The carbon isotopic response of algae, (cyano)bacteria, archaea and higher plants to the late Cenomanian perturbation of the global carbon cycle: Insights from biomarkers in black shales from the Cape Verde Basin (DSDP Site 367)

2008 ◽  
Vol 39 (12) ◽  
pp. 1703-1718 ◽  
Author(s):  
Jaap S. Sinninghe Damsté ◽  
Marcel M.M. Kuypers ◽  
Richard D. Pancost ◽  
Stefan Schouten
Keyword(s):  
Carbon Cycle ◽  
Higher Plants ◽  
Global Carbon Cycle ◽  
Black Shales ◽  
Cape Verde ◽  
Carbon Isotopic ◽  
Global Carbon ◽  
Dsdp Site

The stable carbon isotopic composition of organic material in platform derived sediments: implications for reconstructing the global carbon cycle

Sedimentology ◽  
2011 ◽  
Vol 59 (1) ◽  
pp. 319-335 ◽  
Author(s):  
AMANDA M. OEHLERT ◽  
KATHRYN A. LAMB-WOZNIAK ◽  
QUINN B. DEVLIN ◽  
GRETA J. MACKENZIE ◽  
JOHN J. G. REIJMER ◽  
...  
Keyword(s):  
Carbon Cycle ◽  
Isotopic Composition ◽  
Organic Material ◽  
Carbon Isotopic Composition ◽  
Global Carbon Cycle ◽  
Stable Carbon ◽  
Carbon Isotopic ◽  
Global Carbon

scholarly journals An open marine record of the Toarcian oceanic anoxic event

2011 ◽  
Vol 3 (1) ◽  
pp. 385-410 ◽  
Author(s):  
D. R. Gröcke ◽  
R. S. Hori ◽  
J. Trabucho-Alexandre ◽  
D. B. Kemp ◽  
L. Schwark
Keyword(s):  
Organic Matter ◽  
Carbon Cycle ◽  
Carbon Isotope ◽  
Isotope Composition ◽  
Global Carbon Cycle ◽  
Open Ocean ◽  
Black Shales ◽  
Oceanic Anoxic Event ◽  
Anoxic Event ◽  
Global Carbon

Abstract. Oceanic anoxic events were time intervals in the Mesozoic characterized by widespread distribution of marine organic-rich sediments (black shales) and significant perturbations in the global carbon cycle. The expression of these perturbations is globally recorded in sediments as excursions in the carbon isotope record irrespective of lithology or depositional environment. During the Early Toarcian, black shales were deposited on the epi- and peri-continental shelves of Pangaea and these sedimentary rocks are associated with a pronounced (ca. 7‰) negative (organic) carbon isotope excursion (CIE) which is thought to be the result of a major perturbation in the global carbon cycle. For this reason, the Early Toarcian is thought to represent an oceanic anoxic event (the T-OAE). Associated with this event, there were pronounced perturbations in global weathering rates and seawater temperatures. Although it is commonly asserted that the T-OAE is a global event and that the distribution of black shales is likewise global, an isotopic and/or organic-rich expression of this event has as yet only been recognized on epi- and peri-continental Pangaean localities. To address this issue, the carbon isotope composition of organic matter (δ13Corg) of Early Toarcian cherts from Japan that were deposited in the open Panthalassa Ocean was analysed. The results show the presence of a major (>6‰) negative excursion in δ13Corg that, based on radiolarian biostratigraphy, is a correlative of the Early Toarcian negative CIE known from European epicontinental strata. Furthermore, a secondary ca. −2‰ excursion in δ13Corg is also recognized lower in the studied succession that, within the current biostratigraphical resolution, is likely to represent the excursion that occurs close to the Pliensbachian/Toarcian boundary and which is also recorded in European epicontinental successions. These results from the open ocean realm suggest that, in conjunction with other previously published datasets, these major Early Jurassic carbon cycle perturbations affected all active global reservoirs of the exchangeable carbon cycle (deep marine, shallow marine, atmospheric). An extremely negative δ13Corg value (−57‰) during the peak of the T-OAE is also reported, which suggests that the inferred open ocean mid-water oxygen minimum layer within which these sediments are thought to have been deposited was highly enriched in methanotrophic bacteria, since these organisms are the only plausible producers of such 12C-enriched organic matter.

scholarly journals An open ocean record of the Toarcian oceanic anoxic event

Solid Earth ◽  
2011 ◽  
Vol 2 (2) ◽  
pp. 245-257 ◽  
Author(s):  
D. R. Gröcke ◽  
R. S. Hori ◽  
J. Trabucho-Alexandre ◽  
D. B. Kemp ◽  
L. Schwark
Keyword(s):  
Organic Matter ◽  
Carbon Cycle ◽  
Carbon Isotope ◽  
Isotope Composition ◽  
Global Carbon Cycle ◽  
Open Ocean ◽  
Black Shales ◽  
Oceanic Anoxic Event ◽  
Anoxic Event ◽  
Global Carbon

