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Growth, nutrient status, and photosynthetic response to diesel-contaminated soil of a cordgrass, Spartina argentinensis Полный текст
2014
Redondo-Gómez, Susana | Petenello, María C. | Feldman, Susana R.
The present study was conduced to investigate the tolerance limits of Spartina argentinensis, which occurs in inland marshes of the Chaco-Pampean regions of Argentina, to diesel-contaminated soil. A glasshouse experiment was designed to investigate the effect of diesel fuel from 0% to 3% on growth and photosynthetic apparatus of S. densiflora by measuring gas exchange and photosynthetic pigments. We also performed chemical analysis of plant samples, and determined mycorrhizal index. Tiller and root biomasses declined with increasing diesel fuel concentration, as well as photosynthetic rate (A). Reductions in A could be accounted for by non-stomatal limitations. Mycorrhizal roots of S. argentinensis were reduced by the presence of diesel fuel, but did not affect its nutritional status; in fact, most element concentrations increased with diesel contamination. Despite the negative effect of diesel-contaminated soil, S. argentinensis continued growing, which could be useful management options for phytorremediation of diesel-contaminated soils.
Показать больше [+] Меньше [-]Influence of urban runoff, inappropriate waste disposal practices and World War II on the heavy metal status of sediments in the southern half of Saipan Lagoon, Saipan, CNMI Полный текст
2014
Denton, Gary R.W. | Emborski, Carmen A. | Habana, Nathan C. | Starmer, John A.
Heavy metals were examined in sediments from the southern half of Saipan Lagoon. These waters provided tactical access for US troops during WWII and were heavily shelled at the time. Mercury profiles in sediments were, to some extent, reflective of this event. Samples from the southern end of the lagoon, where an old post-war dumpsite once existed, were found to be substantially enriched with Pb, Cu and Zn. Further north, the lagoon was primarily impacted by urban runoff. Metal enrichment in sediments from this region was generally highest at storm drain outlets and attenuated seawards. Moderate enrichment was rarely exceeded for any element other than Hg beyond the 50m mark. Sediment quality guidelines used to flag potentially adverse ecological health effects revealed no PEL exceedances. TEL exceedances for Pb and Cu were identified in sediments near the former dumpsite. The public health implications of the data are briefly addressed.
Показать больше [+] Меньше [-]On the quantity and composition of floating plastic debris entering and leaving the Tamar Estuary, Southwest England Полный текст
2014
Sadri, Saeed S. | Thompson, Richard C.
The majority of plastic debris found in the marine environment has land based sources and rivers are considered an important medium for transfer of this debris. Here we report on the quantity and composition of floating plastic debris collected from surface waters of the Tamar Estuary. This represents the first study of riverine transport of floating plastic debris into European waters during different tidal regimes. Plastics were found in a variety of forms and sizes and microplastics (<5mm) comprised 82% of the debris. The most abundant types of plastic were Polyethylene (40%), Polystyrene (25%) and Polypropylene (19%). There was a significant difference in size frequency distribution between the spring and neap tides with more fragments of larger size observed during spring tides. While it is clear that debris has accumulated on shorelines within the estuary, during our study this river did not identify as a net source or sink.
Показать больше [+] Меньше [-]Estimation of lost tourism revenue in Geoje Island from the 2011 marine debris pollution event in South Korea Полный текст
2014
Jang, Yong Chang | Hong, Sunwook | Lee, Jongmyoung | Lee, Mi Jeong | Shim, Won Joon
Following a period of heavy rainfall in July 2011, a large amount of marine debris was washed up on the beaches of Geoje Island, South Korea, affecting the island’s tourism industry. The tourism revenue decreased due to this pollution event and was estimated by multiplying the decreased number of visitors by the average expenditure of visitors to the beaches. Due to the fact that the visitor count at the Island’s beaches decreased from 890,435 in 2010 to 330,207 in 2011 (i.e., a reduction of 560,228 persons, 63%), the tourism revenue loss of the island was estimated to be US$29 – 37 million. This study is one of the few to consider the economic effects of marine debris.
Показать больше [+] Меньше [-]Long-term effects of elevated CO2 and temperature on the Arctic calanoid copepods Calanus glacialis and C. hyperboreus Полный текст
2014
Hildebrandt, Nicole | Niehoff, Barbara | Sartoris, Franz Josef
Long-term effects of elevated CO2 and temperature on the Arctic calanoid copepods Calanus glacialis and C. hyperboreus Полный текст
2014
Hildebrandt, Nicole | Niehoff, Barbara | Sartoris, Franz Josef
The sensitivity of copepods to ocean acidification (OA) and warming may increase with time, however, studies >10days and on synergistic effects are rare. We therefore incubated late copepodites and females of two dominant Arctic species, Calanus glacialis and Calanushyperboreus, at 0°C at 390 and 3000μatm pCO2 for several months in fall/winter 2010. Respiration rates, body mass and mortality in both species and life stages did not change with pCO2. To detect synergistic effects, in 2011 C. hyperboreus females were kept at different pCO2 and temperatures (0, 5, 10°C). Incubation at 10°C induced sublethal stress, which might have overruled effects of pCO2. At 5°C and 3000μatm, body carbon was significantly lowest indicating a synergistic effect. The copepods, thus, can tolerate pCO2 predicted for a future ocean, but in combination with increasing temperatures they could be sensitive to OA.
