Nitrogen addition increased CO(2) uptake more than non-CO(2) greenhouse gases emissions in a Moso bamboo forest

Atmospheric nitrogen (N) deposition affects the greenhouse gas (GHG) balance of ecosystems through the net atmospheric CO(2) exchange and the emission of non-CO(2) GHGs (CH(4) and N(2)O). We quantified the effects of N deposition on biomass increment, soil organic carbon (SOC), and N(2)O and CH(4) fluxes and, ultimately, the net GHG budget at ecosystem level of a Moso bamboo forest in China. Nitrogen addition significantly increased woody biomass increment and SOC decomposition, increased N(2)O emission, and reduced soil CH(4) uptake. Despite higher N(2)O and CH(4) fluxes, the ecosystem remained a net GHG sink of 26.8 to 29.4 megagrams of CO(2) equivalent hectare(−1) year(−1) after 4 years of N addition against 22.7 hectare(−1) year(−1) without N addition. The total net carbon benefits induced by atmospheric N deposition at current rates of 30 kilograms of N hectare(−1) year(−1) over Moso bamboo forests across China were estimated to be of 23.8 teragrams of CO(2) equivalent year(−1).