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Coccolithophore calcification: Changing paradigms in …

Coccolithophores show large variations in coccolith morphology and complexity (Fig. 1) and many contemporary studies have focused on their responses to changing ocean …

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A new method for isolating and analysing coccospheres within …

Coccolithophores are a highly abundant and ubiquitous group of single-celled phytoplankton that are a critical component of global biogeochemical cycles 1.The importance of coccolithophores to ...

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Two Production Stages of Coccolithophores in Winter as Revealed …

Coccolithophores are a kind of marine unicellular algae. They can secrete calcareous scales named coccoliths around their cells. These scales can record the environmental conditions, for example, temperature and CO 2 of surface ocean, when coccolithophores are alive. After death, these scales settle to the seafloor and are stored in sediments for …

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Coccolithophores : From Molecular Processes to Global …

Coccolithophores are emerging as a prime model for interdisciplinary global change research due to their great abundance, wide distribution and exemplary geological record. The results presented in this book address the fundamental question of the interaction between the biota and the environment at various temporal and spatial scales.

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Two Production Stages of Coccolithophores in Winter as …

1 Introduction. Coccolithophores are a kind of marine phytoplankton and play important roles in biogeochemistry cycles. They fix organic carbon via photosynthesis and lower …

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Coccolithophores: an environmentally significant and …

coccolithophores are found to prefer placid, nutrient-poor waters with moderate temperatures (Young et al. 2009). This does not negate the fact that they are also found in cold nutrient carrying upwelled waters. Coccolithophores can thrive very successfully in those areas where other phytoplankton starves to survive (Young et al. 2009).

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Blooming around the world: A story of coccolithophore co …

Coccolithophores are a cosmopolitan phytoplankton adorned with outer plates made of calcium carbonate, a form of inorganic carbon that is the same material found in seashells and classroom chalk. Globally, coccolithophores are estimated to make up anywhere from 5 to 40% of the global primary production, or food creation using photosynthesis.

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Why marine phytoplankton calcify | Science Advances

An estimated 200 species of coccolithophores live in the modern ocean across a wide spectrum of surface ocean environments, ranging from highly productive eutrophic waters in temperate and subpolar regions to the permanently oligotrophic waters of the subtropical gyres.Coccolithophores usually contribute to 1 to 10% of primary production and …

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Coccolithophore biomineralization: New questions, new …

Abstract. Coccolithophores are unicellular phytoplankton that are characterized by the presence intricately formed calcite scales (coccoliths) on their surfaces. In most cases …

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UCLA research shows how carbon-filled oceans affect a tiny …

But coccolithophores, a single-celled plankton, have an outsized effect on oceans due to their sheer quantity — their blooms are visible from space — and because of the fundamental role they play in food chains and the carbon cycle. Small fish and zooplankton feast on them, and they remove huge amounts of carbon from the ocean. ...

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Coccolithophore Cell Biology: Chalking Up Progress

Coccolithophores occupy a special position within the marine phytoplankton because of their production of intricate calcite scales, or coccoliths. Coccolithophores are major …

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Biology and Paleontology of Coccolithophores (Haptophytes)

Coccolithophores are common and widespread components of the marine plankton. They play important roles in the oceanic carbon cycle by both calcification of coccoliths and …

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Eocene emergence of highly calcifying coccolithophores …

Highly calcifying, larger coccolithophores emerged as CO2 generally declined through the Eocene, despite cooling leading to lower organic-matter fixation rates, according to size-dependent ...

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Coccolithophores | Palaeontology and life history

Coccolithophores are one of the primary algal groups in the oceans. They are the focus of research in many disciplines due to their importance in palaeoenvironmental reconstruction and stratigraphy. The book starts with a history of coccolithophore studies followed by chapters discussing coccolithophore biology, and the composition, function ...

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Coccolithophore growth and calcification in a changing ocean

Coccolithophores are widespread throughout the global ocean, from high latitudes to the tropics (from ∼ 70 ° N to ∼ 60 ° S), with subgroups specialized for growth in nearly every oceanic environment (Fig. 2 a). Mean annual surface PIC concentrations underlying coccolithophore subgroup biogeography Fig. 2 a in combination with uncultured species …

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Malformation in coccolithophores in low pH waters: …

Coccolithophores are one of the key actors of the climate system, as they provide ballast for sinking organic debris besides playing an important role in the marine biogeochemical cycles (Riebesell et al. 2009; Taylor et al. 2017).Coccolithophores are single-celled calcifying algae of the division haptophyta and class Prymnesiophyceae that produce …

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Spatial and Temporal Variability of

For example, it has been argued that coccolithophores may be a less desirable food source for microzooplankton in this region based on studies measuring growth and grazing for the <10-μm chlorophyll a size fraction (Olson & Strom, 2002), although new research measuring changes in coccolithophore cell counts has shown high mortality of ...

