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Smith IA, Templer PH, Hutyra LR. Water sources for street trees in mesic urban environments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168411. [PMID: 37939949 DOI: 10.1016/j.scitotenv.2023.168411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 10/20/2023] [Accepted: 11/05/2023] [Indexed: 11/10/2023]
Abstract
Street trees support climate resiliency through a variety of pathways, such as offsetting urban heat and attenuating storm water runoff. While urban trees in arid and semiarid ecosystems have been shown to take up water from irrigation, it is unknown where street trees in mesic cities obtain their water. In this study, we use natural abundance stable isotopes to estimate the proportional sources of water taken up by Acer platanoides street trees in Boston, Massachusetts, United States, including precipitation, irrigation, groundwater, and wastewater. We use Bayesian multisource mixing models to estimate water sources by comparing the natural abundance isotopic ratios of hydrogen and oxygen across potential water sources with water extracted from tree stem samples. We find that during the summer of 2021, characterized by anomalously high rainfall, street trees predominantly utilized water from precipitation. Precipitation accounted for 72.3 % of water extracted from trees sampled in August and 65.6 % from trees sampled in September. Of the precipitation taken up by street trees, most water was traced back to large storm events in July, with July rainfall alone accounting for up to 84.0 % of water found within street trees. We find strong relationships between canopy cover fractions and the proportion of precipitation lost to evapotranspiration across the study domain, supporting the conclusion that tree planting initiatives result in storm water mitigation benefits due to utilization of water from precipitation by urban vegetation. However, while the mature trees studied here currently support their water demand from precipitation, the dependency of street trees on precipitation in mesic cities may lead to increased water stress in a changing climate characterized by a higher frequency and severity of drought.
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Affiliation(s)
- Ian A Smith
- Boston University, Department of Earth & Environment, 685 Commonwealth Ave., Boston, MA 02215, USA.
| | - Pamela H Templer
- Boston University, Department of Biology, 5 Cummington Mall, Boston, MA 02215, USA
| | - Lucy R Hutyra
- Boston University, Department of Earth & Environment, 685 Commonwealth Ave., Boston, MA 02215, USA
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2
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Yin Y, He L, Wennberg PO, Frankenberg C. Unequal exposure to heatwaves in Los Angeles: Impact of uneven green spaces. SCIENCE ADVANCES 2023; 9:eade8501. [PMID: 37115921 PMCID: PMC10146884 DOI: 10.1126/sciadv.ade8501] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Cities worldwide are experiencing record-breaking summer temperatures. Urban environments exacerbate extreme heat, resulting in not only the urban heat island but also intracity variations in heat exposure. Understanding these disparities is crucial to support equitable climate mitigation and adaptation efforts. We found persistent negative correlations between daytime land surface temperature (LST) and median household income across the Los Angeles metropolitan area based on Ecosystem Spaceborne Thermal Radiometer Experiment on Space Station observations from 2018 to 2021. Lower evapotranspiration resulting from the unequal distribution of vegetation cover is a major factor leading to higher LST in low-income neighborhoods. Disparities worsen with higher regional mean surface temperature, with a $10,000 decrease in income leading to ~0.2°C LST increase at 20°C and up to ~0.7°C at 45°C. With more frequent and intense heat waves projected in the future, equitable mitigation measures, such as increasing surface albedo and tree cover in low-income neighborhoods, are necessary to address these disparities.
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Affiliation(s)
- Yi Yin
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
- Corresponding author.
