细化搜索
结果 1531-1540 的 4,938
Potential interaction between plastic litter and green turtle Chelonia mydas during nesting in an extremely polluted beach 全文
2019
Gündoğdu, Sedat | Yeşilyurt, İrem Nur | Erbaş, Celal
This study examines the extent of macroplastic pollution on Samandağ beach and the potential effects on green sea turtles during nesting. For this purpose, a total of 39 different turtle tracks were studied. Mean plastic concentration was found to be 19.5 ± 1.2 pcs m−2. Among the different types of crawling, the highest concentrations of plastics were found on the tracks of turtles that did not attempt to dig nests (25.9 ± 8.4 pcs m−2). In total, 7 different types of plastics (disposable, film, fishing-related, foam, fragments, miscellaneous, and textile) were found, with film-type plastics being the most prevalent (11 pcs m−2). Samandağ beach was found to be greatly more polluted than any other beach in the Mediterranean Sea. We concluded that this pollution can cause negative effects, especially entanglement and entrapment, on green sea turtle females and hatchlings.
显示更多 [+] 显示较少 [-]Inorganic nutrients have a significant, but minimal, impact on a coastal microbial community's response to fresh diluted bitumen 全文
2019
Ortmann, Alice C. | Cobanli, Susan E. | Wohlgeschaffen, Gary | Thamer, Peter | McIntyre, Claire | Mason, Jennifer | King, Thomas L.
Microbes capable of degrading hydrocarbons in oil are present in low abundances in coastal waters, but quickly respond to oil following a spill. When estimating potential biodegradation rates in the laboratory, high concentrations of inorganic nutrients are often added to prevent nutrient limitation. In this study, we tested the short term response of coastal microbes to fresh diluted bitumen under varying nutrient conditions in a cold water regime. Total hydrocarbon concentrations changed minimally over five days; however, oil composition changed over time and the abundance of microbes increased in all treatments. Addition of phosphate, with or without nitrogen, resulted in rapid changes in community composition, but after three days treatments no longer differed. Nutrients were never depleted in any treatment suggesting that, even at low inorganic nutrient concentrations, microbial communities can quickly respond to hydrocarbons following a spill.
显示更多 [+] 显示较少 [-]Effects of the installation of offshore pipelines on macrozoobenthic communities (northern and central Adriatic Sea) 全文
2019
Spagnolo, A. | Cuicchi, C. | De Biasi, A.M. | Ferrà, C. | Montagnini, L. | Punzo, E. | Salvalaggio, V. | Santelli, A. | Strafella, P. | Fabi, G.
Macrozoobenthos living around several pipelines placed at different depths and sediment types in the Western Adriatic Sea was investigated for three years after structures' deployment to detect possible effects due to their installation and presence. Three environmental habitats were considered based on the grain size (silty clay, clayey silt and sand). Samplings were taken within a radius of 100 m from the pipelines and at control sites. Multivariate and univariate analysis showed peculiarities of the three habitats due to the different sediment type, without differences between pipelines and controls inside each group. Silty clay and clayey silt communities appeared quite similar, being mainly represented by opportunistic species typical of the Adriatic coastal area. Benthic populations found at the offshore relict sand were characterized by a higher percentage of sensitive species. Independently of sediment typology, pipelines' installation seems to not affect the benthic populations that appear more influenced by environmental features.
