نتایج جستجو برای: foraminifer

تعداد نتایج: 296  

2017
Pierre-Yves Pascal Christine Dupuy Pierre Richard Nathalie Niquil

7 The majority of sediment dweller foraminifera are deposit feeders. They use their 8 pseudopodia to gather sediment with associated algae, organic detritus and bacteria. Uptake of 9 bacteria by foraminifera have been observed but rarely quantified. We measured uptake of 10 bacteria by the common foraminifera Ammonia tepida using 15 N pre-enriched bacteria as 11 tracers. In intertidal flats, se...

2011
Raphaël Morard Frédéric Quillévéré Christophe J. Douady Colomban de Vargas Thibault de Garidel-Thoron Gilles Escarguel

The planktonic foraminiferal morpho-species Globoconella inflata is widely used as a stratigraphic and paleoceanographic index. While G. inflata was until now regarded as a single species, we show that it rather constitutes a complex of two pseudo-cryptic species. Our study is based on SSU and ITS rDNA sequence analyses and genotyping of 497 individuals collected at 49 oceanic stations covering...

2015
K. Kaczmarek

A number of studies have shown that the boron isotopic composition (δB) and the B /Ca ratio of biogenic carbonates (mostly foraminifers) can serve as proxies for two parameters of the ocean’s carbonate chemistry, rendering it possible to calculate the entire carbonate system. However, the B incorporation mechanism into marine carbonates is still not fully understood and analyses of field sample...

2007
Syee Weldeab David W. Lea Ralph R. Schneider Nils Andersen

[1] A Holocene Gulf of Guinea record of riverine runoff, based on Ba/Ca in tests of a shallow-dwelling planktic foraminifer, and sea surface temperature (SST), based on Mg/Ca, reveals centennial-scale instabilities in West African monsoon (WAM) precipitation and eastern equatorial Atlantic (EEA) thermal conditions. The long-term Holocene climate trend is characterized by a warm and wet early-mi...

2011
Caroline Cléroux Peter deMenocal Thomas Guilderson

A current scenario to explain much of the atmospheric CO2 increase during the Glacial to Holocene climate transition requires the outgassing of a deep, old oceanic CO2 reservoir thought to be located in the Southern Ocean. In this scenario, CO2-rich and 14C-depleted subsurface Antarctic-sourced water, ventilates the thermocline where it is purged to the atmosphere in the equatorial regions, a v...

Journal: :Frontiers in Marine Science 2023

Oxygen limited marine environments, such as oxygen minimum zones, are of profound importance for global nutrient cycling and vertical habitat availability. While it is understood that the extent intensity zones responsive to climate, suite viable proxies low pelagic environments continues pose a real barrier paleoclimate interpretations. Here we investigate proxy potential an array trace elemen...

Journal: :Lecture Notes in Computer Science 2022

We apply deep metric learning for the first time to problem of classifying planktic foraminifer shells on microscopic images. This species recognition task is an important information source and scientific pillar reconstructing past climates. All CNN pipelines in literature produce black-box classifiers that lack visualisation options human experts cannot be applied open set problems. Here, we ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید