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Survival and movements of Magellanic penguins rehabilitated from oil fouling along the coast of South America, 2000–2010
2012
Ruoppolo, Valeria | Vanstreels, Ralph Eric Thijl | Woehler, E. J. (Eric J.) | Heredia, Sergio Andres Rodríguez | Adornes, Andréa Corrado | Silva-Filho, Rodolfo Pinho da | Matus, Ricardo | Poleschi, Carla | Griot, Karen | Kolesnikovas, Cristiane K Miyaji | Serafini, Patrícia
Oil pollution is a significant conservation concern. We examined data from six institutions along the coast of South America: Emergency Relief Team of the International Fund for Animal Welfare, Fundación Mundo Marino, Centro de Recuperação de Animais Marinhos, Natura Patagonia, Associação R3 Animal, and Mar del Plata Aquarium and data from resightings in Argentina, Brazil, Chile and Falkland/Malvinas Islands. From 2000 to 2010, 2183 oiled Magellanic penguins were rehabilitated as part of the routine activities of these institutions or during emergency responses to eight oil spills in which they were involved; all rehabilitated penguins were flipper banded and released. Since their release, 41 penguins were resighted until 31 December 2011. The results demonstrate that, when combined with other prevention strategies, the rehabilitation of Magellanic penguins is a strategy that contributes to the mitigation of adverse effects of oil spills and chronic pollution to the species.
Mostrar más [+] Menos [-]Toxic metal (Pb, Cd and Hg) levels in the nearshore surface sediments from the European and Anotolian Shores of Bosphorus, Turkey
2012
Balkıs, Nuray | Aktan, Yelda | Balkıs, Neslihan
In this study, some toxic metal such as Pb, Cd and Hg analyzes have been done in the nearshore surface sediments. Sediment samples have been collected from five parts from the European and Anotolian Shores of the Bosphorus during 2003–2004. Total Pb, Cd and Hg contents vary between <0.01μgg⁻¹ and 238μgg⁻¹; <0.01μgg⁻¹ and 0.92μgg⁻¹; 0.001μgg⁻¹ and 0.45μgg⁻¹, respectively. Contamination Factor (CF) values of Pb and Cd range between 1 and 3 whilst CF values of Hg are lower than 1 in all the stations. It means that there are no Hg metal enrichment by natural or anthropogenic inputs contrary to moderately contamination for Pb and Cd metals throughout the Bosphorus sediments.
Mostrar más [+] Menos [-]Use of aliphatic hydrocarbons to infer terrestrial organic matter in coastal marine sediments off China
2012
Liu, Liang-Ying | Wang, Ji-Zhong | Guan, Yu-Feng | Zeng, E. Y. (Eddy Y.)
Sediment samples from the marine systems along the coast of China, covering Yellow Sea, inner shelf of the East China Sea (ECS) and the South China Sea (SCS), were analyzed for n-alkanes and organic carbon. The concentrations of Σn–C₁₅–₃₅ were 120–1680ngg⁻¹ dry weight with an average of 560ngg⁻¹. Short-chain n-alkanes (<C₂₁) in Yellow Sea and the SCS were derived from mixed bacteria and planktonic sources, while those in the ECS inner shelf were mainly of planktonic sources. Long-chain n-alkanes (>C₂₁) were mainly derived from terrestrial higher plants. Organic carbon deposited into Yellow Sea and Southeast Hainan within the SCS was mainly of terrestrial (13–110%; mean: 58%) and marine (48–110%; mean: 86%) sources, respectively. On the other hand, organic carbon accumulated in the SCS adjacent to the Pearl River Estuary was derived from both terrestrial and marine sources.
