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Monitoring trace elements in Antarctic penguin chicks from South Shetland Islands, Antarctica 全文
2013
Jerez, Silvia | Motas, Miguel | Benzal, Jesús | Díaz, Julia | Barbosa, Andrés
The concentration of human activities in the near-shore ecosystems from the northern Antarctic Peninsula area can cause an increasing bioavailability of pollutants for the vulnerable Antarctic biota. Penguin chicks can reflect this potential impact in the rookeries during the breeding season. They also can reflect biomagnification phenomena since they are on the top of the Antarctic food chain. The concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and Pb were measured by ICP-MS in samples of liver, kidney, muscle, bone, feather and stomach content of gentoo, chinstrap and Adélie penguin chicks (n=15 individuals) collected opportunistically in the Islands of King George and Deception (South Shetland Islands, Antarctica). The detected levels of some trace elements were not as low as it could be expected in the isolated Antarctic region. Penguin chicks can be useful indicators of trace elements abundance in the study areas.Carcasses of Antarctic penguin chicks were used to evaluate the bioavailability of trace elements in the Islands of King George and Deception.
显示更多 [+] 显示较少 [-]Thorium(IV) removal from aqueous medium by citric acid treated mangrove endophytic fungus Fusarium sp. #ZZF51 全文
2013
Yang, S.K. | Tan, N. | Yan, X.M. | Chen, F. | Long, W. | Lin, Y.C.
Thorium(IV) biosorption is investigated by citric acid treated mangrove endophytic fungus Fussarium sp. #ZZF51 (CA-ZZF51) from South China Sea. The biosorption process was optimized at pH 4.5, equilibrium time 90min, initial thorium(IV) concentration 50mgL−1 and adsorbent dose 0.6gL−1 with 90.87% of removal efficiency and 75.47mgg−1 of adsorption capacity, which is obviously greater than that (11.35mgg−1) of the untreated fungus Fussarium sp. #ZZF51 for thorium(IV) biosorption under the condition of optimization. The experimental data are analyzed by using isotherm and kinetic models. Kinetic data follow the pseudo-second-order model and equilibrium data agree very well with the Langmuir model. In addition, FTIR analysis indicates that hydroxyl, amino, and carbonyl groups act as the important roles in the adsorption process.
显示更多 [+] 显示较少 [-]Methylmercury in fish from the South China Sea: Geographical distribution and biomagnification 全文
2013
Zhu, Aijia | Zhang, Wei | Xu, Zhanzhou | Huang, Liangmin | Wang, Wen-Xiong
We conducted a large-scale investigation of methylmercury (MeHg) in a total of 628 marine wild fish covering 46 different species collected from the South China Sea between 2008 and 2009. Biological and ecological characteristics such as size (length and wet weight), feeding habit, habitat, and stable isotope (δ15N) were examined to explain MeHg bioaccumulation in marine fish and their geographical distribution. MeHg levels in the muscle tissues of the 628 individuals ranged from 0.010 to 1.811μg/gdrywt. Log10MeHg concentration was significantly related to their length and wet weight. Feeding habit and habitat were the primary factors influencing MeHg bioaccumulation. Demersal fish were more likely to be contaminated with MeHg than the epipelagic and mesopelagic varieties. Linear relationships were obtained between Log10(MeHg) and δ15N only for one location, indicating that biomagnification was site-specific. Results from this study suggest that dietary preference and trophic structure were the main factors affecting MeHg bioaccumulation in marine fish from the South China Sea.
显示更多 [+] 显示较少 [-]Resistance of Lophelia pertusa to coverage by sediment and petroleum drill cuttings 全文
2013
Allers, Elke | Abed, Raeid M.M. | Wehrmann, Laura M. | Wang, Tao | Larsson, Ann I. | Purser, Autun | De Beer, Dirk
In laboratory experiments, the cold-water coral Lophelia pertusa was exposed to settling particles. The effects of reef sediment, petroleum drill cuttings and a mix of both, on the development of anoxia at the coral surface were studied using O2, pH and H2S microsensors and by assessing coral polyp mortality. Due to the branching morphology of L. pertusa and the release of coral mucus, accumulation rates of settling material on coral branches were low. Microsensors detected H2S production in only a few samples, and sulfate reduction rates of natural reef sediment slurries were low (<0.3nmolScm−3d−1). While the exposure to sediment clearly reduced the coral’s accessibility to oxygen, L. pertusa tolerated both partial low-oxygen and anoxic conditions without any visible detrimental short-term effect, such as tissue damage or death. However, complete burial of coral branches for >24h in reef sediment resulted in suffocation.
