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1.
Mar Pollut Bull ; 200: 116090, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38316101

RÉSUMÉ

Microplastics have accumulated in the environment since plastic production began, with present-day observations that range from marine trenches to mountains. However, research on microplastics has only recently begun so it is unclear how they have changed over time in many oceanic regions. Our study addressed this gap by quantifying the temporal and spatial dynamics of microplastics in two deep-water regions of the Gulf of Mexico (GOM). We isolated agglutinated foraminifera from sediment cores and assessed microplastics that were incorporated into their tests. Our results indicated that microplastics were incorporated by agglutinated foraminifera after plastic production began. Microplastics were higher at deep-water sites and closer to the Mississippi River. This study confirms the presence of microplastic incorporation into agglutinated foraminifera tests and investigates microplastics in deep-water sediments in the GOM. Additional work is needed to fully identify the distribution of microplastics across the GOM and other oceanic basins.


Sujet(s)
Foraminifera , Polluants chimiques de l'eau , Microplastiques , Matières plastiques , Surveillance de l'environnement/méthodes , Golfe du Mexique , Polluants chimiques de l'eau/analyse , Sédiments géologiques , Eau
2.
Mar Environ Res ; 195: 106340, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38232436

RÉSUMÉ

In recent years, the region surrounding Sepetiba Bay (SB; SE Brazil) has become a hub of intense urban expansion and economic exploitation in response to ore transport and industrial and port activities. As a result, contaminants have been introduced into the bay, leading to an overall worsening of the environmental quality. The present work applies for the first time a foraminiferal morphology-based approach (M) and eDNA-based metabarcoding sequencing (G), along with geochemical data to assess the ecological quality status (EcoQS) in the SB. Principal component analysis shows that the eDNA and morphospecies diversity as well as most of the taxa relative abundance decline in response to the environmental stress (ES) gradient related to total organic carbon (TOC) and metal pollution. Based on ecological indices, Exp(H'bc) (G), Exp(H'bc) (M), foraminifera ATZI marine biotic index (Foram-AMBI), Foram Stress Index (FSI), and geochemical indices (TOC and Potential Ecological Risk Index), the lowest values of EcoQS (i.e., bad to moderate) are inferred in the innermost part of the SB. Despite minor discrepancies among the six EcoQS indices, an agreement has been found for 63% of the stations. To improve the agreement between the ecological indices, it is necessary to fill the gap in species ecology; information on the ecology of many species is still unknown. This work reinforces the importance of molecular analysis and morphological methods in environmental impact studies and confirms the reliability of foraminiferal metabarcoding in EcoQS assessment. This is the first study evaluating the EcoQS in the South Atlantic by using combined foraminiferal eDNA metabarcoding with morphological data.


Sujet(s)
Foraminifera , Foraminifera/génétique , Surveillance de l'environnement/méthodes , Brésil , Baies (géographie) , Reproductibilité des résultats , Biodiversité , Sédiments géologiques/composition chimique
3.
Microb Ecol ; 86(4): 2802-2818, 2023 Nov.
Article de Anglais | MEDLINE | ID: mdl-37594520

RÉSUMÉ

Coastal areas are often intervened by anthropic activities, which increase the contamination of toxic agents such as heavy metals. This causes adverse morphological effects on benthic microorganisms, such as foraminifera. This group is one of the most susceptible to environmental deterioration, so they can be used as pollution biomarkers by identifying shell abnormalities. Therefore, 28 sediment samples from northern Chile were analyzed, calculating the Abnormality Index-FAI and its spatio-temporal distributions in benthic foraminifera, as well as the minimum and maximum abnormality percentages and their relationship with heavy metal concentrations, using a generalized non-linear model and a principal component analysis. The results indicated a proportion of abnormal shells within the ranges described for polluted areas conditions, revealing environmental stress conditions. This reflected a change in the environmental conditions in the most recent sediments of the bay. The highest FAI values were observed to the southwest of the bay, caused by the local current system. The species Bolivina seminuda, Buliminella elegantissima, and Epistominella exigua presented a greater number of deformities, allowing them to be used as contamination biomarkers. A significant correlation was found between Ti, Mn, Ni, Va, and Ba with decreased chamber sizes, wrong coiling, scars, and number of abnormality types. This suggests the effect of the particular geochemical conditions of the area on the heavy metals that cause toxic effects on foraminifera. These analyses are an efficient tool for identifying the effects of environmental stress before they occur in higher organisms, mitigating the environmental impact on marine biodiversity.


