Plant diversity and ecosystem productivity: theoretical considerations

Area of Science:

• Ecology
• Theoretical Ecology
• Ecosystem Science

Background:

• Ecosystem processes are known to be influenced by species number and identity.
• Mathematical theory predicting these effects has been limited.

Purpose of the Study:

• To develop mathematical models predicting the relationship between biodiversity and ecosystem functioning.
• To investigate the roles of species number, identity, and resource requirements in community interactions.

Main Methods:

• Development of three simple mathematical models of interspecific competitive interactions.
• Simulation of communities with varying numbers of randomly chosen species.

Main Results:

• All models predict that ecosystem productivity increases with initial biodiversity.
• Models focusing on nutrient competition show increased nutrient retention with biodiversity.
• The impact of biodiversity on productivity and nutrient retention is amplified by greater differences in species' resource requirements.

Conclusions:

• Both species identity and biodiversity significantly influence ecosystem functioning, with their relative importance varying.
• The developed theory supports recent experimental observations on biodiversity-ecosystem functioning relationships.
• Biodiversity's effects on ecosystem functioning are explained by established ecological principles.