| | - Liyin He
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
| | - Paul O. Wennberg
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, USA
| | - Christian Frankenberg
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
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3
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Ibsen PC, Santiago LS, Shiflett SA, Chandler M, Jenerette GD. Irrigated urban trees exhibit greater functional trait plasticity compared to natural stands. Biol Lett 2023; 19:20220448. [PMID: 36596464 PMCID: PMC9810417 DOI: 10.1098/rsbl.2022.0448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Urbanization creates novel ecosystems comprised of species assemblages and environments with no natural analogue. Moreover, irrigation can alter plant function compared to non-irrigated systems. However, the capacity of irrigation to alter functional trait patterns across multiple species is unknown but may be important for the dynamics of urban ecosystems. We evaluated the hypothesis that urban irrigation influences plasticity in functional traits by measuring carbon-gain and water-use traits of 30 tree species planted in Southern California, USA spanning a coastal-to-desert gradient. Tree species respond to irrigation through increasing the carbon-gain trait relationship of leaf nitrogen per specific leaf area compared to their native habitat. Moreover, most species shift to a water-use strategy of greater water loss through stomata when planted in irrigated desert-like environments compared to coastal environments, implying that irrigated species capitalize on increased water availability to cool their leaves in extreme heat and high evaporative demand conditions. Therefore, irrigated urban environments increase the plasticity of trait responses compared to native ecosystems, allowing for novel response to climatic variation. Our results indicate that trees grown in water-resource-rich urban ecosystems can alter their functional traits plasticity beyond those measured in native ecosystems, which can lead to plant trait dynamics with no natural analogue.
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Affiliation(s)
- Peter C. Ibsen
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA 92521, USA,Geosciences and Environmental Change Science Center, United States Geological Survey, Denver, CO 80225, USA
| | - Louis S. Santiago
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA 92521, USA
| | - Sheri A. Shiflett
- Department of Environmental Sciences, University of North Carolina Wilmington, Wilmington, NC 28403, USA
| | | | - G. Darrel Jenerette
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA 92521, USA
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Ibsen PC, Jenerette GD, Dell T, Bagstad KJ, Diffendorfer JE. Urban landcover differentially drives day and nighttime air temperature across a semi-arid city. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 829:154589. [PMID: 35306078 DOI: 10.1016/j.scitotenv.2022.154589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 03/11/2022] [Accepted: 03/11/2022] [Indexed: 06/14/2023]
Abstract
Semi-arid urban environments are undergoing an increase in both average air temperatures and in the frequency and intensity of extreme heat events. Within cities, different composition and densities of urban landcovers (ULC) influence local air temperatures, either mitigating or increasing heat. Currently, understanding how combinations of ULC influence air temperature at the block to neighborhood scale is necessary for heat mitigation plans, and yet limited due to the complexities integrating high-resolution ULC with spatial and temporally high-resolution microclimate data. We quantify how ULC influences air temperature at 60 m resolution for day and nighttime climate normals and extreme heat conditions by integrating microclimate sensor data sensor and high-resolution (1 m2) ULC for Denver, Colorado's urban core. We derive ULC drivers of air temperature using a structural equation model, then use a random forest algorithm to predict air temperatures for 30-year climate normals and an extreme heat condition. We find that, in conjunction with other ULC, urban tree canopy reduces daytime air temperatures (-0.026 °C per % cover), and the combination of impervious surfaces and buildings increases daytime air temperature (0.021 °C per % cover). Compared to daytime hours, nighttime irrigated turf temperature cooling effects are increased from being non-significant to -0.022 °C per % cover, while tree canopy effects are reduced from -0.026 °C during the day to -0.016 °C at night. Overall, ULC drives ~17% and 25% of local air temperature during the day and night, respectively. ULC influence on daytime air temperatures is altered in extreme heat events, both depending on the ULC type and time of day. Our findings inform urban planners seeking to identify potential hot and cool spots within a semi-arid city and mitigate high urban air temperatures through using ULC within larger urban climate mitigation strategies.
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Affiliation(s)
- Peter C Ibsen
- U.S. Geological Survey, Geosciences & Environmental Change Science Center, Denver, CO 80225, United States.
| | - G Darrel Jenerette
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA 92507, United States
| | - Tyler Dell
- Civil and Environmental Engineering, Colorado State University, Fort Collins, CO 80523, United States
| | - Kenneth J Bagstad
- U.S. Geological Survey, Geosciences & Environmental Change Science Center, Denver, CO 80225, United States
| | - Jay E Diffendorfer
- U.S. Geological Survey, Geosciences & Environmental Change Science Center, Denver, CO 80225, United States
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Smith IA, Winbourne JB, Tieskens KF, Jones TS, Bromley FL, Li D, Hutyra LR. A Satellite-Based Model for Estimating Latent Heat Flux From Urban Vegetation. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.695995] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The impacts of extreme heat events are amplified in cities due to unique urban thermal properties. Urban greenspace mitigates high temperatures through evapotranspiration and shading; however, quantification of vegetative cooling potential in cities is often limited to simple remote sensing greenness indices or sparse, in situ measurements. Here, we develop a spatially explicit, high-resolution model of urban latent heat flux from vegetation. The model iterates through three core equations that consider urban climatological and physiological characteristics, producing estimates of latent heat flux at 30-m spatial resolution and hourly temporal resolution. We find strong agreement between field observations and model estimates of latent heat flux across a range of ecosystem types, including cities. This model introduces a valuable tool to quantify the spatial heterogeneity of vegetation cooling benefits across the complex landscape of cities at an adequate resolution to inform policies addressing the effects of extreme heat events.
