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Spatial and long-term analyses of reference and sewage-impacted sites in the SW Atlantic (38°S, 57°W) for the assessment of sensitive and tolerant polychaetes
2013
Sánchez, María A. | Jaubet, María L. | Garaffo, Griselda V. | Elías, Rodolfo
Discharges of effluent in urbanized littoral areas produce nonlinear changes in benthic organisms. Data on the composition of the benthic community are often used to obtain environmental quality classifications that serve to indicate the health of the environment. This study conducted a comparative analysis of the polychaetes associated with mussel beds and related these results to the values of environmental variables at both reference and sewage-impacted sites over a 10year period in a rocky intertidal habitat on the coast of the SW Atlantic. The results of the study showed spatial and temporal differences in the abundance and dominance of the polychaetes. The study also furnished evidence of a decrease in the environmental quality of the area. This study allowed the classification of the polychaetes into ecological groups, facilitating the calculation of environmental quality indexes.
显示更多 [+] 显示较少 [-]Environmental harm assessment of a wastewater discharge from Hammerfest LNG: A study with biomarkers in mussels (Mytilus sp.) and Atlantic cod (Gadus morhua)
2013
Beyer, Jonny | Aarab, Nadia | Tandberg, Anne Helene | Ingvarsdottir, Anna | Bamber, Shaw | Børseth, Jan Fredrik | Camus, Lionel | Velvin, Roger
Biologically treated wastewater (WW) from the Hammerfest LNG (liquefied natural gas) plant is discharged to the sea. A study using biomarkers in mussels and Atlantic cod was performed to examine whether this discharge meets a zero harmful emission requirement. Caging of mussels close to the outfall and exposure of mussels and fish to WW in the laboratory were conducted, and a suite of contaminant responsive markers was assessed in exposed animals. In mussels the markers included chemical contaminant levels, haemocyte lysosomal instability and nucleus integrity, cellular energy allocation, digestive gland and gonad histopathology and shell-opening behaviour. In fish, biliary PAH metabolites and gill histopathology biomarkers were measured. A consistent cause-effect relationship between WW treatments and markers measured in test animals was not found. The results therefore indicate that the WW emission is unlikely to represent a significant stress factor for the local marine environment under the conditions studied.
显示更多 [+] 显示较少 [-]Recent mercury contamination from artisanal gold mining on Buru Island, Indonesia – Potential future risks to environmental health and food safety
2013
Male, Yusthinus Thobias | Reichelt-Brushett, Amanda Jean | Pocock, Matt | Nanlohy, Albert
In November 2011 gold was found at Mount Botak, Buru Island, Mollucas Province, Indonesia. Since 2012 mercury has been used to extract the gold requiring large volumes of water and resulting in deposition of mercury into Wamsait River and Kayeli Bay. Total mercury in waste ponds was over 680mg/kg. In sediments at the mouth of the local river and a small feeder creek >3.00mg/kg and >7.66mg/kg respectively. River and bay sediments were proportionately higher in available mercury than elemental mercury and more strongly bound mercuric sulfide compared to that in trommel waste. This preliminary investigation raises concerns about the long term distribution and speciation of mercury. The floodplain is an important agricultural resource, and Mollucas Province is recognised nationally as the centre for Indonesian fish stocks. Challenges for management include communicating the potential future risks to the community and leaders and identifying mechanisms to reduce mercury waste.
显示更多 [+] 显示较少 [-]Three dimensional marine seismic survey has no measurable effect on species richness or abundance of a coral reef associated fish community
2013
Miller, Ian | Cripps, Edward
Underwater visual census was used to determine the effect of a three dimensional seismic survey on the shallow water coral reef slope associated fish community at Scott Reef. A census of the fish community was conducted on six locations at Scott Reef both before and after the survey. The census included small site attached demersal species belonging to the family Pomacentridae and larger roving demersal species belonging to the non-Pomacentridae families. These data were combined with a decade of historical data to assess the impact of the seismic survey. Taking into account spatial, temporal, spatio-temporal and observer variability, modelling showed no significant effect of the seismic survey on the overall abundance or species richness of Pomacentridae or non-Pomacentridae. The six most abundant species were also analysed individually. In all cases no detectable effect of the seismic survey was found on the abundance of these fish species at Scott Reef.
显示更多 [+] 显示较少 [-]Polybrominated diphenyl ethers in fat samples from White-chinned Petrels (Procellaria aequinoctialis) and Spectacled Petrels (P. conspicillata) off southern Brazil
2013
Cipro, Caio V.Z. | Colabuono, Fernanda I. | Taniguchi, Satie | Montone, Rosalinda C.
Polybrominated diphenyl ethers (PBDEs) have been gaining much visibility in environmental chemical studies due to their similarity to PCBs and growing reports of harmful effects. The fact that these contaminants have not yet undergone bans or restrictions on the global level underscores the need for data on their occurrence. In the present study, fat samples from 26 White-chinned Petrels (Procellaria aequinoctialis) and 3 Spectacled Petrels (P. conspicillata) collected dead ashore or as bycatch of longline fisheries in southern Brazil were analyzed to determine concentrations of seven congeners (IUPAC #28, 47, 99, 100, 153, 154 and 183). Concentrations of ΣPBDEs ranged from not detectable to 72.70ngg−1 (wet weight), comparatively lower than concentrations reported for seabird samples in northern hemisphere. The most detected congeners were 153, 154 and 183. This pattern is close to that previously reported for birds of the same group, but not those from the same region.
