Chin J Plan Ecolo ›› 2015, Vol. 39 ›› Issue (10): 1012-1020.DOI: 10.17521/cjpe.2015.0098

Special Issue: 生态化学计量

• Orginal Article • Previous Articles     Next Articles

Effects of external nitrogen additions on soil organic carbon dynamics and the mechanism

LI Rong1,2, CHANG Rui-Ying1,*()   

  1. 1Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
    2University of Chinese Academy of Sciences, Beijing 100049, China
  • Online:2015-10-01 Published:2015-10-24
  • Contact: Rui-Ying CHANG
  • About author:

    # Co-first authors


What would be the impact of external nitrogen additions on soil carbon, an issue still under debating, as reported experimental results were either positive, negtive or neutral. Several factors may be related to these seemingly controversial results: differences in ecosystem types and soil properties, soil carbon detection methods, soil depths, and contents of soil labile and recalcitrant carbon that affect the responses to nitrogen additions, all could cause discrepancies and variations in carbon sequestration. The several processes that contribute to enhance soil organic carbon storage include increasing litter input, decresing soil carbon output, particularly, by supressed decomposition of recalcitrant carbon, promoting soil humifiction and formation of recalcitrant carbon storage. However, there are still many uncertainties associated with these issues. To improve our understanding, the research about carbon in deep soil layers, dissolved organic carbon leaching and accumulation, and the effect of labile and recalcitrant soil C ratios on N addition responses, should be further investigated in the future studies.

Key words: external nitrogen addition, labile carbon, recalcitrant carbon, soil organic carbon sequestration, stoichemical balance