Planktonic functional diversity changes in synchrony with lake ecosystem state.

Area of Science:

• Ecology
• Biodiversity Science
• Ecosystem Management

Background:

• Effective ecosystem management relies on tools to monitor stability and dynamics.
• Functional diversity (FD) is proposed as a sensitive biodiversity metric influencing ecological processes.
• The temporal relationship between FD changes and ecosystem state shifts remains unclear.

Purpose of the Study:

• To investigate the lagged temporal relationship between planktonic functional diversity and ecosystem state metrics.
• To determine if functional diversity changes precede or follow changes in ecosystem state (e.g., biomass).
• To assess the potential of functional diversity as an early indicator of ecosystem change.

Main Methods:

• Analysis of lagged relationships between planktonic functional diversity and abundance-based ecosystem state metrics.
• Utilized correlation and non-linear empirical dynamic modeling approaches.
• Studied five highly monitored lake communities.

Main Results:

• Phytoplankton and zooplankton functional diversity showed synchrony with lake ecosystem state.
• The strength of the relationship between FD and ecosystem state varied significantly among lakes (idiosyncratic).
• Functional diversity changes were unlikely to be detectable before changes in more easily measured abundance metrics.

Conclusions:

• Functional diversity is unlikely to be a universally applicable early warning indicator for ecosystem state changes.
• Ecosystem-specific contexts are crucial for interpreting functional diversity metrics.
• Functional diversity remains valuable as an alternative measure of ecosystem state or a trait-based representation of biodiversity at the system level.