Stem Hydraulic Traits are Decoupled from Leaf Ecophysiological Traits in Mangroves in Southern Philippines

The association between stem hydraulic traits and leaf functional traits in mangroves is unclear. We investigated the functional coordination between stem and leaf hydraulic traits and their integration with leaf economic spectrum (LES) in mangroves from the Sarangani Bay Protected Seascape in southern Philippines. We examined stem and leaf hydraulic traits and LES traits in 14 and 18 mangrove species, respectively, and compared them with the data on mangroves from southern China and the global plant dataset. The stem and leaf hydraulic traits were independent of each other, and they were generally decoupled from LES traits of the Philippine mangroves, which was largely attributable to leaf succulence. Mangroves from both countries had higher foliar P and K at a given leaf mass per area than the global plants. The stomatal (SD) and vein (VD) densities were not significantly correlated in the Philippine mangroves, in contrast to the strong SD-VD correlation in the Chinese mangroves and global vascular plants. This study illustrated the decoupling between hydraulic and economic leaf traits and their independence from stem hydraulic traits in mangroves in southern Philippines.