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A coastal coccolithophore maintains pH homeostasis and

Uptake of dissolved boron species by coccolithophores. The coccolith δ 11 B values, fractionated from the culture medium δ 11 B of 0.64‰, range from −15‰ to −25‰ (Fig. 1).Although ...

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Coccolithophores, photosynthetic unicellular algae – …

Coccolithophores are closely related to a group of organisms (Haptophytes) that lack the plates. These two groups, together with some other organisms, have been classified a number of different ways. In a five-kingdom classification they are considered to be in the phylum Haptophyta in the kingdom Protista. The coccolithophores are sometimes ...

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Illuminating the Carbon Cycle: Coccolithophores' Ability To …

Coccolithophores, a globally ubiquitous type of phytoplankton, play an essential role in the cycling of carbon between the ocean and atmosphere. New research from Bigelow Laboratory for Ocean Sciences shows that these vital microbes can survive in low-light conditions by taking up dissolved organic forms of carbon, forcing researchers to ...

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Frontiers | An Extracellular Polysaccharide-Rich Organic Layer

Coccolithophores are globally abundant marine microalgae characterized by their ability to form calcite platelets (coccoliths). The coccoliths are produced internally in a Golgi-derived vesicle. Mature coccoliths are extruded from the cell to form a protective covering on the cell surface, known as the coccosphere. Current evidence indicates that calcite precipitation …

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On the Genesis and Function of Coccolithophore Calcification

The functional group of coccolithophores consists of calcifying eukaryotic unicellular phytoplankton that produces minuscule CaCO 3 structures, named coccoliths, surrounding the cell, and forming a coccosphere. Coccolithophores occupy an important role in carbon cycling dynamics over short and geological time scales due to the process of …

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Mixotrophic uptake of organic compounds by coccolithophores

Coccolithophores are predominantly marine, unicellular algae generally thought of as photoautotrophs and covered with "coccoliths," scales made of calcium carbonate. Taxonomically, coccolithophores fall into two orders, Isochrysidales and Coccolithales, within the Haptophyta phylum (Adl et al. 2019).

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Cycling carbon with coccolithophores | Nature Geoscience

Cellular modelling and geochemical analyses reveal that a dominant group of phytoplankton changed their carbonate production as atmospheric CO2 levels declined from peak levels in the warm early ...

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Species composition of extant coccolithophores including …

Species composition. A total of 46 extant coccolithophore taxa, two of which are represented by both hetero- and holococcolith forms, were identified from 160 samples …

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Coccolithophore calcification: Changing paradigms in changing …

Coccolithophores show large variations in coccolith morphology and complexity (Fig. 1) and many contemporary studies have focused on their responses to changing ocean conditions, particularly the changes in carbonate chemistry associated with ocean acidification [e.g. 5].From a cellular perspective, key questions in coccolithophore …

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Coccolithophore community response to ocean acidification …

Coccolithophores are a group of calcifying phytoplankton that can reach high abundances in the Mediterranean Sea, and whose responses to OA are modulated by temperature and nutrients. We present the results of the first land-based mesocosm experiment testing the effects of combined OA and OW on an oligotrophic Eastern Mediterranean ...

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High resolution spatial analyses of trace elements in

Coccolithophores are phytoplanktonic algae which produce an exoskeleton made of single platelets of calcite named coccoliths. They are widespread in all oceans and directly impact the short- and ...

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Coccolithophore community response to ocean acidification …

Coccolithophores are a group of calcifying phytoplankton that can reach high abundances in the Mediterranean Sea, and whose responses to OA are modulated by temperature and nutrients. We present ...

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Coccolithophore biomineralization: New questions, new …

Coccolithophores also present a paradigm for the study of calcification mechanisms. The ease with which certain species can be cultured and the relative tractability of a unicellular calcification system that produces intricate calcium carbonate structures (coccoliths) allows questions relating to the biological control of crystal formation and ...

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