Multi-Wavelength Calibration of a Low-Cost High-Range Turbidimeter: Analysis of the Dispersion Regime Laiz R. Ventura, Alexandre E. Santos, Gabriela V. Buraschi, José L. Paralovo, Marcos N. Gallo, Luiz G. Guimarães, Carlos E. Fellows ACS Omega, 2025 Turbidimetry, a method for assessing fluid clarity by quantifying suspended particle levels, plays an important role in various fields, including environmental surveillance, sediment measurements, water quality management, and diverse industrial sectors. Various optical instruments are commercially available, normally called turbidimeter. However, no generic calibration that can be used to convert the turbidimeter output to NTU is possible. This work presents the development of a low-cost multiwavelength turbidimeter designed for high-range turbidity measurements (0.5–4000 NTU) in visible and near-infrared spectra (500–1000 nm). Using formazin solution as a turbidimetric standard and introducing the calibration factor concept, we were able to determine the identification of multiple calibration zones of the developed sensor. For calibration experiments, a portable spectrometer was used to measure the transmitted light, thereby obtaining a spectrum associated with each standard. Then, analysis of the obtained spectra was performed, enabling characterization of the calibration method employed in the study. Considering various wavelengths in the analysis, the results suggest that the present methodology has the potential to develop environmental monitoring practices and water quality control. More specifically, turbidity measurements can be performed in a wide range of NTU and wavelength values, suggesting the feasibility of conducting analyses over an extensive turbidity spectrum.
Sensitivity analysis of incoming sediment load to the reservoirs of the Paranaíba River basin: effects of climate change Anderson Braga Mendes, Daniel Andres Rodrigues, Marcos Gallo Revista Ambiente E Agua, 2025 Climate change poses significant challenges to reservoir sustainability by altering streamflow regimes and intensifying sediment dynamics. This study provides an integrated assessment of the sensitivity of reservoirs in the Paranaíba River basin to increases in incoming sediment load under climate change scenarios that project higher mean annual streamflow. The system‑level assessment covered 64 dams and 47 hydrosedimentometric monitoring stations in operation in the basin at the end of 2024. For each reservoir, stylized climate-change scenarios applied +1%, +5%, and +10% to the annual mean discharge, with increments redistributed across the daily series. Total sediment loads were computed from station-specific power-law rating curves using Colby’s 1957 simplified method; reservoir trap efficiency followed Churchill and Brune. Impacts are heterogeneous across reservoirs; anthropogenic pressure, particularly urbanization, modulates the sensitivity to discharge increases: sub-basins with higher urbanization show larger responses: the total incoming sediment load increased by up to 32.8% at Lago Paranoá, the most affected site owing to the intense urbanization of its drainage area, which includes Brasília and surrounding cities, in contrast to five reservoirs under lower anthropogenic pressure, such as Santa Maria, near the springs of the Ribeirão do Torto. It explicitly accounts for interactions among multiple projects and addresses the lack of system‑scale analyses for cascade reservoirs.Keywords: cascade reservoirs, climate change, incoming sediment load, Paranaíba river.
In treacherous waters: detection of colistin-resistant bacteria in water and plastic litter from a recreational estuary Gabrielle da Silva Oliveira Alves, Anna Luiza Bauer Canellas, Marcos N Gallo, Susana Beatriz Vinzon, Marinella Silva Laport Letters in Applied Microbiology, 2024 Colistin resistance poses a major therapeutic challenge and resistant strains have now been reported worldwide. However, the occurrence of such bacteria in aquatic environments is considerably less understood. This study aimed to isolate and characterize colistin-resistant strains from water and plastic litter collected in an urban recreational estuary. Altogether, 64 strains with acquired colistin resistance were identified, mainly Acinetobacter spp. and Enterobacter spp. From these, 40.6% were positive for at least one mcr variant (1–9), 26.5% harbored, extended-spectrum beta-lactamases, 23.4% harbored, sulfonamide resistance genes, and 9.3% harbored, quinolone resistance genes. merA, encoding mercury resistance, was detected in 10.5% of these strains, most of which were also strong biofilm producers. The minimum inhibitory concentration toward colistin was determined for the mcr-positive strains and ranged from 2 to ≥512 µg ml−1. Our findings suggest that Gram-negative bacteria highly resistant to a last-resort antimicrobial can be found in recreational waters and plastic litter, thereby evidencing the urgency of the One Health approach to mitigate the antimicrobial resistance crisis.
