Responses of ecosystem nitrogen cycle to nitrogen addition: a meta-analysis

New Phytol. 2011 Mar;189(4):1040-1050. doi: 10.1111/j.1469-8137.2010.03563.x. Epub 2010 Dec 7.

Abstract

• Anthropogenic nitrogen (N) addition may substantially alter the terrestrial N cycle. However, a comprehensive understanding of how the ecosystem N cycle responds to external N input remains elusive. • Here, we evaluated the central tendencies of the responses of 15 variables associated with the ecosystem N cycle to N addition, using data extracted from 206 peer-reviewed papers. • Our results showed that the largest changes in the ecosystem N cycle caused by N addition were increases in soil inorganic N leaching (461%), soil NO₃⁻ concentration (429%), nitrification (154%), nitrous oxide emission (134%), and denitrification (84%). N addition also substantially increased soil NH₄+ concentration (47%), and the N content in belowground (53%) and aboveground (44%) plant pools, leaves (24%), litter (24%) and dissolved organic N (21%). Total N content in the organic horizon (6.1%) and mineral soil (6.2%) slightly increased in response to N addition. However, N addition induced a decrease in microbial biomass N by 5.8%. • The increases in N effluxes caused by N addition were much greater than those in plant and soil pools except soil NO₃⁻, suggesting a leaky terrestrial N system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agriculture
  • Biomass
  • Ecosystem*
  • Meta-Analysis as Topic*
  • Models, Biological
  • Nitrogen / metabolism*
  • Nitrogen Cycle*

Substances

  • Nitrogen