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Exposure to pet-made microplastics: Particle size and pH effects on biomolecular responses in mussels 全文
2020
Provenza, Francesca | Piccardo, Manuela | Terlizzi, Antonio | Renzi, Monia
This study aims to evaluate the expression of biomarkers of oxidative stress (LPO, GPx, AtCh, SOD) in mussels (Mytilus galloprovincialis) following the exposure to suspensions of microparticles irregular shaped fibres of Polyethylene terephthalate of different sizes (small 5–60 μm, S-PET; medium 61–499 μm, M-PET; large 500–3000 μm, L-PET) at a single dose of 0.1 g/L. Mussels were tested under two different starting pH conditions of marine water: standard (8.0) and acidified (7.5). The results obtained from this study show that: i) PET microplastics are able to induce biochemical stress in mussels; ii) among the biomarkers tested, LPO and GPx were more effective in detecting the stress induced by microplastic in both initial pH conditions; iii) the expression of biomarkers was influenced by the size of the microparticle. In particular, greater effects were associated with the largest PET particle tested (0.5–3.0 mm); iv) regarding the effect of pH, in experiments starting from 7.5 pH the animals showed a lower biomarker expression than those starting from 8.0 pH.
显示更多 [+] 显示较少 [-]Bacterial community and environmental factors associated to rivers runoff and their possible impacts on coral reef conservation 全文
2020
Paulino, Gustavo Vasconcelos Bastos | Félix, Ciro Ramon | Silvan, Cinta Gomez | Andersen, Gary L. | Landell, Melissa Fontes
Rivers potentially conduct important components as result of anthropogenic stressors for coral reefs. Molecular techniques are increasingly being used for monitoring biological and chemical monitoring of rivers and reefs. Here, we use PhyloChips™ to process surface water samples collected along two rivers and associated reefs in an environmental protection area in northeastern Brazil. Our results indicate that a significant part of Operational Taxonomic Units (OTUs) identified were able to survive the transition from freshwater to seawater, several of them belonging to genera implicated in human pathogenesis. The BBC:A ratio and functional prediction suggests that both study rivers are subject to fecal contamination and xenobiotics input and that the bacterial communities were more homogeneous in these environments. We suggest that protection actions adopted for reefs should be broadly extended to the surrounding environment, and that other bacterial group (besides cultivable coliforms) should be included in routine water quality monitoring.
显示更多 [+] 显示较少 [-]Identifying recent sources and fate of sedimentary nitrogen in the Baltic Sea based on organic matter elemental composition and nitrogen and carbon stable isotopes ratios 全文
2020
Winogradow, Aleksandra | Pempkowiak, Janusz
Sedimentary nitrogen (SN) provenience and fate in surface and subsurface sediments collected from the Baltic Sea were assessed. SN and sedimentary organic carbon (SOC) concentrations, stable isotopic signatures (δ¹⁵NSN and δ¹³CSOC) and SOC/SN molar ratios, were determined in subsequent layers of twenty-four sediment cores dated with ²¹⁰Pb/¹³⁷Cs and fifty-seven surface sediments. Sedimentation rates in the range 66–736 g/m²yr⁻¹ (0.05–0.34 cm/year) were measured. Prolonged incubation of sediments in the laboratory led to a 17–37% decrease of SN in surface sediments, and no SN loss in sediments deposited before 1940. Decrease of δ¹⁵NSN on incubation (1‰ on average), and gradients of δ¹⁵NSN, between recent - surface (3.5‰) vs. 100 years old - subsurface (2.1‰) sediments were attributed to varying contributions of labile nitrogen to the SN pool. Annual deposition of SN to sediment surface and burial in subsurface sediments amounted, respectively, to 5 ± 2 g/m² and 3.5 ± 1 g/m².
显示更多 [+] 显示较少 [-]Evaluation of polypropylene plastic degradation and microplastic identification in sediments at Tambak Lorok coastal area, Semarang, Indonesia 全文
2020
Khoironi, Adian | Hadiyanto, Hadiyanto | Anggoro, Sutrisno | Sudarno, Sudarno
This study aims to determine the degradation of plastic polypropylene (PP) and identify the presence of microplastic in sediments and seawater along the Tambak Lorok coastal area. The study was conducted by collecting samples from the sea surface area, at 50 cm and 170 cm depths, while seawater and sediments were collected from six stations. The results showed an early stage of degradation because of abiotic factors. The surface morphology of plastic changed, indicating the disorientation of the plastic. Furthermore, the results demonstrated that organic carbon decreased by 3.15%, 6.67%, and 16.76% for the PP applied on surface water, at 50 cm depth and at 170 cm depth, respectively. From six stations, PP microplastic was the dominant type, where microplastic in sediment was bio-fouled fiber ranging in size from 255.23 to 1245.71 μm; however, in seawater, it was 7–111 particles/10 mL and ranged from 270.27 to 1279.12 μm in size.