Mostrar más [+] Menos [-]Comprehensive assessment of heavy metal contamination in sediment of the Pearl River Estuary and adjacent shelf
2012
Yang, Yongqiang | Chen, Fanrong | Zhang, Ling | Liu, Jinsong | Wu, Shijun | Kang, Mingliang
Total metal concentrations (Cr, Ni, Cu, Zn, and Pb), acid volatile sulfide and simultaneously extracted metals (AVS–SEM), and heavy metal fractionation were used to assess the heavy metals contamination status and ecological risk in the sediments of the Pearl River Estuary (PRE) and adjacent shelf. Elevated concentrations at estuarine sites and lower concentrations at adjacent shelf sites are observed, especially for Cu and Zn. Within the PRE, the concentration of heavy metals in the western shore was mostly higher than that in the middle shore. The metals from anthropogenic sources mainly occur in the labile fraction and may be taken up by organisms as the environmental parameters change. A combination of total metal concentrations, metal contamination index and sequential extraction analysis is necessary to get the comprehensive information on the baseline, anthropogenic discharge and bioavailability of heavy metals.
Mostrar más [+] Menos [-]Northern fulmars as biological monitors of trends of plastic pollution in the eastern North Pacific
2012
Avery-Gomm, Stephanie | O’Hara, Patrick D. | Kleine, Lydia | Bowes, Victoria | Wilson, Laurie K. | Barry, Karen L.
Marine plastic debris is a global issue, which highlights the need for internationally standardized methods of monitoring plastic pollution. The stomach contents of beached northern fulmar (Fulmarus glacialis) have proven a cost-effective biomonitor in Europe. However, recent information on northern fulmar plastic ingestion is lacking in the North Pacific. We quantified the stomach contents of 67 fulmars from beaches in the eastern North Pacific in 2009–2010 and found that 92.5% of fulmars had ingested an average of 36.8 pieces, or 0.385g of plastic. Plastic ingestion in these fulmars is among the highest recorded globally. Compared to earlier studies in the North Pacific, our findings indicate an increase in plastic ingestion over the past 40years. This study substantiates the use of northern fulmar as biomonitors of plastic pollution in the North Pacific and suggests that the high levels of plastic pollution in this region warrant further monitoring.
Mostrar más [+] Menos [-]Enrichment of rare earth elements as environmental tracers of contamination by acid mine drainage in salt marshes: A new perspective
2012
Delgado, J. (Joaquín) | Pérez López, Rafael | Galván, Laura | Nieto, José Miguel | Boski, Tomasz
Rare earth elements (REE) were analyzed in surface sediments from the Guadiana Estuary (SW Iberian Pyrite Belt). NASC (North American Shale Composite) normalized REE patterns show clearly convex curvatures in middle-REE (MREE) with respect to light- and heavy-REE, indicating acid-mixing processes between fluvial waters affected by acid mine drainage (AMD) and seawater. However, REE distributions in the mouth (closer to the coastal area) show slightly LREE-enriched and flat patterns, indicating saline-mixing processes typical of the coastal zone. NASC-normalized ratios (La/Gd and La/Yb) do not discriminate between both mixing processes in the estuary. Instead, a new parameter (EMREE) has been applied to measure the curvature in the MREE segment. The values of EMREE>0 are indicative of acid signatures and their spatial distribution reveal the existence of two decantation zones from flocculation processes related to drought periods and flood events. Studying REE fractionation through the EMREE may serve as a good proxy for AMD-pollution in estuarine environments in relation to the traditional methods.
Mostrar más [+] Menos [-]Macrobenthic community for assessment of estuarine health in tropical areas (Northeast, Brazil): Review of macrofauna classification in ecological groups and application of AZTI Marine Biotic Index
2012
Valença, Ana Paula M.C. | Santos, Paulo J.P.