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Winbourne JB, Jones TS, Garvey SM, Harrison JL, Wang L, Li D, Templer PH, Hutyra LR. Tree Transpiration and Urban Temperatures: Current Understanding, Implications, and Future Research Directions. Bioscience 2020. [DOI: 10.1093/biosci/biaa055] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
The expansion of an urban tree canopy is a commonly proposed nature-based solution to combat excess urban heat. The influence trees have on urban climates via shading is driven by the morphological characteristics of trees, whereas tree transpiration is predominantly a physiological process dependent on environmental conditions and the built environment. The heterogeneous nature of urban landscapes, unique tree species assemblages, and land management decisions make it difficult to predict the magnitude and direction of cooling by transpiration. In the present article, we synthesize the emerging literature on the mechanistic controls on urban tree transpiration. We present a case study that illustrates the relationship between transpiration (using sap flow data) and urban temperatures. We examine the potential feedbacks among urban canopy, the built environment, and climate with a focus on extreme heat events. Finally, we present modeled data demonstrating the influence of transpiration on temperatures with shifts in canopy extent and irrigation during a heat wave.
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Affiliation(s)
| | | | | | - Jamie L Harrison
- Department of Biology at Boston University, Boston, Massachusetts
| | | | - Dan Li
- Department of Earth and Environment
| | - Pamela H Templer
- Department of Biology at Boston University, Boston, Massachusetts
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Inferring the source of evaporated waters using stable H and O isotopes. Oecologia 2018; 187:1025-1039. [PMID: 29955987 DOI: 10.1007/s00442-018-4192-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 06/05/2018] [Indexed: 10/28/2022]
Abstract
Stable isotope ratios of H and O are widely used to identify the source of water, e.g., in aquifers, river runoff, soils, plant xylem, and plant-based beverages. In situations where the sampled water is partially evaporated, its isotope values will have evolved along an evaporation line (EL) in δ2H/δ18O space, and back-correction along the EL to its intersection with a meteoric water line (MWL) has been used to estimate the source water's isotope ratios. Here, we review the theory underlying isotopic estimation of source water for evaporated samples (iSWE). We note potential for bias from a commonly used regression-based approach for EL slope estimation and suggest that a model-based approach may be preferable if assumptions of the regression approach are not valid. We then introduce a mathematical framework that eliminates the need to explicitly estimate the EL-MWL intersection, simplifying iSWE analysis and facilitating more rigorous uncertainty estimation. We apply this approach to data from the US EPA's 2007 National Lakes Assessment. We find that data for most lakes are consistent with a water source similar to annual runoff, estimated from monthly precipitation and evaporation within the lake basin. Strong evidence for both summer- and winter-biased sources exists, however, with winter bias pervasive in most snow-prone regions. The new analytical framework should improve the rigor of iSWE in ecohydrology and related sciences, and our initial results from US lakes suggest that previous interpretations of lakes as unbiased isotope integrators may only be valid in certain climate regimes.
