000046929 001__ 46929
000046929 005__ 20210121082904.0
000046929 0247_ $$2doi$$a10.5194/cp-11-1249-2015
000046929 0248_ $$2sideral$$a92232
000046929 037__ $$aART-2015-92232
000046929 041__ $$aeng
000046929 100__ $$aBordiga, M.
000046929 245__ $$aMicrofossil evidence for trophic changes during the Eocene-Oligocene transition in the South Atlantic (ODP Site 1263, Walvis Ridge)
000046929 260__ $$c2015
000046929 5060_ $$aAccess copy available to the general public$$fUnrestricted
000046929 5203_ $$aThe biotic response of calcareous nannoplankton to environmental and climatic changes during the Eocene-Oligocene transition was investigated at a high resolution at Ocean Drilling Program (ODP) Site 1263 (Walvis Ridge, southeast Atlantic Ocean) and compared with a lower-resolution benthic foraminiferal record. During this time interval, global climate, which had been warm under high levels of atmospheric CO2 (pCO2) during the Eocene, transitioned into the cooler climate of the Oligocene, at overall lower pCO2. At Site 1263, the absolute nannofossil abundance (coccoliths per gram of sediment//N g-1) and the mean coccolith size decreased distinctly after the E-O boundary (EOB//33.89 Ma), mainly due to a sharp decline in abundance of large-sized Reticulofenestra and Dictyococcites, occurring within a time span of ~ 47 kyr. Carbonate dissolution did not vary much across the EOB//thus, the decrease in abundance and size of nannofossils may reflect an overall decrease in their export production, which could have led to variations in the food availability for benthic foraminifers. The benthic foraminiferal assemblage data are consistent with a global decline in abundance of rectilinear species with complex apertures in the latest Eocene (~ 34.5 Ma), potentially reflecting changes in the food source, i.e., phytoplankton. This was followed by a transient increased abundance of species indicative of seasonal delivery of food to the sea floor (Epistominella spp.//~ 33.9-33.4 Ma), with a short peak in overall food delivery at the EOB (buliminid taxa//~ 33.8 Ma). Increased abundance of Nuttallides umbonifera (at ~ 33.3 Ma) indicates the presence of more corrosive bottom waters and possibly the combined arrival of less food at the sea floor after the second step of cooling (Step 2). The most important changes in the calcareous nannofossil and benthic communities occurred ~ 120 kyr after the EOB. There was no major change in nannofossil abundance or assemblage composition at Site 1263 after Step 2 although benthic foraminifera indicate more corrosive bottom waters during this time. During the onset of latest-Eocene-earliest-Oligocene climate change, marine phytoplankton thus showed high sensitivity to fast-changing conditions as well as to a possibly enhanced, pulsed nutrient supply and to the crossing of a climatic threshold (e.g., pCO2 decline, high-latitude cooling and changes in ocean circulation).
000046929 536__ $$9info:eu-repo/grantAgreement/ES/MINECO/BES-2012-058945$$9info:eu-repo/grantAgreement/ES/MINECO-FEDER/CGL2011-23077
000046929 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttp://creativecommons.org/licenses/by/3.0/es/
000046929 590__ $$a3.638$$b2015
000046929 591__ $$aMETEOROLOGY & ATMOSPHERIC SCIENCES$$b13 / 84 = 0.155$$c2015$$dQ1$$eT1
000046929 591__ $$aGEOSCIENCES, MULTIDISCIPLINARY$$b19 / 184 = 0.103$$c2015$$dQ1$$eT1
000046929 592__ $$a2.709$$b2015
000046929 593__ $$aGlobal and Planetary Change$$c2015$$dQ1
000046929 593__ $$aStratigraphy$$c2015$$dQ1
000046929 593__ $$aPaleontology$$c2015$$dQ1
000046929 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000046929 700__ $$aHenderiks, J.
000046929 700__ $$aTori, F.
000046929 700__ $$aMonechi, S.
000046929 700__ $$0(orcid)0000-0003-0632-2548$$aFenero, R.
000046929 700__ $$0(orcid)0000-0001-9027-7772$$aLegarda-Lisarri, A.$$uUniversidad de Zaragoza
000046929 700__ $$aThomas, E.
000046929 7102_ $$12000$$2655$$aUniversidad de Zaragoza$$bDpto. Ciencias de la Tierra$$cÁrea Paleontología
000046929 773__ $$g11, 9 (2015), 1249-1270$$pClim. past.$$tClimate of the Past$$x1814-9324
000046929 8564_ $$s4519068$$uhttps://zaguan.unizar.es/record/46929/files/texto_completo.pdf$$yVersión publicada
000046929 8564_ $$s111400$$uhttps://zaguan.unizar.es/record/46929/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000046929 909CO $$ooai:zaguan.unizar.es:46929$$particulos$$pdriver
000046929 951__ $$a2021-01-21-08:17:36
000046929 980__ $$aARTICLE