Soil carbon stock and its changes in northern China's grasslands from 1980s to 2000s

Yuanhe Yang, Jingyun Fang, Wenhong Ma, Pete Smith, Anwar Mohammat, Shaopeng Wang, Wei Wang

Research output: Contribution to journalArticle

138 Citations (Scopus)

Abstract

Climate warming is likely to accelerate the decomposition of soil organic carbon (SOC) which may lead to an increase of carbon release from soils, and thus provide a positive feedback to climate change. However, SOC dynamics in grassland ecosystems over the past two decades remains controversial. In this study, we estimated the magnitude of SOC stock in northern China's grasslands using 981 soil profiles surveyed from 327 sites across the northern part of the country during 2001-2005. We also examined the changes of SOC stock by comparing current measurements with historical records of 275 soil profiles derived from China's National Soil Inventory during the 1980s. Our results showed that, SOC stock in the upper 30 cm in northern China's grasslands was estimated to be 10.5 Pg C (1 Pg=1015 g), with an average density (carbon stock per area) of 5.3 kg C m-2. SOC density (SOCD) did not show significant association with mean annual temperature, but was positively correlated with mean annual precipitation. SOCD increased with soil moisture and reached a plateau when soil moisture was above 30%. Site-level comparison indicated that grassland SOC stock did not change significantly over the past two decades, with a change of 0.08 kg C m-2, ranging from -0.30 to 0.46 kg C m-2 at 95% confidence interval. Transect-scale comparison confirmed that grassland SOC stock remained relatively constant from 1980s to 2000s, suggesting that soils in northern China's grasslands have been carbon neutral over the last 20 years.

Original languageEnglish
Pages (from-to)3036-3047
Number of pages12
JournalGlobal Change Biology
Volume16
Issue number11
Early online date11 Jan 2010
DOIs
Publication statusPublished - Nov 2010

Keywords

  • alpine grasslands
  • climatic change
  • soil organic carbon
  • temperate grasslands
  • organic-carbon
  • Tibetan grasslands
  • climate-change
  • storage
  • texture
  • temperature
  • pools
  • uncertainty
  • sensitivity
  • feedbacks

Fingerprint Dive into the research topics of 'Soil carbon stock and its changes in northern China's grasslands from 1980s to 2000s'. Together they form a unique fingerprint.

  • Cite this