Interactive comment on “ Impact of nitrogen fertilization on carbon and water fluxes in a chronosequence of three Douglas-fir stands in the Pacific Northwest ” by X

Comment #1: The Dou et al. study uses a artificial neural network (ANN) to estimate the ’control’ treatment CO2 and water fluxes of a nitrogen (N) addition experiment in a Douglas Fir chronosequence in the Pacific Northwest. The experiment was conducted in the footprint of three eddy-covariance (EC) towers meaning the scale of the experiment was much larger than most N addition experiments, and also that the use of a