Sujet(s)
Foraminifera , Métaux lourds , Polluants chimiques de l'eau , Polluants chimiques de l'eau/analyse , Sédiments géologiques/composition chimique , Foraminifera/composition chimique , Surveillance de l'environnement/méthodes , Métaux lourds/toxicité , Métaux lourds/analyse , Marqueurs biologiques
4.
Mar Pollut Bull ; 194(Pt A): 115225, 2023 Sep.
Article de Anglais | MEDLINE | ID: mdl-37531796

RÉSUMÉ

Brazilian coastal areas have been exposed to various anthropic influences including physical alteration such as marina construction. To assess the impact of the pier marina construction in the Saco da Ribeira cove (Flamengo Bay, SE Brazil), sedimentological (grain size), geochemical (organic and trace elements) parameters and benthic foraminifera were analyzed on a 50-cm-long dated sediment core covering the last century. The multiproxy approach applied to a numerical hydrodynamic model shows that the circulation in the study area underwent an overall reduction (ca. 30 %) after the pier marina construction in the 1970s, promoting an increase of mud accumulation and higher concentrations of total organic carbon and trace elements (i.e., Enrichment Factor Cu from 0.80 to 1.4) as well as a shift in the benthic foraminiferal assemblages (i.e., foraminiferal density from 63 to 23.20 specimens per 10 cm3 and dominance from 0.13 to 0.73). On the basis of these integrated data, better environmental conditions occurred before the 1970s, then an overall increase in environmental stress took place after the pier's marina construction. Our results provide a baseline for future biomonitoring projects in a stressed region and exemplify the strong capability and reliability of benthic foraminifera as bioindicators of paleoenvironmental changes in coastal environments and for understanding how human pressure might induce such changes.


Sujet(s)
Foraminifera , Oligoéléments , Humains , Surveillance de l'environnement/méthodes , Sédiments géologiques , Brésil , Oligoéléments/analyse , Baies (géographie) , Reproductibilité des résultats
5.
Sci Rep ; 13(1): 6728, 2023 04 25.
Article de Anglais | MEDLINE | ID: mdl-37185355

RÉSUMÉ

This study reports a set of primeval marine incursions identified in two drill cores, 1PS-06-CE, and 1PS-10-CE, which recovered the Barbalha Formation, Araripe Basin, Brazil. Based on a multi-proxy approach involving stratigraphy, microbiofacies, ichnofossils, and microfossils, three short-lived marine incursions were identified, designated Araripe Marine Incursions (AMI) 1-3. AMI-1 and AMI-2, which occur within the shales of the Batateira Beds (lower part of the Barbalha Formation), were identified by the occurrence of benthonic foraminifera, calcareous nannofossils, dinocysts, and a mass mortality event of non-marine ostracods. AMI-3 was recognized in the upper part of the Barbalha Formation, based on the occurrence of ichnofossils and planktonic foraminifera. The observation of the planktonic foraminifera genus Leupoldina for the first time in the basin indicates early Aptian/early late Aptian age for these deposits, and the first opportunity of correlation with global foraminifera biozonation. Our findings have implications for the breakup of the Gondwana Supercontinent, as these incursions represent the earliest marine-derived flooding events in the inland basins of northeastern Brazil.


Sujet(s)
Foraminifera , Fossiles , Animaux , Brésil , Crustacea , Plancton
6.
Sci Data ; 10(1): 131, 2023 03 10.
Article de Anglais | MEDLINE | ID: mdl-36899009

RÉSUMÉ

We present the first version of the Ocean Circulation and Carbon Cycling (OC3) working group database, of oxygen and carbon stable isotope ratios from benthic foraminifera in deep ocean sediment cores from the Last Glacial Maximum (LGM, 23-19 ky) to the Holocene (<10 ky) with a particular focus on the early last deglaciation (19-15 ky BP). It includes 287 globally distributed coring sites, with metadata, isotopic and chronostratigraphic information, and age models. A quality check was performed for all data and age models, and sites with at least millennial resolution were preferred. Deep water mass structure as well as differences between the early deglaciation and LGM are captured by the data, even though its coverage is still sparse in many regions. We find high correlations among time series calculated with different age models at sites that allow such analysis. The database provides a useful dynamical approach to map physical and biogeochemical changes of the ocean throughout the last deglaciation.


