Fig. 4
Phospholipid fatty acids (PLFAs, mean ± standard error) at 0–10 cm depth under various tillage and organic matter (OM) input practices. NT, no-tillage; ET, earthworm bio-tillage; RT, traditional rotary tillage; None, without OM input; Straw, straw return; CM, cow manure addition. G+, gram-positive bacteria; G-, gram-negative bacteria; F/B, the ratio of fungi to bacteria; G+/G-, the ratio of G + to G-. Different uppercase letters indicate significant differences between tillage practices under the same OM input (n = 4, p < 0.05). Different lowercase letters indicate significant differences between OM inputs under the same tillage treatment (n = 4, p < 0.05).
