Effect of elevated CO2 concentration and vapour pressure deficit on isoprene emission from leaves of Populus deltoides during drought

To further our understanding of the influence of global climate change on isoprene production we studied the effect of elevated [CO2] and vapour pressure deficit (VPD) on isoprene emission rates from leaves of Populus deltoides Bartr. during drought stress. Trees, grown inside three large bays with atmospheres containing 430, 800, or 1200 μmol mol–1 CO2 at the Biosphere 2 facility, were subjected to a period of drought during which VPD was manipulated, switching between low VPD (approximately 1 kPa) and high VPD (approximately 3 kPa) for several days. When trees were not water-stressed, elevated [CO2] inhibited isoprene emission and stimulated photosynthesis. Isoprene emission was less responsive to drought than photosynthesis. As water-stress increased, the inhibition of isoprene emission disappeared, probably as a result of stomatal closure and the resulting decreases in intercellular [CO2] (Ci). This assumption was supported by increased isoprene emission under high VPD. Drought and high VPD dramatically increased the proportion of assimilated carbon lost as isoprene. When measured at the same [CO2], leaves from trees grown at ambient [CO2] always had higher isoprene emission rates than the leaves of trees grown at elevated [CO2], demonstrating that CO2 inhibition is a long-term effect.

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Effects of drought and changes in vapour pressure deficit on water relations of Populus deltoides growing in ambient and elevated CO2

Tree Physiology ◽

10.1093/treephys/tpq036 ◽

2010 ◽

Vol 30 (7) ◽

pp. 866-875 ◽

Cited By ~ 21

Author(s):

E. G. Bobich ◽

G. A. Barron-Gafford ◽

K. G. Rascher ◽

R. Murthy

Keyword(s):

Elevated Co2 ◽

Water Relations ◽

Vapour Pressure ◽

Populus Deltoides ◽

Vapour Pressure Deficit ◽

Effects Of Drought

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Photosynthesis and Related Physiological Parameters Differences Affected the Isoprene Emission Rate among 10 Typical Tree Species in Subtropical Metropolises

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18030954 ◽

2021 ◽

Vol 18 (3) ◽

pp. 954

Author(s):

Junyao Lyu ◽

Feng Xiong ◽

Ningxiao Sun ◽

Yiheng Li ◽

Chunjiang Liu ◽

...

Keyword(s):

Photosynthetic Rate ◽

Tree Species ◽

Urban Areas ◽

Emission Rate ◽

Intercellular Co2 Concentration ◽

Co2 Concentration ◽

Single Species ◽

Photosynthetic Parameters ◽

Emission Rates ◽

Isoprene Emission

Volatile organic compound (VOCs) emission is an important cause of photochemical smog and particulate pollution in urban areas, and urban vegetation has been presented as an important source. Different tree species have different emission levels, so adjusting greening species collocation is an effective way to control biogenic VOC pollution. However, there is a lack of measurements of tree species emission in subtropical metropolises, and the factors influencing the species-specific differences need to be further clarified. This study applied an in situ method to investigate the isoprene emission rates of 10 typical tree species in subtropical metropolises. Photosynthesis and related parameters including photosynthetic rate, intercellular CO2 concentration, stomatal conductance, and transpiration rate, which can influence the emission rate of a single species, were also measured. Results showed Salix babylonica always exhibited a high emission level, whereas Elaeocarpus decipiens and Ligustrum lucidum maintained a low level throughout the year. Differences in photosynthetic rate and stomatal CO2 conductance are the key parameters related to isoprene emission among different plants. Through the establishment of emission inventory and determination of key photosynthetic parameters, the results provide a reference for the selection of urban greening species, as well as seasonal pollution control, and help to alleviate VOC pollution caused by urban forests.

