Regional zooplankton dispersal provides spatial insurance for ecosystem function

Area of Science:

• Ecology
• Environmental Science
• Climate Change Biology

Background:

• Changing environmental conditions impact global diversity and ecosystem function.
• Dispersal may buffer local communities against disturbances by introducing functionally redundant species.
• The effectiveness of dispersal as spatial insurance may decrease over time as local communities monopolize resources.

Purpose of the Study:

• To test the spatial insurance hypothesis in zooplankton communities.
• To determine the role of dispersal timing in buffering against environmental change.
• To investigate the impact of dispersal on diversity and ecosystem function under climate change.

Main Methods:

• Field experiment with crustacean zooplankton in Churchill, Canada.
• Manipulation of nutrients, salt, and dispersal timing after disturbance.
• Assessment of diversity (species richness, evenness, Shannon-Weiner diversity) and ecosystem function (chlorophyll-a).

Main Results:

• Diversity measures were generally resistant to disturbances.
• Dispersal had the greatest impact on diversity when introduced soon after disturbance.
• Dispersal restored degraded ecosystem function (chlorophyll-a) to undisturbed levels.

Conclusions:

• Dispersal provides spatial insurance for ecosystem function, particularly when introduced early after disturbance.
• Maintaining regional diversity and habitat connectivity is crucial for future ecosystem function.
• Functionally redundant species introduced via dispersal promote compensatory dynamics essential for resilience.