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Hazardous and Noxious Substances (HNS) in the marine environment: Prioritizing HNS that pose major risk in a European context Полный текст
2011
Neuparth, T. | Moreira, S. | Santos, M.M. | Reis-Henriques, M.A.
Increases in the maritime transportation of Hazardous and Noxious Substances (HNS), alongside the need for an effective response to HNS spills have led environmental managers and the scientific community to focus attention on HNS spill preparedness and responsiveness. In the context of the ARCOPOL project, a weight-of-evidence approach was developed aimed at prioritizing HNS that pose major environmental risks to European waters. This approach takes into consideration the occurrence probability of HNS spills in European Atlantic waters and the severity of exposure associated with their physico-chemical properties and toxicity to marine organisms. Additionally, a screening analysis of the toxicological information available for the prioritization of HNS was performed. Here we discuss the need for a prioritization methodology to select HNS that are likely to cause severe marine environmental effects as an essential step towards the establishment of a more effective preparedness and response to HNS incidents.
Показать больше [+] Меньше [-]Molecular ecological responses of dinoflagellate, Karenia mikimotoi to environmental nitrate stress Полный текст
2011
Lei, Qiang-Yong | Lü, Song-Hui
Karenia mikimotoi is one of the most important harmful algal species in the Chinese coastal waters, and which produce hemolytic toxins and ichthyotoxins, resulting in devastating economic losses. Previous studies demonstrated that the increase of nitrate concentration could promote the growth and reproduction of K. mikimotoi. However, the intrinsic mechanisms regarding the effects of nitrate on the K. mikimotoi photosynthesis, nucleic acid replication and differential protein expression remain to be elucidated. Our study demonstrated that nitrate stress inhibited growth of K. mikimotoi (p<0.01). Algal chlorophyll fluorescence intensity varied slightly while algal cell cycle succession was significantly retarded by nitrate stress (p<0.05). Sixteen proteins were detected only in nitrate-limited cultures which related to nitrate transport, signal transduction, amino acid metabolism, DNA repair and hemolysin manufacture. Eleven proteins were detected only in nitrate-replete sample and were related to photorespiration, reproduction and growth, assistance of protein modification, cytoskeleton stability and signal transduction. Based on analysis of differential proteomic functional annotations, we hypothesized a proteomic response mechanism of K. mikimotoi to environmental nitrate stress.
Показать больше [+] Меньше [-]Mussel farming as a nutrient reduction measure in the Baltic Sea: Consideration of nutrient biogeochemical cycles Полный текст
2011
Stadmark, J. | Conley, D.J.
Nutrient loads from the land to the sea must be reduced to combat coastal eutrophication. It has been suggested that further mitigation efforts are needed in the brackish Baltic Sea to decrease nutrients, especially in eutrophic coastal areas. Mussel farming is a potential measure to remove nutrients directly from the sea. Mussels consume phytoplankton containing nitrogen (N) and phosphorus (P); when the mussels are harvested these nutrients are removed from the aquatic system. However, sedimentation of organic material in faeces and pseudo-faeces below a mussel farm consumes oxygen and can lead to hypoxic or even anoxic sediments causing an increased sediment release of ammonium and phosphate. Moreover, N losses from denitrification can be reduced due to low oxygen and reduced numbers of bioturbating organisms. To reveal if mussel farming is a cost-effective mitigation measure in the Baltic Sea the potential for enhanced sediment nutrient release must be assessed.
Показать больше [+] Меньше [-]The impact of dredge-fill on Posidonia oceanica seagrass meadows: Regression and patterns of recovery Полный текст
2011
Badalamenti, Fabio | Alagna, Adriana | D’Anna, Giovanni | Terlizzi, Antonio | Di Carlo, Giuseppe
Posidonia oceanica meadows can be severely damaged by dredge-fill operations. We report on the construction of gas pipelines that occurred between 1981 and 1993 in SW Sicily, Italy. A large portion of the meadow was mechanically removed, and the excavated trench was filled with a mosaic of substrates, ranging from sand to consolidated rock debris. Meadow loss and recovery were quantified over 7years after the end of operations. We recorded an overall loss of 81.20ha of meadow. Substrate strongly affected recovery as the percent cover by P. oceanica consistently increased on calcareous rubble, reaching values of 44.37±3.05% in shallow sites after 7years, whereas no significant increase occurred on other substrates. As in the Mediterranean Sea exploitation of coastal areas continues to grow with consequent impacts on P. oceanica meadows, this case study illustrates how artificial rubble-like materials could be employed to support the restoration of damaged meadows.