显示更多 [+] 显示较少 [-]Bioaccumulation and heavy metal concentration in tissues of some commercial fishes from the Meghna River Estuary in Bangladesh and human health implications 全文
2019
Ahmed, A.S Shafiuddin | Moshiur Rahman, | Sultana, Sharmin | Babu, S.M Omar Faruque | Sarker, Md Shafiqul Islam
Despite the beneficial aspect of aquatic food's consumption, bioaccumulation of toxic metals in fish can enhance the health risk for the consumers. Heavy metals were measured from editable tissues of some commercial fish species like Latis calcarifer, Silonia silondia, Clupisoma garua, Planiliza subviridis, Otolithoides pama, Tenulosa ilisa, Rhinomugil corsula, and Aila coila in the Meghna river estuary in Noakhali district. Heavy metals such as As, Pb, Cd, Cu, and Cr were detected by ICP-MS, which were significantly different (p ≤ 0.01), and the hierarchy of all mean concentrations were: Cu (5.14 mg/kg) > Pb (3.79 mg/kg) > As (1.08 mg/kg) > Cr (0.78 mg/kg) > Cd (0.12 mg/kg). The mean concentration of Cu (6.62 mg/kg) imparted to the maximum level in L. calcarifer, which slightly exceeded the Bangladesh food safety guideline. The mean BAFs of the contaminants were found as: Pb (1042.29) > Cr (1036.47) > As (934.84) > Cd (832.77) > Cu (772). Further, L. calcarifer, S. silondia, C. garua, and P. subviridis showed the bioaccumulative status. To assess the health risk effects, estimated daily intake (EDI), target hazard quotient (THQ) and carcinogenic risk (CR) were conducted. THQs for both adult and children consumers were <1, indicating that, consumers would not experience the non-carcinogenic health effects. Although children were more susceptible than adults, CR for all the consumers was found in the acceptable range (10⁻⁶ to 10⁻⁴).
显示更多 [+] 显示较少 [-]The chemical behaviors of microplastics in marine environment: A review 全文
2019
Guo, Xuan | Wang, Jianlong
Microplastics are widely existed in marine and coastal environments, which aroused global concern in recent years. This review mainly summarized the interactions of organic pollutants and metals with microplastics based on environmental monitoring results and laboratory results reported by literatures. Firstly, the type, properties, and distribution of microplastics in the environment were briefly reviewed. Secondly, the property changes of microplastics after degradation were discussed. Thirdly, the concentrations of pollutants on microplastics in global environments were summarized. Then the effect of the factors (e.g. types and properties of microplastics, types of pollutants, and environmental conditions) on the sorption behaviors of microplastics were discussed in detail. Finally, the influences of microplastics on marine organisms were briefly evaluated.
显示更多 [+] 显示较少 [-]Health Effects of Climate Change Through Temperature and Air Pollution 全文
2019
Lou, Jianing | Wu, Yangyang | Liu, Penghui | Kota, Sri Harsha | Huang, Lei
PURPOSE OF REVIEW: Recognizing health effects of changes in temperature caused by climate change and changes in air pollution affected by temperature changes on human health, predicting the health effects of both future temperature changes and air quality changes caused by climate change is critical to adopting a range of measures to respond to future climate change. The purpose of this review is to summarize studies on the health effects of temperature and air quality changes affected by climate change directly or indirectly, and to summarize the limitations of these studies. RECENT FINDINGS: After summarizing the main methods and results, we conclude that past temperature changes and air pollution caused by climate change directly or indirectly have a serious impact on the mortality or morbidity of human diseases, and climate change does impact human health and will exacerbate these effects. Moreover, it may have spatial and socioeconomic differences in the world. Nonetheless, these studies also indicate that policies about climate change and emission reduction can reduce these effects. The evaluation focuses on the interaction between temperature change and air quality caused by climate change and assesses the impact of both on human health. There are still some uncertainties in existing research, and future health predictions related to climate change should focus on quantitative exploration of temperature and air pollution changes, eliminate interference caused by factors such as industrialization, and demographic changes, while the choice of meteorological conditions should be further extended, not just limited to the temperature and air quality.
显示更多 [+] 显示较少 [-]A feedback-controlling digital microfluidic fluorimetric sensor device for simple and rapid detection of mercury (II) in costal seawater 全文
2019
Zhang, Qian | Zhang, Xingcai | Zhang, Xiaolin | Jiang, Lan | Yin, Jingmei | Zhang, Peng | Han, Shuang | Wang, Yunhua | Zheng, Guoxia
By combination of miniaturization potential of digital microfluidics (DMF) and sensitivity of fluorescence probe, an integrated sensor device has been initially constructed for mercury detection in coastal waters. The actuation feature of the detecting target, seawater droplet, which remains unclear, was basically explored. To overcome a potential risk of driven failure, induced by diversity ion ingredients in seawater, a feedback control loop was included into control system. Analyzing method for coastal waters was well established on DMF, which showed satisfied stability and selectivity in Hg sensing under high salinity condition, with the sensitivity of Hg²⁺ at the parts per billion level and total testing time less than 20s. With the advantages of being fast, amenable to automation and low cost, this device is promising for the formation of simple and rapid sensor device, especially for a routine monitoring and emergency detection of Hg/or other metals in coastal waters.
