Alterations in temperature and precipitation regimes due to climate change threaten a number of species with mortality, especially those in Mediterranean-type ecosystems. Few studies have focused on plant hydraulic traits within a genera, but instead have tended to focus on diverse species in similar climatic conditions. Oaks are critical for ecosystem function, the economy and human health; they provide resources for many types of wildlife, lumber and food for human consumption, and regulate air quality and hydrology. This study focused on a range of physiological traits from Quercus (oak) species native to California. Studies across Quercus species have established some theory for the contribution of leaf traits to plant drought tolerance, but the evolution of drought tolerance and coordination of water use traits is not well understood. I tested relationships of leaf hydraulic conductance (Kleaf) and stomatal conductance (gs) to leaf water status, and their variation with climatic aridity for nine Quercus species grown in a common garden.
Results/Conclusions
Leaves of different Quercus species exhibit an array of responses to dehydration, correlating with the aridity of their native range. Overall, these results suggest high variability within this genus in association with climatic adaptation. A higher resolution understanding of their drought tolerance not only provides generalizable new understanding, but can also be used to inform land-managers and conservation decisions for oak habitat that faces intensified drought due to climate change.