accepted

Transpiration and stomatal control: A cross-species study of leaf traits in 39 evergreen and deciduous broadleaved subtropical tree species.

2014-10-01

2017-02-09

Kröber, W., & Bruelheide, H. (2014). Transpiration and stomatal control: a cross-species study of leaf traits in 39 evergreen and deciduous broadleaved subtropical tree species. Trees, 28(3), 901-914.

2014-10-01

Key message: Using an extensive dataset for 39 sub- tropical broadleaved tree species, we found traits of the leaf economics spectrum to be linked to mean stomatal conductance but not to stomatal regulation. The aim of our study was to establish links between stomatal control and functional leaf traits. We hypothesized that mean and maximum stomatal conduc- tance (gs) varies with the traits described by the leaf eco- nomics spectrum, such as specific leaf area and leaf dry matter content, and that high gs values correspond to species with tender leaves and high photosynthetic capacity. In addition, we hypothesized that species with leaves of low stomata density have more limited stomatal closure than those with high stomata density. In order to account for confounding site condition effects, we made use of a com- mon garden situation in which 39 deciduous and evergreen species of the same age were grown in a biodiversity eco- system functioning experiment in Jiangxi (China). Daily courses of gs were measured with porometry, and the spe- cies-specific gs*vpd relationships were modeled. Our results show that mean stomatal conductance can be pre- dicted from leaf traits that represent the leaf economics spectrum, with a positive relationship being related to leaf nitrogen content and a negative relationship with the leaf carbon: nitrogen ratio. In contrast, parameters of stomatal control were related to traits unassociated with the leaf economics spectrum. The maximum of the conduc- tance*vpd curve was positively related to leaf carbon content and vein length. The vpd at the point of inflection of the conductance*vpd curve was lower for species with higher stomata density and higher for species with a high leaf carbon content. Overall, stomata size and density as well as vein length were more effective at explaining stomatal regulation than traits used in the leaf economics spectrum.

Wenzel Kröber, Helge Bruelheide, Prof.