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Increasing leaf temperature reduces the suppression of isoprene emission by elevated CO2 concentration

The Science of The Total Environment ◽

10.1016/j.scitotenv.2014.02.065 ◽

2014 ◽

Vol 481 ◽

pp. 352-359 ◽

Cited By ~ 14

Author(s):

Mark J. Potosnak ◽

Lauren LeStourgeon ◽

Othon Nunez

Keyword(s):

Elevated Co2 ◽

Co2 Concentration ◽

Leaf Temperature ◽

Elevated Co2 Concentration ◽

Isoprene Emission

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Isoprene emissions from a tundra ecosystem

Biogeosciences ◽

10.5194/bg-10-871-2013 ◽

2013 ◽

Vol 10 (2) ◽

pp. 871-889 ◽

Cited By ~ 32

Author(s):

M. J. Potosnak ◽

B. M. Baker ◽

L. LeStourgeon ◽

S. M. Disher ◽

K. L. Griffin ◽

...

Keyword(s):

Atmospheric Chemistry ◽

Global Climate ◽

Common Species ◽

Emission Rates ◽

Arctic Ecosystems ◽

Field Station ◽

Isoprene Emission ◽

Tundra Ecosystem ◽

Leaf Level ◽

Field Campaigns

Abstract. Whole-system fluxes of isoprene from a moist acidic tundra ecosystem and leaf-level emission rates of isoprene from a common species (Salix pulchra) in that same ecosystem were measured during three separate field campaigns. The field campaigns were conducted during the summers of 2005, 2010 and 2011 and took place at the Toolik Field Station (68.6° N, 149.6° W) on the north slope of the Brooks Range in Alaska, USA. The maximum rate of whole-system isoprene flux measured was over 1.2 mg C m−2 h−1 with an air temperature of 22 °C and a PAR level over 1500 μmol m−2 s−1. Leaf-level isoprene emission rates for S. pulchra averaged 12.4 nmol m−2 s−1 (27.4 μg C gdw−1 h−1) extrapolated to standard conditions (PAR = 1000 μmol m−2 s−1 and leaf temperature = 30 °C). Leaf-level isoprene emission rates were well characterized by the Guenther algorithm for temperature with published coefficients, but less so for light. Chamber measurements from a nearby moist acidic tundra ecosystem with little S. pulchra emitted significant amounts of isoprene, but at lower rates (0.45 mg C m−2 h−1) suggesting other significant isoprene emitters. Comparison of our results to predictions from a global model found broad agreement, but a detailed analysis revealed some significant discrepancies. An atmospheric chemistry box model predicts that the observed isoprene emissions have a significant impact on Arctic atmospheric chemistry, including a reduction of hydroxyl radical (OH) concentrations. Our results support the prediction that isoprene emissions from Arctic ecosystems will increase with global climate change.

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High vapour pressure deficit and low soil water availability enhance shoot growth responses of a C4 grass (Panicum coloratum cv. Bambatsi) to CO2 enrichment

Functional Plant Biology ◽

10.1071/pp97054 ◽

1998 ◽

Vol 25 (3) ◽

pp. 287 ◽

Cited By ~ 20

Author(s):

Saman P. Seneweera ◽

Oula Ghannoum ◽

Jann Conroy

Keyword(s):

