Humankind is defining a new geological time. The Anthropocene epoch is marked by changes in the geological processes, hydrological regimes, biosphere structure, among other processes, due to human expansion over the landscape worldwide. Biogeochemical cycle’s acceleration, the high load of pollutants in water resources, rampant deforestation, increase in the greenhouse gas emissions to the atmosphere, eutrophication and biodiversity losses are some indications that reflect human’s pressure over several ecosystems, especially aquatic ones. Therefore, here we reviewed some aspects from a huge anthropogenic influence on ecosystems: water pollution. For decades, humankind has increasingly placed demands on aquatic environments without any concern. As an effect, lakes, rivers, and reservoirs are being globally degraded. Although the interactive effects of future anthropic processes are complex, much of current knowledge suggests that these pressures are likely to increase in magnitude and frequency over the next years. Hence, scientific results need to be articulated in an integrative perspective to expand our understanding of the aquatic resources management. The ecological knowledge generated by scientists must be applied to solve environmental problems enabling human progress sustainably. It is urgent to improve communication and understanding among different sectors of society in favor of water management. Therefore, it will be possible to ensure the preservation of natural resources for future generations by using transdisciplinary tools to understand, mitigate and recover the water resources from these anthropogenic pressures.

Reservoirs are globally significant sources of carbon dioxide (CO2) and methane (CH4) to the atmosphere. The patterns of spatial and temporal variability in CO2 and CH4 emission from reservoirs are still poorly studied, especially in tropical regions where hydropower is growing rapidly. We performed spatially resolved measurements of dissolved CO2 and CH4 surface water concentrations and their gas-exchange coefficients (k) to compute diffusive carbon flux from four contrasting tropical reservoirs across Brazil during different hydrological seasons. Diffusive CO2 emissions were higher during the dry season than during the rainy season, whereas there were no consistent seasonal patterns for diffusive CH4 emissions. Our results reveal that the magnitude and the spatial within-reservoir patterns of diffusive CO2 and CH4 flux varied strongly among hydrological seasons. River inflow areas were often characterized by high seasonality in diffusive flux. Areas close to the dam generally showed low seasonal variability in diffusive CH4 flux but high variability in diffusive CO2 flux. Overall, we found that reservoir areas exhibiting highest emission rates (‘hotspots’) shifted substantially across hydrological seasons. Estimates of total diffusive carbon emission from the reservoir surfaces differed between hydrological seasons by a factor up to 7 in Chapéu D’Úvas reservoir, up to 13 in Curuá-Una reservoir, up to 4 in Furnas reservoir, and up to 1.8 in Funil reservoir, indicating that spatially-resolved measurements of gas concentrations and k need to be performed at different hydrological seasons in order to constrain annual diffusive carbon emission.