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ALien Biotic IndEX (ALEX) – A new index for assessing impacts of alien species on benthic communities
2014
Çinar, Melih Ertan | Bakir, Kerem
Biotic indices are mainly aimed at assessing levels of deterioration caused by chemical or organic pollution. However, no biotic index to date has been developed to detect impacts of alien species on benthic communities. In this paper, a new biotic index, namely ALEX, is proposed to address the objectives of the Water Framework Directive and was tested in Mersin Bay (Levantine Sea, Turkey). Species were divided into four biogeographic groups, namely native species, casual species, established species and invasive species, and the metric considers the relative importance of these groups in samples. The index classified the ecological status of some stations which are shallow, and close to harbor and river mouths as bad or poor in February and October. The ALEX values were positively and significantly correlated with total nitrogen, silicate and silt percentage in sediment, and negatively correlated with depth and the distance from the harbor.
Mostrar más [+] Menos [-]A multivariate approach to the determination of an indicator species pool for community-based bioassessment of marine water quality
2014
Xu, Guangjian | Zhong, Xiaoxiao | Wang, Yangfan | Warren, Alan | Xu, Henglong
Previous studies in Chinese coastal waters of the Yellow Sea have shown that periphytic ciliates are reliable indicators of marine water quality. However, traditional community-based bioassessments are time-consuming because they rely on the identification and enumeration of all species within the community. In order to improve bioassessment efficiency, step-best-matching analysis was used to identify which are the most reliable indicator species among periphytic marine ciliate communities. Based on indices of species richness, diversity and evenness, a subset of 48 species (out of a total of 141) was found to retain sufficient information for accurately predicting water quality, and was more strongly related to changes of environmental variables than the full species set. These results demonstrate that the step-best-matching analysis is a powerful approach for identifying an indicator species pool from a full species dataset of a community, and allows the development of time-efficient sampling protocols for community-based marine bioassessment.
Mostrar más [+] Menos [-]A comparative study of marine litter on the seafloor of coastal areas in the Eastern Mediterranean and Black Seas
2014
Ioakeimidis, C. | Zeri, C. | Kaberi, H. | Galatchi, M. | Antoniadis, K. | Streftaris, N. | Galgani, F. | Papathanassiou, E. | Papatheodorou, G.
In the present work, abundance, spatial distribution and qualitative composition, of benthic marine litter, were investigated in five study areas from the Eastern Mediterranean and Black Seas (Saronikos, Patras and Echinades Gulfs; Limassol Gulf; Constanta Bay). Surveys were performed using the monitoring protocol proposed by the Technical Group for Marine Litter. Densities ranged from 24items/km2 to 1211items/km2, with the Saronikos Gulf being the most affected area. Plastics were predominant in all study areas ranging from 45.2% to 95%. Metals and Glass/Ceramics reached maximum values of 21.9% and of 22.4%. The size distribution of litter items showed that ⩾50% fall into medium size categories (10×10cm, 20×20cm) along with an elevated percentage of small-sized (<5×5cm) plastic litter items. The comparative analysis of the data highlighted the dependence of the marine litter problem on many local factors (human sources and oceanographic conditions) and the urgent need for specific actions.
Mostrar más [+] Menos [-]Patterns of marine debris distribution on the beaches of Rottnest Island, Western Australia
2014
Smith, Stephen D.A. | Gillies, Chris L. | Shortland-Jones, Helen
Rottnest Island, Western Australia, receives >500,000visitorsy−1, who are mainly attracted by the Island’s natural values. Marine debris is a threat to both these natural values and to Island wildlife, and is consequently an important issue for managers. Engaging with volunteers, we quantified marine debris at 16 beach sites around the Island. The highest loads occurred on the SW coast and primarily comprised items originating from fishing activities. Sites on the NE coast, where >95% of the Island’s accommodation is located, supported the highest abundance of items deposited in situ (e.g. bottles and cigarette butts). We conclude that marine debris management may require a range of strategies to address the different primary sources. Raising awareness through education and intervention may be highly effective at popular beaches on the NE coast, but broader liaison with commercial and recreational fishers will be necessary to address the issue at the Island scale.
Mostrar más [+] Menos [-]Regional distribution of halogenated organophosphate flame retardants in seawater samples from three coastal cities in China
2014
Hu, Mengyang | Li, Jun | Zhang, Beibei | Cui, Qinglan | Wei, Si | Yu, Hongxia
Thirteen samples of seawater were collected from Yellow Sea and East China Sea near Qingdao, Lianyungang, and Xiamen, China. They were analyzed for halogenated organophosphorus flame retardants (OPFRs). The compounds selected for detection were Tris(2-chloroethyl) phosphate (TCEP), Tris(2-chloroisopropyl) phosphate (TCPP), Tris (1,3-dichloro-2-propyl) phosphate (TDCPP), and Tris(2,3-dibromopropyl) phosphate (TDBPP). The total concentrations ranged from 91.87 to 1392ng/L and the mean concentrations of these four chemicals were 134.44, 84.12, 109.28, and 96.70ng/L, respectively. TCEP exhibited the highest concentrations, although concentrations of TCPP and TDCPP were also fairly high in Lianyungang and Xiamen. Generally, Lianyungang was the most heavily polluted district, with very high concentrations of TCEP at LYG-2 (550.54ng/L) and LYG-4 (617.92ng/L). The main sources of halogenated OPFRs were municipal and industrial effluents of wastewater treatment plants in the nearby economic and industrial zones.
