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Growth, condition and metal concentration in juveniles of two Diplodus species in ports
2018
Bouchoucha, Marc | Brach-papa, Christophe | Gonzalez, Jean-louis | Lenfant, P. | Darnaude, A. M.
High abundances of juvenile fish in certain ports suggest they might provide alternative nursery habitats for several species. To further investigate this possibility, post-settlement growth, metal uptake and body condition were estimated in 127 juveniles of two seabream species, collected in 2014–15, inside and outside the highly polluted ports of the Bay of Toulon. This showed that differences in local pollution levels (here in Hg, Cu, Pb and Zn) are not consistently mirrored within fish flesh. Muscle metal concentrations, below sanitary thresholds for both species, were higher in ports for Cu, Pb and V only. Otherwise, fish muscle composition principally differed by species or by year. Juvenile growth and condition were equivalent at all sites. Higher prey abundance in certain ports might therefore compensate the deleterious effects of pollution, resulting in similar sizes and body conditions for departing juvenile fish than in nearby natural habitats.
اظهر المزيد [+] اقل [-]Distribution of micropollutants in estuarine and sea water along the Portuguese coast
2020
Sousa, João C.G. | Barbosa, Marta O. | Ribeiro, Ana R.L. | Ratola, Nuno | Pereira, Manuel F.R. | Silva, Adrián M.T.
This work provides the first spatial distribution report of micropollutants (MPs) in the entire Portuguese coast, comprising the ocean shore (sea water, SW) and whenever possible the nearest river discharging on it (estuarine water, EW). This surface water monitoring programme aimed to assess the spatial distribution of 37 MPs with a wide chemical nature, including some substances prioritized by the European Union Directive 39/2013/EU and contaminants of emerging concern targeted in the Watch List of Decisions 495/2015/EU and 840/2018/EU. The risk quotients were estimated in each sampling point for the detected MPs. High concentrations of diclofenac, tramadol and carbamazepine were determined, the latter with medium to high risk for algae. Some pharmaceuticals and perfluorooctanesulfonic acid (PFOS) were broadly distributed, maybe due to the direct discharge into the sea. Atrazine and alachlor were found in the majority of the samples, with alachlor levels often considered as medium to high risk.
اظهر المزيد [+] اقل [-]Bioavailability and assessment of heavy metal pollution in sediment cores off the Mejerda River Delta (Gulf of Tunis): How useful is a multiproxy approach?
2016
Helali, Mohamed Amine | Oueslati, Walid | Zaaboub, Noureddine | Added, Ayed | Aleya, Lotfi
Three core samples were taken from zones offshore from the Mejerda River Delta (Tunisia) and analyzed for major and trace elements to assess their relationships with organic matter, monosulfides and carbonates, as well as for pollution and bioavailability. Chemical speciation, ∑ SEM/AVS, the enrichment factor (EF) and the geo-accumulation index (I-geo) were used. Iron, cadmium, lead and zinc – the most frequently mined metals in the Mejerda catchment – were found as contaminants in the offshore areas. Estimations of trace element accumulation using the EF and the I-geo index show that lead, and to a lesser extent zinc, are the most polluting metals off the Mejerda outlet. According to their bioavailability, these metals are also the most toxic. Only cadmium is heavily present in delta sediment (EF>100) though deeply sequestrated (100% bound to the residual fraction) and thus presents no toxicity.
اظهر المزيد [+] اقل [-]Sedimentary PBDEs in urban areas of tropical Asian countries
2013
Kwan, Charita S. | Takada, Hideshige | Mizukawa, Kaoruko | Saha, Mahua | Rinawati, | Santiago, Evangeline C.
Polybrominated diphenyl ethers (PBDEs) were measured in surface sediment samples collected from urban canals or rivers in Lao PDR, Cambodia, Vietnam, India, Indonesia, Thailand, the Philippines, Malaysia and Japan. The total PBDE concentrations in the sediments ranged from 0.83 to 3140ng/g dry wt. BDE-209 was predominant, ranging from 43% to 97% of total PBDEs, followed by nona-BDEs and some detectable concentrations of BDEs 47, 49, 99, 100, 153, 154 and 183. Sedimentary PBDE levels in Malaysia, Cambodia, the Philippines and Thailand were generally higher than those reported for highly industrialized countries. Spatial distribution of PBDEs indicated that inland sources may impact coastal areas. The presence of BDE congeners which are not contained in technical mixtures and the higher proportions of nona-BDEs relative to BDE-209 in the sediments were identified as indicators of debromination. BDE-209 was possibly debrominated under anaerobic conditions in some of the sediment samples.
اظهر المزيد [+] اقل [-]Boat-induced pressure does not influence breeding site selection of a vulnerable fish species in a highly anthropized coastal area
2022
Picciulin, Marta | Zucchetta, Matteo | Facca, Chiara | Malavasi, Stefano
The brown meagre (Sciaena umbra) is a vulnerable vocal fish species that may be affected by boat noise. The breeding site distribution along the anthropized Venice sea inlets was investigated, by using the species' chorusing activity as a proxy of spawning. Passive acoustic campaigns were repeated at 40 listening points distributed within the three inlets during three-time windows in both summer 2019 and 2020. The role of temporal, morphological, and hydrodynamic variables explaining the observed distribution patterns was evaluated using a GLM approach, considering also human-induced pressures among the candidate predictors. The GLM analysis indicates a higher probability of recording S. umbra chorus after sunset in deeper areas of the inlets, characterized by low water current, while the underwater noise overlapping the species' hearing range and boat abundance did not play any role. This suggests that the species' breeding site choice in the inlets was not influences by boat-induced pressure.
