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Fine scale distribution constrains cadmium accumulation rates in two geographical groups of Franciscana dolphin from Argentina Texte intégral
2013
Polizzi, P.S. | Chiodi Boudet, L.N. | Romero, M.B. | Denuncio, P.E. | Rodríguez, D.H. | Gerpe, M.S.
Franciscana dolphin is an endemic cetacean in the southwestern Atlantic Ocean and is classified as Vulnerable A3d by the International Union for Conservation of Nature. Cadmium accumulation was assessed in two geographic groups from Argentina; one inhabits the La Plata River estuary, a high anthropogenic impacted environment, and the other is distributed in marine coastal, with negligible pollution. Despite the environment, marine dolphins showed an increase of renal Cd concentrations since trophic independence; while in estuarine dolphins was from 6years. This is associated with dietary Argentine anchovy which was absent in the diet of estuarine dolphins, being a trophic vector of cadmium in shelf waters of Argentina. Cluster analysis also showed high levels of cd in association with the presence of anchovy in the stomach. The difference in the fine scale distribution of species influences dietary exposure to Cd and, along with other data, indicates two stocks in Argentina.
Afficher plus [+] Moins [-]High coral cover and subsequent high fish richness on mature breakwaters in Taiwan Texte intégral
2013
Wen, Colin Kuo-Chang | Chen, Kao-Song | Hsieh, Hernyi Justin | Hsu, Chia-Min | Chen, Chaolun Allen
Breakwaters are widely used in coastal development. Breakwaters can alter habitats by undermining shallow coastal ecosystems, especially coral reefs. However, recent studies indicate that mature breakwaters can have well-developed corals and coral-associated fishes. Breakwaters with colonized corals may act as surrogates of natural coral reefs against the global coral crisis. Here, we examined the composition of corals, fishes, and benthic biota/abiota between natural reefs and mature breakwaters to evaluate the possibility of breakwaters supplementing natural reefs. We found equal or higher coral cover, fish abundance, and species richness on breakwaters. Conversely, differential coral growth forms and fish assemblages on mature breakwaters suggested the irreplaceability of natural reefs. Corals and coral reef fishes on mature man-made structures, however, may improve the resistance and resilience of coral reefs. Conclusively, despite high coral cover on mature man-made structures appropriate management (e.g., marine reserves) is still necessary to sustain the coral reefs.
Afficher plus [+] Moins [-]Allocation of marine environmental carrying capacity in the Xiamen Bay Texte intégral
2013
Liao, Enhui | Jiang, Yuwu | Yan, Xiao-Hai | Chen, Zhaoyun | Wang, Jia | Zhang, Luoping
Three optimization methods are employed to allocate Marine Environmental Carrying Capacity (MECC) in the Xiamen Bay. The hydrodynamic and pollutant fields are first simulated by the Princeton Ocean Model. Taking phosphorus as an index of the water quality, the response fields are then calculated. These response fields represent the relationship between the concentration of the sea zone and the pollution sources. Finally, MECC is optimized and distributed in the Xiamen Bay by three optimization methods. The results show classical linear optimization can only maximize the satisfaction level for one of the stake holders’, e.g., dischargers or environmental protection bureau, satisfaction level. However, the fuzzy and grey fuzzy optimizations can provide a compromise, and therefore a fairer result, by incorporating the conflicting goals of all of the different stakeholders. Compared with fuzzy optimization, the grey fuzzy optimization provides a more flexible choice for the decision-makers.
Afficher plus [+] Moins [-]Dividing the common pond: Regionalizing EU ocean governance Texte intégral
2013
Maier, Nina | Markus, Till
EU ocean policies increasingly incorporate regional measures. Under the long standing Common Fisheries Policy, such measures aim at improving and reforming existing policy, either by taking into account region specific social or ecologic requirements or by establishing procedures and institutions to achieve a regional fit. By contrast, the EU’s emerging integrated Marine Environmental Policy was designed to draw heavily on regional procedural and institutional mechanisms from the outset. The developing regional measures raise the question whether they contribute to improving institutional structures governing the use and conservation of EU waters. This article analyzes the existing and future regional measures of the two policies and their varying purposes and scopes. It develops a typology for categorizing the regional aspects and examines the effects of regional measures on EU institutions and the theoretical EU integration debate.
Afficher plus [+] Moins [-]Processing of fecal sludge to fertilizer pellets using a low-cost technology in Ghana Texte intégral
2013
Nikiema, Josiane | Cofie, Olufunke | Impraim, Robert | Adamtey, N.
Processing of fecal sludge to fertilizer pellets using a low-cost technology in Ghana Texte intégral
2013
Nikiema, Josiane | Cofie, Olufunke | Impraim, Robert | Adamtey, N.