Abstract. Oceanic anoxic events were time intervals in the Mesozoic characterized by widespread distribution of marine organic matter-rich sediments (black shales) and significant perturbations in the global carbon cycle. These perturbations are globally recorded in sediments as carbon isotope excursions irrespective of lithology and depositional environment. During the early Toarcian, black shales were deposited on the epi- and pericontinental shelves of Pangaea, and these sedimentary rocks are associated with a pronounced (ca. 7 ‰) negative (organic) carbon isotope excursion (CIE) which is thought to be the result of a major perturbation in the global carbon cycle. For this reason, the lower Toarcian is thought to represent an oceanic anoxic event (the T-OAE). If the T-OAE was indeed a global event, an isotopic expression of this event should be found beyond the epi- and pericontinental Pangaean localities. To address this issue, the carbon isotope composition of organic matter (δ13Corg of lower Toarcian organic matter-rich cherts from Japan, deposited in the open Panthalassa Ocean, was analysed. The results show the presence of a major (>6 ‰) negative excursion in δ13Corg that, based on radiolarian biostratigraphy, is a correlative of the lower Toarcian negative CIE known from Pangaean epi- and pericontinental strata. A smaller negative excursion in δ13Corg (ca. 2 ‰) is recognized lower in the studied succession. This excursion may, within the current biostratigraphic resolution, represent the excursion recorded in European epicontinental successions close to the Pliensbachian/Toarcian boundary. These results from the open ocean realm suggest, in conjunction with other previously published datasets, that these Early Jurassic carbon cycle perturbations affected the active global reservoirs of the exchangeable carbon cycle (deep marine, shallow marine, atmospheric).

Are response function representations of the global carbon cycle ever interpretable?

Tellus B ◽  
2009 ◽  
Vol 61 (2) ◽  
Author(s):  
Sile Li ◽  
Andrew J. Jarvis ◽  
David T. Leedal
Keyword(s):  
Carbon Cycle ◽  
Response Function ◽  
Global Carbon Cycle ◽  
Global Carbon

EPR-derived structures of flavin radical and iron-sulfur clusters from Methylosinus sporium 5 reductase

2021 ◽  
Author(s):  
Han Sol Jeong ◽  
Sugyeong Hong ◽  
Hee Seon Yoo ◽  
Jin Kim ◽  
Yujeong Kim ◽  
...  
Keyword(s):  
Carbon Cycle ◽  
Crucial Role ◽  
Methane Monooxygenase ◽  
Global Carbon Cycle ◽  
Ambient Conditions ◽  
Iron Sulfur Clusters ◽  
Iron Sulfur ◽  
Greenhouse Effects ◽  
Global Carbon ◽  
Significant Attention

Methane monooxygenase (MMO) has attracted significant attention owing to its crucial role in the global carbon cycle; it impedes greenhouse effects by converting methane to methanol under ambient conditions. The...

scholarly journals Amazonian Fire Events Disturbed the Global Carbon Cycle: A Study from 2019 Amazon Wildfire Using Google Earth Engine

2020 ◽  
Vol 3 (1) ◽  
pp. 43
Author(s):  
Subhajit Bandopadhyay ◽  
Dany A. Cotrina Sánchez
Keyword(s):  
Carbon Cycle ◽  
Carbon Sink ◽  
Brazilian Amazon ◽  
Global Carbon Cycle ◽  
Forest Productivity ◽  
Google Earth ◽  
Comparative Approach ◽  
Burned Area ◽  
Google Earth Engine ◽  
Global Carbon

An unprecedented number of wildfire events during 2019 throughout the Brazilian Amazon caught global attention, due to their massive extent and the associated loss in the Amazonian forest—an ecosystem on which the whole world depends. Such devastating wildfires in the Amazon has strongly hampered the global carbon cycle and significantly reduced forest productivity. In this study, we have quantified such loss of forest productivity in terms of gross primary productivity (GPP), applying a comparative approach using Google Earth Engine. A total of 12 wildfire spots have been identified based on the fire’s extension over the Brazilian Amazon, and we quantified the loss in productivity between 2018 and 2019. The Moderate Resolution Imaging Spectroradiometer (MODIS) GPP and MODIS burned area satellite imageries, with a revisit time of 8 days and 30 days, respectively, have been used for this study. We have observed that compared to 2018, the number of wildfire events increased during 2019. But such wildfire events did not hamper the natural annual trend of GPP of the Amazonian ecosystem. However, a significant drop in forest productivity in terms of GPP has been observed. Among all 11 observational sites were recorded with GPP loss, ranging from −18.88 gC m−2 yr−1 to −120.11 gC m−2 yr−1, except site number 3. Such drastic loss in GPP indicates that during 2019 fire events, all of these sites acted as carbon sources rather than carbon sink sites, which may hamper the global carbon cycle and terrestrial CO2 fluxes. Therefore, it is assumed that these findings will also fit for the other Amazonian wildfire sites, as well as for the tropical forest ecosystem as a whole. We hope this study will provide a significant contribution to global carbon cycle research, terrestrial ecosystem studies, sustainable forest management, and climate change in contemporary environmental sciences.

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