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Effectiveness of mechanical recovery for large offshore oil spills Полный текст
2021
Etkin, Dagmar Schmidt | Nedwed, Tim J.
Mechanical recovery for large offshore oil spills (defined as the marine environment over 10 km from shore outside of bays, lagoons, and marinas) depends on oil behavior, environmental conditions, equipment specifications, and operational issues. These factors limit oil recovery with booms and skimmers. The “rule of thumb” has been that 10–30% of the total oil spilled can be recovered. This paper describes a review of historical oil spills that found only between 2 and 6% of the total oil spilled was recovered.The limiting factors affecting mechanical recovery in offshore settings include environmental conditions, oil behavior, and logistics. Mechanical recovery will always be an important tool for spill response, especially in nearshore and in-port settings, as well as locations with sensitivity to chemical dispersants and/or in situ burning. However, its application in large offshore spills will generally result in recovery of only a fraction of the spilled oil.
Показать больше [+] Меньше [-]Microbial Interactions in Pollution Control Ecosystems Полный текст
2021
Yin, Qidong | Feng, Zhaolu | Hu, Yuansheng | Zhan, Xinmin | Wu, Guangxue
PURPOSE OF REVIEW: Microbial interaction determines the performance, stability, and resilience of the microbial communities. Understanding microbial interactions benefits the development of environmental biotechnology. The purpose of this review is to summarize the recent findings of microbial interactions in pollution control ecosystems from aspects of the substrate degradation, energy utilization, electron transfer, and information exchange. RECENT FINDINGS: Cross-feeding of substrates such as vitamins was found to be necessary for the degradation of some trace organic contaminants. Under different conditions, microorganisms can mediate various energy-utilization pathways (e.g., co-metabolism) to grow. Electroactive bacteria and cable bacteria can mediate extracellular electron transfer via conductive pili, c-type cytochrome, or filamentous structure. Quorum sensing plays an important role in the microbial aggregation and functional microbe enrichments. With all these knowledges, it will potentially benefit the development of disruptive environmental biotechnologies. This review summarized recent findings of microbial interactions, many of which have huge potentials to advance environmental biotechnologies. Multi-omics methods should be further applied for comprehensively confirming known and unknown microbial processes. The co-occurrence network should be applied to unravel the interlinks among substrate degradation, energy utilization, electron transfer, and information exchange. The proper regulation of microbial interactions in practical application should be further addressed.
Показать больше [+] Меньше [-]Pathways of floating marine debris in Jakarta Bay, Indonesia Полный текст
2021
Iskandar, Mochamad Riza | Surinati, Dewi | Cordova, Muhammad Reza | Siong, Kian
Jakarta is the capital of Indonesia with a high population density, which affects the amount of waste generated. The waste that ends up in Jakarta Bay has become an environmental problem. Understanding the pathway of marine debris in the ocean is important to identify the mitigation strategies. Before this study, the pathways and sources of marine debris in Jakarta Bay were unknown. By using virtual floating marine debris particles in a high-resolution ocean model, the fate of marine debris based on the pathways of particles released in Jakarta Bay in both forward and backward tracking experiments was analyzed. It was found that most of the particles from Jakarta Bay flow toward the Indian Ocean in all seasons. They flow off through the Sunda Strait and reach the open Indian Ocean after a few weeks. With regard to the source location, most particles that end up in Jakarta Bay come from the north of Java Island locally and from the Gulf of Thailand, Sumatra, and Kalimantan coasts. The particles do not appear to vary significantly across all seasons and identifying the pathway of marine debris might be useful in pollution reduction.
Показать больше [+] Меньше [-]Tourists' perception of beach litter and willingness to participate in beach clean-up Полный текст
2021
Adam, Issahaku
While tourists contribute to and suffer the consequences of beach litter, studies on beach clean-up exercises have mostly neglected them and overly focused on resident beach goers. Based on a sample of 685 international tourists in Ghana, this paper examines the perception of international tourists on beach litter and the determinants of their willingness to participate in beach clean-up as an experiential activity during their visits to Ghanaian beaches. The findings reveal that international tourists have negative perceptions of beach litter, constructed along four domains, namely health, recreational activity participation, aesthetic, and coastal environment. Further, sex, age, educational attainment, continent of origin, travel party status, environmental value, and perception of beach litter significantly influence the willingness of the tourists to participate in beach clean-ups. The implications of these findings in the context of beach litter management at coastal resorts and destinations are discussed.
