Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
Australian Journal of Botany Australian Journal of Botany Society
Southern hemisphere botanical ecosystems
RESEARCH ARTICLE

Relative importance of transpiration rate and leaf morphological traits for the regulation of leaf temperature

Madalena Vaz Monteiro A , Tijana Blanuša A B E , Anne Verhoef C , Paul Hadley A and Ross W. F. Cameron D
+ Author Affiliations
- Author Affiliations

A School of Agriculture, Policy and Development, University of Reading, RG6 6AR, UK.

B Royal Horticultural Society, Plant Sciences Department, Garden Wisley, Woking GU23 6QB, UK.

C Department of Geography and Environmental Science, School of Archaeology, Geography and Environmental Science, University of Reading, RG6 6AB, UK.

D Department of Landscape, University of Sheffield, S10 2TN, UK.

E Corresponding author. Email: tijanablanusa@rhs.org.uk

Australian Journal of Botany 64(1) 32-44 https://doi.org/10.1071/BT15198
Submitted: 29 August 2015  Accepted: 16 November 2015   Published: 12 February 2016

Abstract

Urban greening solutions such as green roofs help improve residents’ thermal comfort and building insulation. However, not all plants provide the same level of cooling. This is partially due to differences in plant structure and function, including different mechanisms that plants employ to regulate leaf temperature. Ranking of multiple leaf and plant traits involved in the regulation of leaf temperature (and, consequently, plants’ cooling ‘service’) is not well understood. We, therefore, investigated the relative importance of water loss, leaf colour, thickness and extent of pubescence for the regulation of leaf temperature, in the context of species for semi-extensive green roofs. Leaf temperature was measured with an infrared imaging camera in a range of contrasting genotypes within three plant genera (Heuchera, Salvia and Sempervivum). In three glasshouse experiments (each evaluating three or four genotypes of each genus), we varied water availability to the plants and assessed how leaf temperature altered depending on water loss and specific leaf traits. Greatest reductions in leaf temperature were closely associated with higher water loss. Additionally, in non-succulents (Heuchera, Salvia), lighter leaf colour and longer hair length (on pubescent leaves) both contributed to reduced leaf temperature. However, in succulent Sempervivum, colour and pubescence made no significant contribution; leaf thickness and rate of water loss were the key regulating factors. We propose that this can lead to different plant types having significantly different potentials for cooling. We suggest that maintaining transpirational water loss by sustainable irrigation and selecting urban plants with favourable morphological traits are the key to maximising thermal benefits provided by applications such as green roofs.

Additional keywords: leaf colour, leaf hairs, leaf temperature, leaf thickness, water deficit, water loss.


References

Akbari H, Pomerantz M, Taha H (2001) Cool surfaces and shade trees to reduce energy use and improve air quality in urban areas. Solar Energy 70, 295–310.
Cool surfaces and shade trees to reduce energy use and improve air quality in urban areas.Crossref | GoogleScholarGoogle Scholar |

Ansari AQ, Loomis WE (1959) Leaf temperatures. American Journal of Botany 46, 713–717.
Leaf temperatures.Crossref | GoogleScholarGoogle Scholar |

Billings WD, Morris RJ (1951) Reflection of visible and infrared radiation from leaves of different ecological groups. American Journal of Botany 38, 327–331.
Reflection of visible and infrared radiation from leaves of different ecological groups.Crossref | GoogleScholarGoogle Scholar |

Blanusa T, Vaz Monteiro MM, Fantozzi F, Vysini E, Li Y, Cameron RWF (2013) Alternatives to Sedum on green roofs: can broad leaf perennial plants offer better ‘cooling service’? Building and Environment 59, 99–106.
Alternatives to Sedum on green roofs: can broad leaf perennial plants offer better ‘cooling service’?Crossref | GoogleScholarGoogle Scholar |

Bowler DE, Buyung-Ali L, Knight TM, Pullin AS (2010) Urban greening to cool towns and cities: a systematic review of the empirical evidence. Landscape and Urban Planning 97, 147–155.
Urban greening to cool towns and cities: a systematic review of the empirical evidence.Crossref | GoogleScholarGoogle Scholar |

Budescu DV (1993) Dominance analysis: a new approach to the problem of relative importance of predictors in multiple regression. Psychological Bulletin 114, 542–551.
Dominance analysis: a new approach to the problem of relative importance of predictors in multiple regression.Crossref | GoogleScholarGoogle Scholar |

Cameron RWF, Harrison-Murray RS, Atkinson CJ, Judd HL (2006) Regulated deficit irrigation: a means to control growth in woody ornamentals. Journal of Horticultural Science & Biotechnology 81, 435–443.