Sujet(s)
Foraminifera , Eau de mer , Isotopes du carbone/analyse , Carbone , Oxygène
7.
Environ Pollut ; 320: 121003, 2023 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-36623785

RÉSUMÉ

Using benthic foraminifera, we evaluate the ecological quality status (EcoQS) of transitional waters of the Guanabara Bay (SE Brazil) by applying the diversity-based index exp (H'bc) and the sensitivity-based Foram-AMBI for the first time in South America. The Guanabara Bay was selected for this study as it is one of the largest transitional ecosystems in the State of Rio de Janeiro and has been severely impacted by anthropogenic activities. Concentrations of potentially toxic elements (PTEs) were assessed by sequential chemical extraction in three phases (i.e., dissolved in water, adsorbed on organic matter, and Mn oxy-hydroxides). Total organic carbon, total nitrogen, and stable isotope (δ13C and δ15N) signatures of organic matter were analyzed to trace environmental stress. The Ammonia/Elphidium ratio suggests hypoxic conditions at most of the sampled sites. Principal component analysis identifies the first component as environmental stress underlying organic matter and PTE enrichment (in all three phases), which is positively related to Foram-AMBI and negatively to exp (H'bc). The exp (H'bc) and Foram-AMBI indices reveal that stations near the Governador Island and Niterói margin have the worst EcoQS, showing medium to extreme pollution. Additionally, Foram-AMBI and exp (H'bc) provide a congruent EcoQS classification for ∼64% of the sites. Although these results are promising, they suggest that a significant effort should be made to obtain better knowledge of foraminiferal ecological requirements to employ benthic foraminifera as a biomonitoring and management method.


Sujet(s)
Foraminifera , Polluants chimiques de l'eau , Sédiments géologiques/analyse , Écosystème , Baies (géographie) , Brésil , Surveillance de l'environnement/méthodes , Polluants chimiques de l'eau/toxicité , Polluants chimiques de l'eau/analyse
8.
An Acad Bras Cienc ; 94(4): e20200391, 2022.
Article de Anglais | MEDLINE | ID: mdl-36477985

RÉSUMÉ

A foraminiferal faunal study was carried out in a Holocene marine section from Arroyo Baliza, located on the northwest coast of the Beagle Channel, to contribute to the knowledge of the palaeoenvironmental conditions during the marine Holocene event. Foraminiferal assemblage was represented by 32 species distributed among 21 genera. The assemblage was dominated by Elphidium macellum (Fichtel & Moll) Elphidium alvarezianum (d'Orbigny), Cribroelphidium excavatum (Terquem) and Buccella peruviana (d'Orbigny), accompanied by Cibicides fletcheri Galloway & Wissler and Cibicidoides dispars (d'Orbigny) in low proportion. The predominance of Peridiniales dinocysts in the marine palynomorphs assemblage, suggested inner neritic conditions with cooler and more nutrient-rich waters. The distribution of the foraminiferal species was variable throughout the section indicating palaeoenvironmental changes in Arroyo Baliza between 3499-2595 cal yr BP. A gradual passage from high energy, cold and well-oxygenated marine waters towards a shallower environment with low energy and low to moderate salinity of the waters were linked to the regressive phase. This study complements and supports the previous palynological data from this section, which reflects an increase in number and diversity of dinocyst species indicating marine environmental conditions during the late Holocene as it exists today in the Beagle Channel.


Sujet(s)
Foraminifera , Animaux , Chiens , Argentine
9.
São Paulo; s.n; 2022. 1-172 p. graf.
Thèse de Portugais | LILACS, Coleciona SUS, Sec. Est. Saúde SP, CONASS, SESSP-ACVSES, SESSP-TESESESSP, Sec. Est. Saúde SP | ID: biblio-1428785

