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The utility of jellyfish as marine biomonitors
2021
Templeman, Michelle A. | McKenzie, Madeline R. | Kingsford, Michael J.
Jellyfish are abundant in coastal waters across broad latitudinal ranges and are often considered pests and a group that can cause phase shifts in marine ecosystems. Recent studies have highlighted their potential as biomonitors of contaminants including metals, herbicides and nutrients. Traditionally, sedentary organisms like molluscs and annelid worms have been used, but some jellyfish have similar characteristics of localised distributions and in some cases sedentary behaviour. Broad gradients in contaminant accumulation have been shown for a number of planktonic jellyfish species. An alternative biomonitoring candidate is the tropical/sub-tropical upside-down jellyfish (Cassiopea spp.). In laboratory and field deployments, Cassiopea accumulate measurable contaminants over days to weeks, making them ideal for detecting short-term pulses. Furthermore, the decay curve of contaminants varies temporally post-exposure and contaminant type. This can provide an estimate of the timing of exposure. Cassiopea, along with other jellyfish, have the potential to be an interesting and valuable group of organisms for monitoring coastal impacts.
显示更多 [+] 显示较少 [-]A seasonal comparison of litter impacts along the Viña del Mar - Concón coastal strip, Valparaiso region of Chile
2021
Barría-Herrera, José | Vergara-Cortés, Hernán | Contreras-López, Manuel | Rangel-Buitrago, Nelson
The Vina del Mar - Concón Coastal strip is well known for its urban beaches, which play an essential role in the national economy. With extreme urban development, these beaches have become more polluted by litter. This paper evaluates the abundance, spatio-temporal distribution, typology, and sources of beach litter in 14 sectors located inside this coastal strip. A total of 19,886 litter items were collected and grouped into 50 different categories (11 litter typologies). Overall average litter abundance was 0.21 items/m² while during the fall and winter averages were 0.25 items/m² and 0.17 items/m². Values changed along the area and between seasons. Plastics, cigarette butts and paper-cardboard typologies dominated the samples with 42% (0.088 items/m²), 25.4% (0.053 items/m²) and 20.8% (0.043 items/m²).
显示更多 [+] 显示较少 [-]A changing estuary: Understanding historical patterns in salinity and fecal coliform levels in the May River, SC
2021
Soueidan, Jamileh | Warren, Alan | Pearson, Mike | Montie, Eric W.
The May River, South Carolina watershed has undergone rapid increases in population and development from 1999 to 2017. This study aimed to understand the factors that influence salinity and fecal coliform levels in this estuary and how these levels changed from 1999 to 2017. This analysis revealed that salinity levels decreased in the headwaters, while variability increased. Additionally, fecal coliform increased from 1999 to 2017 throughout the hydrological network, with drastic changes occurring in the headwaters. Salinity and fecal coliform were influenced by spatial (distance from the mouth of the river), temporal (year, season, and tidal cycles), environmental (El Niño Southern Oscillation and rainfall), and anthropogenic parameters (population). This analysis suggests that the synergistic nature of climate change, resulting in more intense and frequent El Niño events, and watershed development may lead to further decreases in salinity and increases in fecal coliform levels in the May River estuary.
显示更多 [+] 显示较少 [-]Risk assessment of marine invasive species in Chinese ports introduced by the global shipping network
2021
Wan, Zheng | Shi, Zhuangfei | Nie, Anwei | Chen, Jihong | Wang, Zhaojun
The discharge of ballast water from ocean-going ships is a major pathway by which invasive species are introduced into coastal waters. As a global factory and trade power with extensive shipping networks, China has paid a huge ecological price for its progress. However, current endeavors to protect the nation's biodiversity are largely focused on terrestrial ecosystems. Therefore, for the first time, we conducted a comprehensive risk assessment of ballast water-induced biological invasion in Chinese ports. The results showed that the ports in the Yangtze River Delta, Pearl River Delta, and Southern Taiwan Province face significantly high invasion risks, and the number of donor ports, connected ships, and arriving vessels showed a positive correlation with the invasion risk. Further, we observed that even a low efficacy disinfection of ballast water can still significantly decrease the level of invasion risk.
