Fig. 4

Critical nitrogen (N) thresholds. a Peak N content, b Critical C/N ratio, c N retention. Values are means (± SE) of the 5 replicates for the eight foliar litters in control (3 mm) and fauna exclusion treatments (0.04 mm). Asterisks denote significant (P < 0.05) differences between control (3 mm) and fauna exclusion treatments (0.04 mm). *P < 0.05, **P < 0.01