Figure 4.

Differences in substrate ¹³C utilisation in vegetated and bare soils. Mean assimilation of glucose, glycine and phenol ¹³C into RNA extracted from soil (μg¹³C μg⁻¹ RNA) (A). Glucose ¹³C incorporation was greater than the other FOC additions, although there were no consistent effects between vegetated and bare soils. Mean FOC use efficiency, displayed as the ratio of RNA ¹³C incorporation to respired substrate (RNA ¹³C:¹³CO₂-C μg g⁻¹ dry soil) (B). FOC was consistently utilised more efficiently in bare soil. Error bars are SEM (n = 3). Significant differences denoted by ^*.