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Metazooplankton communities in the Ahe atoll lagoon (Tuamotu Archipelago, French Polynesia): Spatiotemporal variations and trophic relationships 全文
2012
Pagano, Marc | Sagarra, Pascual-Boi | Champalbert, Gisèle | Bouvy, Marc | Dupuy, Christine | Thomas, Yoann | Charpy, Loïc
Metazooplankton communities in the Ahe atoll lagoon (Tuamotu Archipelago, French Polynesia): Spatiotemporal variations and trophic relationships 全文
2012
Pagano, Marc | Sagarra, Pascual-Boi | Champalbert, Gisèle | Bouvy, Marc | Dupuy, Christine | Thomas, Yoann | Charpy, Loïc
Metazooplankton abundance, biomass (<80μm, 200–500μm and >500μm) and community structure in the Ahe atoll were studied together with their relationships with environmental factors (temperature, salinity, wind) and trophic factors (phytoplankton, bacteria, heterotrophic nanoflagellates (HNF) and ciliates) during three periods in 2008–2009. Meroplankton, mainly bivalve and gastropod larvae, was dominant. Holoplankton was dominated by copepods, the main species being Oithona spp., Paracalanus parvus, Clausocalanus spp., Corycaeus spp., Acartia fossae and Undinula vulgaris. The results suggest a clear wind influence on the structure and horizontal distribution of the zooplankton communities. The metazooplankton appeared to be controlled mainly by food resources, suggesting a bottom-up control. The low nanophytoplankton biomass in contrast to the high abundance of picophytoplankton, HNF and nano-particle grazers (mainly Oithona spp., Paracalanus and bivalve larvae) highlighted the importance of the microbial loop in the food web.
显示更多 [+] 显示较少 [-]Metazooplankton communities in the Ahe atoll lagoon (Tuamotu Archipelago, French Polynesia): Spatiotemporal variations and trophic relationships 全文
2012
Pagano, Marc | Sagarra, Pascual-boi | Champalbert, Gisele | Bouvy, Marc | Dupuy, Christine | Thomas, Yoann | Charpy, Loic
Metazooplankton abundance, biomass (<80 mu m, 200-500 mu m and >500 mu m) and community structure in the Ahe atoll were studied together with their relationships with environmental factors (temperature, salinity, wind) and trophic factors (phytoplankton, bacteria, heterotrophic nanoflagellates (HNF) and ciliates) during three periods in 2008-2009. Meroplankton, mainly bivalve and gastropod larvae, was dominant. Holoplankton was dominated by copepods, the main species being Oithona spp., Paracalanus parvus, Clausocalanus spp., Corycaeus spp., Acartia fossae and Undinula vulgaris. The results suggest a clear wind influence on the structure and horizontal distribution of the zooplankton communities. The metazooplankton appeared to be controlled mainly by food resources, suggesting a bottom-up control. The low nanophytoplankton biomass in contrast to the high abundance of picophytoplankton, HNF and nano-particle grazers (mainly Oithona spp., Paracalanus and bivalve larvae) highlighted the importance of the microbial loop in the food web. (C) 2012 Elsevier Ltd. All rights reserved.
显示更多 [+] 显示较少 [-]Use of aliphatic hydrocarbons to infer terrestrial organic matter in coastal marine sediments off China 全文
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.
显示更多 [+] 显示较少 [-]Seagrass burial by dredged sediments: Benthic community alteration, secondary production loss, biotic index reaction and recovery possibility 全文
2012
Tu Do, V. | de Montaudouin, Xavier | Blanchet, Hugues | Lavesque, Nicolas
In 2005, dredging activities in Arcachon Bay (France) led in burying 320,000m² of Zostera noltii intertidal seagrass. Recovery by macrobenthos and seagrass was monitored. Six months after works, seagrass was absent and macrobenthos drastically different from surrounding vegetated stations. Rapidly and due to sediment dispersal, disposal area was divided into a sandflat with a specific benthic community which maintained its difference until the end of the survey (2010), and a mudflat where associated fauna became similar to those in adjacent seagrass. Macrobenthic community needs 3years to recover while seagrass needs 5years to recover in the station impacted by mud. The secondary production loss due to works was low. In this naturally carbon enriched system, univariate biotic indices did not perform well to detect seagrass destruction and recovery. Multivariate index MISS gave more relevant conclusions and a simplified version was tested with success, at this local scale.
