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Registros recuperados: 154 | |
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Piriou, Jean-yves; Chapron, Victorien; Annezo, Jean-pierre. |
The gulf of Morbihan, without manifesting any pronounced signs of eutrophication, has, in 1995, three sites of green algae proliferation: the Auray river estuary, the branches of the Vannes and Séné estuary, as well as the outlet of the Noyalo's estuary. They are also the three sectors of the gulf that receive the most nutrient salts, in particular, nitrogen, which is a determining factor in the development of nitrophilic green algae (Ménesguen and Piriou 1995). During spring the nitrogen seems to come as much from urban sources (Vannes, Auray) as from agricultural sources coming from the northern catchment areas of the gulf. |
Tipo: Text |
Palavras-chave: Morbihan gulf; Eutrophication; Nitrogen; Green seaweed; Green algae; Eutrophisation; Golfe du Morbihan; Azote; Algues vertes. |
Ano: 1995 |
URL: http://archimer.ifremer.fr/doc/1995/rapport-2084.pdf |
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Derolez, Valerie. |
The Thau lagoon is one of the largest Mediterranean coastal lagoons and it supports many uses such as shellfish farming and fishing, priority activities of the territory, and more recently recreational activities. Since the 1960s, the increase in anthropogenic inputs, linked to the sudden growth of the population, led to microbiological contaminations of shellfish and degraded status of the lagoon, with negative impacts at sanitary, ecological and socio‐economic levels. Since the 1970s, the considerable work carried out on the waste water system on the watershed has made it possible to restore the lagoon, which then began an oligotrophication trajectory, a process that has still few been studied in coastal environments. Subject to a variety of pressures... |
Tipo: Text |
Palavras-chave: Lagoon; Eutrophication; Oligotrophication; Ecological status; Ecosystem services; Socio‐ecosystem; Thau.; Lagune; Eutrophisation; Oligotrophisation; État écologique; Services écosystémiques; Socio‐écosystème; Thau.. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00662/77364/78938.pdf |
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Pakhomova, Svetlana; Yakushev, Evgeniy; Protsenko, Elizaveta; Rigaud, Sylvain; Cossa, Daniel; Knoery, Joel; Couture, Raoul-marie; Radakovitch, Olivier; Yakubov, Shamil; Krzeminska, Dominika; Newton, Alice. |
This study presents a specifically designed Mercury module in a coupled benthic-pelagic reactive-transport model - Bottom RedOx Model (BROM) that allows to study mercury (Hg) biogeochemistry under different conditions. This module considers the transformation of elemental mercury (Hg(0)), divalent mercury (Hg(II)) and methylmercury (MeHg). The behavior of mercury species in the model is interconnected with changes of oxygen, hydrogen sulfide, iron oxides, organic matter, and biota. We simulated the transformation and transport of Hg species in the water column and upper sediment layer under five different scenarios, combining various levels of oxygenation and trophic state in the Berre lagoon, a shallow eutrophic lagoon of the French Mediterranean coast... |
Tipo: Text |
Palavras-chave: Mercury; Methylmercury; Biogeochemical modeling; Anoxia; Eutrophication; Lagoon; BROM. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00454/56535/58239.pdf |
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Brehmer, Patrice; Thang Do Chi,; Laugier, Thierry; Galgani, Francois; Laloe, Francis; Darnaude, Audrey M.; Fiandrino, Annie; Mouillot, David. |
1. Abiotic and biotic variables of coastal lagoons are highly heterogeneous in both space and time, and this heterogeneity complicates the assessment of their ecological status. These variables are essential to the monitoring and preservation of these fragile ecotones and the resources and services they sustain. 2. An integrative approach for evaluating the ecological status of coastal lagoons, based on field investigations of the key parameters driving their functioning and a set of selected ecological indicators matching lagoon management information needs for societal benefits, is investigated. Consistency in lagoon status evaluation from multiple and different variables was estimated, through a case study comparing three adjacent yet contrasting French... |
Tipo: Text |
Palavras-chave: Coastal lagoon; Ecological assessment; Ecotoxicology; Eutrophication; Indicator; Management; Mediterranean Sea; Observatory. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00056/16702/14202.pdf |
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Merceron, Michel. |