Cameron RWF, Harrison-Murray RS, Fordham M, Wilkinson S, Davies WJ, Atkinson CJ, Else MA (2008) Regulated deficit irrigation of woody ornamentals to improve plant quality and precondition against drought stress. Annals of Applied Biology 153, 49–61.
Regulated deficit irrigation of woody ornamentals to improve plant quality and precondition against drought stress.Crossref | GoogleScholarGoogle Scholar |

Campbell DR, Wu CA, Travers SE (2010) Photosynthetic and growth responses of reciprocal hybrids to variation in water and nitrogen availability. American Journal of Botany 97, 925–933.
Photosynthetic and growth responses of reciprocal hybrids to variation in water and nitrogen availability.Crossref | GoogleScholarGoogle Scholar | 21622463PubMed |

Chaves MM, Pereira JS, Maroco J, Rodrigues ML, Ricardo CPP, Osorio ML, Carvalho I, Faria T, Pinheiro C (2002) How plants cope with water stress in the field? Photosynthesis and growth. Annals of Botany 89, 907–916.
How plants cope with water stress in the field? Photosynthesis and growth.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XlsVeitb4%3D&md5=8032e81adb2c58ce975ba107fcbb257dCAS | 12102516PubMed |

Ehleringer J (1982) The influence of water stress and temperature on leaf pubescence development in Encelia farinosa. American Journal of Botany 69, 670–675.
The influence of water stress and temperature on leaf pubescence development in Encelia farinosa.Crossref | GoogleScholarGoogle Scholar |

Ehleringer JR, Mooney HA (1978) Leaf hairs: Effects on physiological activity and adaptive value to a desert shrub. Oecologia 37, 183–200.
Leaf hairs: Effects on physiological activity and adaptive value to a desert shrub.Crossref | GoogleScholarGoogle Scholar |

Ferguson H, Eslick RF, Aase JK (1973) Canopy temperatures of barley as influenced by morphological characteristics. Agronomy Journal 65, 425–428.
Canopy temperatures of barley as influenced by morphological characteristics.Crossref | GoogleScholarGoogle Scholar |

França MGC, Prados LMZ, de Lemos-Filho JP, Ranieri BD, Vale FHA (2012) Morphophysiological differences in leaves of Lavoisiera campos-portoana (Melastomataceae) enhance higher drought tolerance in water shortage events. Journal of Plant Research 125, 85–92.
Morphophysiological differences in leaves of Lavoisiera campos-portoana (Melastomataceae) enhance higher drought tolerance in water shortage events.Crossref | GoogleScholarGoogle Scholar |

Garnier E, Shipley B, Roumet C, Laurent G (2001) A standardized protocol for the determination of specific leaf area and leaf dry matter content. Functional Ecology 15, 688–695.
A standardized protocol for the determination of specific leaf area and leaf dry matter content.Crossref | GoogleScholarGoogle Scholar |

Gates DM, Alderfer R, Taylor E (1968) Leaf temperatures of desert plants. Science 159, 994–995.
Leaf temperatures of desert plants.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DyaF1c7isVSisA%3D%3D&md5=b0b34f54041599c8757281fd97aeb69dCAS | 5636000PubMed |

Gausman HW, Cardenas R (1969) Effect of leaf pubescence of Gynura aurantiaca on light reflectance. Botanical Gazette 130, 158–162.
Effect of leaf pubescence of Gynura aurantiaca on light reflectance.Crossref | GoogleScholarGoogle Scholar |

Getter KL, Rowe DB (2006) The role of extensive green roofs in sustainable development. HortScience 41, 1276–1285.

Gill SE, Handley JF, Ennos AR, Pauleit S (2007) Adapting cities for climate change: the role of the green infrastructure. Built Environment 33, 115–133.

Grant OM, Tronina L, Jones HG, Chaves MM (2007) Exploring thermal imaging variables for the detection of stress responses in grapevine under different irrigation regimes. Journal of Experimental Botany 58, 815–825.
Exploring thermal imaging variables for the detection of stress responses in grapevine under different irrigation regimes.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXislCrt7w%3D&md5=9918f96afad208c5191558e808556979CAS | 17032729PubMed |

Grant OM, Davies MJ, James CM, Johnson AW, Leinonen I, Simpson DW (2012) Thermal imaging and carbon isotope composition indicate variation amongst strawberry (Fragaria × ananassa) cultivars in stomatal conductance and water use efficiency. Environmental and Experimental Botany 76, 7–15.
Thermal imaging and carbon isotope composition indicate variation amongst strawberry (Fragaria × ananassa) cultivars in stomatal conductance and water use efficiency.Crossref | GoogleScholarGoogle Scholar |

Grimmond S (2007) Urbanization and global environmental change: local effects of urban warming. The Geographical Journal 173, 83–88.
Urbanization and global environmental change: local effects of urban warming.Crossref | GoogleScholarGoogle Scholar |

Hsiao TC (1973) Plant responses to water stress. Annual Review of Plant Physiology 24, 519–570.
Plant responses to water stress.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE3sXlt1emurY%3D&md5=5a9c0f08063359192704757432f08520CAS |

Jones HG (1998) Stomatal control of photosynthesis and transpiration. Journal of Experimental Botany 49, 387–398.
Stomatal control of photosynthesis and transpiration.Crossref | GoogleScholarGoogle Scholar |

