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Analysis of optical and physical properties of aerosols during crop residue burning event of October 2010 over Lahore, Pakistan Полный текст
2015
Tariq, Salman | ul-Haq, Zia | ʻAlī, Muḥammad
Aerosols released from biomass burning affect the tropospheric chemistry, radiation budget and cloud processes and hence can cause significant climate modifications. Due to certain economical reasons, the open burning of crop residue has become popular in Pakistan. In the present work we have analyzed the optical and physical properties of aerosols during crop residue burning over Lahore, a central location of Pakistan. The data from ground based Aerosol Robotic Network (AERONET), satellite based MODIS and CALIPSO remote sensing instruments have been used for the characterization of aerosols during crop residue burning event of October 2010. The maximum value (2.75) of daily mean AOD was observed on 20 October 2010 and the next highest value of 2.64 was observed on 19 October 2010, indicating heavy aerosol loading over Lahore on both days due to intense crop residue burning. The fine mode AOD values ranged from 0.14 to 2.68 (on 20 October 2010) with average value of 0.87 during October 2010 over Lahore. It was found that fine mode aerosols have greater contribution than coarse mode aerosols towards total aerosol burden indicating the presence of fine mode (crop residue burning) aerosols over Lahore. Cluster analysis showed that the mixed aerosols (biomass burning and urban-industrial) were present during the heavy aerosol loading period over Lahore. The highest volume concentration of fine mode occurred on 19 and 20 October 2010 representing the dominance of fine mode aerosols. Due to scattering of incoming solar radiation by intense smoke observed on 19 and 20 October 2010 high values of SSA (∼0.95) were found. HYSPLIT model backward trajectories showed that the winds transported aerosols from southeast and northwest directions.
Показать больше [+] Меньше [-]Characterization of the size-segregated inorganic compounds in Lin'an, a Regional Atmosphere Background Station in the Yangtze River Delta region Полный текст
2015
Li, Xingru | Zhang, Ruiying | Cong, Xiaoguang | Cheng, Linglong | Liu, Jie | Xu, Honghui
PM1.0 and PM2.5 samples are collected in Lin'an, a Regional Atmosphere Background Station in spring (1–30 April), summer (1–31 July), autumn (1–31 October) and winter (1–31 January) in 2011 to investigate the seasonal characteristics of aerosol pollution in the Yangtze River Delta region. The daily concentrations of water-soluble ions are 24.6 ± 12.0 μg m−3 and 36.6 ± 23.6 μg m−3 in PM1.0 and PM2.5, respectively. SO42−, NO3− and NH4+ are the dominant contributors of water-soluble ions, accounting for 78.6% (spring), 83.5% (summer), 80.6% (autumn) and 81.9% (winter) of the total ions measured in PM1.0 and 80.2% (spring), 85.4% (summer), 78.9% (autumn) and 78.9% (winter) in PM2.5. Seasonal variation is observed, with the lowest ions concentration in winter and the highest one in summer. Nevertheless, the crustal elements (e.g., Ca, Mg, Al, Fe, etc.) have the highest concentrations in spring. Most of the pollution species (Sb, Se, Cd, Pb, As and Zn) have enrichment factor values higher than 100, implying a strong possibility that the air pollution originates from anthropogenic sources and have no evident seasonal variation. The high concentration of K+ and biomass burning potassium (K+BB) in PM2.5 in autumn and winter and its good correlation with black carbon (r = 0.74) suggest that the most severe pollution derives from biomass burning. Factor analysis results indicate that road dust, combustion processes (biomass burning and fossil fuels combustion), sea salt from marine sources and industrial activities are main sources of aerosol pollution in Lin'an.
Показать больше [+] Меньше [-]Indoor air quality assessment in painting and printmaking department of a fine arts faculty building Полный текст
2015
Can, Emre | Özden Üzmez, Özlem | Döğeroğlu, Tuncay | Gaga, Eftade O.
