Search results for " plank"

Productivity modes in the Mediterranean Sea during Dansgaard–Oeschger (20,000–70,000 yr ago) oscillations

2013

The study of planktonic organisms during abrupt climatic variations of the last glacial period (Dansgaard-Oeschger oscillations, D-O) may reveal important insights on climatic, oceanographic and biological interactions. Here we present planktic foraminifera and coccolithophore data collected at the Ocean Drilling Program Site 963 (Sicily Channel), with a mean sampling resolution of respectively 43.5 and 98.9. yr, over the interval between 70,000 and 20,000. yr ago. The paleoenvironmental reconstruction suggests that three different scenarios can be seen across each D-O cycle: 1. oligotrophic surface water and a deep thermocline for the early Interstadials; 2. a Deep Chlorophyll Maximum and …

Biostratigraphy and isotope stratigraphy of upper Maastrichtian–Danian marine deposits of the Kopet-Dagh Basin, northeast Iran

2018

Abstract Biostratigraphy, using foraminifera and echinoids, plus high-resolution carbon isotope stratigraphy of the upper Maastrichtian–Danian interval in the western part of the Kopet-Dagh Basin in northeast Iran are outlined. Our study of shallow-marine carbonate platform deposits of the Kalat Formation, rich in larger benthic foraminifera (predominantly Clypeorbis mammillatus Schlumberger, Lepidorbitoides sp. and Siderolites calcitrapoides Lamarck), has allowed the definition of a C. mammillatus-S. calcitrapoides Assemblage Zone, of late Maastrichtian age. Clypeorbis mammillatus is here recorded for the first time from the Maastrichtian Kalat Formation and represents the most easterly fi…

Deep-Sea Bioluminescence Blooms after Dense Water Formation at the Ocean Surface

2013

The deep ocean is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in th…

The Calabrian Stage redefined

2008

The name Calabrian was introduced in the geological literature by the French stratigrapher Maurice Gignoux in 1910, and later described in his important monograph (633 pages) "Les formations marines pliocènes et quaternaires de l'Italie du sud et de la Sicile" published in 1913. Detailed data were provided on several sections (Santa Maria di Catanzaro, Caraffa, Monasterace, Palermo) and on their fossil content. The Calabrian Stage has commonly been used for over fifty years as the oldest subdivision of the Quaternary, notably in the time scales of Berggren & van Couvering (1974) and Haq & Eysinga (1987). However, after the GSSP for the Pliocene/Pleistocene boundary (P/P) was approved by INQ…

INTEGRATED CALCAREOUS PLANKTON BIOSTRATIGRAPHY OF SELECTED MIOCENE SUCCESSIONS IN THE NORTHERN CALABRIA (ITALY).

2005

An integrated calcareous plankton biostratigraphic approach on six sections cropping out in Northern Calabria allowed to define a revised chronostratigraphic framework for Tortonian-Messinian deposits. Four sections have been investigated in the Amantea Basin (Timpone Napoli, Vallone Salina, Case Vespano, and Cozzo Salice) and two in the Rossano Basin (Vallone Casino and Cozzo Sant'Isidoro). Biostratigraphic analyses have been based on quantitative counting of planktonic foraminifers and semiquantitative counting of nannofossils. The Timpone Napoli and Vallone Salina sections are Late Tortonian in age and referable to the Globorotalia suterae Zone. In terms of nannofossils zonal scheme thes…

Nitrate uptake rates in freshwater plankton: the effect of food web structure

2008

9 pages, 3 figure, 1 table

Ten Years of Paleoceanographic Studies at ODP Site 963 (Central Mediterranean Sea)

2014

The geographical location, the shape and the circulation pattern makes the Mediterranean Sea an ideal laboratory to study the interplay between different climatic systems, abrupt climate changes and the response of marine ecosystems. The Ocean Drilling Program Site 963 was drilled in the Northwestern part of the Sicily Channel, the sill that divides the western from the eastern Mediterranean Sea. Numerous papers have been published on Site 963 sediments in the last decade, investigating Mediterranean paleoceanographic themes. Here we offer a synthetic framework of these investigations carried out by sub-centennial resolution. We present the whole sequence of suborbital climatic oscillations…

Characterization of paralytic shellfish toxins in seawater and sardines (Sardina pilchardus) during blooms of Gymnodinium catenatum

2010

Latvijas Zinātņu akadēmijas, Latvijas Universitātes Astronomijas institūta populārzinātnisks gadalaiku izdevums

2012

Contents: JĀNIS IKAUNIEKS – 100: N.Cimahoviča. Subjacent Was Venture ; I.P. Articles on Jānis Ikaunieks and Articles by Jānis Ikaunieks in Zvaigžņotā debess ; “ZVAIGŽŅOTĀ DEBESS” FORTY YEARS AGO: A.Balklavs. Ball Lightning and Solar Activity (abridged) ; Streamer with the USSR State Emblem on Mars (TASS materials) ; NEWS: I.Eglītis. Asteroid Baldone – Christmas Gift for Latvia ; I.Eglītis. LUAI Astrophysics Observatory Discovers First Trojan Asteroid ; V.Kalniņš. Exceeding Speed of Light in CERN Experiment from the Theory of Relativity Viewpoint ; O.Dumbrājs. Higgs Boson ; NOBEL PRIZE WINNERS: D.Docenko. Nobel Prize in Physics for Discovery of Accelerating Expansion of Universe ; SPACE RESE…

Zvaigžņotā Debess: 2010, Pavasaris (207)

2010

Contents: E.Cielēns. Have Events in Space Influenced Evolution of Life on the Earth? ; A.Balklavs. Do Pulsars Radiate also in X-Rays? ; Soviet Press materials. Satellite of Friendship In Orbit ; I.Kalviņš. Innovation in Latvia: an Illusion or Reality? ; I.Eglītis. Half Comet-Half Asteroid Discovered With Baldone Schmidt Telescope ; A.Alksnis. While Rosetta is on the Fly from Steins to Lutetia ; M.Gills. Astronomy beyond 2009 ; IAU1001 Press Release. The International Year of Astronomy 2009: The Largest Science Education and Public Outreach Event in History ; J.Limansky. The International Year of Astronomy 2009 in Philately. Series EUROPA ; A.Bruņeniece, I.Dudareva. Wonders of the Solar Syst…