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Using beached bird data to assess seabird oiling susceptibility Texto completo
2022
Waugh, Jazzmine K. | Jones, Timothy | Parrish, Julia K.
Oil spills can cause severe impacts on seabirds, the extent of which varies by species. We investigated taxon-specific susceptibility using data from the Nestucca and Tenyo Maru oil spills in the northeast Pacific together with seasonally and spatially overlapping baseline beached bird abundance data collected over a 17-year time-period. Multivariate analyses revealed patterns of variation between spill and non-spill data, primarily driven by differences in the relative abundance of common murres (Uria aalge) and northern fulmars (Fulmarus glacialis). In subsequent susceptibility analyses, alcid (Alcidae spp.) carcasses were generally overrepresented in spill data, while gulls (Larus spp.), tubenoses (Procellariformes spp.), and cormorants (Phalacrocoracidae spp.) were generally under-represented. We found that the baseline data had high variability, suggesting a need for many years of baseline data. We propose that where appropriate baseline data exists, this method can be employed to investigate the seabirds most vulnerable to oiling.
Mostrar más [+] Menos [-]Chemical composition of microplastics floating on the surface of the Mediterranean Sea Texto completo
2022
Kedzierski, Mikaël | Palazot, Maialen | Soccalingame, Lata | Falcou-Préfol, Mathilde | Gorsky, Gabriel | Galgani, François | Bruzaud, Stéphane | Pedrotti, Maria Luiza
Chemical composition of microplastics floating on the surface of the Mediterranean Sea Texto completo
2022
Kedzierski, Mikaël | Palazot, Maialen | Soccalingame, Lata | Falcou-Préfol, Mathilde | Gorsky, Gabriel | Galgani, François | Bruzaud, Stéphane | Pedrotti, Maria Luiza
The Mediterranean Sea is one of the most studied regions in the world in terms of microplastic (MP) contamination. However, only a few studies have analysed the chemical composition of MPs at the Mediterranean Sea surface. In this context, this study aims to describe the chemical composition as a function of particle size, mass and number concentrations of MPs collected in the surface waters of the Mediterranean Sea. The chemical composition showed a certain homogeneity at the Mediterranean Sea scale. The main polymers identified by Fourier Transform Infra-Red (FTIR) spectroscopy were poly(ethylene) (67.3 ± 2.4%), poly(propylene) (20.8 ± 2.1%) and poly(styrene) (3.0 ± 0.9%). Nevertheless, discrepancies, confirmed by the literature, were observed at a mesoscale level. Thus, in the North Tyrrhenian Sea, the proportion of poly(ethylene) was significantly lower than the average value of the Mediterranean Sea (57.9 ± 10.5%). Anthropic sources, rivers, or polymer ageing are assumed to be responsible for the variations observed.
Mostrar más [+] Menos [-]Chemical composition of microplastics floating on the surface of the Mediterranean Sea Texto completo
2022
Kedzierski, Mikaël | Palazot, Maialen | Soccalingame, Lata | Falcou-préfol, Mathilde | Gorsky, Gabriel | Galgani, Francois | Bruzaud, Stéphane | Pedrotti, Maria Luiza
The Mediterranean Sea is one of the most studied regions in the world in terms of microplastic (MP) contamination. However, only a few studies have analysed the chemical composition of MPs at the Mediterranean Sea surface. In this context, this study aims to describe the chemical composition as a function of particle size, mass and number concentrations of MPs collected in the surface waters of the Mediterranean Sea. The chemical composition showed a certain homogeneity at the Mediterranean Sea scale. The main polymers identified by Fourier Transform Infra-Red (FTIR) spectroscopy were poly(ethylene) (67.3 ± 2.4%), poly(propylene) (20.8 ± 2.1%) and poly(styrene) (3.0 ± 0.9%). Nevertheless, discrepancies, confirmed by the literature, were observed at a mesoscale level. Thus, in the North Tyrrhenian Sea, the proportion of poly(ethylene) was significantly lower than the average value of the Mediterranean Sea (57.9 ± 10.5%). Anthropic sources, rivers, or polymer ageing are assumed to be responsible for the variations observed.