The yearly study of Ulva in Brittany aims at building a time series of its proliferations and corresponding nutrient loadings. The goal is to detect results of wilful loading reductions, and to distinguish them from natural variations. This first actually quantified study is the starting bench-mark of the process. Forty-five concerned sites were listed in 1997. They are nearly the same as in 1988, 1991 and 1994 (previous rough census). The Côtes d'Armor and then the Finistère are the most affected departments. The Morbihan is less and file et Vilaine not at all. Ulva biomass was precisely quantified in about fifteen locations during the growing season, along with nitrogen loadings of local streams (mostly nitrate). The fluxes of nitrogen - the limiting... |
Tipo: Text |
Palavras-chave: Bretagne; Nitrate; Prolifération; Ulve; Eutrophisation; Brittany; Nitrate; Proliferation; Ulva; Eutrophication. |
Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/1998/rapport-1580.pdf |
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Lefebvre, A; Guelorget, O; Perthuisot, Jp; Dafir, Je. |
The biogeological evolution of Nador lagoon over the 1982-1993 period was surveyed through water parameters, chlorophyll biomass, macrobenthos and surficial sediments. Comparison of present data with the 1982-83 ones (Guelorget et al., 1984) shows that: the general organization and functioning of the basin (water circulation, biological and sedimentological zonations) remain roughly the same, the global confinement as described by the biological zonation has slightly increased, with an extension of the high confinement zones (zones IV to VI) to the detriment of the low confinement zones, notably zones I and II, the main change has been eutrophication and a dramatic increase elf organic matter inputs and sedimentation, due to increasing urbanization and the... |
Tipo: Text |
Palavras-chave: Paralic; Confinement; Morocco; Present; Eutrophication. |
Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00093/20404/18071.pdf |
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Ait Ballagh, Fatima Ezzahra; Rabouille, Christophe; Andrieux Loyer, Francoise; Soetaert, Karline; Elkalay, Khalid; Khalil, Karima. |
Sediments play an important role in dissolved inorganic phosphorus (DIP) recycling, which needs to be precisely quantified in eutrophic estuaries. A coupled field data and diagenetic modelling approach was used to study P dynamics in two estuaries (Elorn and Aulne, Brittany, France). An existing model (OMEXDIA) was extended with phosphorus (P) benthic cycle by adding dissolved inorganic phosphorus (DIP) and particulate P fractions (organic P, Fe-bound P and Ca-bound P). The model was fitted to pore water oxygen, nitrate, ammonium, oxygen demand units (reduced substances that were produced by the anoxic mineralization; Fe2+, Mn2+ and H2S; ODU), DIP, sediment organic P and C, Fe-bound P and Ca-bound P data from four seasons (February, May, July and October... |
Tipo: Text |
Palavras-chave: Phosphorus; Estuarine sediments; Eutrophication; Diagenetic modelling; Fe-bound P formation-release; Ca-bound P precipitation. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00598/71041/73089.pdf |
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Bonsdorff, E; Blomqvist, Em; Mattila, J; Norkko, A. |
The coastal and archipelago waters of the northern Baltic Sea are influenced by increasing eutrophication (significantly increasing temporal trends in nutrient availability). Increased nutrient levels and pelagic primary production have led to decreased transparency in the water body, increased plankton biomass, and increased amounts of filamentous algae. Large-scale and long-term (15-30 years) comparisons have shown that zoobenthic communities have changed significantly (altered species diversity, increased total abundance and increased biomass). The stress in the ecosystem is also illustrated at the population level (Macoma balthica). An increasing trend is shown for a near-shore fish community, where the increase in biomass has been linear over the past... |
Tipo: Text |
Palavras-chave: Baltic Sea; Eutrophication; Long-term changes; Nutrient; Zoobenthos. |
Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00093/20402/18069.pdf |
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Lison De Loma, Thierry; Harmelin-vivien, Mireille; Naim, Odile; Fontaine, Marie France. |
There has, as yet, been little study of nutrient disturbance and its consequences on the functional biology of primary consumers in coral reefs. The processing of epilithic algal communities by the damselfish Stegastes nigricans was investigated at La Reunion, at two sites of a fringing reef, oligotrophic for one and eutrophic for the other. Differences between sites were analyzed in quantifying organic matter, organic carbon, nitrogen, and organic 'nutrients' (carbohydrate, lipid and protein) in the algal food, the digestive contents and the faeces of S. nigricans. In the disturbed site, algal turfs and digestive contents presented significantly higher organic matter, organic carbon, nitrogen and organic nutrient values. Absorption efficiency of total... |
Tipo: Text |
