Microalgae of the continental shelf off Paraná State, southeastern Brazil: a review of studies

The paper reviews the taxonomic and ecological works on marine microalgae (phytoplankton and microphytobenthos) off Paraná State, Southeastern Brazil. Various studies refer to the taxonomy of benthic diatoms. Few descriptive field works in coastal and adjacent shelf waters contribute to the understanding of phytoplankton dynamics in coastal and shelf areas. Patterns of geographic distribution and changes in the phytoplankton community are described in relation to water masses and seasonal variations in the hydrographic regime. During summertime, when warm oligotrophic waters predominate over the shelf, the phytoplankton is nummerically dominated by small phytotlagellates, dinotlagellates, coccolithophorids and filaments of cyanobacteria. During wintertime, the abundance of micro-size diatoms over the shclf increase due to the dominance of cold nutrient-rich waters from the South Atlantic Central Water and wind-driven vertical circulation. The phytoplankton community off Paraná State may be classified into two categorics: the diatom-dominated coastal assemblage, mainly controlled by nutrient inputs from land drainage and ressuspension of bottom sediments, and the tlagellate-dominated shelf assemblage, more affectcd by the seasonality of local hydrographic regime.O trabalho é uma revisão dos estudos taxonômicos e ecológicos das microalgas (planctônicas e bentônicas) realizados no Estado do Paraná. A maioria dos trabalhos sobre microfitobentos são de caráter taxonômico e, basicamente, referem-se à diatomáceas bênticas sobre macroalgas ou fundos lodosos e consolidados. Poucos trabalhos contribuiram para o estudo da dinâmica espaço-temporal do fitoplâncton em áreas costeiras e de plataforma. São descritos os padrões de distribuição geográfica e as mudanças sazonais na comunidade fitoplanctônica em relação ao regime hidrográfico. No verão, quando águas quentes oligotróficas predominam na superfície, o fitoplâncton é numericamente dominado por nanoflagelados, dinoflagelados, cocolitoforídeos e cianobactérias ftlamentosas. No inverno, as diatomáceas do microplâncton são em geral mais abundantes devido ao domínio de águas frias ricas em nutrientes. A comunidade fitoplanctônica da plataforma paranaense pode ser classificada em duas categorias: as associações costeira, sujeitas ao aporte de nutrientes pela drenagem continental e ressuspensão do sedimento, e a comunidade da plataforma afastada da costa, mais afetada pela sasonalidade do regime hidrográfico

A Amazônia Azul: recursos e preservação

The area encompassed by the Brazilian Exclusive Economic Zone (EEZ) and its extensions is estimated to cover a total area of 4.5 million square kilometers, which corresponds to more than half of continental Brazil. This sea area over which Brazil is entitled to have some sort of sovereignty has been named Blue Amazon. Despite the enormous potential of resources existing in this EEZ, such as living resources, mineral resources, energy resources, and non-extractive resources – some of which have already been exploited – the perception of Brazilians as regards their sea and its resources is still incipient. One of the consequences of the lack of maritime mentality is that the exploitation of resources in the Brazilian EEZ is not always carried out in a sustainable mannerA área ocupada pela Zona Econômica Exclusiva (ZEE) brasileira e suas extensões é estimada em 4,5 milhões de quilômetros quadrados, sendo mais do que a metade da área do Brasil continental. Essa área marinha sobre a qual o Brasil exerce alguma forma de soberania tem sido denominada “Amazônia Azul”. Apesar do enorme potencial de recursos existentes na ZEE, tais como recursos vivos, recursos minerais, recursos energéticos e recursos não extrativos, alguns já em exploração, a percepção dos brasileiros a respeito do seu mar e dos seus recursos ainda é incipiente. Uma das consequências da falta de mentalidade marítima é a exploração nem sempre sustentável dos recursos da ZEE brasileir

Wind speed and mesoscale features drive net autotrophy in the South Atlantic Ocean

