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Impact of aquaculture and agriculture nutrient sources on macroalgae in a bioassay study | Impact of aquaculture and agriculture nutrient sources on macroalgae in a bioassay study
2021
Streicher, Michael Daniel | Reiss, Henning | Reiss, Katrin
Eutrophication is a major threat to aquatic ecosystems, because excessive nutrient enrichment may result in the loss of ecosystem services. Fjord systems are specifically under pressure due to nutrient input from land (agriculture) and sea (aquaculture). In this bioassay study, we have analyzed the effect of different nutrient sources, as well as their combination, on growth, nutrient composition and recruitment of habitat-forming and ephemeral macrophytes. We found that agricultural fertilizer increased growth for all algae (except Fucus), while the fish farm effluents mainly increased growth of Ulva. The C:N ratio was hardly affected by the fish farm, but decreased significantly in all algae when agriculture fertilizer was added. Most interestingly, however, distance to the fish farm modulated the algal response to the fertilizer. Our results demonstrate the importance of studying effects of multiple stressors in aquatic ecosystems to sustainably manage the consequences of anthropogenic impacts. | publishedVersion
Mostrar más [+] Menos [-]Changes to an urban marina soundscape associated with COVID-19 lockdown in Guadeloupe
2021
Bertucci, Frédéric | Lecchini, David | Greeven, Céline | Brooker, Rohan M | Minier, Lana | Cordonnier, Sébastien | René-Trouillefou, Malika | Parmentier, Eric
peer reviewed
Mostrar más [+] Menos [-]Modeling the toxicity of dissolved crude oil exposures to characterize the sensitivity of cod (Gadus morhua) larvae and role of individual and unresolved hydrocarbons
2019
Hansen, Bjørn Henrik | Parkerton, Thomas F. | Nordtug, Trond | Størseth, Trond Røvik | Redman, Aaron D.
Toxicity of weathered oil was investigated using Atlantic cod (Gadus morhua) larvae. A novel exposure system was applied to differentiate effects associated with dissolved and droplet oil with and without dispersant. After a 4-day exposure and subsequent 4-day recovery period, survival and growth were determined. Analytical data characterizing test oil composition included polyaromatic hydrocarbons (PAH) based on GC/MS and unresolved hydrocarbon classes obtained by two-dimensional chromatography coupled with flame ionization detection was used as input to an oil solubility model to calculate toxic units (TUs) of dissolved PAHs and whole oil, respectively. Critical target lipid body burdens derived from modeling characterizing the sensitivity of effect endpoints investigated were consistent across treatments and within the range previously reported for pelagic species. Individually measured PAHs captured only 3–11% of the TUs associated with the whole oil highlighting the limitations of traditional total PAH exposure metrics for expressing oil toxicity data. | acceptedVersion
Mostrar más [+] Menos [-]Microplastics in grey seal (Halichoerus grypus) intestines: Are they associated with parasite aggregations?
2019
Hernandez-Milian, G | Lusher, A | MacGabban, S | Rogan, E
Embargo until 28 June 2021 | Between 2012 and 2015, 13 grey seals were recovered from trammel nets targeting monkfish and rays off the south coast of Ireland. Incidence and distribution of microplastics were investigated along the intestines of bycaught seals. No macrodebris items were found, whereas microplastics were detected in all seals. A total of 363 microplastics items were identified (85% fibers, 14% fragments, 1% films). Estimation of microplastic ingestion based on prey ingestion (245 particles) was lower than the observed data. Acantocephala parasites (n = 1543) were found in 12 seals, with an average of 74.5 ± 67.7 parasites per seal. Distribution of microplastics varied between seals, although microplastics tended to accumulate in areas where more parasites were aggregated; however, there was no significant relationship between the number of parasites and microplastics was found. Seals recovered from nets appear to be a good source to monitor the incidence of microplastic pollution within the coastal food webs. | acceptedVersion
Mostrar más [+] Menos [-]Ecological risk assessment to marine organisms induced by heavy metals in China's coastal waters
2018
Wang, Mengzhu | Tong, Yindong | Chen, Cen | Liu, Xianhua | Lu, Yiren | Zhang, Wei | He, Wei | Wang, Xuejun | Zhao, Shen | Lin, Yan
