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Determination of ciprofloxacin in Jiaozhou Bay using molecularly imprinted solid-phase extraction followed by high-performance liquid chromatography with fluorescence detection
2016
Lian, Ziru | Wang, Jiangtao
A high selective pre-treatment method for the cleanup and preconcentration of ciprofloxacin in natural seawater samples was developed based on molecularly imprinted solid-phase extraction (MISPE). The ciprofloxacin imprinted polymers were synthesized and the characteristics of obtained polymers were evaluated by scanning electron microscopy, Fourier transform infrared spectroscopy and binding experiments. The imprinted materials showed high adsorption ability for ciprofloxacin and were applied as special solid-phase extraction sorbents for selective separation of ciprofloxacin. An off-line MISPE procedure was optimized and the developed MISPE method allowed direct purification and enrichment of the ciprofloxacin from the aqueous samples prior to high-performance liquid chromatography analysis. The recoveries of spiked seawater on the MISPE cartridges ranged from 75.2 to 112.4% and the relative standard deviations were less than 4.46%. Five seawater samples from Jiaozhou Bay were analyzed and ciprofloxacin was detected in two samples with the concentrations of 0.24 and 0.38μgL−1, respectively.
Mostrar más [+] Menos [-]Measures for environmental conservation in enclosed coastal seas
2016
Tomita, Akio | Nakura, Yoshio | Ishikawa, Takuya
With putting a focus on the balance among the nutrient salts such as nitrogen and phosphorus, the Ministry of the Environment (MOE) developed the Action Plan for Healthy Material Circulation in Ocean (just called the Healthy Plan). The plan aims to facilitate the healthy and smooth circulation of the nutrients with an integrated management over land and sea as a package in respective sea areas. The Healthy Plan is now in a pilot phase and is to be implemented for some selected model regions.Meanwhile, devastating tsunamis caused by the Great East Japan Earthquake on March 11th, 2011 severely damaged the natural environments in the affected regions. In the affected bays, seaweed beds and spawning grounds disappeared in a blink. MOE has launched on the recovery activities of Zostera (eelgrass) beds, using the concepts and the methods used in the “Sato-umi Creation” activity which is a purposeful environmental recovery project.
Mostrar más [+] Menos [-]Use of Amendments to Restore Ecosystem Function to Metal Mining-Impacted Sites: Tools to Evaluate Efficacy
2016
Brown, Sally L. | Chaney, Rufus L.
As in situ use of amendments for restoration of metal-contaminated mining sites becomes increasingly accepted, the expected level of ecosystem function at these sites will increase. Use of appropriate tools to measure both the level and value of that function is critical to expand use of this approach. For these sites, amendment mixtures must reduce metal availability in situ and restore ecosystem function. Combinations of mixtures, typically consisting of a material with high metal binding capacity (cyclonic ashes, municipal biosolids, or other materials rich in Fe, Al, or Mn oxides), material to adjust soil pH (sugar beet lime, cement kiln dust, dolomitic limestone), and an organic residual to provide soil structure and nutrients (composts, animal manures, municipal biosolids) have been tested in multiple lab and field trials on metal-contaminated sites. This review focuses on field tests of this approach with the goal of providing methods to quantify reduction of hazard and restoration of functional systems. Methods to evaluate success of amendments including extractions to measure changes in metal availability, microbial function and diversity, phytoavailability of metals, and earthworm and small mammal assays are discussed. In most cases, measures of metal availability and ecosystem function are related. For example, surveys of small mammals on restored sites provide information on metal availability as well as suitability of restored habitat. Additional measures of ecosystem function including soil fertility, physical properties, and diversity of habitat are described. Finally, measures of the value of this approach for restoring ecosystems are detailed.
Mostrar más [+] Menos [-]Sources and sinks of plastic debris in estuaries: A conceptual model integrating biological, physical and chemical distribution mechanisms
2016
Vermeiren, Peter | Muñoz, Cynthia C. | Ikejima, Kou
Micro- and macroplastic accumulation threatens estuaries worldwide because of the often dense human populations, diverse plastic inputs and high potential for plastic degradation and storage in these ecosystems. Nonetheless, our understanding of plastic sources and sinks remains limited. We designed conceptual models of the local and estuary-wide transport of plastics. We identify processes affecting the position of plastics in the water column; processes related to the mixing of fresh and salt water; and processes resulting from the influences of wind, topography, and organism–plastic interactions. The models identify gaps in the spatial context of plastic–organisms interactions, the chemical behavior of plastics in estuaries, effects of wind on plastic suspension–deposition cycles, and the relative importance of processes affecting the position in the water column. When interpreted in the context of current understanding, sinks with high management potential can be identified. However, source–sink patterns vary among estuary types and with local scale processes.
Mostrar más [+] Menos [-]Is meiofauna community structure in Artificial Substrate Units a good tool to assess anthropogenic impact in estuaries?
2016
Costa, Ana Bolena Harten Pinto | Valença, Ana Paula Maria Cavalcanti | Santos, Paulo Jorge Parreira dos
The applicability of estuarine meiofauna and harpacticoid copepods' communities in an artificial substrate unit (ASU) was assessed and compared to natural substrates (sediment and pneumatophores) as a tool to discern estuaries under different types of anthropogenic impacts. The ASU's replicates demonstrated a low variation of density among replicates when considering the total meiofauna and copepod species, which was reflected by a great similarity within the samples. In relation to the most abundant groups found, the ASU samples properly represented the natural substrates, even though nematodes were poor colonizers. That the ASU only showed significant differences between areas suggested that standard substrates could more efficiently detect the differences between communities and pointed toward the applicability of ASUs meiobenthic communities as useful tools for impact studies.
