Interactions between tussock grass (Poa spp.) and Eucalyptus pauciflora seedlings near treeline in South-Eastern Australia
Observations of tussock grasses (mainly Poa species) and tree seedlings (Eucalyptus pauciflora) growing near treeline suggested that the tussocks may physically protect and compete with the tree seedlings. An analysis of nearest neighbour data from sites burnt in 1972–3 showed the there is a minimum separation between seedlings and tussocks, indicating that competition is taking place. Correlation and principal components analyses show that seedlings growing close to tussocks tend to be taller, with fewer stems and leaves than those growing further away. This same trend from tall, few-stemmed individuals to shorter multistemmed individuals also occurs with an increase in altitude. It is concluded that the trend in habit is related to exposure to environmental extremes. The concept of the regeneration niche and its application to E. pauciflora seedlings is discussed.
Unable to display preview. Download preview PDF.
- Billings, W.D., Mooney, H.A.: The ecology of arctic and alpine plants. Biol. Rev. 43, 481–529 (1968)Google Scholar
- Costin, A.B.: A study of the ecosystems of the Monaro Region of New South Wales. Sydney: Government Printer 1954Google Scholar
- Grubb, P.J.: The maintenance of species richness in plant communities: the importance of the regeneration niche. Biol. Rev. 52, 107–145 (1977)Google Scholar
- Harwood, C.E.: Ecological studies of timberline phenomena, pp. 244 (Ph.D. thesis, Australian National Univ., Canberra) 1976Google Scholar
- Moore, R.M., Williams, J.D.: A study of a subalpine woodlandgrassland boundary. Australian J. Ecol. 1, 145–155 (1976)Google Scholar
- Neter, J., Wasserman, W.: Applied linear statistical models. Illinois: Richard D. Irwin Inc. 1974Google Scholar
- Pielou, E.C.: The use of plant-to-neighbour distances for the detection of competition. J. Ecol. 50, 357–367 (1962)Google Scholar
- Pielou, E.C.: An introduction to mathematical ecology. New York: John Wiley and Sons 1969Google Scholar
- Poole, R.W.: An introduction to quantitative ecology. New York: McGraw Hill Book Co. 1974Google Scholar
- Slatyer, R.O.: Water deficits in timberline trees in the Snowy Mountains of south-eastern Australia. Oecologia (Berl.) 24, 357–366 (1976)Google Scholar
- Tranquillini, W.: Water relations and alpine timberline. In Water and plant life (O.L. Lange, L. Kappen, E.-D. Schulze, eds.), pp. 473–491 Berlin-Heidelberg-New York: Springer 1976Google Scholar
- Wardle, P.: An explanation for alpine timberline. New Zealand J. Bot. 9, 371–402 (1971)Google Scholar