Embargo until 23 November 2019 | China's coastal environment has been heavily affected by the loading of terrestrial pollutants in recent decades, and quantitative risk assessment is urgently needed to assess the ecological risks of China's coastal environment. We assessed the ecological risks induced by five heavy metals (including Cu, Zn, Pb, Hg and As) in China's coastal waters for three groups of marine organisms (including crustacean, fish and mollusc) based on data obtained from a nationwide unified coastal environment monitoring program consisting of 301 sampling sites. The results show that higher heavy metal concentrations occurred more frequently in the Bohai Sea and in the estuaries of major sea-going rivers. The ecological risks decreased in the following order: Bohai Sea > Yellow Sea > South China Sea > East China Sea. There was generally low ecological risk, but certain hotspots existed near Tianjin and Jinzhou, which had relatively high ecological risks caused by Cu and Zn. | acceptedVersion
Mostrar más [+] Menos [-]Petroleum hydrocarbon and microbial community structure successions in marine oil-related aggregates associated with diatoms relevant for Arctic conditions
2018
Netzer, Roman | Henry, Ingrid Annemarie | Ribicic, Deni | Wibberg, Daniel | Brönner, Ute | Brakstad, Odd Gunnar
Oil-related aggregates (ORAs) may contribute to the fate of oil spilled offshore. However, our understanding about the impact of diatoms and associated bacteria involved in the formation of ORAs and the fate of oil compounds in these aggregates is still limited. We investigated these processes in microcosm experiments with defined oil dispersions in seawater at 5 °C, employing the Arctic diatom Fragilariopsis cylindrus and its associated bacterial assemblage to promote ORA formation. Accumulation of oil compounds, as well as biodegradation of naphthalenes in ORAs and corresponding water phases, was enhanced in the presence of diatoms. Interestingly, the genus Nonlabens was predominating the bacterial communities in diatom-supplemented microcosms, while this genus was not abundant in other samples. This work elucidates the relevance of diatom biomass for the formation of ORAs, microbial community structures and biodegradation processes in chemically dispersed oil at low temperatures relevant for Arctic conditions. | acceptedVersion
Mostrar más [+] Menos [-]Spreading of waxy Crude Oils on calm weather | Spreading of waxy Crude Oils on calm weather
2018
Brönner, Ute | Johansen, Øistein | Leirvik, Frode | Nordam, Tor | Sørheim, Kristin Rist
The objective of this paper is to provide a simple extension of the much-used gravity spreading model for oil on calm water to account for the spreading behavior of waxy crude oils in cold waters – including the observed retardation and eventual termination of spreading at certain oil film thicknesses. This peculiar behavior is not predicted by traditional spreading models for oil on calm water (i.e. viscous-gravity spreading models), but may occur due to non-Newtonian oil properties caused by precipitation of wax at low temperatures. To clarify the spreading behavior of such oils, SINTEF has conducted a series of laboratory experiments with a range of waxy oil mixtures. The present paper contains analyses of data from these experiments, including favorable comparisons with calculations by a proposed improved surface spreading model. | Spreading of waxy Crude Oils on calm weather | acceptedVersion
Mostrar más [+] Menos [-]The sensitivity of the surface oil signature to subsurface dispersant injection and weather conditions
2018
Daae, Ragnhild Lundmark | Skancke, Jørgen | Brandvik, Per Johan | Faksness, Liv Guri
Subsea blowouts have the potential to spread oil across large geographical areas, and subsea dispersant injection (SSDI) is a response option targeted at reducing the impact of a blowout, especially reducing persistent surface oil slicks. Modified Weber scaling was used to predict oil droplet sizes with the OSCAR oil spill model, and to evaluate the surface oil volume and area when using SSDI under different conditions. Generally, SSDI reduces the amount of oil on the surface, and creates wider and thinner surface oil slicks. It was found that the reduction of surface oil area and volume with SSDI was enhanced for higher wind speeds. Overall, given the effect of SSDI on oil volume and weathering, it may be suggested that tar ball formation, requiring thick and weathered oil, could possibly be reduced when SSDI is used. | acceptedVersion
Mostrar más [+] Menos [-]Vitellogenin and vitellogenin receptor gene expression and 20-hydroxyecdysone concentration in Macrobrachium rosenbergii exposed to chlordecone
2016
Lafontaine, Anne | Hanikenne, Marc | Boulangé-Lecomte, Céline | Forget-Leray, Joëlle | Thomé, Jean-Pierre | Gismondi, Eric
peer reviewed
Mostrar más [+] Menos [-]L’azote, si cher à nos campagnes
2016
Génermont, Sophie, | Cellier, Pierre
L’azote, si cher à nos campagnes
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