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The Chapada Diamantina region in the São Francisco craton of eastern Brazil is composed of sedimentary successions containing both Mesoproterozoic and Neoproterozoic carbonate levels, making it a key natural laboratory for understanding the fluctuations of Earth’s biogeochemical cycles during its middle age. The ca. 1.4–1.2 Ga Caboclo Formation stromatolites yielded unfractionated δ53Crauth (authigenic) (~–0.54‰ to +0.08‰). Ediacaran cap carbonates and phosphatic stromatolites of the Salitre Formation, on the other hand, yielded fractionated δ53Crauth reaching as high as +0.51‰, suggesting the input of 53Cr-rich Cr(VI), first delivered through meltwater-induced post–snowball Earth fluctuating redox conditions and then through weathering and mobilization under a fully oxygenated environment. The acquired data set highlights the very distinct redox conditions throughout the Proterozoic and reinforces the suggestion that after the Cryogenian global glaciations, Earth’s atmosphere and hydrosphere became progressively oxygenated during the Ediacaran-Cambrian transition.

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RESUMO:A videira ou vinha, pertence à família das Vitaceae, subdivididas nas espécies Parthenocissus quinquefólia e Vitis vinífera, sendo esta última utilizada no cultivo de uvas no mundo. Nos próximos anos o potencial de consumo de vinho será maior que sua produção, necessitando que a produção da matéria prima seja otimizada. A tecnologia é a ferramenta preponderante nesse processo, trazendo consigo um manejo eficiente a partir da agricultura de precisão, com intuito de obter indicadores análogos entre as regiões do Vale do São Francisco no Brasil e Vale do Colchagua no Chile, aprimorando o cultivo. Objetiva-se nesse trabalho, caracterizá-las através da análise de seus elementos agronômicos, topográficos, pedológicos e climáticos. O estudo contou com revisão bibliográfica sobre as duas regiões e coleta de dados agrupados em grupos denominados 1, 2 e 3. Foram discutidas as carências e vantagens agrícolas existentes nas duas regiões, buscando-se o melhoramento do cultivo. Os fatores estudados proporcionaram uma análise eficiente, sendo provadas suas importâncias. A agricultura de precisão proporciona à sociedade diversos benefícios de forma sustentável. Palavras-chave: agricultura de precisão, cultivo de uva, produção de vinho. ABSTRACT:The vine or vineyard, belongs to the family Vitaceae, subdivided in the species Parthenocissus quinquefólia and Vitis vinífera, the latter being used in the cultivation of grapes in the world. In the coming years the wine consumption potential will be higher than its production, requiring the production of the raw material is optimized. Technology is the leading tool in this process, bringing an efficient management from the precision agriculture, seeking to obtain similar indicators between regions of the São Francisco Valley in Brazil and Colchagua Valley in Chile, improving cultivation. The objective of this work is to characterize the two regions by analyzing their agronomic, topographical, soil and climatic conditions. The study included literature review about the two regions and collection of data grouped into groups called 1, 2 e 3. The needs and agricultural advantages existing were discussed in the two regions, seeking the improvement of the cultivation. The factors studied provided efficient analysis, being proven their importance. Precision agriculture provides society with many benefits in a sustainable manner.