Diversity begets stability: Sublinear growth and competitive coexistence across ecosystems

Area of Science:

• Ecology
• Ecological Theory
• Macroecology

Background:

• Global species diversity loss necessitates understanding ecosystem stability.
• A long-standing debate exists between ecological theory and classic observations regarding the relationship between diversity and stability.
• Previous ecological models often predicted that increased diversity leads to decreased stability.

Purpose of the Study:

• To resolve the diversity-stability debate by proposing a new theoretical framework.
• To investigate how population growth scaling with biomass influences ecosystem stability.
• To realign ecological theory with classic observations and predict macroecological patterns.

Main Methods:

• Developed a theoretical model where population growth scales as a sublinear power law with biomass (exponent <1).
• Analyzed competitive interactions among populations exhibiting this sublinear growth.
• Compared model predictions with classic ecological observations and macroecological patterns.

Main Results:

• Sublinear growth with biomass leads to population self-regulation, analogous to individual ontogeny.
• Competitive interactions under sublinear growth do not result in exclusion but promote stability at higher diversity.
• The model successfully realigns theory with classic observations and predicts macroecological patterns.

Conclusions:

• The study resolves the diversity-stability debate by demonstrating how sublinear growth enhances stability.
• The findings suggest that biodiversity loss may accelerate ecosystem destabilization, a critical and unsettling prediction.
• This new model offers a framework for understanding large-scale ecological patterns and the consequences of biodiversity decline.