianopolis in the State of Santa Catarina (SC). The sample comprised 232 10-19-year-old students, 106 of whom are boys and 126 girls, from the 5th "series" (i.e. year) of Primary School to the 3rd year of Secondary School. Data-gathering involved the application of an instrument containing 8 body figure drawings representing a range of children's and adolescents' body shapes, ranging from very slim (contour 1) to obese (contour 8). Weights and heights were also collected, and body mass index (BMI) was calculated later. BMI was analyzed as a continuous variable, using z-scores, and as a dichotomous categorical variable, representing a diagnosis of nutritional status (normal and overweight including obesity).</p> <p>Results</p> <p>Results showed that both males and females with larger BMI z-scores chose larger body contours. Girls with higher BMI z-scores also show higher values of body image dissatisfaction.</p> <p>Conclusion</p> <p>We provided the first evidence of validity for a figure rating scale for Brazilian adolescents.</p

Hyperdominance in Amazonian Forest Carbon Cycling

While Amazonian forests are extraordinarily diverse, the abundance of trees is skewed strongly towards relatively few ‘hyperdominant’ species. In addition to their diversity, Amazonian trees are a key component of the global carbon cycle, assimilating and storing more carbon than any other ecosystem on Earth. Here we ask, using a unique data set of 530 forest plots, if the functions of storing and producing woody carbon are concentrated in a small number of tree species, whether the most abundant species also dominate carbon cycling, and whether dominant species are characterized by specific functional traits. We find that dominance of forest function is even more concentrated in a few species than is dominance of tree abundance, with only ≈1% of Amazon tree species responsible for 50% of carbon storage and productivity. Although those species that contribute most to biomass and productivity are often abundant, species maximum size is also influential, while the identity and ranking of dominant species varies by function and by region

The global abundance of tree palms

Aim Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location Tropical and subtropical moist forests. Time period Current. Major taxa studied Palms (Arecaceae). Methods We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co‐occurring non‐palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in >80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long‐term climate stability. Life‐form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non‐tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above‐ground biomass, but the magnitude and direction of the effect require additional work. Conclusions Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests