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Water flux management and phytoplankton communities in a Mediterranean coastal lagoon. Part I: How to promote dinoflagellate dominance? Полный текст
2016
Garrido, M. | Cecchi, P. | Collos, Y. | Agostini, S. | Pasqualini, V.
The Biguglia lagoon is a shallow Mediterranean coastal ecosystem where eutrophication is increasing for years. A channel supplying freshwater was cleared in 2009 to enhance lagoon water circulation and alleviate dystrophic crises. Monthly monitoring was started in 2010 to document the impacts of this action on abiotic characteristics and phytoplankton communities. Three stations were surveyed (by microscopy and HPLC). Evidence suggests that this operation had an unexpected outcome. Salinity footprints indicated the succession of three main hydrological sequences that depended on rainfall and circulation pattern. Diatoms and dinoflagellates dominated the first sequence, characterized by heavy rainfall, while Prorocentrum minimum became progressively the dominant species in the second period (increasing salinities) with extensive bloom over the whole lagoon (5.93×10-5cells·L−1) during the third period. These phytoplankton successions and community structures underline the risk of pernicious effects arising from remediation efforts, in the present case based on increasing freshwater inputs.
Показать больше [+] Меньше [-]Paralytic shellfish toxin production by the dinoflagellate Alexandrium pacificum (Chinhae Bay, Korea) in axenic, nutrient-limited chemostat cultures and nutrient-enriched batch cultures Полный текст
2016
Han, Myungsoo | Lee, Haeok | Anderson, Donald M. | Kim, Baikho
Blooms of Alexandrium pacificum (formerly Alexandrium tamarense) are common in Chinhae Bay (Korea), presumably linked to anthropogenic eutrophication. Here we examine PSP toxin content and composition in axenic chemostat and batch cultures of A. pacificum using growth conditions that differed according to dilution rate, nutrient limitations, and enrichments. Phosphate (P)-limited cells in chemostat cultures had higher toxin content and a toxin composition that differed from that of nitrogen (N)-limited cells at the highest growth rates. Therefore, toxin composition changes do occur in axenic cultures of A. pacificum following extended growth under steady state conditions. In nutrient-limited batch cultures that received N and P enrichment, the N-enriched cultures showed a more diverse toxin profile than the P-enriched cells; the toxin content of N-enriched cells was lower than in the P-enriched cultures. We infer the following order for the biosynthesis of individual toxins: C1, C2>GTX3>GTX1>neoSTX.
Показать больше [+] Меньше [-]Assessment of metal enrichment and their bioavailability in sediment and bioaccumulation by mangrove plant pneumatophores in a tropical (Zuari) estuary, west coast of India Полный текст
2016
Noronha-D'Mello, Cheryl A. | Nayak, G.N.
Sediment collected from the estuarine mangroves of the Zuari estuary and Cumbharjua canal were analyzed to assess the concentration, contamination and bioavailability of metals. Mangrove pneumatophores were also analyzed to understand the metal bioaccumulation in mangrove plants. The results indicated the variation of metal concentrations in sediment along the estuary was attributed to changing hydrodynamic conditions, type of sediment and metal sources. Further, speciation studies revealed that Fe, Cr, Co, Ni, Cu and Zn were mainly of lithogenic origin and less bioavailable while high Mn content in the sediment raised concerns over its potential mobility, bioavailability and subsequent toxicity. The mangrove plants exhibited difference in metal accumulation due to variations in sediment parameters and metal availability, in addition to difference in plant species and tissue physiology that affect metal uptake. Moreover, the mangrove plants reflected the quality of the underlying sediment and can be used as a potential bio-indicator tool.
Показать больше [+] Меньше [-]Comparison of heavy metal contamination during the last decade along the coastal sediment of Pakistan: Multiple pollution indices approach Полный текст
2016
Saher, Noor Us | Siddiqui, Asmat Saleem
Heavy metals concentrations (Fe, Cu, Zn, Ni, Cr, Co, Pb, and Cd) were scrutinized during two monitoring years (2001 and 2011) in the coastal sediment of Pakistan. The status of metal contamination in coastal sediment was interpreted using sediment quality guidelines, and single and combined metal pollution indices. Ni, Cr, and Cd were recognized for their significant (p<0.05) intensification in the sediment during the last decade. Sediment quality guidelines recognized the frequent adverse biological effect of Ni and the occasional adverse biological effect of Cu, Cr, Pb and Cd. Single metal pollution indices (Igeo, EF, CF, and ER) revealed that sediment pollution is predominantly caused by Pb and Cd. Low to moderate contamination was appraised along the coast by multi-metal pollution indices (CD and PERI). Correlation study specifies that heavy metals were presented diverse affiliations and carriers for distribution in the sediment during the last decade.