显示更多 [+] 显示较少 [-]Tolerance and accumulation of copper in the salt-marsh shrub Halimione portulacoides 全文
2012
Cambrollé, J. | Mancilla-Leytón, J.M. | Muñoz-Vallés, S. | Luque, T. | Figueroa, M.E.
Tolerance and accumulation of copper in the salt-marsh shrub Halimione portulacoides 全文
2012
Cambrollé, J. | Mancilla-Leytón, J.M. | Muñoz-Vallés, S. | Luque, T. | Figueroa, M.E.
The present study evaluated the tolerance and accumulation potential in the salt-marsh shrub Halimione portulacoides under moderate and high external Cu levels. A greenhouse experiment was conducted in order to investigate the effects of a range of external Cu concentrations (0 to 60mmoll⁻¹) on growth and photosynthetic performance by measuring gas exchange, chlorophyll fluorescence parameters and photosynthetic pigments. We also determined total copper, nitrogen, phosphorus and sulfur concentrations in the plant tissues. H. portulacoides survived with external Cu concentrations of up to 35mmolCul⁻¹, although the excess of metal resulted in a biomass reduction of 48%. The effects of Cu on growth were linked to a drastic reduction in net photosynthesis. However, H. portulacoides tolerated Cu levels of up to 15mmolCul⁻¹ without suffering adverse physiological effects. Our results indicate that this species could play an important role in the restoration of Cu-contaminated soils.
显示更多 [+] 显示较少 [-]Tolerance and accumulation of copper in the salt-marsh shrub Halimione portulacoides 全文
2012
Cambrollé Silva, Jesús | Mancilla Leytón, Juan Manuel | Muñoz Vallés, Sara | Luque Palomo, María Teresa | Figueroa Clemente, Manuel Enrique | Universidad de Sevilla. Departamento de Biología Vegetal y Ecología | Universidad de Sevilla. Departamento de Agronomía
The present study evaluated the tolerance and accumulation potential in the salt-marsh shrub Halimione portulacoides under moderate and high external Cu levels. A greenhouse experiment was conducted in order to investigate the effects of a range of external Cu concentrations (0 to 60 mmol l−1) on growth and photosynthetic performance by measuring gas exchange, chlorophyll fluorescence parameters and photosynthetic pigments. We also determined total copper, nitrogen, phosphorus and sulfur concentrations in the plant tissues. H. portulacoides survived with external Cu concentrations of up to 35 mmol Cu l−1, although the excess of metal resulted in a biomass reduction of 48%. The effects of Cu on growth were linked to a drastic reduction in net photosynthesis. However, H. portulacoides tolerated Cu levels of up to 15 mmol Cu l−1 without suffering adverse physiological effects. Our results indicate that this species could play an important role in the restoration of Cu-contaminated soils.
显示更多 [+] 显示较少 [-]Microbiological and physicochemical analysis of the coastal waters of southern Brazil 全文
2012
Moresco, V. | Viancelli, A. | Nascimento, M.A. | Souza, D.S.M. | Ramos, A.P.D. | Garcia, L.A.T. | Simões, C.M.O. | Barardi, C.R.M.
Microbiological and physicochemical analysis of the coastal waters of southern Brazil 全文
2012
Moresco, V. | Viancelli, A. | Nascimento, M.A. | Souza, D.S.M. | Ramos, A.P.D. | Garcia, L.A.T. | Simões, C.M.O. | Barardi, C.R.M.
The aim of this study was to assess the impact of sewage discharge on coastal waters by evaluating the influence of physicochemical parameters on the presence of enteric microorganisms in seawater samples collected from 11 beaches in Florianopolis, Santa Catarina, Brazil, over a one-year period (August 2009 to July 2010). Samples were assessed for the presence of human adenoviruses (HAdV), polyomavirus (JCPyV), hepatitis A virus (HAV), and noroviruses (HuNoV GI and GII). Escherichia coli and physicochemical parameters (salinity, temperature, pH and dissolved oxygen) were also evaluated. From the 132 samples analyzed, 55% were positive for HAdV, 51.5% for HAV, 7.5% for HuNoV GI, 4.5% for HuNoV GII, and 3% for JCPyV. E. coli levels ranged from 8 to 1325CFU/100mL at all sites. The overall results highlight the problem of sewage discharge into coastal waters and confirm that there is no correlation between viral presence and bacterial contamination.
显示更多 [+] 显示较少 [-]Microbiological and physicochemical analysis of the coastal waters of southern Brazil 全文
2021 | 2011 | 2012
Moresco, Vanessa | Viancelli, Aline | Nascimento, Mariana de Almeida do | Souza, Doris Sobral Marques | Ramos, Ana Paula Dores | Garcia, Lucas Ariel Totaro | Simões, Claudia Maria de Oliveira | Barardi, Celia Regina Monte | CAPES | CNPq | MAPA | Federal University of Santa Catarina, Brazil | Federal University of Santa Catarina, Brazil | Federal University of Santa Catarina, Brazil | Federal University of Santa Catarina, Brazil | Federal University of Santa Catarina, Brazil | Federal University of Santa Catarina, Brazil | Federal University of Santa Catarina, Brazil | Federal University of Santa Catarina, Brazil | 0000-0002-8699-8179
The aim of this study was to assess the impact of sewage discharge on coastal waters by evaluating the influence of physicochemical parameters on the presence of enteric microorganisms in seawater samples collected from 11 beaches in Florianopolis, Santa Catarina, Brazil, over a one-year period (August 2009 to July 2010). Samples were assessed for the presence of human adenoviruses (HAdV), polyomavirus (JCPyV), hepatitis A virus (HAV), and noroviruses (HuNoV GI and GII). Escherichia coli and physicochemical parameters (salinity, temperature, pH and dissolved oxygen) were also evaluated. From the 132 samples analyzed, 55% were positive for HAdV, 51.5% for HAV, 7.5% for HuNoV GI, 4.5% for HuNoV GII, and 3% for JCPyV. E. coli levels ranged from 8 to 1325 CFU/100 mL at all sites. The overall results highlight the problem of sewage discharge into coastal waters and confirm that there is no correlation between viral presence and bacterial contamination.
显示更多 [+] 显示较少 [-]Deep-sea foraminifera from the Cassidaigne Canyon (NW Mediterranean): Assessing the environmental impact of bauxite red mud disposal 全文
2012
Fontanier, C. | Fabri, M.-C. | Buscail, R. | Biscara, L. | Koho, K. | Reichart, G.J. | Cossa, D. | Galaup, S. | Chabaud, G. | Pigot, L.
Benthic foraminiferal assemblages were investigated from two sites along the axis of the Cassidaigne Canyon (NW Mediterranean Sea). Both areas are contaminated by bauxite red mud enriched in iron, titanium, vanadium and chromium. These elemental enrichments are related to bauxite-derived minerals and various amorphous phases. At the shallowest station located very close to the pipe outlet, the benthic living foraminiferal community is characterised by a very low diversity and by an unusual dominance of Gyroidina umbonata and Bulimina marginata. The mechanical stress related to downslope transport of red mud is a likely source of hydro-sedimentary pollution precluding the settlement of diverse fauna. The living and dead foraminiferal faunas from the deepest site are typical of oligo-mesotrophic conditions prevailing in natural environments. There, bauxite residues have obviously no environmental impact on foraminiferal faunas. The bioavailability of trace metals is likely low as elemental enrichments were not observed in foraminiferal test chemistry.
显示更多 [+] 显示较少 [-]Reducing dissolved inorganic nitrogen in surface runoff water from sugarcane production systems 全文
2012
Webster, A.J. | Bartley, R. | Armour, J.D. | Brodie, J.E. | Thorburn, P.J.