RÉSUMÉ

Este trabalho teve como objetivo conhecer a produção científica sobre a atividade antifúngica dos compostos químicos gamma-terpineno, terpinene-4-ol e sabineno, de óleos essenciais. Trata-se de um estudo descritivo, exploratório de abordagem quantitativa, realizado por meio de revisão da literatura, onde foi possível mapear a produtividade científica dos compostos bioativos citados. A busca foi realizada em fevereiro de 2021, abordando o período de 1964 a 2020, utilizando a fonte de informação PubMed/MEDLINE. Na pesquisa livre os termos gamma-terpinene and antifungal, terpinene-4-ol and antifungal e sabinene and antifungal e no MeSH Database - Medical Subject Heading Terms (Mesh Terms ­ MeSH) desenvolvido pela U.S National Library of Medicine, utilizando os termos indexados gamma-terpinene and antifungal agents, terpinene-4-ol and antifungal agentes e sabinene and antifungal agents. Foram selecionados e analisados após os critérios de inclusão 192 artigos científicos. A análise foi realizada de forma descritiva com apresentação de frequências absolutas e relativas. O número de citações por artigo foi realizado no Google Acadêmico. Por meio do VOSViewer® foi analisado a rede de colaboração por coautoria e por coocorrência dos termos de pesquisa. A Banaras Hindu University, Universidade Estadual Paulista (UNESP), Universidade Federal do Ceará, Universidade de Coimbra...(AU)


This work aimed to know the scientific production on the antifungal activity of the chemical compounds gamma-terpinene, terpinene-4-ol and sabinene, in essential oils. This is a descriptive, exploratory study with a quantitative approach, carried out through a literature review, where it was possible to map the scientific productivity of the aforementioned bioactive compounds. The search was carried out in February 2021, covering the period from 1964 to 2020, using the information source PubMed/MEDLINE. In the free search the terms gamma-terpinene and antifungal, terpinene-4-ol and antifungal and sabinene and antifungal and in the MeSH Database - Medical Subject Heading Terms (Mesh Terms) developed by the US National Library of Medicine, using the indexed terms gamma -terpinene and antifungal agents, terpinene-4-ol and antifungal agents and sabinene and antifungal agents. 192 scientific articles were selected and analyzed after the inclusion criteria. The analysis was performed descriptively with the presentation of absolute and relative frequencies. The number of citations per article was performed on Google Scholar. Through VOSViewer®, the collaboration network was analyzed by co-authorship and by cooccurrence of the search terms. Banaras Hindu University, State University of São Paulo (UNESP), Federal University of Ceará, University of Coimbra and University of Belgrade, Serbia are the institutions that published the most in the period. Most authors developed the research in public institutions. Iran, India and Brazil were the countries that published the most. The most published journals are located in the United Kingdom and the United States. The most studied family of medicinal plants were Lamiaceae, Apiaceae and Myrtaceae. The most researched medicinal plants in terms of antifungal activity were: Origanum vulgare L. (Oregano), Thymus vulgaris L. (Thyme), Rosmarinus officinalis L. (rosemary), Melaleuca alternifolia L. (Melaleuca), Origanum majorana L. (Marjoram). Candida albicans was the most studied species, followed by Aspergillus niger and Aspergillus flavus. The average life in years of selected articles in PubMed/MEDLINE - free search on gamma-terpinene was 6.5 years; 5-year terpinene-4-ol and 7-year sabinene and in the MeSH Database survey, 7-year gamma-terpinene, 5-year terpinene-4-ol and 8-year sabinene. The analysis of the correlation network by co-authorship and by co-occurrence of the terms used in the research of the selected articles, gamma-terpinene identified three clusters, terpinene-4-ol two clusters and sabinene only one cluster. Based on the analysis of this research with data indexed in the PubMed/MEDLINE information source, it was possible to identify a growth in the studies of chemical compounds isolated from essential oils. (AU


Sujet(s)
Huile essentielle , Composés Chimiques , Activités Scientifiques et Techniques , Foraminifera , Antifongiques
10.
Environ Monit Assess ; 193(7): 458, 2021 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-34213634

RÉSUMÉ

We use benthic foraminifera and hydrography as environmental indicators to characterize the estuarine channel of Bertioga (SP, Brazil). Salinity and temperature measured in four fixed stations (F1-F4) influence differentiation related to species habitat, fluvial discharge, and environmental quality. Tidal oscillation during neap and spring tides changes the Hansen and Rattray stratification-circulation classification from highly stratified (type 2b) to weakly stratified (type 2a). In the northern entrance close to Itapanhaú River, F1 is highly stratified environment (type 2b), with significant difference between bottom and surface salinities, presenting Pararotalia sp., Pseudononion atlanticum, Hanzawaia boueana, and Quinqueloculina lamarckiana as indicator species. F2 in summer is highly stratified (type 2b) with large difference between surface and bottom salinity, whereas in winter is partially mixed weakly stratified (type 2a) with small difference between salinities and the agglutinated Arenoparella mexicana, Haplophragmoides wilberti, and Trochammina inflata thrives. In summer and winter, F3 is partially mixed weakly stratified (type 2a) with A. mexicana, H. wilberti, Trochammina inflata, Ammobaculites sp., and Ammotium salsum. In the southern entrance, F4 in the winter, is partially mixed, weakly stratified system (type 2a) that changes to highly stratified (type 2b) with large difference between salinities. This indicated low influence of fluvial freshwater and high influence of saline and polluted waters from Santos Channel where Arenoparella mexicana, Gaudryina exilis, and Ammotium cassis inhabits. Presence of Quinqueloculina spp. and Triloculina sp. indicates high saline influence, and presence of Ammonia tepida and Elphidium spp. indicates mixohaline environments which salinity dilution occurs.


