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Optical quantification of oil emulsions in multi-band coarse-resolution imagery using a lab-derived HSV model 全文
2022
Jiao, Junnan | Lu, Yingcheng | Liu, Yongxue
Oil emulsions can harm marine and coastal environments for extended periods. Timely identification and quantification of oil emulsions are essential for oil spill response. Although SAR is the most commonly used technique in detecting oil presence, it has limits in oil quantification. In contrast, optical remote sensing can fill this gap with more spectral bands. Hyperspectral remote sensing is capable of achieving this purpose. However, it is challenging to use multi-band coarse-resolution imagery due to the fewer bands and mixed pixel effect. Through laboratory measurements, numerical simulation, and Hue-Saturation-Value (HSV) model, we illuminate the multispectral mixed characteristics of oil emulsions and demonstrate Hue's role in characterizing the mixture features and oil concentration trends. Hue-based oil emulsion classification and oil concentration segmentation (OCS) methods are proposed and applied to Landsat-5 images under quantified uncertainties. This approach is expected to expand its application in multispectral remote sensing.
显示更多 [+] 显示较少 [-]Roles of Atmospheric Aerosols in Extreme Meteorological Events: a Systematic Review 全文
2022
Wang, Zilin | Xue, Lian | Liu, Jingyi | Ding, Ke | Lou, Sijia | Ding, Aijun | Wang, Jiandong | Huang, Xin
PURPOSE OF REVIEW: Atmospheric aerosol from both natural and anthropogenic activities has long been acknowledged as one of the important factors influencing regional and global climate change. Many regions around the globe experienced high aerosol loadings because of intensive emissions, yet the roles of atmospheric aerosols in extreme meteorological and air pollution events have not been well demonstrated due mainly to the complexity of atmospheric physical and chemical interaction at mesoscale and even microscale. Here, we present a comprehensive review of current understanding on the role of atmospheric aerosols in the development and evolution of extreme meteorological events, including monsoon circulation, heat waves, extreme rainfall, tornadoes, and severe air pollution. RECENT FINDINGS: Aerosols could participate in the development of meteorological systems through direct and indirect effects. Large-scale precipitation from shallow stratiform clouds was found to be suppressed by aerosols, while invigoration effects contribute to deep convection and even catastrophic floods in local areas. The occurrence of high-impact weather such as tornadoes and tropical cyclone is also related to aerosol concentration and distribution. Moreover, a positive feedback between aerosols and boundary layer meteorology is proposed as an important factor conducive to heavy haze pollution over urban areas. The work underscores the great importance of aerosols’ meteorological feedback in extreme weather events. Integrated observations and seamless coupling of meteorology and atmospheric chemistry in models are highlighted for future studies to fill the knowledge gap in current research.
显示更多 [+] 显示较少 [-]Anthropogenic pressure leads to more introductions: Marine traffic and artificial structures in offshore islands increases non-indigenous species 全文
2022
Castro, Nuno | Gestoso, Ignacio | Marques, Carolina S. | Ramalhosa, Patrício | Monteiro, João G. | Costa, José L. | Canning-Clode, João
Anthropogenic pressures such as the introduction of non-indigenous species (NIS) have impacted global biodiversity and ecosystems. Most marine species spreading outside their natural biogeographical limits are promoted and facilitated by maritime traffic through ballast water and hull biofouling. Propagule pressure plays a primary role in invasion success mixed with environmental conditions of the arrival port. Moreover, with the current ocean sprawl, new substrates are offered for potential NIS recruits. Here, differences in the fouling assemblages thriving inside three different ports/marinas facilities in Madeira Island were assessed for comparison. The locations showed significant differences concerning assemblage structure. Most NIS were detected in plastic floating pontoons. Funchal harbour receives most of the marine traffic in Madeira, acting as the main hub for primary NIS introductions, being recreational boating involved in NIS secondary transfers. Our results highlight the need for future management actions in island ecosystems, particularly monitoring and sampling of recreational boating.
