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Heterogeneous composition of anthropogenic litter recorded in nests of Yellow-legged gull (Larus michahellis) from a small Mediterranean island Полный текст
2020
Battisti, Corrado
This note reports data about a heterogeneous assemblage of anthropogenic litter recorded in 307 nesting and roosting sites of Yellow-legged Gull (Larus michahellis) from a small Mediterranean island. I obtained items of anthropogenic litter on > 30% on the total, with plastic, glass and paper the significantly more abundant litter categories. Litter items were found in the nests mainly as a dry remnant in the regurgitated pellets. Fragments of expanded polystyrene (EPS) with peck marks were also recorded, these last transported to the nests because of their resemblance to the cuttlebones of the Sepia cuttlefish. Ingestion of this litter and the pecking on EPS can negatively impact on seabirds. Moreover, the presence of this litter highlights a transport of polluting material even at considerable distance from anthropized areas. Finally, the presence of scavenger species (an endemic lizard and terrestrial molluscs) feeding on food remains could suggest an assimilation of litter into the trophic webs.
Показать больше [+] Меньше [-]Recent history of metal contamination in the Fangcheng Bay (Beibu Gulf, South China) utilizing spatially-distributed sediment cores: Responding to local urbanization and industrialization Полный текст
2020
Yu, Xiaoxiao | Zhang, Zhiwei | Feng, Aiping | Gu, Dongqi | Zhang, Rui | Xia, Peng | Yan, Wenwen | Zhou, Xiangjun
In this study, the recent history of heavy metal pollution in the Fangcheng Bay (South China) was reconstructed utilizing three ²¹⁰Pb-dated sediment cores. The metal concentration profiles display three trends since the 1970s and clearly reflect local urbanization and industrialization. The metals in the Fangcheng Bay started to accumulate in the 1970s but remained relatively low until the 1990s which corresponds to the slow urbanization and industrialization. The metal accumulation in the eastern Fangcheng Bay peaked in the early 2000s following the steep increases in accordance with the rapid industrialization of the eastern Fangcheng Bay where the core HSL was collected. Conversely, the heavy metal profiles in the western Fangcheng Bay present slight step increases in the early 2000s followed by a dramatic metal enrichment in the late 2000s; the expansion of these two cores, which begins in the early 2000s, concurs well with the rapid local urbanization and industrialization.
Показать больше [+] Меньше [-]Correlation of the siboglinid (Annelida: Siboglinidae) distribution to higher concentrations of hydrocarbons in the Sea of Okhotsk Полный текст
2020
Karaseva, N. | Gantsevich, M. | Obzhirov, A. | Shakirov, R. | Starovoĭtov, A. | Smirnov, R. | Malakhov, V.
Siboglinids are a characteristic feature of reducing environments. More than 75% of all siboglinids were found in the Sea of Okhotsk at a depth of less than 400 m, while some species are known to inhabit the abyssal depth in other regions. Among the six species of siboglinids encountered in the Sea of Okhotsk, only two are widespread: Siboglinum caulleryi and Oligobrachia dogieli. A significant number of all findings belong to the area where, according to geological data, the methane concentration varies between 0.22 and 4.46*10⁹ nmol/kg. There is a vast territory in the central part of the Sea of Okhotsk that is not inhabited by siboglinids and is characterized by minimum methane concentration values. Thus, data on the Sea of Okhotsk indicate that siboglinids are related to sites of methane seepage.
Показать больше [+] Меньше [-]Seasonal trends in underwater ambient noise near St. Lawrence Island and the Bering Strait Полный текст
2020
Southall, Brandon L. | Southall, Hugh | Antunes, Ricardo | Nichols, Ross | Rouse, Andrew | Stafford, Kathleen M. | Robards, Martin | Rosenbaum, Howard C.
We measured spatial and temporal patterns of ambient noise in dynamic, relatively pristine Arctic marine habitats and evaluate the contributions of environmental and human noise sources. Long-term acoustic recorders were deployed around St. Lawrence Island and the Bering Strait region within key feeding and migratory corridors for protected species that are inherently important to Native Alaskan cultures. Over 3000 h of data from 14 recorders at nine sites were obtained from October 2014 to June 2017. Spatial and temporal ambient noise patterns were quantified with percentile statistics in 1/3rd-octave bands (0.02–8 kHz). Ice presence strongly influenced ambient noise by influencing the physical environment and presence of marine mammals. High variability in noise was observed within and between sites, largely as a function of ice presence and associated factors. Acute contributions of biological and anthropogenic sources to local ambient noise are compared to monthly averages, demonstrating how they influence Arctic soundscapes.
Показать больше [+] Меньше [-]Is Laguncularia racemosa more invasive than Sonneratia apetala in northern Fujian, China in terms of leaf energetic cost? Полный текст
2020
Li, F.L. | Zhong, L. | Cheung, S.G. | Wong, Y.S. | Shin, P.K.S. | Lei, A.P. | Zhou, H.C. | Song, X. | Tam, N.F.Y.
Laguncularia racemosa and Sonneratia apetala are fast-growing exotic mangrove species in Southern China and widely used for afforestation. However, the invasiveness of the two exotic species is still unclear. We compared structural and physiological traits and energy-use related traits between L. racemosa and S. apetala, and with two natives (Kandelia obovata and Aegiceras corniculatum) in northern Fujian. Results showed that leaf construction cost based on mass (CCM) and caloric values of L. racemosa were significantly lower than S. apetala, and the two natives had highest CCM. Because lower CCM, L. racemosa grew faster with a taller height (4.83 m) and wider ground diameter circumference (40.03 cm) than S. apetala (4.43 m tall and 35.63 cm wide) and the two natives (2.42 m tall and 26.78 cm wide). These findings indicated that L. racemosa could be more invasive than S. apetala in mangrove forests in northern Fujian, China where it still grew well, which deserves more attention.
