Drylands contribute disproportionately to observed global productivity increases

Shuai Wang; Bojie Fu; Fangli Wei; Shilong Piao; Fernando T Maestre; Lixin Wang; Wenzhe Jiao; Yanxu Liu; Yan Li; Changjia Li; Wenwu Zhao

doi:10.1016/j.scib.2023.01.014

Drylands contribute disproportionately to observed global productivity increases

Sci Bull (Beijing). 2023 Jan 30;68(2):224-232. doi: 10.1016/j.scib.2023.01.014. Epub 2023 Jan 13.

Authors

Shuai Wang¹, Bojie Fu², Fangli Wei³, Shilong Piao⁴, Fernando T Maestre⁵, Lixin Wang⁶, Wenzhe Jiao⁶, Yanxu Liu¹, Yan Li¹, Changjia Li¹, Wenwu Zhao¹

Affiliations

¹ State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China.
² State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address: bfu@rcees.ac.cn.
³ State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
⁴ Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
⁵ Department of Ecology, University of Alicante, Carretera de San Vicente del Raspeig, Alicante 03690, Spain; Multidisciplinary Institute for Environment Studies "Ramon Margalef", University of Alicante, Carretera de San Vicente del Raspeig, Alicante 03690, Spain.
⁶ Department of Earth Sciences, Indiana University-Purdue University Indianapolis, Indianapolis IN 46202, USA.

PMID: 36681590
DOI: 10.1016/j.scib.2023.01.014

Abstract

Drylands cover about 40% of the terrestrial surface and are sensitive to climate change, but their relative contributions to global vegetation greening and productivity increase in recent decades are still poorly known. Here, by integrating satellite data and biosphere modeling, we showed that drylands contributed more to global gross primary productivity (GPP) increase (65% ± 16%) than to Earth greening (33% ± 15%) observed during 1982-2015. The enhanced productivity per unit leaf area, i.e., light-use efficiency (LUE), was the mechanism behind this pattern. We also found that LUE was more sensitive to soil moisture than to atmospheric vapor pressure deficit (VPD) in drylands, while the opposite was observed (i.e., LUE was more sensitive to VPD) in humid areas. Our findings suggest the importance of using different moisture stress metrics in projecting the vegetation productivity changes of dry versus humid regions and highlight the prominent role of drylands as key controllers of the global carbon cycle.

Keywords: Disproportional changes; Earth greening; Light use efficiency; Moisture stress; The soil–plant–atmosphere continuum; Vegetation productivity increase.

Grants and funding

647038/ERC_/European Research Council/International