显示更多 [+] 显示较少 [-]Additives, plasticizers, small microplastics (<100 μm), and other microlitter components in the gastrointestinal tract of commercial teleost fish: Method of extraction, purification, quantification, and characterization using Micro-FTIR 全文
2022
Corami, Fabiana | Rosso, Beatrice | Sfriso, Andrea Augusto | Gambaro, Andrea | Mistri, Michele | Munari, Cristina | Barbante, Carlo
One of the aims of this study is the development of a pretreatment method for additives, plasticizers and other components of micro-litter (APFs), and small microplastics (SMPs <100 μm) in the gastrointestinal tract (GIT) of five of the most widely distributed and consumed commercial fish species, Engraulis encrasiculos, Sardina pilchardus, Mullus surmuletus, Solea solea, and Sparus aurata. The second aim was to develop a simultaneous quantification and identification method via Micro-FTIR of APFs and SMPs ingested by these commercial fish species. The distribution of SMPs and APFs is characteristically different for each species investigated. E. encrasiculos and S. pilchardus had a higher weight of SMPs than the other species investigated. Regarding APFs, the highest abundance was observed in E. encrasiculos. This study highlights the importance of studying additives and plasticizers that can be used as efficient proxies of microplastics, as shown by the presence of vulcanizing agents such as Vanax®.
显示更多 [+] 显示较少 [-]Dinoflagellates cyst assemblage concerning trophic index for eutrophication from major ports along the west coast of India 全文
2022
Rodrigues, R.V. | Patil, J.S. | Anil, A.C.
An overview of dinoflagellates cysts assemblage is presented as a trophic index for three monsoon-influenced estuarine and marine ports along the Indian coast. The cyst distribution (including harmful species) showed a trend of highest abundance and species number in highly eutrophicated estuarine (Cochin-south) followed by medium (New-Mangalore-central) and low (Kandla-north) levels of eutrophicated marine ports. The investigation revealed four new species in the region (Bitectatodinium spongium, Gonyaulax elongatum, Brigantedinium sp. and potential harmful species Blixaea quinquecornis-cyst similar to planktonic). Autotrophs dominance in the highly productive Cochin and New-Mangalore ports reveals that, in eutrophic systems, heterotrophs need not always be dominant. The indicator taxa (Polykrikos, Protoperidnium, and Lingulodinium) presence in high density indicated a eutrophic system. This study concludes cyst (species numbers/Fisher-α index/indicator species) as potential eutrophication proxies and emphasizes greater harmful-algal-bloom risks in the high trophic-index ports (Cochin and New-Mangalore).
显示更多 [+] 显示较少 [-]A novel report on phthalates levels in Biscayne Bay surface waters and drinking water from South Florida 全文
2022
Cui, Danni | Ricardo, Melissa | Quinete, Natalia
In this research, we have developed and validated a modified version of the U.S.EPA method 506 using a liquid-liquid extraction method followed by gas-chromatography mass spectrometry analysis to assess the occurrence and spatial and seasonal variation of six phthalates (di(2-ethylhexyl) phthalate-DEHP, dibutyl phthalate-DBP, butyl benzyl phthalate-BBP, diethyl phthalate-DEP, dimethyl phthalate-DMP, and di-n-octyl phthalate-DOP) in surface and tap waters from South Florida, collected during the wet and dry seasons. The most frequently detected phthalate was DEHP, with concentrations up to 1.56 μg/L in surface water. Higher DEHP concentrations were observed in tap water during the wet season, which aligns with the higher temperature during the summer months facilitating leaching from plastic materials. Preliminary ecological and human health risk assessments suggested low hazard risk based on concentrations observed in tap and surface waters, respectively. PAEs could however still constitute a great concern to sensitive marine species, including early stages organisms and coral reefs.
显示更多 [+] 显示较少 [-]Microbial pioneers of plastic colonisation in coastal seawaters 全文
2022
Latva, Mira | Dedman, Craig J. | Wright, Robyn J. | Polin, Marco | Christie-Oleza, Joseph A.
Plastics, when entering the environment, are immediately colonised by microorganisms. This modifies their physico-chemical properties as well as their transport and fate in natural ecosystems, but whom pioneers this colonisation in marine ecosystems? Previous studies have focused on microbial communities that develop on plastics after relatively long incubation periods (i.e., days to months), but very little data is available regarding the earliest stages of colonisation on buoyant plastics in marine waters (i.e., minutes or hours). We conducted a preliminary study where the earliest hours of microbial colonisation on buoyant plastics in marine coastal waters were investigated by field incubations and amplicon sequencing of the prokaryotic and eukaryotic communities. Our results show that members of the Bacteroidetes group pioneer microbial attachment to plastics but, over time, their presence is masked by other groups – Gammaproteobacteria at first and later by Alphaproteobacteria. Interestingly, the eukaryotic community on plastics exposed to sunlight became dominated by phototrophic organisms from the phylum Ochrophyta, diatoms at the start and brown algae towards the end of the three-day incubations. This study defines the pioneering microbial community that colonises plastics immediately when entering coastal marine environments and that may set the seeding Plastisphere of plastics in the oceans.
