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Seasonal variations of biomarker responses in the marine blue mussel (Mytilus spp.) Полный текст
2013
Schmidt, Wiebke | Power, Emma | Quinn, Brian
Biomarkers, which can detect changes at the biochemical level, have been used for many years as early warning tools in environmental monitoring. In order to distinguish between natural variability and the potential effects of anthropogenic pollution, it is essential to identify background levels and establish the potential influence of abiotic (season, temperature and salinity) and biotic (gametogenesis) factors. In this study, we examined various biomarkers of stress (glutathione S-transferase (GST)), reproduction (vitellin-like proteins) and damage (lipid peroxidation (LPO) and DNA damage (DNA)) in marine mussels (Mytilus spp.) from a known pristine hybrid zone. Levels of all biomarker expression varied between seasons and appeared to be linked to the reproductive cycle. Oxidative stress in winter, with low GST expression and a higher expression of LPO and DNA damage displayed could be explained by low food availability. These data provide vital baseline information for future ecotoxicological and environmental monitoring studies.
Показать больше [+] Меньше [-]Physical dynamics controlling variability in nearshore fecal pollution: Fecal indicator bacteria as passive particles Полный текст
2013
Rippy, M.A. | Franks, P.J.S. | Feddersen, F. | Guza, R.T. | Moore, D.F.
We present results from a 5-h field program (HB06) that took place at California’s Huntington State Beach. We assessed the importance of physical dynamics in controlling fecal indicator bacteria (FIB) concentrations during HB06 using an individual based model including alongshore advection and cross-shore variable horizontal diffusion. The model was parameterized with physical (waves and currents) and bacterial (Escherichia coli and Enterococcus) observations made during HB06. The model captured surfzone FIB dynamics well (average surfzone model skill: 0.84 {E. coli} and 0.52 {Enterococcus}), but fell short of capturing offshore FIB dynamics. Our analyses support the hypothesis that surfzone FIB variability during HB06 was a consequence of southward advection and diffusion of a patch of FIB originating north of the study area. Offshore FIB may have originated from a different, southern, source. Mortality may account for some of the offshore variability not explained by the physical model.
Показать больше [+] Меньше [-]An integrative method for the evaluation, monitoring, and comparison of seagrass habitat structure Полный текст
2013
Irving, Andrew D. | Tanner, Jason E. | Gaylard, Sam G.
An integrative method for the evaluation, monitoring, and comparison of seagrass habitat structure Полный текст
2013
Irving, Andrew D. | Tanner, Jason E. | Gaylard, Sam G.
Assessing environmental condition is essential for the management of coasts and their resources, but better management decisions occur when large databases are simplified into more manageable units of information. Here we present the habitat structure index (HSI), which enables rapid assessment and direct comparison of seagrass habitat structure using scores of 0 (poor) to 100 (excellent) based on integrating five habitat variables: area, continuity, proximity, percentage cover, and species identity. Acquiring data to calculate the HSI can be done in situ or from video recordings, and requires relatively simple methodology of belt transects, estimating percentage cover, and basic taxonomy. Spatiotemporal comparisons can usefully identify locations and periods of seagrass habitat change, potentially providing an early warning indicator of habitat damage and decline in environmental quality. Overall, the integrative approach of the HSI represents a step toward simplifying the exchange of environmental information among researchers, coastal managers, and governing bodies.
Показать больше [+] Меньше [-]An integrative method for the evaluation, monitoring, and comparison of seagrass habitat structure Полный текст
2013
Irving, A. | Tanner, J. | Gaylard, S.
Abstract not available | Andrew D. Irving, Jason E. Tanner, Sam G. Gaylard
Показать больше [+] Меньше [-]An ‘extreme’ future for estuaries? Effects of extreme climatic events on estuarine water quality and ecology Полный текст
2013
Wetz, Michael S. | Yoskowitz, David W.
Recent climate observations suggest that extreme climatic events (ECE; droughts, floods, tropical cyclones, heat waves) have increased in frequency and/or intensity in certain world regions, consistent with climate model projections that account for man’s influence on the global climate system. A synthesis of existing literature is presented and shows that ECE affect estuarine water quality by altering: (1) the delivery and processing of nutrients and organic matter, (2) physical–chemical properties of estuaries, and (3) ecosystem structure and function. From the standpoint of estuarine scientists and resource managers, a major scientific challenge will be to project the estuarine response to ECE that will co-occur with other important environmental changes (i.e., natural climate variability, global warming, sea level rise, eutrophication), as this will affect the provisioning of important ecosystem services provided by estuaries.
