Vulnerabilidade à erosão hídrica do solo, bacia hidrográfica do rio Araguaia

O entendimento dos efeitos climáticos e do uso do solo em conjunto é crucial para análise ambiental e prevenções de desastres naturais. O objetivo deste trabalho é analisar a vulnerabilidade à erosão hídrica do solo na bacia hidrográfica do rio Araguaia. Usou-se dados de precipitação (Agência Nacional das Águas); uso e ocupação da terra (Projeto MapBiomas); declividade (Instituto Nacional de Pesquisas Espaciais) e de solo (Empresa Brasileira de Pesquisas Agropecuária) no cálculo de mapas através do geoprocessamento para obter-se a representação da erosão hídrica do solo. A bacia hidrográfica do rio Araguaia caracteriza-se na maior parte por zonas de transição de estabilidade e vulnerabilidade, porém destaca-se as áreas estáveis nas proximidades da foz, regiões críticas á sudoeste (Rio das Mortes), nos limites (leste) do Alto Araguaia, nas partes sudeste e sudoeste do Baixo Araguaia. Na escala climática, a precipitação não apresenta riscos significativos. No entanto, o intenso uso e ocupação da terra na região foi a forçante que maior agravou a vulnerabilidade, principalmente em áreas (declives e solo) naturalmente instáveis. Assim, algumas cidades precisam estar em alerta para possíveis eventos erosivos. Vulnerability to soil water erosion, Araguaia basin riverA B S T R A C TThe Understanding climate effects and land use together is crucial for environmental analysis and natural disaster prevention. The objective of this work is to analyze the vulnerability to soil water erosion in the hydrographic basin of the Araguaia river. Rainfall data (National Water Agency) was used; land use and occupation (MapBiomas Project); slope (National Institute for Space Research) and soil (Brazilian Agricultural Research Corporation) in the calculation of maps through geoprocessing to obtain the representation of soil water erosion. The hydrographic basin of the Araguaia river is characterized in the most part by transition zones of stability and vulnerability, however the stable areas in the vicinity of the mouth stand out, critical regions to the southwest (Rio das Mortes), on the (eastern) limits of the Alto Araguaia, in the southeast and southwest parts of the Lower Araguaia. On the climate scale, the rainfall does not present significant risks. However, the intense use and occupation of land in the region was the forcing that increased the risk, mainly in naturally unstable areas (slopes and soil). Thus, some cities need to be alert to possible erosive events.

MODELADO DEL COMPORTAMIENTO A FLEXIÓN DE SECCIONES DE HORMIGÓN CON FIBRAS MEDIANTE LA HIPÓTESIS DE FISURA PLANA

Este trabajo presenta un modelo para evaluar el comportamiento a flexión de secciones de hormigón reforzado con fibras (FRC). El comportamiento a tracción del hormigón con fibras se representa mediante un modelo cohesivo a través de la ley de ablandamiento lineal incluida en el Código Modelo-2010. Como ecuación de compatibilidad se hace uso de la hipótesis de fisura plana, es decir, se asume que las caras de la fisura permanecen planas durante todo el proceso de fractura, hipótesis que ha sido contrastada recientemente mediante correlación digital de imágenes [1]. El comportamiento a compresión del hormigón se representa a través de un modelo elástico, usando la hipótesis de Navier. La apertura de fisura se evalúa a partir del momento aplicado en la sección y de la profundidad de la fisura a través de la expresión propuesta por Tada et al. [2]. El modelo reproduce el efecto de escala existente en la resistencia a flexotracción (módulo de ruptura) en hormigón y hormigón con fibras. Asimismo se define un número de fragilidad que permite caracterizar el comportamiento de las secciones tanto de hormigón en masa como FRC. La metodología presentada propone el análisis de secciones de FRC a través de diagramas que representen el momento aplicado frente a la apertura de fisura, en vez de la curvatura. Esta metodología, extensible a hormigón armado, se considera una aproximación más física al análisis de secciones fisuradas y plantea a la hipótesis de fisura plana como ecuación de compatibilidad alternativa a la hipótesis de Navier, que es la normalmente incluida en las normativas. Referencias: [1] S. Gali, K.V.L. Subramaniam. 2018. Multi-linear stress-crack separation relationship for steel fiber reinforced concrete: Analytical framework and experimental evaluation, Theoretical and Applied Fracture Mechanics, 93, 33-43 [2] Tada, H. et al. 1973. The stress analysis of cracks handbook. Del Research Corporation

Relational capability: a study of the Brazilian Agricultural Research Corporation

The Brazilian Agricultural Research Corporation (EMBRAPA) plays an important role in Research and Development (R&D) for generating innovations. Most innovations are generated through R&D alliances with external partners, stimulating relational capability (RC), that is, a construct of strategic management of alliances with propositions for procedures that have not yet been empirically verified. In this context, we investigated how relational capability processes contribute to generating innovations. We conducted qualitative research using a case study based on interviews, document analysis, and observation. Three strategic R&D alliances involving EMBRAPA and external partners constituted the analysis corpus. The main contribution to knowledge advancement is a multidimensional fraProgmework for generating innovations from strategic R&D alliances, based on the empirical evidence of processes of EMBRAPA relational capability and its external partners. This new framework sheds light on how a public research enterprise absorbs knowledge and uncovers the processes of institutionalization and relational capability spillover.

Capacidade relacional: um estudo da Empresa Brasileira de Pesquisa Agropecuária

The Brazilian Agricultural Research Corporation (EMBRAPA) plays an important role in Research and Development (R&D) for generating innovations. Most innovations are generated through R&D alliances with external partners, stimulating relational capability (RC), that is, a construct of strategic management of alliances with propositions for procedures that have not yet been empirically verified. In this context, we investigated how relational capability processes contribute to generating innovations. We conducted qualitative research using a case study based on interviews, document analysis, and observation. Three strategic R&D alliances involving EMBRAPA and external partners constituted the analysis corpus. The main contribution to knowledge advancement is a multidimensional fraProgmework for generating innovations from strategic R&D alliances, based on the empirical evidence of processes of EMBRAPA relational capability and its external partners. This new framework sheds light on how a public research enterprise absorbs knowledge and uncovers the processes of institutionalization and relational capability spillover.

Genetic and morphological characterization of traditional rice and bean varieties from the Pantanal of Mato Grosso, Brazil

Farmers from the district of São Pedro de Joselândia, belonging to the municipality of Barão de Melgaço, Pantanal of Mato Grosso, have been cultivating for some time two rice plant materials and three types of beans that, according to them, are not commercial. For this reason, the objective of this work was to test the originality of the materials by means of genetic and morphological characterization in order to identify whether the nature of the subsamples would be effectively traditional or whether they are varieties already known in the market. Morphological analyzes of the cultivated plants (phenotypic characteristics, cycle and flowering) and seed of the rice subsamples, hereinafter called Agulhinha Vermelho and Branquinho and of the Amarelinho, Rosinha and Roxinho subsamples were performed. Also, the evaluation of distribution of comparative genetic variability with other materials of the same species, already cataloged, was determined. The subsamples were characterized as traditional varieties different from those already cataloged and they are not found in the Nuclear Collection of Rice and Beans of the Brazilian Agricultural Research Corporation (Embrapa). They have distinct morphological characteristics, being potential species for use in the market of new technologies. This should guarantee to the residents of that community that they are breeders of specific materials of cultural heritage adapted to the local conditions.