显示更多 [+] 显示较少 [-]Spatial trends and drivers of marine debris accumulation on shorelines in South Eleuthera, The Bahamas using citizen science 全文
2019
Ambrose, Kristal K. | Box, Carolynn | Boxall, James | Brooks, Annabelle | Eriksen, Marcus | Fabres, Joan | Fylakis, Georgios | Walker, Tony R.
This study measured spatial distribution of marine debris stranded on beaches in South Eleuthera, The Bahamas. Citizen science, fetch modeling, relative exposure index and predictive mapping were used to determine marine debris source and abundance. Citizen scientists quantified debris type and abundance on 16 beaches within three coastal exposures (The Atlantic Ocean, Great Bahama Bank and The Exuma Sound) in South Eleuthera. Marine debris, (~2.5 cm or larger) on each beach was monitored twice between March–May and September–November 2013 at the same locations using GPS. Approximately, 93% of all debris items were plastic with plastic fragments (≤2.5 cm) being the most common. There were spatial differences (p ≤ 0.0001) in plastic debris abundance between coastal exposures. Atlantic Ocean beaches had larger quantities of plastic debris by weight and by meter (m) of shoreline. Stranded plastic may be associated with Atlantic Ocean currents associated with leakage from the North Atlantic sub-tropical gyre.
显示更多 [+] 显示较少 [-]Baseline evaluation of metal contamination in teleost fishes of the Gulf of Tigullio (north-western Italy): Histopathology and chemical analysis 全文
2019
Reboa, Anna | Mandich, Alberta | Cutroneo, Laura | Carbone, Cristina | Malatesta, Arianna | Capello, Marco
Metals, whether essential (Cu, Zn, Cr, Fe, Mn) or non-essential (Al, As, Cd, Ni, Pb, Hg) for organism metabolism, occur naturally in the marine environment and their abundance can increase due to the presence of human activities. In this study, fish were used as bio-indicators, to determine a correlation between the bio-accumulation of metals in muscle and gill tissues and the health status of fish. The study area was the Gulf of Tigullio (north-western Italy), which is impacted by various sources of metal contamination. Histopathology served as a significant tool to investigate possible alterations in gills, one of the main organs involved in fish physiology. Results highlighted some correlations between certain metals (e.g. Pb, Ni) and gill alterations (e.g. epithelial hyperplasia, epithelial lifting), providing baseline data from a pool of different fish species, which can be used for comparison purposes in further studies.
显示更多 [+] 显示较少 [-]Assessment of the toxicity, origin, biodegradation and weathering extent of petroleum hydrocarbons in surface sediments of Pars Special Economic Energy Zone, Persian Gulf 全文
2019
Rostami, Saman | Abessi, Ozeair | Amini-Rad, Hassan
During the last years, the oil and gas explorations, extractions and refineries have led to severe ecological damages into the sensitive environment of the Persian Gulf. In this study, the level of oil contamination, the source of hydrocarbons and the degree of weathering or degradation extent were investigated in the Surface Sediments of Pars Special Zone, Persian Gulf. Fifteen sediment samples were collected. The Gas Chromatography-Mass Spectrometry used to analyze Aliphatic Hydrocarbons (AHC) and EPA's sixteen compounds of Polycyclic Aromatic Hydrocarbons (PAHs). The total concentration of Aliphatic Hydrocarbons found to be in the range of 693 to 3752 μg/g and the 16 EPA PAHs compounds varied between 46.6 and 84.7 ng/g dry weight in the region. The concentration of hydrocarbons found to be lower than the level of threshold effects. The source of compounds was also identified by developing the multiple indices.
显示更多 [+] 显示较少 [-]