Conclusions
This study showed that the maize straw substituted for chemical
fertilizers significantly improved double-cropping rice yield by
promoting soil quality, including soil physical properties, soil enzyme
activities, microbial biomass, and soil nutrients, especially in HS
treatment. The yield of double-cropping rice was highly significantly
correlated with soil bulk density, total porosity, catalase, MBC, MBN,
and AP, and was significantly correlated with SAC and ACP, whereas there
was no significant correlation with TK. In summary, straw substituted
for chemical fertilizers is a high-yield, resource-saving and soil
improvement operation mode.