Показать больше [+] Меньше [-]Response of single benthic metrics and multi-metric methods to anthropogenic pressure gradients, in five distinct European coastal and transitional ecosystems Полный текст
2011
Borja, Angel | Barbone, Enrico | Basset, Alberto | Borgersen, Gunhild | Brkljacic, Marijana | Elliott, Michael | Garmendia, Joxe Mikel | Marques, João Carlos | Mazik, K. (Krysia) | Muxika, Iñigo | Neto, João Magalhães | Norling, Karl | Rodríguez, J Germán | Rosati, Ilaria | Rygg, Brage | Teixeira, Heliana | Trayanova, Antoaneta
In recent times many benthic indices have been proposed to assess the ecological quality of marine waters worldwide. In this study we compared single metrics and multi-metric methods to assess coastal and transitional benthic status along human pressure gradients in five distinct environments across Europe: Varna bay and lake (Bulgaria), Lesina lagoon (Italy), Mondego estuary (Portugal), Basque coast (Spain) and Oslofjord (Norway). Hence, 13 single metrics (abundance, number of taxa, and several diversity and sensitivity indices) and eight of the most common indices used within the European Water Framework Directive (WFD) for benthic assessment were selected: index of size spectra (ISS), Benthic assessment tool (BAT), Norwegian quality index (NQI), Multivariate AMBI (M-AMBI), Benthic quality index (BQI), (Benthic ecosystem quality index (BEQI), Benthic index based on taxonomic sufficiency (BITS), and infaunal quality index (IQI). Within each system, sampling sites were ordered in an increasing pressure gradient according to a preliminary classification based on professional judgement. The different indices are largely consistent in their response to pressure gradient, except in some particular cases (i.e. BITS, in all cases, or ISS when a low number of individuals is present). Inconsistencies between indicator responses were most pronounced in transitional waters (i.e. IQI, BEQI), highlighting the difficulties of the generic application of indicators to all marine, estuarine and lagoonal environments. However, some of the single (i.e. ecological groups approach, diversity, richness) and multi-metric methods (i.e. BAT, M-AMBI, NQI) were able to detect such gradients both in transitional and coastal environments, being these multi-metric methods more consistent in the detection than single indices. This study highlights the importance of survey design and good reference conditions for some indicators. The agreement observed between different methodologies and their ability to detect quality trends across distinct environments constitutes a promising result for the implementation of the WFD’s monitoring plans. Moreover, these results have management implications, regarding the dangers of misclassification, uncertainty in the assessment, use of conflicting indices, and testing and validation of indices.
Показать больше [+] Меньше [-]Seasonal variations of imposex indices and butyltin concentrations in the rock shell Thais clavigera collected from Hong Kong waters Полный текст
2011
Qiu, Jian-Wen | Chan, Ka Ming | Leung, Kenneth Mei Yee
This study investigated butyltin contamination in Hong Kong waters using the rock shell Thais clavigera as a biomonitor. We collected rock shells from nine coastal sites in both winter 2005 and summer 2006 to examine the spatial and seasonal patterns. The relative penis size index (RPSI) and vas deferens sequence index (VDSI) were determined following a standard protocol, while the tissue concentrations of butyltins (i.e., mono-, di- and tri-butyltin) were measured using gas chromatography. The results showed that imposex was particularly severe in T. clavigera collected from Victoria Harbour, Pak Sha Wan and Sai Kung Pier where shipping activities were frequent. Both imposex indices had a positive correlation with tissue concentration of tributyltin in T. clavigera. While VDSI exhibited little seasonal variation, RPSI of winter specimens was significantly higher than that of summer specimens. Thus, sampling season should be standardised when using RPSI as a biomarker.
