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A data assimilating model for estimating Southern Ocean biogeochemistry ArchiMer
Verdy, A.; Mazloff, M. R..
A Biogeochemical Southern Ocean State Estimate (B-SOSE) is introduced that includes carbon and oxygen fields as well as nutrient cycles. The state estimate is constrained with observations while maintaining closed budgets and obeying dynamical and thermodynamic balances. Observations from profiling floats, shipboard data, underway measurements, and satellites are used for assimilation. The years 2008-2012 are chosen due to the relative abundance of oxygen observations from Argo floats during this time. The skill of the state estimate at fitting the data is assessed. The agreement is best for fields that are constrained with the most observations, such as surface pCO(2) in Drake Passage (44% of the variance captured) and oxygen profiles (over 60% of the...
Tipo: Text Palavras-chave: Southern Ocean; State estimation; Biogeochemistry.
Ano: 2017 URL: https://archimer.ifremer.fr/doc/00662/77394/78995.pdf
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A laboratory model system for analysing microbial interactions occurring in anoxic estuarine sediments. ArchiMer
Herbert, R; Keith, S.
Defined mixed populations of Clostridium butyricum, Desulfovibrio desulfuricans and Chromatium vinosum co-existed for long periods when grown in a single stage chemostat with glucose as sole carbon source. The nature and availability of the inorganic nitrogen source exerted a major effect on carbon flow in the experimental system. The data show that both the C. butyricum and D. desulfuricans isolates can utilise NO sub(3) as an e super(-)acceptor with an increase in cell yield. Under these growth conditions the free S super(2-) levels were lower resulting in more stable mixed populations. In addition the data show that the C. butyricum produces more oxidised fermentation end-products (acetate) when NO sub(3) super(-) was available and more reduced products...
Tipo: Text Palavras-chave: Chromatium vinosum; Desulfovibrio desulfuricans; Clostridium butyricum; Biogeochemistry; Models; Bacteria; Detritus; Mineralization; Anoxic sediments; Estuarine sedimentation; Analytical techniques; Carbon cycle; Interspecific relationships; Microbiology.
Ano: 1984 URL: http://archimer.ifremer.fr/doc/1984/acte-947.pdf
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Advancing Observation of Ocean Biogeochemistry, Biology, and Ecosystems With Cost-Effective in situ Sensing Technologies ArchiMer
Wang, Zhaohui Aleck; Moustahfid, Hassan; Mueller, Amy V.; Michel, Anna Pm; Mowlem, Matthew; Glazer, Brian T.; Mooney, T. Aran; Michaels, William; Mcquillan, Jonathan S.; Robidart, Julie C.; Churchill, James; Sourisseau, Marc; Daniel, Anne; Schaap, Allison; Monk, Sam; Friedman, Kim; Brehmer, Patrice.
Advancing our understanding of ocean biogeochemistry, biology, and ecosystems relies on the ability to make observations both in the ocean and at the critical boundaries between the ocean and other earth systems at relevant spatial and temporal scales. After decades of advancement in ocean observing technologies, one of the key remaining challenges is how to cost-effectively make measurements at the increased resolution necessary for illuminating complex system processes and rapidly evolving changes. In recent years, biogeochemical in situ sensors have been emerging that are threefold or more lower in cost than established technologies; the cost reduction for many biological in situ sensors has also been significant, although the absolute costs are still...
Tipo: Text Palavras-chave: In situ; Sensor; OceanObs; Ocean technology; EOVs; Biogeochemistry; Biology; Cost effective.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00514/62567/66921.pdf
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Agricultural impacts of hydrobiogeochemical cycling in the Amazon: is there any solution? Repositório Alice
FIGUEIREDO, R. de O.; CAK, A.; MARKEWITZ, D..
Abstract: Expansion of agriculture in the Brazilian Amazon has been driven not just by demands from traditional, rural producers, but also large agriculture and cattle producers, both of whom have put considerable pressure on remaining forests and their watersheds. Monitoring of these watersheds has been a focus of intensive study for the past 20 years and although this work has greatly increased our understanding, considerable gaps still remain in our ability to provide adequate recommendations for land management and associated public policies. In this study we present a summary of findings from these previous results. For small properties, the use of fire to prepare land for cultivation remains controversial, while in large properties, forest conversion...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Uso da Terra; Recurso Hídrico; Floresta Tropical Úmida; Desmatamento; Biogeochemistry; Deforestation; Land management; Land use change; Public policy; Water resources; Watersheds.
