Persistent and enhanced carbon sequestration capacity of alpine grasslands on Earth's Third Pole

Yuyang Wang; Jingfeng Xiao; Yaoming Ma; Jinzhi Ding; Xuelong Chen; Zhiyong Ding; Yiqi Luo

doi:10.1126/sciadv.ade6875

Persistent and enhanced carbon sequestration capacity of alpine grasslands on Earth's Third Pole

Sci Adv. 2023 May 19;9(20):eade6875. doi: 10.1126/sciadv.ade6875. Epub 2023 May 17.

Authors

Yuyang Wang^{1

2

3}, Jingfeng Xiao⁴, Yaoming Ma^{1

3

5

6

7}, Jinzhi Ding¹, Xuelong Chen¹, Zhiyong Ding⁸, Yiqi Luo⁹

Affiliations

¹ Land-Atmosphere Interaction and its Climatic Effects Group, State Key Laboratory of Tibetan Plateau Earth System Science, Environment and Resources (TPESER) ,, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China.
² Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
³ College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
⁴ Earth Systems Research Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH 03824, USA.
⁵ National Observation and Research Station for Qomolongma Special Atmospheric Processes and Environmental Changes, Dingri 858200, China.
⁶ Kathmandu Center of Research and Education, Chinese Academy of Sciences, Beijing 100101, China.
⁷ College of Atmospheric Science, Lanzhou University, Lanzhou 730000, China.
⁸ State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China.
⁹ School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA.

Abstract

The carbon sequestration capacity of alpine grasslands, composed of alpine meadows and steppes, in the Tibetan Plateau has an essential role in regulating the regional carbon cycle. However, inadequate understanding of its spatiotemporal dynamics and regulatory mechanisms restricts our ability to determine potential climate change impacts. We assessed the spatial and temporal patterns and mechanisms of the net ecosystem exchange (NEE) of carbon dioxide in the Tibetan Plateau. The carbon sequestration of the alpine grasslands ranged from 26.39 to 79.19 Tg C year^-1 and had an increasing rate of 1.14 Tg C year^-1 between 1982 and 2018. While alpine meadows were relatively strong carbon sinks, the semiarid and arid alpine steppes were nearly carbon neutral. Alpine meadow areas experienced strong increases in carbon sequestration mainly because of increasing temperatures, while alpine steppe areas had weak increases mainly due to increasing precipitation. Carbon sequestration capacity of alpine grasslands on the plateau has undergone persistent enhancement under a warmer and wetter climate.