International Journal of Biometeorology

, Volume 38, Issue 4, pp 188–193 | Cite as

Microclimatic differences between and within canopy gaps in a temperate rainforest

  • C. R. de Freitas
  • N. J. Enright
Original Article

Abstract

The microclimate in the understorey and in two canopy gaps of different size (249 m2 and 12.6 m2) within a temperate rainforest in northern New Zealand were characterised using net all-wave radiation (Q*), vapour pressure deficit (VPD), vertical air temperature gradient (VTG), and maximum and minimum air temperatures. Hemispherical fisheye photographs were used to define the exposure to the sky at each microclimate recording site both within and between gaps, and in the understorey. Under condiions of clear skies during the summer, with the sun close to its maximum altitude, the large gap centre had a mean daytime (0700–1700 hours)Q* of 452 W/m2. This value was similar to that estimated for an open field nearby, but three times greater thanQ* at the centre of the small gap, and six times greater than in the understorey. The east and west sides of both gaps had higher values ofQ* than the north and south sides. BothQ* and mean daily maximum temperature were strongly correlated with the amount of sky exposure. VPD and VTG were higher in gaps than in the understorey, with maximum values for both variables occurring at the centre of the large gap.

Key words

Forest microclimate Canopy openness Canopy gap Net radiation Sky view factor 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Anderson MC (1964) Studies of the woodland light climate. I. The photographic computation of light conditions. J Ecol 52: 27–41Google Scholar
  2. Barden LS (1979) Tree replacement in small canopy gaps of aTsuga canadensis forest in the southern Appalachians, Tennessee. Oecologia (Berlin) 44: 141–142Google Scholar
  3. Bazzaz FA, Pickett STA (1980) Physiological ecology of tropical succession: a comparative review. Annu Rev Ecol Syst 11: 287–310Google Scholar
  4. Bernhofer C (1992) Estimating forest evapotranspiration at a nonideal site. Agric For Meteorol 60: 17–32Google Scholar
  5. Brokaw NVL (1982) The definition of treefall gap and its effect on measures of forest dynamics. Biotropica 14: 158–160Google Scholar
  6. Brown ND, Whitmore TC (1992) Do dipterocarp seedlings really partition tropical rain forest gaps? Phil Trans R Soc Lond B 335: 369–378Google Scholar
  7. Burton PJ, Mueller-Dombois D (1984) Response ofMetrosideros polymorpha seedlings to experimental canopy opening. Ecology 65: 779–791Google Scholar
  8. Chazdon RL, Fetcher N (1984) Photosynthetic light environments in a lowland tropical rainforest in Costa Rica. J Ecol 72: 553–564Google Scholar
  9. Chazdon RL, Field CB (1987) Photographic estimation of photosynthetically active radiation: evaluation of a computerized technique. Oecologia (Berlin) 73: 525–532Google Scholar
  10. Clothier BE, Kerr JP, Talbot JS, Scotter DS (1982) Measured and estimated evapotranspiration from well watered crops. NZ J Agric Res 25: 301–307Google Scholar
  11. Collins BS, Pickett STA (1987) Influence of canopy opening on the environment and herb layer in a northern hardwoods forest. Vegetatio 70: 3–10Google Scholar
  12. Connell JH (1978) Diversity in tropical rainforests and coral reefs. Science 199: 1302–1310Google Scholar
  13. Denslow JS (1980) Gap partitioning among tropical rainforest trees. Biotropica 12: (Suppl) 47–55Google Scholar
  14. Denslow JS (1987) Tropical rainforest gaps and tree species diversity. Annu Rev Ecol Syst 18: 431–451Google Scholar
  15. Denslow JS, Schulz JC, Vitousek PM, Strain BR (1990) Growth responses of tropical shrubs to treefall gap environments. Ecology 71: 165–169Google Scholar
  16. Enright NJ, Cameron E (1988) The soil seedbank of kauri (Agathis australis) forest remnant near Auckland, New Zealand. NZ J Bot 26: 223–236Google Scholar
  17. Enright NJ, Bartlett RM, de Freitas CR (1993) Patterns of species composition, recruitment, and growth within canopy gaps in two New Zealand kauri (Agathis australis) forests. NZ J Bot. 31:361–373Google Scholar
  18. Fetcher N, Oberbauer SF, Strain BR (1985) Vegetation effects on microclimate in lowland tropical forest in Costa Rica. Int J Biometeorol 29: 145–155Google Scholar
