The Late Miocene C<sub>4</sub> vegetation expansion and its relation with the partial pressure of carbon dioxide in atmospheric

WANG Zhen; TIAN Jun

doi:10.16562/j.cnki.0256-1492.2021032401

2021 Vol. 41, No. 5

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Article navigation > Marine Geology & Quaternary Geology > 2021 > 41(5): 160-172

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WANG Zhen, TIAN Jun. The Late Miocene C4 vegetation expansion and its relation with the partial pressure of carbon dioxide in atmospheric[J]. Marine Geology & Quaternary Geology, 2021, 41(5): 160-172. doi: 10.16562/j.cnki.0256-1492.2021032401

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WANG Zhen, TIAN Jun. The Late Miocene C₄ vegetation expansion and its relation with the partial pressure of carbon dioxide in atmospheric[J]. Marine Geology & Quaternary Geology, 2021, 41(5): 160-172. doi: 10.16562/j.cnki.0256-1492.2021032401

The Late Miocene C₄ vegetation expansion and its relation with the partial pressure of carbon dioxide in atmospheric

WANG Zhen,
TIAN Jun^,

State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China

More Information

Corresponding author: TIAN Jun, tianjun@tongji.edu.cn

Received Date: 24 March 2021

Revised Date: 12 July 2021

Publish Date: 28 October 2021

Abstract

Abstract

A large number of terrestrial and marine geological records has confirmed the global asynchronous expansion of C₄ vegetation in Late Miocene, which started in the eastern and northwestern Africa as early as 10 Ma, and then spread to South Asia, South Africa, North America and other areas in a wide range around 8～6 Ma. Finally, the C₄ vegetation expanded again in Pliocene, and the present ecological pattern is basically formed. However, the mechanism of the C₄ vegetation expansion in Late Miocene still remains unclear, with the major debate concentrating on climate and CO₂ changes. The recent atmospheric partial pressure pattern of carbon dioxide (pCO₂) reconstructed shows a downward trend of the atmospheric CO₂ concentration during Late Miocene. Considering the late Miocene C₄ vegetation expansion areas, the proxy-derived atmospheric pCO₂ is consistent with that needed for the C₄ vegetation expansion in a numerical simulation experiment, which highlights the role of the atmospheric pCO₂ in the Late Miocene C₄ vegetation expansion. The low time resolution of the existed proxy-derived atmospheric pCO₂ records determines their low reliability on both the long-term trend and the absolute values. The next step should focus on the reconstruction of the reliable high-resolution record of the atmospheric pCO₂ for Late Miocene, the key to unlock the relationship between the atmospheric pCO₂ and the C₄ vegetation expansion in Late Miocene, which has guiding significance for the study of future climate change.
- C₄ vegetation expansion /
- atmospheric pCO₂ /
- seasonal climate /
- numerical simulation /
- Late Miocene

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References

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