Evaluation of a High Resolution WRF Model for Southeast Brazilian Coast: The Importance of Physical Parameterization to Wind Representation Layrson de Jesus Menezes Gonçalves, Júlia Kaiser, Ronaldo Maia de Jesus Palmeira, Marcos Nicolás Gallo, Carlos Eduardo Parente Atmosphere, 2024 This study assesses the performance of the Weather Research and Forecasting (WRF) model using a high-resolution spatial grid (1 km) with various combinations of physical parameterization packages to simulate a severe event in August 2021 in the southeastern Brazilian coast. After determining the optimal set of physical parameterizations for representing wind patterns during this event, a year-long evaluation was conducted, covering forecast horizons of 24, 48, and 72 h. The simulation results were compared with observational wind data from four weather stations. The findings highlight variations in the efficacy of different physical parameterization sets, with certain sets encountering challenges in accurately depicting the peak of the severe event. The most favorable results were achieved using a combination of Tiedtke (cumulus), Thompson (microphysics), TKE (boundary layer), Monin-Obukhov (surface layer), Unified-NOAH (land surface), and RRTMG (shortwave and longwave radiation). Over the one-year forecasting period, the WRF model effectively represented the overall wind pattern, including forecasts up to three days in advance (72-h forecast horizon). Generally, the statistical metrics indicate robust model performance, even for the 72-h forecast horizon, with correlation coefficients consistently exceeding 0.60 at all analyzed points. While the model proficiently captured wind distribution, it tended to overestimate northeast wind speed and gust intensities. Notably, forecast accuracy decreased as stations approached the ocean, exemplified by the ATPM station.
Meteorological Signal on Hydrodynamics in the Ilha Grande and Sepetiba Bays: Lag Effects and Coastal Currents Nair Emmanuela da Silveira Pereira, Susana Beatriz Vinzón, Marcos Nicolás Gallo, Mariela Gabioux Hydrology, 2024 On the southeastern coast of Brazil, the bays of Ilha Grande and Sepetiba are linked by the Ilha Grande Channel, where remarkably strong currents have been consistently observed. Tidal forces cannot explain the strength of these currents. Previous researchers have focused on investigating factors like baroclinic effects due to salinity differences or seiches between two basins without a conclusive answer. This study aims to elucidate the role of remote meteorological effects within this complex hydrodynamic system. A numerical approach with a coastal model nested within an ocean model was employed, enabling an in-depth examination of the intricate interplay between meteorological and tidal forcings. The study revealed a significant finding: the lag in signal propagation plays a pivotal role in determining how these signals impact the dynamics of the bays. The astronomical signal exhibits a minimal lag along the coast (1 min) and leads to water level differences between the sea and the coastline, resulting in the generation of tidal currents at the bay entrances. On the other hand, the remote meteorological signal, with a stronger signal lag along the coast (4.92 h), leads to the creation of a water level difference between the bay entrances, inducing significant fluxes along the narrow Ilha Grande Channel.
The role of waves in the resuspension and transport of fine sediment and mine tailings from the Fundão Dam failure, Doce River, Brazil Susana Beatriz Vinzon, Marcos Nicolas Gallo, Mariela Gabioux, Diego Luiz Fonseca, Fernanda Minikowski Achete, Renato David Ghisolfi, Guilherme Nogueira Mill, Sabrina Aparecida Ramos da Fonseca, Valéria da Silva Quaresma, Kyssyanne Samihra Santos Oliveira, Guilherme Brigagão, Léo Gonçalves Machado International Journal of Sediment Research, 2024 In one of the world's worst mining disasters, after flowing 670 km down the Doce River, about 20 million m3 of tailings reached the coast of Brazil in November 2015. The occurrence of persistent northerly winds favored the detachment of the river plume from the coastline and its displacement southward. However, observations of the sediment plume along the coast during the year following the breach, using aerial photographs, indicated that the plume is more extensive and persistent in a northerly direction. Previous studies have shown that although the most persistent winds are from the northern sector (70%), there is a greater incidence of waves from the southern sector (62%), especially with greater heights and periods. In this research, the effect of gravity waves on the transport of sediments is investigated, and, therefore, tailings from the Doce River and deposited on the adjacent inner continental shelf, mixed with the fluvial mud deposit also are investigated. Two mechanisms were investigated: 1) the effect of waves on sediment resuspension and their combination with tidal and wind forcings, using a two-dimensions in the horizontal directions (2DH) numerical model within the DELFT3D software, and 2) the capture of the fluvial plume by littoral drift, calculated by means of analytical models using data from wave propagation modeling. Both mechanisms were studied for 2019, also considering two major meteorological events in the region. Both effects were relevant for the northward dispersion of fine sediment, highlighting the effect of waves on the potential for northward transport of tailings towards the Abrolhos Bank.
