Recent evidence suggests that Brazilian Cerrado has been largely converted, mainly due to agribusiness activities and urbanization. Thus, the present work aimed to obtain the diagnosis of a watershed characterized by ...
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Recent evidence suggests that Brazilian Cerrado has been largely converted, mainly due to agribusiness activities and urbanization. Thus, the present work aimed to obtain the diagnosis of a watershed characterized by the expansion of sugar cane fields in the Brazilian Cerrado (Southeastern), employing integrity landscape indicators (Hemeroby, Urbanity Index, landscape Vulnerability Index, and Water Quality Index) to verify the landscape naturalness, and the consequences of these actions to the ecosystem services provision. Remote sensing data for the years 1998, 2008, and 2018 were employed to verify the land-use changes in the Feijão River watershed (southeastern Brazil), as well as a matrix that considers the land use typologies and their capability to provide ecosystem services. The study area is classified as mixed land use, with the main categories related to agribusiness (sugar cane, pasture, bare soil). The Hemeroby and Urban Index denote naturalness declines over the years, and the observed patterns negatively impact ecosystem service provision. landscape Vulnerability Index and Water Quality Index demonstrated that remaining vegetation cannot effectively retain pollutants, and severe impairments in the resilience of natural components of key ecosystem service providers (i.e. water and native vegetation) were observed. The results allowed the identification of priority areas for recovery and the maintenance of ecosystem services in agricultural lands.
The intensification of anthropic uses (i.e., increase of the hemerobic condition) threatens the remnants of native vegetation due to the reduction of its self-regulation capacity. In this research, the Distance to Nat...
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The intensification of anthropic uses (i.e., increase of the hemerobic condition) threatens the remnants of native vegetation due to the reduction of its self-regulation capacity. In this research, the Distance to Nature (D2N) index for land use and land cover was applied in the Río Grande de Comitán watershed (Southern Mexico) to answer the following questions: 1) What were the land use dynamics observed in the Rio Grande de Comitán watershed in the trajectory through 1999, 2009 and 2019? 2) Does the subcategorization of the D2N allow one to identify which anthropic uses influence more the territorial expression of the watershed? To answer these questions, we performed a supervised classification of land use and land cover was performed in this watershed, and for the D2N index, the classification was simplified to three-category scale for the subcategorization of the anthropic component. Through Principal Component Analysis (PCA), we identified that agricultural anthropogenic use had the greatest influence on territorial expression. The reported scenario indicates a trend of gradual and continuous reduction of naturalness over the last 20 years. Additionally, the D2N index proved to be a useful tool to demonstrate both the anthropic impact, with the simplified scale, and the component that most influences the territory, by subcategorizing the anthropic scale.
The development of clean energy sources is a subject in focus and boosts fuel cells for research. In this context, studies on proton conductive membranes have an important role. In the present work two groups of membr...
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The development of clean energy sources is a subject in focus and boosts fuel cells for research. In this context, studies on proton conductive membranes have an important role. In the present work two groups of membranes were synthetized: one contained SPEEK/SnO2 (varying the content of tin oxide from 2%, 4% and 6%) and the other with SPEEK/SnO2/HPW. The change in the membrane structure was characterized by X-ray diffraction, the swelling in water and ethanol solution uptake test, thermal stability using TGA, change in Tg in DSC, the selective permeability by pervaporation test in water and the solution ethanol and proton conductivity by impedance spectroscopy. Through these analyses, it is possible to verify some effects: the tin oxide particles reduced the Tg membranes, they also controlled the membranes swelling in water and kept it approximately 30% lower than the pure SPEEK swelling and finally, among the tin oxide quantities tested in the membranes, it was reached 67.8 mS/cm as maximum value of proton conductivity.
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