4. Discussion
Our results reveal that species-specific phenological firsts (leaf out and first flower) and lasts (leaf senescence and last flower) are differentially sensitive to climate warming on the cold Tibetan Plateau. Importantly, warming-induced shifts in phenological lasts and full phenological periods (growing season length and flower duration), rather than the single phenological firsts, drive changes in species dominance. Some studies have reported no relation between shifts in plant phenology and community change by solely linking phenological firsts and community coverage (McLean et al. 2016; Block et al. 2019), whereas our results can advance the understanding of the relationship between plant phenology and community by linking the phenological lasts as well as the full phenological periods with species dominance. Our results therefore stress that (1) the current trend toward observations of only the first dates of plant phenology provide an incomplete picture for assessing and predicting response of plant phenology and plant community turnover to climate warming and (2) shifts in the full phenological periods provide powerful indicators of how climatic warming alters species dominance, and by extension community structure.