Показать больше [+] Меньше [-]Trace metal contamination of the aquatic plant Hydrilla verticillata and associated sediment in a coastal Alabama creek (Gulf of Mexico – USA) Полный текст
2013
Lafabrie, C. | Major, K.M. | Major, C.S. | Cebrián, J.
The objectives of this study were to (i) assess trace metal concentrations in Hydrilla verticillata and sediment from an estuarine creek in Alabama (USA), where high metal levels in biota were previously reported, and (ii) investigate the relationship between metal concentrations in H. verticillata and the sediment compartment. Our results indicate that sediment and H. verticillata exhibit moderate metal concentrations in the study area. We found that levels in plant tissues can be up to five times higher than in the sediment (e.g., Cd), suggesting that H. verticillata can take up and store several trace metals (Cd, Hg, Ni, and Zn) from this compartment. Together with studies focused on the uptake and accumulation of trace metals from the surrounding water, laboratory- and field-based studies are needed to better evaluate this plant’s ability to acquire metals from the sediment that constitutes a contaminant sink in human-impacted coastal regions.
Показать больше [+] Меньше [-]Chemometric evaluation of the heavy metals distribution in waters from the Dilovası region in Kocaeli, Turkey Полный текст
2013
Bingöl, Deniz | Ay, Ümit | Karayünlü Bozbaş, Seda | Uzgören, Nevin
The main objective of this study was to test water samples collected from 10 locations in the Dilovası area (a town in the Kocaeli region of Turkey) for heavy metal contamination and to classify the heavy metal (Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Pb and Hg) contents in water samples using chemometric methods. The heavy metals in the water samples were identified using inductively coupled plasma-mass spectrometry (ICP-MS). To ascertain the relationship among the water samples and their possible sources, the correlation analysis, principal component analysis (PCA), and cluster analysis (CA) were used as classification techniques. About 10 water samples were classified into five groups using PCA. A very similar grouping was obtained using CA.
Показать больше [+] Меньше [-]Coastal urbanization leads to remarkable seaweed species loss and community shifts along the SW Atlantic Полный текст
2013
Scherner, Fernando | Horta, Paulo Antunes | de Oliveira, Eurico Cabral | Simonassi, José Carlos | Hall-Spencer, Jason M. | Chow, Fungyi | Nunes, José Marcos C. | Pereira, Sonia Maria Barreto
Coastal urbanization leads to remarkable seaweed species loss and community shifts along the SW Atlantic Полный текст
2013
Scherner, Fernando | Horta, Paulo Antunes | de Oliveira, Eurico Cabral | Simonassi, José Carlos | Hall-Spencer, Jason M. | Chow, Fungyi | Nunes, José Marcos C. | Pereira, Sonia Maria Barreto
Coastal urbanization is rapidly expanding worldwide while its impacts on seaweed communities remain poorly understood. We assessed the impact of urbanization along an extensive latitudinal gradient encompassing three phycogeographical regions in the SW Atlantic. Human population density, number of dwellings, and terrestrial vegetation cover were determined for each survey area and correlated with diversity indices calculated from seaweed percent cover data. Urban areas had significantly lower calcareous algal cover (−38%), and there was significantly less carbonate in the sediment off urban areas than off reference areas. Seaweed richness averaged 26% less in urban areas than in areas with higher vegetation cover. We observed a remarkable decline in Phaeophyceae and a substantial increase of Chlorophyta in urban areas across a wide latitudinal gradient. Our data show that coastal urbanization is causing substantial loss of seaweed biodiversity in the SW Atlantic, and is considerably changing seaweed assemblages.
