Australian Journal of Botany Australian Journal of Botany Society
Southern hemisphere botanical ecosystems

Water relations of woody plants on contrasting soils during drought: does edaphic compensation account for dry rainforest distribution?

Timothy J. Curran A B , Peter J. Clarke A and Nigel W. M. Warwick A

A Botany, School of Environmental and Rural Science, University of New England, Armidale NSW 2351, Australia.

B Corresponding author. Current address: The School for Field Studies, PO Box 141, Yungaburra, Qld 4884, Australia. Email:

Australian Journal of Botany 57(8) 629-639
Submitted: 31 July 2009  Accepted: 16 November 2009   Published: 8 February 2010


The occurrence of dry rainforest in climates considered drier than the recognised limit for rainforest has been explained by the edaphic compensation hypothesis, which proposed that finer-textured soils facilitate the occurrence of rainforest at climatic extremes. We tested this by examining the effect of soil type on the water relations and plant traits of four dry rainforest species, during a severe drought and subsequent non-drought periods. We predicted plants growing in sandy soils would exhibit higher levels of water stress (lower predawn water potential and stomatal conductance) and possess morphological and physiological traits that more typically reflect drought resistance (late leaf fall in deciduous species, low specific leaf area, vertical leaf angles and stomata that close at low water potential) than those growing in loam soils. During drought, levels of water stress were similar across soil types, while post-drought plants on sandy soils were less stressed. Soil type did not cause shifts in drought tolerance traits, suggesting there has been no ecotypic differentiation of dry rainforest species across soil types for these traits. Hence, we found no support for the edaphic compensation hypothesis in adult plants; future studies should consider other life-cycle stages, such as seedlings.


We dedicate this paper to our friend, Flute Cannon, who passed away in 2008. Flute and her husband, Kerry, both of ‘Bondi’ Warialda are thanked for their interest and hospitality and for access to their property. We extend our thanks to Nicholas Curran, Benedict Hennessy, Richard Willis, John Gorham, Ian Simpson and Kristy Munro for their assistance with field work, sometimes under very extreme and trying conditions. The late John Williams provided us with useful and interesting discussions concerning dry rainforest species and Stuart Cairns and Mike Ramsey lent statistical advice. Laurie O’Donnell conducted the soil particle-size analyses. The hospitality of Bill Croker and his family at the UNE Douglas McMaster Field Station was also appreciated. The Northern Slopes Rural Lands Protection Board and the NSW National Parks and Wildlife Service Northern Plains region are thanked for access to land under their control. This project was funded by an Australian Postgraduate Award, an NCW Beadle Scholarship, an NCW Beadle Grant-in-Aid, and an ESA Student Research Travel Award to TJC. This research was carried out under licence to TJC (Threatened Species Certificate no. WD025). Craig Willis and Jo Lello are thanked for comments on earlier drafts of the manuscript.


Ackerly D (2004) Functional strategies of chaparral shrubs in relation to seasonal water deficit and disturbance. Ecological Monographs 74, 25–44.
CrossRef | open url image1

Acocks JPH (1953) Veld types of South Africa. Memoirs of the Botanical Survey of South Africa 28, 1–128. open url image1

Addington RN, Donovan LA, Mitchell RJ, Vose JM, Pecot SD, Jack SB, Hacke UG, Sperry JS, Oren R (2006) Adjustments in hydraulic architecture of Pinus palustris maintain similar stomatal conductance in xeric and mesic habitats. Plant, Cell & Environment 29, 535–545.
CrossRef | CAS | PubMed | open url image1

Alizai HU, Hulbert LC (1970) Effects of soil texture on evaporative loss and available water in semi-arid climates. Soil Science 110, 328–332.
CrossRef | open url image1

Ash J (1988) The location and stability of rainforest boundaries in north-eastern Queensland, Australia. Journal of Biogeography 15, 619–630.
CrossRef | open url image1

Attiwill PM, Clayton-Greene KA (1984) Studies of gas exchange and development in a subhumid woodland. Journal of Ecology 72, 285–294.
CrossRef | CAS | open url image1

Bannister P (1976) ‘Introduction to Physiological Plant Ecology.’ (Blackwell Scientific Publications: Oxford, UK)

Baur GN (1957) Nature and distribution of rainforests in NSW. Australian Journal of Botany 5, 190–233.
CrossRef | open url image1

Benson JS, Dick R, Zubovic A (1996) Semi-evergreen vine thicket vegetation at Derra Derra Ridge, Bingara, New South Wales. Cunninghamia 4, 497–510. open url image1

Borchert R (1994) Soil and stem water storage determine phenology and distribution of tropical dry forest trees. Ecology 75, 1437–1449.
CrossRef | open url image1

Bowman DMJS (2000) ‘Australian Rainforests: Islands of Green in a Land of Fire.’ (Cambridge University Press: Cambridge)