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Gotsch SG, Draguljić D, Williams CJ. Evaluating the effectiveness of urban trees to mitigate storm water runoff via transpiration and stemflow. Urban Ecosyst 2017. [DOI: 10.1007/s11252-017-0693-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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9
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Variation in urban forest productivity and response to extreme drought across a large metropolitan region. Urban Ecosyst 2017. [DOI: 10.1007/s11252-017-0692-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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10
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Evaristo J, McDonnell JJ. Prevalence and magnitude of groundwater use by vegetation: a global stable isotope meta-analysis. Sci Rep 2017; 7:44110. [PMID: 28281644 PMCID: PMC5345103 DOI: 10.1038/srep44110] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 02/02/2017] [Indexed: 11/09/2022] Open
Abstract
The role of groundwater as a resource in sustaining terrestrial vegetation is widely recognized. But the global prevalence and magnitude of groundwater use by vegetation is unknown. Here we perform a meta-analysis of plant xylem water stable isotope (δ2H and δ18O, n = 7367) information from 138 published papers - representing 251 genera, and 414 species of angiosperms (n = 376) and gymnosperms (n = 38). We show that the prevalence of groundwater use by vegetation (defined as the number of samples out of a universe of plant samples reported to have groundwater contribution to xylem water) is 37% (95% confidence interval, 28-46%). This is across 162 sites and 12 terrestrial biomes (89% of heterogeneity explained; Q-value = 1235; P < 0.0001). However, the magnitude of groundwater source contribution to the xylem water mixture (defined as the proportion of groundwater contribution in xylem water) is limited to 23% (95% CI, 20-26%; 95% prediction interval, 3-77%). Spatial analysis shows that the magnitude of groundwater source contribution increases with aridity. Our results suggest that while groundwater influence is globally prevalent, its proportional contribution to the total terrestrial transpiration is limited.
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Affiliation(s)
- Jaivime Evaristo
- Global Institute for Water Security and School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Canada
| | - Jeffrey J. McDonnell
- Global Institute for Water Security and School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Canada
- School of Geosciences, University of Aberdeen, Aberdeen, Scotland, United Kingdom
- Department of Forest Engineering, Resources and Management, Oregon State University, Corvallis, Oregon 97330 USA
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11
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Urban Heat Stress Vulnerability in the U.S. Southwest: The Role of Sociotechnical Systems. SUSTAINABILITY 2016. [DOI: 10.3390/su8090842] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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12
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Evaristo J, Jasechko S, McDonnell JJ. Global separation of plant transpiration from groundwater and streamflow. Nature 2015; 525:91-4. [PMID: 26333467 DOI: 10.1038/nature14983] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Accepted: 07/14/2015] [Indexed: 11/09/2022]
Abstract
Current land surface models assume that groundwater, streamflow and plant transpiration are all sourced and mediated by the same well mixed water reservoir--the soil. However, recent work in Oregon and Mexico has shown evidence of ecohydrological separation, whereby different subsurface compartmentalized pools of water supply either plant transpiration fluxes or the combined fluxes of groundwater and streamflow. These findings have not yet been widely tested. Here we use hydrogen and oxygen isotopic data ((2)H/(1)H (δ(2)H) and (18)O/(16)O (δ(18)O)) from 47 globally distributed sites to show that ecohydrological separation is widespread across different biomes. Precipitation, stream water and groundwater from each site plot approximately along the δ(2)H/δ(18)O slope of local precipitation inputs. But soil and plant xylem waters extracted from the 47 sites all plot below the local stream water and groundwater on the meteoric water line, suggesting that plants use soil water that does not itself contribute to groundwater recharge or streamflow. Our results further show that, at 80% of the sites, the precipitation that supplies groundwater recharge and streamflow is different from the water that supplies parts of soil water recharge and plant transpiration. The ubiquity of subsurface water compartmentalization found here, and the segregation of storm types relative to hydrological and ecological fluxes, may be used to improve numerical simulations of runoff generation, stream water transit time and evaporation-transpiration partitioning. Future land surface model parameterizations should be closely examined for how vegetation, groundwater recharge and streamflow are assumed to be coupled.