Mud density prospection using a tuning fork Valentina Groposo, Rodrigo L. Mosquera, Francisco Pedocchi, Susana B. Vinzón, Marcos Gallo Journal of Waterway Port Coastal and Ocean Engineering, 2015
Marés fluviais: Variação espaço-temporal da assimetria no estuário do Rio Amazonas PH Trigo Rosa, V Moura, M Gabioux, MN Gallo, S Vinzon, JD Caprace Ribagua, 1-17 , 2026 2026
Multi-Wavelength Calibration of a Low-Cost High-Range Turbidimeter: Analysis of the Dispersion Regime LR Ventura, AE Santos, GV Buraschi, JL Paralovo, MN Gallo, ... ACS omega 10 (44), 52418-52428 , 2025 2025
Widespread occurrence of mobile colistin resistance genes in Brazilian marine environments RC Brunelli, TV de Jesus Carvalho Baptista, ... Ocean Microbiology 1 (1), 3 , 2025 2025 Citations: 2
Análise de sensibilidade da carga de sedimentos aportada nos reservatórios da bacia do rio Paranaíba: efeitos das mudanças climáticas AB Mendes, DA Rodriguez, M Gallo Revista Ambiente & Água 20, e3123 , 2025 2025
Sensitivity analysis of incoming sediment load to the reservoirs of the Paranaíba River basin: effects of climate change AB Mendes, DA Rodriguez, M Gallo Revista Ambiente & Água 20, e3123 , 2025 2025
Predicting storm surge extremes on the Southeast Brazilian Coast: Long-term projections with neural networks CLG Kaufmann, MN Gallo, R De Camargo Regional Studies in Marine Science 79, 103846 , 2024 2024 Citations: 6
In treacherous waters: detection of colistin-resistant bacteria in water and plastic litter from a recreational estuary GSO Alves, ALB Canellas, MN Gallo, SB Vinzon, MS Laport Letters in Applied Microbiology 77 (9), ovae082 , 2024 2024 Citations: 7
Estratégia de aninhamento de modelos espectrais para reconstituição do clima de ondas em regiões costeiras complexas: Terminal da Ilha Guaíba (RJ-Brasil) GCM Dos Passos, PHT Rosa, J Kaiser, MN Gallo, CE Parente, ... Ribagua 11 (2), 2497230 , 2024 2024
Evaluation of a High Resolution WRF Model for Southeast Brazilian Coast: The Importance of Physical Parameterization to Wind Representation LJM Gonçalves, J Kaiser, RMJ Palmeira, MN Gallo, CE Parente Atmosphere 15 (5), 533 , 2024 2024 Citations: 4
The role of waves in the resuspension and transport of fine sediment and mine tailings from the Fundão Dam failure, Doce River, Brazil SB Vinzon, MN Gallo, M Gabioux, DL Fonseca, FM Achete, RD Ghisolfi, ... International Journal of Sediment Research 39 (1), 44-60 , 2024 2024 Citations: 10
Meteorological signal on hydrodynamics in the Ilha Grande and Sepetiba Bays: lag effects and coastal currents NES Pereira, SB Vinzón, MN Gallo, M Gabioux Hydrology 11 (2), 15 , 2024 2024 Citations: 9
Meteorological Signal on Hydrodynamics in the Ilha Grande and Sepetiba Bays: Lag Effects and Coastal Currents P NEdS, SB Vinzón, MN Gallo, M Gabioux 2023
Predicting significant wave height with artificial neural networks in the South Atlantic Ocean: a hybrid approach P Marangoni Gazineu Marinho Pinto, R Martins Campos, MN Gallo, ... Ocean dynamics 73 (6), 303-315 , 2023 2023 Citations: 12
Erosive and accretive response of a natural beach to storm events F Fabián Criado Sudau, À Fernandez-Mora, J Soriano-González, M Gallo, ... EGU General Assembly Conference Abstracts, EGU-16017 , 2023 2023
Erosive and accretive response of a natural beach to storm events FFC Sudau, À Fernandez-Mora, J Soriano-González, M Gallo, ... EGU23 , 2023 2023
Hydro-morphodynamics of a dredged tidal canal, Fundão Canal-RJ, Brazil GV Buraschi, MN Gallo Journal of South American Earth Sciences 112, 103603 , 2021 2021 Citations: 4
Implementación de Modelos Digitales de Elevación (MDE) para la simulación hidrodinámica bidimensional del escurrimiento en un tramo del río Salado (Santa Fe). Caso: crecida del … M Imhoff 2021
Morphological behavior of the Magdalena River delta (Colombia) due to intra and interannual variations in river discharge B Ávila, MN Gallo Journal of South American Earth Sciences 108, 103215 , 2021 2021 Citations: 16
