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Marine litter in bottom trawls off the Portuguese coast Full text
2015
Neves, Diogo | Sobral, Paula | Pereira, Tânia
Benthic marine litter along the Portuguese coast, was recorded in 14 trips on stern trawlers covering a distance of 2117km and an area of 56.2km2, average depth range 90–349m. 2034 items of marine litter were registered, 76% were plastics and 38.6% were originated from fishing related activities. Plastic was present in all the trawls and had the highest average density of all litter categories, 50itemskm−2.The highest density of marine litter (178.9±64.0itemskm−2) was found in the proximity of the Tagus river mouth, probably related to the high population density in the Lisbon metropolitan area.This study highlights the need to raise fishermen awareness for the adoption of good environmental practices that will contribute to the reduction of marine litter.
Show more [+] Less [-]Impact of silver nanoparticles on benthic prokaryotes in heavy metal-contaminated estuarine sediments in a tropical environment Full text
2015
Antizar-Ladislao, B. | Bhattacharya, B.D. | Ray Chaudhuri, S. | Sarkar, S.K.
Little knowledge is available about the potential impact of commercial silver nanoparticles (Ag-NPs) on estuarine microbial communities. The Hugli river estuary, India, is susceptible to heavy metals pollution through boat traffic, and there is the potential for Ag-NP exposure via effluent discharged from ongoing municipal and industrial activities located in close proximity. This study investigated the effects of commercial Ag-NPs on native microbial communities in estuarine sediments collected from five stations, using terminal restriction fragment length polymorphism (T-RFLP) technique. An increase in the number of bacteria in consortium in sediments was observed following exposure to Ag-NPs. In general microbial communities may be resistant in estuarine systems to the antimicrobial effects of commercial Ag-NPs, but key microorganisms, such as Pelobacter propionicus, disappeared following exposure to Ag-NPs. In conclusion, the T-RFLP analysis indicated that Ag-NPs have the potential to shape estuarine sediment bacterial community structure.
Show more [+] Less [-]Geographic structure evidenced in the toxic dinoflagellate Alexandrium pacificum Litaker (A. catenella – group IV (Whedon & Kofoid) Balech) along Japanese and Chinese coastal waters Full text
2015
Genovesi, Benjamin | Berrebi, Patrick | Nagai, Satoshi | Reynaud, Nathalie | Wang, Jinhui | Masseret, Estelle
The intra-specific diversity and genetic structure within the Alexandrium pacificum Litaker (A. catenella – Group IV) populations along the Temperate Asian coasts, were studied among individuals isolated from Japan to China. The UPGMA dendrogram and FCA revealed the existence of 3 clusters. Assignment analysis suggested the occurrence of gene flows between the Japanese Pacific coast (cluster-1) and the Chinese Zhejiang coast (cluster-2). Human transportations are suspected to explain the lack of genetic difference between several pairs of distant Japanese samples, hardly explained by a natural dispersal mechanism. The genetic isolation of the population established in the Sea of Japan (cluster-3) suggested the existence of a strong ecological and geographical barrier. Along the Pacific coasts, the South–North current allows limited exchanges between Chinese and Japanese populations. The relationships between Temperate Asian and Mediterranean individuals suggested different scenario of large-scale dispersal mechanisms.
Show more [+] Less [-]Concentrations of carbon monoxide in indoor and outdoor air of Ghalyun cafes Full text
2015
Fazlzadeh, Mehdi | Rostami, Roohollah | Hazrati, Sadegh | Rastgu, Ali
Indoor and outdoor carbon monoxide (CO) concentrations were measured in 68 Ghalyun cafes in Ardabil City of Iran. One hour sampling was performed in each location and hourly mean concentrations were reported. Respective mean concentrations of CO in indoor and outdoor air were 24.75±17.17 and 2.65±1.33 ppm with an average indoor to outdoor air concentration ratio of 13.3±13.1. Within the variables studied; type of the tobacco smoked, location of the cafe inside the building, and utilizing mechanical ventilator, respectively, were recognized as the most influential factors controlling CO concentrations in Ghalyun cafes (p<0.05). 73.5% of workers (27.3 and 95.7% of cafes located on ground floors and basements, respectively) were exposed to higher levels of CO than the corrected OEL–TWA (Occupational Exposure Limit) of 10.4 ppm.
