As mentioned above, the
large bias of N2O fluxes measured between the DN and
the DN-CO2 methods could be ascribed to the influence
of CO2 concentration on N2O measurements for the DN
method. Considerable portions of N2O flux studies have
used the DN method (without makeup gas) and the data
obtained should be suspected (Zheng et al., 2008; Wang et
al., 2010).