Partitioning the biodiversity effects on productivity into density and size components

Area of Science:

• Ecology
• Plant Sciences
• Biodiversity Research

Background:

• Plant density and size are critical for yield but their role in biodiversity-productivity relationships is under-examined.
• Understanding how biodiversity impacts plant survival and growth is key to ecosystem functioning.

Purpose of the Study:

• To develop a method for partitioning biodiversity effects into components related to plant density and size.
• To investigate the demographic mechanisms linking biodiversity and productivity in different plant communities.

Main Methods:

• Derivation of equations to partition net, complementarity, and selection effects of biodiversity.
• Application of the new method to empirical data from annual plant and tree diversity experiments.

Main Results:

• Overyielding in annual plants is primarily driven by selection effects increasing the size of dominant species.
• In tree communities, overyielding shifts from size-based selection to complementarity in canopy space use, reducing mortality.

Conclusions:

• The new method successfully partitions biodiversity effects, revealing distinct density and size contributions to yield.
• Demographic links between biodiversity and productivity vary significantly across ecosystems and over time.