Seasonal Pattern of the Biogeochemical Properties of Mangrove Sediments Receiving Shrimp Farm Effluents (New Caledonia) Auteur(s) : Marchand, Cyril Molnar, N. Deborde, Jonathan Della Patrona, Luc Meziane, Tarik Éditeur(s) : OMICS Publishing Group Résumé : Coastal tropical shrimp farming may impact the adjacent ecosystems through the release of large quantities of effluents rich in nutrients. In New Caledonia, mangroves are considered as a natural biofilter to reduce impacts on the surrounding World Heritage listed lagoon. Our main objective was to understand the influence of effluent discharge on the biogeochemistry of mangrove sediments. A monitoring of the physico-chemical parameters of mangrove sediments was carried out during a whole year, including active and non active periods of the farm. The parameters studied were: i) benthic primary production (Chl-a concentrations), ii) physico-chemical parameters of sediments (redox potential, pH, salinity, TOC, TN, TS, δ13C and δ15N), iii) concentrations of dissolved nitrogen, iron and phosphorus. A mangrove developing in the same physiographic conditions, presenting the same zonation, and free of anthropogenic input was used as reference. The concentration of benthic Chl-a measured at sediment surface in the effluent receiving mangrove was twice to three times that measured in the control zone whatever the season. We thus suggest that nutrients inputs significantly increased the phytobenthic production in the effluent receiving mangrove during the whole year, even after the cessation of discharges and because of natural seasonal dynamic of phytobenthos. Although the flow of surface OM was increased, the OM content at depth was not higher than in the control mangrove. However, the contribution of mangrove detritus to the sedimentary organic pool was higher probably as a result of higher density and much greater individual size of the mangrove trees. Unlike the control mangrove sediment, the effluent receiving mangrove sediment was not stratified, redox potential values were high and presence of Fe3+ was detected down to 50 cm depth, probably as a result of a larger root system, allowing a better sediment oxygenation and accentuated OM decomposition processes, and thus limiting ecosystem saturation. Journal of Aquaculture Research & Development (21559546) (OMICS Publishing Group), 2014-07-03 , Vol. 5 , N. 5 , P. 1-13 Droits : 2014 Marchand C, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. http://archimer.ifremer.fr/doc/00251/36253/34801.pdf DOI:10.4172/2155-9546.1000262 http://archimer.ifremer.fr/doc/00251/36253/ | Partager |
High rate algal pond treatment for water reuse in a marine fish recirculation system: Water purification and fish health Auteur(s) : Metaxa, Elisabeta Deviller, Genevieve Pagand, P Alliaume, C Casellas, C Blancheton, Jean-paul Éditeur(s) : Elsevier Résumé : Regardless of the degree of closure of a recirculation system, effluents are produced and replacement water is needed, which limits the possibility of locating a seawater production system away from the shoreline. At the Palavas Ifremer station, in the south of France, a High Rate Algal Pond (HRAP) was operated during several years to treat the effluent from a recirculating aquaculture system before reusing it. The effect of the HRAP-treated water on the recirculation system and on the fish was investigated and the optimal algae growing conditions were defined. The experiments were carried out in three rearing systems: one flow through, one recirculating and one recirculating with a HRAP. The water flow rate, temperature, pH and salinity conditions were similar in all systems. The effect of reusing the HRAP-treated water is very limited (1) on the functioning of the recirculation system and (2) on fish performance, but it allows a significant reduction of the dissolved inorganic nitrogen and phosphorus concentration in the rearing water. HRAP treatment reduced metal accumulation in muscle and liver of RAS fish, except for chromium and arsenic. All biomarkers presented no significant difference between systems, except for Superoxide Dismutase (SOD) and EROD, which showed a higher concentration in RAS and in both recirculating system respectively. (c) 2005 Elsevier B.V. All rights reserved. Aquaculture (0044-8486) (Elsevier), 2006-03 , Vol. 252 , N. 1 , P. 92-101 Droits : 2005 Elsevier http://archimer.ifremer.fr/doc/2006/publication-2306.pdf DOI:10.1016/j.aquaculture.2005.11.053 http://archimer.ifremer.fr/doc/00000/2306/ | Partager Voir aussi Fish health High rate algal pond Macroalgae Aquaculture effluent Recirculation aquaculture systems Télécharger |