显示更多 [+] 显示较少 [-]Interactive effects of temperature and salinity on the growth and cytotoxicity of the fish-killing microalgal species Heterosigma akashiwo and Pseudochattonella verruculosa 全文
2022
Sandoval-Sanhueza, Alondra | Aguilera-Belmonte, Alejandra | Basti, Leila | Figueroa, Rosa I. | Molinet, Carlos | Álvarez, Gonzalo | Oyanedel, Sandra | Riobó, Pilar | Mancilla-Gutiérrez, Guido | Díaz, Patricio A.
Interactive effects of temperature and salinity on the growth and cytotoxicity of the fish-killing microalgal species Heterosigma akashiwo and Pseudochattonella verruculosa 全文
2022
Sandoval-Sanhueza, Alondra | Aguilera-Belmonte, Alejandra | Basti, Leila | Figueroa, Rosa I. | Molinet, Carlos | Álvarez, Gonzalo | Oyanedel, Sandra | Riobó, Pilar | Mancilla-Gutiérrez, Guido | Díaz, Patricio A.
Fish-killing blooms of Heterosigma akashiwo and Pseudochattonella verruculosa have been devastating for the farmed salmon industry, but in Southern Chile the conditions that promote the growth and toxicity of these microalgae are poorly understood. This study examined the effects of different combinations of temperature (12, 15, 18 °C) and salinity (10, 20, 30 psu) on the growth of Chilean strains of these two species. The results showed that the optimal growth conditions for H. akashiwo and P. verruculosa differed, with a maximum rate of 0.99 day⁻¹ obtained at 15 °C and a salinity of 20 psu for H. akashiwo, and a maximum rate of 1.06 day⁻¹ obtained at 18 °C and a salinity of 30 psu for P. verruculosa. Cytotoxic assays (2 × 10¹ – 2 × 10⁵ cell mL⁻¹; cells, filtrates, and cell lysates) performed at salinities of 20 and 30 psu showed a 100% reduction in the viability of embryonic fish cells exposed to intact cells of H. akashiwo and a 39% reduction following exposure to culture filtrates of P. verruculosa. Differences in the fish-killing mechanisms (direct cell contact vs. extracellular substances) and physiological traits of H. akashiwo and P. verruculosa explain the recent occurrence of very large blooms under contrasting (cold-brackish vs. hot-salty) extreme climate conditions in Chile.
显示更多 [+] 显示较少 [-]Interactive effects of temperature and salinity on the growth and cytotoxicity of the fish-killing microalgal species Heterosigma akashiwo and Pseudochattonella verruculosa 全文
2022
Sandoval, Alondra | Aguilera-Belmonte, Alejandra | Basti, Leila | Figueroa, Rosa Isabel | Molinet, Carlos | Álvarez, Gonzalo | Oyanedel, Sandra | Riobó, Pilar | Mancilla-Gutiérrez, Guido | Díaz, Patricio Andrés | Agencia Nacional de Investigación y Desarrollo (Chile) | Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias (Chile)
12 pages, 7 figures, 3 tables | Fish-killing blooms of Heterosigma akashiwo and Pseudochattonella verruculosa have been devastating for the farmed salmon industry, but in Southern Chile the conditions that promote the growth and toxicity of these microalgae are poorly understood. This study examined the effects of different combinations of temperature (12, 15, 18 °C) and salinity (10, 20, 30 psu) on the growth of Chilean strains of these two species. The results showed that the optimal growth conditions for H. akashiwo and P. verruculosa differed, with a maximum rate of 0.99 day−1 obtained at 15 °C and a salinity of 20 psu for H. akashiwo, and a maximum rate of 1.06 day−1 obtained at 18 °C and a salinity of 30 psu for P. verruculosa. Cytotoxic assays (2 × 101 – 2 × 105 cell mL−1; cells, filtrates, and cell lysates) performed at salinities of 20 and 30 psu showed a 100% reduction in the viability of embryonic fish cells exposed to intact cells of H. akashiwo and a 39% reduction following exposure to culture filtrates of P. verruculosa. Differences in the fish-killing mechanisms (direct cell contact vs. extracellular substances) and physiological traits of H. akashiwo and P. verruculosa explain the recent occurrence of very large blooms under contrasting (cold-brackish vs. hot-salty) extreme climate conditions in Chile | This study was funded by project REDI170575 (Patricio A. Díaz) from the International Cooperation Programme of the National Agency for Research and Development (ANID), Chile. Dr. Carlos Molinet was funded by the FONDAP Project N° 15110027 (INCAR) | Peer reviewed
显示更多 [+] 显示较少 [-]Interactive effects of temperature and salinity on the growth and cytotoxicity of the fish-killing microalgal species Heterosigma akashiwo and Pseudochattonella verruculosa 全文
2021
Sandoval-Sanhueza, A | Aguilera-Belmonte, A | Figueroa, Rosa Isabel | Molinet, C | Alvarez, G. | Oyanedel, S. | Riobó, Pilar | Mancilla-Gutierrez, G. | Díaz, P.
