The interactive effect of no-tillage and liming on gross N transformation rates during the summer fallow in an acid Mediterranean soil

•Liming increased gross N mineralization and nitrification during the summer fallow.•No-tillage enhanced the liming effect on gross N mineralization.•N immobilization was higher in traditional tillage.•The gross N transformations and microbial indicators decreased during the summer period.•During the fallow period, NH4+, DOC and DON accumulated in all the treatments.