Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-22T17:53:43.387Z Has data issue: false hasContentIssue false

Understorey light environments in a north-east Australian rain forest before and after a tropical cyclone

Published online by Cambridge University Press:  10 July 2009

S. M. Turton
Affiliation:
Department of Geography, James Cook University of North Queensland, Cairns Campus, PO Box 6811, Cairns, Q. 4870, Australia

Abstract

This paper describes estimates of canopy openness and associated light availability in the understorey of a north-east Australian rain forest before and immediately after a tropical cyclone. On the basis of 20 hemispherical (fisheye) canopy photographs it was shown that direct, diffuse and total site factors increased significantly as a result of the slight-to-moderate canopy disturbance caused by the cyclone. In the understorey, median total site factors ranged from 2.5–3.4% before the cyclone and from 6.0–8.6% after the cyclone, representing a 2- to 3-fold increase in potential light availability. Following the cyclone, mean relative gap frequencies increased substantially at all altitudes but particularly at canopy positions more than 70° above the horizon. Cyclone-induced canopy disturbance not only reduced the complexity of the understorey light regime but may have also increased the seasonal variability of light within the understorey of the forest during the interval of canopy recovery. The implications of these results for the ecophysiology of understorey tree seedlings and saplings at several temporal scales are discussed.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

LITERATURE CITED

Anderson, M. C. 1964. Studies of the woodland light climate I: the photographic computation of light conditions. Journal of Ecology 52:2751.CrossRefGoogle Scholar
Anderson, M. C. 1971. Radiation and crop structure. Pp. 412467 in Sestak, Z., Catsky, T. & Jarvis, P. G. (eds). Plant photosynthetic production: manual of methods. Dr W. Junk, The Hague, 819 pp.Google Scholar
Anderson, M. C. 1981. The geometry of leaf distribution in some south-eastern Australian forests. Agricultural Meteorology 25:195205.CrossRefGoogle Scholar
Bazzaz, E. A. 1991. Regeneration of tropical forests: physiological responses of pioneer and secondary species. Pp. 91118 in Gomez-Pompa, A., Whitmore, T. C. & Hadley, M. (eds). Rain forest regeneration and management. UNESCO, Paris. 457 pp.Google Scholar
Bonell, M., Gilmour, D. A. & Cassells, D. S. 1986. The storm runoff response to various rainfall systems on the wet tropical coast of northeast Queensland. East-West Centre, Environmental and Policy Institute, Working Paper, Honolulu, Hawaii.Google Scholar
Brokaw, N. V. L. 1985. Treefalls, regrowth, and community structure in tropical forests. Pp. 5369 in Pickett, S. T. A. & White, P. S. (eds). The ecology of natural disturbance and patch dynamics. Academic Press, Orlando & London. 472 pp.Google Scholar
Chazdon, R. L. 1988. Sunflecks and their importance to forest understorey plants. Advances in Ecological Research 18:163.CrossRefGoogle Scholar
Crow, T. R. 1980. A rain forest chronicle: a 30 year record of change in structure and composition at El Verde, Puerto Rico. Biotropica 1:4255.CrossRefGoogle Scholar
Denslow, J. S. 1987. Tropical rain forest gaps and tree species diversity. Annual Review of Ecology and Systematics, 18:431451.CrossRefGoogle Scholar
Evans, G. C. & Coombe, D. E. 1959. Hemispherical and woodland canopy photography and the light climate. Journal of Ecology 47:103113.CrossRefGoogle Scholar
Gentilli, J. 1972. Australian climate patterns. Nelson, Melbourne. 125 p.Google Scholar
Hartshorn, G. S. 1980. Neotropical forest dynamics. Biotropica 12:2330.CrossRefGoogle Scholar
Hopkins, M. S., Tracey, J. G. & Graham, A. W. 1990. The size and composition of soil seed-banks in remnant patches of three structural rainforest types in north Queensland. Australian Journal of Ecology 15:4350.CrossRefGoogle Scholar
Laffan, M. D. 1988. Soils and land use on the Atherton Tableland, north Queensland. CSIRO Soils and Land Use Series, No. 61., Canberra. 72 p.Google Scholar
Lee, D. W. 1987. The spectral distribution of radiation in two neotropical rainforests. Biotropica 19:161166.CrossRefGoogle Scholar
Moon, P. & Spencer, D. E. 1942. Illumination from a nonuniform sky. Illumination Engineering 37:707726.Google Scholar
Pearcy, R. W. 1989. Radiation and light measurements. Pp. 97116 in Pearcy, R. W., Ehleringer, J. R., Mooney, H. A. & Rundel, P. W. (eds). Plant physiological ecology: field methods and instrumentation. Chapman & Hall, London & New York. 457 pp.CrossRefGoogle Scholar
Swaine, M. D., Lieberman, D. & Putz, F. E. 1987. The dynamics of tree populations in tropical forest: a review. Journal of Tropical Ecology 3:359366.CrossRefGoogle Scholar
Tracey, J. G. 1982. The vegetation of the humid tropical region of North Queensland, CSIRO Publication, Melbourne. 124 pp.Google Scholar
Unwin, G. L., Applegate, G. B., Stocker, G. C. & Nicholson, D. I. 1988. Initial effects of tropical cyclone ‘Winifred’ on forests of north Queensland. Proceedings of the Ecological Society of Australia 15:283296.Google Scholar
Webb, L. J. 1958. Cyclones as an ecological factor in tropical lowland rainforest, North Queensland. Australian Journal of Botany 6:220228.CrossRefGoogle Scholar
Whitmore, T. C. 1974. Change with time and the role of cyclones in tropical rainforest on Kolomhangara, Solomon Islands. Commonwealth Forestry Institute Paper 46.Google Scholar
Whitmore, T. C. 1978. Gaps in the forest canopy. Pp. 639655 in Tomlinson, P. B. & Zimmerman, M. H. (eds). Tropical trees as living systems. Cambridge University Press. 675 pp.Google Scholar
Whitmore, T. C. 1991. Tropical rain forest dynamics and its implications for management. Pp. 6789 in Gomez-Pompa, A., Whitmore, T. C. & Hadley, M. (eds). Rain forest regeneration and management. UNESCO, Paris. 457 pp.Google Scholar