Mostrar más [+] Menos [-]First inventory of marine debris on Alegranza, an uninhabited island in the Northeast Atlantic Texto completo
2022
Herrera, Alicia | Rivera, J Alexis | Moreno, Teresa | Martínez, Ico | Gómez, May
Alegranza is the most northerly island of the Canary Islands archipelago, the first obstacle crossed by the Canary Current. From July to October 2020, six expeditions were led to the island to make a first inventory of marine debris and its possible source and origin. In total, 3667 objects weighing 321 kg were removed, excluding wooden objects. Of these, 97.7% were plastics, the most abundant being drink bottles (25.4%). While knowing the origin, source and pathway of debris is difficult, legible labels provided valuable information. In Alegranza, 66.7% of the legible bottle labels indicated Asian countries of manufacture, which is evidence that the source is maritime traffic in the region. The lobster trap license labels from the east coast of the United States and Canada were dated from 1999 to 2018, supporting both the exogenous origin and long lifetime in the ocean of these debris.
Mostrar más [+] Menos [-]Assessment of seasonal and spatial variation responses of integrated biomarkers in two marine sentinel bivalve species: Agadir Bay (Southern of Morocco) Texto completo
2022
Chahouri, Abir | Agnaou, Mustapha | El Hanaoui, Mohamed | Yacoubi, Bouchra | Moukrim, Abdellatif | Banaoui, Ali
The present study aims to assess the effects of contamination of the Agadir bay coasts using bivalves as a biomonitoring sentinel species. Seasonal variations of biochemical composition in terms of total protein content and oxidative stress biomarkers including glutathione-S-transferase, malondialdehyde, catalase and acetylcholinesterase were evaluated in the soft tissues of Scrobicularia plana and Donax trunculus specimens. The latter were collected from two sites in Agadir bay during two-year span (2018–2020). The Integrated Biomarker Response Index (IBR) was performed to classify the stress response in both species and to assess the level of exposure to xenobiotics. The data showed maximum annual values of acetylcholinesterase and malondialdehyde for Donax trunculus in Agadir beach (AG) with 6.25 nmol/mn/mg and 3 nmol/mg of protein, respectively. Those of catalase and glutathione-S-transferase for Scrobicularia plana in Oued Souss estuary (OS) were of 4.41 μmol/mn/mg and 14.43 nmol/mn/mg of protein, respectively. The studied species are considered good indicators in aquatic ecosystems.
Mostrar más [+] Menos [-]Model based estimate of transboundary litter pollution on Mediterranean coasts Texto completo
2022
Macías, D. (Diego) | Stips, Adolf | Hanke, Georg
Model based estimate of transboundary litter pollution on Mediterranean coasts Texto completo
2022
Macías, D. (Diego) | Stips, Adolf | Hanke, Georg
Plastic litter pollution is one of the major concerns for the health of marine ecosystems worldwide. This pervasive form of pollution affects all oceans and seas and it's interacting with multiple levels of the marine food webs. In the European context, several pieces of legislation try to fight against this pervasive and ubiquitous form of pollution. Recently, EU Member States have agreed to a maximum threshold of litter items per coast length (20 items/100 m coastline). One major concern among stakeholders to reach this consensus was the transboundary litter, as measures need to be implemented in the country of origin. Henceforth, a solid method to estimate the amounts of the transboundary litter to a given Member State's coasts is needed. In this contribution, we use a combination of hydrodynamic and Lagrangian models for the Mediterranean Sea in order to understand the origin of coastal litter. Simulations show that the amount of transboundary litter in Mediterranean countries could be as large as 30% although both regional and seasonal differences could be significant.
