Drought effect on plant nitrogen and phosphorus: a meta-analysis

Area of Science:

• Ecology
• Environmental Science
• Plant Physiology

Background:

• Climate change is increasing global aridity, impacting nutrient availability and plant growth.
• Plant nitrogen (N) and phosphorus (P) concentrations are key indicators of nutrient limitation.
• Understanding drought's effects on plant N and P is crucial for predicting ecosystem responses.

Purpose of the Study:

• To conduct a meta-analysis on plant N and P responses to drought.
• To examine the influence of drought duration and treatment type on plant nutrient concentrations.
• To identify key drivers of reduced plant growth under drought stress.

Main Methods:

• Meta-analysis of drought manipulation experiments.
• Quantification of plant nitrogen and phosphorus concentrations.
• Analysis of drought duration (short-term <90 days vs. long-term >90 days) and drying-rewetting cycles.

Main Results:

• Drought stress significantly decreased plant N (-3.73%) and P (-9.18%), while increasing N:P ratio (+6.98%).
• Negative effects on plant N and P were more pronounced in short-term droughts (<90 days).
• Drying-rewetting cycles mitigated negative impacts on plant N and P; constant or intermittent drought negatively affected plant P.

Conclusions:

• Extended drought duration and drying-rewetting cycles alleviate negative impacts on plant N and P.
• Water availability, not N or P, is likely the primary factor limiting plant growth during prolonged drought.
• These findings have implications for predicting vegetation responses to climate change-induced aridity.