Title

Differential responses of ecosystem respiration components to experimental warming in a meadow grassland on the Tibetan Plateau

Authors

Chen, J; Luo, YQ; Xia, JY; Shi, Z; Jiang, LF; Niu, SL; Zhou, XH; Cao, JJ

Abstract

Global warming is anticipated to have profound effects on terrestrial carbon fluxes and thus feed backs to future climate change. Ecosystem respiration (R_eco) is one of the dominant components of biosphere CO₂fluxes, but the effects of warming onR_ecoare still unclear. A field warming experiment using open top chambers (OTCs) was conducted in a meadow grassland on the Tibetan Plateau to study the effects of warming on the components of R_eco. Warming significantly enhanced above-ground plant respiration (R_agb) and total autotrophic plant respiration (R_plant1 by 28.7% and 19.9%, respectively, but reduced heterotrophic respiration (R_h) by 10.4%. These different responses resulted in the insensitive responses of Reco and soil respiration (R_s) to the experimental warming. The warming treatment also increased R_plant/R_ecoand R_agb/R_eco. by 8.4% and 17.3%, respectively, while decreasing R_h/R_eco, by 19.0%, suggesting that warming could eventually cause R_ecoto be dominated by R_plant. Enhancements in Roam and R_agbwere related to the warming-induced increases in aboveground biomass (AGB) while reduced R-h was closely coupled with warming-induced decrease of microbial biomass carbon. Our results highlight that the differential responses of the components of R_ecoto different environmental physics under warming scenarios should be taken into consideration to project the future carbon-climate feed backs.

Corresponding author

Cao Junji

Volume

220

Issue

Page

21-29

Pub year

April, 2016

Publication name

Agricultural and Forest Meteorology

Details

http://www.sciencedirect.com/science/article/pii/S0168192316300120