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Cultivation of activated sludge using sea mud as seed to treat industrial phenolic wastewater with high salinity 全文
2017
Tan, Songwen | Cui, Chunzhi | Hou, Yang | Chen, Xuncai | Xu, Aiqin | Li, Weiguo | You, Hong
A technique is proposed to treat saline hazardous wastewater by using marine activated sludge, cultivated with sea mud as seed. Since the developed marine activated sludge had phenol-tolerant microorganisms (MAS-1, MAS-2 and MAS-3) which originated from the ocean, it was envisaged that these bacteria could survive and breakdown phenol in saline environments. In this work, typical phenol-tolerant microorganisms were isolated from the marine activated sludge and identified. After a hierarchical acclimation process, the marine activated sludge was used to treat the industrial phenolic wastewater with high salinity. The marine activated sludge was able to break down phenol and other organic components effectively and efficiently in treating the wastewater with salinity of 5.7% w/v. The results showed a high removal of phenol (99%), COD (80%) and NH3-N (68%).
显示更多 [+] 显示较少 [-]Microplastic abundance, distribution and composition along a latitudinal gradient in the Atlantic Ocean 全文
2017
Kanhai, La Daana K. | Officer, Rick | Lyashevska, Olga | Thompson, Richard C. | O'Connor, Ian
Microplastics in the world's oceans are a global concern due to the potential threat they pose to marine organisms. This study investigated microplastic abundance, distribution and composition in the Atlantic Ocean on a transect from the Bay of Biscay to Cape Town, South Africa. Microplastics were sampled from sub-surface waters using the underway system of the RV Polarstern. Potential microplastics were isolated from samples and FT-IR spectroscopy was used to identify polymer types. Of the particles analysed, 63% were rayon and 37% were synthetic polymers. The majority of microplastics were identified as polyesters (49%) and blends of polyamide or acrylic/polyester (43%). Overall, fibres (94%) were predominant. Average microplastic abundance in the Atlantic Ocean was 1.15±1.45particlesm−3. Of the 76 samples, 14 were from the Benguela upwelling and there was no statistically significant difference in microplastic abundance between upwelled and non-upwelled sites.
显示更多 [+] 显示较少 [-]Environmental drivers of heterogeneity in the trophic-functional structure of protozoan communities during an annual cycle in a coastal ecosystem 全文
2017
Xu, Guangjian | Yang, Eun Jin | Xu, Henglong
Trophic-functional groupings are an important biological trait to summarize community structure in functional space. The heterogeneity of the tropic-functional pattern of protozoan communities and its environmental drivers were studied in coastal waters of the Yellow Sea during a 1-year cycle. Samples were collected using the glass slide method at four stations within a water pollution gradient. A second-stage matrix-based analysis was used to summarize spatial variation in the annual pattern of the functional structure. A clustering analysis revealed significant variability in the trophic-functional pattern among the four stations during the 1-year cycle. The heterogeneity in the trophic-functional pattern of the communities was significantly related to changes in environmental variables, particularly ammonium-nitrogen and nitrates, alone or in combination with dissolved oxygen. These results suggest that the heterogeneity in annual patterns of protozoan trophic-functional structure may reflect water quality status in coastal ecosystems.
显示更多 [+] 显示较少 [-]Can we assess the ecological status of estuaries based on larval fish assemblages? 全文
2017
Santos, Régis Vinícius Souza | Ramos, Sandra | Bonecker, Ana Cristina Teixeira
Fish larvae of four SE Brazilian estuaries were investigated to assess if the larval fish assemblages reflect the ecological status of estuaries. All samples were collected in the same water mass to guarantee similar natural water parameters, assuring that major differences among estuaries were related to anthropogenic pressures. Water temperature, oxygen, pH, chlorophyll a, faecal coliforms, nutrient load and total particulate matter were obtained at each sampling area. A pressure index was used to assess the overall anthropogenic pressures acting in each estuary. Results showed that fish larvae were sensitive to water contamination, reducing the diversity and especially exhibiting a high dominance of few species. Furthermore, this study reinforced the idea that the high sensitivity of fish larvae can increase the accuracy of the environmental assessments when tackling short-time events of hydrological controls (physical barriers and control of the freshwater input), representing an advance in the water ecological quality assessments.
显示更多 [+] 显示较少 [-]Heavy metal concentrations in some gastropods and bivalves collected from the fishing zone of South India 全文
2017
Ragi, A.S. | Leena, P.P. | Cheriyan, Eldhose | Nair, S.M.
The present study investigates heavy metal concentrations in gastropods and bivalves collected from major fishing centers in South India. Three gastropods, Bursa spinosa, Tibia curta, and Murex trapa, and two bivalves, Perna viridis and Villoritta cyprinoids, were collected for the analysis of heavy metals. The metals in the present study followed the order Mg>Ca>Zn>Fe>Cu>Mn>Cr>Pb>Ni>Co>Cd. Trace metal concentrations in the soft tissue of the molluscs varied as follows: for Cd: 0.04–5.33, Co: 0.09–0.87, Cr: 2.18–7.59, Cu: 9.54–37.02, Mn: 1.30–8.50, Ni: 0.94–3.21, Pb: 1.16–2.64 and Zn: 68.16–113.64mgkg−1. Metal concentrations in all the species were below the limits proposed by the World Health Organization, except for Pb and Cd. This baseline study suggests that the levels of toxic metals in M. trapa, T. curta, and B. spinosa should be continuously monitored to assess the fate and effects of these metals in this fragile ecosystem.