This is the final version. Available on open access from Elsevier via the DOI in this recordA comprehensive in situ dataset of chlorophyll a (Chl a; N = 18,001), net primary production (NPP; N = 165) and net community production (NCP; N = 95), were used to evaluate the performance of Moderate Resolution Imaging Spectroradiometer on Aqua (MODIS-A) algorithms for these parameters, in the South Atlantic Ocean, to facilitate the accurate generation of satellite NCP time series. For Chl a, five algorithms were tested using MODIS-A data, and OC3-CI performed best, which was subsequently used to compute NPP. Of three NPP algorithms tested, a Wavelength Resolved Model (WRM) was the most accurate, and was therefore used to estimate NCP with an empirical relationship between NCP with NPP and sea surface temperature (SST). A perturbation analysis was deployed to quantify the range of uncertainties introduced in satellite NCP from input parameters. The largest reductions in the uncertainty of satellite NCP came from MODIS-A derived NPP using the WRM (40%) and MODIS-A Chl a using OC3-CI (22%). The most accurate NCP algorithm, was used to generate a 16 year time series (2002 to 2018) from MODIS-A to assess climate and environmental drivers of NCP across the South Atlantic basin. Positive correlations between wind speed anomalies and NCP anomalies were observed in the central South Atlantic Gyre (SATL), and the Benguela Upwelling (BENG), indicating that autotrophic conditions may be fuelled by local wind-induced nutrient inputs to the mixed layer. Sea Level Height Anomalies (SLHA), used as an indicator of mesoscale eddies, were negatively correlated with NCP anomalies offshore of the BENG upwelling fronts into the SATL, suggesting autotrophic conditions are driven by mesoscale features. The Agulhas bank and Brazil-Malvinas confluence regions also had a strong negative correlation between SLHA and NCP anomalies, similarly indicating that NCP is forced by mesoscale eddy generation in this region. Positive correlations between SST anomalies and the Multivariate ENSO Index (MEI) in the SATL, indicated the influence of El Niño events on the South Atlantic Ocean, however the plankton community response was less clear.Natural Environment Research Council (NERC)European Space Agency (ESA)P&D ANP/BRASOILOceanographic Institute of the University of São Paulo (IOUSP

Coastal high-frequency radars in the Mediterranean - Part 1: Status of operations and a framework for future development

Due to the semi-enclosed nature of the Mediterranean Sea, natural disasters and anthropogenic activities impose stronger pressures on its coastal ecosystems than in any other sea of the world. With the aim of responding adequately to science priorities and societal challenges, littoral waters must be effectively monitored with high-frequency radar (HFR) systems. This land-based remote sensing technology can provide, in near-real time, fine-resolution maps of the surface circulation over broad coastal areas, along with reliable directional wave and wind information. The main goal of this work is to showcase the current status of the Mediterranean HFR network and the future roadmap for orchestrated actions. Ongoing collaborative efforts and recent progress of this regional alliance are not only described but also connected with other European initiatives and global frameworks, highlighting the advantages of this cost-effective instrument for the multi-parameter monitoring of the sea state. Coordinated endeavors between HFR operators from different multi-disciplinary institutions are mandatory to reach a mature stage at both national and regional levels, striving to do the following: (i) harmonize deployment and maintenance practices; (ii) standardize data, metadata, and quality control procedures; (iii) centralize data management, visualization, and access platforms; and (iv) develop practical applications of societal benefit that can be used for strategic planning and informed decision-making in the Mediterranean marine environment. Such fit-for-purpose applications can serve for search and rescue operations, safe vessel navigation, tracking of marine pollutants, the monitoring of extreme events, the investigation of transport processes, and the connectivity between offshore waters and coastal ecosystems. Finally, future prospects within the Mediterranean framework are discussed along with a wealth of socioeconomic, technical, and scientific challenges to be faced during the implementation of this integrated HFR regional network