%0 Journal Article %1 Cavender-Bares_Holbrook_01 %A Cavender-Bares, J. %A Holbrook, N. M. %D 2001 %J Plant, Cell and Environment %K bibtex-import, citeulikeExport diameter, freezebolism, papercopy, snowgumpapermaybe %P 1243--1256 %T Hydraulic properties and freezing-induced cavitation in sympatric evergreen and deciduous oak s with contrasting habitats %U http://www.blackwell-synergy.com/links/doi/10.1046/j.1365-3040.2001.00797.x %V 24 %X We investigated the hydraulic properties in relation to soil moisture, leaf habit, and phylogenetic lineage of 17 species of oaks (Quercus) that occur sympatrically in northern central Florida (USA). Leaf area per shoot increased and Huber values (ratio of sapwood area to leaf area) decreased with increasing soil moisture of species' habitats. As a result, maximum hydraulic conductance and maximum transpiration were positively correlated with mean soil moisture when calculated on a sapwood area basis, but not when calculated on a leaf area basis. This reveals the important role that changes in allometry among closely related species can play in co-ordinating water transport capacity with soil water availability. There were significant differences in specific conductivity between species, but these differences were not explained by leaf habit or by evolutionary lineage. However, white oaks had significantly smaller average vessel diameters than red oaks or live oaks. Due to their lower Huber values, maximum leaf specific conductivity (KL) was higher in evergreen species than in deciduous species and higher in live oaks than in red oaks or white oaks. There were large differences between species and between evolutionary lineages in freeze-thaw-induced embolism. Deciduous species, on average, showed greater vulnerability to freezing than evergreen species. This result is strongly influenced by evolutionary lineage. Specifically, white oaks, which are all deciduous, had significantly higher vulnerability to freezing than live oaks (all evergreen) and red oaks, which include both evergreen and deciduous species. These results highlight the importance of taking evolutionary lineage into account in comparative physiological studies.

@article{Cavender-Bares_Holbrook_01, abstract = {{We investigated the hydraulic properties in relation to soil moisture, leaf habit, and phylogenetic lineage of 17 species of oaks (Quercus) that occur sympatrically in northern central Florida (USA). Leaf area per shoot increased and Huber values (ratio of sapwood area to leaf area) decreased with increasing soil moisture of species' habitats. As a result, maximum hydraulic conductance and maximum transpiration were positively correlated with mean soil moisture when calculated on a sapwood area basis, but not when calculated on a leaf area basis. This reveals the important role that changes in allometry among closely related species can play in co-ordinating water transport capacity with soil water availability. There were significant differences in specific conductivity between species, but these differences were not explained by leaf habit or by evolutionary lineage. However, white oaks had significantly smaller average vessel diameters than red oaks or live oaks. Due to their lower Huber values, maximum leaf specific conductivity (KL) was higher in evergreen species than in deciduous species and higher in live oaks than in red oaks or white oaks. There were large differences between species and between evolutionary lineages in freeze-thaw-induced embolism. Deciduous species, on average, showed greater vulnerability to freezing than evergreen species. This result is strongly influenced by evolutionary lineage. Specifically, white oaks, which are all deciduous, had significantly higher vulnerability to freezing than live oaks (all evergreen) and red oaks, which include both evergreen and deciduous species. These results highlight the importance of taking evolutionary lineage into account in comparative physiological studies.}}, added-at = {2019-03-31T01:14:40.000+0100}, author = {Cavender-Bares, J. and Holbrook, N. M.}, biburl = {https://www.bibsonomy.org/bibtex/2cd583816b19519c14c795bf8ae10a5a0/dianella}, citeulike-article-id = {1523643}, citeulike-linkout-0 = {http://www.blackwell-synergy.com/links/doi/10.1046/j.1365-3040.2001.00797.x}, comment = {(private-note)Vessels were measured by tracing the inner perimeter of the vessel lumen and calculating the radius for a circle of the same area. Additionally, during freezing, conductivity fell to zero. (They didn't see any water uptake/ exudation?) Soil water content measured. Strange things: White oaks had significantly smaller diameter vessels than red oaks or live oaks but had highest level of freezebolism Deciduous spp showed greater vulnerability to freezebolism than evergreens. xeric spp more resistant Evergreens more resistant than deciduous also found in Cochard \& Tyree 1990, Sperry \& Sullivan 1992, Lo Cullo \& Salleo 1993, Sperry et al. 1994, Davis, Sperry \& Hacke 1999) The apparatus for freezing and conductivity measurements is interesting. And they used heat sink paste to get good thermal contact. Freezing treatment far too fast. Hydraulic mean sumr4 from Sperry et al. 1994 "it may be that by having a higher water transport capacit on a leaf area basis, a greater degree of embolism can be endured during the unfavourable season. Alternatively it may merely be a consequence of different allometry from smaller, but thicker leaves, which reduce evaporative survace area and may prevent desiccaton during the unfavourable period when water availability is often limited There was no correlation between either tranpiration on a lieaf area basis or between leaf specific conductivity and soil moisture of species' habitats. There is not a trade-off between water transport capacity and the ability to maintian foliage year-round as evergreen species actually have a higher maximum K than deciduous species. There is no relationship between PLC after freezing and hydraulically weighted vessel diameter (Fig. 8d).}, interhash = {a50feaf39c8974d5406ddd5c22b9a5c5}, intrahash = {cd583816b19519c14c795bf8ae10a5a0}, journal = {Plant, Cell and Environment}, keywords = {bibtex-import, citeulikeExport diameter, freezebolism, papercopy, snowgumpapermaybe}, pages = {1243--1256}, posted-at = {2007-07-31 06:12:43}, priority = {0}, timestamp = {2019-03-31T01:16:26.000+0100}, title = {{Hydraulic properties and freezing-induced cavitation in sympatric evergreen and deciduous oak s with contrasting habitats}}, url = {http://www.blackwell-synergy.com/links/doi/10.1046/j.1365-3040.2001.00797.x}, volume = 24, year = 2001 }