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Effects of land use on nitrogen stocks and humic fractions in a Plinthosol of the Brazilian CerradoNARA Subscribed
The replacement of native vegetation may alter soil organic matter (SOM) quality and nitrogen (N) dynamics, because N is one of the main constituents of SOM. This study evaluated N content and stocks in humic fractions across different soil layers (0.00–0.50 m) of a Plinthosol in Tocantins State, Brazil, under different land uses: native Cerrado forest (control), eucalyptus, agriculture, and pasture. Soil samples were collecte...
Drought modulates ozone stress through BVOCs, antioxidant defenses, and metabolic responses in a tropical treeNARA Subscribed
Main conclusion Water limitation attenuated ozone-induced oxidative stress in Eugenia uniflora, maintaining physiological stability and promoting targeted biogenic volatile organic compounds (BVOCs) and metabolic adjustments rather than large-scale disruption. Abstract Tropical forests are increasingly exposed to multiple environmental stressors, yet the combined effects of drought and ozone on native tropical tree species rem...
A decade after the Fundão Dam collapse: key findings from studies in the Doce River basin and adjacent coastal and marine environmentsNARA Subscribed
The Fundão tailings dam marks its 10th year of disaster in 2025, underscoring the need for a critical assessment of the studies related to the impacts on aquatic ecosystems caused by the largest disaster in mining history. In this context, the present study aimed to review articles that, throughout the years, have investigated changes in the Doce River basin, as well as in coastal and marine areas affected by this collapse. We...
Coastal marine ecosystems are key components of biodiversity and ecosystem functioning but have been increasingly degraded by human activities. One of the most severe environmental disasters in Brazil occurred in November 2015, when the Fundão tailings dam collapsed in Mariana (Minas Gerais), releasing approximately 40 million m 3 of iron ore waste into the Rio Doce basin and adjacent coastal environments. To evaluate the long...
Off the Amazon shelf, internal solitary waves (ISWs) generated by internal tides interact with mesoscale eddies, leading to significant modifications in their propagation and structure. For the first time, these interactions are directly observed from repeated high-resolution satellite measurements, notably those provided by the newly launched SWOT (Surface Water and Ocean Topography) mission. The study investigates ISWs detec...
Marine megafauna species are affected by a wide range of anthropogenic threats. To evaluate the risk of such threats, species’ vulnerability to each threat must first be determined. We build on the existing threats classification scheme and ranking system of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species by assessing the vulnerability of 256 marine megafauna species to 23 at‐sea threat...
The ocean region off the Amazon shelf including the shelf break presents a hotspot for internal tide (IT) generation, yet its impact on phytoplankton distribution remains poorly understood. While previous studies have extensively examined the physical characteristics and dynamics of ITs, their biological implications – particularly in nutrient-limited environments – remain underexplored. To address this question, we analyzed a...
Neuroimaging in Cerebellar Ataxias: A Diagnostic ApproachNARA Subscribed
Wave climate variability, including seasonal cycles, long-term trends, and interannual anomalies of wave parameters, was investigated across five latitudinal sectors using ERA5 reanalysis data from 1980 to 2023. Pronounced seasonal cycles were observed in both Northern and Southern Hemisphere sectors, although the variability was more marked in the Northern Hemisphere. In contrast, the tropical region exhibited comparatively s...
Turbulent dissipation along contrasting internal tide paths off the Amazon shelf from AMAZOMIXOA Marine
The Amazon shelf break is a key oceanic region where strong internal tides (ITs) are generated, playing a substantial role in climate processes and ecosystems through vertical dissipation and mixing. During the AMAZOMIX survey (2021), currents, hydrography, and turbulence were measured over the M2 tidal period (12.42 h) at multiple stations along both high (HTE) and low (LTE) tidal energy paths, covering IT generation and prop...