Show more [+] Less [-]A review of standards and guidelines set by international bodies for the parameters of indoor air quality Full text
2015
Abdul–Wahab, Sabah Ahmed | Chin Fah En, Stephen | Elkamel, Ali | Ahmadi, Lena | Yetilmezsoy, Kaan
Standards and guidelines as defined by various international agencies are employed by the researchers to evaluate an acceptable quality of air in indoor as well as outdoor environments. The main objective of this paper is to establish a comprehensive review of Indoor Air Quality (IAQ) guidelines and other standard values that are implemented currently. For this purpose, the present study summarizes the main standards and guidelines related to key indoor air pollutants and levels of thermal comfort developed by different agencies around the world. These agencies and organizations include the American Society of Heating, Refrigerating and Air– Conditioning Engineers (ASHRAE), the Hong Kong Environmental Protection Department (HKEPD), the World Health Organization (WHO), and the National Health and Medical Research Council (NHMRC) of Australia. Common indoor air pollutants that are found to frequently affect indoor populations are, carbon dioxide (CO2), nitrogen dioxide (NO2), formaldehyde (HCHO), carbon monoxide (CO), sulfur dioxide (SO2), and particulate matter in sizes <2.5 and 10 μm (PM2.5 and PM10, respectively). Other factors that affect IAQ are the moisture content of the air (i.e., relative humidity), the temperature of the indoor air, and the air speed or movement. Sick building syndrome (SBS) describes the various interactions between these major pollutants and factors of IAQ that cause adverse health effects on humans. In addition, this paper reviews various stipulated guidelines that are implemented by the relevant regulatory institutions and agencies to prevent SBS.
Show more [+] Less [-]Temporal and spatial distribution of tropospheric NO2 over Northeast Asia using OMI data during the years 2005–2010 Full text
2015
Kim, Deok–Rae | Lee, Jae–Bum | Keun Song, Chang | Kim, Seung–Yeon | Ma, Young–ll | Lee, Kyung–Mi | Cha, Jun–Seok | Lee, Sang–Deok
This study aimed to examine the main characteristics of tropospheric nitrogen dioxide (NO2) concentrations over the Northeast Asia, using the Ozone Monitoring Instrument (OMI) data from 2005 to 2010. The annual mean NO2 concentrations (AMNC) had an increasing trend mainly due to increasing NO2 emissions in China except during the 2008 Beijing Olympic Games period, while the reduction policies of South Korea and Japan have led it to be stagnant or decreased. To investigate further regional characteristics of NO2 increasing trends in China, we divided our study area into 6 geographical regions (sectors 1–6) and then considering 4 different socio–economic levels (groups 1–4) among main cities in Eastern regions (sector 2 and 4) where the concentrations level is the highest in China and NO2 concentrations show continued increasing trend. Especially OMI NO2 and emissions consistently showed that metropolitan/big—sized and developed cities (group 1), such as Beijing and Shanghai, had an increasing trend of NO2 concentrations until 2007 and decreasing thereafter, while small/mid–sized and developing cities (groups 2 and 3) kept a continuous increasing trend over all periods. The seasonal change in NO2 concentrations showed the apparent increasing trend in winter and no significant trend in summer in all groups except for group 1. These results indicate that an increase in AMNC in Northeast Asia was mainly attributed to the increasing NO2 concentrations in winter in groups 2 and 3. Therefore, it strongly suggests the importance of the NO2 management for groups 2 and 3 to improve air quality in the Northeast Asia.
Show more [+] Less [-]Human impact on atmospheric precipitation in a protected area in Western Poland. Results of long–term observations: Concentrations, deposition and trends Full text
2015
Walna, Barbara
The paper presents the results of long–term measurements of rain chemistry in the woodland area of the Wielkopolski National Park (Western Poland) experiencing some human impact. The ions predominating in precipitation turned out to be those of ammonium and sulfates, which is indicative of human impact related with agriculture and animal breeding as well as with SO2 emissions. In the period 2002–2013 it is possible to identify, for both precipitation and throughfall, statistically significant decreasing trends in the concentrations and deposition of sulfates, ammonium and potassium, and an increasing trend for fluoride. Both bulk deposition and throughfall of N was higher than that of S. The deposition of nitrogen with throughfall was near to the critical load. High levels of acid–forming ions were observed in both, the winter and late–spring seasons, which proves not only the impact of heating but also of the local industry. Notable is the simultaneous occurrence of extremely high levels of acid–forming ions in some precipitation events, which might have many important implications for the soil, water and biota. There was a change in the pattern of atmospheric chemistry observed as a statistically significant downward trend in the rates of ionic concentration equivalents.
