Evidence of field-scale shifts in transpiration dynamics following bark beetle infestation: Stomatal conductance responses

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F24%3A10481166" target="_blank" >RIV/00216208:11310/24:10481166 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=BCbtv-gpDy" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=BCbtv-gpDy</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/hyp.15162" target="_blank" >10.1002/hyp.15162</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Evidence of field-scale shifts in transpiration dynamics following bark beetle infestation: Stomatal conductance responses

Popis výsledku v původním jazyce

Amplified eruptive outbreaks of bark beetles as a consequence of climate change can cause tree mortality that significantly affects terrestrial water and carbon fluxes. However, the lack of field-scale observations of underlying physiological mechanisms currently hampers the expression of such ecosystem disturbances in predictive modelling. Based on a unique flux tower dataset from a subalpine forest located in the Rocky Mountains, mechanisms of stomatal response to an extensive bark beetle outbreak were investigated using various models and parametrizations. The datasets cover a decade, including the periods of pre-infestation, infestation, and post-infestation. Field measurements showed considerable decreases in evapotranspiration (ET), transpiration (T), and leaf area index (LAI) during the two-year infestation period compared to the pre-infestation period. Model interpretations of observed water and carbon fluxes indicated that the overall reductions in T were not solely due to decreased LAI, but also to changes in physiological behaviours. The summer season&apos;s canopy-scale stomatal conductance was significantly reduced during the infestation period, from 0.0018 to 0.0011 m s(-1). One primary reason for the observed variations is likely that the bark beetle infestation hampers the water transport in the xylem. The damage of xylem has important implications for water use efficiency (WUE), which also significantly influences the parameterization of stomatal conductance. When using stomatal conductance models to forecast ecosystem dynamics, it is crucial to recalibrate the model&apos;s parameters to ensure the accurate depiction of stomatal dynamics during various infestation periods. The neglect of the temporal variability of canopy-scale stomatal conductance under ecosystem disturbances (e.g., bark beetle infestations) in current earth system models, therefore, requires specific attention in assessments of large-scale water and carbon balances. By comparing the simulation accuracy of stomatal conductance and transpiration under an evolution-varied parameterization (considering all infestation stages) and a pre-infestation-fixed parameterization (considering undisturbed conditions) of three stomatal conductance models (Ball-Berry, Leuning, and Medlyn model), the impact of bark beetle infestation was identified. The findings highlight that the overall transpiration reduction was not only caused by reduced LAI, but also by changing physiological behaviour, which was neglected by all current models. image

Název v anglickém jazyce

Evidence of field-scale shifts in transpiration dynamics following bark beetle infestation: Stomatal conductance responses

Popis výsledku anglicky

Amplified eruptive outbreaks of bark beetles as a consequence of climate change can cause tree mortality that significantly affects terrestrial water and carbon fluxes. However, the lack of field-scale observations of underlying physiological mechanisms currently hampers the expression of such ecosystem disturbances in predictive modelling. Based on a unique flux tower dataset from a subalpine forest located in the Rocky Mountains, mechanisms of stomatal response to an extensive bark beetle outbreak were investigated using various models and parametrizations. The datasets cover a decade, including the periods of pre-infestation, infestation, and post-infestation. Field measurements showed considerable decreases in evapotranspiration (ET), transpiration (T), and leaf area index (LAI) during the two-year infestation period compared to the pre-infestation period. Model interpretations of observed water and carbon fluxes indicated that the overall reductions in T were not solely due to decreased LAI, but also to changes in physiological behaviours. The summer season&apos;s canopy-scale stomatal conductance was significantly reduced during the infestation period, from 0.0018 to 0.0011 m s(-1). One primary reason for the observed variations is likely that the bark beetle infestation hampers the water transport in the xylem. The damage of xylem has important implications for water use efficiency (WUE), which also significantly influences the parameterization of stomatal conductance. When using stomatal conductance models to forecast ecosystem dynamics, it is crucial to recalibrate the model&apos;s parameters to ensure the accurate depiction of stomatal dynamics during various infestation periods. The neglect of the temporal variability of canopy-scale stomatal conductance under ecosystem disturbances (e.g., bark beetle infestations) in current earth system models, therefore, requires specific attention in assessments of large-scale water and carbon balances. By comparing the simulation accuracy of stomatal conductance and transpiration under an evolution-varied parameterization (considering all infestation stages) and a pre-infestation-fixed parameterization (considering undisturbed conditions) of three stomatal conductance models (Ball-Berry, Leuning, and Medlyn model), the impact of bark beetle infestation was identified. The findings highlight that the overall transpiration reduction was not only caused by reduced LAI, but also by changing physiological behaviour, which was neglected by all current models. image

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10508 - Physical geography

Projekt

<a href="/cs/project/GN22-20422O" target="_blank" >GN22-20422O: Úmrtnost stromů způsobená hmyzem při změně klimatu - dopady na hydrologii a geochemii napříč měřítky</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2024

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Hydrological Processes

ISSN

0885-6087

e-ISSN

1099-1085

Svazek periodika

38

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

20

Strana od-do

e15162

Kód UT WoS článku

001226374400001

EID výsledku v databázi Scopus

2-s2.0-85193520230