Показать больше [+] Меньше [-]Spatial variability and response to anthropogenic pressures of assemblages dominated by a habitat forming seaweed sensitive to pollution (northern coast of Alboran Sea) Полный текст
2016
Bermejo, Ricardo | de la Fuente, Gina | Ramírez-Romero, Eduardo | Vergara, Juan J. | Hernández, Ignacio
Spatial variability and response to anthropogenic pressures of assemblages dominated by a habitat forming seaweed sensitive to pollution (northern coast of Alboran Sea) Полный текст
2016
Bermejo, Ricardo | de la Fuente, Gina | Ramírez-Romero, Eduardo | Vergara, Juan J. | Hernández, Ignacio
The Cystoseira ericaefolia group is conformed by three species: C. tamariscifolia, C. mediterranea and C. amentacea. These species are among the most important habitat forming species of the upper sublittoral rocky shores of the Mediterranean Sea and adjacent Atlantic coast. This species group is sensitive to human pressures and therefore is currently suffering important losses. This study aimed to assess the influence of anthropogenic pressures, oceanographic conditions and local spatial variability in assemblages dominated by C. ericaefolia in the Alboran Sea. The results showed the absence of significant effects of anthropogenic pressures or its interactions with environmental conditions in the Cystoseira assemblages. This fact was attributed to the high spatial variability, which is most probably masking the impact of anthropogenic pressures. The results also showed that most of the variability occurred on at local levels. A relevant spatial variability was observed at regional level, suggesting a key role of oceanographic features in these assemblages.
Показать больше [+] Меньше [-]Spatial variability and response to anthropogenic pressures of assemblages dominated by a habitat forming seaweed sensitive to pollution (northern coast of Alboran Sea) Полный текст
2016
Bermejo-Lacida, Ricardo | de la Fuente, Gina | Ramírez-Romero, Eduardo | Vergara, Juan J. | Hernández, Ignacio
El copyright de esta publicación pertenece al editor en exclusiva, no está permitido el acceso al texto completo. | The Cystoseira ericaefolia group is conformed by three species: C. tamariscifolia, C. mediterranea and C. amentacea. These species are among the most important habitat forming species of the upper sublittoral rocky shores of the Mediterranean Sea and adjacent Atlantic coast. This species group is sensitive to human pressures and therefore is currently suffering important losses. This study aimed to assess the influence of anthropogenic pressures, oceanographic conditions and local spatial variability in assemblages dominated by C. ericaefolia in the Alboran Sea. The results showed the absence of significant effects of anthropogenic pressures or its interactions with environmental conditions in the Cystoseira assemblages. This fact was attributed to the high spatial variability, which is most probably masking the impact of anthropogenic pressures. The results also showed that most of the variability occurred on at local levels. A relevant spatial variability was observed at regional level, suggesting a key role of oceanographic features in these assemblages. | Contract OT 2010/102 between the University of Cadiz and the Environmental Division of the Autonomic Government (Junta de Andalucía) Sapanish national project CTM2011-24482 (SEA-LIVE); R. Bermejo holds a FPU fellowship of the Spanish Ministry of Education. European Commission (OCEAN-CERTAIN, FP7-ENV- 2013-6.1-1; no: 603773).
Показать больше [+] Меньше [-]First comprehensive screening of lipophilic organic contaminants in surface waters of the megacity Jakarta, Indonesia Полный текст
2016
Dsikowitzky, L. | Sträter, M. | Dwiyitno, | Ariyani, F. | Irianto, H.E. | Schwarzbauer, J.
Jakarta is an Indonesian coastal megacity with over 10 million inhabitants. The rivers flowing through the city receive enormous amounts of untreated wastewaters and discharge their pollutant loads into Jakarta Bay. We utilized a screening approach to identify those site-specific compounds that represent the major contamination of the cities' water resources, and detected a total number of 71 organic contaminants in Jakarta river water samples. Especially contaminants originating from municipal wastewater discharges were detected in high concentrations, including flame retardants, personal care products and pharmaceutical drugs.A flame retardant, a synthetic fragrance and caffeine were used as marker compounds to trace the riverine transport of municipal wastewaters into Jakarta Bay. These markers are also appropriate to trace municipal wastewater discharges to other tropical coastal ecosystems. This application is in particular useful to evaluate wastewater inputs from land-based sources to habitats which are sensitive to changing water quality, like coral reefs.