اظهر المزيد [+] اقل [-]Growth, condition and metal concentration in juveniles of two Diplodus species in ports
2018
Bouchoucha, M. | Brach-Papa, C. | Gonzalez, J.-L. | Lenfant, P. | Darnaude, A.M.
High abundances of juvenile fish in certain ports suggest they might provide alternative nursery habitats for several species. To further investigate this possibility, post-settlement growth, metal uptake and body condition were estimated in 127 juveniles of two seabream species, collected in 2014–15, inside and outside the highly polluted ports of the Bay of Toulon. This showed that differences in local pollution levels (here in Hg, Cu, Pb and Zn) are not consistently mirrored within fish flesh. Muscle metal concentrations, below sanitary thresholds for both species, were higher in ports for Cu, Pb and V only. Otherwise, fish muscle composition principally differed by species or by year. Juvenile growth and condition were equivalent at all sites. Higher prey abundance in certain ports might therefore compensate the deleterious effects of pollution, resulting in similar sizes and body conditions for departing juvenile fish than in nearby natural habitats.
اظهر المزيد [+] اقل [-]Assessing the sewage discharge effects on soft-bottom macrofauna through traits-based approach
2021
Vesal, Seyed Ehsan | Nasi, Federica | Pazzaglia, Jessica | Ferrante, Larissa | Auriemma, Rocco | Relitti, Federica | Bazzaro, Matteo | Del Negro, Paola
We assessed the effect of sewage-derived materials on the structural and functional attributes of the soft-bottom macrofauna at an increasing distance from the entire diffusion area. Our results showed clear spatial changes of macrofaunal density and biomass along the distance gradient from the main outfall. High values of biodiversity, species composition, and species linked to organic enrichment near the duct suggested that moderate organic stress affected this community. The traits analysis abundance-based, compared to biomass-based one, distinguished most clearly sewage contamination conditions. Functional diversity displayed spatial patterns with higher values in the less impacted sites and was significantly related to species numbers and the biotic indices (like M-AMBI). This approach is ideal for detecting macrofaunal functional changes due to sewage contamination. Thus, we infer that traits analyses could offer great potential for environmental assessment and monitoring of coastal areas influenced by human activities.
اظهر المزيد [+] اقل [-]Occurrence of perfluoroalkyl substances (PFASs) in marine plastic litter from coastal areas of Central Chile
2021
Gomez, Victoria | Torres, Mariett | Karásková, Pavlina | Přibylová, Petra | Klánová, Jana | Pozo, Karla
Perfluorinated alkyl substances (PFASs) were determined in marine plastic litter (MPL) on six beaches of central Chile. MPL was characterized physically and chemically, showing an abundance of macroplastic (size >2.5 cm). The polypropylene (PP) (47%) was the predominant polymer found. The Desembocadura beach, located at the mouth of the Biobio River, recorded the highest abundance of MPL (3.7 items m⁻²). PFAS detected (n = 15/21) ranged from 279 to 1211 pg g⁻¹ and accounted for MeFOSE (46%) > PFHxS (14%) > PFPA (11%) > PFBS (6%) > PFOA (4%) and > PFOS (4%). Long-chain PFAS were prevalent, which can be metabolically degraded into PFOS (new POPs). This study i) highlights the need to further investigate the occurrence of chemicals in the MPL to reduce their impact on the environment; and ii) points out the need to improve future coastal management strategies for the elimination of solid waste along the coast of the country.
اظهر المزيد [+] اقل [-]The role of mangroves in supporting ports and the shipping industry to reduce emissions and water pollution
2022
Pham, H.T. | Ngô, V.T. | Pham Thu Thuy | Bùi, T.T. | Nguyễn Thị, L.G.
This report provides scientific evidence on the role of mangroves in absorbing greenhouse gases and improving water quality through analysis of monitoring data relating to the water environment in Saigon River (Ho Chi Minh City), greenhouse gas emissions from Ho Chi Minh City seaports, and greenhouse gas sequestration in Can Gio mangrove forest (Ho Chi Minh City). This document presents, for the first time, comparative results of water quality indices for 2010–2020, at monitoring points in different areas including metropolitan, seaport, mangrove forest and open coast. A correlation between carbon emissions from seaports, and the amount of carbon absorbed by mangroves in Ho Chi Minh City, was also analysed for the first time. Our findings confirmed that mangroves can support the maritime industry to reduce greenhouse gas emissions and protect the environment. These findings can assist policymakers to identify those who can financially contribute towards the environmental services that mangroves provide, enabling the effective implementation of policy around payment for forest environmental services. We also highlight the need to have further specific studies, in other areas of the country, in order to build a complete database of the ecosystem services provided by mangroves in Vietnam.
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