Ano: 2020 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1123149
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Balance de carbono y tasa de descomposición de mantillo y horizontes de fermentación de suelos forestales. Colegio de Postgraduados
Barrales Brito, Edgar.
El mantillo y horizontes de fermentación (CF) es un reservorio dinámico de carbono (C) en suelos forestales. Las metodologías que cuantifican la emisión de CO2 por la descomposición son escasas y requieren periodos largos de medición. Se requieren métodos para poder generar información de la emisión de CO2 de éstas capas orgánicas en tiempos cortos de medición. Los objetivos fueron: generar un protocolo para la medición de la emisión de CO2 por la descomposición de mantillo y CF con un respirómetro manométrico (OxiTop ®). Medir los reservorios de C de mantillo y CF de bosques con diferentes condiciones. Medir la emisión de CO2 del mantillo y CF y las tasas de descomposición con un respirómetro. Analizar las características químicas de los mantillos y...
Palavras-chave: Biogeoquímica; Emisión de CO2; Respirometría; Materia orgánica; Bosques; Biogeochemistry; CO2 emissions; Respirometry; Organic matter; Forest; Edafología; Maestría.
Ano: 2013 URL: http://hdl.handle.net/10521/2096
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BGC Argo quality control manual for particles backscattering ArchiMer
Schmechtig, Catherine; Boss, Emmanuel; Briggs, Nathan; Claustre, Herve; Dall'Olmo, Giorgio; Poteau, Antoine.
This document is the BGC-Argo quality control manual for particles backscattering. It describes the method used in real-time to apply quality control flags to particles backscattering calculated from specific sensors mounted on Argo profiling floats.
Tipo: Text Palavras-chave: Argo; Physical oceanography; In-situ marine data; Profiling floats; Bbp; Operational oceanography; Biogeochemistry.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00491/60262/63668.pdf
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Bio-Argo quality control manual for the Chlorophyll-A concentration ArchiMer
Schmechtig, Catherine; Claustre, Herve; Poteau, Antoine; D'Ortenzio, Fabrizio.
This document is the bio-Argo quality control manual for Chlorophyll A concentration. It describes the method used in real-time to apply quality control flags to Chlorophyll A concentration calculated from specific sensors mounted on Argo profiling floats.
Tipo: Text Palavras-chave: Argo; Physical oceanography; In-situ marine data; Profiling floats; Chlorophyll; Operational oceanography; Biogeochemistry.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00243/35385/60181.pdf
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Biogeochemical markers of organic matter along the Wight-Cherbourg transect (central English Channel) ArchiMer
Ismaili, Mm; Serve, L; Gadel, F; Lafite, R; Texier, H.
Three cruises on the Wight-Cherbourg transect were undertaken during the FluxManche II Programme in order to study the origin, nature and behaviour of organic matter inputs to the waters of the English Channel. Suspended particulate material (SPM) collected from surface and deep waters at each station was analysed at elemental level for Particulate Organic Carbon and Particulate Organic Nitrogen (POC, PON), at molecular level for main classes of organic compounds using Pyrolysis-Gas Chromatography coupled with Mass Spectrometry (Py-GC-MS) and for phenolic compounds, particularly lignin-derived phenols, using High Performance Liquid Chromatography (HPLC). The SPM content increases from the French (south) to the English coast (north) with the lowest values...
Tipo: Text Palavras-chave: Matière particulaire en suspension; Composés organiques; Marqueurs phénoliques; Biogéochimie; Manche; Suspended particulate matter; Organic compounds; Phenolic markers; Biogeochemistry; English Channel.
Ano: 1999 URL: http://archimer.ifremer.fr/doc/00325/43603/43922.pdf
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Caractérisation géochimique des sédiments de surface du golfe de Tunis OceanDocs
Fernex, F.; Ben Mammou, A.; Added, A.; Abdeljaoued, S.; Essonni, N..
The general current of the Gulf of Tunis are dependent of the general Mediterranean current. This last divides to the level of the Gulf of Tunis in two branches; a first connects by pass west coasts of the gulf while the second branch crosses the centre of the gulf with a NNW - SSE direction. The passage of this second branch of the general current creates a central zone characterised by a sediment relatively sandier than what surrounds it and controls the distribution of the different metallic elements that have for main origin the Oued Mejerda. The metallic elements here analyzed are the Fe, Zn, Ni, Co, Cu and Pb. Their concentrations vary respectively between 0,5. and 1,6%; 279 and 447 ppm; 39 and 67 ppm; 20 and 34 ppm; 9 and 20 and between 56 and 142...