Показать больше [+] Меньше [-]PCDD/Fs in soil and air and their possible sources in the vicinity of municipal solid waste incinerators in northeastern China Полный текст
2016
Meng, Bo | Ma, Wanli | Liu, Li-Yan | Zhu, Ning-Zheng | Song, Wei-Wei | Lo, Ching Yee | Li, James | Kannan, Kurunthachalam | Li, Yi-Fan
Fly ash, flue gas, ambient air, and soil samples were collected to investigate concentrations, profiles, gas–particle partitioning, and air–soil exchange of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the vicinity of two municipal solid waste incinerators (MSWIs) in Harbin in northeastern China. The PCDD/F concentrations were 11 600–12 300 pg g−1 (597–615 pg WHO-TEQ g−1) in fly ash and 873–1120 fg m−3 (51.2–61.9 fg WHO-TEQ m−3) in air. The results of gas–particle partitioning possibly indicated the equilibrium state of PCDD/F during sampling period. For soil samples, both Enzyme-linked immuno-sorbent assay (ELISA) and high-resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) were used. Significant correlations between the results from these two methods indicated that both methods are useful for PCDD/Fs analysis in soil. PCDD/Fs concentrations in soil samples ranged from 17.2 to 157 pg g−1 (0.59–8.81 pg WHO-TEQ g−1). Both Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) suggested the sources of the emission from MSWIs and the historical emission from a petroleum refinery to PCDD/Fs in adjacent soils. The air–soil exchange analysis showed a net flux of PCDD/F from air to soil at all soil-sampling sites.
Показать больше [+] Меньше [-]Bioremediation technologies for polluted seawater sampled after an oil-spill in Taranto Gulf (Italy): A comparison of biostimulation, bioaugmentation and use of a washing agent in microcosm studies Полный текст
2016
Crisafi, F. | Genovese, M. | Smedile, F. | Russo, D. | Catalfamo, M. | Yakimov, M. | Giuliano, L. | Denaro, R.
One of the main challenges of bioremediation is to define efficient protocols having a low environmental impact. We have investigated the effect of three treatments in oily-seawater after a real oil-spill occurred in the Gulf of Taranto (Italy). Biostimulation with inorganic nutrients allowed the biodegradation of the 73±2.4% of hydrocarbons, bioaugmentation with a selected hydrocarbonoclastic consortium consisting of Alcanivorax borkumensis, Alcanivorax dieselolei, Marinobacter hydrocarbonoclasticus, Cycloclasticus sp. 78-ME and Thalassolituus oleivorans degraded 79±3.2%, while the addition of nutrients and a washing agent has allowed the degradation of the 69±2.6%. On the other hand, microbial community was severely affected by the addition of the washing agent and the same product seemed to inhibit the growth of the majority of strains composing the selected consortium at the tested concentration. The use of dispersant should be accurately evaluated also considering its effect on the principal actors of biodegradation.
Показать больше [+] Меньше [-]FTIR spectroscopy supported by statistical techniques for the structural characterization of plastic debris in the marine environment: Application to monitoring studies Полный текст
2016
Mecozzi, Mauro | Pietroletti, Marco | Monakhova, Yulia B.
We inserted 190 FTIR spectra of plastic samples in a digital database and submitted it to Independent Component Analysis (ICA) to extract the “pure” plastic polymers present. These identified plastics were polypropylene (PP), high density polyethylene (HDPE), low density polyethylene (LDPE), high density polyethylene terephthalate (HDPET), low density polyethylene terephthalate (LDPET), polystyrene (PS), Nylon (NL), polyethylene oxide (OPE), and Teflon (TEF) and they were used to establish the similarity with unknown plastics using the correlation coefficient (r), and the crosscorrelation function (CC). For samples with r<0.8 we determined the Mahalanobis Distance (MD) as additional tool of identification. For instance, for the four plastic fragments found in the Carretta carretta, one plastic sample was assigned to OPE due to its r=0.87; for all the other three plastic samples, due to the r values ranging between 0.83 and0.70, the support of MD suggested LDPET and OPE as co-polymer constituents.
Показать больше [+] Меньше [-]Rare Earth Elements in the Soil Environment Полный текст
2016
Ramos, Silvio J. | Dinali, Guilherme S. | Oliveira, Cynthia | Martins, Gabriel C. | Moreira, Cristiano G. | Siqueira, José O. | Guilherme, Luiz R. G.
Rare earth elements (REE) are a homogenous group of 17 chemical elements in the periodic table that are key to many modern industries including chemicals, consumer electronics, clean energy, transportation, health care, aviation, and defense. Moreover, in recent years, they have been used in agriculture. One of the consequences of their worldwide use is the possible increase of their levels in various environmental compartments. This review addresses major topics concerning the study of REE in the soil environment, with special attention to the latest research findings. The main sources of REE to soils, the contents of REE in soils worldwide, and relevant information on the effects of REE to plants were explored. Ecological and human health risk issues related to the presence of REE in soils were also discussed. Although several findings reported positive effects of REE on plant growth, many questions about their biological role remain unanswered. Therefore, studies concerning the actual mechanism of action of these elements on cellular and physiological processes should be further refined. Even more urgent is to unveil their chemical behavior in soils and the ecological and human health risks that might be associated with the widespread use of REE in our modern society.
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