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1.
Data Brief ; 50: 109603, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37823064

RESUMO

We present an image dataset of monothalamous soft-shelled Foraminifera (Monothalamea, [1]), an important component of benthic foraminiferal assemblage in sediment cores collected during two oceanographic expeditions that contributed to the MSM30-CORIBAR project (Ice dynamics and meltwater deposits: coring in the Kveithola trough, NW Barents Sea). 9 subsamples of sediment cores were collected during different years (2013-2016) in the Kveithola Trough, a glacially carved system in the NW Barents Sea. Cores were retrieved using a multi-corer (MUC) and a giant box-corer (GBC) and the subcores for foraminiferal analyses were obtained using Plexiglas tubes inserted manually into the cores. These subcores were sliced at 0.5 cm intervals down to 2 cm sediment depth and then every 1 cm down to 10 cm. Two staining methods, Cell Tracker Green (CTG) and Rose Bengal (RB), were used to distinguish between living and dead individuals. Then, the fixed sediment samples were sieved through 63 and 150 µm mesh screens and preserved in 10 % borax-buffered formalin. Six species and 37 undescribed morphotypes were recognized and included in this image dataset. Relatively few species of soft-shelled, monothalamous foraminifera have been described compared to a much larger number of undescribed morphotypes recognised from across the marine realm. Few researchers study with their taxonomy because of the time and difficulties that morphological identification involves. In addition, because "soft", delicate monothalamids rarely fossilize, they are generally overlooked by micropaleontologists. However, they are abundant and diverse and represent an important faunal component of marine as well as freshwater ecosystems. Further information about these frequently overlooked protists will help to address important knowledge gaps and enhance our ability to manage and conserve the planet's resources responsibly. In particular, our image dataset highlights the importance of monothalamous soft-shelled foraminifera in this peculiar Arctic environment and contributes to the first species/morphotype checklist for the area. We hope it will serve to fill gaps in knowledge regarding the ecology and biodiversity of benthic foraminifera, helping users to identify monothalamids species and morphotypes in Arctic waters and beyond. This data article is associated with the research papers: "Benthic foraminiferal assemblages and environmental drivers along the Kveithola Trough (NW Barents Sea)" by [2].

2.
Dis Aquat Organ ; 143: 159-168, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632994

RESUMO

We investigated the cause of skeletal deformities found in brown trout from the Aspromonte mountain area in Reggio Calabria, Italy. Toxicological, histopathological and parasitological analyses were carried out on 14 fish with evident macro-morphological alterations from 2 different locations in the same river, and 4 control fish without morphological alterations from a different river (far from the first river but still within the area under study). Histopathological and radiological observations confirmed severe skeletal deformities in the specimens investigated. Parasitological examinations highlighted the presence of the nematode Cystidicoloides ephemeridarum, found only within the gastrointestinal tract of specimens showing deformities. Moreover, a direct correlation between parasite number and fish size was found. Given the low heavy metal levels and the presence of a massive parasitosis in teleosts showing deformities, we postulate a correlation between skeletal deformities and nematode infestation: the parasites caused a serious vitamin and mineral deficiency in the fish, which led to a dysplastic vertebral column. The low calcium levels found in malformed specimens compared with negative controls effectively confirm this hypothesis.


Assuntos
Doenças dos Peixes , Animais , Itália , Truta
3.
Artigo em Inglês | MEDLINE | ID: mdl-33207370

RESUMO

Crystalline rocks can produce dangerous radiation levels on the basis of their content in radioisotopes. Here, we report radiological data from 10 metamorphic and igneous rock samples collected from the crystalline basement of the Peloritani Mountains (southern Italy). In order to evaluate the radiological properties of these rocks, the gamma radiation and the radon emanation have been measured. Moreover, since some of these rocks are employed as building materials, we assess the potential hazard for population connected to their use. Gamma spectroscopy was used to measure the 226Ra, 232Th and 40K activity concentration, whereas the radon emanation was investigated by using a RAD 7 detector. The results show 226Ra, 232Th and 40K activity concentration values ranging from (17 ± 4) to (56 ± 8) Bq kg-1, (14 ± 3) to (77 ± 14) Bq kg-1 and (167 ± 84) to (1760 ± 242) Bq kg-1, respectively. Values of the annual effective dose equivalent outdoor range from 0.035 to 0.152 mSv y-1, whereas the gamma index is in the range of 0.22-0.98. The 222Rn emanation coefficient and the 222Rn surface exhalation rate vary from (0.63 ± 0.3) to (8.27 ± 1.6)% and from (0.12 ± 0.03) to (2.75 ± 0.17) Bq m-2 h-1, respectively. The indoor radon derived from the building use of these rocks induces an approximate contribution to the annual effective dose ranging from 8 to 176 µSv y-1. All the obtained results suggest that the crystalline rocks from the Peloritani Mountains are not harmful for the residential population, even though they induce annual effective doses due to terrestrial gamma radiation above the worldwide average values. Moreover, their use as building materials does not produce significant health hazards connected to the indoor radon exposure.

4.
Mar Environ Res ; 131: 195-204, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28992961

RESUMO

The ability to observe and predict trawling-induced patterns at spatial and temporal scales that are relevant to inform realistic management strategies is a challenge which scientists have consistently faced in recent decades. Here, we use fish feeding behaviour, a biological trait easily impaired by trawling disturbance, to depict alterations in fish condition (i.e. individual fitness) and feeding opportunities. The benthivorous fish Mullus barbatus barbatus was selected as a model species. The observed trends of responses to trawling in prey species confirmed the effectiveness of a non-trawled zone in sustaining higher levels of diet diversity (e.g. quantity and quality of ingested prey) and fish condition values (e.g. morphometric and physiological Condition Index). Changes observed in fish prey selection confirmed the role of trawling disturbance in modifying the local soft bottoms community, producing alterations of prey availability that trigger shifts in fish diet. Trawling-induced feeding patterns, mirrored through stomach contents, can positively or negatively affect fish condition, the main driver of population dynamics in maintaining carrying capacity levels. Due to the widespread socio-economic value of the red mullet fishery, and the current exploitation status, evidence gathered by the proposed bottom-up trait based approach might inform future trawling adaptation strategies, and tailor spatial conservation measures supporting an Ecosystem-Based Fisheries Management.


Assuntos
Comportamento Alimentar , Pesqueiros/estatística & dados numéricos , Peixes/fisiologia , Animais , Ecossistema , Monitoramento Ambiental , Perciformes , Dinâmica Populacional
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