Journal ArticleDOI
Production and accumulation of calcium carbonate in the ocean: Budget of a nonsteady state
TLDR
In this article, it was shown that the oceans are not presently in a steady state, suggesting that outputs have been overestimated or inputs underestimated, that one or more other inputs have not been identified, and/or that one of the missing calcium sources might be groundwater, although its presentday input is probably much smaller than that of rivers.Abstract:
Present-day production of CaCO3 in tne world ocean is calculated to be about 5 billion tons (bt) per year, of which about 3 bt accumulate in sediments; the other 40% is dissolved. Nearly half of the carbonate sediment accumulates on reefs, banks, and tropical shelves, and consists largely of metastable aragonite and magnesian calcite. Deep-sea carbonates, predominantly calcitic coccoliths and planktonic foraminifera, have orders of magnitude lower productivity and accumulation rates than shallow-water carbonates, but they cover orders of magnitude larger basin area. Twice as much calcium is removed from the oceans by present-day carbonate accumulation as is estimated to be brought in by rivers and hydrothermal activity (1.6 bt), suggesting that outputs have been overestimated or inputs underestimated, that one or more other inputs have not been identified, and/or that the oceans are not presently in steady state. One “missing” calcium source might be groundwater, although its present-day input is probably much smaller than that of rivers. If, as seems likely, CaCO3 accumulation presently exceeds terrestial and hydrothermal input, this imbalance presumably is offset by decreased accumulation and increased input during lowered sea level: shallow-water accumulation decreases by an order of magnitude with a 100 m drop in sea level, while groundwater influx increases because of heightened piezometric head and the diagenesis of metastable aragonite and magnesian calcite from subaerially exposed shallow-water carbonates.read more
Citations
More filters
Journal ArticleDOI
Strong tidal currents and labile organic matter stimulate benthic decomposition and carbonate fluxes on the southern Great Barrier Reef shelf
TL;DR: In this paper, the authors measured the rate and pathways of benthic carbon decomposition and carbonate kinetics in relation to the presence on the outer shelf of the Pompey Reef Complex (PRC).
Journal ArticleDOI
Coccolithophore community response to ocean acidification and warming in the Eastern Mediterranean Sea: results from a mesocosm experiment
Barbara D'Amario,Carlos Pérez,Michaël Grelaud,Paraskevi Pitta,Evangelia Krasakopoulou,Patrizia Ziveri +5 more
TL;DR: The results of the first land-based mesocosm experiment testing the effects of combined OA and OW on an oligotrophic Eastern Mediterranean coccolithophore community suggest that the projected increase in sea surface temperatures, including marine heatwaves, will cause rapid changes in Eastern Mediterranean rowing communities, and that these effects will be exacerbated by OA.
Journal ArticleDOI
Ocean acidification alters the calcareous microstructure of the green macro-alga Halimeda opuntia
André Wizemann,Friedrich Wilhelm Meyer,Laurie C. Hofmann,Christian Wild,Christian Wild,Hildegard Westphal,Hildegard Westphal +6 more
TL;DR: In this article, the authors used scanning electron microscopy to examine changes of the CaCO3 segment microstructure of Halimeda opuntia specimens that had been exposed to artificially elevated seawater pCO2 of ~650 µatm for 45 days.
Journal ArticleDOI
From platform top to adjacent deep sea: New source-to-sink insights into carbonate sediment production and transfer in the SW Indian Ocean (Glorieuses archipelago)
Stephan J. Jorry,Gwenael Jouet,Evan N. Edinger,Samuel Toucanne,John W. Counts,Elda Miramontes,Simon Courgeon,Natalia Vázquez Riveiros,Pascal Roy,Gilbert Camoin +9 more
TL;DR: In this paper, a source-to-sink study dedicated to a pure carbonate system, located in the SW Indian Ocean (Glorieuses archipelago), is presented, where extensive field sampling and geophysical acquisition across the carbonate platform have allowed to estimate the composition, the lateral variability, and volumes of neritic sands deposited on the platform top.
Journal ArticleDOI
Incorporating benthic community changes into hydrochemical-based projections of coral reef calcium carbonate production under ocean acidification
TL;DR: In this article, the authors present a framework for hydrochemical studies that allows both declining net calcification rates and changes in benthic community composition to be incorporated into projections of coral reef CaCO3 production.
References
More filters
Journal ArticleDOI
A 17,000-year glacio-eustatic sea level record: influence of glacial melting rates on the Younger Dryas event and deep-ocean circulation
TL;DR: In this paper, a global oxygen isotope record for ocean water has been calculated from the Barbados sea level curve, allowing separation of the ice volume component common to all isotope records measured in deep-sea cores.
Journal ArticleDOI
The carbonate-silicate geochemical cycle and its effect on atmospheric carbon dioxide over the past 100 million years
TL;DR: In this article, a computer model has been constructed that considers the effects on the CO/sub 2/ level of the atmosphere, and the Ca, Mg, and HCO/sub 3/ levels of the ocean, of the following processes: weathering on the continents of calcite, dolomite, and calcium-and-magnesium-containing silicates; biogenic precipitation and removal of CaCO 3/from the ocean; removal of Mg from the ocean via volcanic-seawater reaction; and the metamorphic-magmatic decarbon
Journal ArticleDOI
Vostok ice core provides 160,000-year record of atmospheric CO2
TL;DR: In this article, direct evidence of past atmospheric CO2 changes has been extended to the past 160,000 years from the Vostok ice core, showing an inherent phenomenon of change between glacial and interglacial periods.
Journal ArticleDOI
Biological communities at the Florida escarpment resemble hydrothermal vent taxa.
Charles K. Paull,Barbara Hecker,R.F. Commeau,R. P. Freeman-Lynde,C. Neumann,W.P. Corso,Stjepko Golubic,J.E. Hook,Elisabeth L. Sikes,Joseph R. Curray +9 more
TL;DR: Dense biological communities of large epifaunal taxa similar to those found along ridge crest vents at the East Pacific Rise were discovered in the abyssal Gulf of Mexico.
Journal ArticleDOI
A biogeochemical study of the coccolithophore, Emiliania huxleyi, in the North Atlantic
Patrick M. Holligan,Emilio Fernández,James Aiken,William M. Balch,Philip W. Boyd,Peter H. Burkill,Miles S. Finch,Stephen B. Groom,Gillian Malin,Kerstin Muller,Duncan A. Purdie,Carol V. Robinson,Charles C. Trees,Suzanne M. Turner,Paul van der Wal +14 more
TL;DR: The biogeochemical properties of an extensive bloom (∼250,000 km2) of the coccolithophore, Emiliania huxleyi, in the north east Atlantic Ocean were investigated in June 1991.
Related Papers (5)
Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms
James C. Orr,Victoria J. Fabry,Olivier Aumont,Laurent Bopp,Scott C. Doney,Richard A. Feely,Anand Gnanadesikan,Nicolas Gruber,Akio Ishida,Fortunat Joos,Robert M. Key,Keith Lindsay,Ernst Maier-Reimer,Richard J. Matear,Patrick Monfray,Anne Mouchet,Raymond G. Najjar,Gian-Kasper Plattner,Keith B. Rodgers,Christopher L. Sabine,Jorge L. Sarmiento,Reiner Schlitzer,Richard D. Slater,I. Totterdell,Marie-France Weirig,Yasuhiro Yamanaka,Andrew Yool +26 more