显示更多 [+] 显示较少 [-]Development a new index for littered waste assessment in different environments: A study on coastal and urban areas of northern Iran (Caspian Sea)
2021
Jonidi Jafari, Ahmad | Latifi, Parvaneh | Kazemi, Zohre | Kazemi, Zahra | Morovati, Maryam | Farzadkia, Mahdi | Torkashvand, Javad
The coastal pollution has been evaluated using indexes like Clean Coast Index (CCI) in many countries. In this study, several coasts and urban areas in northern of Iran along the Caspian Sea, were assessed in terms of number and composition of litters. Furthermore, Clean Environment Index (CEI) was used for the first time to interpret the results. The results indicated that 60% of the coasts and 50% of the urban areas were in a dirty status and only 22% of the total surveyed areas were found to be in a clean status. The highest number of litters observed in the study areas was cigarette butt. Due to the impact of risk factor of different types of littered waste, it was obviously clear that CEI offers a more realistic and rigorous interpretation than CCI. Therefore, this new index can be considered to evaluate litters pollution in various areas.
显示更多 [+] 显示较少 [-]Acute and chronic effects of innovative antifouling nanostructured biocides on a tropical marine microcrustacean
2021
Jesus, Édipo Paixão Silva de | Figueirêdo, Lívia Pitombeira de | Maia, Frederico | Martins, Roberto Borges | Nilin, Jeamylle
This study aimed to investigate the toxicity of innovative antifouling nanostructured biocides DCOIT and silver associated to silica nanocapsules (SiNC) on the tropical microcrustacean Mysidopsis juniae. The toxicity of the tested compounds can be summarized as follows (acute tests): DCOIT > SiNC-Ag > SiNC-DCOIT > SiNC-DCOIT-Ag > SiNC > Ag; (chronic tests): SiNC-Ag > SiNC-DCOIT-Ag > DCOIT > Ag > SiNC, although it was not possible to determine the chronic toxicity of SiNC-DCOIT. In general, our data demonstrated that mysids were more sensitive than most temperate species, and it was possible to conclude that the combination SiNC-DCOIT-Ag showed less acute toxicity in comparison to the isolated active compounds, reinforcing data obtained for species from temperate environments on the potential use of nanomaterial to reduce toxicity to non-target species. However, despite representing less risk to the environment, the compound SiNC-DCOIT-Ag is still very toxic to the non-target tropical mysid.
显示更多 [+] 显示较少 [-]Spatiotemporal variability of solid waste on sandy beaches with different access restrictions
2021
Abude, Rayane R.S. | Augusto, Matheus | Cardoso, Ricardo S. | Cabrini, Tatiana M.B.
Intense human use and high construction density in coastal areas are stressors to sandy beaches. Pollution by marine debris is a major problem on beaches worldwide. This study pioneered an assessment of marine debris characterization over time on beaches with different levels of access. In two periods and seasons, marine debris was sampled on nine sandy beaches of Rio de Janeiro, grouped by levels of access. The general marine debris density has decreased over time, accompanied by an improvement in public cleaning mechanisms. The most important predictor for the majority of marine debris items is related to accessibility; beaches with restricted access showed a reduction in the abundance of most items. High marine debris densities, even on beaches with restricted access, showed that all evaluated beaches can be sinks for marine debris circulating in marine waters. Beach cleaning strategy improvements will be inefficient unless integrated marine debris management is implemented.