Mostrar más [+] Menos [-]Risk assessment for marine spills along European coastlines
2016
Fernández-Macho, Javier
A marine-spill risk index is proposed to measure and compare the relative vulnerability of coastal regions to marine spills in European waters. It is applied to 301 spills in European waters between 1970 and 2014 for 429 Eurostat territorial units and 156 regions in Europe's coasts. The results show a high heterogeneity among European coastal regions with areas, predominantly on the Atlantic coast, with high marine-spill risks. In particular, UK coasts are markedly affected as there are only five non-British coastal territories within the first 25 territorial units most at risk from marine spills. Across countries, European Atlantic countries face highest risks versus coastal countries on other European waters that are relatively safer. The index also shows a tendency of sea currents to have positive dispersal effects leading to smaller risks rather than otherwise. The index may help to design protection policies and reduce the vulnerability of sensitive resources.
Mostrar más [+] Menos [-]Effects of short-term hypoxia and seawater acidification on hemocyte responses of the mussel Mytilus coruscus
2016
Sui, Yanming | Kong, Hui | Shang, Yueyong | Huang, Xizhi | Wu, FangLi | Hu, Menghong | Lin, Daohui | Lu, Weiqun | Wang, Youji
Hypoxia often intensifies with rising dissolved CO2, but the concurrent effects of hypoxia and acidification on bivalves are largely unknown. In this study, immune responses of hemocytes in the mussel Mytilus coruscus were examined under six combinations of pH (7.3, 7.7 and 8.1) and dissolved oxygen (DO) concentrations (2mgL−1, 6mgL−1) for 72h. Generally, total hemocyte account, phagocytosis, esterase and lysosomal content were reduced under low DO and pH conditions, whereas hemocyte mortality and reactive oxygen species production increased under low DO and pH. Both hypoxia and low pH have negative effects on mussels, but the effects of pH are not as strong as DO. Moreover, significant interactions between DO and pH occurred. However, acidification generally doesn't aggravate the effects induced by hypoxia. Acidification and hypoxia may increase disease risk and impact the aquaculture of this species.
Mostrar más [+] Menos [-]A review of crustacean sensitivity to high amplitude underwater noise: Data needs for effective risk assessment in relation to UK commercial species
2016
Edmonds, Nathan J. | Firmin, Christopher J. | Goldsmith, D. (Denise) | Faulkner, Rebecca C. | Wood, Daniel T.
High amplitude anthropogenic noise is associated with adverse impacts among a variety of organisms but detailed species-specific knowledge is lacking in relation to effects upon crustaceans. Brown crab (Cancer pagurus), European lobster (Homarus gammarus) and Norway lobster (Nephrops norvegicus) together represent the most valuable commercial fishery in the UK (Defra, 2014). Critical evaluation of literature reveals physiological sensitivity to underwater noise among N. norvegicus and closely related crustacean species, including juvenile stages. Current evidence supports physiological sensitivity to local, particle motion effects of sound production in particular. Derivation of correlative relationships between the introduction of high amplitude impulsive noise and crustacean distribution/abundance is hindered by the coarse resolution of available data at the present time. Future priorities for research are identified and argument for enhanced monitoring under current legislative frameworks outlined.
Mostrar más [+] Menos [-]Metagenomic analysis between free-living and cultured Epinephelus fuscoguttatus under different environmental conditions in Indonesian waters
2016
Hennersdorf, Philipp | Mrotzek, Grit | Abdul-Aziz, Muslihudeen A. | Saluz, Hans Peter
In this study, we analyzed and compared feces of free-living and cultivated fish species, Epinephelus fuscoguttatus under different environmental conditions in Indonesian waters. Metagenome analysis was performed using Illumina MiSeq sequencing of the whole metagenomic DNA isolated from fish feces samples. The analysis covered both prokaryotic and eukaryotic DNA. Feces samples from mariculture fish revealed a highly stable distribution of several orders of bacteria when compared to samples from free-living fish, which were highly diverse and dominated by Vibrionales, Pseudomonales, Rhizobiales and non-classifiable Alphaproteobacteria. The eukaryotic content of the samples was dominated by residues of the host and nine additional fish species that formed a portion of the diet. Investigations on functional annotations for predominant bacterial taxa, using Gene Ontology enrichment, revealed a number of functions related to DNA metabolic processes, especially DNA repair, as well as antibiotic response in the free-living fish species.
Mostrar más [+] Menos [-]Sustainability and the Spanish port system. Analysis of the relationship between economic and environmental indicators
2016
Laxe, Fernando González | Bermúdez, Federico Martín | Palmero, Federico Martín | Novo Corti, Isabel
Research into the methodological development of alternative systems of sustainability measures is recent. In understanding sustainable development in a multi-dimensional sense, one of the most significant advances was the construction of Synthetic Indexes, applicable to different spatial spheres or to organisations, businesses, institutions, etc.The Spanish port system of general interest comprises 46 ports integrated in 28 Port Authorities, which in 2014 moved 482,000,000t of goods and more than 28 million passengers. This gives an idea of its importance for the Spanish economy.Using a derivation of the procedure used to calculate the Port Sustainability Synthetic Index, in this research the analysis of the relationship that exists between the findings obtained for the economic and environmental dimensions is used. This enables the existence of links between ports and economic and environmental indicators for a sample of 16 Port Authorities of Spain to be verified.
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