Mainara Gouveia

Scopus Publications

Persistent Lagrangian transport patterns in the Black Sea identified from climatological Lagrangian Coherent Structures
Mainara Biazati Gouveia, Elisaveta Peneva, Irina Gancheva, Emil V. Stanev
Scientific Reports, 2025
Western boundary currents drive sun-coral (Tubastraea spp.) coastal invasion from oil platforms
Stella Correia Cesar Coelho, Douglas Francisco Marcolino Gherardi, Mainara Biazati Gouveia, Marcelo Visentini Kitahara
Scientific Reports, 2022
Most marine species have a planktonic larval phase that benefit from the surface oceanic flow to enhance their dispersion potential. For invasive species, the interaction of environmentally resistant larvae with different flow regimes and artificial substrates can lead to complex larval dispersion patterns and boost geographic expansion. In the Southwest Atlantic, the invasive corals Tubastraea spp. (sun-coral) have been recorded biofouling on oil platforms since the late 1980s. These platforms are considered important vectors for the established populations throughout the Brazilian coast. However, we still do not know how the position of these structures relative to regional flow contribute to the natural dispersion potential of these invaders on a regional scale. Herein, we used an eddy-resolving ocean model (ROMS) and an Individual Based Model (IBM-Ichthyop) to simulate the natural dispersion patterns of sun-coral larvae from all oil platforms on Brazilian oil-producing basins, for the austral summer and winter along 6 years (2010–2015) in 90-day simulations. We found that mortality rates by advection were significantly higher during the winter (p = 0.001) and when sources of larvae were compared throughout this season (p = 1.9 × 10–17). The influence of two western boundary currents and persistent eddy activity contribute to the dispersal of larvae to distances up to 7000 km. The effectiveness of each oil-producing basin as vectors for the entire Brazilian coastline, measured as the percentage of larval supply, highlights the importance of the northern Ceará (59.89%) and Potiguar (87.47%) basins and the more central Camamu (44.11%) and Sergipe-Alagoas (39.20%) basins. The poleward shift of the Southern branch of the South Equatorial Current during the winter causes larvae released from the Sergipe-Alagoas and Camamu basins to enter the North Brazil Current, expanding their dispersion towards the north. The Brazil Current disperses larvae southwards, but strong mesoscale activity prevents their dispersion to the coast, especially for those released from the oil platforms on Campos and Santos basins. Within this complex hydrodynamic setting, a few source areas, like those in the Sergipe-Alagoas and Camamu basins, can potentially contribute to the spread of larvae along nearly all the Brazilian coast. Therefore, oil platforms act as possible chronic sources of sun-coral propagules to the coast, emphasizing the urgency for a more detailed set of actions to control and monitor these invasive exotic species.
Oil spill detection based on texture analysis: how does feature importance matter in classification?
Rodrigo N. Vasconcelos, Carlos A. D. Lentini, André T. Cunha Lima, Luís F. F. Mendonça, Garcia V. Miranda, et al.
International Journal of Remote Sensing, 2022
Persistent meanders and eddies lead to quasi-steady Lagrangian transport patterns in a weak western boundary current
M. B. Gouveia, R. Duran, J. A. Lorenzzetti, A. T. Assireu, R. Toste, et al.
Scientific Reports, 2021
The Brazil Current (BC) is a weak western boundary current flowing along the Southwestern Atlantic Ocean. It is frequently described as a flow with intense mesoscale activity and relatively low volume transport between 5.0 and 10.0 Sv. We use a 13-year eddy-resolving primitive-equation simulation to show that the presence of persistent meanders and eddies leads to characteristic quasi-steady Lagrangian transport patterns, aptly extracted through climatological Lagrangian Coherent Structures (cLCS). The cLCS position the surface expression of the BC core along the 2000-m isobath, in excellent visual agreement with high resolution satellite sea-surface temperature and the model Eulerian mean velocity. The cLCS deformation pattern also responds to zonally persistent cross-shelf SSH transition from positive (high) values near coastline to low (negative) values between 200- and 2000-m and back to positive (high) offshore from the 2000-m isobath. Zonally-paired cyclonic and anticyclonic structures are embedded in this transition, also causing the cLCS to deform into chevrons. An efficient transport barrier is identified close to the 200-m isobath confirmed by limited inshore movement of drogued drifters and accurately indicated by an along slope maxima of climatological strength of attraction. We also show that the persistent cyclonic and anticyclonic structures may induce localized cross-shelf transport. Regions of low climatological strength of attraction coincide with large shelves and with stagnant synthetic trajectories. We also show that cLCS accurately depict trajectories initiated at the location of Chevron’s spill (November 2011) as compared to synthetic and satellite-tracked trajectories, and the outline of the oil from that accident. There is also an agreement between the large-scale oil slicks reaching the Brazilian beaches (from August 2019 to February 2020) and the strength of climatological attraction at the coast. Our work also clarifies the influence of persistent mesoscale structures on the regional circulation. The identification and quantitative description of climatological Lagrangian coherent structures is expected to improve the effectiveness of future emergency response to oil spills, contingency planning, rescue operations, larval and fish connectivity assessment, drifter launch strategies, waste pollutant and marine debris dispersion and destination.
Publisher Correction: Persistent meanders and eddies lead to quasi‑steady Lagrangian transport patterns in a weak western boundary current (Scientific Reports, (2021), 11, 1, (497), 10.1038/s41598-020-79386-9)
M. B. Gouveia, R. Duran, J. A. Lorenzzetti, A. T. Assireu, R. Toste, et al.
Scientific Reports, 2021
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Sar oil spill detection system through random forest classifiers
Marcos Reinan Assis Conceição, Luis Felipe Ferreira de Mendonça, Carlos Alessandre Domingos Lentini, André Telles da Cunha Lima, José Marques Lopes, et al.
Remote Sensing, 2021
A set of open-source routines capable of identifying possible oil-like spills based on two random forest classifiers were developed and tested with a Sentinel-1 SAR image dataset. The first random forest model is an ocean SAR image classifier where the labeling inputs were oil spills, biological films, rain cells, low wind regions, clean sea surface, ships, and terrain. The second one was a SAR image oil detector named “Radar Image Oil Spill Seeker (RIOSS)”, which classified oil-like targets. An optimized feature space to serve as input to such classification models, both in terms of variance and computational efficiency, was developed. It involved an extensive search from 42 image attribute definitions based on their correlations and classifier-based importance estimative. This number included statistics, shape, fractal geometry, texture, and gradient-based attributes. Mixed adaptive thresholding was performed to calculate some of the features studied, returning consistent dark spot segmentation results. The selected attributes were also related to the imaged phenomena’s physical aspects. This process helped us apply the attributes to a random forest, increasing our algorithm’s accuracy up to 90% and its ability to generate even more reliable results.
Do the Brazilian sardine commercial landings respond to local ocean circulation?
Mainara B. Gouveia, Douglas F. M. Gherardi, Carlos A. D. Lentini, Daniela F. Dias, Paula C. Campos
Plos One, 2017

Mainara Gouveia

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Scopus Publications