This paper describes a study that was aimed at optimizing the pelletization of fecal sludge-based fertilizers for agricultural use. The process developed is easy to implement and increases the marketability of the products while also addressing a serious health and environmental challenge. The study took place during the period 2011-2012 in Ghana. The fecal sludge, rich in nutrients and organic matter, was dried and used to produce five different fertilizers (i.e., four formulations of compost and one with gamma irradiated material). Each material was then pelletized using locally constructed machinery. Key operating parameters, such as moisture content (10-55% in mass), binder type (clay or starch) and concentration (0-10% in mass), were varied and their impacts on the characteristics of pellets (e.g., amount of fine materials generated, length distribution or stability of pellets, and pellet disintegration rate) were also followed. Given the low analyzing capabilities of developing countries, some simple analytical methods were developed and used to compare pellets produced under different conditions. The results confirmed that the addition of 3% of pregelatinized starch is recommended during pelletization of fecal sludge-based fertilizers. Applicable moisture contents were also identified per fertilizer type, and were found to comprise between 21 and 43%.
Afficher plus [+] Moins [-]Processing of fecal sludge to fertilizer pellets using a low-cost technology in Ghana Texte intégral
2013
Nikiema, Josiane | Cofie, Olufunke O. | Impraim, Robert | Adamtey, Noah
This paper describes a study that was aimed at optimizing the pelletization of fecal sludge-based fertilizers for agricultural use. The process developed is easy to implement and increases the marketability of the products while also addressing a serious health and environmental challenge. The study took place during the period 2011-2012 in Ghana. The fecal sludge, rich in nutrients and organic matter, was dried and used to produce five different fertilizers (i.e., four formulations of compost and one with gamma irradiated material). Each material was then pelletized using locally constructed machinery. Key operating parameters, such as moisture content (10-55% in mass), binder type (clay or starch) and concentration (0-10% in mass), were varied and their impacts on the characteristics of pellets (e.g., amount of fine materials generated, length distribution or stability of pellets, and pellet disintegration rate) were also followed. Given the low analyzing capabilities of developing countries, some simple analytical methods were developed and used to compare pellets produced under different conditions. The results confirmed that the addition of 3% of pregelatinized starch is recommended during pelletization of fecal sludge-based fertilizers. Applicable moisture contents were also identified per fertilizer type, and were found to comprise between 21 and 43%.
Afficher plus [+] Moins [-]Chemometric techniques in distribution, characterisation and source apportionment of polycyclic aromatic hydrocarbons (PAHS) in aquaculture sediments in Malaysia Texte intégral
2013
Retnam, Ananthy | Zakaria, Mohamad Pauzi | Juahir, Hafizan | Ahmad Zaharin Aris, | Zali, Munirah Abdul | Kasim, Mohd Fadhil
This study investigated polycyclic aromatic hydrocarbons (PAHs) pollution in surface sediments within aquaculture areas in Peninsular Malaysia using chemometric techniques, forensics and univariate methods. The samples were analysed using soxhlet extraction, silica gel column clean-up and gas chromatography mass spectrometry. The total PAH concentrations ranged from 20 to 1841ng/g with a mean of 363ng/gdw. The application of chemometric techniques enabled clustering and discrimination of the aquaculture sediments into four groups according to the contamination levels. A combination of chemometric and molecular indices was used to identify the sources of PAHs, which could be attributed to vehicle emissions, oil combustion and biomass combustion. Source apportionment using absolute principle component scores–multiple linear regression showed that the main sources of PAHs are vehicle emissions 54%, oil 37% and biomass combustion 9%. Land-based pollution from vehicle emissions is the predominant contributor of PAHs in the aquaculture sediments of Peninsular Malaysia.
Afficher plus [+] Moins [-]A ten–year source apportionment study of ambient fine particulate matter in San Jose, California Texte intégral
2013
Wang, Yungang | Hopke, Philip K.
Fine particulate matter (PM2.5) composition data from the Speciation Trends Network (STN) site in San Jose, CA, were analyzed by positive matrix factorization (PMF) using U.S. Environmental Protection Agency (EPA) PMF version 5.0. These data were 24–h average mass concentrations and compositions obtained from samples taken every third day from October 2002 to February 2012. The eight identified sources include secondary sulfate, secondary nitrate, fresh sea salt, aged sea salt, diesel emission, road salt, gasoline vehicles, and wood combustion. The contributions to PM2.5 of these eight sources were 13.1%, 20.0%, 5.5%, 7.8%, 9.4%, 5.1%, 14.8, and 24.3%, respectively. The Ni–related industrial source, which was detected in previous PMF analysis, was not identified in our study and a sharp decrease in Ni concentrations was observed after the end of 2004. The contribution of road dust source decreased significantly after 2004 (Mann–Whitney test, p<0.01), which is probably the result of the city wide enhanced street sweeping programs starting in 2005. A 40% reduction in the wood combustion PM2.5 contribution between winter 2008 and winter 2009 was found. This decrease could be attributed to the San Francisco Bay Area Air Quality Management District (BAAQMD) wood burning rule implemented in July 2008. In the future, the effectiveness and benefits of the wood burning rule could be evaluated using the multi–wavelength aethalometer delta–c method.