显示更多 [+] 显示较少 [-]Ocean in peril: Reforming the management of global ocean living resources in areas beyond national jurisdiction 全文
2013
Gjerde, Kristina M. | Currie, Duncan | Wowk, Kateryna | Sack, Karen
This article presents the outcome of research aimed at assisting governments in meeting their commitments and legal obligations for sustainable fisheries, based on increasing evidence that global fisheries are in crisis. The article assesses the effectiveness of the existing legal and institutional framework for high seas living resources. It focuses on: (1) the role of regional fisheries management organizations (RFMOs); (2) tools for compliance and enforcement to stem illegal fishing; and (3) mechanisms for habitat protection. The article further highlights a variety of options for addressing key weaknesses and gaps in current ocean governance, including United Nations General Assembly (UNGA) resolutions, reforms at the regional level, as well as a possible new legal instrument, with a view to informing international discussions on ways to ensure the sustainable use of high seas resources without compromising the health of the marine environment.
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 全文
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 [-]Optimization of nutrient component for diesel oil degradation by Acinetobacter beijerinckii ZRS 全文
2013
Huang, Lei | Xie, Jing | Lv, Bo-yi | Shi, Xiao-feng | Li, G. Q. | Liang, Feng-lai | Lian, Jing-yan
A new bacterial strain that is capable of using diesel as the sole carbon source was isolated from the petroleum-contaminated soil of Xinjiang oil field, Northwest China. This bacterium was identified on the basis of its morphological and physiological characteristics and 16S rRNA gene sequence analysis, and it showed the greatest similarity with Acinetobacter beijerinckii 302-PWB-OH1 (99.86%). In order to enhance degradation efficiency, single-factor experiments and response surface methodology (RSM) were employed to optimize the nutrients used in artificial seawater. The results of this study revealed that 2.05gL−1 (NH4)2SO4, 1.46gL−1 Na2HPO4, and 14mgL−1 yeast extract in artificial seawater resulted in increasing the diesel degradation rate of the bacterial strain from 20.87% to 80.40% within 7days. The actual experimental results were in agreement with the prediction.
显示更多 [+] 显示较少 [-]Extreme irgarol tolerance in an Ulva lactuca L. population on the Swedish west coast 全文
2013
Wendt, Ida | Arrhenius, Åsa | Backhaus, Thomas | Hilvarsson, Annelie | Holm, Christina | Langford, Katherine | Tunovic, Timur | Blanck, Hans
Extreme irgarol tolerance in an Ulva lactuca L. population on the Swedish west coast 全文
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 [-]Effects of Five Antifouling Biocides on Settlement and Growth of Zoospores from the Marine Macroalga Ulva lactuca L 全文
2013
Wendt, Ida | Arrhenius, Åsa | Backhaus, Thomas | Hilvarsson, Annelie | Holm, Christina | Langford, Katherine | Tunovic, Timur | Blanck, Hans
Antifouling biocides are found in the marine ecosystem were they can affect non-target organisms. In this study the effects of five antifouling biocides on the settlement and growth of Ulva lactuca zoospores were investigated. The biocides investigated were copper (Cu²⁺), 4,5-dichloro-2-n-octyl-3(2H)-isothiazolone (DCOIT), triphenylborane pyridine (TPBP), tolylfluanid and medetomidine. Full concentration–response curves where determined for each compound. EC₅₀ values were determined for copper, DCOIT, TPBP and tolylfluanid, all of which inhibited settlement and growth in a concentration dependent manner with the following toxicity ranking; tolylfluanid (EC₅₀ 80 nmol L⁻¹) ~ DCOIT (EC₅₀ 83 nmol L⁻¹) > TPBP (EC₅₀ 400 nmol L⁻¹) > Cu²⁺ (EC₅₀ 2,000 nmol L⁻¹). Medetomidine inhibited settlement and growth only at the extreme concentration of 100,000 nmol L⁻¹ (93 % effect). The low toxicity is possibly a consequence of a lack of receptors that medetomidine can bind to in the U. lactuca zoospores.
