Fluxes of N2O, CH4 and soil respiration as affected by water and nitrogen addition in a temperate desert

An experiment was conducted to investigate the effect of precipitation and N deposition on N2O and CH4 fluxes and soil respiration (Rs) in the Gurbantunggut Desert from September 2014 to August 2015. The desert was a weak sink for CH4 (−0.92 kg C ha−1 yr−1) and a small source of N2O (+0.13 kg N ha−1 yr−1) and the annual rate of Rs was 874 kg C ha−1. Our work confirmed a relatively strong sink for CH4 in desert soils. Significant impacts on N2O, CH4 fluxes and Rs were found by increasing precipitation, with pulses of CH4 uptake and Rs accounting for 79.1% and 33.2% of annual CH4 uptake and Rs, respectively. N2O and CH4 fluxes were sig- nificantly enhanced by 7.8–109.6% by N addition, but it had no significant effect on Rs. Statistical significant interactions of precipitation and N addition on N2O and CH4 fluxes were found, and on Rs was lower than any single factor. Our results indicate that the Gurbantunggut Desert is a weak sink for CH4 and a small source of N2O, and is sensitive to elevated precipitation and N deposition.