Soil Water ◽

Elevated Co2 ◽

Vapour Pressure ◽

Shoot Growth ◽

Vapour Pressure Deficit ◽

C4 Grasses ◽

Growth Responses ◽

High Co2 ◽

C4 Grass ◽

Shoot Mass

The hypothesis that shoot growth responses of C4 grasses to elevated CO2 are dependent on shoot water relations was tested using a C4 grass, Panicum coloratum (NAD-ME subtype). Plants were grown for 35 days at CO2 concentrations of 350 or 1000 µL CO2 L-1. Shoot water relations were altered by growing plants in soil which was brought daily to 65, 80 or 100% field capacity (FC) and by maintaining the vapour pressure deficit (VPD) at 0.9 or 2.1 kPa. At 350 µL CO2 L-1, high VPD and lower soil water content depressed shoot dry mass, which declined in parallel at each VPD with decreasing soil water content. The growth depression at high VPD was associated with increased shoot transpiration, whereas at low soil water, leaf water potential was reduced. Elevated CO2 ameliorated the impact of both stresses by decreasing transpiration rates and raising leaf water potential. Consequently, high CO2 approximately doubled shoot mass and leaf length at a VPD of 2.1 kPa and soil water contents of 65 and 80% FC but had no effect on unstressed plants. Water use efficiency was enhanced by elevated CO2 under conditions of stress but this was primarily due to increases in shoot mass. High CO2 had a greater effect on leaf growth parameters than on stem mass. Elevated CO2 increased specific leaf area and leaf area ratio, the latter at high VPD only. We conclude that high CO2 increases shoot growth of C4 grasses by ameliorating the effects of stress induced by either high VPD or low soil moisture. Since these factors limit growth of field-grown C4 grasses, it is likely that their biomass will be enhanced by rising atmospheric CO2 concentrations.

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Photosynthetic responses to temperature, light flux-density, CO2 concentration and vapour pressure deficit in Eucalyptus tetrodonta grown under CO2 enrichment

Environmental Pollution ◽

10.1016/0269-7491(94)00088-u ◽

1995 ◽

Vol 90 (1) ◽

pp. 41-49 ◽

Cited By ~ 29

Author(s):

Derek Eamus ◽

G.A. Duff ◽

C.A. Berryman

Keyword(s):

Flux Density ◽

Vapour Pressure ◽

Light Flux ◽

Co2 Enrichment ◽

Vapour Pressure Deficit ◽

Co2 Concentration ◽

Photosynthetic Responses

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Responses of woody Cerrado species to rising atmospheric CO2 concentration and water stress: gains and losses

Functional Plant Biology ◽

10.1071/fp16138 ◽

2016 ◽

Vol 43 (12) ◽

pp. 1183 ◽

Cited By ~ 6

Author(s):

João Paulo Souza ◽

Nayara M. J. Melo ◽

Eduardo G. Pereira ◽

Alessandro D. Halfeld ◽

Ingrid N. Gomes ◽

...

Keyword(s):

Water Stress ◽

Elevated Co2 ◽

Global Climate ◽

Net Photosynthesis ◽

Co2 Concentration ◽

Atmospheric Co2 ◽

Ecosystem Functions ◽

Total Biomass ◽

High Co2 ◽

Atmospheric Co2 Concentration

The rise in atmospheric CO2 concentration ([CO2]) has been accompanied by changes in other environmental factors of global climate change, such as drought. Tracking the early growth of plants under changing conditions can determine their ecophysiological adjustments and the consequences for ecosystem functions. This study investigated long-term ecophysiological responses in three woody Cerrado species: Hymenaea stigonocarpa Mart. ex Hayne, Solanum lycocarpum A. St.-Hil. and Tabebuia aurea (Silva Manso) Benth. and Hook. f. ex S. Moore, grown under ambient and elevated [CO2]. Plants were grown for 515 days at ambient (430 mg dm–3) or elevated [CO2] (700 mg dm–3). Some plants were also subjected to water stress to investigate the synergy between atmospheric [CO2] and soil water availability, and its effect on plant growth. All three species showed an increase in maximum net photosynthesis (PN) and chlorophyll index under high [CO2]. Transpiration decreased in some species under high [CO2] despite daily watering and a corresponding increase in water use efficiency was observed. Plants grown under elevated [CO2] and watered daily had greater leaf area and total biomass production than plants under water stress and ambient [CO2]. The high chlorophyll and PN in cerrado plants grown under elevated [CO2] are an investment in light use and capture and higher Rubisco carboxylation rate, respectively. The elevated [CO2] had a positive influence on biomass accumulation in the cerrado species we studied, as predicted for plants under high [CO2]. So, even with water stress, Cerrado species under elevated [CO2] had better growth.

