|
|
|
| Registros recuperados: 21 | |
|
|
| Fontanier, Christophe; Mamo, Briony; Toucanne, Samuel; Bayon, Germain; Schmidt, Sabine; Deflandre, Bruno; Dennielou, Bernard; Jouet, Gwenael; Garnier, Eline; Sakai, Saburo; Lamas, Ruth Martinez; Duros, Pauline; Toyofuku, Takashi; Sale, Aurelien; Belleney, Deborah; Bichon, Sabrina; Boissier, Audrey; Cheron, Sandrine; Pitel, Mathilde; Roubi, Angelique; Rovere, Mickael; Gremare, Antoine; Dupre, Stephanie; Jorry, Stephan. |
| In this short communication, we present a multidisciplinaty study of sedimentary records collected from a deep-sea interfluve proximal to the mouths of major northwestern Madagascan rivers. For the last 60 years, the seafloor has been repeatedly disturbed by the deposition of organic rich, tropical, terrestrial sediments causing marked reductions in benthic biodiversity. Increased soil erosion due to local land-use, deforestation and intensifying tropical cyclones are potential causes for this sedimentary budget and biodiversity shift. Our marine sedimentary records indicate that until now, these conditions have not occurred within the region for at least 20,000 years. |
| Tipo: Text |
Palavras-chave: Multidisciplinary study; Benthic foraminifera; Land-use; Tropical cyclones. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00413/52488/53276.pdf |
| |
|
|
| Mojtahid, Meryem; Jorissen, Frans; Durrieu, Josiane; Galgani, Francois; Howa, Helene; Redois, Fabrice; Camps, Roger. |
| We present a study of benthic foraminiferal. faunas from the outer continental shelf off Congo (tropical West Africa), with the aim to determine the impact of the discharge of oily drill cuttings on the sea floor environment, to judge the regenerating capacity of the benthic ecosystem, and to investigate the possibility to develop an environmental monitoring method for open marine continental shelf environments, based on benthic foraminifera. We studied the spatial distribution and microhabitats of living and dead foraminiferal faunas, sampled in April 2003, 4 years after the end of disposal activities, in the upper 3 cm of the sediment at 9 stations (about 180 m depth) offshore Congo, that were subject to various degrees of pollution by oily cuttings from... |
| Tipo: Text |
Palavras-chave: Oily cuttings; Opportunistic taxa; Drill mud; Bio indicator; Eutrophication; Outer shelf; Benthic foraminifera. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2170.pdf |
| |
|
| |
|
|
| Duros, Pauline; Silva Jacinto, Ricardo; Dennielou, Bernard; Schmidt, S.; Martinez Lamas, Ruth; Gautier, Emeric; Roubi, Angelique; Gayet, Nicolas. |
| Living (Rose Bengal stained) and dead benthic foraminifera were investigated at 6 deep-sea sites sampled in the Capbreton canyon area (Bay of Biscay, France). Three sites were located along the canyon axis at 301 m, 983 m and 1478 m and 3 stations were positioned on adjacent terraces at 251 m, 894 m and 1454 m. Sedimentary features indicate that frequent sedimentary disturbances of different magnitudes occur along the Capbreton canyon axis and adjacent terraces. Such environmental conditions cause the presence of very particular benthic environments. Along the 6 studied sites, different foraminiferal responses to various sedimentary patterns are observed revealing the complexity of this canyon environment. Some sites (Gitan 3 (canyon axis), Gitan 5 (canyon... |
| Tipo: Text |
Palavras-chave: Benthic foraminifera; Capbreton canyon; Habitat disturbance; Turbidite; Submarine canyon. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00360/47121/47052.pdf |
| |
|
| |
|
|
| Jorissen, F. J.; Bicchi, E.; Duchemin, G.; Durrieu, J.; Galgani, Francois; Cazes, L.; Gaultier, M.; Camps, R.. |
| In order to assess the possible environmental impact of oily cuttings discharged during oil exploration activities, we studied the benthic foraminiferal faunas in a five-station, 4-km-long sampling transect around a cuttings disposal site at about 670 m depth offshore Angola (W Africa). where drilling activities started 1.5 years before sampling. Living (Rose Bengal stained) and dead foraminiferal faunas were sampled in March 2006. The faunal patterns mirror the spatial distribution of hydrocarbons, which are dispersed into a southeastern direction. Four different areas can be distinguished on the basis of the investigated faunal parameters (density, diversity and species composition of the living fauna, and comparison with subrecent dead faunas). The... |
| Tipo: Text |
Palavras-chave: W Africa; Upper continental slope; Offshore Angola; Drill cuttings; Bio indicators; Benthic foraminifera. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-7301.pdf |
| |
|
|
| González-Regalado,María Luz; Ruiz,Francisco; Abad,Manuel; Civis,Jorge; González Delgado,José Ángel; Muñoz,Juan Manuel; García,Edith Xio Mara; Pendón,José Gabriel; Toscano,Antonio. |
