Organic carbon burial in a large, deep alpine lake (southwest China) in response to changes in climate, land use and nutrient supply over the past ~100 years

Lacustrine ecosystems are directly influenced by terrestrial soil erosion, and excessive sediment loading constitutes a significant and widespread environmental issue. In order to investigate the response of catchment soil erosion and organic carbon burial to climate change and human activity, a sediment core spanning the last 160 years was retrieved from Lake Chenghai in southwest China. Multi-proxy analysis including grain-size composition and geochemical indicators were undertaken in this study. The result of grain-size vs standard deviation method shows that the sensitive component with a modal size of 13.2 μm is related to fluvial processes and sensitive to the catchment soil erosion. The increasing intensity of soil erosion was mainly determined by the weakening of Indian summer monsoon and global warming, as well as intensive human activities during the middle of 20th century, which resulted in decreasing vegetation cover in Lake Chenghai catchment. The organic carbon burial rate was also attributed to the catchment disturbance, indicating that increased catchment soil erosion may impact the terrestrial carbon recycling.

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Organic carbon burial in Chinese lakes over the past 150 years

Quaternary International ◽

10.1016/j.quaint.2017.03.047 ◽

2017 ◽

Vol 438 ◽

pp. 94-103 ◽

Cited By ~ 11

Author(s):

Fengju Zhang ◽

Shuchun Yao ◽

Bin Xue ◽

Xixi Lu ◽

Zhifan Gui

Keyword(s):

Organic Carbon ◽

The Past ◽

Carbon Burial ◽

Organic Carbon Burial

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What Controls Atmospheric Oxygen Concentrations?

10.23943/princeton/9780691145020.003.0005 ◽

2017 ◽

Author(s):

Donald Eugene Canfield

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Black Sea ◽

Atmospheric Oxygen ◽

Fundamental Question ◽

The Black Sea ◽

Microbial Process ◽

The Past ◽

Carbon Burial ◽

Organic Carbon Burial

This chapter deals with the fundamental question of why there is oxygen in the atmosphere at all. It seeks to identify the main processes controlling the oxygen concentration. Plants and cyanobacteria produce the oxygen, but it accumulates only because some of the original photosynthetically produced organic matter is buried and preserved in sediments. Another oxygen source is an anaerobic microbial process called sulfate reduction that respires organic matter using sulfate and produces sulfide. This process is quite common in nature but are most prominent in relatively isolated basins like the Black Sea, and in most marine sediments at depths where oxygen has been consumed by respiration. If there is iron around, the sulfide reacts with the iron, forming a mineral called pyrite. While organic carbon burial has been the main oxygen source to the atmosphere over the past several hundred million years, for some intervals further back in time, pyrite burial may well have dominated as an oxygen source.

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Spatio-temporal patterns of organic carbon burial in the sediment of Lake Erhai in China during the past 100 years

Journal of Lake Sciences ◽

10.18307/2019.0126 ◽

2019 ◽

Vol 31 (1) ◽

pp. 282-292

Author(s):

LIU Huiji ◽

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LIU Enfeng ◽

YU Zhenzhen ◽

ZHANG Enlou ◽

...

Keyword(s):

Organic Carbon ◽

Temporal Patterns ◽

The Past ◽

Carbon Burial ◽

Organic Carbon Burial ◽

Lake Erhai ◽

Spatio Temporal

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Land-use change, not climate, controls organic carbon burial in lakes

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.1278 ◽

2013 ◽

Vol 280 (1769) ◽

pp. 20131278 ◽

Cited By ~ 65

Author(s):

N. J. Anderson ◽

R. D. Dietz ◽

D. R. Engstrom

Keyword(s):

Land Use ◽

Organic Carbon ◽

Land Cover ◽

Nutrient Loading ◽

Agricultural Land ◽

Central Component ◽

Atmospheric N Deposition ◽

Carbon Burial ◽

Organic Carbon Burial ◽

Burial Rates

Lakes are a central component of the carbon cycle, both mineralizing terrestrially derived organic matter and storing substantial amounts of organic carbon (OC) in their sediments. However, the rates and controls on OC burial by lakes remain uncertain, as do the possible effects of future global change processes. To address these issues, we derived OC burial rates in 210 Pb-dated sediment cores from 116 small Minnesota lakes that cover major climate and land-use gradients. Rates for individual lakes presently range from 7 to 127 g C m –2 yr –1 and have increased by up to a factor of 8 since Euro-American settlement (mean increase: 2.8×). Mean pre-disturbance OC burial rates were similar (14–22 g C m –2 yr –1 ) across all land-cover categories (prairie, mixed deciduous and boreal forest), indicating minimal effect of the regional temperature gradient (approx. 4°C) on background carbon burial. The relationship between modern OC burial rates and temperature was also not significant after removal of the effect of total phosphorus. Contemporary burial rates were strongly correlated with lake-water nutrients and the extent of agricultural land cover in the catchment. Increased OC burial, documented even in relatively undisturbed boreal lake ecosystems, indicates a possible role for atmospheric nitrogen deposition. Our results suggest that globally, future land-cover change, intensification of agriculture and associated nutrient loading together with atmospheric N-deposition will enhance OC sequestration by lakes.

