title: The effects of warming-shifted plant phenology on ecosystem carbon exchange are regulated by precipitation in a semi-arid grassland.
abstract: BACKGROUND
  The longer growing season under climate warming has served as a crucial mechanism for the enhancement of terrestrial carbon (C) sink over the past decades. A better understanding of this mechanism is critical for projection of changes in C cycling of terrestrial ecosystems.
  
  
  RESULTS
  A 4-year field experiment with day and night warming was conducted to examine the responses of plant phenology and their influences on plant coverage and ecosystem C cycling in a temperate steppe in northern China. Greater phenological responses were observed under night than day warming. Both day and night warming prolonged the growing season by advancing phenology of early-blooming species but without changing that of late-blooming species. However, no warming response of vegetation coverage was found for any of the eight species. The variances in species-level coverage and ecosystem C fluxes under different treatments were positively dependent upon the accumulated precipitation within phenological duration but not the length of phenological duration.
  
  
  CONCLUSIONS
  These plants' phenology is more sensitive to night than day warming, and the warming effects on ecosystem C exchange via shifting plant phenology could be mediated by precipitation patterns in semi-arid grasslands.
authors.affiliation: State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, The Chinese Academy of Sciences, Xiangshan, Beijing, China.
authors.forename: Jianyang
authors.initials: J
authors.lastname: Xia
authors.forename: Shiqiang
authors.initials: S
authors.lastname: Wan
mesh_terms: D057486:Carbon Cycle; D057231:Climate Change; D017753:Ecosystem; D018521:Plant Physiological Phenomena; D010944:Plants / Q000378:metabolism; D011891:Rain