Mostrar más [+] Menos [-]Model based estimate of transboundary litter pollution on Mediterranean coasts Texto completo
2022
Macías, Diego | Stips, Adolf | Hanke, Georg | Consejo Superior de Investigaciones Científicas [https://ror.org/02gfc7t72]
Plastic litter pollution is one of the major concerns for the health of marine ecosystems worldwide. This pervasive form of pollution affects all oceans and seas and it's interacting with multiple levels of the marine food webs. In the European context, several pieces of legislation try to fight against this pervasive and ubiquitous form of pollution. Recently, EU Member States have agreed to a maximum threshold of litter items per coast length (20 items/100 m coastline). One major concern among stakeholders to reach this consensus was the transboundary litter, as measures need to be implemented in the country of origin. Henceforth, a solid method to estimate the amounts of the transboundary litter to a given Member State's coasts is needed. In this contribution, we use a combination of hydrodynamic and Lagrangian models for the Mediterranean Sea in order to understand the origin of coastal litter. Simulations show that the amount of transboundary litter in Mediterranean countries could be as large as 30% although both regional and seasonal differences could be significant. | Peer reviewed
Mostrar más [+] Menos [-]Spatial variation and ecological risk assessment for heavy metals in marsh sediments in Fuzhou reach of the Min River, Southeast China Texto completo
2022
Li, Yajin | Sun, Zhigao | Mao, Li | Hu, Xingyun | Chen, Bingbing | Li, Yanzhe
To explore the pollution levels, sources and risks of heavy metals in sediments in Fuzhou reach of the Min River, the sediments involving in seven marsh types were sampled. Results showed that the concentrations of Pb, Zn and Cd in sediments declined from freshwater segment to estuarine segment. Higher levels of Cu, Cr and Ni in sediments generally occurred in estuarine segment. The highest levels of Pb and Cd were observed in bush swamp, while those of Cr, Ni, Zn and Cu occurred in mudflat. Cr, Cu, Zn and Ni probably shared common source, while Pb and Cd originated from another source. Pb and Cd were identified as heavy metals of primary concerns and the former showed high potential toxicity and high contributions to ΣTUs. Next step, the metal pollutions in sediments might be more serious if effective measures were not taken to control the loading of pollutants.
Mostrar más [+] Menos [-]Identification and determination of optimum growth condition with respect to selected environmental parameters for open sea cultivation of Gracillaria edulis in Andaman water Texto completo
2022
Panja, Atanu | Peter, Malarvizhi J | Nayagi, N. | Maruthupandi, N. | Ganesan, M. | Haldar, Soumya
Gracilaria edulis is one of India's most widely cultivated seaweeds. Pilot scale cultivation of Gracilaria edulis was initiated at Andaman, India for the first time. In the present study attempt has been made to identify how different water quality parameters influence the growth. Total 11 physicochemical parameters and 9 microbiological parameters, as well as chlorophyll and zooplankton, phytoplankton parameters were studied for two different seasons to evaluate which parameters influence seaweed growth. Six (nitrate, nitrite, ammonia, silicate, chlorophyll, photosynthetic active radiation) have a positive impact on seaweed growth, while some of the bacterial species showed negative impact. Lowess 3D curve fit model showed pH range from 7.59 to 7.82, N/P ratio of 2.046, rainfall 23.85–24 mm, and Photosynthetic active radiation of 376.6 W/m² are optimum for Gracillaria growth. This model can be applied to future mass culture.
Mostrar más [+] Menos [-]Hydrogeochemical processes controlling the groundwater salinity in the coastal aquifers of Southern Tamil Nadu, India Texto completo
2022
Selvakumar, S. | Chandrasekar, N. | Srinivas, Y. | Selvam, S. | Kaliraj, S. | Magesh, N.S. | Venkatramanan, S.