Показать больше [+] Меньше [-]Spatial and temporal distribution of heavy metal concentrations in mussels (Mytilus edulis) from the Baie des Chaleurs, New Brunswick, Canada Полный текст
2011
Fraser, Marc | Surette, Céline | Vaillancourt, Cathy
Previous studies on heavy metal contamination of the Baie des Chaleurs focus only on industrial centers and overlooked the ecosystem as a whole. To fill this gap, the objective of this study is to establish a baseline of the spatio-temporal distribution of heavy metals in mussels from the Baie des Chaleurs based on the ecosystem approach. Our results show, for the first time, a cadmium contamination in mussels across the south coast of the Baie des Chaleurs and not only in industrial centers. Our results also confirm previous studies showing heavy metal contamination of the Belledune area. This study demonstrates that the use of the ecosystemic approach is essential to obtain a comprehensive picture of environmental contamination in marine ecosystems.
Показать больше [+] Меньше [-]Monitoring of organic contaminants in sediments from the Korean coast: Spatial distribution and temporal trends (2001–2007) Полный текст
2011
Choi, Hee Gu | Moon, Hyo Bang | Choi, Minkyu | Yu, Jun
Spatial and temporal trends of organic contaminants in sediments along the Korean coast were estimated through a nationwide environmental monitoring program from 2001 to 2007. The concentrations of organic contaminants in sediments along the Korean coast were relatively low or moderate compared with foreign studies. The mean detection frequencies of organic contaminants during the seven years were highest for PAHs and PCDD/Fs, followed by PCBs, DDTs, TBT and HCHs in decreasing order. Based on published sediment quality guidelines, the ecological risks of persistent organic pollutants in sediments along the Korean coast were low, despite exceedances of the ERL at 2–6 sites for DDTs, and the TEL at 9–18 sites for PCDD/Fs. Nonparametric tests to assess temporal trends revealed significant decreasing trends for PCBs and PCDD/Fs at four and three sites, respectively (p<0.05). These results reflect the effects of regulations on the use of those contaminants.
Показать больше [+] Меньше [-]Gillnet fisheries as a major mortality factor of Magellanic penguins in wintering areas Полный текст
2011
Cardoso, Luis Gustavo | Bugoni, Leandro | Mancini, Patrícia Luciano | Haimovici, Manuel
The incidental capture in fisheries is probably the main conservation problem affecting seabirds. While the capture of albatrosses and petrels on longline hooks is well-known worldwide, the bycatch of diving seabirds in gillnets is an overlooked conservation problem. During a winter coastal fishing trip, the capture of Magellanic penguins (Spheniscus magellanicus) was recorded in driftnet and bottom setnet fisheries for the first time in southern Brazil. The highest captures rates were found in driftnets, from 146.5 to 545.5penguins/km² of net and a total of 56 dead penguins were recorded. In the bottom gillnet, a total of 12 birds were killed and the capture rates varied from 41.7 to 125.0penguins/km² of net. Although preliminary, the results presented in this paper were consistent between sets. If we consider the magnitude of driftnet and setnet fishing fleets, and that most dead penguins were adults, the impact upon Magellanic penguin populations is probably significant.
Показать больше [+] Меньше [-]Hydrocarbon composition and distribution in a coastal region under influence of oil production in northeast Brazil Полный текст
2011
Wagener, Angela de L.R. | Carreira, Renato S. | Hamacher, Claudia | Scofield, Arthur de L. | Farias, Cassia O. | Cordeiro, Lívia G.M.S. | Luz, Letícia G. | Baêta, Aída P. | Kalas, Francine A.
Waters and sediments from the Potiguar Basin (NE Brazilian coast) were investigated for the presence and nature of polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons. The region receives treated produced waters through a submarine outfall system serving the industrial district. The total dispersed/dissolved concentrations in the water column ranged from 10–50ngL⁻¹ for ∑16PAH and 5–10μgL⁻¹ for total aliphatic hydrocarbons. In the sediments, hydrocarbon concentrations were low (0.5–10ngg⁻¹for ∑16PAH and 0.01–5.0μgg⁻¹ for total aliphatic hydrocarbons) and were consistent with the low organic carbon content of the local sandy sediments. These data indicate little and/or absence of anthropogenic influence on hydrocarbon distribution in water and sediment. Therefore, the measured values may be taken as background values for the region and can be used as future reference following new developments of the petroleum industry in the Potiguar Basin.
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