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Chapter 8 - Plant Demography and Dynamics: Fire Traps

from Part II - The Savanna Garden: Grassy Vegetation and Plant Dynamics

Published online by Cambridge University Press:  09 September 2021

Norman Owen-Smith
Affiliation:
University of the Witwatersrand, Johannesburg
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Summary

This chapter is concerned with numerical changes in tree and grass populations. Size structure distributions of savanna trees vary widely, suggesting episodic recruitment is widespread. Life-history transitions of savanna trees are erratic and contingent on prevailing conditions, especially fire return intervals. Savanna trees vary widely in potential longevity, from several decades to thousands of years. Tree populations may be expanding or contracting in response to climatic variation or contingent influences. Grasses increase numerically through proliferation of either tillers, tufts or runners. Grass populations may turn over between one year and the next following drought or heavy grazing. Refuge sites enable grass species to persist through prolonged droughts.

Type
Chapter
Information
Only in Africa
The Ecology of Human Evolution
, pp. 118 - 127
Publisher: Cambridge University Press
Print publication year: 2021

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References

Suggested Further Reading

O’Connor, TG; Everson, TM. (1998) Population dynamics of perennial grasses in African savanna and grassland. In Cheplick, P (ed.) Population Biology of Grasses. Cambridge University Press, Cambridge, pp. 333365.CrossRefGoogle Scholar
Staver, AC, et al. (2011) History matters: tree establishment variability and species turnover in an African savanna. Ecosphere 2(4):Art 49.Google Scholar

References

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