The current study identifies groundwater quality issues and investigates the most important geochemical processes that control seawater intrusion using various ionic ratios, hydrochemical facies evolution, and geochemical modelling. Cl₋/Br ratio is an important indicator to identify the origin of groundwater salinity in coastal aquifers. Nineteen percent of the groundwater samples with Cl⁻/Br⁻ ratio similar to that of Standard Mean Ocean Water (SMOW) are affected by seawater intrusion in the study area. Particularly, nine groundwater samples have high chloride values and are similar to SMOW, and it may derived salinity from seawater sources from the Bay of Bengal due to the over-pumping of production wells in the Uvari zone. Five samples are similar to SMOW, which is due to the presence of salt pan activities. The bivariate plots such as Ca²⁺ + Mg²⁺ vs Cl⁻, EC vs Cl⁻, and Na⁺/Cl⁻ ratio indicate that seawater intrusion is the primary source for groundwater salinisation. Evaporation is the dominant process controlling groundwater chemistry, rather than rock-water interaction and precipitation, according to mechanisms controlling groundwater chemistry. Direct ion exchange and converse ion exchange are the critical controlling factors for groundwater salinisation, according to the hydrochemical facies evolution diagram (HFED). The water quality index (WQI) shows that most groundwater belongs to the poor to the marginal category. The saturation indices show that the groundwater samples are saturated with minerals such as dolomite, calcite, aragonite and magnesite. Therefore, these minerals are susceptible to precipitation due to the effective leaching of calcareous minerals from the bedrocks. Compiled hydrogeochemical analysis and multivariate statistical analysis revealed that the Tiruchendur and Uvari zone was affected by the seawater intrusion and led to an increase in the salinity of the groundwater.
Mostrar más [+] Menos [-]First assessment of floating marine litter abundance and distribution in the Bay of Biscay from an integrated ecosystem survey Texto completo
2022
Ruiz, Irene | Burgoa, Iñaki | Santos, Maria | Basurko, Oihane C. | García-Barón, Isabel | Louzao, Maite | Beldarrain, Beatriz | Kukul, Deniz | Valle, Claudia | Uriarte, Ainhize | Rubio, Anna
In the Bay of Biscay, regional monitoring programmes and data on abundance and distribution of floating marine litter are scarce, contrary to many other European marine regions. Here, a joint analysis of multiyear observations (2017–2019) of floating micro and macrolitter and oceanographic conditions was conducted for the Bay of Biscay by combining microlitter samplings with neuston nets and vessel-based macrolitter observations. Results show spatiotemporal abundance and distribution patterns. The density of floating microlitter increased from 26,056 items/km² in 2017 to 1,802,4611 items/km² in 2019; floating macrolitter densities barely varied amongst year (2.52 items/km² in 2017 and 3.70 items/km² in 2019). No significant correlation was found between densities of micro and macrolitter, neither for the oceanographic variables. We conclude that longer micro and macrolitter monitoring periods and standardized datasets based on the cross-border cooperation are needed to collect more comparable information, evaluate trends, and support decision making in the area.
Mostrar más [+] Menos [-]Geochemical baseline establishment and pollution assessment of heavy metals in the largest coastal lagoon (Pinqing Lagoon) in China mainland Texto completo
2022
Xian, Hanbiao | Dong, Xuhui | Wang, Yu | Li, Yan | Xing, Jinhuai | Jeppesen, Erik
Establishing geochemical baselines and assessment of heavy metal pollution in lagoon sediments are critical for providing guidance to coastal zone environmental management. We analyzed heavy metals in high-resolution sediment cores from Pinqing Lagoon in South China, and defined the baselines of common pollution elements with a significant anthropogenic contribution. With these baselines, a spatiotemporal pollution assessment revealed Cu and Cd as the predominant pollution metals in both core and surface sediments, although the ecological risk level in the interior lagoon remained low during the past ~170 years. Surface sediment pollution status indicate a significant spatial difference. The findings from this typical coastal lagoon evidence a strong self-clean capacity attributable to the frequent water-mass-energy exchange between the lagoon and the sea. Furthermore, despite the significant impact by the sea, the geochemical baselines are close to the catchment soil backgrounds that can be defined using a paleolimnological approach.
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