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Assessment of concentration, bioaccumulation and sources of polycyclic aromatic hydrocarbons in zooplankton of Chabahar Bay 全文
2016
Ziyaadini, Morteza | Mehdinia, Ali | Khaleghi, Leila | Nassiri, Mahmoud
The amounts and sources of polycyclic aromatic hydrocarbons (PAHs) and their bioaccumulation factors (BAFs) in the zooplankton community of Chabahar Bay were investigated. The highest amounts of total PAHs (tPAHs) in the water and zooplankton samples were 62.2ngL−1 and 1478.6ngg−1 dry weights, in near the Shahid Beheshti Port and desalination, respectively. The greatest amount of BAF (51,780) was obtained in the entry of Bay, and it was related to the phenanthrene accumulation. Using molecular ratio, the results showed that the major input source of PAH compounds in zooplankton of Chabahar Bay was pyrolytic (fuel) source.
显示更多 [+] 显示较少 [-]Impact of terrestrial mining and intensive agriculture in pollution of estuarine surface sediments: Spatial distribution of trace metals in the Gulf of Urabá, Colombia 全文
2016
Vallejo Toro, Pedro Pablo | Vásquez Bedoya, Luis Fernando | Correa, Iván Darío | Bernal Franco, Gladys Rocío | Alcántara-Carrió, Javier | Palacio Baena, Jaime Alberto
The Gulf of Urabá (northwestern Colombia) is a geostrategic region, rich in biodiversity and natural resources. Its economy is mainly based on agribusinesses and mining activities. In this research is determined the impact of these activities in bottom surface sediments of the estuary. Thus, grain size, total organic carbon, total nitrogen, carbonates, Ag, Al, Ca, Cr, Cu, Fe, Hg, Mg, Mn, Ni, Pb and Zn concentrations from 17 surface sediment samples were obtained and enrichment factors (EF) as well as geo-accumulation indices (Igeo) were calculated to determine the contamination level in the gulf. EF and Igeo values revealed that the estuary is extremely contaminated with Ag and moderately contaminated with Zn. Therefore, the observed enrichment of Ag may be explained as a residue of the extraction of gold and platinum-group metals and the enrichment with Zn associated mainly to pesticides used in banana plantations.
显示更多 [+] 显示较少 [-]Effect analysis on regeneration speed of continuous regeneration-diesel particulate filter based on NO2-assisted regeneration 全文
2016
E, Jiaqiang | Xie, Longfu | Zuo, Qingsong | Zhang, Guiju
In order to improve the regeneration speed of Continuous Regeneration-Diesel Particulate Filter (CR-DPF) based on NO2-assisted regeneration, a mathematic model of the NO2-assisted regeneration is developed and verified by experiments and numerical simulation. Furthermore, the influences on regeneration speed from exhaust airflow and filter structure are studied in NO2-assisted regeneration process of CR-DPF. The results show that: the regeneration speed will be increased due to the increase of the volume of the exhaust gas, the temperature of the exhaust gas, the concentration of the NO2 and the concentration of the O2 in exhaust gas, but the regeneration speed will be decreased under other conditions such as m(NO2)/m(PM) being less than its threshold in exhaust gas, the increase of the filter length in CR-DPF or the increase of the channel density when initial amount of the carbon particles in filter being less than its threshold, moreover, thickness of channel wall has no effect on regeneration speed. And the suitable range of values for some key parameters being useful for enhancing regeneration speed and reducing pressure drop of CR-DPF has been provided.
显示更多 [+] 显示较少 [-]Assessment of polycyclic aromatic hydrocarbons (PAHs) in mussels (Mytilus galloprovincialis) of Prince Islands, Marmara Sea 全文
2016
Balcıoğlu, Esra Billur
In this study, PAH analyses have been conducted on indigenous mussels. Mussel samples (Mytilus galloprovincialis) have been collected from seven stations of Prince Islands during September 2015. Concentrations of total determined PAHs (sum of 16 compounds) ranged between 664 and 9083ngg−1. The origin of PAHs has been found to be pyrolytic according to the PHE/ANT and FA/PYR ratios in Büyükada. For other islands, PAH origins have been observed as pyrolytic and petrogenic together according to the PHE/ANT, FA/PYR and BaA/CHR ratios.