Sujet(s)
Foraminifera , Brésil , Surveillance de l'environnement , Sédiments géologiques , Eau
11.
Environ Sci Pollut Res Int ; 28(18): 22612-22640, 2021 May.
Article de Anglais | MEDLINE | ID: mdl-33420935

RÉSUMÉ

Multiproxy approach based on textural, mineralogical, geochemical, and microfaunal analyses on a 176-cm-long core (SP8) has been applied to reconstruct the Holocene paleoenvironmental changes and disentangling natural vs. anthropogenic variability in Marambaia Cove of the Sepetiba Bay (SE Brazil). Sepetiba Bay became a lagoonal system due to the evolution and development of the Marambaia barrier island during the Holocene and the presence of an extensive river basin. Elemental concentrations from pre-anthropogenic layers from the nearby SP7 core have been used to estimate the baseline elemental concentrations for this region and to determine metals enrichment factors (EF), pollution load index (PLI), and sediment pollution index (SPI). Record of the core SP8 provides compelling evidence of the lagoon evolution differentiating the effects of potentially toxic elements (PTEs) under natural vs. anthropic forcing in the last ~ 9.5 ka BP. The study area was probably part of coastal sand ridges between ≈ 9.5 and 7.8 ka BP (radiocarbon date). Events of wash over deposited allochthonous material and organic matter between ≈ 8.6 and 7.8 ka. Climatic event 8.2 ka BP, in which the South American Summer Monsoon was intensified in Brazil causing higher rainfall and moisture was scored by an anoxic event. Accumulation of organic matter resulted in oxygen depletion and even anoxia in the sediment activating biogeochemical processes that resulted in the retention of potentially toxic elements (PTEs). After ≈ 7.8 ka BP at the onset of the Holocene sea-level rise, a marine incursion flooded the Marambaia Cove area (previously exposed to subaerial conditions). Environmental conditions became favorable for the colonization of benthic foraminifera. The Foram Stress Index (FSI) and Exp(H'bc) indicate that the environmental conditions turned from bad to more favorable since ≈ 7.8 ka BP, with maximum health reached at ≈ 5 ka BP, during the mid-Holocene relative sea-level highstand. Since then, the sedimentological and ecological proxies suggest that the system evolved to an increasing degree of confinement. Since ≈ 1975 AD, a sharp increase of silting, Cd, Zn, and organic matter also induced by anthropic activities caused major changes in foraminiferal assemblages with a significant increase of Ammonia/Elphidium Index (AEI), EF, and SPI values and decreasing of FSI and Exp(H'bc) (ecological indicators) demonstrating an evolution from "moderately polluted" to "heavily polluted" environment (bad ecological conditions), under variable suboxic conditions. Thus, core SP8 illustrates the most remarkable event of anthropogenic forcing on the geochemistry of the sediments and associated pollution loads and its negative effect on benthic organisms.


Sujet(s)
Foraminifera , Polluants chimiques de l'eau , Baies (géographie) , Brésil , Surveillance de l'environnement , Sédiments géologiques , Polluants chimiques de l'eau/analyse
12.
Zootaxa ; 4821(1): zootaxa.4821.1.7, 2020 Jul 30.
Article de Anglais | MEDLINE | ID: mdl-33056335

