Beyond nitrogen: phosphorus - estimating the minimum niche dimensionality for resource competition between...

Area of Science:

• Ecology
• Limnology
• Theoretical Ecology

Background:

• Phytoplankton coexistence is often studied using nitrogen (N) and phosphorus (P) limitation.
• However, simple N and P limitation models fail to explain the high diversity observed in natural phytoplankton communities.

Discussion:

• Resource competition models were parameterized with experimental data for six phytoplankton species and nine potential limiting resources.
• Model predictions of species biomass were validated against experimental two-species mixtures.
• Uptake rates across species followed the Redfield ratio, indicating stoichiometric constraints.

Key Insights:

• Model accuracy plateaued at three to five resources, suggesting this as the minimum dimensionality for predicting coexistence.
• Models incorporating additional resources like iron (Fe), magnesium (Mg), sodium (Na), and sulfur (S) performed significantly better than N and P-only models.
• N and P limitation alone poorly predicted species biomass and community assembly.

Outlook:

• Accurate prediction of phytoplankton community assembly may require considering high-dimensional resource limitation.
• Further research should explore the complex interplay of multiple resources and stoichiometric constraints in aquatic ecosystems.
• Understanding multi-resource dynamics is crucial for ecological modeling and predicting biodiversity patterns.