Tipo: Journal Contribution Palavras-chave: Sediments; Biogeochemistry.
Ano: 2003 URL: http://hdl.handle.net/1834/1116
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Carbon and Nitrogen in the Lower Basin of the Paraíba do Sul River, Southeastern Brazil: element fluxes and biogeochemical processes. Repositório Alice
FIGUEIREDO, R. de O.; OVALLE, A. R. C.; REZENDE, C. E. de; MARTINELLI, L. A..
Abstract: The study was conducted in the lower basin of the Paraíba do Sul River (PSR), in which 57,000 km2 of the basin is located in the Brazilian states of São Paulo, Minas Gerais and Rio de Janeiro. We proposed to identify the main sources of C and N fluxes in the PSR waters, to evaluate biogeochemical processes in the watershed, and to estimate C and N riverine loads to the Atlantic Ocean in the context of the sugarcane plantation expansion for ethanol production. Riverine water samples were collected at seven stations along 12 months. Physicochemical and limnological parameters, as well as discharge, were measured together with organic and inorganic C and N species in the dissolved and suspended particulate material. C and N concentrations in bed...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Biogeoquímica; Cargas fluviais; Impactos antrópicos; Carbono; Nitrogênio; Agricultura; Impacto ambiental; Bacia hidrográfica; Biogeochemistry; Watershed; Agricultura; Environmental impact.
Ano: 2011 URL: http://www.alice.cnptia.embrapa.br/handle/doc/899035
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Changes in rivers inputs during the last decades significantly impacted the biogeochemistry of the eastern Mediterranean basin: a modelling study ArchiMer
Pagès, R.; Baklouti, M.; Barrier, Nicolas; Richon, C.; Dutay, J.-c.; Moutin, T..
The Mediterranean Sea (MS) is a semi-enclosed sea characterized by a zonal west-east gradient of oligotrophy, where microbial growth is controlled by phosphate availability in most situations. External inputs of nutrients including Gibraltar inputs, river inputs and atmospheric deposition are therefore of major importance for the biogeochemistry of the MS. This has long been considered to be driven mainly by nutrient exchanges at Gibraltar. However, recent studies indicate that river inputs signi cantly a ect nutrients concentrations in the Mediterranean Sea, although their resulting impact on its biogeochemistry remains poorly understood. In this study, our aim was to make good this lack by addressing the large-scale and long-term impact of variations in...
Tipo: Text Palavras-chave: Mediterranean Sea; River inputs; Coupled physical-biogeochemical model; Flexible stoichiometry model; Biogeochemistry; Nutrient.
Ano: 2020 URL: https://archimer.ifremer.fr/doc/00599/71118/69420.pdf
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Changing Biogeochemistry of the Southern Ocean and Its Ecosystem Implications ArchiMer
Henley, Sian F.; Cavan, Emma L.; Fawcett, Sarah E.; Kerr, Rodrigo; Monteiro, Thiago; Sherrell, Robert M.; Bowie, Andrew R.; Boyd, Philip W.; Barnes, David K. A.; Schloss, Irene R.; Marshall, Tanya; Flynn, Raquel; Smith, Shantelle.
The Southern Ocean plays a critical role in regulating global climate as a major sink for atmospheric carbon dioxide (CO2), and in global ocean biogeochemistry by supplying nutrients to the global thermocline, thereby influencing global primary production and carbon export. Biogeochemical processes within the Southern Ocean regulate regional primary production and biological carbon uptake, primarily through iron supply, and support ecosystem functioning over a range of spatial and temporal scales. Here, we assimilate existing knowledge and present new data to examine the biogeochemical cycles of iron, carbon and major nutrients, their key drivers and their responses to, and roles in, contemporary climate and environmental change. Projected increases in...
Tipo: Text Palavras-chave: Southern Ocean; Biogeochemistry; Primary production; Iron; Nutrients; Carbon; Ecosystem; Ocean acidification.
Ano: 2020 URL: https://archimer.ifremer.fr/doc/00676/78831/81113.pdf
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Composição isotópica de carbono e nitrogênio em solos e plantas de uma mata de galeria: efeito do gradiente topográfico. Infoteca-e
PARRON, L. M.; BUSTAMANTE, M. M. da C.; CAMARGO, P. B. de.