The aim of the present study was to investigate the ecological quality of tropical estuaries on the northeastern coast of Brazil using the AMBI. Macrofauna classification based on ecological groups was reviewed using the Indicator Value (IndVal) coefficient. The results indicate that the ecosystems exhibit some level of disturbance. Most sites are situated between slightly-moderately disturbed boundaries due to the higher proportion of Nematoda (assigned here as Ecological Group I) and of Oligochaeta and Tubificidae (both classified as Ecological Group V). The AMBI proved efficient in evaluating environmental status, although the applicability of this index requires adjustments regarding some species in ecological groups. The present study also highlights the merits of the IndVal method for examining the assignments of species/taxa to an ecological group and demonstrates the validity of this coefficient is an assessment tool. Moreover, the complementary use of different methods is recommended for the assessment of ecosystem quality.
Mostrar más [+] Menos [-]A marine secondary producer respires and feeds more in a high CO₂ ocean
2012
Li, Wei | Gao, Kunshan
Climate change mediates marine chemical and physical environments and therefore influences marine organisms. While increasing atmospheric CO₂ level and associated ocean acidification has been predicted to stimulate marine primary productivity and may affect community structure, the processes that impact food chain and biological CO₂ pump are less documented. We hypothesized that copepods, as the secondary marine producer, may respond to future changes in seawater carbonate chemistry associated with ocean acidification due to increasing atmospheric CO₂ concentration. Here, we show that the copepod, Centropages tenuiremis, was able to perceive the chemical changes in seawater induced under elevated CO₂ concentration (>1700μatm, pH<7.60) with avoidance strategy. The copepod’s respiration increased at the elevated CO₂ (1000μatm), associated acidity (pH 7.83) and its feeding rates also increased correspondingly, except for the initial acclimating period, when it fed less. Our results imply that marine secondary producers increase their respiration and feeding rate in response to ocean acidification to balance the energy cost against increased acidity and CO₂ concentration.
Mostrar más [+] Menos [-]Distribution and sources of organochlorine pesticides in sediments of the coastal East China Sea
2012
Lin, Tian | Hu, Limin | Shi, Xuefa | Li, Yuanyuan | Guo, Zhigang | Zhang, Gan
Forty-two surface sediment samples collected from the southern coastal East China Sea (ECS) were analyzed for organochlorine pesticides (OCPs). The results showed high concentrations of DDTs and parent DDT fractions in the nearshore area, suggesting that there is still a fresh input of these species from non-point sources, probably due to the recent usage of relevant products. However, for HCHs, the high concentrations with elevated β-HCH fraction were focused at the local major river estuaries, indicating that soils-released HCH input was mainly from the major river runoffs. The distribution and composition of OCPs in the coastal ECS could be more prominently controlled by the direct regional inputs rather than the general natural sorption process on particulate organic carbon. DDTs and chlordane are more important for their potential ecotoxicological risk on neighboring benthic community in the nearshore region and the local major river estuaries.
Mostrar más [+] Menos [-]Reproductive characteristics and steroid levels in the scleractinian coral Oculina patagonica inhabiting contaminated sites along the Israeli Mediterranean coast
2012
Armoza-Zvuloni, Rachel | Kramarsky-Winter, Esti | Rosenfeld, Hanna | Shore, Laurence S. | Segal, Roee | Sharon, Daniel | Loya, Yossi
In this study we compared reproductive characteristics and steroid hormone levels in the non-indigenous scleractinian coral, Oculina patagonica, inhabiting contaminated vs. uncontaminated reference sites along the Israeli Mediterranean coast. Our results indicate significantly higher steroid levels in both seawater and coral tissue samples from contaminated sites as compared to reference sites, suggesting that corals tend to accumulate steroids from the surrounding waters. Despite their higher steroid levels, corals from the contaminated sites showed reproductive potential comparable to those of the reference sites. Interestingly, a clear distinction could be seen between corals exposed to pollution for long vs. short durations, with the latter showing a failure to complete gametogenesis. This suggests that reproduction in O. patagonica is susceptible to acute rather than chronic stress. The involvement of adjustment/adaptation processes may explain this species tolerance, and may reflect the ability of O. patagonica to successfully invade new areas in the Mediterranean Sea.
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