China's terrestrial ecosystem carbon balance during the 20th century: an analysis with a process-based biogeochemistry model

Yanyu Lu; Yao Huang; Qianlai Zhuang; Wei Sun; Shutao Chen; Jun Lu

doi:10.1186/s13021-022-00215-9

China's terrestrial ecosystem carbon balance during the 20th century: an analysis with a process-based biogeochemistry model

Carbon Balance Manag. 2022 Oct 8;17(1):16. doi: 10.1186/s13021-022-00215-9.

Authors

Yanyu Lu^{1

2

3}, Yao Huang⁴, Qianlai Zhuang⁵, Wei Sun⁶, Shutao Chen⁷, Jun Lu⁸

Affiliations

¹ Anhui Province Key Laboratory of Atmospheric Science and Satellite Remote Sensing, Anhui Institute of Meteorological Sciences, Hefei, China. ahqxlyy@163.com.
² Shouxian National Climatology Observatory, Huaihe River Basin Typical Farm Eco- meteorological Experiment Field of CMA, Shouxian, China. ahqxlyy@163.com.
³ College of Engineering & Natural Sciences, The University of Tulsa, Tulsa, OK, USA. ahqxlyy@163.com.
⁴ State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
⁵ Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, IN, USA.
⁶ Anhui Province Key Laboratory of Atmospheric Science and Satellite Remote Sensing, Anhui Institute of Meteorological Sciences, Hefei, China.
⁷ School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, China.
⁸ College of Engineering & Natural Sciences, The University of Tulsa, Tulsa, OK, USA.

Abstract

Background: China's terrestrial ecosystems play a pronounced role in the global carbon cycle. Here we combine spatially-explicit information on vegetation, soil, topography, climate and land use change with a process-based biogeochemistry model to quantify the responses of terrestrial carbon cycle in China during the 20th century.

Results: At a century scale, China's terrestrial ecosystems have acted as a carbon sink averaging at 96 Tg C yr^{- 1}, with large inter-annual and decadal variabilities. The regional sink has been enhanced due to the rising temperature and CO₂ concentration, with a slight increase trend in carbon sink strength along with the enhanced net primary production in the century. The areas characterized by C source are simulated to extend in the west and north of the Hu Huanyong line, while the eastern and southern regions increase their area and intensity of C sink, particularly in the late 20th century. Forest ecosystems dominate the C sink in China and are responsible for about 64% of the total sink. On the century scale, the increase in carbon sinks in China's terrestrial ecosystems is mainly contributed by rising CO₂. Afforestation and reforestation promote an increase in terrestrial carbon uptake in China from 1950s. Although climate change has generally contributed to the increase of carbon sinks in terrestrial ecosystems in China, the positive effect of climate change has been diminishing in the last decades of the 20th century.

Conclusion: This study focuses on the impacts of climate, CO₂ and land use change on the carbon cycle, and presents the potential trends of terrestrial ecosystem carbon balance in China at a century scale. While a slight increase in carbon sink strength benefits from the enhanced vegetation carbon uptake in China's terrestrial ecosystems during the 20th century, the increase trend may diminish or even change to a decrease trend under future climate change.

Keywords: Carbon cycle; China; Climate change; Hu Huanyong line; Land use; Terrestrial ecosystem Model.

Abstract

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