Photosynthetic and hydraulic traits influence forest resistance and resilience to drought stress across different biomes

Yanting Hu; Wenhua Xiang; Karina V R Schäfer; Pifeng Lei; Xiangwen Deng; David I Forrester; Xi Fang; Yelin Zeng; Shuai Ouyang; Liang Chen; Changhui Peng

doi:10.1016/j.scitotenv.2022.154517

Photosynthetic and hydraulic traits influence forest resistance and resilience to drought stress across different biomes

Sci Total Environ. 2022 Jul 1:828:154517. doi: 10.1016/j.scitotenv.2022.154517. Epub 2022 Mar 10.

Authors

Affiliations

¹ Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China; Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province, Huitong, China.
² Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China; Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province, Huitong, China. Electronic address: xiangwh2005@163.com.
³ Department of Earth and Environmental Sciences, Rutgers University, 195 University Avenue, Newark 07102, NJ, USA.
⁴ Swiss Federal Institute of Forest Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland.
⁵ Department of Biological Sciences, Institute of Environment Sciences, University of Quebec at Montreal, Montreal, Quebec H3C 3P8, Canada.

PMID: 35278541
DOI: 10.1016/j.scitotenv.2022.154517

Abstract

Drought events lead to depressions in gross primary productivity (GPP) of forest ecosystems. Photosynthetic and hydraulic traits are important factors governing GPP variation. However, how these functional traits affect GPP responses to drought has not been well understood. We quantified the capacity of GPP to withstand changes during droughts (GPP_resistance) and its post-drought responses (GPP_resilience) using eddy covariance data from the FLUXNET2015 dataset, and investigated how functional traits of dominant tree species that comprised >80% of the biomass (or composition) influenced GPP_resistance or GPP_resilience. Light-saturated photosynthetic rate of dominant tree species was negatively related to GPP_resistance, and was positively correlated with GPP_resilience. Forests dominated by species with higher hydraulic safety margins (HSM), smaller vessel diameter (V_dia) and lower sensitivity of canopy stomatal conductance per unit land area (G_s) to droughts had a higher GPP_resistance, while those dominated by species with lower HSM, larger V_dia and higher sensitivity of G_s to droughts exhibited a higher GPP_resilience. Differences in functional traits of forests located in diverse climate regions led to distinct GPP sensitivities to droughts. Forests located in humid regions had a higher GPP_resilience while those in arid regions exhibited a higher GPP_resistance. Forest GPP_resistance was negatively related to drought intensity, and GPP_resilience was negatively related to drought duration. Our findings highlight the significant role of functional traits in governing forest resistance and resilience to droughts. Overall, forests dominated by species with higher hydraulic safety were more resistant to droughts, while forests containing species with higher photosynthetic and hydraulic efficiency recovered better from drought stress.

Keywords: Climatic condition; Forest resilience to drought; Forest resistance to drought; Hydraulic efficiency; Hydraulic traits; Photosynthetic rate.

MeSH terms

Climate Change
Droughts*
Ecosystem*
Forests
Photosynthesis
Trees / physiology