Increased N fertilization also tended to increase native SOC decomposition, but a significant increase was observed only for the C0 level
(C0N2≈C0N1NC0N0) in this study (Fig. 6a,p= 0.065): the cumulative PE difference (N2−N0) was 19% of C0N0 SOC decomposition,
and at C5 straw rate, thisfigure was 8% (Table 3). Increased rates of N
fertilization significantly (p= 0.005) increased the newly formed SOC
from maize straw amendment. The interactive effect of maize straw
amendment and N fertilization was highly significant (pb0.001), indicating that the effect of N fertilization on SOC accrual tended to be more
pronounced at increased levels of maize straw amendment (C3 and C5,
Fig. 6a)