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Likely effects of construction of Scroby Sands offshore wind farm on a mixed population of harbour Phoca vitulina and grey Halichoerus grypus seals Texto completo
2012
Skeate, Eleanor R. | Perrow, Martin R. | Gilroy, James J.
Scroby Sands offshore wind farm was built close to a haul-out and breeding site for harbour seal, a species of conservation concern. An aerial survey programme conducted during a five-year period spanning wind farm construction, revealed a significant post-construction decline in haul-out counts. Multivariate model selection suggested that the decline was not related to the environmental factors considered, nor did it mirror wider population trends. Although cause and effect could not be unequivocally established, the theoretical basis of hearing in pinnipeds and previous studies suggested that extreme noise (to 257dB re 1μ Paₚₚ @ 1m) generated by pile-driving of turbine bases led to displacement of seals. A lack of full recovery of harbour seal during the study was also linked to their sensitivity to vessel activity and/or rapid colonisation of competing grey seal. Any impact of offshore wind farm development upon pinnipeds would be much reduced without pile-driving.
Mostrar más [+] Menos [-]A marine secondary producer respires and feeds more in a high CO₂ ocean Texto completo
2012
Li, Wei | Gao, Kunshan
A marine secondary producer respires and feeds more in a high CO₂ ocean Texto completo
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 [-]Seawater carbonate chemistry and copepod Centropages tenuiremis feeding, filtering and respiration rate during experiments, 2012 Texto completo
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 (>1700 µatm, pH < 7.60) with avoidance strategy. The copepod's respiration increased at the elevated CO2 (1000 µatm), 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 [-]Boring crustaceans damage polystyrene floats under docks polluting marine waters with microplastic Texto completo
2012
Davidson, Timothy M.
Boring isopods damage expanded polystyrene floats under docks and, in the process, expel copious numbers of microplastic particles. This paper describes the impacts of boring isopods in aquaculture facilities and docks, quantifies and discusses the implications of these microplastics, and tests if an alternate foam type prevents boring. Floats from aquaculture facilities and docks were heavily damaged by thousands of isopods and their burrows. Multiple sites in Asia, Australia, Panama, and the USA exhibited evidence of isopod damage. One isopod creates thousands of microplastic particles when excavating a burrow; colonies can expel millions of particles. Microplastics similar in size to these particles may facilitate the spread of non-native species or be ingested by organisms causing physical or toxicological harm. Extruded polystyrene inhibited boring, suggesting this foam may prevent damage in the field. These results reveal boring isopods cause widespread damage to docks and are a novel source of microplastic pollution.
Mostrar más [+] Menos [-]Polycyclic aromatic hydrocarbons loads into the Mediterranean Sea: Estimate of Sarno River inputs Texto completo
2012
Montuori, Paolo | Triassi, Maria
The polycyclic aromatic hydrocarbons (PAHs) pollution in the Sarno River and its environmental impact on the Gulf of Naples (Tyrrhenian Sea, Central Mediterranean Sea) were estimated. The 16 PAHs identified by the USEPA as priority pollutants and perylene were determined in the water dissolved phase (DP), suspended particulate matter (SPM) and sediments. Total PAHs concentrations ranged from 23.1 to 2670.4ngL⁻¹ in water (sum of DP and SPM) and from 5.3 to 678.6ngg⁻¹ in sediment samples. Source analysis revealed that PAHs mainly came from combustion process. Contaminant discharges of PAHs into the sea were calculated in about 8530gd⁻¹ showing that this river should account as one of the main contribution sources of PAHs to the Tyrrhenian Sea.
Mostrar más [+] Menos [-]The impact of coastal urbanization on the structure of phytobenthic communities in southern Brazil Texto completo
2012
Martins, Cintia D.L. | Arantes, Noele | Faveri, Caroline | Batista, Manuela B. | Oliveira, Eurico C. | Pagliosa, Paulo R. | Fonseca, Alessandra L. | Nunes, José Marcos C. | Chow, Fungyi | Pereira, Sonia B. | Horta, Paulo A.