RESUMO: Estudos de composição isotópica de carbono e nitrogênio em solos e folhas são importantes para identificar diferenças nos processos de ciclagem biogeoquímica em ecossistemas. Nesse estudo foram determinadas as composições isitópicas de C e N em solos e folhas de 15 espécies lenhosas de uma Mata de Galeria no Distrito Federal, de acordo com o gradiente topográfico. O experimento foi realizado entre abril de 2001 e agosto de 2002; numa área de 100x100m , próxima à cabeceira da Mata de Galeria do Córrego Pitoco, na Reserva Ecológica do IBGE. Três transectos foram estabelecidos, paralelos ao córrego e separados a cada 45m, representando as comunidades: úmida (margem do córrego), intermediária e seca (borda da mata). Os valores de composição isotópica...
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) Palavras-chave: Biogeoquímica; Ciclagem de nutriente; Savana; Nutrient cyclong.; Cerrado; Floresta Tropical.; Biogeochemistry; Savannas; Tropical forests..
Ano: 2004 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/569212
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Concentrations and fractionation of carbon, iron, sulfur, nitrogen and phosphorus in mangrove sediments along an intertidal gradient (semi-arid climate, New Caledonia) ArchiMer
Deborde, Jonathan; Marchand, Cyril; Molnar, Nathalie; Della Patrona, Luc; Meziane, Tarik.
In mangrove ecosystems, strong reciprocal interactions exist between plant and substrate. Under semi-arid climate, Rhizophora spp. are usually predominant, colonizing the seashore, and Avicennia marina develops at the edge of salt-flats, which is the highest zone in the intertidal range. Along this zonation, distribution and speciation of C, Fe, S, N, and P in sediments and pore-waters were investigated. From the land-side to the sea-side of the mangrove, sediments were characterized by I/ increase in: (i) water content; (ii) TOC; (iii) mangrove-derived OM; II/ and decrease in: (i) salinity; (ii) redox; (iii) pH; (iv) solid Fe and solid P. Beneath Avicennia and Rhizophora, TS accumulated at depth, probably as a result of reduction of iron oxides and...
Tipo: Text Palavras-chave: Mangrove; Zonation; Biogeochemistry; New Caledonia.
Ano: 2015 URL: https://archimer.ifremer.fr/doc/00251/36252/34802.pdf
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Contrasting biogeochemical cycles of cobalt in the surface western Atlantic Ocean ArchiMer
Dulaquais, Gabriel; Boye, Marie; Middag, Rob; Owens, Stephanis; Puigcorbe, Viena; Buesseler, Ken; Masque, Pere; De Baar, Hein J. W.; Carton, Xavier.
Dissolved cobalt (DCo; <0.2 µm; 14 to 93 pM) and the apparent particulate cobalt (PCo; >0.2 µm; <1 to 15 pM) were determined in the upper water column (<1000 m) of the western Atlantic Ocean along the GEOTRACES-A02 section (64°N to 50°S). The lowest DCo concentrations, typical of a nutrient-type distribution were observed in surface waters of the subtropical domains. Strong linear relationships between DCo and phosphate (P) as well as meridional gradients of decreasing DCo from high latitudes were characterized and both linked to the Co biological requirement. External sources such as the Amazon and the atmospheric deposition were found to contribute significantly (>10%) to the DCo stock of the mixed layer in the equatorial and north...
Tipo: Text Palavras-chave: Cobalt; Biogeochemistry; Atlantic Ocean; Chemical Oceanography; GEOTRACES.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00241/35222/33732.pdf
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Decadal biogeochemical changes in the subtropical Indian Ocean associated with Subantarctic Mode Water ArchiMer
Alvarez, M.; Tanhua, T.; Brix, H.; Lo Monaco, C.; Metzl, N.; Mcdonagh, E. L.; Bryden, H. L..
Within the Subantarctic Mode Water (SAMW) density level, we study temporal changes in salinity, nutrients, oxygen and TTD (Transit Time Distribution) ages in the western (W) and eastern (E) subtropical gyre of the Indian Ocean (IO) from 1987 to 2002. Additionally, changes in Total Alkalinity (TA) and Dissolved Inorganic Carbon (DIC) are evaluated between 1995 and 2002. The mechanisms behind the detected changes are discussed along with the results from a hindcast model run (Community Climate System Model). The increasing salinity and decreasing oxygen trends from 1960 to 1987 reversed from 1987 to 2002 along the gyre. In the W-IO a decreasing trend in TTD ages points to a faster delivery of SAMW, thus less biogenic matter remineralization, explaining the...
Tipo: Text Palavras-chave: Indian Ocean; Subantarctic Mode Water; Biogeochemistry.
