scholarly journals Carbon isotope variations in the Upper Carboniferous - Pennian Mallemuk Mountain Group, eastern North Greenland

1989 ◽  
Vol 37 ◽  
pp. 205-211
Author(s):  
Lars Stemmerik ◽  
Mordeckai Magaritz
Keyword(s):  
Organic Carbon ◽  
Sea Level ◽  
Global Carbon Cycle ◽  
Late Permian ◽  
Early Permian ◽  
Isotopic Data ◽  
Upper Carboniferous ◽  
Global Carbon ◽  
Early Late ◽  
North Greenland

Isotope data from Late Palaeozoic limestones of the Wandel Sea Basin in eastern North Greenland show a variation of b13C from 0.0 %o to 5.7 %o vs PDB. Carbonates depleted in 13C occur in the basal part of lower Moscovian, upper Moscovian and middle Gzhelian transgressive sequences. 13C enriched limestones occur later in the cycles. The most 13C enriched limestones occur in the youngest (late Early Permian-early Late Permian) part of the sequence in Amdrup Land. The isotopic data is believed to represent changes in the global carbon cycle. Thus 13C enriched carbonates correlate to periods of burial of organic carbon mostly as coal, while 13C depleted carbonates formed as the result of erosion and oxidation of organic carbon during sea-level low stands.

First Permo-Carboniferous conodonts from North Greenland

1996 ◽  
Vol 133 (5) ◽  
pp. 553-564 ◽  
Author(s):  
Jan Audun Rasmussen ◽  
Eckart Håkansson
Keyword(s):  
Early Permian ◽  
Upper Carboniferous ◽  
The North ◽  
First Time ◽  
North Greenland

AbstractUpper Palaeozoic conodonts are described for the first time from the North Greenland Wandel Sea Basin. In eastern Peary Land, the Moscovian species Idiognathodus incurvus and the Kasimovian—Gzhelian I. magnificus occur in the Upper Carboniferous Foldedal Formation, while an assemblage from the lower part of the succeeding Kim Fjelde Formation suggests deposition in the Upper Artinskian Neostreptognathodus pequopensis—N. clarki Zone. These datings confirm the existence in the northern part of the Wandel Sea Basin of the pronounced early Permian hiatus previously recognized in Holm Land and Amdrup Land in the southern part of the basin. The single conodont specimen found at Prinsesse Ingeborg Halvø further corrobates the local absence of this regional hiatus in the central part of the Wandel Sea Basin.

scholarly journals ABOUT ROLE OF PHOTOSYNTHESIS IN CARBON TURNOVER

2019 ◽  
Vol 47 (4) ◽  
pp. 76-87
Author(s):  
A. A. Ivlev
Keyword(s):  
Organic Carbon ◽  
Carbon Cycle ◽  
Sulfate Reduction ◽  
Subduction Zone ◽  
Global Carbon Cycle ◽  
Carbon Turnover ◽  
Sedimentary Organic Carbon ◽  
Lithospheric Plates ◽  
Global Carbon

The article considers the model of the global carbon cycle, in which photosynthesis is one of the key elements. The model itself is considered as the transition of carbon from the oxidized state to the reduced one and back. This transition is carried out by photosynthesis. The main oxidation of sedimentary organic carbon and its transition to an oxidized form is carried out by means of a natural reaction of thermochemical sulfate reduction, which occurs in the subduction zone (the zone of collision of lithospheric plates). A number of natural facts substantiating some key provisions of the model are given.

scholarly journals Increasing Autochthonous Production in Inland Waters as a Contributor to the Missing Carbon Sink

2021 ◽  
Vol 9 ◽  
Author(s):  
Zaihua Liu ◽  
Hao Yan ◽  
Sibo Zeng
Keyword(s):  
Organic Carbon ◽  
Carbon Cycle ◽  
Carbon Sink ◽  
Global Carbon Cycle ◽  
Inland Waters ◽  
Organic Carbon Burial ◽  
Missing Carbon Sink ◽  
Organic Carbon Storage ◽  
Autochthonous Production ◽  
Global Carbon