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Stomatal responses of Eucalyptus species to elevated CO2 concentration and drought stress

Scientia Agricola ◽

10.1590/s0103-90162003000200005 ◽

2003 ◽

Vol 60 (2) ◽

pp. 231-238 ◽

Cited By ~ 14

Author(s):

Walter de Paula Lima ◽

Paul Jarvis ◽

Sophia Rhizopoulou

Keyword(s):

Drought Stress ◽

Elevated Co2 ◽

Large Scale ◽

Stomatal Closure ◽

Co2 Concentration ◽

Eucalyptus Species ◽

Elevated Co2 Concentration ◽

Positive Effects ◽

Stomatal Responses ◽

Use Efficiency

Five species of Eucalyptus (E. grandis, E. urophylla, E. camaldulensis, E. torelliana, and E. phaeotrica), among the ten species most commonly used in large scale plantations, were selected for studies on the effects of elevated CO2 concentration [CO2] and drought stress on stomatal responses of 2.5-month old seedlings. The first three species belong to the subgenus Smphyomyrtus, whereas the fourth species belongs to the subgenus Corymbia and E. phaeotrica is from the subgenus Monocalyptus. Seedlings were grown in four pairs of open-top chambers, arranged to have 2 plants of each species in each chamber, with four replications in each of two CO2 concentrations: 350 ± 30 mumol mol-1 and 700 ± 30 mumol mol-1. After 100 days in the chambers, a series of gas exchange measurements were made. Half the plants in each chamber, one plant per species per chamber, were drought-stressed by withholding irrigation, while the remaining plants continued to be watered daily. Drought stress decreased stomatal conductance, photosynthesis and transpiration rates in all the species. The effect of drought stress on stomatal closure was similar in both [CO2]. The positive effects of elevated [CO2] on photosynthesis and water use efficiency were maintained longer during the stress period than under well-watered conditions. The photosynthetic rate of E. phaeotrica was higher even in the fourth day of the drought stress. Drought stress increased photoinhibition of photosynthesis, as measured by chlorophyll fluorescence, which varied among the species, as well as in relation to [CO2]. The results are in agreement with observed differences in stomatal responses between some eucalyptus species of the subgenera Symphyomyrtus and Monocalyptus.

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Partial rootzone drying and deficit irrigation increase stomatal sensitivity to vapour pressure deficit in anisohydric grapevines

Functional Plant Biology ◽

10.1071/fp09175 ◽

2010 ◽

Vol 37 (2) ◽

pp. 128 ◽

Cited By ~ 62

Author(s):

Marisa J. Collins ◽

Sigfredo Fuentes ◽

Edward W. R. Barlow

Keyword(s):

Water Use ◽

Vapour Pressure ◽

Sap Flow ◽

Deficit Irrigation ◽

Stomatal Closure ◽

Vapour Pressure Deficit ◽

Vitis Vinifera L ◽

Long Distance ◽

Stomatal Sensitivity ◽

Partial Rootzone Drying

The aim of this study was to investigate how alternative irrigation strategies affected grapevine (Vitis vinifera L.) stomatal response to atmospheric vapour pressure deficit (VPD). In two sites, application of partial rootzone drying (PRD) at 90–100% of crop evapotranspiration (ETc) increased stomatal sensitivity of Shiraz (Syrah) grapevines to high VPD compared with control vines irrigated with the same amount of water but applied on both sides of the vine. PRD significantly reduced vine water use (ESF) measured as sap flow and in dry conditions increased the depth of water uptake from the soil profile. In both experiments, PRD reduced vine water use by up to 50% at moderate VPD (~3 kPa) compared with control vines irrigated at the same level. In the same vines, the response to PRD applied at 100% ETc and deficit irrigation applied at 65% ETc was the same, increasing stomatal sensitivity to VPD and decreasing sap flow. Hydraulic signalling apparently did not play a role in changing stomatal sensitivity as there was no difference in stem water potentials between any of the treatment (PRD and DI) and control vines. This suggests that a long distance root-based chemical signal such as ABA may be responsible for the changes in stomatal behaviour. Shiraz grapevines have previously been classified as anisohydric-like, but application of PRD and DI increased stomatal closure in response to conditions of high evaporative demand making the vines behave in a more isohydric-like manner.

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