Variation in leaf carbon isotope discrimination inEncelia farinosa:implications for growth, competition, and drought survival

✍ Scribed by James R. Ehleringer

• Book ID: 104721567
• Publisher: Springer-Verlag
• Year: 1993
• Tongue: English
• Weight: 795 KB
• Volume: 95
• Category: Article
• ISSN: 0029-8549
• DOI: 10.1007/bf00320986

✦ Synopsis

Population-level variation in the leaf carbon isotope discrimination (Δ) values was examined in Encelia farinosa, a common Sonoran Desert shrub. There was approximately a 2‰ range in Δ values among different plants. These differences in Δ values among neighboring plants were maintained through time, both under conditions when neighbors were present and after neighbors had been removed. Individuals with high Δ values were found to have an accelerated growth rate when these plants were released from competition for water. Individuals with low Δ values were better able to persist through long-term drought. These data suggest possible tradeoffs between conditions favoring high- and low-Δ-value plants within a natural population. Given the temporal variability in precipitation between years and spatial variability in microhabitat quality in the Sonoran Desert, variation in Δ values among E. farinosa plants will be maintained within a population.