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Ingestion of marine litter by loggerhead sea turtles, Caretta caretta, in Portuguese continental waters
2016
Nicolau, Lídia | Marçalo, Ana | Ferreira, Marisa | Sá, Sara | Vingada, José | Eira, Catarina
The accumulation of litter in marine and coastal environments is a major threat to marine life. Data on marine litter in the gastrointestinal tract of stranded loggerhead turtles, Caretta caretta, found along the Portuguese continental coast was presented. Out of the 95 analysed loggerheads, litter was present in 56 individuals (59.0%) and most had less than 10 litter items (76.8%) and less than 5g (dm) (96.8%). Plastic was the main litter category (frequency of occurrence=56.8%), while sheet (45.3%) was the most relevant plastic sub-category. There was no influence of loggerhead stranding season, cause of stranding or size on the amount of litter ingested (mean number and dry mass of litter items per turtle). The high ingested litter occurrence frequency in this study supports the use of the loggerhead turtle as a suitable tool to monitor marine litter trends, as required by the European Marine Strategy Framework Directive.
Показать больше [+] Меньше [-]Atmospheric consequences of trade and human development: A case of BRIC countries
2016
Sinha, Avik | Sen, Sudipta
This paper looks into the causal association between economic growth, CO2 emission, trade volume, and human development indicator for Brazil, Russia, India, and China (BRIC countries) during 1980–2013. Following a generalized method of moments (GMM) technique, we have found out that bidirectional causality exists between CO2 emissions and economic growth. Feedback hypothesis is supported between CO2 emissions and human development, trade volume and human development, economic growth, and human development, and CO2 emissions and trade volume. Apart from finding out the unidirectional association from trade volume to economic growth, this study also validated the existence of Environmental Kuznets curve. Empirical findings of the study substantiate that the policymakers of the BRIC nations must focus on the green energy initiatives, either by in-house development or by technology transfer. This movement will allow them to control the ambient air pollution prevalent in these nations.
Показать больше [+] Меньше [-]Nutrient distribution and structure affect the acidification of eutrophic ocean margins: A case study in southwestern coast of the Laizhou Bay, China
2016
Zhang, Jinfeng | Gao, Xuelu
The effects of nutrient distribution and structure on the acidity of coastal waters were analyzed based on the data of 48 surface water samples collected in the southwestern coast of the Laizhou Bay and its adjacent rivers (SWLZB) which are heavily influenced by nutrient-laden discharges. The concentration and structure of nutrients varied considerably along the coast owing to different contributors. The studied inshore waters exhibited a sign of acidification. The pH was significantly negatively correlated with the concentration of NO3-N, NO2-N, NH4-N and DSi, but showed no obvious correlation with the concentration of PO4-P and the ratio of TDN/TDP, DSi/DIN and DSi/PO4-P, respectively. The results indicated that the distribution of nutrients might well be an important environmental factor affecting the acidification of the SWLZB in warmer months.
Показать больше [+] Меньше [-]Application of novel image base estimation of invisible leaf injuries in relation to morphological and photosynthetic changes of Phaseolus vulgaris L. exposed to tropospheric ozone
2016
Drapikowska, M. | Drapikowski, P. | Borowiak, K. | Hayes, F. | Harmens, H. | Dziewiątka, T. | Byczkowska, K.
This study aimed to evaluate the degree of Phaseolus vulgaris L. (bean) leaf tissue injury caused by tropospheric ozone. To validate O3 symptoms at the microscopic level, Evans blue staining together with an image processing method for the removal of distortions and calculation of dead leaf areas was applied. Net photosynthetic rate (PN), stomatal conductance (gs) and intercellular CO2 concentration (Ci) were determined to evaluate leaf physiological responses to ozone. It was found that both resistant and sensitive varieties of bean were damaged by ozone; however, the size of necrotic and partially destroyed leaf area in the sensitive genotype (S156) was bigger (1.18%, 2.18%) than in the resistant genotype (R123), i.e. 0.02% and 0.50%. Values of net photosynthetic rates were lower in the sensitive genotype in ambient air conditions, than in the resistant genotype in ambient air conditions. We further found that there was a correlation between physiological and anatomical injuries; net photosynthetic rate (PN) was negatively correlated with percentage of necrotic area of both genotypes, while stomatal conductance (gs), intercellular CO2 concentration (Ci) were positively correlated with percentage of necrotic tissue of both genotypes. Moreover, visible injures in both genotypes were positively correlated with percentage of anatomical injures. In conclusion, the presented combinations of morphological, anatomical and physiological markers allowed differential diagnosis of ozone injury.
Показать больше [+] Меньше [-]Preliminary investigation of perfluoroalkyl substances in exploited fishes of two contaminated estuaries
2016
Taylor, Matthew D. | Johnson, Daniel D.
Perfluoroalkyl substances (PFASs) are being increasingly detected in a range of aquatic and terrestrial ecosystems, often resulting from the use of legacy fire-fighting foams. This study conducted an initial investigation of the concentrations of PFASs in the commercially and recreationally exploited species Dusky Flathead, Mud Crab, School Prawn, Sea Mullet, Yellowfin Bream, Eastern King Prawn and Sand Whiting, across two contaminated estuaries. All samples contained perfluoro-n-octane sulfonate (PFOS) except four Yellowfin Bream samples (two from each estuary). Perfluoro-n-octanoic acid (PFOA) was detected only in School Prawn samples from Fullerton Cove, while perfluoro-n-hexane sulfonate (PFHxS) was detected in prawn muscle and in fish liver samples from both estuaries. This study presents one of the first surveys of PFAS in a range of edible saltwater fish and crustaceans in Australia, and these baseline levels of contamination will prove useful for informing future surveys of these emerging contaminants.
