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Occurrence and distribution of antifouling biocide Irgarol-1051 in coastal waters of Peninsular Malaysia 全文
2013
Ali, Hassan Rashid | Arifin, Marinah Mohd | Sheikh, Mohammed Ali | Mohamed Shazili, Noor Azhar | Zainudin Bachok,
Emerging booster biocides contamination raises particular attention in the marine ecosystem health. This study provides the baseline data on the occurrence of Irgarol-1051 (2-methylthio-4-tert-butylamino-6-cyclopropylamiono-s-triazine) in the selected coastal water around Malaysia. The maximum detected concentration of Irgarol was 2021ng/L at Klang West, commercial and cargo port. Coral reef Islands (Redang and Bidong) were relatively less contaminated compared to other coastal areas. The temporal variation revealed that only 1% of 28 stations sampled on November, 2011 was above the environmental risk limit of 24ng/L as suggested by Dutch Authorities, while in January and April, 2012; 46% and 92% of the stations were above the limit respectively. The present findings demonstrate the wide detection of novel antifouling materials Irgarol-1051 which advocates the need for proper monitoring and conservation strategies for the coastal resources.
显示更多 [+] 显示较少 [-]Mercury profiles in surface sediments from ten bays along the coast of Southern China 全文
2013
Xu, Weihai | Yan, Wen | Huang, Weixia | Chen, Zhong | Wang, Shuhong | Miao, Li | Zhong, Lifeng | Chen, Han
Spatial and temporal variations of mercury (Hg) were investigated from ten representative bays along the coast of Southern China. The total Hg (THg) in surface sediments varied widely with concentrations from 25 to 264ng/g. As a whole, Hg pollution in several bays occupied by busy sea traffic and industrial activities, such as Shantou (ST) Bay and Dapeng (DP) Bay were remarkably more serious than others, which reflected the direct effects of anthropogenic activities around the coastal areas. Hg variations in sediment cores clearly display upcore rising trend which obviously correlates with the trend of economic development and urbanization in the last five decades. No significant correlations were found between Hg and organic matter and particle size, suggesting that the distribution of Hg is not fully controlled by these variables.
显示更多 [+] 显示较少 [-]Corals from the Persian/Arabian Gulf as models for thermotolerant reef-builders: Prevalence of clade C3 Symbiodinium, host fluorescence and ex situ temperature tolerance 全文
2013
Hume, B. | D’Angelo, C. | Burt, J. | Baker, A.C. | Riegl, B. | Wiedenmann, J.
Corals in the Arabian/Persian Gulf endure summer temperatures of up to 36°C, making them ideal subjects to study the mechanisms underlying thermal tolerance. Unexpectedly, we found the “generalist” Symbiodinium clade C3 to be the prevalent symbiont among seven coral species from Abu Dhabi (UAE) waters. Moreover, C3 represented the only dominant symbiont type in Porites spp. from this region. The “thermotolerant” symbionts D1a and C15 were not encountered, indicating that the association with these symbionts cannot be the sole reason for the heat tolerance of Gulf corals. The association of Porites lobata with specific symbiont types (C3 vs. C15) in samples from habitats with very different temperature regimes (Abu Dhabi vs. Fiji) remained unaffected by laboratory culture. During temperature stress experiments specimens from both locations strongly downregulated green fluorescent protein (GFP)-like pigments. However, the Abu Dhabi samples were less prone to bleaching and showed lower mortality.
显示更多 [+] 显示较少 [-]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 [-]The effects of mercury on the dynamics of the peracarida community in a temperate coastal lagoon (Ria de Aveiro, Portugal) 全文
2013
Cardoso, P.G. | D’Ambrosio, M. | Marques, S.C. | Azeiteiro, U.M. | Coelho, J.P. | Pereira, E.
The effects of mercury on the dynamics of the peracarida community in a temperate coastal lagoon (Ria de Aveiro, Portugal) 全文
2013
Cardoso, P.G. | D’Ambrosio, M. | Marques, S.C. | Azeiteiro, U.M. | Coelho, J.P. | Pereira, E.