Palavras-chave: Régime herbivore; Stegastes; Récif corallien; Eutrophisation; La Réunion; Herbivory; Stegastes; Coral reef; Eutrophication; La Reunion. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00323/43376/42835.pdf |
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Lemonnier, Hugues; Herbland, Alain; Salery, Lucas; Soulard, Benoit. |
The "Summer Syndrome", a septicemic vibriosis caused by Vibrio nigripulchritudo, is responsible for one of the two main seasonal mortalities which affect shrimp aquaculture in New Caledonia. It was identified for the first time in December 1997 in an intensive shrimp farm (called farm DF) and has been enzootic ever since. The "Summer syndrome" affects shrimp during warm-season growout. Although the geographic area concerned is limited, it is a potential threat for the industry in that the disease could spread. Analysis of grow out data from 1991 to 2002 in this farm was carried out in order to characterize the disease and the environmental conditions in relation to mortality. Results of farm DF were compared to data from farms not affected by the disease... |
Tipo: Text |
Palavras-chave: Eutrophication; Pond management; Vibriosis; Shrimp culture ponds. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1868.pdf |
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Lefebvre, Alain; Devreker, David. |
The first quantitative and comprehensive assessment of the eutrophication status from coastal to offshore French waters was performed within the Marine Strategy Framework Directive (MSFD descriptor 5) for the English Channel, the southern bight of the North Sea, the Celtic Seas, the Bay of Biscay and the Western Mediterranean Sea. Based on a combination of different data sources (in situ, satellite, and modeling products), a fully-integrated dataset was generated over the period 2010–2016. Using the best available knowledge on the eutrophication process and definition, the assessment procedure was implemented considering nutrient pressures, and direct and indirect effects of excessive inputs. The different steps of the assessment were: (i) Establishment of... |
Tipo: Text |
Palavras-chave: Eutrophication; Assessment; Marine Strategy Framework Directive (MSFD); Water Framework Directive (WFD); Oslo and Paris Convention (OSPAR); English Channel; Celtic Seas; Bay of Biscay; Mediterranean Sea; Nutrients; Chlorophyll; Oxygen; Turbidity; Phytoplankton; Macro-algae. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00641/75350/76083.pdf |
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Desmit, X.; Thieu, V.; Billen, G.; Campuzano, F.; Duliere, V.; Garnier, J.; Lassaletta, L.; Menesguen, Alain; Neves, R.; Pinto, L.; Silvestre, M.; Sobrinho, J. L.; Lacroix, G.. |
Marine eutrophication in the North-East Atlantic (NEA) strongly relies on nutrient enrichment at the river outlets, which is linked to human activities and land use in the watersheds. The question is whether human society can reduce its nutrient emissions by changing land use without compromising food security. A new version of Riverstrahler model (pyNuts-Riverstrahler) was designed to estimate the point and diffuse nutrient emissions (N, P, Si) to the rivers depending on land use in the watersheds across a large domain (Western Europe agro-food systems, waste water treatment). The loads from the river model have been used as inputs to three marine ecological models (PCOMS, ECO-MARS3D, MIRO&CO) covering together a large part of the NEA from the Iberian... |
Tipo: Text |
Palavras-chave: North-East Atlantic; Eutrophication; Model scenarios; Land-sea continuum; Land use; Pristine; Management support. |
Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00438/55007/56426.pdf |
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Lemonnier, Hugues; Hochard, Sebastien; Nakagawa, Kento; Courties, Claude; Rodier, Martine. |
We conducted a mesocosm study to investigate the combined effect of organic enrichment and sediment resuspension by shrimp on phytoplankton communities in shrimp aquaculture ponds. Hence, the factorial design included two factors, i.e., (i) shrimp density with a concomitant increase of feed input resulting in organic enrichment and (ii) with/without access of shrimp to the sediments. Increasing feed input in the system raised the eutrophication state of the environment characterized by an increase in phytoplankton biomass. Bioturbation enhanced (i) mineralization of organic matter via the microbial loop, resulting in faster nutrient recycling, (ii) an increase of primary production, and (iii) buffering capacity against eutrophication consequences. The... |
Tipo: Text |
Palavras-chave: Aquaculture; Litopenaeus stylirostris; Phytoplankton communities; Eutrophication; Bioturbation. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00392/50364/51066.pdf |
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Registros recuperados: 154 | |
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