Jones HG (1999) Use of thermography for quantitative studies of spatial and temporal variation of stomatal conductance over leaf surfaces. Plant, Cell & Environment 22, 1043–1055.
Use of thermography for quantitative studies of spatial and temporal variation of stomatal conductance over leaf surfaces.Crossref | GoogleScholarGoogle Scholar |

Kluge M, Ting IP (1978) ‘Crassulacean acid metabolism: analysis of an ecological adaptation.’ (Springer-Verlag: New York)

Lewis DA, Nobel PS (1977) Thermal energy exchange model and water loss of a barrel cactus, Ferocactus acanthodes. Plant Physiology 60, 609–616.
Thermal energy exchange model and water loss of a barrel cactus, Ferocactus acanthodes.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DC%2BC3cnht1ehtQ%3D%3D&md5=ed8979c4a0aaf6b2327465062b6cc4e4CAS | 16660148PubMed |

López A, Molina-Aiz FD, Valera DL, Peña A (2012) Determining the emissivity of the leaves of nine horticultural crops by means of infrared thermography. Scientia Horticulturae 137, 49–58.
Determining the emissivity of the leaves of nine horticultural crops by means of infrared thermography.Crossref | GoogleScholarGoogle Scholar |

Nagase A, Dunnett N (2010) Drought tolerance in different vegetation types for extensive green roofs: effects of watering and diversity. Landscape and Urban Planning 97, 318–327.
Drought tolerance in different vegetation types for extensive green roofs: effects of watering and diversity.Crossref | GoogleScholarGoogle Scholar |

Oberndorfer E, Lundholm J, Bass B, Coffman RR, Doshi H, Dunnett N, Gaffin S, Köhler M, Liu KKY, Rowe B (2007) Green roofs as urban ecosystems: ecological structures, functions, and services. Bioscience 57, 823–833.
Green roofs as urban ecosystems: ecological structures, functions, and services.Crossref | GoogleScholarGoogle Scholar |

Oke TR (1987) ‘Boundary layer climates.’ (Methuen & Co: London)

Peng LLH, Jim CY (2013) Green-roof effects on neighborhood microclimate and human thermal sensation. Energies 6, 598–618.
Green-roof effects on neighborhood microclimate and human thermal sensation.Crossref | GoogleScholarGoogle Scholar |

Rowe DB (2011) Green roofs as a means of pollution abatement. Environmental Pollution 159, 2100–2110.
Green roofs as a means of pollution abatement.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXnsVyksr8%3D&md5=b9c03685d62236642b2b793cea79917aCAS | 21074914PubMed |

Saiz S, Kennedy C, Bass B, Pressnail K (2006) Comparative life cycle assessment of standard and green roofs. Environmental Science & Technology 40, 4312–4316.
Comparative life cycle assessment of standard and green roofs.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XkvVGgt78%3D&md5=5b74d90c17a6e186f570f3c0afe4f843CAS |

Schuepp PH (1993) Tansley review no. 59. Leaf boundary layers. New Phytologist 125, 477–507.
Tansley review no. 59. Leaf boundary layers.Crossref | GoogleScholarGoogle Scholar |

Skelton RP, Midgley JJ, Nyaga JM, Johnson SD, Cramer MD (2012) Is leaf pubescence of Cape Proteaceae a xeromorphic or radiation-protective trait? Australian Journal of Botany 60, 104–113.
Is leaf pubescence of Cape Proteaceae a xeromorphic or radiation-protective trait?Crossref | GoogleScholarGoogle Scholar |

Taha H (1997) Urban climates and heat islands: albedo, evapotranspiration, and anthropogenic heat. Energy and Buildings 25, 99–103.
Urban climates and heat islands: albedo, evapotranspiration, and anthropogenic heat.Crossref | GoogleScholarGoogle Scholar |

Teeri JA, Turner M, Gurevitch J (1986) The response of leaf water potential and crassulacean acid metabolism to prolonged drought in Sedum rubrotinctum. Plant Physiology 81, 678–680.
The response of leaf water potential and crassulacean acid metabolism to prolonged drought in Sedum rubrotinctum.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL28XkslKhsr8%3D&md5=d1e529318740ed31503d57a2a1481009CAS |

Vile D, Garnier E, Shipley B, Laurent G, Navas M-L, Roumet C, Lavorel S, Díaz S, Hodgson JG, Lloret F, Midgley GF, Poorter H, Rutherford MC, Wilson PJ, Wright IJ (2005) Specific leaf area and dry matter content estimate thickness in laminar leaves. Annals of Botany 96, 1129–1136.
Specific leaf area and dry matter content estimate thickness in laminar leaves.Crossref | GoogleScholarGoogle Scholar | 16159941PubMed |

Voss DH (1992) Relating colorimeter measurement of plant color to the Royal Horticultural Society colour chart. HortScience 27, 1256–1260.

Wong NH, Chen Y, Ong CL, Sia A (2003) Investigation of thermal benefits of rooftop garden in the tropical environment. Building and Environment 38, 261–270.
Investigation of thermal benefits of rooftop garden in the tropical environment.Crossref | GoogleScholarGoogle Scholar |