Показать больше [+] Меньше [-]Performance of the Arctic calanoid copepods Calanus glacialis and C. hyperboreus under elevated pCO2 and temperatures Полный текст
2014
Hildebrandt, Nicole | Niehoff, Barbara | Sartoris, Franz-Josef
The sensitivity of copepods to ocean acidification (OA) and warming may increase with time, however, studies >10 days and on synergistic effects are rare. We therefore incubated late copepodites and females of two dominant Arctic species, Calanus glacialis and Calanus hyperboreus, at 0 °C at 390 and 3000 µatm pCO2 for several months in fall/winter 2010. Respiration rates, body mass and mortality in both species and life stages did not change with pCO2. To detect synergistic effects, in 2011 C. hyperboreus females were kept at different pCO2 and temperatures (0, 5, 10 °C). Incubation at 10 °C induced sublethal stress, which might have overruled effects of pCO2. At 5 °C and 3000 µatm, body carbon was significantly lowest indicating a synergistic effect. The copepods, thus, can tolerate pCO2 predicted for a future ocean, but in combination with increasing temperatures they could be sensitive to OA.
Показать больше [+] Меньше [-]Long-term effects of elevated CO2 and temperature on the Arctic calanoid copepods Calanus glacialis and C. hyperboreus Полный текст
2014
Hildebrandt, Nicole | Niehoff, Barbara | Sartoris, Franz Josef
The sensitivity of copepods to ocean acidification (OA) and warming may increase with time, however, studies >10 days and on synergistic effects are rare. We therefore incubated late copepodites and females of two dominant Arctic species, Calanus glacialis and C. hyperboreus, at 0 °C at 390 and 3000 µatm pCO2 for several months in fall/winter 2010. Respiration rates, body mass and mortality in both species and life stages did not change with pCO2. To detect synergistic effects, in 2011 C. hyperboreus females were kept at different pCO2 and temperatures (0, 5, 10 °C). Incubation at 10 °C induced sublethal stress, which might have overruled effects of pCO2. At 5 °C and 3000 µatm, body carbon was significantly lowest indicating a synergistic effect. The copepods, thus, can tolerate pCO2 predicted for a future ocean, but in combination with increasing temperatures they could be sensitive to OA.
Показать больше [+] Меньше [-]Flume tank studies to elucidate the fate and behavior of diluted bitumen spilled at sea Полный текст
2014
King, Thomas L. | Robinson, Brian | Boufadel, Michel | Lee, Kenneth
An economical alternative to conventional crudes, Canadian bitumen, harvested as a semi-liquid, is diluted with condensate to make it viable to transport by pipeline to coastal areas where it would be shipped by tankers to global markets. Not much is known about the fate of diluted bitumen (dilbit) when spilled at sea. For this purpose, we conducted dilbit (Access Western Blend; AWB and Cold Lake Blend; CLB) weathering studies for 13days in a flume tank containing seawater. After six days of weathering, droplets detached from the AWB slick and were dense enough to sink in seawater. The density of CLB also increased, but at a slower rate compared to AWB, which was attributed to the high concentration of alkylated polycyclic aromatic hydrocarbons in it, which are more resistant to weathering. An empirical, Monod-type model was introduced and was found to closely simulate the increase in oil density with time. Such a model could be used within oil spill models.
Показать больше [+] Меньше [-]Spatio-temporal comparisons of imposex status and tissue organotin concentration in the whelk Reishia clavigera collected along the coasts of Dapeng Bay and Daya Bay, Shenzhen, China Полный текст
2014
Ho, Kevin K.Y. | Leung, Kenneth M.Y.
Organotin compounds (OTs) have caused widespread adverse effects on marine organisms. As no local restrictions on OT-based antifouling paints have been implemented in China, high concentrations of OTs still occur in coastal environments. In this study, we measured the imposex status and tissue concentrations of OTs in the whelk Reishia clavigera collected along the coast of Dapeng Bay and Daya Bay of Shenzhen, China in 2013. Our results showed that all female whelks suffered from the onset of imposex. The highest concentration of total OTs was 27,756μgkg−1 dry weight in the samples collected from Shuitousha. Triphenyltin was the most predominant residue, accounting for more than 97.8% of total OTs across all sites. Compared with the results from previous studies, the marine environment of this region is still heavily contaminated with OTs. Therefore, a tightened control is necessary to regulate the use and release of OTs in China.
