Journal
AMERICAN JOURNAL OF BOTANY
Volume 106, Issue 10, Pages 1316-1326Publisher
WILEY
DOI: 10.1002/ajb2.1356
Keywords
anisohydric; drought recovery; drought tolerance; hydraulic function; isohydric; vulnerability curve
Categories
Funding
- Consejo Nacional de Ciencia y Tecnologia (CONACyT) [552210]
- Grand Challenges Initiative at Chapman University
- [CB-2014-01-238831]
Ask authors/readers for more resources
Premise Understanding plant hydraulic functioning and water balance during drought has become key in predicting species survival and recovery. However, there are few insightful studies that couple physiological and morphological attributes for many ecosystems, such as the vulnerable Tropical Montane Cloud Forests (TMCF). In this study, we evaluated drought resistance and recovery for saplings for five tree species spanning deciduous to evergreen habits from a Mexican TMCF. Methods In drought simulations, water was withheld until plants reached species-specific P-50 or P-88 values (pressures required to induce a 50 or 88% loss in hydraulic conductivity), then they were rewatered. Drought resistance was considered within the isohydric-anisohydric framework and compared to leaf gas exchange, water status, pressure-volume curves, specific leaf area, and stomatal density. Results The TMCF species closed stomata well before significant losses in hydraulic conductivity (isohydric). Yet, despite the coordination of these traits, the traits were not useful for predicting the time needed for the species to reach critical hydraulic thresholds. Instead, maximum photosynthetic rates explained these times, reinforcing the linkage between hydraulic and carbon dynamics. Despite their varying hydraulic conductivities, stomatal responses, and times to hydraulic thresholds, 58 of the 60 study plants recovered after the rewatering. The recovery of photosynthesis and stomatal conductance can be explained by the P-50 values and isohydry. Conclusions This study raises new questions surrounding drought management strategies, recovery processes, and how lethal thresholds are defined. Further studies need to consider the role of water and carbon balance in allowing for both survival and recovery from drought.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available