Carbon and nitrogen cycle dynamics in the O-CN land surface model: 2. Role of the nitrogen cycle in the historical terrestrial carbon balance
Abstract
Global-scale results of the new O-CN terrestrial biosphere model coupling the carbon (C) and nitrogen (N) cycles show that the model produces realistic estimates of present-day C and N stocks and fluxes, despite some regional biases. N availability strongly affects high-latitude foliage area and foliage N, limiting vegetation productivity and present-day high-latitude net C uptake. Anthropogenic N deposition is predicted to have increased net primary productivity due to increases in foliage area and foliage N, contributing 0.2-0.5 Pg C yr-1 to the 1990s global net C uptake. While O-CN's modeled global 1990s terrestrial net C uptake (2.4 Pg C yr-1) is similar to the estimate not accounting for anthropogenic N inputs and N dynamics (2.6 Pg C yr-1), its latitudinal distribution and the sensitivity of the terrestrial C balance to its driving factors are substantially altered by N dynamics, with important implications for future trajectories of the global carbon cycle.
- Publication:
-
Global Biogeochemical Cycles
- Pub Date:
- March 2010
- DOI:
- 10.1029/2009GB003522
- Bibcode:
- 2010GBioC..24.1006Z
- Keywords:
-
- Biogeosciences: Biogeochemical cycles;
- processes;
- and modeling (0412;
- 0793;
- 1615;
- 4805;
- 4912);
- Biogeosciences: Carbon cycling (4806);
- Biogeosciences: Nitrogen cycling;
- Global Change: Land/atmosphere interactions (1218;
- 1843;
- 3322);
- terrestrial carbon balance;
- terrestrial biosphere modeling;
- carbon cycle;
- nitrogen cycle;
- nitrogen deposition