RÉSUMÉ

The study about the distribution of benthic foraminifers in relationship with the type of substrate is presented. Samples of surface sediments from 15 to 60 m of depth from the southeast coast of the province of Buenos Aires (40º 30´ - 42ºS), Argentina were analysed. The foraminiferal assemblage was constituted by forty-eight species that belong to 22 genera. It was characterized mostly by the free-living style, epifaunal microhabitats, oxic levels and a detritivore trophic strategy. Based on statistical analysis, three zones were determinated: at 15 m depth , characterized mainly by Buccella peruviana (d´Orbigny), and species of Bolivina reflected a littoral environment with sandy sediments and the most important clay contribution, whereas it also presented the lowest oxygen levels were determinated; between 24-48 m depth, associted by Ammonia parkinsoniana (d´Orbigny), Buccella peruviana and Quinqueloculina seminula (Linné), this zone displayed an oxygenated environment with coarse grainsize from inner shelf where local water circulation may explain the high energy observed; and the last one located between 36 to 58 m of depth was characterized by Buccella peruviana, Ammonia parkinsoniana, Elphidium macellum (Fichtel Moll), Cibicides dispars (d´Orbigny) and Cibicides aknerianus (d´Orbigny) regflecting an inner shelf environment with sandy sediments, the lowest water temperature and the highest oxygen levels.


Sujet(s)
Foraminifera , Animaux , Surveillance de l'environnement , Sédiments géologiques
13.
PLoS One ; 15(10): e0241000, 2020.
Article de Anglais | MEDLINE | ID: mdl-33079958

RÉSUMÉ

Intriguing latest Eocene land-faunal dispersals between South America and the Greater Antilles (northern Caribbean) has inspired the hypothesis of the GAARlandia (Greater Antilles Aves Ridge) land bridge. This landbridge, however, should have crossed the Caribbean oceanic plate, and the geological evolution of its rise and demise, or its geodynamic forcing, remain unknown. Here we present the results of a land-sea survey from the northeast Caribbean plate, combined with chronostratigraphic data, revealing a regional episode of mid to late Eocene, trench-normal, E-W shortening and crustal thickening by ∼25%. This shortening led to a regional late Eocene-early Oligocene hiatus in the sedimentary record revealing the location of an emerged land (the Greater Antilles-Northern Lesser Antilles, or GrANoLA, landmass), consistent with the GAARlandia hypothesis. Subsequent submergence is explained by combined trench-parallel extension and thermal relaxation following a shift of arc magmatism, expressed by a regional early Miocene transgression. We tentatively link the NE Caribbean intra-plate shortening to a well-known absolute and relative North American and Caribbean plate motion change, which may provide focus for the search of the remaining connection between 'GrANoLA' land and South America, through the Aves Ridge or Lesser Antilles island arc. Our study highlights the how regional geodynamic evolution may have driven paleogeographic change that is still reflected in current biology.


Sujet(s)
Phénomènes géologiques , Animaux , Caraïbe , Foraminifera , Porto Rico
14.
Mar Environ Res ; 162: 105121, 2020 Dec.
Article de Anglais | MEDLINE | ID: mdl-32846319

RÉSUMÉ

The Santos Estuary (SE Brazil) is a coastal ecosystem with a high ecological importance and has been strongly impacted by human activities over the last century. A multiproxy analysis of sediment core dated by 137Cs, 210Pb and 226Ra activities and based on sediment geochemistry and benthic foraminifera is here used to reconstruct the environmental changes and the variations of the Palaeo-Ecological Quality Status (Palaeo-EcoQS) during the last ~120 years. The Palaeo-EcoQS was reconstructed by applying the diversity index Exp(H'bc) based on the benthic foraminiferal fauna. Specifically, the Ecological Quality Ratio (EQR) allowed to assess the Palaeo-EcoQS during the last ~120 years using local reference conditions. Based on our data, the pre-industrial period (~1883-1902) represents the reference conditions with "Good" Palaeo-EcoQS. The ~1902-1972 period coincides with the beginning of industrial operations and intensification of coastal urbanization leading to a deterioration of the environmental quality and Palaeo-EcoQS shifting to "Moderate" conditions. Dredging operations in 1972 led to increase the influences of adjacent sea that ultimately resulted in a "Good" Palaeo-EcoQS persisting up to the 1990s. Despite the preservation actions and recovery programs, the 1993-2012 period was characterized by an overall deterioration of the environmental conditions. Indeed, the reconstructed "Poor" to "Bad" Palaeo-EcoQS suggest the ineffectiveness of the remediation actions. This work confirmed that benthic foraminifera are reliable to evaluate EcoQS and Palaeo-EcoQS in estuarine ecosystems. Based on the present findings and previous studies showing the potential of fossil foraminifera to define in situ reference conditions, we recommend the inclusion of foraminifera in the list of biological quality elements within legislations concerning transitional and marine habitats.