Показать больше [+] Меньше [-]Perylene as an indicator of land-based plant biomarkers in the southwest Caspian Sea Полный текст
2014
Varnosfaderany, Mohammad Nemati | Bakhtiari, Alireza Riyahi | Gu, Zhaoyan | Chu, Guoqiang
In this study, 84 surface sediment samples, from 28 Iranian rivers, 45 surface sediment samples and 31 samples from one core in the southwest of the Caspian Sea were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs). The results showed high variability of perylene in coastal surface sediments (1.3–123.6ngg−1dw) and river sediments (0.5–111.1ngg−1dw). Core samples revealed high levels of perylene which increased with depth. Three diagnostic ratios (DRs) for source identification of perylene (Per/TPAH, Per/PAI and Py/Per) revealed a dominance of biogenic inputs to the surface layers (coasts and rivers) and diagenetic production of perylene in the sediment core. Hyrcanian forests with humid climates favor wood-degrading fungi and the production of perylene and its precursors. Biogenic production of perylene as a land plant derived biomarker can be used for the reconstruction of paleoclimatic conditions of the southwest Caspian Sea.
Показать больше [+] Меньше [-]Characterization of polycyclic aromatic hydrocarbon levels in the vicinity of a petrochemical complex located in a densely populated area of the Rio de Janeiro, Brazil Полный текст
2014
Oliveira, Rafael Lopes | Varandas, Luciana | Arbilla, Graciela
The Petrochemical Complex of Duque de Caxias, Rio de Janeiro, is situated on a coastal strip between Guanabara Bay and a mountainous region covered with tropical forest. The complex comprises a refinery, a thermal power plant and several petrochemical industries. Higher rates of particulate–matter emissions are found in the region, mainly due to diesel emissions and the industrial activities of this area. In 2009 and 2010, samples were collected in three sites, and the 16 polycyclic aromatic hydrocarbons (PAHs) that are designated as priority pollutants by the US Environmental Protection Agency were determined. The sites are located in the vicinity of the Petrochemical Complex, one of them is on a roadside and the others are urban areas around the industrial complex. Multivariate analyses and diagnostic ratios show that the three studied areas were different, and the emissions seemed to be due to both gasoline and diesel vehicles. The carcinogenic PAHs represented the main fraction of the total PAHs determined in the particulate matter, and because the region is densely populated, these values may represent a health concern. The results indicate that regarding PAHs, the principal impact of the petrochemical complex is the high increase in the traffic of diesel vehicles and related tailpipe emissions.
Показать больше [+] Меньше [-]Factors contributing to elevated concentrations of PM2.5 during wintertime near Boise, Idaho Полный текст
2014
Mwaniki, George Ruchathi | Rosenkrance, Chelsea | Will Wallace, H. | Tom Jobson, B. | Erickson, Mathew H. | Lamb, Brian K. | Hardy, Rick J. | Zalakeviciute, Rasa | VanReken, Timothy M.
Wintertime chemical composition of water–soluble particulate matter with aerodynamic diameter less than 2.5μm (PM2.5) was monitored in the Treasure Valley region near Boise, Idaho. Aerosol was sampled using a Particle Into Liquid Sampler (PILS) and subsequently analyzed using ion exchange chromatography and a total organic carbon analyzer. During the two–month sampling campaign, the region experienced varying meteorological regimes, with an extended atmospheric stagnation event towards the end of the study. For all of the weather regimes, water–soluble PM2.5 was dominated by organic material, but particulate nitrate showed the greatest variation over time. These variations in particulate nitrate concentration were found to be dependent on the time of day, nitrogen oxides (NOX) concentrations, and relative humidity. The increases in particulate nitrate did not correlate with an equivalent molar increase of ammonium concentration, ruling out solid ammonium nitrate formation as the dominant source. Instead, our analysis using an online aerosol thermodynamic model suggests that the condensation of gas phase nitric acid was possible within the meteorological conditions experienced during the study. In running this model, atmospheric chemical and physical parameters close to those observed during the study were used as model input. The simulation was run for three different scenarios, representing the different meteorological regimes experienced during the study. From the simulation particulate nitrate concentration was highest during cold and humid nights. Currently this region is in attainment with the National Ambient Air Quality Standards (NAAQS) for PM2.5; however, with the projected increase in population and economic growth, and the subsequent increase in NOX emissions, these episodic increases in particulate nitrate have the potential of pushing the area to non–attainment status.
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