Show more [+] Less [-]Evaluation of highly mobile fraction of trace elements in PM10 collected in Upper Silesia (Poland): Preliminary results Full text
2015
Zajusz-Zubek, Elwira | Mainka, Anna | Korban, Zygmunt | Pastuszka, Józef S.
The amount of the soluble fraction of trace elements released from inhaled particulate matter seems to be one of the key factors of the toxicity of these particles. This study reports the concentrations of PM10 and trace elements in total and water-soluble fractions (bioavailable form). Weekly samples were collected at two rural sites in Upper Silesia, Poland. Measurements were carried out from April to August 2013, divided between heating and non-heating sessions. During heating sessions, the concentrations of PM10 in selected sites varied in the range of 32.88–48.70 μg m−3, while for the non-heating sessions the range was 16.14–27.89 μg m−3.Selected PM10 samples (characteristic for both sessions) were determined by means of total and water-soluble content of eight trace elements. The elements are characteristic of carcinogenic (As, Cr, Cd and Ni), probably carcinogenic (Co and Pb) and toxic (Mn and Sb) groups. The analyses of the mineralized samples as well as the water-soluble fractions were carried out by ICP-MS method using a Varian 810 MS.The total concentration of carcinogenic Cd, Cr and Ni during non-heating sessions was 2.81, 7.97 and 4.82 ng m−3, respectively. While during heating sessions the total content was twice as high. Similar relation was observed for the concentration of PM10. The concentration of the soluble fraction of these elements in the atmospheric air in heating sessions was 1.62, 0.75, 2.20, 1.79, 1.85 ng m−3 for As, Cr, Pb, Mn, Sb, respectively and remained almost the same as in non-heating sessions. Lower levels of Ni and Cd (0.15 and 0.11 ng m−3) were determined during heating sessions. The obtained data indicate that during heating periods these elements are probable present mainly in other fractions with lower mobility, so less harmful to human health.
Show more [+] Less [-]Clam predator protection is effective and necessary for food production Full text
2015
Shellfish aquaculture is a widely practiced way of producing food for human consumption in coastal areas. When farming intertidal clams, farmers commonly protect young seedling clams from predatory losses by covering farmed plots with netting or screening. Recent discussion of the effectiveness of protective nets or screens and their environmental effects has raised questions concerning the utility of the practice. We provide data based on a review of more than 35 peer-reviewed articles, as well as our own research that demonstrates the efficacy of predator protection for clam farms in various habitats around the world. In addition, we evaluate the effects of screening on temperature, and comment on ancient practices of clam gardening as conducted in the Pacific Northwest.
Show more [+] Less [-]Introduction of the alien Xenostrobus securis (Bivalvia: Mytilidae) into Hong Kong, China: Interactions with and impacts upon native species and the earlier introduced Mytilopsis sallei (Bivalvia: Dreissenidae) Full text
2015
Morton, Brian | Leung, K.F.
This constitutes the first record of the Australian alien mytilid Xenostrobus securis in China. The introduction occurred prior to 2010 probably via shipping arriving at Yantian in Mirs Bay, China, close to Hong Kong. Point sources of infection could be Australia or Korea or Japan where it has similarly been introduced. Analysis of X. securis in Hong Kong shows that it tolerates a wide range of salinities from 5.4‰ to 28.7‰. Water temperatures in Hong Kong match those in its native range.In Hong Kong, X. securis co-occurs with the similarly introduced Mytilopsis sallei and a native bivalve community. The population structure of X. securis suggests a lifespan of >2years with new generations produced by conspecifics. Such a life history strategy is also exhibited by M. sallei. Now established in China, northern Asia, the Mediterranean and, most recently, the Iberian Atlantic, the invasion of other locations by X. securis seems probable.
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