显示更多 [+] 显示较少 [-]Transfer dynamics of macroplastics in estuaries – New insights from the Seine estuary: Part 2. Short-term dynamics based on GPS-trackers 全文
2020
Tramoy, R. | Gasperi, J. | Colasse, L. | Silvestre, M. | Dubois, P. | Noûs, C. | Tassin, B.
Transfer dynamics of macroplastics in estuaries – New insights from the Seine estuary: Part 2. Short-term dynamics based on GPS-trackers 全文
2020
Tramoy, R. | Gasperi, J. | Colasse, L. | Silvestre, M. | Dubois, P. | Noûs, C. | Tassin, B.
The dynamics of plastic debris were assessed in the Seine River, especially in the estuary, using plastic bottles equipped with GPS-trackers. In one year, 50 trajectories were recorded, covering a wide range of hydrometeorological conditions. Results show a succession of stranding/remobilization episodes in combination with alternating upstream and downstream transport in the estuary. In the end, 100% of the tracked bottles stranded somewhere, for hours or weeks, from one to several times at different sites. The overall picture shows that different physical phenomena interact with various time scales ranging from hours/days (high/low tides) to weeks/months (spring/neap tides and highest tides) and years (seasonal river flow). Thus, the fate of plastic debris is highly unpredictable, but the consequence of those interactions is that the transfer of debris is chaotic and not straightforward, and its residence time is much longer than the transit time of water.
显示更多 [+] 显示较少 [-]Transfer dynamics of macroplastics in estuaries – New insights from the Seine estuary: Part 2. Short-term dynamics based on GPS-trackers 全文
2020
Tramoy, R. | Gasperi, J. | Colasse, L. | Silvestre, M. | Dubois, P. | Noûs, Camille | Tassin, B. | Laboratoire Eau Environnement et Systèmes Urbains (LEESU) ; École nationale des ponts et chaussées (ENPC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12) | Eau et Environnement (GERS-LEE) ; Université Gustave Eiffel | SOS Mal de Seine | Centre National de la Recherche Scientifique (CNRS) | Fédération Île-de-France de Recherche sur l'Environnement (FIRE) ; Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-AgroParisTech-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Institute of Microtechnology ; Université de Neuchâtel = University of Neuchatel (UNINE)
International audience
显示更多 [+] 显示较少 [-]Transfer dynamics of macroplastics in estuaries – New insights from the Seine estuary: Part 2. Short-term dynamics based on GPS-trackers 全文
2020
Tramoy, R. | Gasperi, J. | Colasse, L. | Silvestre, M. | Dubois, P. | Noûs, Camille | Tassin, B.
Biodegradation of MC252 polycyclic aromatic hydrocarbons and alkanes in two coastal wetlands 全文
2020
Rodrigue, Matthew | Elango, Vijaikrishnah | Curtis, David | Collins, Autumn W. | Pardue, John H.
Complementary microbial and geochemical assessment techniques investigated the biodegradation of PAHs and alkanes in salt marshes impacted by crude oil following the Macondo spill. Contamination was observed in the top 10 cm of the marsh profile based on PAH analysis and measurement of the δ¹³C signature of impacted marsh soils. Measurement of evolution of ¹³C depleted CO₂ indicated mineralization of crude oil ranging from 2.7–12.1 mg CO₂-C/m²-hr. Changes in weathering ratios of alkylated phenanthrenes and dibenzothiophenes indicated loss of these 3-ring PAHs consistent with biodegradation. A diverse microbial population was observed at both locations dominated by Gammaproteobacteria and including known hydrocarbon degraders such as Marinobacter and Alcanivorax. There was shared richness between sites and across seasons but results suggested substantial turnover of phylotypes in space and time. Biodegradation of alkanes and alkylated PAHs occurred when oxygen was provided in laboratory reactors but not in the absence of oxygen.
显示更多 [+] 显示较少 [-]Trace metal contamination in the marine sediments off Point Calimere, Southeast coast of India 全文
2020
Gopal, V. | Krishnamurthy, R.R. | Kiran, D.R Sakthi | Magesh, N.S. | Jayaprakash, M.