  19. Grubb PJ, Whitmore TC (1966) A comparison of montane and lowland rain forest in Ecuador. II. The climate and its effects on the distribution and physiognomy of the forests. J Ecol 54:303–333Google Scholar
  20. Ghuman BS, Lal R (1987) Effects of partial clearing on microclimate in a humid tropical forest. Agric For Meteorol 40: 17–29Google Scholar
  21. Hartshorn GS (1978) Tree falls and tropical forest dynamics. In: Tomlinson PB, Zimmerman MH (eds) Tropical trees as living systems. Cambridge University Press, New York, pp 617–638Google Scholar
  22. Hartshorn GS (1980) Neotropical forest dynamics. Biotropica 12: (Suppl) 23–30Google Scholar
  23. Hibbs DE (1982) Gap dynamics in a hemlock-hardwood forest. Can J For Res 12: 522–527Google Scholar
  24. Longman KA, Jenik J (1974) Tropical forest and its environment. Longman, LondonGoogle Scholar
  25. MacDonald D, Norton DA (1992) Light environments in temperate New Zealand podocarp rainforests. NZ J Ecol 16: 15–22Google Scholar
  26. McAneney KJ, Predergast PT, Judd MJ, Green AE (1992) Observations of equilibrium evaporation from a windbreak-sheltered kiwifruit orchard. Agric For Meteorol 57: 253–264Google Scholar
  27. Ogden J (1983) The scientific reserves of Auckland University. II. Quantitative vegetation studies. Tane 29: 163–180Google Scholar
  28. Ogden J (1985) An introduction to plant demography with special reference to New Zealand trees. NZ J Bot 23: 751–772Google Scholar
  29. Ogden J, Wardle GM, Ahmed M (1987) Population dynamics of the emergent coniferAgathis australis (DDon) Lindl. (kauri) in New Zealand. II. Seedling population size and gap-phase regeneration. NZ J Bot 25: 231–242Google Scholar
  30. Ogden J, Fordham RA, Pilkington S, Serra RG (1991) Forest gap formation and closure along altitudinal gradient in Tongariro National Park, New Zealand. J Veget Sci 2: 165–172Google Scholar
  31. Orians GH (1982) The influence of tree-falls in tropical forests on tree species richness. Trop Ecol 23: 255–279Google Scholar
  32. Pinker R (1980) The microclimate of a dry tropical forest. Agric Meteorol 22: 249–265Google Scholar
  33. Popma J, Bongers F, Martinez-Ramos M, Veneklaas E (1988) Pioneer species distribution in treefall gaps in Neotropical rain forest; a gap definition and its consequences. J Trop Ecol 4: 77–88Google Scholar
  34. Poulson TL, Platt WJ (1989) Gap light regimes influence canopy tree diversity. Ecology 70: 553–555Google Scholar
  35. Richards P, Williamson GB (1975) Treefalls and patterns of understorey species in a wet lowland tropical forest. Ecology 56: 1226–1229Google Scholar
  36. Ricklefs RE (1977) Environmental heterogeneity and plant species diversity: a hypothesis. Am Nat 111: 376–381Google Scholar
  37. Runkle JR (1981) Gap regeneration in some old-growth forests of the eastern United States. Ecology 62: 1041–1051Google Scholar
  38. Runkle JR (1982) Patterns of disturbance in some old-growth mesic forests of eastern North America. Ecology 63: 1533–1546Google Scholar
  39. Runkle JR (1989) Synchrony of regeneration, gaps and latitudinal differences in tree species diversity. Ecology 70: 546–547Google Scholar
  40. SAS Institute (1985) SAS procedures guide for personal computers, Version 6 Edition. SAS Institute, Cary, North CarolinaGoogle Scholar
  41. Schulz JP (1960) Ecological studies on rainforest in Northern Surinam. North Holland, AmsterdamGoogle Scholar
  42. Thomas GM, Ogden J (1983) The scientific reserves of Auckland University. I. General introduction to their history, vegetation, climate and soils. Tane 29: 143–162Google Scholar
  43. Whitmore TC (1982) On pattern and process in forests. In: Newman EI (ed) The plant community as a working mechanism. Blackwell, Oxford, pp 45–59Google Scholar
  44. Williamson GB (1975) Pattern and seral composition in an old-growth beech-maple forest. Ecology 56: 727–731Google Scholar

Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  • C. R. de Freitas
    • 1
  • N. J. Enright
    • 2
  1. 1.Division of ScienceUniversity of Auckland, Tamaki CampusAucklandNew Zealand
  2. 2.Department of GeographyUniversity of MelbourneParkvilleAustralia

Personalised recommendations