Articles | Volume 11, issue 13
Biogeosciences, 11, 3495–3503, 2014
Biogeosciences, 11, 3495–3503, 2014

Research article 03 Jul 2014

Research article | 03 Jul 2014

Impacts of management practices on soil organic carbon in degraded alpine meadows on the Tibetan Plateau

X. F. Chang2,1,*, X. X. Zhu4,3,*, S. P. Wang1, S. J. Cui4,3, C. Y. Luo3, Z. H. Zhang3, and A. Wilkes5 X. F. Chang et al.
  • 1Laboratory of Alpine Ecology and Biodiversity of the Institute of Tibetan Plateau Research, Chinese Academy of Sciences, 16 Lincui Rd., 100101 Beijing, China
  • 2State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, 26 Xinong Rd., 712100 Yangling, China
  • 3Key Laboratory of Adaptation and Evolution of Plateau Biota, Haibei Alpine Meadow Ecosystem Research Station, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, 23 Xinning Rd., 810008 Xining, China
  • 4Graduate University, Chinese Academy of Sciences, 19A Yuquan Rd., 100049 Beijing, China
  • 5Center for Mountain Ecosystem Studies, Kunming Institute of Botany of the Chinese Academy of Sciences, 132 Lanhei Rd., 650201 Kunming, China
  • *These authors contribued equally to this work.

Abstract. Grassland soil organic carbon (SOC) is sensitive to anthropogenic activities. Increased anthropogenic disturbance related to overgrazing has led to widespread alpine grassland degradation on the Tibetan Plateau. The degraded grasslands are considered to have great potential for carbon sequestration after adoption of improved management practices. Here, we calibrated and employed the Century model to investigate the effects of overgrazing and improved managements on the SOC dynamics in alpine meadows. We calibrated the Century model against plant productivity at the Haibei Research Station. SOC stocks for validation were obtained in 2009–2010 from degraded alpine meadows in two communes. We found that Century model can successfully capture grassland SOC changes. Overall, our simulation suggests that degraded alpine meadow SOC significantly increased with the advent of restoration management from 2011 to 2030. Carbon sequestration rates ranged between 0.04 Mg C ha−1 yr−1 in lightly degraded winter grazing grasslands and 2.0 Mg C ha−1 yr−1 in moderately degraded summer grazing grasslands. Our modelling work also predicts that improve management in degraded Tibetan grasslands will contribute to an annual carbon sink of 0.022–0.059 Pg C yr−1. These results imply that restoration of degraded grasslands in the Tibetan Plateau has great potential for soil carbon sequestration to mitigate greenhouse gases.

Final-revised paper