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Sediment Organic Carbon Sequestration of Balkhash Lake in Central Asia

Sustainability ◽

10.3390/su13179958 ◽

2021 ◽

Vol 13 (17) ◽

pp. 9958

Author(s):

Wen Liu ◽

Long Ma ◽

Jilili Abuduwaili ◽

Gulnura Issanova ◽

Galymzhan Saparov

Keyword(s):

Carbon Sequestration ◽

Organic Carbon ◽

The Past ◽

Burial Rate ◽

Carbon Burial ◽

Sediment Organic Carbon ◽

Organic Carbon Burial ◽

Organic Carbon Burial Rate ◽

Organic Carbon Sequestration ◽

Global Carbon

As an important part of the global carbon pool, lake carbon is of great significance in the global carbon cycle. Based on a study of the sedimentary proxies of Balkhash Lake, Central Asia’s largest lake, changes in the organic carbon sequestration in the lake sediments and their possible influence over the past 150 years were studied. The results suggested that the organic carbon in the sediments of Lake Balkhash comes mainly from aquatic plants. The organic carbon burial rate fluctuated from 8.16 to 30.04 g·m−2·a−1 and the minimum appeared at the top of the core. The organic carbon burial rate continues to decline as it has over the past 150 years. Global warming, higher hydrodynamic force, and low terrestrial input have not been conducive to the improvement of organic carbon sequestration in Balkhash Lake; the construction of a large reservoir had a greater impact on the sedimentary proxy of total organic carbon content, which could lead to a large deviation for environmental reconstruction. This is the first study to assess the sediment organic carbon sequestration using the modern sediments of Central Asia’s largest lake, which is of great scientific significance. The results contribute to an understanding of organic carbon sequestration in Central Asia and may provide a scientific basis for carbon balance assessment in regional and global scales.

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Oceanic Changes Correlate with Methane Seepage

Eos ◽

10.1029/2020eo145301 ◽

2020 ◽

Vol 101 ◽

Author(s):

Hannah Thomasy

Keyword(s):

Organic Carbon ◽

Sea Level ◽

The Past ◽

Methane Seepage ◽

Carbon Burial ◽

Organic Carbon Burial

Changes in sea level and organic carbon burial may have affected seafloor methane seepage over the past 150 million years.

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A diurnal carbon engine explains 13C-enriched carbonates without increasing the global production of oxygen

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1908783116 ◽

2019 ◽

Vol 116 (49) ◽

pp. 24433-24439 ◽

Cited By ~ 6

Author(s):

Emily C. Geyman ◽

Adam C. Maloof

Keyword(s):

Organic Carbon ◽

Carbon Cycle ◽

Shallow Water ◽

Dissolved Inorganic Carbon ◽

The Past ◽

Carbon Isotopic ◽

Oxygen Paradox ◽

Carbon Burial ◽

Continental Shelves ◽

Organic Carbon Burial

In the past 3 billion years, significant volumes of carbonate with high carbon-isotopic (δ13C) values accumulated on shallow continental shelves. These deposits frequently are interpreted as records of elevated global organic carbon burial. However, through the stoichiometry of primary production, organic carbon burial releases a proportional amount of O2, predicting unrealistic rises in atmospheric pO2 during the 1 to 100 million year-long positive δ13C excursions that punctuate the geological record. This carbon–oxygen paradox assumes that the δ13C of shallow water carbonates reflects the δ13C of global seawater-dissolved inorganic carbon (DIC). However, the δ13C of modern shallow-water carbonate sediment is higher than expected for calcite or aragonite precipitating from seawater. We explain elevated δ13C in shallow carbonates with a diurnal carbon cycle engine, where daily transfer of carbon between organic and inorganic reservoirs forces coupled changes in carbonate saturation (ΩA) and δ13C of DIC. This engine maintains a carbon-cycle hysteresis that is most amplified in shallow, sluggishly mixed waters with high rates of photosynthesis, and provides a simple mechanism for the observed δ13C-decoupling between global seawater DIC and shallow carbonate, without burying organic matter or generating O2.

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