Modelagem estatística e atribuições dos eventos de precipitação extrema na Amazônia brasileira

Intense precipitation events (IPE) have been causing great social and economic losses in the affected regions. In the Amazon, these events can have serious impacts, primarily for populations living on the margins of its countless rivers, because when water levels are elevated, floods and/or inundations are generally observed. Thus, the main objective of this research is to study IPE, through Extreme Value Theory (EVT), to estimate return periods of these events and identify regions of the Brazilian Amazon where IPE have the largest values. The study was performed using daily rainfall data of the hydrometeorological network managed by the National Water Agency (Agência Nacional de Água) and the Meteorological Data Bank for Education and Research (Banco de Dados Meteorológicos para Ensino e Pesquisa) of the National Institute of Meteorology (Instituto Nacional de Meteorologia), covering the period 1983-2012. First, homogeneous rainfall regions were determined through cluster analysis, using the hierarchical agglomerative Ward method. Then synthetic series to represent the homogeneous regions were created. Next EVT, was applied in these series, through Generalized Extreme Value (GEV) and the Generalized Pareto Distribution (GPD). The goodness of fit of these distributions were evaluated by the application of the Kolmogorov-Smirnov test, which compares the cumulated empirical distributions with the theoretical ones. Finally, the composition technique was used to characterize the prevailing atmospheric patterns for the occurrence of IPE. The results suggest that the Brazilian Amazon has six pluvial homogeneous regions. It is expected more severe IPE to occur in the south and in the Amazon coast. More intense rainfall events are expected during the rainy or transitions seasons of each sub-region, with total daily precipitation of 146.1, 143.1 and 109.4 mm (GEV) and 201.6, 209.5 and 152.4 mm (GPD), at least once year, in the south, in the coast and in the northwest of the Brazilian Amazon, respectively. For the south Amazonia, the composition analysis revealed that IPE are associated with the configuration and formation of the South Atlantic Convergence Zone. Along the coast, intense precipitation events are associated with mesoscale systems, such Squall Lines. In Northwest Amazonia IPE are apparently associated with the Intertropical Convergence Zone and/or local convection.

Colônia agrícola Sinimbú: entre a regularidade do espaço projetado e os violentos confrontos do espaço vivido (Rio Grande do Norte, 1850-1880)

In 1878, at the province of Rio Grande do Norte, between Ceará-Mirim and Extremoz, was founded the Agricultural Colony of Sinimbú. On this location, about 6,600 freed men and women had gathered. They were not only fleeing from the terrible 1877 drought but also encouraged by the promise of accessing basic necessities, i.e. housing and medical assistance, upon work, as required by local and central representatives of power. However, the migrants faced otherwise reality, since conditions within the agricultural facility were of shortage and violence, as denounced on the presidential reports of that time. This work aims at analyzing the conflicts that took place at the Sinimbú Colony, while it seeks to emphasize how the tensions and interests of both local elite and central government representatives relate to the opening and closure of this space, on a context where the debate on the control over freed poor workers was on the rise. Thus, we intend to demonstrate that on the one hand, institutionalized places provided the native freed a sense of work guided by the discipline of the body, control of time and arrangement of space. On the other hand, unlike forms of resistance enacted by freed working men and women undergoing the rearranging process of labor world cannot be disregarded.

Análise da variabilidade climática sobre a produtividade da soja no município de Bom Jesus (PI)

The climate is still main responsible for the variations soybean productivity (Glycine max (L.) Merrill), exerting a limiting action on these agricultural systems. The bomjesuense cerrado, this culture has proved, over the years, an increase of cultivated areas, however, productivity does not keep the same pace, going through periods of oscillations. Thus, although the crop is added to high technology, culture has great vulnerability to climatic adversities. Thus, the present study aims to analyze possible trends in meteorological variables, which can influence the soybean yield in Bom Jesus. For this purpose, different datasets were used, as follows: i) two periods of daily data (1984-2014 and 1974-2014), both obtained from the National Meteorological Institute (INMET); ii) climate normals from 1961-1990 as defined by INMET; iii) local agricultural production data of soybean-year (1997/1998 to 2012/2013) obtained from the Municipal Agricultural Production (PAM) dataset, which is management by Brazilian Institute of Geography and Statistics (IBGE). The analysis procedures included calculations of climate normals for 1984 to 2014 period and some statistical applications, as follows: i) the Wilcoxon test, used to evaluate differences between climate normals (1961 to 1990 and 1984 to 2014); ii) the Mann-Kendall nonparametric test, in order to analyze the linear trend of agrometeorological variables (rainfall, maximum temperature, minimum temperature and diurnal range of temperature; iii) cluster analysis by Ward method and the Spearman correlation test (rs) to identify the relationship between agrometeorological variable and soybean annual productivity. We adopted a statistical significance level of 5%. The results indicate changes in seasonality of the 1984-2014 climatology with respect to past climatology for all variables analyzed, except for insolation and precipitation. However, the monthly analysis of precipitation indicate negative trend during October and positive trend in December, causing a delay in start of rainy season. If this trend is persistent this result must be considered in futures definitions of the soybean crop sowing date over the region studied. With Mann-Kendall test was possible to identify positive trends with statistical significance in maximum temperature for all month forming part of soybean cycle (from November to April), which in turn tends to cause adverse effects on crop physiology, and consequently impacts on the final yield. Was identified a significant positive correlation between soybean yield and precipitation observed in March, thus precipitation deficit in this month is harmful to the soybean crop development. No statistically significant correlation was identified among maximum temperature, minimum temperature, and DTR with annual soybean productivity due these range of meteorological variables are not limiting factors in the final soybean yield in Bom Jesus (PI). It is expected that this study will contribute to propose planning strategies considering the role of climate variability on soybean crop final yield.