Accounting for the residual land sink (or missing carbon sink) has become a major budget focus for global carbon cycle modelers. If we are not able to account for the past and current sources and sinks, we cannot make accurate predictions about future storage of fossil fuel combustion emissions of carbon in the terrestrial biosphere. Here, we show that the autochthonous production (AP) in inland waters appears to have been strengthening in response to changes in climate and land use, as evidenced by decreasing CO2 emissions from and increasing dissolved organic carbon storage and/or organic carbon burial in inland waters during recent decades. The increasing AP may be due chiefly to increasing aquatic photosynthesis caused by global warming and intensifying human activities. We estimate that the missing carbon sink associated with the strengthening AP in inland waters may range from 0.38 to 1.8 Gt C yr-1 with large uncertainties. Our study stresses the potential role that AP may play in the further evolution of the global carbon cycle. Quantitative estimates of future freshwater AP effects on the carbon cycle may also help to guide the action needed to reduce carbon emissions, and increase carbon sinks in terrestrial aquatic ecosystems.

Mercury evidence from the Sino-Korean block for Emeishan volcanism during the Capitanian mass extinction

2018 ◽  
Vol 156 (06) ◽  
pp. 1105-1110 ◽  
Author(s):  
HYOSANG KWON ◽  
MUN GI KIM ◽  
YONG IL LEE
Keyword(s):  
Organic Carbon ◽  
Mass Extinction ◽  
Volcanic Eruptions ◽  
Global Carbon Cycle ◽  
Upper Permian ◽  
South China Block ◽  
Extinction Event ◽  
Tethys Ocean ◽  
Mass Extinction Event ◽  
Global Carbon

AbstractA prominent large negative δ13Corg excursion and a coeval notable spike in mercury (Hg)/total organic carbon ratio are observed in the middle–upper Permian Gohan Formation in central Korea, located in the eastern Sino-Korean block (SKB), which may represent the Capitanian mass extinction event. The SKB was separated from the South China block by the eastern Palaeo-Tethys Ocean. This finding from the SKB supports the widespread Hg loading to the environment emitted from the Emeishan volcanic eruptions in SW China. This study demonstrates that the Hg cycle was globally perturbed in association with global carbon cycle perturbation that occurred during the Capitanian Extinction.

scholarly journals First pan-Arctic assessment of dissolved organic carbon in lakes of the permafrost region

2021 ◽  
Vol 18 (12) ◽  
pp. 3917-3936
Author(s):  
Lydia Stolpmann ◽  
Caroline Coch ◽  
Anne Morgenstern ◽  
Julia Boike ◽  
Michael Fritz ◽  
...  
Keyword(s):  
Climate Change ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Carbon Cycle ◽  
Dissolved Organic Carbon ◽  
Significant Relationship ◽  
Global Carbon Cycle ◽  
Doc Concentration ◽  
Global Carbon ◽  
Permafrost Regions

Abstract. Lakes in permafrost regions are dynamic landscape components and play an important role for climate change feedbacks. Lake processes such as mineralization and flocculation of dissolved organic carbon (DOC), one of the main carbon fractions in lakes, contribute to the greenhouse effect and are part of the global carbon cycle. These processes are in the focus of climate research, but studies so far are limited to specific study regions. In our synthesis, we analyzed 2167 water samples from 1833 lakes across the Arctic in permafrost regions of Alaska, Canada, Greenland, and Siberia to provide first pan-Arctic insights for linkages between DOC concentrations and the environment. Using published data and unpublished datasets from the author team, we report regional DOC differences linked to latitude, permafrost zones, ecoregions, geology, near-surface soil organic carbon contents, and ground ice classification of each lake region. The lake DOC concentrations in our dataset range from 0 to 1130 mg L−1 (10.8 mg L−1 median DOC concentration). Regarding the permafrost regions of our synthesis, we found median lake DOC concentrations of 12.4 mg L−1 (Siberia), 12.3 mg L−1 (Alaska), 10.3 mg L−1 (Greenland), and 4.5 mg L−1 (Canada). Our synthesis shows a significant relationship between lake DOC concentration and lake ecoregion. We found higher lake DOC concentrations at boreal permafrost sites compared to tundra sites. We found significantly higher DOC concentrations in lakes in regions with ice-rich syngenetic permafrost deposits (yedoma) compared to non-yedoma lakes and a weak but significant relationship between soil organic carbon content and lake DOC concentration as well as between ground ice content and lake DOC. Our pan-Arctic dataset shows that the DOC concentration of a lake depends on its environmental properties, especially on permafrost extent and ecoregion, as well as vegetation, which is the most important driver of lake DOC in this study. This new dataset will be fundamental to quantify a pan-Arctic lake DOC pool for estimations of the impact of lake DOC on the global carbon cycle and climate change.