显示更多 [+] 显示较少 [-]A baseline study of the metallothioneins induction and its reversibility in Neohelice granulata from the Bahía Blanca Estuary (Argentina) 全文
2016
Buzzi, N.S. | Marcovecchio, J.E.
A baseline study of the metallothioneins induction and its reversibility in Neohelice granulata from the Bahía Blanca Estuary (Argentina) 全文
2016
Buzzi, N.S. | Marcovecchio, J.E.
Contamination by heavy metals causes serious effects in marine systems. Nowadays, the combination of chemical and biological data is recommended in monitoring programs. Metallothioneins (MT) are early-warning signals of metal exposure and are widely used in biomonitoring. The present research evaluates the heavy metals levels in sediments and the MT synthesis in the crab Neohelice granulata from the Bahía Blanca Estuary (BBE). Then, the recovery capabilities of N. granulata followed by a depuration phase are assessed. Results demonstrate a slow decline in the level of metals in the study area. In relation to MT, female crabs showed elevated MT when compared to males. Furthermore, MT synthesis diminished after the depuration phase. These data constitute the first MT information in organisms from the BBE and may be considered as baseline for future studies in this matter. Although pollution level found was low, further biomonitoring considering both types of data is recommended.
显示更多 [+] 显示较少 [-]A baseline study of the metallothioneins induction and its reversibility in Neohelice granulata from the Bahía Blanca Estuary (Argentina) 全文
2016
Buzzi, Natalia Sol | Marcovecchio, Jorge Eduardo
Contamination by heavy metals causes serious effects in marine systems. Nowadays, the combination of chemical and biological data is recommended in monitoring programs. Metallothioneins (MT) are early-warning signals of metal exposure and are widely used in biomonitoring. The present research evaluates the heavy metals levels in sediments and the MT synthesis in the crab Neohelice granulata from the Bahía Blanca Estuary (BBE). Then, the recovery capabilities of N. granulata followed by a depuration phase are assessed. Results demonstrate a slow decline in the level of metals in the study area. In relation to MT, female crabs showed elevated MT when compared to males. Furthermore, MT synthesis diminished after the depuration phase. These data constitute the first MT information in organisms from the BBE and may be considered as baseline for future studies in this matter. Although pollution level found was low, further biomonitoring considering both types of data is recommended. | Fil: Buzzi, Natalia Sol. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Química Biológica; Argentina | Fil: Marcovecchio, Jorge Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad FASTA "Santo Tomas de Aquino"; Argentina. Universidad Tecnologica Nacional; Argentina
显示更多 [+] 显示较少 [-]Addressing aquatic hazard classification for metals, metal compounds and alloys in marine systems 全文
2016
Huntsman-Mapila, P. | Skeaff, J.M. | Pawlak, M. | Beaudoin, R.
New International Maritime Organization regulations require shippers to classify all solid bulk cargo to indicate whether they are Harmful to the Marine Environment (HME). The objective of this work was to adapt the freshwater Transformation/Dissolution Protocol (T/DP) to marine water to provide a method to determine, when compared with marine Ecotoxicity Reference Values (ERVs), whether a metal-bearing substance is HME. The substances examined were: Cu2O powder; Ni metal powder; Co3O4 powder; and a Ni–Co–Fe alloy, as wire cuttings, which were the same substances examined in the freshwater T/D validation study and afforded comparisons of the reactivity, or measure of the rate and extent of metal release from the metal-bearing substances in freshwater versus marine conditions. The marine T/D method is suitable for conducting examinations of metal-bearing substances with a wide range of reactivities, from the relatively reactive Cu2O powder and the alloy to the Co3O4 powder, which was the least reactive.