Efeito do trabalho de projeto na abordagem da estatística nas atitudes face à matemática de alunos do 6.º ano de escolaridade

O presente trabalho constitui uma investigação levada a cabo no âmbito do Mestrado e Ensino do 1.º e 2.º Ciclos de Educação Básica. A problemática surgiu no decorrer da minha prática pedagógica no seio de uma turma do 6.º ano, numa Escola Básica do centro do país. Partindo da necessidade da tomada de posição perante o ensino e a sua finalidade, centra-se na perspetiva de que além da promoção de aquisição de informação, conteúdo e experiência Matemática, também é finalidade do ensino desta disciplina o desenvolvimento de atitudes positivas face à mesma e a capacidade de apreciar esta ciência. Pretende verificar o efeito de um trabalho de projeto nas atitudes dos alunos, pois conhecer apenas a atitude que apresentam em relação à matemática não previne que a mesma evolua no sentido negativo ao longo da escolaridade obrigatória. O projeto realizado na turma teve como dinâmica o trabalho de grupo, no qual os alunos desempenharam o papel de produtores e de consumidores de informação estatística. Avalia a atitude dos alunos em três momentos da concretização do projeto – antes, durante e depois; por forma a evidenciar semelhanças e diferenças nos três momentos, bem como o que poderá ter influenciado o resultado obtido. Considerando a atitude com base em três componentes principais – afetiva, cognitiva e comportamental, a análise dos dados traduziu-se na análise das expressões de comportamento verbal e não-verbal a partir da qual foi inferida a componente de atitude refletida. Os resultados obtidos apontam para uma melhoria nas atitudes dos alunos mediante a metodologia utilizada, nomeadamente no que respeita à apreciação desta ciência através da compreensão da sua aplicabilidade no quotidiano diário e futuro profissional, bem como ao autoconhecimento das suas competências em relação ao tema matemático abordado. Poderia ter tido uma influência mais positiva nas atitudes dos alunos, nomeadamente na componente comportamental, se estes já tivessem desenvolvido competências intrínsecas ao trabalho cooperativo.

Sostenibilidad de modos ancestrales de producción agrícola en el Perú : ¿conservar o sustituir?

Frente al éxito de algunos productos andinos como la quinua, la papa o la maca en el comercio agroalimentario internacional y ante la creciente degradación ambiental que afrontan los países en desarrollo producto de actividades de explotación intensiva; nuestra investigación busca evidenciar la tendencia que se asume desde la comunidad académica/científica y los funcionarios públicos del sector agroalimentario en el Perú, frente a la necesidad de mantener sostenible diversos modos ancestrales de producción agrícola (caso quinua), para ello analizamos información cuantitativa y cualitativa obtenida de las instituciones públicas y las universidades peruanas.

Sostenibilidad de modos ancestrales de producción agrícola en el Perú : ¿conservar o sustituir?

Frente al éxito de algunos productos andinos como la quinua, la papa o la maca en el comercio agroalimentario internacional y ante la creciente degradación ambiental que afrontan los países en desarrollo producto de actividades de explotación intensiva; nuestra investigación busca evidenciar la tendencia que se asume desde la comunidad académica/científica y los funcionarios públicos del sector agroalimentario en el Perú, frente a la necesidad de mantener sostenible diversos modos ancestrales de producción agrícola (caso quinua), para ello analizamos información cuantitativa y cualitativa obtenida de las instituciones públicas y las universidades peruanas.

Sostenibilidad de modos ancestrales de producción agrícola en el Perú : ¿conservar o sustituir?

Frente al éxito de algunos productos andinos como la quinua, la papa o la maca en el comercio agroalimentario internacional y ante la creciente degradación ambiental que afrontan los países en desarrollo producto de actividades de explotación intensiva; nuestra investigación busca evidenciar la tendencia que se asume desde la comunidad académica/científica y los funcionarios públicos del sector agroalimentario en el Perú, frente a la necesidad de mantener sostenible diversos modos ancestrales de producción agrícola (caso quinua), para ello analizamos información cuantitativa y cualitativa obtenida de las instituciones públicas y las universidades peruanas.