scholarly journals Spatiotemporal Differentiation of Soil Organic Carbon of Grassland and Its Relationship with Soil Physicochemical Properties on the Northern Slope of Qilian Mountains, China

2020 ◽  
Vol 12 (22) ◽  
pp. 9396
Author(s):  
Le Yang ◽  
Wenxiong Jia ◽  
Yang Shi ◽  
Zhiyuan Zhang ◽  
Hui Xiong ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Carbon Cycle ◽  
Physicochemical Properties ◽  
Soil Depth ◽  
Global Carbon Cycle ◽  
Qilian Mountains ◽  
Forest Steppe ◽  
Northern Slope ◽  
Global Carbon

The soil organic carbon pool is an important part of the global carbon cycle, and its accumulation and decomposition affect the balance of the global carbon cycle. It is important to understand scientifically the temporal and spatial variation of soil organic carbon (SOC) and its influencing factors, which could aid further understanding of the accumulation and decomposition of SOC. In order to reveal the relationship between soil organic carbon and soil’s physicochemical properties, six plots were selected on the east, middle and west of forest steppes and typical grasslands on the northern slope of Qilian Mountains during two consecutive growing seasons from 2013 to 2014. Soil samples under 0–30 cm were used to study the spatiotemporal differentiation of SOC and its relationship with the soil’s physicochemical properties in the grassland of the study area. The results show that the content of SOC in the grassland in 2013 was higher than that in 2014, and that it decreased gradually from east to west. The content of SOC is significantly different between the soil layer of 0–10 cm and the soil layers of 10–20 cm and 20–30 cm (p < 0.05), and it decreases with increases in soil depth. The SOC content on forest steppe is higher than that on typical grassland. Significant positive correlations appear between SOC with soil water content and soil nutrients (alkaline nitrogen, available phosphorus, available potassium) (p < 0.01), but there are significant negative correlations between SOC and soil temperature, soil pH, and soil electrical conductivity (p < 0.01).

First report of microorganisms of Caucasus glaciers (Georgia)

Biologia ◽  
2016 ◽  
Vol 71 (6) ◽  
Author(s):  
Nicoletta Makowska ◽  
Krzysztof Zawierucha ◽  
Joanna Mokracka ◽  
Ryszard Koczura
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Carbon Cycle ◽  
Sea Level Rise ◽  
Sea Level ◽  
Global Carbon Cycle ◽  
Rrna Gene ◽  
Extreme Conditions ◽  
First Report ◽  
Global Carbon

AbstractGlaciers constitute freshwater reservoirs. They are the main contributors to sea level rise, play an important role in global carbon cycle and are the source of water for people. Despite extreme conditions, they are also a habitat for a number of cryophilic organisms. To fill the gap in the knowledge on the biota on glaciers in Caucasus, the aim of the study was to: (i) isolate and enumerate culturable heterotrophs; (ii) determine the number of coliforms and enterococci bacteria; and (iii) analyze total microbial 16S rRNA gene in cryoconite sediments, ice and gravel. The material was collected from two glaciers in Caucasus (Georgia, Svaneti region). Bacteria

Sign in / Sign up

Export Citation Format

Share Document