Monitoring weekly δ 13С variations along the cambium-xylem continuum in the Canadian eastern boreal forest DOI Creative Commons
Sepideh Namvar, Étienne Boucher, Annie Deslauriers

et al.

Tree Physiology, Journal Year: 2024, Volume and Issue: 44(11)

Published: Oct. 18, 2024

Abstract Intra-annual variations of carbon stable isotope ratios (δ13C) in different tree compartments could represent valuable indicators plant source–sink dynamics, at weekly time scale. Despite this significance, the absence a methodological framework for tracking δ13C values rings persists due to complexity ring development. To fill knowledge gap, we developed method monitor variability cambium–xylem continuum black spruce species [Picea mariana (Mill.) BSP.] during growing season. We collected and isolated incremental growth cambial region developing from five mature trees over three consecutive seasons (2019–21) Simoncouche two (2020–21) Bernatchez, both located boreal forest Quebec, Canada. Our allowed creation intra-annual series cambium (δ13Ccam) xylem cellulose (δ13Cxc) these sites. Strong positive correlations were observed between δ13Ccam δ13Cxc almost all study years. These findings suggest that constant supply fresh assimilates may be dominant process feeding secondary On other hand, rates isotopic fractionation appeared poorly affected by climate variability, an inter-weekly Hence, increasing trends highlighted here possibly indicate shifts allocation strategies, likely fostering frost resistance reducing water uptake late Additionally, related trees' responses seasonal decrease photosynthetically active radiation. provide new insights into dynamics constraints ecosystems, offering novel approach studying fine temporal scales.

Language: Английский

Seasonal and Species‐Level Water‐Use Strategies and Groundwater Dependence in Dryland Riparian Woodlands During Extreme Drought DOI Creative Commons
Jared Williams, John C. Stella, Michael Bliss Singer

et al.

Water Resources Research, Journal Year: 2024, Volume and Issue: 60(4)

Published: April 1, 2024

Abstract Drought‐induced groundwater decline and warming associated with climate change are primary threats to dryland riparian woodlands. We used the extreme 2012–2019 drought in southern California as a natural experiment assess how differences water‐use strategies dependence may influence susceptibility of tree species overlapping distributions. analyzed tree‐ring stable carbon oxygen isotopes collected from two cottonwood ( Populus trichocarpa P . fremontii ) along semi‐arid Santa Clara River. also modeled source water δ 18 O composition compare observed within floodplain infer patterns reliance. Our results suggest that both functioned facultative phreatophytes shallow soil moisture when available but ultimately relied on maintain physiological function during drought. apparent related their regional was constrained more arid river segments ostensibly greater proportion satisfy higher evaporative demand. maintained ∆ 13 C at pre‐drought levels up until peak drought, trees experienced precipitous C. This response pattern suggests prioritized maintaining photosynthetic processes over hydraulic safety, critical point. In contrast, showed gradual sustained reduction C, indicating conditions induced stomatal closure use efficiency. strategy confer avoidance for while increasing its anticipated warming.

Language: Английский

Citations

1
Leaf isotopes reveal tree diversity effects on the functional responses to the pan‐European 2018 summer drought DOI
Xin Jing, Christel Baum, Bastien Castagneyrol

et al.

New Phytologist, Journal Year: 2024, Volume and Issue: 243(4), P. 1312 - 1328

Published: June 27, 2024

Recent droughts have strongly impacted forest ecosystems and are projected to increase in frequency, intensity, duration the future together with continued warming. While evidence suggests that tree diversity can regulate drought impacts natural forests, few studies examine whether mixed plantations more resistant of severe droughts. Using variations leaf carbon (C) nitrogen (N) isotopic ratios, is δ13C δ15N, as proxies for response, we analyzed effects species richness on functional responses pan-European 2018 summer seven European experiments. We found decreased increasing richness, indicating less stress. This effect was not related nor desiccation tolerance species. Leaf δ15N increased a shift toward open N cycling water availability diminishes. Additionally, intensity observed alter influence from weakly negative under low positive high intensity. Overall, our findings suggest dual isotope analysis helps understand interaction between drought, nutrients, richness.

Language: Английский

Citations

1
Trait coordination and trade-offs constrain the diversity of water use strategies in Mediterranean woody plants DOI Creative Commons
José Ignacio Querejeta, Francisco Javier Muñoz Gálvez, Iván Prieto

et al.

Research Square (Research Square), Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 14, 2024

Abstract Exploring the diversity of above and belowground water-use traits among coexisting plant species can improve understanding soil water partitioning in species-rich communities provide insights into how dryland vegetation copes with drought stress. We assessed use strategies woody at 10 Mediterranean ecosystems contrasting climatic conditions (62 total). Soil stem isotopic composition (ẟ18O, δ2H) were measured to estimate uptake depth using Bayesian mixing models, while leaf carbon oxygen isotopes (ẟ13C, Δ18O) ratio area sapwood terminal shoots used as time-integrative proxies intrinsic efficiency, stomatal conductance, investment foliage relative stems, respectively. found that distinct vertical ecohydrological niche segregation, driven by differences species, is widespread ubiquitous across all sites. Leaf-level regulation stringency efficiency also differ widely are both coordinated life forms. Within communities, larger deeper sources exhibit more conservative, water-saver level coupled greater sapwood. In contrast, smaller within same rely on shallower a profligate, water-spender strategy leaf-level lower conclude heat stress favour tight coupling coordination between multiple traits, resulting possibly unavoidable trade-offs constrain whole-plant ecologically physiologically feasible native communities.

Language: Английский

Citations

1
Water use strategies determine divergent growth trends of spruce and juniper on the southeastern Tibetan Plateau DOI Creative Commons
Lu Wang, Hongyan Liu, Liang Shi

et al.

Forest Ecosystems, Journal Year: 2024, Volume and Issue: unknown, P. 100248 - 100248

Published: Sept. 1, 2024

Language: Английский

Citations

1
Monitoring weekly δ 13С variations along the cambium-xylem continuum in the Canadian eastern boreal forest DOI Creative Commons
Sepideh Namvar, Étienne Boucher, Annie Deslauriers

et al.

Tree Physiology, Journal Year: 2024, Volume and Issue: 44(11)

Published: Oct. 18, 2024

Abstract Intra-annual variations of carbon stable isotope ratios (δ13C) in different tree compartments could represent valuable indicators plant source–sink dynamics, at weekly time scale. Despite this significance, the absence a methodological framework for tracking δ13C values rings persists due to complexity ring development. To fill knowledge gap, we developed method monitor variability cambium–xylem continuum black spruce species [Picea mariana (Mill.) BSP.] during growing season. We collected and isolated incremental growth cambial region developing from five mature trees over three consecutive seasons (2019–21) Simoncouche two (2020–21) Bernatchez, both located boreal forest Quebec, Canada. Our allowed creation intra-annual series cambium (δ13Ccam) xylem cellulose (δ13Cxc) these sites. Strong positive correlations were observed between δ13Ccam δ13Cxc almost all study years. These findings suggest that constant supply fresh assimilates may be dominant process feeding secondary On other hand, rates isotopic fractionation appeared poorly affected by climate variability, an inter-weekly Hence, increasing trends highlighted here possibly indicate shifts allocation strategies, likely fostering frost resistance reducing water uptake late Additionally, related trees' responses seasonal decrease photosynthetically active radiation. provide new insights into dynamics constraints ecosystems, offering novel approach studying fine temporal scales.

Language: Английский

Citations

1