Global climate change, related to the greenhouse gases emission, impacts hydroelectric power generation mainly due to the increase in air temperature and changes in the precipitation patterns. As a consequence, it affects basin evapotranspiration process, runoff, sediment transport as well as evaporation of reservoirs. This study analysed the current and future Brazilian context of hydroelectric reservoirs and investigated the potential impacts of climate change on hydropower generation and possible mitigation adjustments, giving relevant examples from around the world. Moreover, it is key to consider other factors that influence the availability of water resources such as: (a) upstream development of reservoirs, mainly the development of agricultural systems, which can contribute to increased water demand; (b) changes in land use, which can have an impact on soil degradation and sediment transport. Hydroelectric dams are a possible alternative to mitigate the impacts of climate change considering that those impacts could generate the need of adaptive actions. The assessment of climate change impacts' projections anticipates possible future scenarios and can assist in strategic planning together with the definition of adaptive operational policies.

No escopo daquilo que chamamos de geotecnologias há inúmeros formatos distintos de softwares e aplicativos, que envolvem desde a cartografia digital, a webcartografia, até o geoprocessamento e o trabalho com imagens digitais de sensoriamento remoto. Contudo, nem todas essas ferramentas estão ao alcance das escolas de ensino básico ou foram pensadas para o ensino de conteúdos de cartografia nesse nível. A despeito disso, hoje há inúmeras possibilidades de se utilizar as geotecnologias no ensino-aprendizagem de cartografia e, de forma mais abrangente, da própria geografia escolar. Mas é preciso separar o "joio do trigo" nesse universo de softwares e aplicativos, a fim de desvendar as possibilidades e restrições que eles apresentam. Também é preciso considerar a realidade escolar, a formação e capacitação dos professores, além do nível de acessibilidade dos estudantes a essas tecnologias. Os smartphones, a geração atual de aparelhos celulares com acesso à internet, são instrumentos especialmente oportunos para se superar algumas dessas barreiras. Essas limitações e perspectivas de trabalho são discutidas no presente artigo, tendo como principal exemplo o Google Earth. PALAVRAS-CHAVE Geotecnologias. Ensino. Cartografia. THE GEOTECHNOLOGIES AND THE CARTOGRAPHY EDUCATION IN SCHOOLS: potentialities and constraintsABSTRACTGeotechnology has many different software and application formats, ranging from digital mapping, webcartography, to geoprocessing and remote sensing. However, not all of these tools are within the reach of elementary schools or were designed for the teaching of cartography and geography content. In spite of this, today there are many possibilities of using geotechnologies in the teaching-learning of cartography and, more comprehensively, of the geography itself. But we must separate wheat from the chaff in this universe of software and applications in order to unravel the possibilities and constraints they present. It is also necessary to consider the school reality, the training and qualification of teachers, and the level of accessibility of students to these technologies. Smartphones, the current generation of mobile phones handsets with access to the Internet, are particularly timely tools to overcome some of these barriers. These limitations and perspectives of work are discussed in this article, having as main example Google Earth. KEYWORDS Geotechnology. Geography teaching. Cartography. ISSN: 2236-3904REVISTA BRASILEIRA DE EDUCAÇÃO EM GEOGRAFIA - RBEGwww.revistaedugeo.com.br - revistaedugeo@revistaedugeo.com.br

Over the last few years, the operation of the Furnas Hydropower Plant (HPP) reservoir, located in the Grande River Basin, has been threatened due to a significant reduction in inflow. In the region, hydrological modelling tools are being used and tested to support decision making and water sustainability. In this study, the streamflow was modelled in the area of direct influence of the Furnas HPP reservoir, and the Soil and Water Assessment Tool (SWAT) model performance was verified for studies in the region. Analyses of sensitivity and uncertainty were undertaken using the Sequential Uncertainty Fitting algorithm (SUFI-2) with a Calibration Uncertainty Program (SWAT-CUP). The hydrological modelling, at a monthly scale, presented good results in the calibration (NS 0.86), with a slight reduction of the coefficient in the validation period (NS 0.64). The results suggested that this tool could be applied in future hydrological studies in the region of study. With the consideration that special attention should be given to the historical series used in the calibration and validation of the models. It is important to note that this region has high demands for water resources, primarily for agricultural use. Water demands must also be taken into account in future hydrological simulations. The validation of this methodology led to important contributions to the management of water resources in regions with tropical climates, whose climatological and geological reality resembles the one studied here.

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Usualmente empregadas pelos povos tradicionais, as queimadas também têm sido utilizadas para o desmatamento de vegetação natural e incorporação de atividades agropecuárias. Diante desse contexto, tem-se como objetivo analisar a distribuição espaço-temporal dos focos de queimadas no bioma Cerrado no período de 1999 a 2018, verificando sua ocorrência entre os diferentes tipos de cobertura e uso do solo, no intuito de avaliar a hipótese de que a prática de queimadas esteja recorrentemente associada à desmatamentos e à implantação de atividades agropecuárias. Para tanto, foram compilados, organizados e processados em ambiente SIG, arquivos vetoriais de focos de queimadas, a partir do Banco de Dados de Queimadas (BDQ/INPE), e arquivos raster de mapeamentos de cobertura e uso do solo do Cerrado, elaborados e disponibilizados pelo Projeto MapBiomas, ambos dados referente ao bioma Cerrado e ao recorte temporal de 1999 a 2018. Em termos médios, verifica-se a ocorrência de 65.513 focos anuais de queimadas, porém, em alguns anos a quantidade de queimadas atinge o montante de 137.918 focos, como visto em 2007. Há uma concentração das queimadas no período seco, especialmente, no trimestre agosto-setembro-outubro, que responde por 72% das ocorrências anuais. A maior densidade de queimadas é percebida ao longo da fronteira agrícola na região do MATOPIBA e próxima ao Arco do Desmatamento, nos estados do Maranhão, Tocantins e de Mato Grosso, ao passo que evidencia-se a maior incidência das queimadas sobre determinadas classes de cobertura e uso do solo, sobretudo representadas por formações savânicas e campestres.  Space-temporal distribution of fires in the Cerrado biome (1999/2018) and their occurence according to different types of coverage and soil uses A B S T R A C TUsually employed by traditional communities, fires have also been used to deforest and incorporate agricultural activities. Given this context, the objective is to analyze the spatio-temporal distribution of the fires in the Cerrado biome, from 1999 to 2018, verifying their occurrence between the different types of cover and land use, in order to assess the hypotheses that the practice of fires is recurrently associated with deforestation and the implementation of agricultural activities. For this purpose, were compiled, organized and processed in a GIS environment, fires focus from the Burn Database of the National Institute for Space Research and mappings of cover and land use, elaborated and availabled by the MapBiomas Project, both data referring to the Cerrado biome and over the years 1999 to 2018. On average, there are 65,513 annual fires, but in some years the amount of burns reaches the amount of 137,918 – as seen in 2007. There is a concentration of fires in the dry period, mainly in the August-September-October, which accounts for 72% of annual fires. The highest density of fires occurs mainly along the agricultural frontier in the MATOPIBA region and close to the Arc of Deforestation, specifically in the states of Maranhão, Tocantins and Mato Grosso, while there is a greater incidence of fires on certain classes of coverage and land use, especially represented by savanna and grassland formation, which corroborates the hypothesis of the use of fires to convert vegetation cover into anthropic uses.Keywords: Fires, Cerrado, Cover and land use.