no significant changes in bacterial abundance versus the control
(Fig. 2A). This is similar to a report by He et al. (2007) who found
that N fertilization did not impact the total bacterial abundance in
Chinese upland red soil. Interestingly, the soil used in this
experiment has similar characteristics to that from He et al.
(2007), both are barren and acidic soils. Thus, the reproduction of
fungi may be an important reason why the yields of purified DNA
extracted from soils were greater than that in CK. This group of
microorganisms has frequently been found to benefit from mineral
N fertilization (Esperschütz et al., 2007; Ai et al., 2013). In contrast,
the three-year repeated application of commercial compost
significantly increased the abundance of bacteria.