Sujet(s)
Foraminifera , Brésil , Écosystème , Surveillance de l'environnement , Estuaires , Sédiments géologiques
15.
An Acad Bras Cienc ; 92(2): e20190486, 2020.
Article de Anglais | MEDLINE | ID: mdl-32813859

RÉSUMÉ

Foraminifera are diversified protists with high ecological and bioindicator importance. Physical-chemical parameters of the environment can be evaluated through the taphonomic analysis of the test coloring, because once they settle in the sediment their tests begin to behave as sedimentary particles. Five urbanized tropical Brazilian beaches were sampled in this study in order to characterize the diversity, abundance, taxonomic and taphonomic structure of Foraminifera assemblages. General environmental characterization such as granulometric analysis, temperature and salinity was also performed. A total of 69 foraminiferan species were found, dominated by Quinqueloculina lamarckiana, Archaias angulatus, Amphistegina lessonii, Ammonia tepida and Eponides repandus. A large predominance of dead tests (>90%) was found, and only them were considered in further analyses. The cluster based on the taxonomic composition formed two groups, separating Miramar from the other beaches. Miramar was dominated by Ammonia tepida (18.9%), Sorites marginalis (16.8%), Quinqueloculina lamarckiana (13.9%) and Textularia agglutinans (10.2%), and had the highest density, number of species and diversity, what may be related with the sheltered nature of this beach and the dominance of fine sand. The other four beaches have high oceanic influence and the medium and coarse sand predominated. In these beaches Quinqueloculina lamarckiana dominated, representing between 30.9 and 38.7% of total foraminiferans. The taphonomic analysis indicates that Miramar presents a high deposition of tests and a low hydrodynamic energy, since the majority of tests were white. In Bessa, Manaíra and Seixas most of the tests were brownish, which is characteristic of beaches with high hydrodynamic energy, which causes the tests to be constantly brought to the oxidation zone.


Sujet(s)
Foraminifera , Plage pour la baignade , Brésil , Biomarqueurs environnementaux , Surveillance de l'environnement , Sédiments géologiques
16.
Mar Pollut Bull ; 158: 111417, 2020 Sep.
Article de Anglais | MEDLINE | ID: mdl-32753201

RÉSUMÉ

Population growth around water bodies is deteriorating environmental quality. The benthic foraminiferal and trace element concentration in a pair of short sediment cores were used to establish the quality of the sedimentary environment in a tropical coastal lagoon in the southwestern Gulf of California. From 25 cm depth towards the surface of the sediment core, Ammonia beccarii was dominant over nontolerant species and the concentrations of V, Ni, Co, Zn, Cu, Hg and Pb in the sediments increased compared with the lower depth intervals. This finding suggests a deterioration in the environmental quality of the lagoon since 1980, associated with an increase in the sizes of the population and vehicle fleet in the city of La Paz, Baja California Sur, and with the operation of three fossil fuel-based thermoelectric plants since 1985.


Sujet(s)
Foraminifera , Oligoéléments/analyse , Polluants chimiques de l'eau/analyse , Californie , Villes , Surveillance de l'environnement , Sédiments géologiques , Mexique
17.
Mar Pollut Bull ; 158: 111449, 2020 Sep.
Article de Anglais | MEDLINE | ID: mdl-32753225

RÉSUMÉ

The ecological quality status of the NE region of the Guanabara Bay (SE Brazil), one of the most important Brazilian embayments, is evaluated. For this purpose, sediment samples from in the inner of the Guanabara Bay (GB) were collected and analyzed (grain-size, mineralogy, geochemistry and living foraminifera). In this study, it is hypothesized that the potentially toxic elements (PTEs) concentrations, in solution and associated with organic matter (OMPTEs, potential nutrient source), may represent two potential pathways to impact benthic foraminifers. A multiproxy approach applied to complex statistical analyses and ecological indexes shows that the study area is, in general, eutrophic (with high organic matter and low oxygen content), polluted by PTEs and oil. As a consequence, foraminifera are not abundant and their assemblages are poorly diversified and dominated by some stress-tolerant species (i.e., Ammonia tepida, Quinqueloculina seminula, Cribroelphidium excavatum). The results allow us to identify a set of species sensitive to eutrophication and OMPTEs. Factors such as the increase of organic matter contents and OMPTEs and, in particular of Zn, Cd and Pb, the oxygen depletion and the presence of oil, altogether contribute to a marked reduction in the abundance and diversity of foraminifera. Ammonia-Elphidium Index and the Foram Stress Index confirm that the NE zone of GB is, in general, "heavily polluted", with "poor ecological quality status" and experiences suboxic to anoxic conditions. In light of it, special attention from public authorities and policymakers is required in order to take immediate actions to enable its environmental recovery.


