Fig. 3

Actual growth rates averaged across all N substrates (day⁻¹) (mean ± s.e.) for bacterial isolates from the eight initial N-enrichments (F _{(7, 3184)} = 36.2, P < 0.001). The N-enrichments were: Nitrate, Ammonium, Glycine, Tryptophan, Urea, Defined-N-mixture, Bacterial Protein, and Nutrient Broth. Different letters represent significantly different growth rates on each N-enrichment at P = 0.05