Fig. 1From: A comparative study of ammonia-oxidizing archaea and bacteria in acidic and alkaline purple soilsAbundance of amoA and cbbL [gene encoding ribulose-1,5-biphosphate carboxylase/oxygenase (RuBisCO) pathway] in the ALK and ACI purple soil samples. The gene copy numbers were log-transformed. Error bars indicate standard deviations (n = 3). Different letters above the columns indicate significant differences (P < 0.05)Back to article page