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Interactions between land use and cover and a basin hydrological regime are complex and dynamics. The identification of trends and changes in rainfall and flow regimes in a region is relevant in water resources planning and management so that environmental, economic and social adversities are avoided. Thus, this study aims to identify possible trends in the historical series of rainfall and fluviometric stations in Rio das Mortes basin, Minas Gerais, Brazil, as well as to relate the modifications in the flow rate behaviour due to changes in land use and cover in the basin between the years of 1985 and 2017. For that, hydrological data were used from the Ibituruna-MG river station and 12 rainfall stations and orbital images from Landsat-5 and Sentinel satellites. Flow rate and precipitation behavior were performed using the nonparametric Mann-Kendall test and the Pettitt's test, while the land use and cover classification was performed in an eCognition Developer® 64 environment. Significant trends were observed in the average of total annual rainfall series and decreasing trends in the average of monthly flow rate series of lowest runoff over the years 1925 to 2014. There were changes in land use and cover in the studied region, however, these were not significant enough to modify the hydrological regime of Rio das Mortes basin during the analysed period. [ABSTRACT FROM AUTHOR]

The investigation of land use changes by anthropic processes, spatially and temporally, is a fundamental tool to establish correlations between landscape patterns and processes and management of the buffer zone of Conservation Units. This study aimed to analyze the forest fragmentation and land use dynamics in the buffer zone of the Rio Doce State Park (PERD), located in Minas Gerais, Brazil, for the year 2015. Its buffer zone was delimited to a radius of 10 km, covering a total area of 128.893,36 ha. Land use classification was based on Landsat 8 image, orbit 217, point 73 and 74, and two types of ecosystems were identified: natural and anthropic. In the thematic mapping, the pressure of the anthropic use over the natural was notified, as well as the high number of forest fragments, which is a negative impact on the resilience required for the conservation of biodiversity and the local Atlantic forest. The fragments have different shapes and sizes and are distributed throughout the buffer zone of the PERD. There is a need to adopt conservation strategies, such as environmental education, reforestation techniques, recovery of degraded areas and ecological corridors. Even with a worrying current scenario, this finding makes it possible to establish an optimistic point for biodiversity conservation, associated with a tendency to reduce the forces of direct changes on natural systems. [ABSTRACT FROM AUTHOR]

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The Território Quilombola Kalunga de Goiás (TKG) was established by law nº. 11,409/GO, and was federally regularized as territory in 2009. Its total area covers three Municipalities of Goiás: Monte Alegre de Goiás, Teresina de Goiás and Cavalcante. There live remaining communities of quilombolas. The present work aims to evaluate the recurrence of fires in this Territory and in its surroundings, doing relationships between land use and land cover and burned areas. For this purpose, were used data generated from satellite images, made available in public databases, and procedures in GIS. During the annualized time, the frequency of fires was moderate. Grassland had the largest proportion of burned areas. [ABSTRACT FROM AUTHOR]

Biofuels are predicted to constitute a large proportion of fuel consumption in the global transport sector under stringent climate mitigation polices in future. In Brazil, sugarcane ethanol has been widely deployed at large scale and an oriented expansion of sugarcane is considered to be a key measure to ensure the expected positive outcomes from biofuels. In this study, more recent and accurate georeferenced information were combined with an enhanced land use classification system to update the original Sugarcane Agroecological Zoning (SAEZ). We also excluded environmentally relevant areas (ERA) in our updated SAEZ to create a new set of reference maps for supporting future prioritization of areas for sugarcane ethanol expansion. We mapped 41.7 Mha as suitable land for sugarcane expansion in center-south region of Brazil, differently from the 50 Mha indicated in the original SAEZ. After excluding the ERA, 33.7 Mha was found to be suitable for sugarcane expansion, of which 20 Mha is currently occupied with pasture lands. About half of these areas were located in Mato Grosso do Sul and Minas Gerais states and an exploratory assessment of two microregions from these states demonstrated the importance of conducting regional assessments to prioritize the areas for a more sustainable sugarcane expansion to meet future bioenergy demands. • Our analysis identified an area 17% smaller than original agro-ecological zoning suitable for sugarcane expansion. • By excluding environmentally relevant areas, the total suitable area for sugarcane expansion is reduced to 33.7 Mha. • About two thirds of that area is currently occupied with pasture lands. • About half of suitable areas occupied with pasture lands are in two Brazilian states. • Local conditions are fundamental for oriented expansion of bioenergy production. [ABSTRACT FROM AUTHOR]

Western Bahia is a critical region in Brazil's recent expansion of agricultural output. Its outstanding increase in production is associated with strong growth in cropland area and irrigation. Here we present analyses of Western Bahian historical changes in land use, including irrigated area, and suitability for future agricultural expansion that respects permanent protection areas and the limits established by the Brazilian Forest Code in the Cerrado biome. For this purpose, we developed a land use and land cover classification database using a random forest classifier and Landsat images. A spatial multicriteria decision analysis to evaluate land suitability was performed by combining this database with precipitation and slope data. We demonstrate that between 1990 and 2020, the region's total agricultural area increased by 3.17 Mha and the irrigated area increased by 193,480 ha. Throughout the region, the transition between the different classes of land use and land cover followed different pathways and was strongly influenced by land suitability and also appears to be influenced by Brazil's new Forest Code of 2012. We conclude that even if conservation restrictions are considered, agricultural area could nearly double in the region, with expansion possible mostly in areas we classify as moderately suitable for agriculture, which are subject to climate hazards when used for rainfed crops but are otherwise fine for pastures and irrigated croplands. [ABSTRACT FROM AUTHOR]

Over the decades, hydropower complexes have been built in several hydrographic basins of Brazil including the Amazon region. Therefore, it is important to understand the effects of these constructions on the environment and local communities. This work presents a land use and land cover change temporal analysis considering a 33-year period (1985–2018) in the direct influence zone of the Braço Norte Hydropower Complex, Brazilian Amazonia, using the Collection 4.1 level 3 of the freely available MapBiomas dataset. Additionally, we have assessed the Brazilian Amazon large-scale deforestation process acting as a land use and land cover change driver in the study area. Our findings show that the most impacted land cover was forest formation (from 414 km2 to 287 km2, a reduction of 69%), which primarily shifted into pasturelands (increase of 664%, from 40 km2 to 299 km2). The construction of the hydropower complex also triggered indirect impacts such as the presence of urban areas in 2018 and the consequent increased local demand for crops. Together with the ongoing large-scale Amazonian deforestation process, the construction of the complex has intensified changes in the study area as 56.42% of the pixels were changed between 1985 and 2018. This indicates the importance of accurate economic and environmental impact studies for assessing social and environmental consequences of future construction in this unique region. Our results reveal the need for adopting special policies to minimize the impact of these constructions, for example, the creation of Protected Areas and the definition of locally-adjusted parameters for the ecological-economic zoning considering environmental and social circumstances derived from the local actors that depend on the natural environment to subsist such as indigenous peoples, riverine population, and artisanal fishermen. [ABSTRACT FROM AUTHOR]