Twenty-five offshore sediment samples were collected after the Gaja cyclone to evaluate the sediment quality in terms of its metal concentration. The samples were examined for organic matter, textural characteristics, calcium carbonate, and trace metals (Fe, Mn, Ni, Co, Cu, and Cr). The geo-accumulation index, enrichment factor, contamination factor, and pollution load index revealed that the study area was highly contaminated with Cu, Zn, and Co. Reasonable to extensive contamination was observed for Fe, Cr, and Ni, whereas Mn was under the uncontaminated category. Statistical analyses revealed that the contamination of Cu, Zn, and Ni are mainly originated from human activities such as boat navigation, fuel combustion, and tourism. Cyclones such as Gaja cause ecological disturbances of the terrestrial and transitional environments and also increase the level of offshore contamination by flooding the contaminated coastal landforms and transporting the contaminants to the sea.
显示更多 [+] 显示较少 [-]Assessment of heavy metal contamination at Tallaboa Bay (Puerto Rico) by marine sponges' bioaccumulation and fungal community composition 全文
2020
Rosado Rodríguez, Gualberto | Otero Morales, Ernesto
The water filtering capacity, and the potential to accumulate contaminants such as heavy metals, make marine sponges suitable candidates for biomonitoring of marine ecosystems. Sponges also harbor a variety of endosymbionts, including fungi, which could be affected by the accumulation of contaminants. This work examined the bioaccumulation factors of heavy metals by sponges from coastal waters from Puerto Rico. Fungal communities associated with marine sponges were assessed to determine if their composition co-varied with heavy metals in sponge tissue. All sponges in our study where found to bioaccumulate arsenic, cadmium and copper. Fungi associated with the sponges showed variations in community composition among localities and sponge species. Our results suggest that sponges, specially Tedania ignis, could be used as a complementary component for biomonitoring of arsenic, cadmium and copper; and that members of the harbored fungal communities could be negatively affected by the accumulation of heavy metals in the sponges.
显示更多 [+] 显示较少 [-]Modern modes of sediment distribution and the anthropogenic heavy metal pollution record in northeastern Beibu Gulf, south China sea 全文
2020
Wang, Rong | Xu, Dong | Ge, Qian
During the expedition 908 survey in 2007, 539 seafloor surface sediment samples and two cores were collected over a narrow sector of the northeastern Beibu Gulf, South China Sea. Currently, three dynamic sedimentological processes prevail in the study area: circulation-controlled sand deposition, mud deposition under weak sediment dynamics, and fluvial input. Core A233 from the circulation-controlled sand area, with a 60 cm mixed layer, provides evidence of dynamics disturbance since the mid-Holocene. To reconstruct the anthropogenic heavy metal pollution history, we selected core A146 from the stable mud sector influenced by fluvial input. The dating of core A146 was based on ²¹⁰Pb activity analysis, showing an ~90-year historical record in the upper 40 cm. The heavy metal contamination results showed a generally low pollution level. Nonetheless, increased pollution has happened since the 1950s, especially after 1978 A.D., corresponding to the beginning of China's reform and opening up.
显示更多 [+] 显示较少 [-]Microplastics and accumulated heavy metals in restored mangrove wetland surface sediments at Jinjiang Estuary (Fujian, China) 全文
2020
Deng, Jun | Guo, Peiyong | Zhang, Xiaoyan | Su, Haitao | Zhang, Yuxuan | Wu, Yanmei | Li, Yanqi
Microplastics have received widespread attention as an emerging contaminant, but limited information was available during wetland restoration. The occurrence and characteristics of microplastics and their interaction with heavy metals in surface sediments from the Jinjiang Estuarine restored mangrove wetland were investigated. The abundance of microplastics ranged from 490 ± 127.3 to 1170 ± 99.0 items/500 g dry sediment, and the restored regions were much higher than mudflats, indicating mangrove restoration promoted its accumulation. Polyethylene terephthalate (PET), polyethylene (PE) and polypropylene (PP) were the main materials of microplastics after Raman spectroscopy identification. SEM-EDS images illustrated the mechanical erosion and chemical weathering on microplastics' surface, and Cr, Zn, Pb, and Cd were observed in elemental composition. The contents of Cr, Ni, Cu, Zn, Pb, As, and Cd accumulated in microplastics were not correlated with their total concentrations in sediments except for Hg, indicating that they might not be derived from sediments.
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