Fish-killing blooms of Heterosigma akashiwo and Pseudochattonella verruculosa have been devastating for the farmed salmon industry, but in Southern Chile the conditions that promote the growth and toxicity of these microalgae are poorly understood. This study examined the effects of different combinations of temperature (12, 15, 18 °C) and salinity (10, 20, 30 psu) on the growth of Chilean strains of these two species. The results showed that the optimal growth conditions for H. akashiwo and P. verruculosa differed, with a maximum rate of 0.99 day−1 obtained at 15 °C and a salinity of 20 psu for H. akashiwo, and a maximum rate of 1.06 day−1 obtained at 18 °C and a salinity of 30 psu for P. verruculosa. Cytotoxic assays (2 × 101 – 2 × 105 cell mL−1; cells, filtrates, and cell lysates) performed at salinities of 20 and 30 psu showed a 100% reduction in the viability of embryonic fish cells exposed to intact cells of H. akashiwo and a 39% reduction following exposure to culture filtrates of P. verruculosa. Differences in the fish-killing mechanisms (direct cell contact vs. extracellular substances) and physiological traits of H. akashiwo and P. verruculosa explain the recent occurrence of very large blooms under contrasting (cold-brackish vs. hot-salty) extreme climate conditions in Chile. | SI
显示更多 [+] 显示较少 [-]First long-term assessment of metals and associated ecological risk in subtidal sediments of a human-impacted SW Atlantic estuary 全文
2022
Truchet, D.M. | Buzzi, N.S. | Negrin, V.L. | Botté, S.E. | Marcovecchio, J.E.
First long-term assessment of metals and associated ecological risk in subtidal sediments of a human-impacted SW Atlantic estuary 全文
2022
Truchet, D.M. | Buzzi, N.S. | Negrin, V.L. | Botté, S.E. | Marcovecchio, J.E.
The main objective of this article was to profile the metal accumulation, sources, pollution levels and trends during 6 years in a SW Atlantic coastal system (Bahía Blanca estuary). Subtidal sediment samples were taken from six stations with different human impacts, and chemical element analyses were performed using ICP-OES. As a result, metals tended to increase in time and differences were observed between a site profoundly impacted by sewage waters and the rest of the sampling stations. Values range from background levels to those considered toxic for the marine biota, as in the case of Cd and Cu. Besides, the geochemical analyses exhibited low to moderate pollution with probable adverse biological effects. Finally, the physicochemical parameters of the water column like pH and DO significantly decreased in time in all stations and temperature correlated with some metals, indicating a potential interaction.