Effect of water exchange on effluent and sediment characteristics and on partial nitrogen budget in semi-intensive shrimp ponds in New Caledonia Auteur(s) : Lemonnier, Hugues Faninoz, Sebastien Éditeur(s) : Blackwell science Résumé : An experiment was conducted in six earthen ponds with 20 shrimps m(-2) Litopenaeus stylirostris (Stimpson) during the warm season in New Caledonia to study the dynamics of wastes in relation with water exchange rate (WER). The nitrogen budget was established, taking into account the different forms of nitrogen in the water, sediment, feed and shrimp. Data from a wide range of treatments applied in unreplicated ponds were treated using regression analysis to establish the relationship between WER and partial nitrogen budget, sediment characteristics and shrimp performance. To compare effluent quality between treatments during the season, data were analysed using the non-parametric sign test. The water outflow was characterized by a decrease in the concentrations of N-mineral forms (TAN, NO2--NO3-), an increase in the concentration of organic soluble and sestonic organic forms (expressed in terms of particulate nitrogen, particulate organic carbon, chlorophyll a) compared with the water inflow. Increasing WER increased the amount of exported wastes and mainly in the organic forms and TAN can be considered as negligible. The nitrogen budget showed that 19-46% of nitrogen input (feed+water) was exported into the coastal environment. The results showed that the quality of the sediment decreased as WER decreased. The potential negative impact of the developing industry in New Caledonia on the costal environment could be partially reduced in a first step by decreasing WER. However, if applied in the farms, this practice should be linked to a close survey of the evolution of sediment quality. Aquaculture Research (1355-557X) (Blackwell science), 2006-06 , Vol. 37 , N. 9 , P. 938-948 Droits : 2006 Blackwell Publishing, Inc. http://archimer.ifremer.fr/doc/2006/publication-1811.pdf DOI:10.1111/j.1365-2109.2006.01515.x http://archimer.ifremer.fr/doc/00000/1811/ | Partager |
Spatial and temporal extension of eutrophication associated with shrimp farm wastewater discharges in the New Caledonia lagoon Auteur(s) : Thomas, Yoann Courties, Claude El Helwe, Yasmin Herbland, Alain Lemonnier, Hugues Éditeur(s) : Pergamon-elsevier Science Ltd Résumé : Shrimp farming in New Caledonia typically uses a flow-through system with water exchange rates as a tool to maintain optimum hydrological and biological parameters for the crop. Moreover, the effluent shows hydrobiological characteristics (minerals, phytoplankton biomass and organic matter) significantly higher than that of the receiving environment. Separate surveys were carried out in a bay (CH Bay) with a medium-size intensive farm (30 ha) (PO) and in a mangrove-lined creek (TE Creek) near a larger semi-intensive farm (133 ha) (SO). Net loads of nitrogen exported from the semi-intensive farm and the intensive farm amounted to 0.68 and 1.36 kg ha(-1) day(-1), respectively. At CH Bay, discharge effects were spatially limited and clearly restricted to periods of effluent release. The high residence time at site TE favoured the installation of a feedback system in which organic matter was not exported. Mineralization of organic matter led to the release of nutrients, which in turn, caused in an increased eutrophication of this ecosystem. The study of the pico- and nanophytoplankton assemblages showed (i) a shift in composition from picophytoplankton to nanophytoplankton from offshore towards the coast and (ii) a shift within the picophytoplankton with the disappearance of Prochlorococcus and the increase of picoeucaryotes towards the shoreline. These community changes may partially be related to a nitrogen enrichment of the environment by shrimp farm discharges. Thus, in view of the recent addition of the New Caledonian lagoon to the UNESCO World Heritage list, the data presented here could be a first approach to quantify farm discharges and evaluate their impact on the lagoon. (C) 2010 Elsevier Ltd. All rights reserved. Marine Pollution Bulletin (0025-326X) (Pergamon-elsevier Science Ltd), 2010 , Vol. 61 , N. 7-12 , P. 387-398 Droits : 2010 Elsevier Ltd All rights reserved. http://archimer.ifremer.fr/doc/00014/12527/9882.pdf DOI:10.1016/j.marpolbul.2010.07.005 http://archimer.ifremer.fr/doc/00014/12527/ | Partager |
