Variable hydraulic resistances and their impact on plant drought response modelling
Annelies Baert1, Veerle De Schepper1, Kathy Steppe2
1Laboratory of Plant Ecology, Department of Applied Ecology and Environmental Biology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, B-9000 Ghent, Belgium.
Tree Physiology
|October 3, 2014
Summary
Understanding plant drought responses is key for predicting ecosystem impacts. This study identified variable hydraulic resistances in soil and xylem as crucial mechanisms for grapevine and oak during drought.
Area of Science:
- Plant physiology
- Ecology
- Hydrology
Background:
- Plant drought responses remain incompletely understood.
- Accurate prediction of drought impacts on plants and ecosystems requires improved knowledge.
- Existing mechanistic models often fail under dry conditions due to unaddressed mechanisms.
Purpose of the Study:
- To identify key mechanisms underlying plant drought responses.
- To investigate the behavior of hydraulic resistances in soil and xylem for grapevine (Vitis vinifera L.) and oak (Quercus robur L.).
- To develop a more accurate mechanistic model for simulating plant drought responses.
Main Methods:
- Utilized mechanistic models combined with plant measurements.
- Investigated hydraulic resistances in the soil-to-stem pathway.
- Implemented a variable hydraulic soil-to-stem resistance in the model.
- Performed daily recalibration of the model.
Main Results:
- A variable hydraulic soil-to-stem resistance was necessary to accurately describe plant drought responses.
- The model generated an in situ soil-to-stem vulnerability curve.
- A drought-induced increase in radial hydraulic resistance between xylem and living tissues was observed.
Conclusions:
- Variable hydraulic resistances are critical for understanding plant drought responses.
- The developed model provides a more accurate simulation of plant water status under drought.
- Improved understanding of plant hydraulic resistances can inform ecosystem drought resilience discussions.
Keywords:
drought-induced hydraulic failuregrapevinehydraulic conductanceoakpoint dendrometerssap flowsoil conductancestem diameter variationsstem water potentialwater deficitMore Related Videos
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