Показать больше [+] Меньше [-]Climate change impacts on pollutants mobilization and interactive effects of climate change and pollutants on toxicity and bioaccumulation of pollutants in estuarine and marine biota and linkage to seafood security Полный текст
2021
Kibria, Golam | Nugegoda, Dayanthi | Rose, Gavin | Haroon, A.K Yousuf
This article provides an overview of the impacts of climate change stressors (temperature, ocean acidification, sea-level rise, and hypoxia) on estuarine and marine biota (algae, crustaceans, molluscs, corals, and fish). It also assessed possible/likely interactive impacts (combined impacts of climate change stressors and pollutants) on pollutants mobilization, pollutants toxicity (effects on growth, reproduction, mortality) and pollutants bioaccumulation in estuarine and marine biota. An increase in temperature and extreme events may enhance the release, degradation, transportation, and mobilization of both hydrophobic and hydrophilic pollutants in the estuarine and marine environments. Based on the available pollutants' toxicity trend data and information it reveals that the toxicity of several high-risk pollutants may increase with increasing levels of climate change stressors. It is likely that the interactive effects of climate change and pollutants may enhance the bioaccumulation of pollutants in seafood organisms. There is a paucity of literature relating to realistic interactive effects of climate change and pollutants. Therefore, future research should be directed towards the combined effects of climate change stressors and pollutants on estuarine and marine bota. A sustainable solution for pollution control caused by both greenhouse gas emissions (that cause climate change) and chemical pollutants would be required to safeguard the estuarine and marine biota.
Показать больше [+] Меньше [-]Ocean acidification interacts with growth light to suppress CO2 acquisition efficiency and enhance mitochondrial respiration in a coastal diatom Полный текст
2021
Qu, Liming | Campbell, Douglas A. | Gao, Kunshan
Ocean acidification interacts with growth light to suppress CO2 acquisition efficiency and enhance mitochondrial respiration in a coastal diatom Полный текст
2021
Qu, Liming | Campbell, Douglas A. | Gao, Kunshan
Diatom responses to ocean acidification have been documented with variable and controversial results. We grew the coastal diatom Thalassiosira weissflogii under 410 (LC, pH 8.13) vs 1000 μatm (HC, pH 7.83) pCO₂ and at different levels of light (80, 140, 220 μmol photons m⁻² s⁻¹), and found that light level alters physiological responses to OA. CO₂ concentrating mechanisms (CCMs) were down-regulated in the HC-grown cells across all the light levels, as reflected by lowered activity of the periplasmic carbonic anhydrase and decreased photosynthetic affinity for CO₂ or dissolved inorganic carbon. The specific growth rate was, however, enhanced significantly by 9.2% only at the limiting low light level. These results indicate that rather than CO₂ “fertilization”, the energy saved from down-regulation of CCMs promoted the growth rate of the diatom when light availability is low, in parallel with enhanced respiration under OA to cope with the acidic stress by providing extra energy.
Показать больше [+] Меньше [-]Seawater carbonate chemistry and CO2 acquisition efficiency and mitochondrial respiration in a coastal diatom Полный текст
2021
Qu, Liming | Campbell, Douglas A | Gao, Kunshan
Diatom responses to ocean acidification have been documented with variable and controversial results. We grew the coastal diatom Thalassiosira weissflogii under 410 (LC, pH 8.13) vs 1000 μatm (HC, pH 7.83) pCO2 and at different levels of light (80, 140, 220 μmol photons/m**2/s), and found that light level alters physiological responses to OA. CO2 concentrating mechanisms (CCMs) were down-regulated in the HC-grown cells across all the light levels, as reflected by lowered activity of the periplasmic carbonic anhydrase and decreased photosynthetic affinity for CO2 or dissolved inorganic carbon. The specific growth rate was, however, enhanced significantly by 9.2% only at the limiting low light level. These results indicate that rather than CO2 “fertilization”, the energy saved from down-regulation of CCMs promoted the growth rate of the diatom when light availability is low, in parallel with enhanced respiration under OA to cope with the acidic stress by providing extra energy.
