Canopy occupancy: How much of the space in plant communities is filled?
- 47 Downloads
A major gap in our knowledge of plant communities is how much of their volume is occupied by plant material (stem, leaf or reproductive structure). This is basic knowledge and may be crucial for the concept of competition for space. We sampled two grassland communities and two shrublands in both Italy and New Zealand. The height of the canopy was measured by a point quadrat method, and the volume of plant material, after cutting, by displacement of water. From 0.5% to 2.9% of the canopy was occupied by plant material. Occupancy was lower in the Italian communities, which we tentatively attribute to the climate. It did not differ significantly between grasslands and shrublands. Our data suggest that physical space is probably never limiting by itself in terrestrial higher-plant communities, so that competition for space, distinct from competition for resources such as light, water and nutrients, is not likely to exist.
KeywordsCommunity volume Competition for space Plant volume Space filling
Unable to display preview. Download preview PDF.
- Acosta A., Blasi C., Di Marzio P. &Mazzoleni S. (1996): Architectural patterns of “macchia” shrubs in Mediterranean Italy.Coenoses 11: 69–72.Google Scholar
- Clements F.E., Weaver J.E. &Hanson H.C. (1929):Plant competition: an analysis of community functions. Carnegie Institute, Washington.Google Scholar
- de Rereffye P. &Houllier F. (1997): Modelling plant growth and architecture: Some recent advances and applications to agronomy and forestry.Curr. Sci. 73: 984–992.Google Scholar
- Faliński J.B. (1973): Herb layer filling by plant cormus in theQuerco-Carpinetum community in the Bialowieża National Park.Phytocoenosis 2: 123–142.Google Scholar
- Greig-Smith P. (1983):Quantitative plant ecology. Ed. 3. Blackwell, Oxford.Google Scholar
- Kubíková J. &Rejmánek M. (1973): Notes on some quantitative methods in the study of plant community structure.Preslia 45: 154–164.Google Scholar
- Lamont B.B., Hopkins A.J.M. &Hnatiuk R.J. (1984): The flora — composition, diversity and origins. In:Pate J.S. &Beard J.S. (eds.),Kwongan, plant life of the sandplain, University of Western Australia Press, Nedlands, pp. 27–50.Google Scholar
- Newman E.I. (1983): Interactions between plants. In:Lange O.L., Nobel P.S., Osmond C.B. &Ziegler H. (eds.),Encyclopedia of plant physiology, New Series, Volume 12C: Physiological plant ecology III., Springer-Verlag, Berlin, pp. 679–710.Google Scholar
- Niklas K.J. (1992):Plant biomechanics: an engineering approach to plant form and function. University of Chicago Press, Chicago.Google Scholar
- Vasseur L., Irwin D.L. &Aarssen L.W. (1995): Size versus number of offspring as predictors of success under competition inLemna minor (Lemnaceae).Ann. Bot. Fenn. 32: 169–178.Google Scholar