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Twitter data analysis to assess the interest of citizens on the impact of marine plastic pollution النص الكامل
2021
Otero, P. | Gago, J. | Quintas, P.
Few studies have mined social media platforms to assess environmental concerns. In this study, Twitter was scraped to obtain a ~140,000 tweet dataset related specifically to marine plastic pollution. The goal is to understand what kind of users profiles are tweeting and how and when they do it. In addition, topic modelling and graph theory techniques have allowed us to identify main concerns on this topic: i) impact on wildlife, ii) microplastics/water pollution, iii) estimates/reports, iv) legislation/protection, and v) recycling/cleaning initiatives. Results reveal a scarce influence of organizations involved in research and marine environmental awareness, so some guidelines are depicted that could help to adjust their communication plans. This is relevant to engage society through reliable information, change habits and reinforce sustainable behaviour. A visualization tool has been created to analyze the results over time.
اظهر المزيد [+] اقل [-]Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in Pacific salmon from the Kamchatka Peninsula and Sakhalin Island, Northwest Pacific النص الكامل
2021
Donets, Maksim M. | Tsygankov, Vasiliy Yu | Gumovskiy, Alexandr N. | Gumovskaya, Yulia P. | Boyarova, Margarita D. | Busarova, Olesya Yu | Litvinenko, Anna V. | Khristoforova, Nadezhda K.
The purpose of the present study was to determine levels of POPs (dieldrin, endrin, HCH isomers, DDT metabolites, and PCB congeners) in organs of chum (Oncorhynchus keta), pink (O. gorbuscha), sockeye (O. nerka), masu (O. masou), and Chinook salmon (O. tshawytscha), and to identify the patterns of toxicants' distribution in organisms and the environment of the northwestern Pacific. Principal component factor analysis showed that all the salmon species typically exhibit relationships between the PCB congeners and are characterized by a similar pattern of entry of PCBs 101, 118, and 153. The OCPs levels in the organs of Pacific salmon are decreasing from 2012 to 2018, which suggests the elimination of these toxicants from the northwestern Pacific Ocean.
اظهر المزيد [+] اقل [-]Microparticles and microplastics contamination in African table salts النص الكامل
2021
Fadare, Oluniyi O. | Okoffo, Elvis D. | Olasehinde, Emmanuel F.
The presence of micro/plastic particles has been reported in various seafood products. However, information on microplastics contamination in salts from African continent is very limited. This study analysed 23 brands of table salts from 8 African countries for microplastics using microscopic/spectroscopic techniques. South Africa showed the highest microplastics concentration (0–1.33 ± 0.32 particles/kg), Nigeria, Cameroun, and Ghana (0–0.33 ± 0.38 particles/kg each); characterized as polyvinyl acetate, polypropylene, and polyethylene. Other countries have no detectable microplastics at 0.3 μm filter pore size. To our best knowledge, this is the first study to characterize micro-fibres/plastics in table salts across African countries, confirming that it is an emission source of micro-fibres/plastics into the human food chain, highlighting the overarching need to understand their effects on human health.
اظهر المزيد [+] اقل [-]Spatial and environmental characteristics of colloidal trace Cu in the surface water of the Yellow River Estuary, China النص الكامل
2021
Lu, Yuxi | Pan, Dawei | Yang, Tingting | Wang, Chenchen
Dynamic variations in chemical composition and size distribution of dissolved copper (Cu) along the river-sea interface in the Yellow River Estuary (China) were investigated. On average, ~64% and ~8% of bulk dissolved Cu (<0.45 μm) were partitioned in the <1 kDa fraction and 1–100 kDa, respectively. The other 28% were in the 100 kDa–0.45 μm colloids, which indicates that this fraction may dominate the overall morphology of colloidal Cu. The <3 kDa Cu fraction was susceptible to environmental parameters and the >3 kDa fraction was related to the behavior of dissolved organic carbon. 1–100 kDa Cu migrated more violently than >100 kDa Cu and tended to be a stable polymer, with stability increasing towards the sea. The source of <1 kDa Cu was complex and may be supplemented by the decomposition of small molecular colloids and the addition of the sediments or particles ligands.
اظهر المزيد [+] اقل [-]Variation in polymer types and abundance of microplastics from two rivers and beaches in Adelaide, South Australia النص الكامل
2021
Hayes, Anna | Kirkbride, K Paul | Leterme, Sophie C.
Microplastics are a major source of marine pollution and comprise of many recyclable polymers. For this study, we investigated the prevalence of microplastic polymers in an urban and non-urban setting and determined what type of plastic polymers was most common in these areas. This was conducted by extracting sediment and sand samples from 2 rivers and beaches in Adelaide, South Australia. The microplastics were extracted using density separation and were identified using Fourier-transform infrared spectroscopy. We found a significantly higher abundance of microplastics and variety of polymers in the sediment of the Patawalonga creek, compared to the less urbanised environment. Most of the microplastics found in the study were from recyclable products which highlight the lack of recycling practices undertaken by the inhabitants of that area.