Bureau of Meteorology (2003) Drought statement – Issued 4th February 2003 (Statement on Drought for the 10 and 14 month periods ending 31st January 2003). URL

Bureau of Meteorology (2004) ‘Climatic data for Bingara Post Office, Moree Airport and Warialda Post Office.’ (Bureau of Meteorology: Moree BOM Station)

Bureau of Meteorology (2005) Australian climate zones – major classification groups (based on the Köppen classification). URL

Cornelissen JHC, Lavorel S, Garnier E, Díaz S, Buchmann N, Gurvich DE, Reich PB, ter Steege H, Morgan HD, van der Heijden MGA, Pausas JG, Poorter H (2003) A handbook of protocols for standardised and easy measurement of plant functional traits worldwide. Australian Journal of Botany 51, 335–380.
CrossRef | open url image1

Cowan IR (1981) Coping with water stress. In ‘The Biology of Australian Plants’ (Eds JS Pate, AJ McComb) pp. 1–32. (University of Western Australia Press: Nedlands, Western Australia)

Cowling RM (1983) Phytochorology and vegetation history in the south-east cape, South Africa. Journal of Biogeography 10, 393–419.
CrossRef | open url image1

Curran TJ (2006) ‘Rainforest, drought and soil type: phytogeography and functional and evolutionary ecology of dry rainforests on the western slopes of NSW.’ PhD thesis, University of New England, Armidale.

Curran TJ, Clarke PJ, Bruhl JB (2008) A broad typology of dry rainforests on the western slopes of New South Wales. Cunninghamia 10, 381–405. open url image1

Day PR (1965) Particle fractionation and particle-size analysis. In ‘Methods of Soil Analysis. Part 1: Physical and Mineralogical Properties, Including Statistics of Measurement and Sampling’ (Eds CA Black, DD Evans, JL White, LE Ensminger, FE Clark) pp. 545–567. (American Society of Agronomy, Inc.: Madison, WI, USA)

Eamus D (1999) Ecophysiological traits of deciduous and evergreen woody species in the seasonally dry tropics. Trends in Ecology & Evolution 14, 11–16.
CrossRef | open url image1

Ehleringer JR , Osmond CB (1989) Stable isotopes. In ‘Plant physiological ecology: Field methods and instrumentation’ (Eds RW Pearcy, JR Ehleringer, HA Mooney, PW Rundel) pp. 281–300. (Chapman & Hall: London)

Filella I, Penuelas J (2003) Partitioning of water and nitrogen in co-occurring Mediterranean woody shrub species of different evolutionary history. Oecologia 137, 51–61.
CrossRef | PubMed | open url image1

Gillison AN (1987) The ‘dry’ rainforests of Terra Australis. In ‘The rainforest legacy. Australian national rainforests study’ (Eds G Werren, AP Kershaw), pp. 305–21. (Australian Government Publishing Service: Canberra)

Groom PK, Lamont BB (1997) Xerophytic implications of increased sclerophylly: interactions with water and light in Hakea psilorrhyncha seedlings. The New Phytologist 136, 231–237.
CrossRef | open url image1

Hacke UG, Sperry JS, Ewers BE, Ellsworth DS, Schafer KVR, Oren R (2000) Influence of soil porosity on water use in Pinus taeda. Oecologia 124, 495–505.
CrossRef | open url image1

Hillel D, Tadmore N (1962) Water regime and vegetation in the Central Negev Highlands of Israel. Ecology 43, 33–41.
CrossRef | open url image1

Hultine KR, Koepke DF, Pockman WT, Fravolini A, Sperry JS, Williams DG (2006) Influence of soil texture on hydraulic properties and water relations of a dominant warm-desert phreatophyte. Tree Physiology 26, 313–323.
CrossRef | CAS | PubMed | open url image1

Karoly D , Risbey J , Reynolds A (2003) ‘Global warming contributes to Australia’s worst drought.’ (World Wildlife Fund Australia: Sydney)

Keith DA (2004) ‘Ocean shores to desert dunes: the native vegetation of NSW and ACT.’ (New South Wales Government: Sydney)

King DA (1997) The functional significance of leaf angle in Eucalyptus. Australian Journal of Botany 45, 619–639.
CrossRef | open url image1

Kramer PJ , Boyer JS (1995) ‘Water relations of plants and soils.’ (Academic Press: San Diego)

Lamont BB, Groom PK, Cowling RM (2002) High leaf mass per area of related species assemblages may reflect low rainfall and carbon isotope discrimination rather than low phosphorus and nitrogen concentrations. Functional Ecology 16, 403–412.
CrossRef | open url image1

Lewis JP (1991) Three levels of floristic variation in the forests of Chaco, Argentina. Journal of Vegetation Science 2, 125–130.
CrossRef | open url image1

McDonald RC , Isbell RF (1984) Soil Profile. In ‘Australian Soil and Land Survey Field Handbook’ In (Eds RC McDonald, RF Isbell, JG Speight, J Walker, MS Hopkins) pp. 83–126. (Inkata Press: Melbourne)

McDonald WJF (1996) ‘Spatial and temporal patterns in the dry seasonal subtropical rainforests of eastern Australia, with particular reference to the vine thickets of central and southern Queensland.’ PhD Thesis, University of New England, Armidale.