Ano: 2011 URL: https://archimer.ifremer.fr/doc/00253/36400/34942.pdf
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Dimethylsulfoniopropionate (DMSP) and dimethylsulfide (DMS) sea surface distributions simulated from a global three-dimensional ocean carbon cycle model ArchiMer
Aumont, Olivier; Belviso, Sauveur; Monfray, Patrick.
[1] A global model for surface dimethylsulfide (DMS) and particulate dimethylsulfoniopropionate (DMSP) (pDMS) distributions is presented. The main goals of this work were to be able to predict the regional distribution of the air-sea fluxes of DMS and to predict eventually their future evolution with climate change. Diagnostic relationships have been established from data sets obtained during the ALBATROSS and EUMELI cruises carried out in the Atlantic Ocean. These equations nonlinearly relate DMS and pDMSP concentrations to chlorophyll concentrations and to the trophic status of surface waters. This model has been embedded in the global ocean carbon cycle model Institut Pierre et Simon Laplace-Ocean Carbon Cycle Model version 2 (ISPL-OCCM2), a simple...
Tipo: Text Palavras-chave: Ocean; Biogeochemistry; Ecosystem modeling; DMS; Global.
Ano: 2002 URL: https://archimer.ifremer.fr/doc/00223/33448/31824.pdf
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Dynamique du carbone et des nutriments dans la zone côtière Baie de l’Aiguillon-Pertuis Breton et influence des apports terrestres du bassin versant du Marais poitevin ArchiMer
Lannuzel, Reva.
Coastal zones represent key systems in biogeochemical cycle couplings between continents, oceans and the atmosphere transporting considerable amounts of matter, energy and nutrients (C, N, P et Si) from land to sea. Despite its relatively modest surface area (7 % of the global ocean surface), this zone accounts for 14–30 % of all oceanic primary production. The present study deals with nutrients and carbon dynamics during a full hydrologic cycle in 2017 over the terrestrial-aquatic continuum formed by the Poitevin Marsh-Aiguillon Bay- Breton Sound to better understand terrestrial export influence on the coastal zone. Carbon and nutrient concentrations were sampled twice a month over heterogeneous sites (estuaries, channels and coastal sites) to integrate...
Tipo: Text Palavras-chave: Zone côtière; Biogéochimie; Carbone; Nutriments; Chlorophylle a; Limitation potentielle et réelle; Dynamique.; Coastal zone; Biogeochemistry; Carbon; Nutrients; Chlorophyll a; Real and potential limitation; Spatio-temporal dynamic..
Ano: 2018 URL: http://archimer.ifremer.fr/doc/00445/55647/57299.pdf
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Estimates of carbon flow through bacteriplankton in the S. Benguela upwelling region based on 3H-thymidine incorporation and predator-free incubations. ArchiMer
Lucas, M; Painting, S; Muir, D.
Spatial and temporal estimates of bacterial numbers, biomass, activity and production were measured in the S. Benguela upwelling system during the course of a phytoplankton bloom. Bacterial numbers and biomass were highest in the euphotic zone and correlated closely with particulate carbon in the water column rather than with chlorophyll a concentrations. 3H-Thymidine incorporation gave good estimates of production. Differential utilisation of photosynthetic exudates and detrital POC by bacterioplankton during the course of a bloom might account for the varying significance ascribed to exudates and POC as a source of carbon for bacterial production.
Tipo: Text Palavras-chave: Ecological associations; Algal blooms; Biomass; Microorganisms; Carbon cycle; Bacteria; Nannoplankton; Upwelling; Biogeochemistry.
Ano: 1984 URL: http://archimer.ifremer.fr/doc/1984/acte-985.pdf
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Evaluation of the heterotrophic activity in waters by microanalytical methods. ArchiMer
Bertoni, R.
The radiochemical methods proposed for evaluating heterotrophic activity in waters have been severely criticized in recent years because they are not considered to be sufficiently realistic. Thus, the possibility of directly measuring the heterotrophic consumption of naturally occurring Organic Carbon (OC) in fresh water samples incubated under controlled conditions has been evaluated. The analytical performances of two OC analyzers utilizable for this purpose are discussed here, and some examples of the results obtained by the direct measurement of OC consumption are presented. The consumption rates thus measured ranged from 11.6 to 50.2 mu gC/ 1.h. Although the technique discussed here is less sensitive than radiochemical methods, the few assumptions...
Tipo: Text Palavras-chave: Biogeochemistry; Microbiology; Carbon cycle; Organic carbon; Water; Heterotrophic organisms; Analytical techniques.
Ano: 1984 URL: http://archimer.ifremer.fr/doc/1984/acte-950.pdf
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