显示更多 [+] 显示较少 [-]First long-term assessment of metals and associated ecological risk in subtidal sediments of a human-impacted SW Atlantic estuary 全文
2022
Truchet, Daniela María | Buzzi, Natalia Sol | Negrin, Vanesa Lorena | Botté, Sandra Elizabeth | Marcovecchio, Jorge Eduardo
The main objective of this article was to profile the metal accumulation, sources, pollution levels and trends during 6 years in a SW Atlantic coastal system (Bahía Blanca estuary). Subtidal sediment samples were taken from six stations with different human impacts, and chemical element analyses were performed using ICP-OES. As a result, metals tended to increase in time and differences were observed between a site profoundly impacted by sewage waters and the rest of the sampling stations. Values range from background levels to those considered toxic for the marine biota, as in the case of Cd and Cu. Besides, the geochemical analyses exhibited low to moderate pollution with probable adverse biological effects. Finally, the physicochemical parameters of the water column like pH and DO significantly decreased in time in all stations and temperature correlated with some metals, indicating a potential interaction. | Fil: Truchet, Daniela María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina | Fil: Buzzi, Natalia Sol. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina | Fil: Negrin, Vanesa Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina | Fil: Botté, Sandra Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina | Fil: Marcovecchio, Jorge Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; Argentina
显示更多 [+] 显示较少 [-]Biomass and nutrient dynamics of major green tides in Ireland: Implications for biomonitoring 全文
2022
Bermejo, Ricardo | Golden, Nessa | Schrofner, Elena | Knöller, Kay | Fenton, O. (Owen) | Serrão, Ester | Morrison, Liam
Biomass and nutrient dynamics of major green tides in Ireland: Implications for biomonitoring 全文
2022
Bermejo, Ricardo | Golden, Nessa | Schrofner, Elena | Knöller, Kay | Fenton, O. (Owen) | Serrão, Ester | Morrison, Liam
The control of macroalgal bloom development is central for protecting estuarine ecosystems. The identification of the nutrients limiting the development of macroalgal blooms, and their most likely sources is crucial for management strategies. Three Irish estuaries (Argideen, Clonakilty and Tolka) affected by green tides were monitored from June 2016 to August 2017. During each sampling occasion, biomass abundances, tissue N and P contents, and δ¹⁵N were determined for tubular and laminar morphologies of Ulva. All estuaries showed maximum biomass during summer and minimum during winter. Tissue nutrient contents revealed P rather than N limitation. The δ¹⁵N during the peak bloom indicated agriculture as the most likely source of nitrogen in the Argideen and Clonakilty, and urban wastewaters in the Tolka. No differences in the δ¹⁵N, and the tissue nutrients content were observed between morphologies. The period between May and July is most suitable for bioassessment of green tides.
显示更多 [+] 显示较少 [-]Biomass and nutrient dynamics of major green tides in Ireland: Implications for biomonitoring 全文
2022
Bermejo, Ricardo | Golden, Nessa | Schrofner, Elena | Knöller, Kay | Fenton, Owen | Serrao, Ester | Morrison, Liam
The control of macroalgal bloom development is central for protecting estuarine ecosystems. The identification of the nutrients limiting the development of macroalgal blooms, and their most likely sources is crucial for management strategies. Three Irish estuaries (Argideen, Clonakilty and Tolka) affected by green tides were monitored from June 2016 to August 2017. During each sampling occasion, biomass abundances, tissue N and P contents, and δ15N were determined for tubular and laminar morphologies of Ulva. All estuaries showed maximum biomass during summer and minimum during winter. Tissue nutrient contents revealed P rather than N limitation. The δ15N during the peak bloom indicated agriculture as the most likely source of nitrogen in the Argideen and Clonakilty, and urban wastewaters in the Tolka. No differences in the δ15N, and the tissue nutrients content were observed between morphologies. The period between May and July is most suitable for bioassessment of green tides. | info:eu-repo/semantics/publishedVersion
显示更多 [+] 显示较少 [-]Biomass and nutrient dynamics of major green tides in Ireland: Implications for biomonitoring 全文
2022
Bermejo Lacida, Ricardo | Golden, Nessa | Schrofner, Elena | Knöller, Kay | Fenton, Owen | Serrao, Ester | Morrison, Liam | Biología
The control of macroalgal bloom development is central for protecting estuarine ecosystems. The identification of the nutrients limiting the development of macroalgal blooms, and their most likely sources is crucial for management strategies. Three Irish estuaries (Argideen, Clonakilty and Tolka) affected by green tides were monitored from June 2016 to August 2017. During each sampling occasion, biomass abundances, tissue N and P contents, and delta15N were determined for tubular and laminar morphologies of Ulva. All estuaries showed maximum biomass during summer and minimum during winter. Tissue nutrient contents revealed P rather than N limitation. The delta15N during the peak bloom indicated agriculture as the most likely source of nitrogen in the Argideen and Clonakilty, and urban wastewaters in the Tolka. No differences in the delta15N, and the tissue nutrients content were observed between morphologies. The period between May and July is most suitable for bioassessment of green tides. | This work has been co-financed under the 2014-2020 EPA Research Strategy (Environmental Protection Agency, Ireland), project no: 2015- W-MS-20 (the Sea-MAT Project) and project no: 2018-W-MS-32 (the MACRO-MAN Project), and the 2014-2020 ERDF Operational Programme and by the Department of Economy, Knowledge, Business and University of the Regional Government of Andalusia (Project reference: FEDER-UCA18-106875). The authors are thankful to Moya O’Donnell, Maria Galindo-Ponce, Claudia Cara-Ortega, Micheal Mac Monagail, Ana Mendes, Charlene Linderhof, Nichole Keogh, Andrew Niven and Edna Curley for field assistance and Robert Wilkes for advice.
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