Functional relationships between hydraulic traits and the timing of diurnal depression of photosynthesis
The hydraulic coordination along the water transport pathway helps trees provide adequate water supply to the canopy, ensuring that water deficits are minimized and that stomata remain open for CO2 uptake. We evaluated the stem and leaf hydraulic coordination and the linkages between hydraulic trait...
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2019
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01407791_v_n_p_Bucci http://hdl.handle.net/20.500.12110/paper_01407791_v_n_p_Bucci |
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paper:paper_01407791_v_n_p_Bucci2023-06-08T15:11:11Z Functional relationships between hydraulic traits and the timing of diurnal depression of photosynthesis Andean forests leaf hydraulic conductance leaf hydraulic vulnerability photosynthesis safety margin turgor The hydraulic coordination along the water transport pathway helps trees provide adequate water supply to the canopy, ensuring that water deficits are minimized and that stomata remain open for CO2 uptake. We evaluated the stem and leaf hydraulic coordination and the linkages between hydraulic traits and the timing of diurnal depression of photosynthesis across seven evergreen tree species in the southern Andes. There was a positive correlation between stem hydraulic conductivity (ks) and leaf hydraulic conductance (KLeaf) across species. All species had similar maximum photosynthetic rates (Amax). The species with higher ks and KLeaf attained Amax in the morning, whereas the species with lower ks and KLeaf exhibited their Amax in the early afternoon concurrently with turgor loss. These latter species had very negative leaf water potentials, but far from the pressure at which the 88% of leaf hydraulic conductance is lost. Our results suggest that diurnal gas exchange dynamics may be determined by leaf hydraulic vulnerability such that a species more vulnerable to drought restrict water loss and carbon assimilation earlier than species less vulnerable. However, under stronger drought, species with earlier CO2 uptake depression may increase the risk of hydraulic failure, as their safety margins are relatively narrow. © 2019 John Wiley & Sons Ltd 2019 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01407791_v_n_p_Bucci http://hdl.handle.net/20.500.12110/paper_01407791_v_n_p_Bucci |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Andean forests leaf hydraulic conductance leaf hydraulic vulnerability photosynthesis safety margin turgor |
| spellingShingle |
Andean forests leaf hydraulic conductance leaf hydraulic vulnerability photosynthesis safety margin turgor Functional relationships between hydraulic traits and the timing of diurnal depression of photosynthesis |
| topic_facet |
Andean forests leaf hydraulic conductance leaf hydraulic vulnerability photosynthesis safety margin turgor |
| description |
The hydraulic coordination along the water transport pathway helps trees provide adequate water supply to the canopy, ensuring that water deficits are minimized and that stomata remain open for CO2 uptake. We evaluated the stem and leaf hydraulic coordination and the linkages between hydraulic traits and the timing of diurnal depression of photosynthesis across seven evergreen tree species in the southern Andes. There was a positive correlation between stem hydraulic conductivity (ks) and leaf hydraulic conductance (KLeaf) across species. All species had similar maximum photosynthetic rates (Amax). The species with higher ks and KLeaf attained Amax in the morning, whereas the species with lower ks and KLeaf exhibited their Amax in the early afternoon concurrently with turgor loss. These latter species had very negative leaf water potentials, but far from the pressure at which the 88% of leaf hydraulic conductance is lost. Our results suggest that diurnal gas exchange dynamics may be determined by leaf hydraulic vulnerability such that a species more vulnerable to drought restrict water loss and carbon assimilation earlier than species less vulnerable. However, under stronger drought, species with earlier CO2 uptake depression may increase the risk of hydraulic failure, as their safety margins are relatively narrow. © 2019 John Wiley & Sons Ltd |
| title |
Functional relationships between hydraulic traits and the timing of diurnal depression of photosynthesis |
| title_short |
Functional relationships between hydraulic traits and the timing of diurnal depression of photosynthesis |
| title_full |
Functional relationships between hydraulic traits and the timing of diurnal depression of photosynthesis |
| title_fullStr |
Functional relationships between hydraulic traits and the timing of diurnal depression of photosynthesis |
| title_full_unstemmed |
Functional relationships between hydraulic traits and the timing of diurnal depression of photosynthesis |
| title_sort |
functional relationships between hydraulic traits and the timing of diurnal depression of photosynthesis |
| publishDate |
2019 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01407791_v_n_p_Bucci http://hdl.handle.net/20.500.12110/paper_01407791_v_n_p_Bucci |
| _version_ |
1768544033935720448 |