显示更多 [+] 显示较少 [-]Determination and speciation of cadmium in microcosms with Bunodosoma caissarum and Perna perna using isotopically enriched 116Cd 全文
2017
Rizzini Ansari, Nafisa | Fernández Iglesias, Nerea | Cordeiro, Renato Campello | Fernandez, Marcos Antônio | Bettmer, Jörg
The study of the uptake and distribution of elements in marine environments is of great interest for understanding their pathways and accumulation. Here, we investigated in laboratory experiments the accumulation behavior of Cd in the sea anemone Bunodosoma caissarum and the mussel Perna perna. Specimens were incubated with isotopically enriched 116Cd in aquariums. Cd concentrations in the seawater and in the tissues of B. caissarum and P. perna were followed by inductively coupled plasma-mass spectrometry (ICP-MS) by means of isotope dilution analysis. Bioconcentration factors for B. caissarum and P. perna exposed to 0.9μg·L−1 of 116Cd were determined to be 80.5 and 850, respectively. P. perna specimens exposed to 4.5μg·L−1 of 116Cd reached 530. Cytosolic proteins associated with Cd from the tissues were extracted and further analyzed by size-exclusion chromatography coupled to ICP-MS. Cd accumulation could be detected in both organisms ranging from high-molecular to low-molecular species.
显示更多 [+] 显示较少 [-]Immunotoxic effects of single and combined pharmaceuticals exposure on a harbor seal (Phoca vitulina) B lymphoma cell line 全文
2017
Kleinert, Christine | Lacaze, Emilie | Mounier, Méryl | De Guise, Sylvain | Fournier, Michel
The potential risk of pharmaceuticals in the environment to top-predators is still largely unknown. In this study, we assessed the immunotoxic effects of ten pharmaceuticals individually and as mixtures on a harbor seal (Phoca vitulina) B lymphoma cell line. A significant reduction in lymphocyte transformation was observed following an exposure to 12,500μg/L 17α-ethinyl estradiol and 25,000μg/L naproxen. Exposure to 12,500μg/L 17α-ethinyl estradiol decreased the percentage of cell in the G0/G1 phase of the cell cycle while increasing the percentage of cells in the S phase. Carbamazepine exposure increased the amount of cells in the G2/M phase. Binary mixtures showed synergistic effects in lymphocyte transformation, cell cycle and apoptosis assays. Concentrations inducing toxic effects in the cell line were similar to those affecting fish in previous studies. A reduction of functional activities of the immune system may lead to altered host resistance to pathogens in free-ranging pinnipeds.
显示更多 [+] 显示较少 [-]Marine environment status assessment based on macrophytobenthic plants as bio-indicators of heavy metals pollution 全文
2017
Zalewska, Tamara | Danowska, Beata
The main aim of study was to develop the environmental quality standards (EQSMP) for selected heavy metals: Pb, Cd, Hg and Ni bioaccumulated in the tissues of marine macrophytobenthic plants: Chara baltica, Cladophora spp., Coccotylus truncatus, Furcellaria lumbricalis, Polysiphonia fucoides, Stuckenia pectinata and Zanichellia palustris, collected in designated areas of the southern Baltic Sea in period 2008–2015. The calculated concentration ratios (CR), which attained very high values: 104Lkg−1 for lead, 103Lkg−1 for nickel and mercury and even 105Lkg−1 for cadmium formed the basis for the determination of EQSMP values. The EQSMP values were: 26mgkg−1d.w. for Pb, 33mgkg−1d.w. for Cd, 32mgkg−1d.w. for Ni and 0.4mgkg−1d.w. for Hg. The application of macrophytobenthic plants as bioindicators in marine environment status assessment of certain areas of the Baltic Sea is also described in the paper.
显示更多 [+] 显示较少 [-]Daily relative dog abundance, fecal density, and loading rates on intensively and minimally managed dog-friendly beaches in central California 全文
2017
Oates, Stori C. | Miller, Melissa A. | Hardin, Dane | Dominik, Clare | Jessup, David | Smith, Woutrina A.
Due to increased concerns regarding fecal pollution at marine recreational beaches, daily relative dog abundance and fecal density were estimated on an intensively managed (Beach 1) and a minimally managed (Beach 2) dog beach in Monterey County, California. Fecal loading and factors predictive of fecal deposition also were assessed. After standardizing for beach area, daily beach use and fecal densities did not differ between beaches and yearly fecal loading estimates revealed that unrecovered dog feces likely contributes significantly to fecal contamination (1.4 and 0.2metrictonnes/beach). Detection of feces was significantly associated with beach management type, transect position relative to mean low tideline, presence of beach wrack, distance to the nearest beach entrance, and season. Methodologies outlined in this study can augment monitoring programs at coastal beaches to optimize management, assess visitor compliance, and improve coastal water quality.
显示更多 [+] 显示较少 [-]Assessing environmental health using ecological indices for soft bottom in sewage-affected rocky shores: The case of the largest seaside resort of SW Atlantic 全文
2017
Garaffo, GV | Jaubet, ML | Becherucci, ME | Elías, R
Efficient ecological indices can reflect the differences between impacted and nonimpacted sites, leading to significant variations at the contamination spatial scale. Here, we evaluated the spatial-temporal variability of 3 ecological indices (AMBI, M-AMBI, and BENTIX) in response to the distinct levels of sewage contamination. The indices were evaluated in two different ways: including Brachidontes rodriguezii (IBR) and excluding B. rodriguezii (EBR). The fact that mussel beds create a secondary infaunal habitat allows us to test these indices for soft bottoms in areas with rocky bottoms. The effectiveness and the level of agreement of these indices were increased when they were calculated with EBR. BENTIX and M-AMBI produced under- and overestimations of the ecological status of the studied sites. AMBI (EBR) seems to be better suited for environmental quality assessment in the study area. This index reduces the processing time of samples; thus, the AMBI (EBR) index could be used as a robust management tool for monitoring programs in areas with hard substrate.
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