A Meta-analysis of the Effects of Experimental Warming on Plant Physiology and Growth on the Tibetan Plateau

Uncertainties about the response of plant photosynthesis and growth to elevated temperature make it difficult to predict how plant production will vary under future climatic warming in alpine regions. Here, we used a meta-analysis approach to synthesize 272 observations from 27 studies on the Tibetan Plateau. Warming significantly increased aboveground biomass by 19.1 % (95 % CI 6.0-40.7 %), belowground biomass by 26.7 % (95 % CI 3.0-87.5 %), and net photosynthetic rate (P (n)) by 13.6 % (95 % CI 9.7-17.7 %). The increase of P (n) was attributed to the increases in stomatal conductance, apparent quantum yield, chlorophyll content, non-photochemical quenching of chlorophyll fluorescence, soluble sugar, and peroxidase. A decoupling of plant photosynthesis and leaf N concentration occurred. Our findings imply that global warming may have a stronger effect on the alpine plants on the Tibetan Plateau than the global average. Our findings provided a better understanding of the physiological responses of alpine plants to future climatic warming.