Climate change is producing changes in the rainfall regime and global temperature, lengthening and making dry periods more frequent. To better understand how forests can respond to water stress, Paula Martín Gómez, a researcher from the Forests and Water group at the Forest Science and Technology Center of Catalonia (CTFC), has published an article in Tree Physiology on the different strategies for capturing and storing water in Scots pine (Pinus sylvestris) and Portuguese oak (Quercus faginea).
The research team subjected several potted trees of each species to two drought cycles, then irrigated them with isotopically labeled water and monitored changes in their physiological behavior.
The results of the study show that these species have developed different strategies to deal with periods of scarce rainfall. On the one hand, the Scots pine has great control over its stomata, which close quickly when detecting a lack of water and reopen once the water conditions have been re-established. Thus, it has a saving behavior that allows it to protect itself from cavitation (collapse of the conductive vessels) and avoid the desiccation of leaves, branches, and trunk. Associated with this behavior, the pine generally develops more superficial root systems that take advantage of the intermittency of precipitation. On the other hand, oaks present a much more wasteful strategy with low control over their stomata, which remain open during the longest periods of drought, making them more sensitive to cavitation and tissue dehydration. Once affected by drought, it is more difficult for them to recover and that is why, in general, they develop a deep root system that guarantees more stable water sources.
“Deep knowledge of the physiological behavior of the different species will allow us to develop better forest management proposals to face future changes in climate,” explains Martín, first author of the study.
Paula Martín-Gómez, Ulises Rodríguez-Robles, Jérôme Ogée, Lisa Wingate, Domingo Sancho-Knapik, José Peguero-Pina, José Victor Santos Silva, Eustaquio Gil-Pelegrín, Jesús Pemán, Juan Pedro Ferrio, Contrasting stem water uptake and storage dynamics of water-saver and water-spender species during drought and recovery, Tree Physiology, 2023;, https://doi.org/10.1093/treephys/tpad032
Last modified: 5 May 2023