Plant phenological responses to experimental warming-A synthesis

Area of Science:

• Ecology
• Plant Science
• Climate Change Biology

Background:

• Plant phenology, the timing of seasonal life cycle events, is sensitive to climate.
• Observed phenological shifts vary, complicating predictions of ecological consequences like mismatches.
• Experimental warming studies offer controlled insights into climate change impacts on plant phenology.

Purpose of the Study:

• To synthesize findings from experimental warming studies on plant phenology.
• To identify broad trends and inconsistencies in plant phenological responses to warming.
• To highlight knowledge gaps in experimental warming research.

Main Methods:

• Meta-analysis of 70 studies with 1226 observations of plant phenology under experimental warming.
• Categorization of phenological shifts by season (early vs. late) and plant type (native/nonnative, annual/perennial).
• Assessment of consistency across latitudes, elevations, habitats, and warming methods.

Main Results:

• Plants generally advance early-season phenophases (bud break, leaf-out, flowering) and delay late-season phenophases (leaf coloration, fall, senescence) under warming.
• Phenological shifts were consistent across various environmental contexts and warming methods.
• Warming effects were twice as large for nonnative annual plants compared to native perennial plants.

Conclusions:

• Experimental warming advances early plant phenology and delays late phenology, with significant impacts on nonnative annuals.
• Research gaps exist, particularly in non-temperate regions, for late-season phenophases, and for specific plant groups (woody, grasses, annuals, nonnatives).
• Future research should expand geographic scope and include diverse phenophases and plant types to improve predictive models.