显示更多 [+] 显示较少 [-]Legacy contaminant bioaccumulation in rock crabs in Sydney Harbour during remediation of the Sydney Tar Ponds, Nova Scotia, Canada
2013
Walker, Tony R. | MacAskill, Devin | Weaver, Peter
Concentrations of PAHs, PCBs, metals and lipids in hepatopancreas of rock crabs (Cancer irroratus) were measured in Sydney Harbour (SH) for one year prior to remediation and three years of remediation of the Sydney Tar Ponds (STP), Nova Scotia. Low level concentrations of PCBs and metals were measured, although PAHs were mostly undetected. Metal concentrations showed little spatio-temporal variability, although highest concentrations of As, Cd and Cu were measured at reference stations furthest from the STP remediation site. Mercury concentrations were at least an order of magnitude lower than Canadian guidelines. Moderately elevated PCB concentrations were detected in crabs near Muggah Creek, but these were generally not higher than those measured during baseline. Despite remediation activities, current contaminant burdens measured in crabs were much lower than previously reported in other studies of crabs and lobster in industrial harbours in eastern Canada, due in part to natural recovery of SH sediments.
显示更多 [+] 显示较少 [-]Source apportionment of polycyclic aromatic hydrocarbons in surface sediment of mud areas in the East China Sea using diagnostic ratios and factor analysis
2013
Deng, Wei | Li, Xian'guo | Li, Sheng Yong | Ma, Yan Yan | Zhang, Da Hai
Polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons (AHs) have been quantified for surface sediments collected from the East China Sea (ECS). Our results showed that relatively high levels of PAHs and AHs occurred in both the inner and outer mud areas, while their concentrations at the control site were much lower. AHs for all samples were dominated by the unresolved complex mixture (UCM). Results from diagnostic ratios revealed that sedimentary PAHs were mainly originated from mixed combustion residues of biomass, coal, and petroleum. Combustion residues of petroleum and oil were responsible for the presence of high AHs concentrations. We also conducted factor analysis (FA) to further characterize the PAH and AH sources. Four factors were identified based on the loading of components and attributed to coal and wood combustion (Factor 1), traffic-related sources (Factor 2), petrogenic source (Factor 3) and natural gas combustion (Factor 4).
显示更多 [+] 显示较少 [-]Extreme irgarol tolerance in an Ulva lactuca L. population on the Swedish west coast
2013
Wendt, Ida | Arrhenius, Åsa | Backhaus, Thomas | Hilvarsson, Annelie | Holm, Christina | Langford, Katherine | Tunovic, Timur | Blanck, Hans
The herbicide irgarol 1051 is commonly used on ship hulls to prevent growth of algae, but as a component of self-eroding paints it can also spread in the surrounding waters and affect non-target organisms. The effect of irgarol on settlement and growth of zoospores from the marine macro algae Ulva lactuca from the Gullmar fjord on the Swedish west coast was investigated in the present study. The zoospores were allowed to settle and grow in the presence of irgarol, but neither settlement – nor growth inhibition was observed at concentrations of up to 2000nmoll−1. This is between 10 and 100 times higher than effect concentrations reported earlier for algae. Irgarol also induced the greening effect (4-fold increase in chlorophyll a content) in the settled zoospore/germling population, typical for photosystem II inhibitors like irgarol. This study support previous findings that irgarol constitutes a selection pressure in the marine environment.
显示更多 [+] 显示较少 [-]Sources and preservation of organic matter in soils of the wetlands in the Liaohe (Liao River) Delta, North China
2013
Lin, Tian | Ye, Siyuan | Ma, Chuanliang | Ding, Xigui | Brix, Hans | Yuan, Hongming | Chen, Yingjun | Guo, Zhigang
Total organic carbon, total nitrogen, δ13Corg, δ15N, and aliphatic and polyaromatic hydrocarbons of fifty-five soil samples collected from the coastal wetlands of the Liaohe Delta were measured, in order to determine the sources and possible preservation of organic matter (OM). The δ15N and δ13Corg values in the samples ranged from 3.0‰ to 9.4‰ and from −30.4‰ to −20.3‰, respectively, implying that the OM in the soils is predominantly derived from C3 plant. The long-chain n-alkanes had a strong odd-over-even carbon number predominance, suggesting a significant contribution from waxes of higher plants. The ubiquitous presence of unresolved complex mixture, alkylated polycylic aromatic hydrocarbons and typical biomarkers of petroleum hydrocarbons (pristane, phytane, hopanes and steranes) indicates that there is a contribution of petroleum hydrocarbons to the organic carbon pool in the wetland soils. P. australis-vegetated wetlands have strong potentials for the preservation of organic carbon in the wetlands.
显示更多 [+] 显示较少 [-]Marine debris in central California: Quantifying type and abundance of beach litter in Monterey Bay, CA
2013
Rosevelt, C. | Los Huertos, M. | Garza, C. | Nevins, H.M.
Monitoring beach litter is essential for reducing ecological threats towards humans and wildlife. In Monterey Bay, CA information on seasonal and spatial patterns is understudied. Central California’s coastal managers require reliable information on debris abundance, distribution, and type, to support policy aimed at reducing litter. We developed a survey method that allowed for trained citizen scientists to quantify the types and abundance of beach litter. Sampling occurred from July 2009–June 2010. Litter abundance ranged from 0.03 to 17.1itemsm−2. Using a mixed model approach, we found season and location have the greatest effect on litter abundance. Styrofoam, the most numerically abundant item, made up 41% of the total amount of litter. Unexpected items included fertilizer pellets. The results of this study provide a baseline on the types and abundance of litter on the central coast and have directly supported policy banning Styrofoam take out containers from local municipalities.
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