Figure 2.

Flexibility of nine elements in relation to each other in nine strains of freshwater heterotrophic bacteria. We define flexibility as the log₁₀[elemental content (mass/mass) at C:P of 10,000:1/ elemental content at C:P of 100:1]. Negative values represent a reduction in element quota under C:P = 10,000, zero means homeostasis, and positive values indicate that the quota increased under P-limitation. Symbols denote strains that are relatively flexible (open circles) or inflexible (closed circles) in phosphorus content. ρ = Spearman's rank coefficient.