The effects of warming-shifted plant phenology on ecosystem carbon exchange are regulated by precipitation in a semi-arid grassland

PLoS One. 2012;7(2):e32088. doi: 10.1371/journal.pone.0032088. Epub 2012 Feb 16.

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.

Methodology/principal findings: 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/significance: 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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbon Cycle*
  • Climate Change*
  • Ecosystem
  • Plant Physiological Phenomena*
  • Plants / metabolism
  • Rain*