BACKGROUND AND AIMS: A trade-off between shade tolerance and growth in high light is thought to underlie the temporal dynamics of humid forests. On the other hand, it has been suggested that tree species sorting on temperature gradients involves a trade-off between growth rate and cold resistance. Little is known about how these two major trade-offs interact. METHODS: Seedlings of Australian tropical and cool-temperate rainforest trees were grown in glasshouse environments to compare growth versus shade-tolerance trade-offs in these two assemblages. Biomass distribution, photosynthetic capacity and vessel diameters were measured in order to examine the functional correlates of species differences in light requirements and growth rate. Species light requirements were assessed by field estimation of the light compensation point for stem growth. RESULTS: Light-demanding and shade-tolerant tropical species differed markedly in relative growth rates (RGR), but this trend was less evident among temperate species. This pattern was paralleled by biomass distribution data: specific leaf area (SLA) and leaf area ratio (LAR) of tropical species were significantly positively correlated with compensation points, but not those of cool-temperate species. The relatively slow growth and small SLA and LAR of Tasmanian light-demanders were associated with narrow vessels and low potential sapwood conductivity. CONCLUSIONS: The conservative xylem traits, small LAR and modest RGR of Tasmanian light-demanders are consistent with selection for resistance to freeze-thaw embolism, at the expense of growth rate. Whereas competition for light favours rapid growth in light-demanding trees native to environments with warm, frost-free growing seasons, frost resistance may be an equally important determinant of the fitness of light-demanders in cool-temperate rainforest, as seedlings establishing in large openings are exposed to sub-zero temperatures that can occur throughout most of the year.
BACKGROUND AND AIMS: A trade-off between shade tolerance and growth in high light is thought to underlie the temporal dynamics of humid forests. On the other hand, it has been suggested that tree species sorting on temperature gradients involves a trade-off between growth rate and cold resistance. Little is known about how these two major trade-offs interact. METHODS: Seedlings of Australian tropical and cool-temperate rainforest trees were grown in glasshouse environments to compare growth versus shade-tolerance trade-offs in these two assemblages. Biomass distribution, photosynthetic capacity and vessel diameters were measured in order to examine the functional correlates of species differences in light requirements and growth rate. Species light requirements were assessed by field estimation of the light compensation point for stem growth. RESULTS: Light-demanding and shade-tolerant tropical species differed markedly in relative growth rates (RGR), but this trend was less evident among temperate species. This pattern was paralleled by biomass distribution data: specific leaf area (SLA) and leaf area ratio (LAR) of tropical species were significantly positively correlated with compensation points, but not those of cool-temperate species. The relatively slow growth and small SLA and LAR of Tasmanian light-demanders were associated with narrow vessels and low potential sapwood conductivity. CONCLUSIONS: The conservative xylem traits, small LAR and modest RGR of Tasmanian light-demanders are consistent with selection for resistance to freeze-thaw embolism, at the expense of growth rate. Whereas competition for light favours rapid growth in light-demanding trees native to environments with warm, frost-free growing seasons, frost resistance may be an equally important determinant of the fitness of light-demanders in cool-temperate rainforest, as seedlings establishing in large openings are exposed to sub-zero temperatures that can occur throughout most of the year.
