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Climate warming, often accompanied by extreme drought events, could have profound effects on both plant community structure and ecosystem functioning. However, how warming interacts with extreme drought to affect community‐ and ecosystem‐level stability remains a largely open question. Using data from a manipulative experiment with three warming treatments in an alpine meadow that experienced one extreme drought event, we investigated how warming modulates resistance and recovery of community structural and ecosystem functional stability in facing with extreme drought. We found warming decreased resistance and recovery of aboveground net primary productivity (ANPP) and structural resistance but increased resistance and recovery of belowground net primary productivity (BNPP), overall net primary productivity (NPP), and structural recovery. The findings highlight the importance of jointly considering above‐ and belowground processes when evaluating ecosystem stability under global warming and extreme climate events. The stability of dominant species, rather than species richness and species asynchrony, was identified as a key predictor of ecosystem functional resistance and recovery, except for BNPP recovery. In addition, structural resistance of common species contributed strongly to the resistance changes in BNPP and NPP. Importantly, community structural resistance and recovery dominated the resistance and recovery of BNPP and NPP, but not for ANPP, suggesting the different mechanisms underlie the maintenance of stability of above‐ versus belowground productivity. This study is among the first to explain that warming modulates ecosystem stability in the face of extreme drought and lay stress on the need to investigate ecological stability at the community level for a more mechanistic understanding of ecosystem stability in response to climate extremes. [ABSTRACT FROM AUTHOR]

Changes in precipitation have the potential to cause dramatic changes in ecosystem carbon (C) cycling; however, it remains unclear whether different components of the net ecosystem exchange (NEE) (e.g., C uptake vs. release, plant vs. microbe respiration, above‐ground vs. below‐ground plant respiration) have similar or differential sensitivity to precipitation gradients.We conducted a manipulative field experiment (from 2015 to 2017) with six precipitation treatments, including 1/12 annual precipitation (P), 1/4 P, 1/2 P, 3/4 P, P and 5/4 P in an alpine meadow to investigate the responses of the NEE components.Over the 3 years, all C fluxes showed a nonlinear response to the precipitation gradients, except for root respiration. The most extreme drought treatment (1/12 P) caused strong reductions in NEE by 15.57%, gross primary productivity by 17.26% and ecosystem respiration by 19.05%, in contrast to the control. Plant respiration was more sensitive to precipitation change than microbe respiration, and above‐ground plant respiration was more susceptible than below‐ground respiration. Structural equation models revealed that the response of C fluxes under precipitation changes was primarily due to changes in the soil water content and above‐ground net primary productivity.Our findings indicate that future precipitation changes, particularly extreme drought, will decrease ecosystem C fluxes with different magnitudes, leading to a consequent reduction of NEE. These emergent ecosystem properties are essential for the improved elucidation of carbon cycle dynamics and benchmarking models, to predict ecosystem responses to precipitation changes. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]