Nitrogen (N) lost from farms, especially as the highly bioavailable dissolved inorganic form, may be damaging Australia’s Great Barrier Reef (GBR). As sugarcane is the dominant cropping system in GBR catchments, its N management practises are coming under increasing scrutiny. This study measured dissolved inorganic N lost in surface runoff water and sugarcane productivity over 3years. The experiment compared the conventional fertiliser N application rate to sugarcane (average 180kgN/ha/year) and a rate based on replacing N exported in the previous crop (average 94kgN/ha/year). Dissolved inorganic N losses in surface water were 72%, 48% and 66% lower in the three monitored years in the reduced N fertiliser treatment. There was no significant difference in sugarcane yield between the two fertiliser N treatments, nor any treatment difference in soil mineral N – both of these results are indicators of the sustainability of the lower fertiliser N applications.
显示更多 [+] 显示较少 [-]Onshore ballast water treatment: A viable option for major ports 全文
2012
Pereira, Newton Narciso | Brinati, Hernani Luiz
Ballast water treatment consists of the elimination of exotic species. Currently, the development of alternative methods for this process is directed toward treatment onboard ships. However, we present onshore treatment as a viable alternative for ballast water treatment. We investigated onshore treatment in two iron ore ports with movement capacities of 25 and 90million tons annually (Mta) that receive 7.5 and 25million cubic meters annually (Mm³) of ballast water, respectively. Discrete event simulation was used as the method of analysis, considering the processes of arrival, berthing, ship loading and capture and treatment of ballast water. We analyzed data from 71 ships operating in these ports to validate our simulation model. We were able to demonstrate that onshore treatment does not impact the cargo capacity, occupation rate or average queuing time of ships at these ports. We concluded that implementation of onshore ballast water treatment may be practicable in ports that receive high volumes of ballast water.
显示更多 [+] 显示较少 [-]Overview of the 20th century impact of trace metal contamination in the estuaries of Todos os Santos Bay: Past, present and future scenarios 全文
2012
Hatje, Vanessa | Barros, Francisco
This paper discusses the distribution patterns of trace metals in sediments and suspended particulate matter (SPM) in the three main estuaries of the Todos os Santos Bay (BTS), Brazil, during dry and rainy seasons. Data available up to 2012 was also reviewed to assess the status of contamination. For most elements, metal concentrations in sediments decreased from the tidal limits to the lower estuary. Metals in SPM presented more complex distributions along the salinity gradient. Metal variability between rainy and dry conditions was only significant for SPM data. Of the BTS estuaries, the levels of Cd, Zn, Pb and Cu are highest in the Subaé estuary, and they seem to be promoting harmful biological effects in macrofauna, and also may pose potential human health risks. Despite the evidence of important localized contamination, much of the data compiled indicates that the bay and its estuaries are still relatively preserved.
显示更多 [+] 显示较少 [-]Comparative study of polycyclic aromatic hydrocarbons (PAHs) in plasma of Eastern Atlantic juvenile and adult nesting loggerhead sea turtles (Caretta caretta) 全文
2012
Camacho, Maria | Boada, Luis D. | Orós, Jorge | Calabuig, Pascual | Zumbado, Manuel | Luzardo, Octavio P.
Polycyclic aromatic hydrocarbons (PAHs) were measured in plasma samples of 162 juvenile loggerhead sea turtles (Caretta caretta) from Canary Islands, and 205 adult nesting loggerheads from Cape Verde. All the 367 samples showed detectable values of some type of PAH. Phenanthrene was the PAH most frequently detected and at the highest concentration in both populations. Median concentrations of ∑PAHs in the plasma of loggerheads from the Canary Islands and Cape Verde were similar (5.5 and 4.6ng/ml, respectively). Di- and tri-cyclic PAHs were predominant in both populations suggesting petrogenic origin rather than urban sources of PAHs. In the group of turtles from Canary Islands, there was evident an increasing level of contamination over the last few years. The present study represents the first data of contamination by PAHs in sea turtles from the studied areas.
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