Mostrar más [+] Menos [-]Interannual changes in δ15N values in Fucus vesiculosus L
2014
Carballeira, Carlos | Rey-Asensio, Ana | Carballeira, Alejo
The natural abundance of 15N (δ15N) has been widely used to detect anthropogenically derived N loads in environmental impact studies. The present study involved retrospective analysis of subsamples of Fucus vesiculosus L. collected during a period of three years (2008–2010) from two sites: a control site, within a coastal reference area, and an area affected by the effluents of a marine land-based fish farm. The isotopic signal in different subsamples of the macroalgae thalli (tissue that has grown during the same period) varied depending on the age of the tissue. Moreover, the isotopic signal decreased significantly with the age of the frond to within a certain range. The δ15N of F. vesiculosus is temporally unstable; therefore, measurement of the δ15N of macroalgal tissues does not allow reliable retrospective biomonitoring of environmental pollution. Further knowledge about the growth and other biological aspects of this species is required.
Mostrar más [+] Menos [-]Assessing weathered Endicott oil biodegradation in brackish water
2014
Personna, Yves Robert | King, Thomas | Boufadel, Michel C. | Zhang, Shuangyi | Kustka, Adam
We evaluated the biodegradability of physically (WAF) and chemically (CEWAF) dispersed oil in brackish water (salinity ∼6.5g/L), and the influence of nutrient availability (low nutrient-LN: background water vs. high nutrient-HN: addition of 100mgNO3-N/L and 10mg PO4-P/L to background water) on oil biodegradation rates at 15±0.5°C for 42days. No oil removal occurred in WAF compared with CEWAF: 24% in HN and 14% in LN within two weeks. The oil biodegradation concerned mainly alkanes as confirmed by GC/MS analyses. Higher O2 consumption (10.30mgL−1day−1) and CO2 production (3.89mg CL−1day−1) were measured in HN compared with LN (O2: 2.79mgL−1day−1, CO2:0.18mg CL−1day−1). Estimated biomass of hydrocarbon degraders and heterotrophic bacteria was at least an order of magnitude larger in HN than in LN. Combining dispersants with nutrients could enhance oil biodegradation and help improve oil spill mitigation responses.
Mostrar más [+] Menos [-]Evaluation of phytotoxicity of seaport sediments aged artificially by rotary leaching in the framework of a quarry deposit scenario
2014
Bedell, J.-P. | Ferro, Y. | Bazin, C. | Perrodin, Y.
In the framework of an ecological risk assessment of seaport sediments for terrestrial ecosystems when deposited in quarries, we simulated the “ageing” of sediments exposed to rain. This experiment highlighted an inflection point at the solid/liquid ratio 1/25, after which the extraction of pollutants increases moderately. The raw sediments studied inhibited the germination of Lolium perenne and Armeria maritima (a halophytic species) seeds. Furthermore, they affected the early development of L.perenne. The same sediments, leached at a ratio of 1/25, presented a reduction of acute (germination) and chronic (growth) phytotoxicity. The bioconcentration factors of the metals studied decreased with the leached sediment, except for Cu which was still clearly identified in root parts. Thus rotary leaching tests and phytotoxicity bioassays can be used to provide an initial assessment of the ability of plants, particularly halophytes, to colonize deposits of dredged seaport sediments.
Mostrar más [+] Menos [-]Review of oil spill remote sensing
2014
Fingas, Mervin F. | Brown, Carl
Remote-sensing for oil spills is reviewed. The use of visible techniques is ubiquitous, however it gives only the same results as visual monitoring. Oil has no particular spectral features that would allow for identification among the many possible background interferences. Cameras are only useful to provide documentation. In daytime oil absorbs light and remits this as thermal energy at temperatures 3–8K above ambient, this is detectable by infrared (IR) cameras.Laser fluorosensors are useful instruments because of their unique capability to identify oil on backgrounds that include water, soil, weeds, ice and snow. They are the only sensor that can positively discriminate oil on most backgrounds. Radar detects oil on water by the fact that oil will dampen water-surface capillary waves under low to moderate wave/wind conditions. Radar offers the only potential for large area searches, day/night and foul weather remote sensing.
Mostrar más [+] Menos [-]Assessment of pollution in the Bizerte lagoon (Tunisia) by the combined use of chemical and biochemical markers in mussels, Mytilus galloprovincialis
2014
Barhoumi, Badreddine | Menach, Karyn Le | Clérandeau, Christelle | Ameur, Walid Ben | Budzinski, Hélène | Driss, Mohamed Ridha | Cachot, Jérôme
In order to assess the environmental quality of the Bizerte lagoon (Tunisia), biomarker and contaminant levels were measured in Mediterranean mussels (Mytilus galloprovincialis) from five selected sites. Persistent organic pollutants (POPs) were quantified in whole body and enzyme activities such as acetylcholinesterase (AChE), catalase (CAT) and glutathione S-transferase (GST) in gills. Despite the relatively low levels of organic contaminants, the selected biomarkers responded differently according to the pollution level at the different sites. GST and AChE activities were correlated with the amount of DDTs in mussel tissues. These two enzymatic activities were also correlated to temperature and pH. No significant difference was observed for CAT activity. Principal component analysis showed a clear separation of sampling sites in three different assemblages which is consistent with POP body burden in mussels. Our results confirmed the usefulness of combining biomarker and chemical analyses in mussels to assess chemical pollution in the Bizerte lagoon.
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