Tight stomatal regulation and high intrinsic capacity of carbon assimilation inferred from isotopic composition negatively correlate with drought-driven decline in sclerophyllous species

Key Points

• The aim is to understand how stomatal regulation and carbon assimilation affect the crown decline of sclerophyllous species during drought.
• Analyzed biochemical and diffusive limitations on photosynthesis in sclerophyllous forest species.
• Assessed the correlation between stomatal regulation and carbon assimilation capacity.
• Investigated the relationship between drought conditions and crown decline.
• Timely stomatal regulation prevents dehydration and mitigates crown decline in conjunction with high carbon assimilation capacity.
• No significant correlation was found between crown decline and levels of non-structural carbohydrates (NSC).
• Crown decline is not linked with either historical high or low growth rates of the species.