Spatial aggregation and the species-area relationship across scales

Area of Science:

• Ecology
• Macroecology
• Theoretical Ecology

Background:

• Understanding species distribution is crucial for ecology.
• Relative species abundance (RSA), beta diversity, and species-area relationships (SAR) are key macroecological measures for forest plant communities.

Purpose of the Study:

• Introduce a phenomenological model to link RSA and beta diversity to SAR.
• Provide a spatially explicit framework accounting for conspecific aggregation.
• Explain the tri-phasic SAR behavior.

Main Methods:

• Developed a model based on Poisson cluster processes.
• Derived analytical expressions for SAR, endemic area relationship (EAR), and RSA scaling.
• Assumed neutral theory and considered spatial aggregation.

Main Results:

• Established an exact link between RSA, beta diversity, and SAR.
• Derived a tri-phasic SAR expression reproducible from local to continental scales.
• Provided an expression for EAR and RSA scaling.

Conclusions:

• The proposed model successfully links key macroecological measures.
• The tri-phasic SAR behavior can be explained by geometric arguments and spatial aggregation.
• The framework offers insights into species distribution patterns across scales.