显示更多 [+] 显示较少 [-]Diversity of bacteria in ships ballast water as revealed by next generation DNA sequencing 全文
2016
Brinkmeyer, Robin
The bacterial diversity in ballast water from five general cargo ships calling at the Port of Houston was determined with ion semiconductor DNA sequencing (Ion Torrent PGM) of PCR amplified 16S rRNA genes. Phylogenetic analysis revealed that the composition of bacteria in ballast water did not resemble that of typical marine habitats or even open ocean waters where BWEs occur. The predominant group of bacteria in ships conducting BWEs was the Roseobacter clade within the Alphaproteobacteria. In contrast, Gammaproteobacteria were predominant in the ship that did not conduct a BWE. All the ships contained human, fish, and terrestrial plant pathogens as well as bacteria indicative of fecal or activated sludge contamination. Most of the 60 pathogens had not been detected in ballast water previously. Among these were the human pathogens Corynebacterium diptheriae and several Legionella species and the fish pathogens Francisella piscicida and Piscirickettsia salmonis.
显示更多 [+] 显示较少 [-]Cadmium concentration in liver and muscle of silky shark (Carcharhinus falciformis) in the tip of Baja California south, México 全文
2016
Terrazas-López, Rafael | Arreola-Mendoza, Laura | Galván-Magaña, Felipe | Anguiano-Zamora, Marlene | Sujitha, S.B. | Jonathan, M.P.
Cadmium concentrations were determined in the tissues of muscle and liver of Carcharhinus falciformis (silky shark) sampled in Todos Santos, Baja California South, Mexico. This is one of the main shark species for human consumption in Mexico. Results indicate that accumulation of Cd varied in both sexes, based on its metabolism, sex, maturity and other biological characteristics. High Cd values were observed in the liver of adults of male (529.61μgg−1) and female (457.43μgg−1), whereas, in muscular tissues it was low (0.37μgg−1) than the prescribed permissible limits for seafood (0.5μgg−1). Substantial correlations were observed between body length and Cd values in adults except young male due to faster growth rate and its metabolism. The study indicated the impact of environmental conditions in the accumulation of Cd and its risk to the food web structure in the marine environment and health hazard for humans.
显示更多 [+] 显示较少 [-]Geochemistry of phosphorus in sediment cores from Sishili Bay, China 全文
2016
Zhang, Yong | Gao, Xuelu | Wang, Changyou | Chen, Chen-Tung Arthur | Zhou, Fengxia | Yang, Yuwei
This paper presents the distribution of total phosphorus (P), inorganic P (IP) and organic P in sediment cores from Sishili Bay, China. Their concentrations (μmolg−1) ranged from 15.04 to 21.59, 12.43 to 18.27 and 0.15 to 5.11, respectively, showing 87.6–96.9% of TP is IP. The distribution of the fractionation of IP , obtained by a sequential extraction technique, was 1.9–3.2% for soluble and loosely bound P (Ex-P), 8.5–13.1% for Al-bound from (Al-P), 7.4–9.5% for Fe-bound P (Fe-P), 5.0–12.4% for reductant-soluble P (Oc-P), 9.7–15.6% for CaCO3-bound P (ACa-P) and 45.9–54.6% for detritus P (Det-P). The P distribution and concentration was consistent with other Chinese coastal seas. No significant difference was found for the sedimentary P forms between scallop cultivation area and background area, indicating that shellfish aquaculture did not have significant effect on the depositional environment in the studied area, at least in case of P.
显示更多 [+] 显示较少 [-]Damage and recovery assessment of the Philippines' mangroves following Super Typhoon Haiyan 全文
2016
Long, Jordan | Giri, Chandra | Primavera, Jurgenne | Trivedi, Mandar
We quantified mangrove disturbance resulting from Super Typhoon Haiyan using a remote sensing approach. Mangrove areas were mapped prior to Haiyan using 30m Landsat imagery and a supervised decision-tree classification. A time sequence of 250m eMODIS data was used to monitor mangrove condition prior to, and following, Haiyan. Based on differences in eMODIS NDVI observations before and after the storm, we classified mangrove into three damage level categories: minimal, moderate, or severe. Mangrove damage in terms of extent and severity was greatest where Haiyan first made landfall on Eastern Samar and Western Samar provinces and lessened westward corresponding with decreasing storm intensity as Haiyan tracked from east to west across the Visayas region of the Philippines. However, within 18months following Haiyan, mangrove areas classified as severely, moderately, and minimally damaged decreased by 90%, 81%, and 57%, respectively, indicating mangroves resilience to powerful typhoons.
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