This study focuses on the impact of mercury on the dynamics and bioaccumulation patterns of suprabenthic peracarida community along a mercury gradient. Suprabenthic peracarida was negatively affected in terms of biomass, diversity and productivity. Mysids including Mesopodopsis slabberi dominated the community, presenting a regular distribution along the Hg gradient, so are considered tolerant species to mercury. Then, isopods, the second most abundant group, dominated in the most contaminated areas being considered also a tolerant group. Contrarily, amphipods were negatively correlated with higher Hg concentrations, dominating in the intermediate areas, thus are considered more sensitive species. In addition, isopods and amphipods were the taxa with higher mercury body burden, followed by mysids. This paper highlights the importance of suprabenthic peracarida as a vehicle of mercury transference through the estuarine trophic web since it is a main link between benthic and pelagic levels and an essential food resource for numerous fish species.
显示更多 [+] 显示较少 [-]The effects of mercury on the dynamics of the peracarida community in a temperate coastal lagoon (Ria de Aveiro, Portugal) 全文
1000 | 2013
Cardoso, P G | D’Ambrosio, M | Marques, S C | Azeiteiro, U M | Coelho, J P | Pereira, E
This study focuses on the impact of mercury on the dynamics and bioaccumulation patterns of suprabenthic peracarida community along a mercury gradient. Suprabenthic peracarida was negatively affected in terms of biomass, diversity and productivity. Mysids including Mesopodopsis slabberi dominated the community, presenting a regular distribution along the Hg gradient, so are considered tolerant species to mercury. Then, isopods, the second most abundant group, dominated in the most contaminated areas being considered also a tolerant group. Contrarily, amphipods were negatively correlated with higher Hg concentrations, dominating in the intermediate areas, thus are considered more sensitive species. In addition, isopods and amphipods were the taxa with higher mercury body burden, followed by mysids. This paper highlights the importance of suprabenthic peracarida as a vehicle of mercury transference through the estuarine trophic web since it is a main link between benthic and pelagic levels and an essential food resource for numerous fish species.
显示更多 [+] 显示较少 [-]The effects of mercury on the dynamics of the peracarida community in a temperate coastal lagoon (Ria de Aveiro, Portugal)
Valuing the European ‘coastal blue carbon’ storage benefit 全文
2013
Luisetti, T. | Jackson, E.L. | Turner, R.K.
‘Blue’ carbon ecosystems are important carbon storage providers that are currently not protected by any international mechanism, such as REDD. This study aims to contribute to raising awareness in the political domain about the ‘blue’ carbon issue. This analysis also provides guidance in terms of how to value stock and flows of ecosystem services adding to the debate begun by the Costanza et al. (1997) paper in Nature. Through scenario analysis we assess how human welfare benefits will be affected by changes in the European coastal blue carbon stock provision. The current extent of European coastal blue carbon has an accounting stock value of about US$180million. If EU Environmental Protection Directives continue to be implemented and effectively enforced, society will gain an appreciating asset over time. However, a future policy reversal resulting in extensive ecosystem loss could mean economic value losses as high as US$1billion by 2060.
显示更多 [+] 显示较少 [-]The role of highly sratified nutrient-rich small estuaries as a source of dissolved inorganic nitrogen to coastal seawater, the Qishon (SE Mediterranean) case 全文
2013
Eliani-Russak, Efrat | Herut, Barak | Sivan, Orit
We studied the role of small, highly stratified, sulfate and nutrient enriched estuaries, as a source or sink of inorganic nitrogen species, using the Qishon estuary at the Mediterranean coast of Israel, as a case study. Measurements of nutrient concentrations, δ15N and δ18O of nitrate+nitrite, δ13CDIC and δ18OH2O were performed during 2008–2009 along the upper-fresh and lower-saline water masses, as well as sediment porewater depth-profiles. Such estuaries are characterized by relatively low removal flux of NO3- (via sedimentary denitrification) and enhanced (×3) upward flux of NH4+ (via sulfate reduction), attributed to the penetration of seawater of low NO3- and high dissolved oxygen and sulfate concentrations. The role of such small estuaries in releasing dissolved inorganic nitrogen, especially in sensitive oligotrophic areas as the Levantine basin and in the long-term, as a result of enhanced seawater penetration due to the expected sea level rise, has important environmental policy implications.
显示更多 [+] 显示较少 [-]Distribution of sea urchins living near shallow water CO2 vents is dependent upon species acid–base and ion-regulatory abilities 全文
2013
Calosi, P. | Rastrick, S.P.S. | Graziano, M. | Thomas, S.C. | Baggini, C. | Carter, H.A. | Hall-Spencer, J.M. | Milazzo, M. | Spicer, J.I.