显示更多 [+] 显示较少 [-]Analysis of emissions and residue from methods to improve efficiency of at-sea, in situ oil spill burns
2021
Aurell, Johanna | Holder, Amara | Gullett, Brian | Lamie, Nathan | Arsava, Kemal | Conmy, Robyn | Sundaravadivelu, Devi | Mitchell, William | Stone, Karen
The combustion efficiency of simulated at-sea surface oil burns (in situ burns) was determined in a 63 m³ tank while testing varied boom configurations and air-assist nozzles in the presence and absence of waves. Combustion efficiencies of Alaska North Slope oil based on unburned carbon in the plume emissions ranged from 85% to 93% while values based on oil mass loss ranged from 89% to 99%. A four-fold variation in PM₂.₅ emission factors was observed from the test conditions. The most effective burns in terms of reduced emissions and post-burn residue concentration of total petroleum hydrocarbons were those that had high length to width boom ratios resulting in higher flame front surface area exposure to ambient air. The amount of oil mass lost was not related to any combustion efficiency parameters measured in the plume, representing a potential tradeoff between unburnt oil and air pollution.
显示更多 [+] 显示较少 [-]Dietary intake of trace elements from commercially important fish and shellfish of Thoothukudi along the southeast coast of India and implications for human health risk assessment
2021
Shalini, Rajendran | Jeyasekaran, Geevaretnam | Shakila, Robinson Jeya | Sundhar, Shanmugam | Arisekar, Ulaganathan | Jawahar, Paulraj | Aanand, Samraj | Sivaraman, Balasubramanian | Malini, Asha Hema | Surya, Tamizhselvan
The concentrations of eight trace elements (chromium, cobalt, copper, zinc, arsenic, cadmium, mercury and lead) in14 commercially important fish and shellfish collected from Thoothukudi along the southeast coast of India was investigated using inductively coupled plasma mass spectrometry in order to assess the health risks associated with their consumption. The concentration of trace elements ranged from 0.001 to 39.5 μg/g. The estimated weekly intake of cadmium in seven fish and shellfish (0.0081–0.0996 mg/kg body weight) were above the provisional tolerable weekly intake set by the Joint FAO/WHO Expert Committee on Food Additives. The risk assessment analysis indicated that there was non- carcinogenic risk upon lifetime consumption of rock crab, C. natator (TTHQ >1) and carcinogenic risks upon lifetime consumption of S. jello, P. semisulcatus, P. sanguinolentus C. natator, Uroteuthis duvaceli, Sepia pharaonis and Cistopus indicus due to cadmium exposure indicating a potential health risk to the exposed consumers.
显示更多 [+] 显示较少 [-]Baseline concentrations of pharmaceuticals in Kuwait's coastal marine environment
2021
Gevao, Bondi | Uddin, Saif | duPont, Sam
This study was carried out to provide baseline information on the concentrations of pharmaceuticals in Kuwait's coastal waters. Samples were collected over four sampling campaigns from various outfalls that occasionally discharged water into the marine environment and analyzed for a range of pharmaceuticals including analgesic/anti-inflammatories, antibiotics, anticoagulant, antidiabetic, antihelmintics, antihypertensives, antiplatelet agent, asthma medication, β-blocking agent, calcium channel blocker, diuretic, histamine H1 and H2 receptor antagonist, lipid regulators/cholesterol-lowering, prostatic hyperplasia, psychiatric drug, sedation and muscle relaxant, synthetic glucocorticoid, tranquilizer and x-ray contrast media. The levels varied between the detection limits of the method and a maximum of 28,183 ng/L for analgesics/anti-inflammatories. The highest pharmaceutical concentrations were in samples collected during the September campaign, possibly linked to the increased prescription of these medications to treat infectious diseases and flu prevalent in Kuwait during the winter months. The spatial variation is concentration is evident with KISR site being most polluted as hospital wastewater is discharged at the site. This study provides the first dataset on the concentrations of pharmaceuticals in the seawater in Kuwait and possibly the wider Arabian Gulf. Kuwait's coastal water pharmaceutical concentrations derived from this study exceed those reported from the Spanish coast, the Hong Kong harbour, the Bohai and the Yellow seas. More studies are needed to evaluate the environmental impact that these residues may have on non-target organisms.
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