Effluents from land based marine farms: nature, treatment, valorisation, modelisation. Applications to fish and shrimp rearing Auteur(s) : Hussenot, Jerome Lefebvre, Sebastien Martin, Jean-louis Éditeur(s) : Man and Coastal Areas – Towards a sustainable Aquaculture, May 2000 Résumé : Fish culture (seabass, turbot...) on the French metropolitan coast, and shrimp culture in the overseas territories (essentially New Caledonia and Tahiti) are subject to a regular development through land based farms. Three thematic of research on aquaculture ponds are carried out in CREMA-L’Houmeau, in collaboration with producers. The aim of the first one is to determine the optimal rearing conditions (stocking density, water renewal rate, input of oxygen, rate of feeding...) which allow to minimise the quantity of wastes for a similar final biomass. The second part aims to reduce the nutrient loading in the effluent, through open-air treatments: sedimentation ponds, foam fractionation, mass production of phytoplankton, and rearing of molluscs on the produced phytoplankton. The third part concerns research aiming to model the “ production - treatment - valorisation ” relationships. Droits : 2000 Ifremer http://archimer.ifremer.fr/doc/00016/12728/9650.pdf http://archimer.ifremer.fr/doc/00016/12728/ | Partager |
Planktonic ecosystems in the channel - trophic relations Auteur(s) : Lehoerff, Genevieve Erard-le Denn, Evelyne Arzul, Genevieve Éditeur(s) : Gauthier-Villars Résumé : Four planktonic coastal ecosystems from the western Channel to the southern part of the North Sea have been compared. The characteristics of the south of the North Sea are a very high planktonic biomass with an annual maximum value of 45 mg C m-3 h-1 for primary production, a maximum of 11 mg m-3 for Chlorophyll a and 60 mg C m-3 for zooplanktonic biomass (expressed in term of carbon weight), linked with an oscillating ecosystem. In the western Channel primary production shows an annual maximum value of 8 mg C m-3 h-1, die chlorophyll a, a maximum of 2.5 mg m-3 and zooplanktonic carbon weight of 14 mg C m-3 linked to a greater inertia in the system. Turnover is faster in the north. Trophic efficiency ratios have been calculated and linked to hydrodynamic conditions and currents. The impacts of a thermal perturbation from a nuclear power plant effluent (DT 11-degrees - 15-degrees-C) applied to ecosystems are compared. Oceanologica Acta (0399-1784) (Gauthier-Villars), 1993 , Vol. 16 , N. 5-6 , P. 661-670 Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00100/21130/18750.pdf http://archimer.ifremer.fr/doc/00100/21130/ | Partager |
Guide méthodologique pour l'élaboration des dossiers de demande d'autorisation d'Installations Classées pour la Protection de l'Environnement (ICPE) en matière de pisciculture marine pour la région Corse Auteur(s) : Roque D'Orbcastel, Emmanuelle Sauzade, Didier Ravoux, Georges Coves, Denis Résumé : Sea fish farms with production of more than 20 tons per year in France must obtain two operating licences: (i) one for Sea Farming (AECM), with the aim of ensuring that the granted site and use of the maritime public domain for exploitation will respect all restrictions of general interest; (ii) one for regulating Facilities Classified for the Protection of the Environment (ICPE). Although the first one requires a relatively simple licence request file, the second one demands a very complete file, which includes, beyond the notice of exploitation information, a complete impact study, as well as a hazards study and a health and safety notice. In this context, petitioners in Corsica (adjustment of status or new exploitation) are faced with the same difficulties, which highlighted the need for a methodological guide adapted to each region's specific situation, assembling in particular the necessary baseline data (legal, zootechnical, geographical, climatic, socio-economic, ecological...) as well as recognised methods for evaluating the potential effects of the farm on the environment.