Distribution of sea urchins living near shallow water CO2 vents is dependent upon species acid–base and ion-regulatory abilities 全文
2013
Calosi, P. | Rastrick, S.P.S. | Graziano, M. | Thomas, S.C. | Baggini, C. | Carter, H.A. | Hall-Spencer, J.M. | Milazzo, M. | Spicer, J.I.
To reduce the negative effect of climate change on Biodiversity, the use of geological CO2 sequestration has been proposed; however leakage from underwater storages may represent a risk to marine life. As extracellular homeostasis is important in determining species’ ability to cope with elevated CO2, we investigated the acid–base and ion regulatory responses, as well as the density, of sea urchins living around CO2 vents at Vulcano, Italy. We conducted in situ transplantation and field-based laboratory exposures to different pCO2/pH regimes. Our results confirm that sea urchins have some ability to regulate their extracellular fluid under elevated pCO2. Furthermore, we show that even in closely-related taxa divergent physiological capabilities underlie differences in taxa distribution around the CO2 vent. It is concluded that species distribution under the sort of elevated CO2 conditions occurring with leakages from geological storages and future ocean acidification scenarios, may partly be determined by quite subtle physiological differentiation.
显示更多 [+] 显示较少 [-]Distribution of sea urchins living near shallow water CO2 vents is dependent upon species acid-base and ion-regulatory abilities 全文
2013
Calosi, Piero | Rastrick, S P S | Graziano, M | Thomas, S C | Baggini, Cecilia | Carter, H A | Hall-Spencer, Jason M | Milazzo, Marco | Spicer, John I
Ecology of the ciguatera causing dinoflagellates from the Northern Great Barrier Reef: Changes in community distribution and coastal eutrophication 全文
2013
Skinner, Mark P. | Lewis, Richard J. | Morton, Steve
Ciguatera fish poisoning (CFP) is known to be caused by the ciguatoxins from the dinoflagellate genus Gambierdiscus, however, there is the potential for other toxins such as okadaic acid and dinophysistoxins from the genus Prorocentrum, and palytoxin from the genus Ostreopsis, to contaminate seafood. These genera may also be indicators of ecosystem health and potentially impact on coral reef ecosystems and the role they may play in the succession of coral to macroalgae dominated reefs has not been researched. Sixteen GBR field sites spanning inshore, mid-lagoon and outer lagoon (offshore) regions were studied. Samples were collected from September 2006 to December 2007 and abundance of benthic dinoflagellates on different host macroalgae and concentration of nutrients present in the water column were determined. The maximum abundance of Prorocentrum, Ostreopsis and Gambierdiscus found was 112, 793 and 50 cells per gram wet weight of host macroalgae, respectively. The average level of Dissolved Inorganic Nitrogen (DIN) in the water column across all sites (0.03mg/L) was found to be more than double the threshold critical value (0.013mg/L) for healthy coral reefs. Compared to a previous study 1984, there is evidence of a major shift in the distribution and abundance of these dinoflagellates. Inshore reefs have either of Prorocentrum (as at Green Island) or Ostreopsis (as at Magnetic Island) dominating the macroalgal surface niche which was once dominated by Gambierdiscus, whilst at offshore regions Gambierdiscus is still dominant. This succession may be linked to the ongoing eutrophication of the GBR lagoon and have consequences for the sources of toxins for ongoing cases of ciguatera.
显示更多 [+] 显示较少 [-]Shrimp pond effluent dominates foliar nitrogen in disturbed mangroves as mapped using hyperspectral imagery 全文
2013
Fauzi, Anas | Skidmore, Andrew K. | Gils, Hein van | Schlerf, Martin | Heitkönig, Ignas M.A.
Conversion of mangroves to shrimp ponds creates fragmentation and eutrophication. Detection of the spatial variation of foliar nitrogen is essential for understanding the effect of eutrophication on mangroves. We aim (i) to estimate nitrogen variability across mangrove landscapes of the Mahakam delta using airborne hyperspectral remote sensing (HyMap) and (ii) to investigate links between the variation of foliar nitrogen mapped and local environmental variables. In this study, multivariate prediction models achieved a higher level of accuracy than narrow-band vegetation indices, making multivariate modeling the best choice for mapping. The variation of foliar nitrogen concentration in mangroves was significantly influenced by the local environment: (1) position of mangroves (seaward/landward), (2) distance to the shrimp ponds, and (3) predominant mangrove species. The findings suggest that anthropogenic disturbances, in this case shrimp ponds, influence nitrogen variation in mangroves. Mangroves closer to the shrimp ponds had higher foliar nitrogen concentrations.
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