Medina E, Francisco M (1994) Photosynthesis and water relations of savanna tree species differing in leaf phenology. Tree Physiology 14, 1367–1382.
PubMed |
open url image1

Monson RK, Smith SD, Gehring JL, Bowman WD, Szarek SR (1992) Physiological differentiation within an Encelia farinosa population along a short topographic gradient in the Sonoran Desert. Functional Ecology 6, 751–759.
CrossRef | open url image1

Myers BA, Duff GA, Eamus D, Fordyce IR, O’Grady A, Williams RJ (1997) Seasonal variation in water relations of trees of differing leaf phenology in a wet–dry tropical savanna near Darwin, northern Australia. Australian Journal of Botany 45, 225–240.
CrossRef | open url image1

Myers BA, Neales TF (1984) Seasonal changes in the water relations of Eucalyptus behriana F.Muell. and E. microcarpa (Maiden) Maiden in the field. Australian Journal of Botany 13, 29–84. open url image1

Nano CE, Clarke PJ (2008) Variegated desert vegetation: covariation of edaphic and fire variables provides a framework for understanding mulga-spinifex coexistence. Austral Ecology 33, 848–862.
CrossRef | open url image1

Noy-Meir I (1973) Desert ecosystems: environment and producers. Annual Review of Ecology and Systematics 4, 25–51.
CrossRef | open url image1

Palmer AR (1991) Vegetation/environment relationships in the central area of the eastern Cape midlands, South Africa. Coenoses 6, 29–38. open url image1

Reich PB, Ellsworth DS, Walters MB, Vose JM, Gresham C, Volin JC, Bowman WD (1999) Generality of leaf trait relationships: a test across six biomes. Ecology 80, 1955–1969. open url image1

Rice KJ, Matzner SL, Byer W, Brown JR (2004) Patterns of tree dieback in Queensland, Australia: the importance of drought stress and the role of resistance to cavitation. Oecologia 139, 190–198.
CrossRef | PubMed | open url image1

Salleo S, Nardini A, Lo Gullo MA (1997) Is sclerophylly of Mediterranean evergreens an adaptation to drought? The New Phytologist 135, 603–612.
CrossRef | open url image1

Smith SD , Monson RK , Anderson JE (1997) ‘Physiological ecology of North American desert plants.’ (Springer-Verlag: Berlin)

Sokal RR , Rohlf FJ (1995) ‘Biometry: the principles and practice of statistics in biological research.’ 3rd edn. (W.H. Freeman and Company: New York)

Sperry JS, Hacke UG (2002) Desert shrub water relations with respect to soil characteristics and plant functional type. Functional Ecology 16, 367–378.
CrossRef | open url image1

Tighe M, Lockwood P, Wilson S, Lisle L (2004) Comparison of digestion methods for ICP-OES analysis of wide range of analytes in heavy metal contaminated soil samples with specific reference to arsenic and antimony. Communications in Soil Science and Plant Analysis 35, 1369–1385.
CrossRef | CAS | open url image1

Tunstall BR, Connor DJ (1975) Internal water balance of brigalow (Acacia harpophylla F. Muell.) under natural conditions. Australian Journal of Plant Physiology 2, 489–499.
CrossRef | open url image1

Webb LJ , Tracey JG (1981) Australian rainforests: patterns and change. In ‘Ecological Biogeography of Australia’ (Ed. A Keast) pp. 605–94. (W. Junk: The Hague)

Westoby M (1998) A leaf-height-seed (LHS) plant ecology strategy scheme. Plant and Soil 199, 213–227.
CrossRef | CAS | open url image1

Westoby M (2002) Choosing species to study. Trends in Ecology & Evolution 17, 587.
CrossRef | open url image1

Williams RJ, Myers BA, Muller WJ, Duff GA, Eamus D (1997) Leaf phenology of woody species in a North Australian tropical savanna. Ecology 78, 2542–2558. open url image1

Wright IJ, Groom PK, Lamont BB, Poot P, Prior LD, Reich PB, Schulze ED, Veneklaas EJ, Westoby M (2004) Leaf trait relationships in Australian plant species. Functional Plant Biology 31, 551–558.
CrossRef | open url image1

Wu XB, Archer S (2005) Scale-dependent influence of topography-based hydrological features on patterns of woody plant encroachment in savanna landscapes. Landscape Ecology 20, 733–742.
CrossRef | open url image1

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