Afficher plus [+] Moins [-]Photosynthetically active radiation loss in the atmosphere in North China Texte intégral
2013
Bai, Jianhui
Based on an understanding of energy, empirical formulas of hourly PAR (photosynthetically active radiation) under all sky conditions in North China were introduced and applied. An interesting and important phenomenon of the absorption of “water vapor factor” in 400–700 nm was studied and its real mechanism can be explained by the energy consumption of the substances (gas, liquid, solid–phase) through OH radicals during chemical and photochemical reactions. The PAR at the top of the atmosphere was estimated with good agreement. PAR losses in the atmosphere associated with “photochemical factor” and other materials in North China are spatial and seasonal dependence; their “annual” averages were 15.33 and 309.30 W m–2 in North China, respectively. The energy loss related to the “photochemical factor” should be considered in all kinds of basic processes in the atmosphere and model studies, including radiation transmission, photochemistry, air motion, and climate.
Afficher plus [+] Moins [-]Carbonaceous aerosols in a wood burning community in rural New Zealand Texte intégral
2013
Ancelet, Travis | Davy, P. K. (Perry K.) | Trompetter, William J. | Markwitz, A. (Andreas) | Weatherburn, David C.
Particulate matter (PM) in Masterton, New Zealand, a rural community with a population of 20 000, was studied during the winter to gain an understanding of the carbonaceous species and their influence on PM concentrations. The average PM10 concentration during the winter was 21.0±14.8 µg m–3, of which 64% was PM2.5. PM2.5 concentrations were found to be the main cause of elevated PM10 concentrations, and were responsible for exceedances of the New Zealand National Environmental Standard for PM10. Carbonaceous species were 47 and 77% of the total PM10 and PM2.5, respectively. Organic carbon (OC) concentrations were always higher than elemental carbon (EC) concentrations. OC and EC concentrations showed excellent correlation with PM2.5 concentrations, suggesting that combustion processes were the dominant source of PM. Stable isotope analysis yielded δ13C values ranging from –24.9 to –27.6‰, which is indicative of wood combustion. Analysis of particle–phase PAHs by thermal desorption GC/MS yielded an average total PAH concentration of 38.9±25.9ng m–3, accounting for 0.3% of the PM2.5. Analysis of all of the results revealed that residential wood burning for domestic heating was the main source of PM pollution in Masterton. The results of this study suggest that a PM10 standard alone, particularly in areas where wood combustion is common, may not be providing an adequate level of protection for the exposed population.
Afficher plus [+] Moins [-]Correlation between atmospheric deposition of Cd, Hg and Pb and their concentrations in mosses specified for ecological land classes covering Europe Texte intégral
2013
Schröder, Winfried | Pesch, Roland | Hertel, Anne | Schonrock, Simon | Harmens, Harry | Mills, Gina | Ilyin, Ilia
Referring to Europe as a whole and to single European countries, previous studies have shown that heavy metal concentrations in mosses (1) are primarily determined by atmospheric deposition of heavy metals; (2) are country and element–specific; and (3) agree well with respect to element–specific spatial patterns and temporal trends of atmospheric deposition of heavy metals. This paper investigates correlations between the concentrations of cadmium, lead and mercury in atmospheric deposition and mosses within the units of an ecological land classification of Europe. To this end, measurements from the 2005/2006 European moss survey and modeled atmospheric deposition in the previous three years were intersected with a map on ecologically defined land classes of Europe. Then, the minimum numbers of sampling sites required within the ecological land classes were computed. Considering spatial auto–correlations, subsequently the correlations between the concentrations of heavy metals in mosses and corresponding deposition were calculated and mapped for each of those ecological land classes containing moss sampling sites. It was concluded that the numbers of sampling sites within Europe and most participating countries as well as within most of the ecological land classes are sufficient for estimating the mean of measurements for the above mentioned three spatial levels within 20% of its true value with 95% confidence. Spatial patterns of correlations between the atmospheric deposition and bioaccumulation were shown to vary by element and ecologically defined land classes.
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