Показать больше [+] Меньше [-]Effects of sedimentary sulfide on community structure, population dynamics, and colonization depth of macrozoobenthos in organic-rich estuarine sediments
2016
Kanaya, Gen | Uehara, Tadayasu | Kikuchi, Eisuke
An annual field survey and in situ recolonization experiment revealed the effects of sedimentary sulfide (H2S) on macrozoobenthos in a eutrophic brackish lagoon. Species diversity was much lower throughout the year in muddy opportunist-dominant sulfidic areas. Mass mortality occurred during warmer months under elevated H2S levels. An enclosure experiment demonstrated that sedimentary H2S modified community composition, size structure, and colonization depth of macrozoobenthos. Species-specific responses to each sediment type (sand, sulfidic mud, and mud with H2S removed) resulted in changes in the established community structure. Dominant polychaetes (Hediste spp., Pseudopolydora spp., and Capitella teleta) occurred predominantly in a thin surface layer in the presence of H2S. On the other hand, organic-rich mud facilitated settlement of polychaete larvae if it does not contain H2S. These results demonstrate that sediment characteristics, including H2S level and organic content, were key structuring factors for the macrozoobenthic assemblage in organically polluted estuarine sediments.
Показать больше [+] Меньше [-]Chemical Processes Affecting the Mobility of Heavy Metals and Metalloids in Soil Environments
2016
Caporale, Antonio G. | Violante, Antonio
The mobility, bioavailability, and toxicity of metal(loid)s are influenced by their interactions with phyllosilicates, organic matter, variable charge minerals, and microorganisms. Physicochemical processes influencing the chemistry of metal(loid)s in soil environments include sorption/desorption, solution complexation, oxidation-reduction, and precipitation-dissolution reactions. In particular, the sorption/desorption reactions of metal(loid)s on/from soil sorbents are influenced by pH, nature of soil components, and presence and concentrations of cations and inorganic anions. In recent years, many extraction tests have been used for assessing trace elements mobility and phytoavailability. Chemical speciation of toxic elements may be achieved by spectroscopic analyses (XAS), which provide information about oxidation state, symmetry, and identity of the coordinating ligand environment, and possible solid phases.
Показать больше [+] Меньше [-]Managing Groundwater Nitrate Contamination from Livestock Farms: Implication for Nitrate Management Guidelines
2016
Sahoo, Prafulla Kumar | Kim, Kangjoo | Powell, M. A.
Significant nitrate contamination of groundwater has been observed in various parts of the world; intensive livestock farming is one of the major causes. This paper reviews various guidelines/regulations, which have been developed in advanced countries such as USA, Canada, Australia, and Europe to combat this problem by designing effective monitoring and management programs. Monitoring programs deal mainly with selection of sites, number of monitoring wells, specific parameters, and sampling frequency, which are helpful for identifying the source and extend of the contamination. Management programs deal with selection of suitable location, site characterization, proximity of livestock facilities and drinking wells, and proper storage, maintenance of the facilities, and limits of manures application in order to minimize nitrate leaching into groundwater. The main aim of this paper is to help states/countries, which do not have any guideline, and consulting engineers/consultants/owners of livestock operation in the design of effective strategies for point source nitrate management.
Показать больше [+] Меньше [-]A novel bioassay using the barnacle Amphibalanus amphitrite to evaluate chronic effects of aluminium, gallium and molybdenum in tropical marine receiving environments
2016
van Dam, Joost W. | Trenfield, Melanie A. | Harries, Simon J. | Streten, Claire | Harford, Andrew J. | Parry, David | van Dam, Rick A.
A need exists for appropriate tools to evaluate risk and monitor potential effects of contaminants in tropical marine environments, as currently impact assessments are conducted by non-representative approaches. Here, a novel bioassay is presented that allows for the estimation of the chronic toxicity of contaminants in receiving tropical marine environments. The bioassay is conducted using planktonic larvae of the barnacle Amphibalanus amphitrite and is targeted at generating environmentally relevant, chronic toxicity data for water quality guideline derivation or compliance testing. The developmental endpoint demonstrated a consistently high control performance, validated through the use of copper as a reference toxicant. In addition, the biological effects of aluminium, gallium and molybdenum were assessed. The endpoint expressed high sensitivity to copper and moderate sensitivity to aluminium, whereas gallium and molybdenum exhibited no discernible effects, even at high concentrations, providing valuable information on the toxicity of these elements in tropical marine waters.
Показать больше [+] Меньше [-]Sensitivity of online coupled model to extreme pollution event over a mega city Delhi
2016
Srinivas, Reka | Panicker, Abhilash S. | Parkhi, Neha S. | Peshin, Sunil K. | Beig, Gufran
Sensitivity of interactive Weather-Chemistry model has been examined to predict the air quality (1 and 3 days in advance) of Indian mega city Delhi during two identical extreme events of Diwali in 2012 and 2013. Analysis is conducted 3 days prior to 3 days later of Diwali day for both events to verify the rapid changes in fine particulate matter (PM2.5) due to widespread display of Diwali fireworks. The model successfully predicted the variability in PM2.5 during 2012 for the entire period of analysis with reasonable accuracy. Although model performed reasonably well until Diwali day in 2013 but it was unable to simulate rapid built up of PM2.5 (1500 μg−3 hourly average) during post Diwali day as it failed to capture unusual mid-night steep temperature gradient followed by a record lowering of boundary layer height. The predictability of the model and its limitation to micrometeorological processes are discussed in detail.
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