| Lithostratigraphical and faunal analyses of five Pliocene sections located in the southwestern Guadalquivir Basin (S Spain) permit reveal three main facies, which represent shallow marine fairweather conditions (FA-1), storm events (FA-2) and littoral/fluvial environments (FA-3). The vertical disposition of these facies indicates a regressive sequence. The statistical study of foraminiferal populations revealed five infralittoral and circalittoral assemblages. Vertical and horizontal variations among these assemblages, the P/B ratio and four diversity indices, together with the mollusc distributions, suggest the presence of a shallow marine palaeoenvironment in this area in the Lower Pliocene, with an increasing depth towards the southwestern. The main... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Benthic foraminifera; Storms; Lower Pliocene; SW Spain. |
| Ano: 2009 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0002-70142009000200011 |
| |
|
|
| Angue Minto’o, Charlie Morelle; Bassetti, Maria-angela; Toucanne, Samuel; Jouet, Gwenael. |
| The study of Quaternary sediments covering the last 550 kyr from the borehole GDEC-4-2, East-Corsica basin, was performed through the study of benthic meiofaunal assemblages (ostracoda and benthic foraminifera) whose distribution responds to climate changes, and glacial–interglacial variability in particular. The interglacial ostracod group is mainly composed of the Argilloecia acuminata, Cytheropteron alatum, Henryhowella sp., Polycope sp. and Cytherella sp., which indicate an enhanced surface productivity and possibly high bottom water temperature during these warm intervals. Benthic foraminifera, such as Hoeglundina elegans, Sigmoilopsis schlumbergeri, Bigenerina nodosaria and Hyalinea balthica are predominant during interglacial periods and also show... |
| Tipo: Text |
Palavras-chave: Est-Corse; Ostracode; Foraminifère benthique; Groupe allochtone; East-Corsica; Ostracoda; Benthic foraminifera; Allochthonous group. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00313/42426/42030.pdf |
| |
|
| |
|
| |
|
|
| Goineau, A.; Fontanier, Christophe; Mojtahid, M.; Fanget, Anne-sophie; Bassetti, M-a.; Berne, Serge; Jorissen, F.. |
| Dead benthic foraminiferal faunas (> 150 μm) from the Rhône prodelta (Gulf of Lions, NW Mediterranean) were analysed at 41 stations (15–100 m water depth) sampled in June 2005 and September 2006, and compared to the living faunas investigated during previous studies at the same stations. The comparison between dead and living assemblages enhances the understanding of taphonomic processes that may modify the composition of the dead faunas in this area. We observed a loss of individuals from living to dead assemblages of species characterised by a fairly fragile test and therefore more prone to fragmentation or dissolution (e.g., Bolivina alata, Quinqueloculina tenuicollis). Allochthonous dead and/or live specimens may be transported to some parts of the... |
| Tipo: Text |
Palavras-chave: Benthic foraminifera; Rhone prodelta; Taphonomy; Thanatofacies; Palaeoceanography. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00273/38399/36725.pdf |
| |
|
|
| TAPIA,RAÚL; LANGE,CARINA B; MARCHANT,MARGARITA. |
| This study examines onshore-offshore and vertical distribution of living (Rose Bengal stained) benthic foraminifera (> 180 μm fraction) from three sediment stations along a bathymetric transect off Concepción, Chile (station 18 = 88 m water depth, station 26 = 120 m, station 40 = 1,030 m), within and below the oxygen minimum zone. All cores were collected in austral winter. Calcareous foraminifera dominated the three stations. The species composition, living foraminifera density, and vertical distribution patterns within the sediment changed in accordance with bottom water dissolved oxygen concentration and food availability. Onshore-offshore pattern revealed overall highest living foraminiferal densities at shelf stations 18 and 26 where... |
| Tipo: Journal article |
Palavras-chave: Benthic foraminifera; Sediments; Oxygen minimum zone; Concepción; Chile. |
| Ano: 2008 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2008000300009 |
| |
|
|
| Durand, M.; Mojtahid, M.; Maillet, G. M.; Proust, J. -n.; Lehay, D.; Ehrhold, Axel; Barre, A.; Howa, H.. |
| We used sedimentological and foraminiferal characteristics of four sedimentary cores, supported by paleogeographical and historical data, to reconstruct the depositional history of the inner Loire estuary (Near Saint-Nazaire, France) and the response of benthic foraminifera to the mid- to late-Holocene marine flooding of the incised valley. These were further used to evaluate the consequent changes in estuarine morphological and hydro-sedimentary patterns during this time period. Our results described significant changes in hydro-sedimentary dynamics over the past ~ 6 kyrs BP. At our location, these changes expressed the combined influence of marine (e.g., tide, storm waves) and fluvial dynamics (e.g., floods), which are linked, on a broader scale, to... |