Authors: Daniel Falster; Rachael Gallagher; Elizabeth H Wenk; Ian J Wright; Dony Indiarto; Samuel C Andrew; Caitlan Baxter; James Lawson; Stuart Allen; Anne Fuchs; Anna Monro; Fonti Kar; Mark A Adams; Collin W Ahrens; Matthew Alfonzetti; Tara Angevin; Deborah M G Apgaua; Stefan Arndt; Owen K Atkin; Joe Atkinson; Tony Auld; Andrew Baker; Maria von Balthazar; Anthony Bean; Chris J Blackman; Keith Bloomfield; David M J S Bowman; Jason Bragg; Timothy J Brodribb; Genevieve Buckton; Geoff Burrows; Elizabeth Caldwell; James Camac; Raymond Carpenter; Jane A Catford; Gregory R Cawthray; Lucas A Cernusak; Gregory Chandler; Alex R Chapman; David Cheal; Alexander W Cheesman; Si-Chong Chen; Brendan Choat; Brook Clinton; Peta L Clode; Helen Coleman; William K Cornwell; Meredith Cosgrove; Michael Crisp; Erika Cross; Kristine Y Crous; Saul Cunningham; Timothy Curran; Ellen Curtis; Matthew I Daws; Jane L DeGabriel; Matthew D Denton; Ning Dong; Pengzhen Du; Honglang Duan; David H Duncan; Richard P Duncan; Marco Duretto; John M Dwyer; Cheryl Edwards; Manuel Esperon-Rodriguez; John R Evans; Susan E Everingham; Claire Farrell; Jennifer Firn; Carlos Roberto Fonseca; Ben J French; Doug Frood; Jennifer L Funk; Sonya R Geange; Oula Ghannoum; Sean M Gleason; Carl R Gosper; Emma Gray; Philip K Groom; Saskia Grootemaat; Caroline Gross; Greg Guerin; Lydia Guja; Amy K Hahs; Matthew Tom Harrison; Patrick E Hayes; Martin Henery; Dieter Hochuli; Jocelyn Howell; Guomin Huang; Lesley Hughes; John Huisman; Jugoslav Ilic; Ashika Jagdish; Daniel Jin; Gregory Jordan; Enrique Jurado; John Kanowski; Sabine Kasel; Jürgen Kellermann; Belinda Kenny; Michele Kohout; Robert M Kooyman; Martyna M Kotowska; Hao Ran Lai; Etienne Laliberté; Hans Lambers; Byron B Lamont; Robert Lanfear; Frank van Langevelde; Daniel C Laughlin; Bree-Anne Laugier-Kitchener; Susan Laurance; Caroline E R Lehmann; Andrea Leigh; Michelle R Leishman; Tanja Lenz; Brendan Lepschi; James D Lewis; Felix Lim; Udayangani Liu; Janice Lord; Christopher H Lusk; Cate Macinnis-Ng; Hannah McPherson; Susana Magallón; Anthony Manea; Andrea López-Martinez; Margaret Mayfield; James K McCarthy; Trevor Meers; Marlien van der Merwe; Daniel J Metcalfe; Per Milberg; Karel Mokany; Angela T Moles; Ben D Moore; Nicholas Moore; John W Morgan; William Morris; Annette Muir; Samantha Munroe; Áine Nicholson; Dean Nicolle; Adrienne B Nicotra; Ülo Niinemets; Tom North; Andrew O'Reilly-Nugent; Odhran S O'Sullivan; Brad Oberle; Yusuke Onoda; Mark K J Ooi; Colin P Osborne; Grazyna Paczkowska; Burak Pekin; Caio Guilherme Pereira; Catherine Pickering; Melinda Pickup; Laura J Pollock; Pieter Poot; Jeff R Powell; Sally A Power; Iain Colin Prentice; Lynda Prior; Suzanne M Prober; Jennifer Read; Victoria Reynolds; Anna E Richards; Ben Richardson; Michael L Roderick; Julieta A Rosell; Maurizio Rossetto; Barbara Rye; Paul D Rymer; Michael A Sams; Gordon Sanson; Hervé Sauquet; Susanne Schmidt; Jürg Schönenberger; Ernst-Detlef Schulze; Kerrie Sendall; Steve Sinclair; Benjamin Smith; Renee Smith; Fiona Soper; Ben Sparrow; Rachel J Standish; Timothy L Staples; Ruby Stephens; Christopher Szota; Guy Taseski; Elizabeth Tasker; Freya Thomas; David T Tissue; Mark G Tjoelker; David Yue Phin Tng; Félix de Tombeur; Kyle Tomlinson; Neil C Turner; Erik J Veneklaas; Susanna Venn; Peter Vesk; Carolyn Vlasveld; Maria S Vorontsova; Charles A Warren; Nigel Warwick; Lasantha K Weerasinghe; Jessie Wells; Mark Westoby; Matthew White; Nicholas S G Williams; Jarrah Wills; Peter G Wilson; Colin Yates; Amy E Zanne; Graham Zemunik; Kasia Ziemińska Journal: Sci Data Date: 2021-09-30 Impact factor: 6.444