Показать больше [+] Меньше [-]Activity-footprints, pressures-footprints and effects-footprints – Walking the pathway to determining and managing human impacts in the sea Полный текст
2020
Elliott, Michael | Borja, Angel | Cormier, Roland
Determining the overall effects of human activities on the estuaries, seas and coasts, as a precursor to marine management, requires quantifying three aspects. These are: (a) the area in which the human activities take place, (b) the area covered by the pressures generated by the activities on the prevailing habitats and species, in which pressures are defined as the mechanisms of change, and (c) the area over which any adverse effects occur. These features can be respectively termed the activities-footprints, the pressures-footprints and the effects-footprints. The latter in turn incorporates both the effects on the natural system and the effects on ecosystem services from which society extracts goods and benefits. This viewpoint article explains the rationale behind this typology and proposes definitions for each of these three types of footprints.
Показать больше [+] Меньше [-]Evaluating the presence of microplastics in striped dolphins (Stenella coeruleoalba) stranded in the Western Mediterranean Sea Полный текст
2020
Novillo, O. | Raga, J.A. | Tomas, J.
Litter is a well-known problem for marine species; however, we still know little about the extent to which they're affected by microplastics. In this study, we analyse the presence of this type of debris in Western Mediterranean striped dolphins' intestinal contents over three decades. Results indicated that frequency was high, as 90.5% of dolphins contained microplastics. Of these microplastics, 73.6% were fibres, 23.87% were fragments and 2.53% were primary pellets. In spite of the high frequency of occurrence, microplastic amount per dolphin was relatively low and highly variable (mean ± SD = 14.9 ± 22.3; 95% CI: 9.58–23.4). Through FT-IR spectrometry, we found that polyacrylamide, typically found in synthetic clothes, was the most common plastic polymer. Here, we establish a starting point for further research on how microplastics affect this species' health and discuss the use of striped dolphins as indicators of microplastics at sea.
Показать больше [+] Меньше [-]Chemical composition of microplastic in sediments and protected detritivores from different marine habitats (Salina Island) Полный текст
2020
Renzi, Monia | Blašković, Andrea | Broccoli, Andrea | Bernardi, Giulia | Grazioli, Eleonora | Russo, Giovanni
This study estimates chemical composition of microplastic in sediments and benthic detritivores (sea cucumbers) collected from different marine rocky bottom habitat types (bank, landslide, cliff) of Salina Island (Aeolian Archipelago, Italy). Also, species richness and bottom coverings by benthic species were recorded at each sampling station. Correlations among chemical composition of microplastic in sediments and in detritivores were explored linking recorded variability to the factor “habitat type”. Results evidence that the habitat types considered in this study are characterized by wide species richness and by high percentages of bottom coverage by protected species by international conventions. In spite of the high ecological value of habitats considered in this study, microplastics were recorded both in sediments (PVC, PET, PE, PS, PA, PP) and in stomach contents of sea cucumbers (PET, PA) collected in all sampling sites, confirming the exposure of benthic species to microplastic pollution.
Показать больше [+] Меньше [-]Seasonal variation of oxidative biomarkers in gills and digestive glands of the clam Anomalocardia flexuosa and the mangrove oyster Crassostrea rhizophorae Полный текст
2020
Sardi, Adriana E. | Sandrini-Neto, Leonardo | Lana, Paulo da Cunha | Camus, Lionel
We determined values of antioxidant biomarkers catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione S-transferase (GST) and malondialdehyde (MDA) in two bivalve species from a subtropical system in Brazil. Differences in the biomarkers activities measured in digestive glands and gills sampled at two seasons and in sites with different levels of contamination were tested using univariate and multivariate analyses. Seasonality was the main factor accounting for overall variability. Significant SOD and GPx activities and increased levels of lipid peroxides were detected in summer, while CAT activity was higher in winter. However, biomarkers respond to complex environmental settings as indicated by the significant interaction between season and contamination level. We propose A. flexuosa as a candidate for monitoring studies with sampling occurring at a yearly timescale, and using C. rhizophorae is better suited for designs that include both seasons.
Показать больше [+] Меньше [-]Occurrence, distribution, and risk assessment of bisphenol A in the surface sediments of Musa estuary and its tributaries in the northern end of the Persian Gulf, Iran Полный текст
2020
Safakhah, Narges | Ghanemi, Kamal | Nikpour, Yadollah | Batvandi, Ziba
Musa estuary and its tributaries, located northwest of the Persian Gulf, host many industrial complexes, high-density ports, and urban areas along their coastal regions and are, therefore, constantly threatened by chemical contamination. The present study is the first to have investigated the surface sediments in six stations of the Musa estuary tributaries. The mean variations in BPA concentrations in the dry sediments of these stations ranged from 2.22 to 16.71 ng/g. Fairly high levels of BPA were found in Durragh station and its neighboring industrial sites. The lowest BPA level (2.22 ng/g) was observed in the station at the mouth of the Persian Gulf. Based on the EU risk-assessment system, the concentration levels of BPA in the sediments are in the low-risk range. Only in certain areas of the estuary were the sediments of moderate risk, and prolonged contact between ecological populations and them could cause toxicity in aquatic organisms.
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