Measurements for indoor air quality assessment were carried out in Painting and Printmaking Department of Anadolu University Faculty of Fine Arts in Turkey. Concentrations of nitrogen dioxide (NO2), ozone (O3) and 29 Volatile Organic Compounds (VOCs) were measured simultaneously by using diffusive samplers. Simultaneous outdoor measurements were also performed at some sampling points. Analyses of NO2 and ozone samples were performed by using ion chromatography and VOCs were analyzed by using gas chromatography-mass spectrometry. Indoor NO2 and ozone concentrations varied between 13.47–89.77 μg m−3 and 3.89–51.82 μg m−3, respectively. Average indoor NO2 concentration was obtained as 35.37 ± 10.9 μg m−3. Indoor/outdoor NO2 ratio (I/O) was found as 1.44 ± 0.4 which indicated the presence of some indoor sources. Average indoor ozone concentration was 9.97 ± 4.4 μg m−3 and I/O ratio was obtained lower than 1 (0.46 ± 0.4). The highest VOC concentrations were observed at workshops where oil painting and stained glass studies were performed. Especially, the concentrations obtained from the stained glass workshop (benzene: 3.98 ± 1.3 μg m−3, toluene: 999.33 ± 104.2 μg m−3, ethly benzene: 66.06 ± 16.1 μg m−3, m,p xylene: 129.44 ± 33.1 μg m−3, o-xylene: 76.14 ± 23.1 μg m−3) were much higher than the other sampling points. Toluene concentrations exceeded the WHO (World Health Organization) limit value (260 μg m−3 weekly average) at 40% of the sampling points. Cancer risks were estimated by using the personal exposure concentrations. Lifetime cancer risks for the people working in the department such as faculty members and technicians were obtained higher than USEPA acceptable risk value (1 × 10−6) while the risks for the students were below this value.
Показать больше [+] Меньше [-]Repeated rapid assessment surveys reveal contrasting trends in occupancy of marinas by non-indigenous species on opposite sides of the western English Channel Полный текст
2015
Bishop, John D.D. | Wood, Christine A. | Lévêque, Laurent | Yunnie, Anna L.E. | Viard, Frédérique
Rapid assessment surveys of non-indigenous species (NIS) of sessile invertebrates were made at seven marinas in NW France and 10 marinas in SW England in 2010, and repeated in 2013. Fourteen NIS were recorded, 12 of which were seen on both coasts. Site occupancy differed between the opposite sides of the western English Channel. In Brittany, most species occurred at most sites in both 2010 and 2013. In 2010, site occupancy in Devon & Cornwall was distinctly lower; by 2013, the difference compared to Brittany had narrowed considerably, largely because of rapid colonisation of additional sites by species that were infrequent in 2010. Three more of the recent NIS are present in Devon & Cornwall but have still not become widespread. It is concluded that the recently introduced fouling animals studied here are longer established in NW France than in SW England, and have probably spread northwards across the Channel.
Показать больше [+] Меньше [-]Characterization of spatial and temporal variability in hydrochemistry of Johor Straits, Malaysia Полный текст
2015
Abdullah, Pauzi | Sharifah Mastura, | Jaafar, Othman | Mastura Mahmud, | Khalik, Wan Mohd Afiq Wan Mohd
Characterization of hydrochemistry changes in Johor Straits within 5years of monitoring works was successfully carried out. Water quality data sets (27 stations and 19 parameters) collected in this area were interpreted subject to multivariate statistical analysis. Cluster analysis grouped all the stations into four clusters ((Dlink/Dmax)×100<90) and two clusters ((Dlink/Dmax)×100<80) for site and period similarities. Principal component analysis rendered six significant components (eigenvalue>1) that explained 82.6% of the total variance of the data set. Classification matrix of discriminant analysis assigned 88.9–92.6% and 83.3–100% correctness in spatial and temporal variability, respectively. Times series analysis then confirmed that only four parameters were not significant over time change. Therefore, it is imperative that the environmental impact of reclamation and dredging works, municipal or industrial discharge, marine aquaculture and shipping activities in this area be effectively controlled and managed.