Показать больше [+] Меньше [-]Microplastics in different tissues of some commercially important fish species from Anzali Wetland in the Southwest Caspian Sea, Northern Iran Полный текст
2021
Rasta, Majid | Sattari, Masoud | Taleshi, Mojtaba S. | Namin, Javid Imanpour
The aim of this study was to investigate the occurrence of microplastics (MPs) in the gastrointestinal (GI) tract, muscle and gonads of 193 individuals of nine commercially-important fish species from Anzali Wetland between May and July 2018. Tissues were removed, digested by 10% KOH for 24 h at 60 °C, filtered on cellulose nitrate filter and then dried. MPs were found in all tissues. There were significant differences between the numbers of isolated particles from GI tract and control groups (procedural blank containing Milli Q water without tissue), while their abundance in the muscle and gonads did not display significant differences with control groups. Higher abundances of MPs were recorded in omnivorous fish (2.26 ± 2.93 items/individual) than carnivorous species (1.10 ± 1.10 items/individual) (P < 0.05). MPs were ranged from 20 to 4800 μm in size and were dominated by fiber-like in shape, polyethylene in polymer and black in color.
Показать больше [+] Меньше [-]Trace element concentration and Al/Fe ratio in sediments of the South East Mediterranean Sea Полный текст
2021
Abbasi, Akbar | Salihoglu, Ilkay | Mirekhtiary, Fatemeh
The heavy metals (HMs) concentration range, the metal/Al and metal/Fe value were determined in the sediment in order to evaluate the correlation coefficient of HMs at the regions of South East Mediterranean Sea, Cyprus. The results showed that the mean concentrations of the HMs in the sediment samples followed the order Al > Fe > Mn > Cr > Ni > Zn > Cu > Pb > As>Hg, respectively. The pollution indices of contamination factor (CF), geoaccumulation index (Igeo), enrichment factor (EF), and soil pollution index (SPI) were calculated. The Igeo, CF and EF values for Cu were obtained moderately to strongly polluted, moderate contamination and moderately severe enrichment, respectively. The remaining elements indicated unpolluted or low contamination results. Also, SPI indicated a low level of contamination for the all of the metals. The cluster analysis of data set indicates that the HMs are separated with 50% similarity in two categories of Al category (As, Pb, Cr, Ni) and Fe category (Mn, Zn, Cu, Hg).
Показать больше [+] Меньше [-]First insight into plastics ingestion by fish in the Gulf of California, Mexico Полный текст
2021
Salazar-Pérez, C. | Amezcua, F. | Rosales-Valencia, A. | Green, L. | Pollorena-Melendrez, J.E. | Sarmiento-Martínez, M.A. | Tomita Ramírez, I. | Gil-Manrique, B.D. | Hernandez-Lozano, M.Y. | Muro-Torres, V.M. | Green-Ruiz, C. | Piñon-Colin, T.D.J. | Wakida, F.T. | Barletta, M.
Plastic particle occurrence in the digestive tracts of fishes from a tropical estuarine system in the Gulf of California was investigated. A total of 1095 fish were analysed, representing 15 species. In total 1384 particles of plastic debris were recovered from the gastrointestinal tracts of 552 specimens belonging to 13 species, and all consisted of threads, the majority of which were small microplastics (0.23 to 1.89), followed by large microplastics (2.07 to 4.49), and few mesoplastics (5.4 to 19.86). Plastic particles were identified using ATR-FTIR spectroscopy. The mean frequency of occurrence of plastics in the gastrointestinal tracts of fishes from this system was 50.5%, which is higher than frequencies reported in similar systems in other areas. The polymers identified by ATR-FTIR were polyamide (51.2%), polyethylene (36.6%), polypropylene (7.3%), and polyacrylic (4.9%). These results show the first evidence of plastic contamination for estuarine biota in the Gulf of California.
Показать больше [+] Меньше [-]Spatio-seasonal microplastics distribution along a shallow coastal lagoon ecocline within a marine conservation unit Полный текст
2021
Lorenzi, Luciano | Reginato, Bruna C. | Mayer, Devon G. | Gentil, Eduardo | Pezzin, Ana Paula Testa | Silveira, Victória Fonseca | Dantas, David V.
The aim of our study is to estimate the abundance and sources of floating microplastics (MPs) along a coastal lagoon ecocline in a marine conservation unit (MCU) for implementing effective prevention and mitigation actions in South Brazil. MPs were sampled monthly, and the abundance and size were determined for hard solids, soft plastic, plastic filaments, and paint fragments. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) analysis was performed, and the MPs were classified as polyethylene, polyester, polypropylene, polybutadiene, and polystyrene. Downstream areas (outside of the MCU) showed high levels of MPs, during the winter, due to low precipitation and the predominance of S/SE winds. During summer, precipitation increases, and MPs are exported with surface runoff, resulting in lower level of MPs. Outside MCU areas, a high concentration of tourism houses, commercials, and artisanal fisheries were observed, which could contribute to all types of plastic debris found in our study.
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