The impact of coastal urbanization on the structure of phytobenthic communities in southern Brazil Texto completo
2012
Martins, Cintia D.L. | Arantes, Noele | Faveri, Caroline | Batista, Manuela B. | Oliveira, Eurico C. | Pagliosa, Paulo R. | Fonseca, Alessandra L. | Nunes, José Marcos C. | Chow, Fungyi | Pereira, Sonia B. | Horta, Paulo A.
The anthropogenic pressures on coastal areas represent important factors affecting local, regional, and even global patterns of distribution and abundance of benthic organisms. This report undertakes a comparative analysis of the community structure of rocky shore intertidal phytobenthos in both pristine like environments (PLE) and urbanized environments (UBE) in southern Brazil, characterizing variations on different spatial scales. Multivariate analysis of variance indicated that the PLE is characterized by a larger number of taxa and an increased occurrence of Rhodophyta species in relation to UBE. In contrast, UBE were dominated by opportunistic algae, such as Cladophora and Ulva spp. Significance tests further indicated higher species richness and Shannon–Wiener diversity on the PLE in relation to UBE. Here we provide data showing the magnitude of seaweed biodiversity loss and discuss direct and indirect consequences of unplanned urbanization on these communities.
Mostrar más [+] Menos [-]The impact of coastal urbanization on the structure of phytobenthic communities in southern Brazil | Marine Pollution Bulletin Texto completo
2012
Martins, Cintia D. L. | Arantes, Noele | Faveri, Caroline | Batista, Manuela B. | Oliveira, Eurico C. | Pagliosa, Paulo R. | Fonseca, Alessandra L. | Nunes, José Marcos de Castro | Chow, Fungyi | Pereira, Sônia Maria Barreto | Horta, Paulo A. | Martins, Cintia D. L. | Arantes, Noele | Faveri, Caroline | Batista, Manuela B. | Oliveira, Eurico C. | Pagliosa, Paulo R. | Fonseca, Alessandra L. | Nunes, José Marcos de Castro | Chow, Fungyi | Pereira, Sônia Maria Barreto | Horta, Paulo A.
Texto completo: acesso restrito. p. 772–778 | The anthropogenic pressures on coastal areas represent important factors affecting local, regional, and even global patterns of distribution and abundance of benthic organisms. This report undertakes a comparative analysis of the community structure of rocky shore intertidal phytobenthos in both pristine like environments (PLE) and urbanized environments (UBE) in southern Brazil, characterizing variations on different spatial scales. Multivariate analysis of variance indicated that the PLE is characterized by a larger number of taxa and an increased occurrence of Rhodophyta species in relation to UBE. In contrast, UBE were dominated by opportunistic algae, such as Cladophora and Ulva spp. Significance tests further indicated higher species richness and Shannon–Wiener diversity on the PLE in relation to UBE. Here we provide data showing the magnitude of seaweed biodiversity loss and discuss direct and indirect consequences of unplanned urbanization on these communities.
Mostrar más [+] Menos [-]Distribution and sources of aliphatic hydrocarbons in surface sediments of Sergipe River estuarine system Texto completo
2012
Lima, Manoel B. | Feitosa, Elaine A. | Emídio, Elissandro S. | Dórea, Haroldo S. | Alexandre, Marcelo R.
The assessment of aliphatic hydrocarbons was performed in the Sergipe River estuarine system, northeastern Brazil. Aliphatic hydrocarbons concentration ranged from 9.9ugg⁻¹ up to 30.8ugg⁻¹ of dry sediment. The carbon preference index (CPI, based on nC₂₄ to nC₃₄ range), indicated predominance of petrogenic input in two of the sites analyzed (P4 and P5). The unresolved complex mixture (UCM) was found to be present in seven of the nine sites sampled (except for P4 and P5). Overall, the results of this work suggest that there is a mix of organic matter sources to the sediment. Although the coast of Sergipe has an intense off shore petroleum exploration and the Sergipe River crosses the entire city of Aracaju, the capital city of Sergipe, non-significant anthropogenic fingerprint was assessed.