Development of this guide was supported by ADEC and supervised by a steering committee composed of representatives from the administrations concerned, fish farmers and scientific bodies. The significant aspects dealt with the effects of fish farming on Posidonie herbarium, a protected species very present in Corsica and with coordinating the two AECM and ICPE procedures.
For each part of the ICPE file, the guide introduces the technical or scientific context and, depending upon the case, the state of the art, sources of available data, acquisition and methods of acquiring measurements and of assessing the potential effects, as well as practical editing recommendations.
Finally, the guide is made complete by a model schedule of conditions designed to help petitioners to have a specialist research department incorporate all or part of the file.
This guide primarily concerns first-time marine facilities for exploitation in Corsica, conceived of as in the open sea rather than in confined spaces. Nonetheless, any fish farmer or future fish farmer needing to process a request for an exploitation licence may find it useful.
Les piscicultures marines de plus de 20 t/an de production sont soumises en France à l'obtention de deux autorisations d'exploiter : (i) celle au titre des Cultures Marines (AECM), visant à s'assurer que le site concédé et l'usage du domaine public maritime pour l'exploitation permettent de respecter l'ensemble des contraintes d'intérêt général ; (ii) celle au titre de la réglementation des Installations Classées pour la Protection de l'Environnement (ICPE). Si la première nécessite un dossier de demande d'autorisation relativement simple, la seconde requiert un dossier très complet, qui comprend, outre une notice de renseignements sur l'exploitation, une étude d'impact complète, ainsi qu'une étude des dangers et une notice d'hygiène et de sécurité. Dans ce contexte, les demandeurs en Corse (régularisation ou exploitation nouvelle) sont confrontés aux mêmes difficultés, ce qui a mis en évidence le besoin d'un guide méthodologique adapté aux spécificités régionales, rassemblant en particulier les données de base nécessaires (juridiques, zootechniques, géographiques, climatiques, socio-économiques, écologiques...) ainsi que les méthodes reconnues de l'évaluation des effets potentiels de la ferme sur l'environnement. L'élaboration de ce guide a été soutenue par l'ADEC et suivie par un comité de pilotage composé de représentants des administrations concernées, des pisciculteurs et d'organismes scientifiques. Les aspects importants ont porté sur les effets de la pisciculture sur l'herbier de Posidonie, espèce protégée très présente en Corse et sur la coordination entre les deux procédures AECM et ICPE. Pour chaque partie du dossier ICPE, le guide présente le contexte technique ou scientifique et selon le cas, l'état de l'art, les sources de données disponibles, les méthodes d'acquisition des mesures et d'évaluation des effets potentiels, ainsi que des recommandations pratiques de rédaction. Enfin, le guide est complété par un cahier des charges type destiné à aider les demandeurs à confier à un bureau d'étude spécialisé la réalisation de tout ou partie de la constitution du dossier. Ce guide concerne prioritairement les installations marines de nouvelles exploitations en Corse, envisagées en mer ouverte plutôt que dans des espaces confinés. Néanmoins tout pisciculteur ou futur pisciculteur devant instruire une demande d'autorisation d'exploiter peut y trouver intérêt. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/2004/rapport-2188.pdf http://archimer.ifremer.fr/doc/00000/2188/ | Partager |