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Affiliation(s)
- Jaivime Evaristo
- Global Institute for Water Security and School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Saskatchewan S7N 3H5, Canada
| | - Scott Jasechko
- Department of Geography, University of Calgary, Calgary, Alberta T2N IN4, Canada
| | - Jeffrey J McDonnell
- Global Institute for Water Security and School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Saskatchewan S7N 3H5, Canada.,School of Geosciences, University of Aberdeen, Aberdeen AB34 3FX, UK.,Department of Forest Engineering, Resources and Management, Oregon State University, Corvallis, Oregon 97331, USA
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Pataki DE, McCarthy HR, Gillespie T, Jenerette GD, Pincetl S. A trait‐based ecology of the Los Angeles urban forest. Ecosphere 2013. [DOI: 10.1890/es13-00017.1] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- D. E. Pataki
- Department of Biology, University of Utah, Salt Lake City, Utah 84112 USA
| | - H. R. McCarthy
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma 731019 USA
| | - T. Gillespie
- Department of Geography, University of California, Los Angeles, California 90095 USA
| | - G. D. Jenerette
- Department of Botany and Plant Sciences, University of California, Riverside, California 92521 USA
| | - S. Pincetl
- Institute of the Environment and Sustainability, University of California, Los Angeles, California 90095 USA
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Kim ST, Park SS, Yun ST. Influence of dissolved ions on determination of oxygen isotope composition of aqueous solutions using the CO2-H2O equilibration method. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2012; 26:2083-2092. [PMID: 22847709 DOI: 10.1002/rcm.6323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
RATIONALE Stable isotope compositions of natural waters, such as seawater, glaciers and basinal brines, can provide valuable information about Earth's hydrological cycle and its evolutionary history. However, a high concentration of dissolved ions in some natural waters hinders an accurate analysis of their oxygen isotope composition. A laboratory study was carried out in order to provide guidelines on how to resolve this analytical difficulty. METHODS CO(2) gas was equilibrated with saline aqueous solutions of various chemical compositions at 25 °C. Subsequently, the oxygen isotope composition of the CO(2) was determined at different equilibration times using a dual-inlet isotope ratio mass spectrometer in order to evaluate the oxygen isotope salt effect and the rate of oxygen isotope exchange between CO(2) and the saline solution. RESULTS Using the experimentally determined oxygen isotope salt effects of aqueous chloride and sulfate solutions, an empirical method for the prediction of the oxygen isotope salt effect of a 1.0 molal chloride or sulfate solution was proposed. The rates of oxygen isotope exchange between CO(2) and saline solutions were also examined. Our experimental data indicates that the sequence of the oxygen isotope exchange time is as: MgSO(4) > CaCl(2) ≈ Na(2)SO(4) > NaCl > MgCl(2) > KCl > H(2)O. CONCLUSIONS The isotope salt effect and the kinetics of isotope exchange must be taken into account when the oxygen isotope composition of a saline aqueous solution is determined using the CO(2)-H(2)O equilibration method. Our experimental data and the proposed prediction method provide essential guidelines for the accurate δ(18)O analysis of saline aqueous solutions.
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Affiliation(s)
- Sang-Tae Kim
- School of Geography and Earth Sciences, McMaster University, 1280 Main Street West, Hamilton, ON, Canada L8S 4K1.
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Litvak E, McCarthy HR, Pataki DE. Transpiration sensitivity of urban trees in a semi-arid climate is constrained by xylem vulnerability to cavitation. TREE PHYSIOLOGY 2012; 32:373-88. [PMID: 22447283 DOI: 10.1093/treephys/tps015] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Establishing quantitative links between plant hydraulic properties and the response of transpiration to environmental factors such as atmospheric vapor pressure deficit (D) is essential for improving our ability to understand plant water relations across a wide range of species and environmental conditions. We studied stomatal responses to D in irrigated trees in the urban landscape of Los Angeles, California. We found a strong linear relationship between the sensitivity of tree-level transpiration estimated from sap flux (m(T); slope of the relationship between tree transpiration and ln D) and transpiration at D=1 kPa (E(Tref)) that was similar to previous surveys of stomatal behavior in natural environments. In addition, m(T) was significantly related to vulnerability to cavitation of branches (P(50)). While m(T) did not appear to differ between ring- and diffuse-porous species, the relationship between m(T) and P(50) was distinct by wood anatomy. Therefore, our study confirms systematic differences in water relations in ring- versus diffuse-porous species, but these differences appear to be more strongly related to the relationship between stomatal sensitivity to D and vulnerability to cavitation rather than to stomatal sensitivity per se.
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Affiliation(s)
- Elizaveta Litvak
- Department of Earth System Science, University of California, Irvine, CA 92697, USA.
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