Mostrar más [+] Menos [-]Influence of strong monsoon winds on the water quality around a marine cage-culture zone in a shallow and semi-enclosed bay in Taiwan Texto completo
2012
Huang, Yuan-Chao Angelo | Huang, Shou-Chung | Meng, Pei-Jie | Hsieh, Hernyi Justin | Chen, Chaolun Allen
Influences of marine cage culture and monsoonal disturbances, northeasterly (NE) and southwesterly (SW) monsoons on the proximal marine environment were investigated across a gradient of sites in a semi-enclosed bay, Magong Bay (Penghu Islands, Taiwan). Elevated levels of ammonia produced by the cages were the main pollutant and distinguished the cage-culture and intermediary zones (1000m away from the cages) from the reference zone in the NE monsoon, indicating currents produced by the strong monsoon may have extended the spread of nutrient-enriched waters without necessarily flushing such effluents outside Magong Bay. Moreover, the levels of chlorophyll-a, dissolved oxygen, and turbidity were distinguishable between two seasons, suggesting that resuspension caused by the NE monsoon winds may also influence the water quality across this bay. It indicated that the impacts of marine cage culture vary as a function of distance, and also in response to seasonal movements of water driven by local climatic occurrences.
Mostrar más [+] Menos [-]Genotoxicity and development effects of brominated flame retardant PBDEs and UV-exposed PBDEs on grass shrimp (Palaemonetes pugio) embryo Texto completo
2012
Lee, Hyo Jin | Kim, Gi Beum | Lee, Richard F.
To understand how polybrominated diphenyl ethers (PBDEs) affect the hatching sensitivity of grass shrimp embryos in different developmental stages, the hatching rates of embryos were measured after PBDE exposure on the early- and late-stage embryo of grass shrimp. PBDEs had no clear influence on the hatching rate. Also, to investigate on the reproductive and genetic toxicities of UV-exposed PBDEs, the hatching rate and DNA damage of stage 7 embryos were also measured. PBDEs had no significant impact on the hatching rate and DNA damage of grass shrimp in most experimental conditions regardless of embryo developmental stage or UV exposure, but in the case of UV-exposed BDE-47, the hatching rate was decreased, suggesting a potential reproductive toxicity. This research is meaningful because it is the first study to propose that PBDEs can cause reproductive toxicity in marine organism, after flowing into the ocean and undergoing photochemical reactions stimulated by UV.
Mostrar más [+] Menos [-]A comparative study on the effects of barite, ilmenite and bentonite on four suspension feeding bivalves Texto completo
2012
F. Strachan, Maia | F. Kingston, Paul
The impact of drilling mud components on the filtration activity and survival of bivalve molluscs was investigated by exposing them to suspensions of ‘standard’ barite, finely milled barite, ilmenite and bentonite in sea water. Introduction of the components stimulated filtration activity in all four bivalves. In addition, the introduction of standard barite and ilmenite both had lethal effects, with none of the bivalves surviving the full duration of the experiments. In-vivo observations of the gill surfaces provided direct evidence of physical damage caused by the administration of barite and ilmenite. A marked difference between filtration activity and survival of animals dosed with ‘standard’ barite and ‘fine’ barite suggests that the observed effects were primarily caused by physical interference with gill function. The results also suggest that the use of fine barite in offshore drilling may provide a more favourable environmental impact profile than the use of ilmenite.
Mostrar más [+] Menos [-]Severe pollution of PCDD/Fs and dioxin-like PCBs in sediments from Lake Shihwa, Korea: Tracking the source Texto completo
2012
Moon, Hyo-Bang | Choi, Minkyu | Choi, Hee-Gu | Kannan, Kurunthachalam
Concentrations of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) were determined in surface sediments from Lake Shihwa and from creeks that discharge into this artificial lake. The toxic equivalents (TEQs) in sediments ranged from 1.0 to 1770pg/g dry weight, which were some of the highest values ever reported so far for coastal sediments on a global basis. The concentrations of PCDD/Fs and DL-PCBs decreased with increasing distance from the creeks to offshore regions of the lake. Based on a multivariate statistical analysis and congener profiles, it was found that high contamination by PCDD/Fs in creek sediments collected around Lake Shihwa was associated with releases from chlor-alkali processes. Significant correlations were found for total organic carbon content and the concentrations of highly chlorinated PCDD/F congeners. This is the first report to document chlor-alkali processes as a significant source of PCDD/F contamination in Korean coastal waters.
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