显示更多 [+] 显示较少 [-]On the Efficacy and Ecotoxicity of Antifouling Biocides Lethal and Sublethal Effects on Target and Non-target Organisms 全文
2013
Wendt, Ida
From an environmental perspective, there is a need to reduce the amount of biocides from antifouling paints in the marine ecosystem as these biocides can exert a negative effect on the marine life. One way to do this is to optimize the use of biocides in antifouling paints, and thereby avoid unnecessary overdosing. This thesis has been produced within the research program Marine Paint which has the overall aim to produce an antifouling paint with a lower environmental impact than the paints existing on the market today. The aim of the studies presented in this thesis has been to evaluate the efficacy and ecotoxicity of eight antifouling biocides to both target and non-target organisms. The biocides investigated were: medetomidine, triphenylborane pyridine (TPBP), tolylfluanid, copper, irgarol, zinc pyrithione, copper pyrithione and 4,5-dichloro-2-n-octyl 3(2H)-isothiazolone (DCOIT). The target organisms investigated were the macroalga Ulva lactuca and periphyton (i.e. microbial communities). It is important to keep in mind that all target organisms that antifouling biocides are meant to affect, are also non-target organisms when they grow on natural substrates in the marine ecosystem. Therefore, effects on target organisms are not only of interest for efficacy evaluations, but also for ecotoxicological assessments of the biocides. Both the efficacy and ecotoxicity of the eight biocides has been evaluated for the target organisms in settlement assays in which the organisms were allowed to settle and grow in the presence of the biocides. Full concentration-response curves from 0 to 100 % effect were produced to enable future mixture predictions. Such mixture predictions can be used for paint optimization, but also in environmental applications such as hazard assessments. Copper pyrithione was the biocide that most efficiently prevented growth of both Ulva lactuca and periphyton communities, and for Ulva lactuca is was also the biocide with the highest ecotoxicity. Due to different shapes of the concentration-response curves, the toxicity ranking was not consistent at all effect levels (from EC10 to EC98), and irgarol was found to be more toxic to periphyton at lower concentrations than copper pyrithione. In order to extend the ecotoxicological evaluations of the biocides beyond target organisms, effects on the non-target organism Acartia tonsa was investigated. Acartia tonsa is one of the most commonly occurring pelagic calanoid copepods in coastal waters world-wide. Effects on mortality and egg production were studied for three of the eight biocides, namely DCOIT, TPBP and medetomidine. It was shown that neither DCOIT nor medetomidine affected the egg production specifically, but inhibition of egg production occurred at the same concentration as mortality. TPBP was on the other hand shown to affect the egg production at concentrations lower than lethal concentrations. Antifouling biocides present in the marine environment can exert selection pressure on marine life and through the process of natural selection induce tolerance development. An extreme tolerance to the antifouling biocide irgarol in a population of Ulva lactuca from the mouth of the Gullmar fjord has been described. This indicates that the use of antifouling paints has made its imprint on the marine ecosystem. The results from this thesis have deepened the understanding of the biological effects of antifouling biocides. The well-defined concentration-response curves gives information on both efficacy and ecotoxicity, and the information can be used in a number of applications where either biocidal efficacy or ecotoxicity is of interest, such as hazard assessments and in the design of antifouling paints.
显示更多 [+] 显示较少 [-]Acid-volatile sulfide and simultaneously extracted metals in surface sediments of the southwestern coastal Laizhou Bay, Bohai Sea: Concentrations, spatial distributions and the indication of heavy metal pollution status 全文
2013
Zhuang, Wen | Gao, Xuelu
Surface sediments were collected from the coastal waters of southwestern Laizhou Bay and the rivers it connects with during summer and autumn 2012. The acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) were measured to assess the sediment quality. The results showed that not all sediments with [SEM]–[AVS]>0 were capable of causing toxicity because the organic carbon is also an important metal-binding phase in sediments. Suppose the sediments had not been disturbed and the criteria of US Environmental Protection Agency had been followed, heavy metals in this area had no adverse biological effects in both seasons except for few riverine samples. The major ingredient of SEM was Zn, whereas the contribution of Cd – the most toxic metal studied – to SEM was <1%. The distributions of AVS and SEM in riverine sediments were more easily affected by anthropogenic activity compared with those in marine sediments.
显示更多 [+] 显示较少 [-]Polybrominated diphenyl ethers do not affect metamorphosis but alter the proteome of the invasive slipper limpet Crepidula onyx 全文
2013
Mukerji, Joy | Po, Beverly H.K. | Chiu, Jill M.Y. | Wu, Rudolf S.S. | Qian, Pei-Yuan | Thiyagarajan, Vengatesen
Man-made polybrominated diphenyl ethers (PBDEs) used as flame retardants in various consumer products may be harmful to marine organisms. Larvae of some marine invertebrates, especially invasive species, can develop resistance to PBDEs through altered protein expression patterns or proteome plasticity. This is the first report of a proteomics approach to study BDE-47 induced molecular changes in the invasive limpet Crepidula onyx. Larvae of C. onyx were cultured for 5days (hatching to metamorphosis) in the presence of BDE-47 (1μgL−1). Using a 2-DE proteomics approach with triple quadrupole and high-resolution TOF-MS, we showed that BDE-47 altered the proteome structure but not the growth or metamorphosis of C. onyx larvae. We found eight significant differentially expressed proteins in response to BDE-47, deemed the protein expression signature, consisting of cytoskeletal, stress tolerance, metabolism and energy production related proteins. Our data suggest C. onyx larvae have adequate proteome plasticity to tolerate BDE-47 toxicity.
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