Показать больше [+] Меньше [-]Towards adaptive management of the natural capital: Disentangling trade-offs among marine activities and seagrass meadows Полный текст
2015
Bas Ventín, Leticia | de Souza Troncoso, Jesús | Villasante, Sebastián
This paper investigates the ecological, social and institutional dimensions of the synergies and trade-offs between seagrasses and human activities operating in the Natura 2000 protected site of San Simón Bay (Galicia, NW Spain). By means of a multidisciplinary approach that brings together the development of a biological inventory combined with participatory mapping processes we get key spatial and contextual understanding regarding how, where and why marine users interact with seagrasses and how seagrasses are considered in policy making. The results highlight the fisheries' reliance on seagrass meadows and the controversial links with shellfisheries. The study also reveals unresolved conflicts among those management plans that promote the protection of natural values and those responsible for the exploitation of marine resources. We conclude that the adoption of pre-planning bottom-up participatory processes is crucial for the design of realistic strategies where both seagrasses and human activities were considered as a couple system.
Показать больше [+] Меньше [-]Environmental risk assessments and spatial variations of polycyclic aromatic hydrocarbons in surface sediments in Yangtze River Estuary, China Полный текст
2015
Yu, Wenwen | Liu, Ruimin | Xu, Fei | Shen, Zhenyao
In this study, based on sampling data from 30 sites in August 2010, the environmental risks associated with 16 priority PAHs were estimated in surface sediments from the Yangtze River Estuary (YRE). The results indicated that the toxic equivalent quantities of the benzo[a]pyrene (TEQBap) from 30 sites were in the range of 1.93–75.88ngg−1, and the low-molecular-weight PAHs were the dominated species with higher potential toxicity. The results of the Incremental Lifetime Cancer Risk (ILCR) model indicated that the ILCR values of dermal contact were higher than 10−6 in the northeast region, suggesting that there were significant potential carcinogenic health risks for fishermen exposure to sedimentary PAHs via dermal contact in these areas. RQ values of PAHs indicated the various distributions of ecological risk levels in the study area. These variations might be caused by the natural and anthropogenic inputs and currents in the YRE.
Показать больше [+] Меньше [-]Informing Marine Spatial Planning (MSP) with numerical modelling: A case-study on shellfish aquaculture in Malpeque Bay (Eastern Canada) Полный текст
2015
Filgueira, Ramón | Guyondet, T. | Bacher, Cédric | Comeau, Luc A.
Informing Marine Spatial Planning (MSP) with numerical modelling: A case-study on shellfish aquaculture in Malpeque Bay (Eastern Canada) Полный текст
2015
Filgueira, Ramón | Guyondet, T. | Bacher, Cédric | Comeau, Luc A.
A moratorium on further bivalve leasing was established in 1999–2000 in Prince Edward Island (Canada). Recently, a marine spatial planning process was initiated explore potential mussel culture expansion in Malpeque Bay. This study focuses on the effects of a projected expansion scenario on productivity of existing leases and available suspended food resources. The aim is to provide a robust scientific assessment using available datasets and three modelling approaches ranging in complexity: (1) a connectivity analysis among culture areas; (2) a scenario analysis of organic seston dynamics based on a simplified biogeochemical model; and (3) a scenario analysis of phytoplankton dynamics based on an ecosystem model. These complementary approaches suggest (1) new leases can affect existing culture both through direct connectivity and through bay-scale effects driven by the overall increase in mussel biomass, and (2) a net reduction of phytoplankton within the bounds of its natural variation in the area.
Показать больше [+] Меньше [-]Informing Marine Spatial Planning (MSP) with numerical modelling: A case-study on shellfish aquaculture in Malpeque Bay (Eastern Canada) Полный текст
2015
Filgueira, Ramon | Guyondet, Thomas | Bacher, Cedric | Comeau, Luc A.
A moratorium on further bivalve leasing was established in 1999–2000 in Prince Edward Island (Canada). Recently, a marine spatial planning process was initiated explore potential mussel culture expansion in Malpeque Bay. This study focuses on the effects of a projected expansion scenario on productivity of existing leases and available suspended food resources. The aim is to provide a robust scientific assessment using available datasets and three modelling approaches ranging in complexity: (1) a connectivity analysis among culture areas; (2) a scenario analysis of organic seston dynamics based on a simplified biogeochemical model; and (3) a scenario analysis of phytoplankton dynamics based on an ecosystem model. These complementary approaches suggest (1) new leases can affect existing culture both through direct connectivity and through bay-scale effects driven by the overall increase in mussel biomass, and (2) a net reduction of phytoplankton within the bounds of its natural variation in the area.