Показать больше [+] Меньше [-]Coastal urbanization leads to remarkable seaweed species loss and community shifts along the SW Atlantic | Marine Pollution Bulletin Полный текст
2013
Scherner, Fernando | Horta, Paulo Antunes | Oliveira, Eurico Cabral de | Simonassi, José Carlos | Hall Spencer, Jason M. | Chow, Fungyi | Nunes, José Marcos de Castro | Pereira, Sônia Maria Barreto | Scherner, Fernando | Horta, Paulo Antunes | Oliveira, Eurico Cabral de | Simonassi, José Carlos | Hall Spencer, Jason M. | Chow, Fungyi | Nunes, José Marcos de Castro | Pereira, Sônia Maria Barreto
Texto completo: acesso restrito. p. 106–115 | Coastal urbanization is rapidly expanding worldwide while its impacts on seaweed communities remain poorly understood. We assessed the impact of urbanization along an extensive latitudinal gradient encompassing three phycogeographical regions in the SW Atlantic. Human population density, number of dwellings, and terrestrial vegetation cover were determined for each survey area and correlated with diversity indices calculated from seaweed percent cover data. Urban areas had significantly lower calcareous algal cover (−38%), and there was significantly less carbonate in the sediment off urban areas than off reference areas. Seaweed richness averaged 26% less in urban areas than in areas with higher vegetation cover. We observed a remarkable decline in Phaeophyceae and a substantial increase of Chlorophyta in urban areas across a wide latitudinal gradient. Our data show that coastal urbanization is causing substantial loss of seaweed biodiversity in the SW Atlantic, and is considerably changing seaweed assemblages.
Показать больше [+] Меньше [-]Plastic ingestion in marine-associated bird species from the eastern North Pacific Полный текст
2013
Avery-Gomm, S. | Provencher, J.F. | Morgan, K.H. | Bertram, D.F.
In addition to monitoring trends in plastic pollution, multi-species surveys are needed to fully understand the pervasiveness of plastic ingestion. We examined the stomach contents of 20 bird species collected from the coastal waters of the eastern North Pacific, a region known to have high levels of plastic pollution. We observed no evidence of plastic ingestion in Rhinoceros Auklet, Marbled Murrelet, Ancient Murrelet or Pigeon Guillemot, and low levels in Common Murre (2.7% incidence rate). Small sample sizes limit our ability to draw conclusions about population level trends for the remaining fifteen species, though evidence of plastic ingestion was found in Glaucous-Winged Gull and Sooty Shearwater. Documenting levels of plastic ingestion in a wide array of species is necessary to gain a comprehensive understanding about the impacts of plastic pollution. We propose that those working with bird carcasses follow standard protocols to assess the levels of plastic ingestion whenever possible.
Показать больше [+] Меньше [-]Metals contamination along the watershed and estuarine areas of southern Bohai Sea, China Полный текст
2013
Xu, Li | Wang, Tieyu | Ni, Kun | Liu, Shijie | Wang, Pei | Xie, Shuangwei | Meng, Jing | Zheng, Xiaoqi | Lü, Yonglong
Distributions and magnitude of metals in water, sediment and soil collected from the watershed and estuarine areas of southern Bohai Sea, were investigated. The largest dissolved concentrations of As, Cu and Zn in water were 347.70, 2755.00, 2076.00μg/L, respectively, much higher than corresponding drinking water guidelines. The greatest concentrations of Cu, Zn, Cr, Ni, Pb, As and Cd in sediments were 1462.2, 1602.17, 196.43, 67.15, 63.54, 73.86 and 1.41mg/kg, dw, respectively. The mean concentrations of Cu, Ni, Cd, Zn, Cr, Pb and As in soils were 24.67, 24.73, 0.14, 64.75, 56.52, 25.12 and 9.34mg/kg, dw, respectively. Land use was confirmed to be an important factor of influence on soil metal concentrations. Metal contents along the watershed of Jie River were significantly greater than in other locations. The detection of metals in relatively high concentrations from different environmental matrices in this region indicates the necessity of further studies.
Показать больше [+] Меньше [-]Investigation of priorities in water quality management based on correlations and variations Полный текст
2013
Boyacıoğlu, Hülya | Gündogdu, Vildan | Boyacıoğlu, Hayal
The development of water quality assessment strategies investigating spatial and temporal changes caused by natural and anthropogenic phenomena is an important tool in management practices. This paper used cluster analysis, water quality index method, sensitivity analysis and canonical correlation analysis to investigate priorities in pollution control activities. Data sets representing 22 surface water quality parameters were subject to analysis. Results revealed that organic pollution was serious threat for overall water quality in the region. Besides, oil and grease, lead and mercury were the critical variables violating the standard. In contrast to inorganic variables, organic and physical-inorganic chemical parameters were influenced by variations in physical conditions (discharge, temperature). This study showed that information produced based on the variations and correlations in water quality data sets can be helpful to investigate priorities in water management activities. Moreover statistical techniques and index methods are useful tools in data – information transformation process.
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