| Tipo: Text |
Palavras-chave: Macrotidal estuary; Mid-latitude estuary; Holocene paleoenvironment; Estuarine facies; Benthic foraminifera; Sea-level change. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00347/45849/45511.pdf |
| |
|
|
| Lindsay, Colin M.; Lehman, Scott J.; Marchitto, Thomas M.; Carriquiry, Jose D.; Ortiz, Joseph D.. |
| Previous studies have shown that radiocarbon activities (C-14) in the low-latitude, middepth Pacific and Indian Oceans were anomalously low during Heinrich Stadial 1 (HS1, similar to 17.8-14.6ka) and the Younger Dryas (YD, similar to 12.8-11.5ka), coincident with intervals of rising atmospheric CO2 concentration and declining atmospheric C-14. However, a full explanation of these events remains elusive due to sparse and sometimes conflicting data. Here we present new C-14 measurements on benthic and planktic foraminifera that, in combination with previously published measurements, enable us to reconstruct the C-14 depth gradient near Baja California. Vertical profiles were similar to present during the Last Glacial Maximum and BOlling/Allerod (14.6-12.8ka)... |
| Tipo: Text |
Palavras-chave: Radiocarbon; Deglaciation; Heinrich Stadial 1; Baja California; Benthic foraminifera. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00496/60797/64925.pdf |
| |
|
|
| Kristjansdottir, G. B.; Lea, D. W.; Jennings, A. E.; Pak, D. K.; Belanger, C.. |
| We have developed cold-end Mg/Ca-temperature calibrations for three common Arctic benthic foraminifera, Islandiella norcrossi/helenae, Melonis barleeanus, and Cassidulina neoteretis, and compare the three calibrations in a late Holocene downcore record (0-4000 cal yr B.P.). The calibration and downcore trends for the three Arctic species extend the observation that Mg incorporation into benthic foraminifera is species specific. For the calibration we use a set of CTD casts, bottom water delta(18)O(seawater) measurements, and surface grab-samples collected from the Iceland margin (cruise B997) and the Greenland margin (cruise BS1191). Water depth of sites used ranges from 165 to 656 m, while spatial bottom temperature ranges from 0 to 7 degrees C. Mg/Ca... |
| Tipo: Text |
Palavras-chave: Mg/Ca; Benthic foraminifera; Temperature calibrations; Arctic; Shelf environment; Iceland shelf. |
| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00238/34935/33256.pdf |
| |
|
|
| Pascual, A.; Rodríguez-lázaro, J.; Martínez-garcía, B.; Varela, Z.. |
| Benthic foraminifera assemblages from a sedimentary core (PP10-12; 701 mwd) from the SE Bay of Biscay allow us to trace palaeoceanographic and palaeoclimatic changes occurred in this region during mid MIS 3 (Marine Isotope Stage 3) and MIS 1 interval (37–2.4 ka BP). Results are based on 176 benthic foraminifera species considering their ecology, the difference between autochthonous/allochthonous, preservation and oxygen rates, thus evidencing climatic and oceanographic events. MIS 3 is characterised by waters with a dominance of Cassidulina laevigata and Uvigerina peregrina. By the end of this interval, waters became colder and less oxygenated indicated by the occurrence of Melonis affinis. These conditions persisted at the beginning of MIS 2. The Heinrich... |
| Tipo: Text |
Palavras-chave: Palaeoclimatology; Palaeoceanography; Benthic foraminifera; MIS 3-MIS 1; Bay of Biscay. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00627/73910/73242.pdf |
| |
|
|
| Lambert, Clément; Vidal, Muriel; Penaud, Aurélie; Le Roy, Pascal; Goubert, Evelyne; Pailler, Yvan; Stephan, Pierre; Ehrhold, Axel. |
| Sedimentological, palynological, and micropalaeontological studies carried out throughout the first half of the Holocene, during the Mesolithic/Neolithic transition in the Bay of Brest (i.e. 9200–9000 and 6600–5300 cal. BP) and in the Bay of Douarnenez (i.e. 9200–8400 cal. BP), allowed characterizing coastal environmental changes under the increasing influence of the relative sea-level rise. The gradual flooding of the two studied sites implied a transition from river valleys to oceanic bays as revealed by the gradual retreat of salt marsh environments, as detected through palynological analysis. In addition, these high-resolution studies highlight the regional imprint of the North Atlantic millennial climate variability in north-western coastal... |
| Tipo: Text |
Palavras-chave: Benthic foraminifera; Climate variability; Dinoflagellate cysts; Human impacts; Palaeoenvironments reconstructions; Pollen grains. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00472/58341/60920.pdf |
| |
|
| |
|
| |
|
| |
| Registros recuperados: 21 | |
|
|
|