اظهر المزيد [+] اقل [-]A Review of the Use of Psychoacoustic Indicators on Soundscape Studies النص الكامل
2021
Engel, Margret Sibylle | Fiebig, André | Pfaffenbach, Carmella | Fels, Janina
This work reviews the literature of 46 peer-reviewed papers and presents the current status on the use of psychoacoustic indicators in soundscape studies. The selection of papers for a systematic review followed the PRISMA method. Afterwards, descriptive analysis and principal component analysis (PCA) were realised. For the PCA, the following parameters extracted from the papers were analysed: psychoacoustic indicator, hypothesis, statistical units, data collection method and major findings for each investigated psychoacoustic indicator. The results show an overview of the use of psychoacoustic indicators, through main hypothesis and findings for each psychoacoustic indicator i.e. the importance of statistical units, such as percentiles, to investigate the hypothesis related to the description of auditory descriptors and perceptual attributes. Another important finding is that many papers lack the specification of computation methods limiting the comparability of study results and impeding the meta-analyses.
اظهر المزيد [+] اقل [-]The behavioural response of European seabass (Dicentrarchus labrax) to chlorinated seawater effluents النص الكامل
2021
Davis, Scott H. | Maxwell, David L. | Spence, Michael A. | Muiruri, Evalyne W. | Sheahan, Dave
Seawater chlorination is widely used for coastal, marine industries for the prevention of fouling. Using a choice chamber system, we investigated the influence of chlorinated seawater at typical concentrations occurring near chlorinated cooling water discharges, on the behaviour of juvenile seabass (Dicentrachus labrax). These studies showed that there was evidence of an effect of chlorination, with models predicting 22% fewer fish present in the chlorine dosed chamber compared to the undosed chamber in all control runs (mean number of fish in the dosed chamber in all control runs was 2.23 in comparison to 1.74 when chlorine was present). These data suggest that when food is available D. labrax will enter areas that are at mean chlorination levels of 0.04 mg l⁻¹, which are typical close to the discharge of power station cooling water but are more likely to move away once the food supply is reduced.
اظهر المزيد [+] اقل [-]Effects of reclamation methods and habitats on macrobenthic communities and ecological health in estuarine coastal wetlands النص الكامل
2021
Huang, Yinying | Li, Yiming | Chen, Qiang | Huang, Yingying | Tian, Jiangtao | Cai, Mingqi | Huang, Youhui | Jiao, Yang | Yang, Ying | Du, Xinglin | Liu, Zhiquan | Zhao, Yunlong
This study compared the community structure of macrobenthos in bare tidal areas and vegetated regions under two reclamation patterns, fully enclosed and opened reclamation, in Yangtze wetland, China. Compared with fully enclosed reclamation areas, opened reclamation areas had higher water salinity, higher number of species and abundance, and less disturbed habitat health status. Compared with bare tidal areas, vegetated regions were more suitable for the survival of macrobenthos and its habitat health status was more stable. Salinity, pH and larger soil particle diameter were positively associated with macrobenthic diversity, while total nitrogen and total phosphorus were negatively associated. Overall, compared with fully enclosed reclamation and vegetated regions, opened reclamation and bare tidal areas had less negative effects upon macrobenthic community and habitat health. Opened reclamation is preferred for wetland reclamation, and planting indigenous plants and releasing species adapted to fresh water is beneficial to the restoration of macrobenthic communities.
اظهر المزيد [+] اقل [-]Chemical control of overwintering green algae to mitigate green tide in the Yellow Sea النص الكامل
2021
Gong, Ning | Shao, Kuishuang | Shen, Kun | Gu, Yanbin | Liu, Yuan | Ye, Jinqing | Hu, Chuanming | Shen, Lingyu | Chen, Yanlong | Li, Dongwei | Fan, Jingfeng
It has been 14 years since the world's largest Ulva bloom appeared in the Yellow Sea, China in 2007. Although it is clear that the Ulva bloom originates from the culture system of Porphyra yezoensis (Nori) in the southern Yellow Sea, how to control it is still little understood. Since overwintering banks played a crucial role in the development of spring population of green algae on the cultivation ropes, here, a promising method was presented to prevent the development of Ulva bloom by the inactivation of the overwintering banks of green algae on the P. yezoensis cultivation ropes during February and early March. Chlorine dioxide, an environment-friendly disinfectant was used as algaecide with dosage of no lower than 40 mg/L at the contact time of 1 min. The overwintering green algae gradually disappeared within two weeks after the treatment. Furthermore, the growth of spring population of green algae on the cultivation ropes was effectively inhibited for at least eight weeks, which contribute to prevent the formation of floating populations during cultivation facilities collection. It was expected that the present method, if to be applied in the P. yezoensis cultivation areas in southern Yellow Sea, may mitigate the magnitude of the Ulva blooms in the Yellow Sea at a lower cost.
اظهر المزيد [+] اقل [-]Bioaccumulation of heavy metals in different trophic levels of aquatic ecosystems with fish as a bioindicator in Visakhapatnam, India النص الكامل
2021
Pragnya, M. | Ajay, B. | Kumar, S Dinesh | Byragi Reddy, T.
The concentration of 23 metals was analyzed in the tissue of nine fish species, which represents the different habitats, i.e., primary feeder, tertiary feeder, and bottom feeder in fresh and marine waters of Visakhapatnam. Scomberomorus guttatus, Upeneus vittatus, and Penaeus indicus were selected in the coastal waters; Xiphias gladius, Stolephorus indicus, and Penaeus monodon from deep sea; and Channa striata, Puntius chola, and Macrobrachium rosenbergii from freshwater were analyzed. Metals in fish were analyzed by using the Inductive Couple Plasma Mass Spectrometer (ICP-MS). The concentrations of metals in fish were within the permissible limit set by WHO, FAO apart from Chromium, Aluminum, Manganese, and Arsenic. The concentrations were highest in coastal water fish and lowest in freshwater fish. Similarly, higher concentrations were observed in bottom feeders than in other tiers.
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