Sujet(s)
Foraminifera , Baies (géographie) , Brésil , Surveillance de l'environnement , Sédiments géologiques
18.
Environ Sci Pollut Res Int ; 27(12): 13637-13661, 2020 Apr.
Article de Anglais | MEDLINE | ID: mdl-32034594

RÉSUMÉ

Coral communities worldwide are progressively more stressed by anthropogenic activities that increase fluxes of sediment and other pollutants to nearshore areas. Some nearshore coral reef environments off the Equatorial margin of Brazil, including Pirangi and Maracajaú, Rio Grande do Norte (RN, Brazil), seem to be under human-induced stress. However, the horizontal extent of this stress, its effects, and assessment of the environmental response depend on the hydrodynamic conditions (circulation and deposition patterns), sedimentary facies, and the availability of biological indicators. We investigate two Brazilian live reefal corals' communities by examining seven photosymbiont-bearing species (PSB) of Foraminifera, Amphisorus hemprichii, Amphistegina gibbosa, Archaias angulatus, Borelis schlumbergeri, Heterostegina antillarum, Peneroplis carinatus, and Laevipeneroplis proteus, using numerical analysis FORAM Index (FI), grain size, and particulate organic and inorganic carbonate. Here, we show that coarse sand fraction followed by fine sand fraction and high hydrodynamics plays an important role in transportation and deposition of sediments and foraminiferal tests in the study area. According to FI results, conditions at Pirangi are not suitable for coral reef growth. Maracajaú has sites that are suitable for coral reef growth and sites where coral could not survive after a stress event. We need long-term assessments to improve our knowledge of the distribution and ecological importance of Brazilian reef-dwelling foraminifers and to extend the application of FI to monitoring management plans of the Pirangi and Maracajaú National Marine Parks by providing a first insight into the biodiversity patterns and a reliable tool of the reconstruction of paleo reef health.


Sujet(s)
Anthozoa , Foraminifera , Animaux , Brésil , Récifs de corail , Surveillance de l'environnement
19.
Iheringia, Sér. zool ; 110: e2020023, 2020. ilus, tab, map
Article de Anglais | VETINDEX | ID: biblio-1483368

RÉSUMÉ

The geographical distribution of Bathoxiphus ensiculus (Jeffreys, 1877) and Cadulus platensis Henderson, 1920 is greatly extended based on new records, the former being registered for the first time in the southwestern Atlantic. The type materials of both species are figured and an updated diagnosis of Bathoxiphus Pilsbry & Sharp, 1897 is presented. A new deep-sea species of Cadulus is described, Cadulus victori sp. nov., known from only empty shells collected in the Northeast Brazil (off Alagoas and Bahia states) and distinguished from his congeners mainly by the strongly inflated shell, general outline and dimensions. The present study reinforces that although recent taxonomic revisions have been performed on the Scaphopoda from the southwestern Atlantic, there are still unknown or unrecorded species in museum collections, mostly from poorly sampled areas, especially in the deep sea.


Sujet(s)
Animaux , Foraminifera , Mollusca/classification , Mollusca/microbiologie
20.
Iheringia. Sér. Zool. ; 110: e2020023, 2020. ilus, tab, mapas
Article de Anglais | VETINDEX | ID: vti-30677

RÉSUMÉ

The geographical distribution of Bathoxiphus ensiculus (Jeffreys, 1877) and Cadulus platensis Henderson, 1920 is greatly extended based on new records, the former being registered for the first time in the southwestern Atlantic. The type materials of both species are figured and an updated diagnosis of Bathoxiphus Pilsbry & Sharp, 1897 is presented. A new deep-sea species of Cadulus is described, Cadulus victori sp. nov., known from only empty shells collected in the Northeast Brazil (off Alagoas and Bahia states) and distinguished from his congeners mainly by the strongly inflated shell, general outline and dimensions. The present study reinforces that although recent taxonomic revisions have been performed on the Scaphopoda from the southwestern Atlantic, there are still unknown or unrecorded species in museum collections, mostly from poorly sampled areas, especially in the deep sea.(AU)


Sujet(s)
Animaux , Mollusca/classification , Foraminifera , Mollusca/microbiologie
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