Tidal inlet short-term morphodynamics analysed trough the tidal prism-longshore sediment transport ratio criterion RAG Silva, MN Gallo, PCC Rosman, ICM Nogueira Geomorphology 351, 106918 , 2020 2020 Citations: 15
MOST CITED SCHOLAR PUBLICATIONS
Generation of overtides and compound tides in Amazon estuary MN Gallo, SB Vinzon Ocean Dynamics 55 (5), 441-448 , 2005 2005 Citations: 197
Dissolved and particulate heavy metals in the Salado River (Santa Fe, Argentina) M Gallo, A Trento, A Alvarez, H Beldoménico, D Campagnoli Water, Air, and Soil Pollution 174 (1), 367-384 , 2006 2006 Citations: 48
Structure and position of the bottom salinity front in the Amazon Estuary E Molinas, SB Vinzon, C de Paula Xavier Vilela, MN Gallo Ocean Dynamics 64 (11), 1583-1599 , 2014 2014 Citations: 35
Laboratory evaluation of two LISST-25X using river sediments L Filippa, L Freire, A Trento, AM Álvarez, M Gallo, S Vinzón Sedimentary Geology 238 (3-4), 268-276 , 2011 2011 Citations: 28
A influência da vazão fluvial sobre a propagação da maré no estuário do rio amazonas MN Gallo Sc., Federal University of Rio de Janeiro, RJ, Brasil , 2004 2004 Citations: 27
Assessing rheological properties of fluid mud samples through tuning fork data DL Fonseca, PC Marroig, JC Carneiro, MN Gallo, SB Vinzón Ocean Dynamics 69 (1), 51-57 , 2019 2019 Citations: 23
Beach morphodynamic response to a submerged reef D Duarte Nemes, F Fabián Criado-Sudau, M Nicolás Gallo Water 11 (2), 340 , 2019 2019 Citations: 22
Estudo numérico do escoamento em planícies de marés do canal Norte (estuário do rio Amazonas) MN Gallo, SB Vinzon Ribagua 2 (1), 38-50 , 2015 2015 Citations: 21
Rip currents dynamic of a swell dominated microtidal beach FF Criado-Sudau, DD Nemes, MN Gallo Journal of Coastal Research 92 (SI), 121-127 , 2019 2019 Citations: 20
Mud density prospection using a tuning fork V Groposo, RL Mosquera, F Pedocchi, SB Vinzón, M Gallo Journal of Waterway, Port, Coastal, and Ocean Engineering 141 (5), 04014047 , 2015 2015 Citations: 17
Morphological behavior of the Magdalena River delta (Colombia) due to intra and interannual variations in river discharge B Ávila, MN Gallo Journal of South American Earth Sciences 108, 103215 , 2021 2021 Citations: 16
Characterisation of the suspended particulate matter in a stratified estuarine environment employing complementary techniques LP Thomas, BM Marino, RN Szupiany, MN Gallo Continental Shelf Research 148, 37-43 , 2017 2017 Citations: 16
Tidal inlet short-term morphodynamics analysed trough the tidal prism-longshore sediment transport ratio criterion RAG Silva, MN Gallo, PCC Rosman, ICM Nogueira Geomorphology 351, 106918 , 2020 2020 Citations: 15
Estimation of suspended sediment concentration by acoustic scattering: an experimental and theoretical analysis for spherical particles BC Xavier, IO Silva, LG Guimarães, MN Gallo, CP Ribeiro, ... Journal of soils and sediments 14 (7), 1325-1333 , 2014 2014 Citations: 15
Strategies for measuring fluid mud layers and their rheological properties in ports JC Carneiro, DL Fonseca, SB Vinzon, MN Gallo Journal of Waterway, Port, Coastal, and Ocean Engineering 143 (4), 04017008 , 2017 2017 Citations: 14
Predicting significant wave height with artificial neural networks in the South Atlantic Ocean: a hybrid approach P Marangoni Gazineu Marinho Pinto, R Martins Campos, MN Gallo, ... Ocean dynamics 73 (6), 303-315 , 2023 2023 Citations: 12
The role of waves in the resuspension and transport of fine sediment and mine tailings from the Fundão Dam failure, Doce River, Brazil SB Vinzon, MN Gallo, M Gabioux, DL Fonseca, FM Achete, RD Ghisolfi, ... International Journal of Sediment Research 39 (1), 44-60 , 2024 2024 Citations: 10
Meteorological signal on hydrodynamics in the Ilha Grande and Sepetiba Bays: lag effects and coastal currents NES Pereira, SB Vinzón, MN Gallo, M Gabioux Hydrology 11 (2), 15 , 2024 2024 Citations: 9
