Response of soil C and N, dissolved organic C and N, and inorganic N to short-term experimental warming in an Alpine meadow on the Tibetan Plateau

ScientificWorldJournal. 2014:2014:152576. doi: 10.1155/2014/152576. Epub 2014 May 22.

Abstract

Although alpine meadows of Tibet are expected to be strongly affected by climatic warming, it remains unclear how soil organic C (SOC), total N (TN), ammonium N (NH4 (+)-N) , nitrate N (NO3 (+)-N), and dissolved organic C (DOC) and N (DON) respond to warming. This study aims to investigate the responses of these C and N pools to short-term experimental warming in an alpine meadow of Tibet. A warming experiment using open top chambers was conducted in an alpine meadow at three elevations (i.e., a low (4313 m), mid-(4513 m), and high (4693 m) elevation) in May 2010. Topsoil (0-20 cm depth) samples were collected in July-September 2011. Experimental warming increased soil temperature by ~1-1.4°C but decreased soil moisture by ~0.04 m(3) m(-3). Experimental warming had little effects on SOC, TN, DOC, and DON, which may be related to lower warming magnitude, the short period of warming treatment, and experimental warming-induced soil drying by decreasing soil microbial activity. Experimental warming decreased significantly inorganic N at the two lower elevations,but had negligible effect at the high elevation. Our findings suggested that the effects of short-term experimental warming on SOC, TN and dissolved organic matter were insignificant, only affecting inorganic forms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Altitude*
  • Carbon / analysis*
  • Environmental Monitoring
  • Global Warming*
  • Inorganic Chemicals / analysis*
  • Nitrogen Compounds / analysis*
  • Organic Chemicals / analysis*
  • Soil / chemistry*
  • Tibet

Substances

  • Inorganic Chemicals
  • Nitrogen Compounds
  • Organic Chemicals
  • Soil
  • Carbon