Показать больше [+] Меньше [-]Impacts of Deepwater Horizon oil and associated dispersant on early development of the Eastern oyster Crassostrea virginica Полный текст
2015
Vignier, J. | Donaghy, L. | Soudant, P. | Chu, F.L.E. | Morris, J.M. | Carney, M.W. | Lay, C. | Krasnec, M. | Robert, R. | Volety, A.K.
Impacts of Deepwater Horizon oil and associated dispersant on early development of the Eastern oyster Crassostrea virginica Полный текст
2015
Vignier, J. | Donaghy, L. | Soudant, P. | Chu, F.L.E. | Morris, J.M. | Carney, M.W. | Lay, C. | Krasnec, M. | Robert, R. | Volety, A.K.
The explosion of the Deepwater Horizon (DWH) oil platform resulted in large amounts of crude oil and dispersant Corexit 9500A® released into the Gulf of Mexico and coincided with the spawning season of the oyster, Crassostrea virginica. The effects of exposing gametes and embryos of C. virginica to dispersant alone (Corexit), mechanically (HEWAF) and chemically dispersed (CEWAF) DWH oil were evaluated. Fertilization success and the morphological development, growth, and survival of larvae were assessed. Gamete exposure reduced fertilization (HEWAF: EC201h=1650μg tPAH50L−1; CEWAF: EC201h=19.4μg tPAH50L−1; Corexit: EC201h=6.9mgL−1). CEWAF and Corexit showed a similar toxicity on early life stages at equivalent nominal concentrations. Oysters exposed from gametes to CEWAF and Corexit experienced more deleterious effects than oysters exposed from embryos. Results suggest the presence of oil and dispersant during oyster spawning season may interfere with larval development and subsequent recruitment.
Показать больше [+] Меньше [-]Impacts of Deepwater Horizon oil and associated dispersant on early development of the Eastern oyster Crassostrea virginica Полный текст
2015
Vignier, J. | Donaghy, L. | Soudant, P. | Chu, F. L. E. | Morris, J. M. | Carney, M. W. | Lay, C. | Krasnec, M. | Robert, Rene | Volety, A. K.
The explosion of the Deepwater Horizon (DWH) oil platform resulted in large amounts of crude oil and dispersant Corexit 9500A® released into the Gulf of Mexico and coincided with the spawning season of the oyster, Crassostrea virginica. The effects of exposing gametes and embryos of C. virginica to dispersant alone (Corexit), mechanically (HEWAF) and chemically dispersed (CEWAF) DWH oil were evaluated. Fertilization success and the morphological development, growth, and survival of larvae were assessed. Gamete exposure reduced fertilization (HEWAF: EC201 h = 1650 μg tPAH50 L− 1; CEWAF: EC201 h = 19.4 μg tPAH50 L− 1; Corexit: EC201 h = 6.9 mg L− 1). CEWAF and Corexit showed a similar toxicity on early life stages at equivalent nominal concentrations. Oysters exposed from gametes to CEWAF and Corexit experienced more deleterious effects than oysters exposed from embryos. Results suggest the presence of oil and dispersant during oyster spawning season may interfere with larval development and subsequent recruitment.
Показать больше [+] Меньше [-]Underwater noise assessment in the Gulf of Trieste (Northern Adriatic Sea, Italy) using an MSFD approach Полный текст
2015
Codarin, Antonio | Picciulin, Marta
In the marine environment, underwater noise is one of the most widespread input of man-made energy. Recently, the European Commission has stressed the necessity of establishing threshold levels as a target for the descriptor 11.2.1 “Continuous low frequency sounds” in the Marine Strategy Framework Directive (MSFD). In 2012, a monthly underwater noise monitoring programme was conducted in the Gulf of Trieste (Northern Adriatic Sea, Italy); the collected acoustic samples (frequency range: 10–20,000Hz) were analysed in the 1/3 octave bands. The stations have been further clustered following the 63 and 125Hz bands noise levels. Average SPL levels resulted similar to those previously computed for proximate areas, indicating that the Adriatic Sea sub-region experiences high noise pressure in the marine waters. In its turn this claims for a scientific and technical international cooperation, as requested by the EU programme. No seasonal variation in local noise levels has been found.
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